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Home My WebLink AboutAPA1124BRADLEY LAKE ~ HYDROELECTRIC POWER PROJECT FEASIBILITY STUDY VOLUME 1 REPORT OCTOBER 1983 A Stone & Webster Engineering Corporation ~-ALASKA POWER AUTHORITY_ ..... CONTRACT No. CC-08·3132 14500.14-H-(D)-1 BRADLEY LAKE HYDROELECTRIC POWER PROJECT FEASIBILITY STUDY VOLUME 1 REPORT OCTOBER 1983 & Stone & Webster Engineering Corporation ...___ALASKA POWER AUTHORITY_ .... COPYRIGHT, 1983 ALASKA POWER AUTHORITY THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OF THE ALASKA POWER AUTHORITY AND IS TO BE RETURNED UPON REQUEST. ITS CONTENTS MAY NOT BE COPIED, DISCLOSED TO THIRD PARTIES, OR USED FOR OTHER THAN THE EXPRESS PURPOSE FOR WHICH IT HAS BEEN PROVIDED WITHOUT THE WRITTEN CONSENT OF ALASKA POWER AUTHORITY. CERTIFICATIONS BRADLEY LAKE HYDROELECTRIC POWER PROJECT FEASIBILITY STUDY The technical material and data contained in this report and its Appendices were prepared under the supervision of the following indi- viduals and organizations: Volume 1 -Report Appendix-C -Transmission Line Analysis Appendix A -Geotechnical Studies Appendix B -Phase I Feasibility Study, Final Report Appendix D -Transmission Line System Appendix E -Instream Flow Assessment ~~ Theodore Critikos Deputy Project Manager Stone & Webster Engineering Corp. --i?&D~ Rohn D. Abbott Partner Dryden & LaRue Consulting Engineers Mic ael R. Joyce Project Manager Woodward-Clyde Consultants This study supervision Principal-n-Charge Stone & Webster Engineering Corp. VOLUME 1 - VOLUME 2 - VOLUME 3 - BRADLEY LAKE HYDROELECTRIC POWER PROJECT FEASIBILITY STUDY REPORT APPENDICES APPENDIX A APPENDIX B APPENDIX C APPENDICES APPENDIX D APPENDIX E GEOTECHNICAL STUDIES FEASIBILITY STUDY -CONSTRUCTION FACILITIES TRANSMISSION LINE ANALYSIS FEASIBILITY STUDY OF TRANSMISSION LINE SYSTEM BRADLEY RIVER INSTREAM FLOW STUDIES TABLE OF CONTENTS VOLUME 1 -REPORT 1 . EXECUTIVE SUMMARY. 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 1.10 1.11 1.12 INTRODUCTION BRADLEY LAKE FEASIBILITY STUDY RECOMMENDED PLAN . PRINCIPAL FEATURES OF RECOMMENDED PLAN ALTERNATIVES . . . . . . TECHNICAL CONSIDERATIONS . ENGINEERING AND ECONOMIC EVALUATIONS ENVIRONMENTAL ANALYSES PROJECT SCHEDULE . . . . PROJECT COST ESTIMATES . . POWER STUDIED AND ECONOMIC EVALUATIONS FINDINGS AND RECOMMENDATIONS 2. INTRODUCTION . . . 2.1 PROJECT LOCATION AND SETTING. 2.2 BACKGROUND AND PAST STUDIES 2.3 THE BRADLEY LAKE FEASIBILITY STUDY. 2.4 STUDY METHODOLOGY AND APPROACH. 2.5 STUDY PARTICIPANTS. 2.6 REPORT ORGANIZATION 3 . RECOMMENDED PLAN 3 . 1 GENERAL . 3.2 PRINCIPAL FEATURES OF RECOMMENDED PLAN. 3.2.1 Access Facilities ... 3.2.2 Dam and Spillway. . . 3.2.3 Construction Diversion .. 3.2.4 Permanent Outlet Facilities 3.2.5 Intake Channel .. 3.2.6 Intake Structure. 3.2.7 Gate Shaft. 3.2.8 Power Conduit . 3.2.9 Powerhouse. 3.2.10 Substation and Transmission 3.2.11 Construction Camps. . . 3.2.12 Buildings Grounds and Utilities 3.2.13 Middle Fork Diversion 4. ALTERNATIVES INVESTIGATED. 4.1 GENERAL 4.2 DAMS. 1-1 1-1 1-2 1-3 1-3 1-6 1-8 1-9 1-10 1-11 1-12 1-12 1-17 2-1 2-1 2-2 2-4 2-5 2-7 2-8 3-1 3-1 3-1 3-1 3-2 3-4 3-4 3-5 3-5 3-5 3-6 3-6 3-7 3-7 3-8 3-8 4-1 4-1 4-1 TABLE OF CONTENTS (Cont'd) VOLUME 1 -REPORT 4.3 SPILLWAYS ...... . 4.4 CONSTRUCTION DIVERSIONS 4.5 INTAKES .... . 4.6 GATE STRUCTURES ... . 4.7 POWER CONDUIT AND SURGE SHAFT 4.8 POWERHOUSE AND TAILRACE 4.9 TRANSMISSION FACILITIES 4.10 CONSTRUCTION CAMPS .. 4.11 MIDDLE FORK DIVERSION 5. TECHNICAL CONSIDERATIONS 5.1 5.2 5.3 5.4 GENERAL .... PROJECT GEOLOGY 5.2.1 Scope of Investigations. 5.2.2 Geologic Conditions .. 5.2.3 Seismotectonic Setting . 5.2.4 Seismic Design ..... HYDROMETEOROLOGY . . . . . . . . . . . . . . . . . . . . . . 5.3.1 General ..... . 5.3.2 Basin Description. 5.3.3 Climatology. 5.3.4 Hydrology .. SURVEY CONTROL. . . 6. ENGINEERING AND ECONOMIC EVALUATIONS 6.1 GENERAL CONSIDERATIONS ..... 6.2 ASSESSMENT OF PRINCIPAL FEATURES. 6.2.1 Power Tunnel Development .. 6.2.2 Economic Power Tunnel Diameters. 6.2.3 Middle Fork Diversion. 6.2.4 Dam Type ........ . 6.2.5 Turbine Types ...... . 6.2.6 Plant Capacity and Project Economics 6.2.7 Reservoir Operating Levels 6.3 PROJECT OPERATION ... 7. DETAILED PROJECT DESCRIPTION 7.1 ACCESS FACILITIES .. . 7.1.1 General .... . 7.1.2 Barge Basin and Dock 7.1.3 Access Roads .. 7.1.4 Airstrip .... 7.1.5 Emergency Access . 4-1 4-2 4-3 4-3 4-3 4-3 4-4 4-4 4-4 5-1 5-1 5-1 5-1 5-3 5-8 5-9 5-13 5-13 5-13 5-14 5-16 5-21 6-1 6-1 6-4 6-4 6-6 6-7 6-8 6-9 6-13 6-13 6-15 7-1 7-1 7-1 7-1 7-5 7-10 7-10 TABLE OF CONTENTS (Cont'd) VOLUME 1 -REPORT 7.1.6 Permanent Maintenance. · 7.1.7 Alternatives 7.1.8 General Geology. 7.2 DAM AND SPILLWAY. . 7.2.1 General .. 7.2.2 Dam and Spillway 7.2.3 Hydraulics . 7.2.4 Selection of Dam Height. 7.2.5 Geology and Foundation 7.2.6 Access . . 7.2.7 Alternatives 7.3 CONSTRUCTION DIVERSION. 7.3.1 General. . . 7.3.2 Diversion Tunnel 7.3.3 Permanent Outlet Facilities. 7. 3. 4 Hydraulics . . . . 7 'l c:: ~.~~,~-~ I • ...J • -1 0\::.V.l.VQ:f • • • • • • 7.3.6 Structures and Appurtenances 7.3.7 Access 7.3.8 Alternatives . 7.4 POWER CONDUIT SYSTEM. 7.4.1 General .. 7.4.2 Power Conduit. 7.4.3 Hydraulics . 7.4.4 Transient Analysis 7.4.5 Geology. . 7.4.6 Access . . 7.4.7 Alternatives 7.5 POWER PLANT . 7.5.1 General. . 7.5.2 Basic Data . 7.5.3 Tidal Considerations 7.5.4 Turbines and Generators. 7.5.5 Powerhouse Arrangement 7.5.6 Electrical Equipment 7.5.7 Mechanical Equipment 7.5. 8 Geology. . ... 7.5.9 Access . . . . 7.5.10 Powerhouse Alternatives. 7.6 SUBSTATION AND TRANSMISSION . 7.6.1 General. . .. 7.6.2 Transmission Line Analysis 7.6.3 Powerhouse Substation ... 7.6.4 Transmission Lines • 7.6.5 Kenai Peninsula-Anchorage Transmission Line. 7.6.6 Alternatives . 7-10 7-11 7-11 7-14 7-14 7-14 7-17 7-18 7-19 7-22 7-22 7-25 7-25 7-25 7-26 7-27 7=29 7-29 7-30 7-30 7-32 7-32 7-32 7-39 7-40 7-42 7-51 7-51 7-52 7-52 7-53 7-53 7-54 7-55 7-58 7-62 7-64 7-64 7-65 7-66 7-66 7-66 7-68 7-69 7-72 7-72 TABLE OF CONTENTS (Cont'd) VOLUME 1 -REPORT 7.7 7.8 7.9 CONSTRUCTION FACILITIES 7.7.1 General .... 7.7.2 Staging Areas. 7.7.3 Camp Areas . 7.7.4 Borrow and Waste Area Access 7.7.5 Construction at Dam Site 7.7.6 Construction at Powerhouse 7. 7. 7 Water Supply . . 7.7.8 Sewage Disposal. 7.7.9 Electric Power . 7.7.10 Other Facilities BUILDING GROUNDS AND UTILITIES. 7. 8. 1 General. . . . . 7 .8.2 Staffing . . . . . . 7.8.3 Maintenance Facilities 7.8.4 Operations Equipment . 7.8.5 Residential and Office Facilities. 7 .8.6 Water. . . . . .. 7.8.7 Wastewater Treatment and Disposal. 7.8.8 Fire Protection. . . . 7.8.9 Project Physical Security. 7.8.10 Solid Waste Facilities 7.8.11 Other Facilities MIDDLE FORK DIVERSION 7. 9.1 General. . .. 7.9.2 Recommended Plan 7. 9. 3 Geology. . . . . 7.9.4 Technical Details. 7.9.5 Dam, Gates and Conduit 7.9.6 Access ... 7. 9. 7 Alternatives 8. ENVIRONMENTAL ANALYSIS 9. 8.1 GENERAL . . . 8.2 MITIGATIVE STUDIES AND EVALUATIONS. 8.2.1 Instream Flow Studies. 8.2.2 Access to Project Site 8.2.3 Martin River Borrow Site 8.2.4 Waterfowl Nesting. 8.2.5 Moose Migration. . 8.3 IMPACT ADJUSTMENTS. . . . 8.3.1 Elimination of Alternative Structures. 8.3.2 Additional Project Features. LAND AND LAND RIGHTS . 7-74 7-74 7-74 7-75 7-77 7-77 7-78 7-78 7-79 7-80 7-'80 7-81 7-81 7-81 7-81 7-82 7-82 7-83 7-83 7-84 7-84 7-84 7-84 7-85 7-85 7-85 7-86 7-86 7-88 7-88 7-89 8-1 8-1 8-2 8-2 8-4 8-4 8-6 8-7 8-7 8-7 8-8 9-1 • TABLE OF CONTENTS (Cont'd) VOLUME 1 -REPORT 10. PROJECT SCHEDULE AND CONSTRUCTION CONTRACTS. 10.1 10.2 10.3 10.4 10.5 GENERAL. . . . ENGINEERING AND DESIGN CONSTRUCTION SCHEDULE. CONTRACTS. . . 10 .4 .. 1 General Civil Contract 10.4.2 Powerhouse Contract .. 10.4.3 Transmission Line Contract SUPPLY ORDERS .. 11. PROJECT COST ESTIMATES 11. 1 PROJECT COST ESTIMATE SUMMARY. 11.2 COST ESTIMATES FOR ECONOMIC ANALYSIS 12. POWER S~UiliES AN~ ECONOMIC EVALUATION. 12.1 12.2 12.3 12.4 INTRODUCTION . . . . . METHODOLOGY. . . . . 12.2.1 Electrical Generation Expansion Analysis System. 12.2.2 Life Cycle Cost. . . 12.2.3 Generation Expansion Optimization with EGEAS 12.2.4 Bradley Lake and Susitna Energy Dispatch ECONOMIC PARAMETERS AND DATA . . . 12.3.1 Reference Case Railbelt Load Projection. 12.3.2 Reference Case Fuel Price Projections .. 12.3.3 Existing Railbelt Generation System .. 12.3.4 Future Railbelt Electric Generation Alternatives 12.3.5 Sensitivity Studies. RESULTS. . ..... . 12.4.1 Reference Case . 12.4.2 Sensitivity Studies. 12.4.3 Evaluation of Selected 90 MW Bradley Lake Project 13. FINDINGS AND RECOMMENDATIONS 13.1 13.2 FINDINGS . . . . 13.1.1 Introduction 13.1.2 Technical Findings 13.1.3 Costs and Economics . . . RECOMMENDATIONS. . . . . . . . 14. BIBLIOGRAPHY 10-1 10-1 10-1 10-2 10-3 10-3 10-4 10-4 10-4 11-1 11-1 11-1 12-1 12-1 12-2 12-3 12-5 12-7 12-9 12-10 12-11 12-13 12-14 12-15 12-16 12-17 12-18 12-20 12-22 13-1 13-1 13-1 13-1 13-3 13-4 VOLill1E 1 -REPORT Table No. 1.3-1 5.3-1 5.3-2 5.3-3 5.3-4 5.3-5 6.2-1 6.2-2 6.2-3 6.2-4 7.1-1 7.1-2 7.4-1 7.4-2 7.4-3 7.4-4 7.4-5 LIST OF TABLES TITLE Technical Data Project Bradley Lake Hydroelectric Bradley River Flows at Lake Outlet Adjusted for Nuka Glacier Switch Middle Fork Flows at Diversion Dam Estimated Average Monthly Flows -Lower Bradley River Bradley River Flows at Lake Outlet Adjusted for Nuka Switch and Glacier Balance Change Bradley River Flows at Lake Outlet Adjusted for Nuka Switch and for Trend of Glacier Wasting. Manufacturer's Turbine Data (3 sheets) Manufacturer's Generator Data (6 sheets) ~ Preliminary Annual Energy -GWH Reservoir Elevations Sensitivity Analyses -90 MW Pelton -Two 45 MW Units Design Windspeeds (mph) At Sheep Point, Kachemak Bay, Alaska Design Wave Characteristics Chugachik Island Sheep Point and Hydraulic Transient Analyses -Francis Type Turbines Hydraulic Transient Analyses -Pelton Type Turbines Rock Core Properties Greywackes, Graywacke/ Argillite (Cataclastic), and Tuff Rock Core Properties -Massive Argillite Rock Core Properties -Foliated Argillite VOLUME 1 -REPORT Table No. 7.4-6 7.4-7 7.4-8 7.4-9 8.2-1 11.1-1 ii .2-i 11.2-2 11.2-3 11.2-4 11.2-5 12.3-1 12.3-2 12.3-3 12.3-4 12.3-5 12.3-6 LIST OF TABLES (Cont'd) TITLE Rock Gore Properties -Chert Rock Core Properties -Fresh & Altered Quartz Diorite -Terror Lake Tunnel Tunneling Conditions Portal .List of Thin Sections Fault & Fracture Zones, Proposed Habitat Maintenance Flows for Project Planning Purposes Feasibility Study Cost Estimate -90MW Preferred Plan (Summary sheet plus eleven back-up sheets) Cost Estimates of Study Alternatives Hydroelectric Plant O&M Costs Transmission Line O&M Costs Bradley Lake Powerhouse to Proposed Homer Electric Line 230kV Anchorage/Soldotna Transmission Line Cost Transmission Line O&M Costs -Anchorage/Soldotna 230kV Transmission Line Economic Evaluation Parameters Sherman H. Clark NSD Case Forecast -S'ummary of Input and Output Data Projected Peak and Energy Demand (NET) -Sherman H. Clark NSD Case Railbelt Peak Demand and Energy Projection (NET) -Sherman H. Clark NSD Case Historical Anchorage and Cook Inlet Peak Demand Historical Anchorage and Cook Inlet Energy Requirements VOLUME 1 -REPORT Table No. 12.3-7 12.3-8 12.3-9 12.3-10 12.3-11 12.3-12 12.3-13 12.3-14 12.3-15 12.3-16 12.3-17 12.4-1 12.4-2 12.4-3 12.4-4 12.4-5 LIST OF TABLES (Cont'd) TITLE Load Projection (Net) Sherman H. Clark NSD Case - Separation of Anchorage -Cook Inlet Load Into Anchorage and Kenai Peninsula Fuel Price Projections Scenario (2 sheets) Sherman H. Clark NSD Total Generating Capacity within the Railbelt System -1982 Existing Generating Plants in the Railbelt (5 sheets) Thermal Generation Plant Parameters, 1983 Dollars New Hydroelectric Generation Alternatives -Plant Parameters Bradley Lake Hydroelectric Project Plant Costs Susitna Hydroelectric Project Plant Costs Railbelt Peak Demand and Energy Projection (NET) -DOR 50% Scenario (July 1983) Fuel Price Projections -DOR 50% Scenario (July . 1983) Levelized Fuel Costs (1988-2037) Alternatives to Bradley Lake -Present Worth Cost of Optimum Expansion Plans Bradley Lake without Susitna Present Costs and Savings for Different Bradley Capacities -Total Railbelt Expansion Plans Bradley Lake without Susitna Present Costs and Savings for Different Bradley Capacities -Kenai Peninsula Expansion Plans Worth Lake Worth Lake New Generation Capacity Added Base Case (Thermal Plants Only) -Sherman H. Clark NSD Case New Generation Capacity Added -60MW Bradley Lake Project -Sherman H. Clark NSD Case VOLUME 1 -REPORT Table No. 12.4-6 12.4-7 12.4-8 12.4-9 12.4-10 12.4-11 12.4-12 12.4-13 12.4-14 12.4-15 12.4-16 12.4-17 12.4-18 12.4-19 LIST OF TABLES (Cont'd) TITLE New Generation Capacity Added -90MW Bradley Lake Project -Sherman H. Clark NSD Case New Generation Capacity Added 135MW Bradley Lake Project -Sherman H. Clark NSD Case Generation by Fuel Class -Base Case (New Thermal Plants Only) -Sherman H. Clark NSD Case Generation by Fuel Class 90MW Bradley Lake Project -Sherman H. Clark NSD Case Expansion Plan Summary Base Case (Thermal Plants) -Reference Case Load Expansion Plan Summary 90MW Bradley Lake Project -Reference Case Load Bradley Lake with Susitna -Present Worth Costs and Savings for Different Bradley Lake Capacities -Total Railbelt Expansion Plans Bradley Lake with Susitna -Present Worth Costs and Savings for Different Bradley Lake Capacities -Kenai Peninsula Expansion Plans Expansion Plan Summary 90MW Bradley Lake Project with Susitna -Reference Case Load Railbelt Generation Expansion Plans -Sensitivity Analysis to Railbelt -No-Growth Case New Generation (Thermal Plants Sensitivity Case Capacity Only) Added 0% Base Case Load Growth New Generation Capacity Added -90MW Bradley Lake Project -0% Load Growth Sensitivity Case Generation by Fuel Class -Base Case (New Thermal Plants Only) -0% Load Growth Sensitivity Case Generation by Fuel Class -90 MW Bradley Lake Project -0% Load Growth Sensitivity Case VOLUME 1 -REPORT Table No. 12.4-19 12.4-20 12.4-21 12.4-22 12.4-23 12.4-24 12.4-25 12.4-26 12.4-27 12.4-28 12.4-29 12.4-30 LIST OF TABLES (Cont'd) TITLE Generation by Fuel Class -90 MW Bradley Lake Project -0% Load Growth Sensitivity Case Expansion Plan Summary Plants) -No growth Case Expansion Plan Summary Project -No Growth Case Base Case (Thernal 90 MW Bradley Lake New Generation Capacity Added Base Case (Thermal Plants Only) -DOR SO% Case (July 1983) New Generation Capa~ity -Added 90MW Bradley Lake Project -DOR 50% Case (July 1983) Generation by Fuel Class -Base Case (New Thermal Plants Only) -DOR SO% Case (July 1983) Generation by Fuel Class 90MW Bradley Lake Project -DOR 50% Case (July 1983) Expansion Plan Summary -Base Case (Thermal Plants) -DOR 50% Case Expansion Plan Summary -90MW Bradley Lake Project -DOR 50% Case Capital Costs and Average Annual Energy -90MW Bradley Lake Project Feasibility Stage and Selected Values Selected 90MW Bradley Lake Project without Susitna -Present Worth Costs and Savings Expansion Plan Summary -Selected 90MW Bradley Lake Project -Reference Case Load VOLUME 1 -REPORT Figure 5.3-1 5.3-2 5.3-3 5.3-4 5.3-5 6.1-1 6.1-2 6.2-1 6.2-2 6.2-3 6.2-4 6.2-5 6.2-6 6.3-1 6.3-2 7.3-1 7.3-2 7.4-1 LIST OF FIGURES TITLE Annual Flow Duration Bradley Lake Outlet - Adjusted for Nuka Glacier Switch Only Annual Flow Duration -Middle Fork Annual Flow Duration -Lower Bradley River Annual Flow Duration Bradley River -with Glacier Mass Balance Adjustments Annual Flow Duration Bradley River -with Glacier Wasting Trend Removed Assessment of Principal Features -Bradley Lake Project Preliminary lnstream Flows Economic Diameter Analysis -Power Conduit -90MW Plant Alternative Concrete Gravity Dam Concept Energy Evaluations -Francis and Pelton Turbines Comparative Evaluations -Francis and Pelton Turbines Alternative -90MW Francis Unit Powerhouse (Sheet 1) Alternative -90ffi{ Francis Unit Powerhouse (Sheet 2) Streamflows -Bradley River at Bradley Lake Recommended Instream Flows 1979 Inflow -Outflow Hydrographs Diversion Tunnel Flood Routing Hydraulic Transients -Francis Units VOLUME 1 -REPORT Figure 7.4-2 7.4-3 7.4-4 7.4-5 7.4-6 7.4-7 7.4-8 7.4-9 7.6-1 7.9-1 12.2-1 12.2-2 12.2-3 12.4-1 12.4-2 12.4-3 LIST OF FIGURES (Cont'd) TITLE Hydraulic Transients -Pelton Units Thin Section Petrographic Examination -Graywacke Thin Section Petrographic Examination -Massive Argillite Thin Section Petrographic Examination -Foliated Argillite Thin Section Petrographic Examination -Cherty, Foliated Argillite Thin Section Petrographic Examination -Tuff Thin Section Petrographic Examination -Quartz Diorite Thin Section Petrographic Examination -Quartz Diorite Alternative SF6 Substation Hydraulic Rating Curves -Middle Fork Diversion Typical Bus Bar Cost Stages in EGEAS GeneTation Expansion Analysis Bradley Lake Dispatch By EGEAS Sherman Clark NSD Case DOR 50% Case (July 1983) Sherman Clark NSD Case -Selected 90MW Plant VOLUME 1 -REPORT Plate No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 LIST OF PLATES TITLE Location Map Overall Project Features General Plan Access Facilities Access Channel and Barge Basin Dock Structure Details General Arrangement Structures Dam, Spillway and Flow Concrete Faced Rockfill Dam -Sections and Details Spillway -Elevation and Sections Construction Diversion -Sections and Details Intake Channel and Gate Shaft Details Power Conduit -Profile and Details Sections and 90MW Pelton Powerhouse -Plans and Sections Sheet 1 90 MW Pelton Powerhouse -Plans and Sections - Sheet 2 Powerhouse Substation and Bradley Junction Middle Fork Diversion -Plan and Profile Middle Fork Diversion -Elevations and Details Project Design Floods and Reservoir Area Capacity Curves Reservoir Regulation Diversion Discharge 90MW Plant with Fish VOLUME 1 -REPORT Plate No. 20 21 22 23 LIST OF PLATES (Cont'd) TITLE Reservoir Regulation -90MW Plant without Fish Diversion Discharge Rating Curves Main One Line Diagram Project Schedule 1 EXECUTIVE SUMMARY 1. EXECUTIVE SUMMARY 1. 1 INTRODUCTION The role that Bradley Lake Hydroelectric Project will play in meeting the electrical needs of the State of Alaska has been under study for some time. Study of the Bradley Lake Project was initially authorized by the Federal Government in 1962 and since then, many studies and evaluations have been performed by the U.S. Army Corps of Engineers (COE) to determine the technical and economic feasibility of developing the power potential of Bradley Lake. The State of Alaska became directly involved in 1981 when the Alaska Legislature appropriated funds to initiate construction of the project. In 1982 the Legislature authorized the Alaska Power Authority to assume the development of the project, and in October 1982, the Power Authority's Board of Directors authorized pursuing design and construction of the project by the Power Authority. Shortly after assuming the responsibility for the Bradley Lake Project, the Power Authority issued a Request for Proposal in November 1982, soliciting professional services for the engineering and design work of the Bradley Lake Hydroelectric Project. Stone & Webster Engineering Corporation (SWEC) was selected as the Architect/Engineer and this selection was approved by the Board of Directors on March 14, 1983. The Powe-r Authority contract with SWEC, dated April 20, 1983 required that, prior to the initiation of engineering and design, a feasibility study be performed to re-evaluate the technical and economic feasibility of the project. These efforts were designated as Phase I -Feasibility Study, and had the following objectives: o Ascertain the technical feasibility of the project in sufficient detail to eliminate all major uncertainties. o Select the most attractive size plant and scheme of development for the Bradley Lake Hydroelectric Project. 1-1 o Determine the role that a Bradley Lake Hydroelectric Project will have as a power development in the overall energy plans for the State of Alaska and evaluate the economic merits of the project as compared to alternative generation in the State. 1. 2 BRADLEY LAKE PROJECT FEASIBILITY STUDY Beginning in April 1983 SWEC organized the scope of work of the Feasibility Study under· the following work tasks: o Data Collection o Review of Data o Technical Review Board o Conceptual Design of Common Items o Conceptual Design of 60 MW, 90 MW and 135 MW Plants o Evaluation of Construction Facilities o Quantity Development and Construction Cost o Power Study and Economic Analysis Approach o Geotechnical Investigations o Instream Flow Studies o Transmission Lines o Selection of Preferred Plan o Feasibility Report All of the above work tasks collection and review process were pursued resulted in a to completion. The data thorough understanding of previous work ana identified areas requiring further investigation. Previously identified areas of concern were evaluated and feasible solutions pursued. Conceptual engineering and design efforts permitted the assessment of previous concepts and the implementation of new innovative ideas. Geotechnical work resolved foundation uncertainties and hydrologic and instream flow studies substantiated the energy capabilities of the development. Cost and economic evaluations confirmed the economic merits of the Bradley Lake Hydroelectric Project. 1-2 1 . 3 RECOMMENDED PLAN The recommended plan developed for the Bradley Lake Project would use water stored at the lake and the effective pressure head between the lake and Kachemak Bay to generate electricity. A dam, at the outlet of the lake, will impound water and raise the lake. level thereby increasing the effective generating head. Additional water is provided with the diversion of natural flows from the Middle Fork drainage basin to Bradley Lake. Stored water is conveyed to the generating facilities through a concrete lined tunnel and a buried penstock power conduit. The power generating facilities are housed within an above ground enclosed powerhouse located at the eastern shoreline of Kachemak Bay. Two separate and parallel transmission lines, each about 20 miles long, connect the project to a transmission line to be constructed by others. Table 1.3-1 gives a summary of the salient Technical Data for the project development. 1. 4 PRINCIPAL FEATURES OF RECOMMENDED PLAN Access Facilities The prime access to the site during construction of the project and later during project operation will be by water using an access channel and barge basin. Additional acces.s is provided by an airstrip located in the vicinity of the powerhouse. Helicopter pads are also located at key areas within the Project boundaries. Access roads are provided to serve the project during construction and permanent operation. Three road networks have been established: one network serves the airstrip, powerhouse, dock, staging area and lower camp; a second network will connect the lower camp to the upper camp and continue to the dam area; and a third network will allow access to a construction borrow area. Dam and Spillway A concrete faced rockfill dam with an ungated concrete gravity spillway is to be constructed at the outlet of Bradley Lake. These structures will impound the natural inflows and allow raising the present lake level by 1-3 about 100 feet to elevation 1,180. The dam crest is set at elevation 1,190 and the total top length is about 605 feet. The maximum dam height above its foundation is about 125 feet. Upstream and downstream cofferdams are provided for construction of the main dam. The reservoir impounded by the dam will contain an active storage of about 284,000 acre-feet at normal operating pool elevation 1, 180 with a surface area of about 3,820 acres. An ungated concrete gravity overflow spillway is located over the bedrock saddle formation at the right abutment area of the lake outlet. The spillway has an ogee set at elevation 1, 180 with a crest length of 165 feet. The length of the spillway including abutments is approximately 230 feet. The spillway is designed to pass the Standard Project Flood, as well as the Probable Maximum Flood. Construction Diversion Diversion of the natural outflow from Bradley Lake during construction of the main dam and other structures at the lake outlet will be accomplished by a horseshoe shaped tunnel excavated through the right rock abutment, approximately 100 feet east of the lake outlet. The 470 foot long tunnel will discharge into the large natural pool downstream of the main dam. A concrete intake portal will be constructed with provisions for steel bulkhead gates. Permanent Outlet Facilities Permanent outlet facilities will be incorporated into the construction diversion tunnel. The outlet facilities will serve as low level outlets providing for emergency drawdown of the reservoir and diversion of flows to the Bradley River for fish habitat. Flows will be controlled by hydraulically operated slide gates. 1-4 Intake Channel Stored water is conveyed to the power tunnel intake structure through a 50 foot wide by 360 foot long intake channel. The channel is located at the left bank area and allows the reservoir to be drawn to elevation 1060. Power Gondui t The power conduit includes all water passage structures that are used to bring water from Bradley Lake to the Kachemak Bay Powerhouse. From an intake structure provided at Bradley Lake, a 18,820 feet long, 11 foot diameter underground power tunnel connects Bradley Lake to the powerhouse. Located about 800 feet downstream of the intake structure is a circular shaped gate shaft which contains two hydraulically operated gates for emergency closure of the power conduit. The concrete and steel lined tunnel connects to a buried steel penstock at the tunnel portal near the powerhouse. The steel penstock then bifurcates into 8 feet diameter steel br~ches leading to the hydraulic turbine generating units. Each branch is equipped with a spherical valve located immediately upstream of the units. Powerhouse and Tailrace The powerhouse is located near sea level on the eastern shore of Kachemak Bay. The powerhouse will contain two Pelton hydraulic turbine generating units having a combined rating of 107 MW. Each unit is capable of generating 45 MW at minimum head with a nominal operating speed of 300 rpm. The powerhouse substructure is constructed of reinforced concrete which is enclosed with an insulated steel superstructure. The tailrace is an excavated trapezoidal unlined channel approximately 100 feet long extending from the powerhouse into the tidal flats. Substation and Transmission The substation is located adjacent to the northeastern end of the powerhouse and is rated 115,000 volts, 3-phase, 60 Hz. It contains the main power transformers, circuit breakers, disconnecting switches, and line takeoff towers. 1-5 Power from the Bradley Lake substation is carried via two parallel 115 kV transmission lines.-These lines are constructed using wood pole, H-frame structures and aluminum conductors, steel reinforced. Each line is designed to transmit the full output of the plant, in the event one line is lost. The Bradley Lake lines are connected to another 115 kV transmission line which transmits power between Soldotna and Fritz Creek. The connection to this line, at a location called Bradley Junction, is about 20 miles from the power plant. Middle Fork Diversion The Middle Fork Diversion is located approximately one mile northeast of Bradley Lake in an adjacent basin, and provides seasonal diversion of water into Bradley Lake. The diversion scheme consists of a 20 feet high embankment dam and 1,900 feet of 6 feet diameter steel conduit. Other features include a spillway and bypass conduit which will be used initially for construction diversion and later to divert the natural winter flows downstream into the Middle Forko 1. 5 ALTERNATIVES In arriving at the selection of the Recommended Plan of development, it was necessary to review the previous studies and to appraise various design alternatives in order to develop the most economical and sound plan of development. The major alternatives considered in the study are as follows: Dam and Spillway The following dam and spillway configurations were reviewed and considered: o Concrete gravity dam incorporating a concrete spillway section o Concrete gravity dam with a separate ungated spillway dam o Rockfill dam with a side channel spillway o Rockfill dam with a separate ungated spillway dam o Double curvature arch dam o Roller compacted concrete gravity dam o Concrete faced rockfill dam with a separate spillway 1-6 The recommended plan includes the concrete faced rockfill dam with a separate ungated spillway dam. Construction Diversion Various diversion schemes were analyzed. These included tunnel arra~gements through the right and left abutments at the lake outlet and also buried conduit through the main river channel. A tunnel alignment through the right abutment with diversion flow discharging into a natural stilling pool was judged the best and included in the Recommended Plan. Power Conduit The previous COE concept of the intake located at the right bank of Bradley Lake was reviewed for applicability. As an alternative, intake located on the left bank was analyzed and found feasible. From this location three alternative power tunnel alignments to the powerhouse were investigated. All three alignments utilized deep settings with concrete lined tunnels and buried steel penstocks. The COE concept had included a higher set tunnel with an exposed surface penstock along the hillside above the powerhouse. The lower setting for the tunnel and buried penstock was determined to be the most desirable alternative. Powerhouse The COE had previously investigated above and underground powerhouses and concluded that the above ground arrangement would be the most economical. SWEC concurred and investigated the above ground powerhouse only. The COE powerhouse arrangement included three generating units whereas SWEC adopted the more conventional and economical two unit arrangement as an alternative. Middle Fork Diversion The COE had previously investigated a steel bin wall dam, concrete gravity dam, and a timber buttress dam for diverting the Middle Fork flows. To maximize use of natural materials in the area, SWEC analyzed two variations 1-7 of rockfill dams: a concrete faced rockfill and a steel sheet pile cut-of£ rockfill. The latter was judged the most attractive scheme and was included in the Recommended Plan. 1. 6 TECHNICAL CONSIDERATIONS The project's regional geologic setting and the hydrologic influences of its environment largely dominated the spectrum of technical considerations addressed in the study. These two areas substantially controlled the engineering and economic feasibility of the more salient features of the project. Geology The Bradley Lake Project is located in an area of the Kenai Mountains which is composed primarily of mildly metamorphosed argillite and graywacke rock. These rocks have been uplifted and deformed from past seismotectonic activity and shaped by continuous erosional processes. The two major geologic features within the project site are informally known as the Bradley River and Bull Moose Faults. Although no direct evidence of recent activity along these or regional faults is known, all are considered capable of independent earthquake generation. Statistical analysis of the magnitude of historical ground motion from earthquakes indicates that earthquake accelerations ranging from 0. 3g to 0. 75g should be used in the final design of the major surface structures. Evidence gathered to date has not revealed any geologic features with potential for ground displacement at the main dam or powerhouse. Although the potential for ground shifting associated with large earthquakes exists along the power tunnel alignment at the two major faults, it would be possible to repair any resulting damage. Hydrology The intensity and seasonal distribution of storms producing precipitation within the Bradley Lake drainage basin reflect the maritime climate of the 1-8 region. The runoff response from rainfall precipitation, which is influenced largely by the geologic conditions, exhibits a rapid rise in s_treamflow, with little flow going into groundwater storage. Recorded streamflow data at the Bradley Lake outlet consequently reflects the maritime influences and geologic conditions of the basin. Analysis of these data indicate that highest streamflows occur during May through October. Snow and glacial melt water contribute a substantial portion during the spring and summer months and rainfall contributes to streamflow during the fall months. Flood peaks during this period have exceeded 5,000 cfs, however, streamflows during the drier winter period, seldom exceed 75 cfs. To account for possible future changes in streamflows and its effect on power production of the project, the historical streamflow record required several adjustments for glacial influences. Initial adjustments were made to the first half of the records to reflect Nuka Glacier runoff being ·;._\,; redirected into the Bradley Lake drainage basin. Other adjustments were then made to the entire record to reflect both historical and potentia 1 climatic effects of the glaciers on streamflow. Although these adjustments resulted in noticeable yearly fluctuations in streamflow in comparison with the initial adjustments, the overall effect of the more conservative glacial adjustment on annual energy production was found to be a reduction in generated energy of less t~an 2 percent. The Probable Maximum and Standard Project Floods as developed by the COE were used in this study without modifications. inflows of 31,300 cfs and 14,400 cfs, respectively. 1. 7 ENGINEERING AND ECONOMIC EVALUATIONS The floods have peak Various engineering studies and economic analyses were conducted in selecting the most attractive scheme of project development. In pursuing this goal, previous work and findings were reviewed and new ideas and concepts developed in the preliminary stages of the feasibility study. A screening process was established which identified the more promising alternatives and project features for further evaluation. These 1-9 evaluations included engineering and operating considerations as well as cost comparisons and economic appraisals. A list of alternatives and project features used in comparative evaluations together with the sequence in which they were studied follows. o Use of Tunnel Boring Machine for power tunnel excavation o Economical power tunnel diameter o Francis or Pelton turbine/generator equipment o Middle Fork Diversion facilities o Rockfill vs: concrete gravity main dam o Plant capacity o Bradley Lake reservoir operating levels These features as well as the alternatives, which affect the economic benefits of the project, were matrix developed of energy evaluated using computer simulations and a potential versus alternatives. Economic benefits were then computed and compared with estimated costs together with engineering and environmental considerations to arrive at the preferred plan for development of the project. 1 . 8 ENVIRONMENTAL ANALYSES The Bradley Lake Hydroelectric Project is in an area of high peaks, glacier, wildlife and sub-alpine terrain. The area is inhabited by a diversity of wildlife species. Although the site itself is free of human habitation, the project can be constructed with minimal impact and will provide benefits serving the population of the Kenai Peninsula and the developing area of south central Alaska. The Corps of Engineers' (COE) environmental studies identified the effects of developing the Bradley Lake Project on biological and sociojcultural resources, and addressed these in its Final Environmental Impact Statement (FEIS) issued in August 1982. Areas of environmental concern, identified in the FEIS, are slow releases for downstream fish habitat; resolution of access to the project; rehabilitation of the Martin River borrow area; ...... ....;_ ..... _. plans for developing waterfowl nesting; and assessment of moose mig~ations. 1-10 Since the SWEC Recommended Plan is essentially similar to the COE's preferred plan for Bradley Lake, there should not be other unresolved issues or impacts. In fact, the SWEC Plan reduces the environmental impacts with the following elimination.s: o The 2800 foot long above ground penstock extending from the powerhouse to the tunnel portal. o The two mile access road from the powerhouse to the tunnel portal. o Surge shaft and associated access road. o Exposed steel penstock and bridge as required for the power tunnel crossing over the Bradley River. Further, and as part of this feasibility study, instream flow studies have been conducted to assess downstream fish habitat; means of access to the project were re-assessed; pla~s are being considered for developing waterfowl nesting and for the rehabilitation of the Martin River b2Frow area; and a program for studying moose migrations is being planned, ~or early implementation. Data from the instream flow studies show that fish habitat at the lower Bradley River can be maintained by regulating river flows or even improved. The re-assessment of providing project access, by means other than the preferred plan, showed that alternatives would either present greater environmental impacts, cost more, or both. Mitigation of waterfowl nesting and for the Martin River borrow will be developed as part of the license application effort to the Federal Energy Regulatory Commission (FERC). The assessment of moose migratory habits has been authorized and will be implemented as part of other project development efforts. Some further assessment and environmental evaluation work may be required in relation to the proposed transmission line and upper camp area. 1 . 9 PROJECT SHCEDULE The Project Schedule extends over a five year period with the initial construction activities dependent on the award of a FERC License. Receipt of the FERC License is anticipated in May 1985, with commercial operation 1-11 of the units scheduled for October 1988 and completion of the project by the end of 1988. Should award of the FERC License be delayed, seasonal scheduling problems will ensue, and the project schedule including the commercial operation dates, will be delayed. The engineering and design is scheduled to commence in February 1984, coincidental with the submittal of the FERC License Application to the Regulatory Commission. The construction schedule for the Bradley Lake project is predicated on three major construction contracts (1) General Civil Contract; (2) Powerhouse Contract and (3) Transmission Line Contract. Several major equipment supply contracts such as hydraulic turbines, generators, governors, powerhouse crane, gates, valves, pumps and electrical accessory equipment will be awarded separately to support engineering-design needs and delivery dates to meet the required construction erection schedule. 1. 10 PROJECT COST ESTIMATES The Overnight Cost Estimate for the preferred 90 MW plan is $283,019,000. This cost includes: direct material, labor, and construction equipment; engineering and design cost; cost for the management of construction; Owner's cost including previous expenditures realized for project studies and development; land and land rights cost; all risk insurance; and a contingency of 25 percent. The Overnight Cost Estimate refelcts cost as of July 1983. 1.11 POWER STUDIES AND ECONOMIC EVALUATION The objectives of the power study and economic evaluation of the Bradley Lake Project were to identify the economic advantages or disadvan:tages of the Project for the Railbelt and to select the preferred plant capacity. Several variations in Railbelt generation expansion plans were evaluated. Separate analyses were performed for generation expansion plans using thermal power plants (gas-fired combined cycle, gas-fired combustion turbine, and coal-fired steam turbine), the Susitna Hydroelectric Project combined with thermal plants, and the Bradley Lake Project (with and 1-12 without Susitna) for the three proposed project capacities of 60MW, 90MW, and 135MW. Also, sensitivity studies were performed to determine the effect of variations in the Railbelt load growth rate on the economic performance of the Bradley Lake Project. The primary tool used in this evaluation was a computer program developed for the Electric Power Research Institute. This program, Electric Generation Expansion automatically develop Analysis System, electric generation provided expansion the capability plans based on to the characteristics and costs of alternative generation sources, existing unit characteristics and retirement dates, and electric load data. The total present worth cost for each generation expansion plan was determined, with the lowest cost plan being the optimum. This computer program was also used to perform a two-area analysis where reserve sharing and economy interchange were modeled between the Kenai Peninsula and the remainder of the Railbelt. This analysis was used to apportion costs between the two regions and to evaluate the effect of transmission limitations between Anchorage and the Kenai Peninsula on the present worth costs of the generation expansion plans. An assessment of the differences in transmission costs associated with generation expansion plans including and not including the Bradley Lake Project was essential to the power study. The primary data source for the study was the Harza-Ebasco Susitna FERC application of July 1983. Information derived from this document included items such as fuel prices and escalation rates, new generation alternatives, Susitna characteristics, and existing generation units in the Railbelt. The Reference Case Railbelt electric load forecast used in the Bradley Lake study was also derived from this source. The Reference Case forecast, titled "Sherman H. Clark Associates NSD Case," has an average annual compound load growth rate of about 2. 8 percent for the period 1983 through 2007. The power study and plant capacity selection were based on Bradley Lake capital costs and average anual energy values developed during the 1-13 feasibility stage evaluations. following: These plant parameters included the Bradley Lake Capacity, MW * Includes IDC. 60 90 135 Capital Cost,* Millions 1983$ 275.70 287.95 303.50 Average Annual Energy, GWH 330.5 345.4 356.6 The power study evaluations indicate that the Bradley Lake Project is economically beneficial for the Railbelt at any of the three proposed plant capacities, both with and without the presence of Susitna. The optimum capacity for Bradley Lake is dependent on and sensitive to the projected load growth rate for the Railbelt. The differences in present worth cost between the three proposed capacities for alternative load growth projections are relatively small. For the Reference Case load projection, the 90MW Bradley Lake Project shows the largest net benefit for the Railbelt without the presence of Susitna, while the 60MW and 90MW Bradley Lake Projects exhibit approximately equal benefits when Susitna is present. The Reference Case present worth costs for the cases without Susitna are as follows: Present Worth, Millons 1983~ Total Railbelt Kenai Peninsula Bradley Lake Savings Due to Savings Due to Capacity, MW Total Cost Bradley Lake Total Cost Bradley Lake 0 (Base Case)* 5,832 904 60 5,517 315 605 299 90 5,464 368 599 305 135 * 5,535 297 695 209 *Includes 230 kV Anchorage/Soldotna transmission line. 1-14 For the total Railbelt, the Bradley Lake savings range from 5.1 to 6. 3 percent of the base case present worth cost. The savings for the Kenai Peninsula alone (taking into account reserve sharing and economy interchange with the rest of the Railbelt) varied tram 23.1 to 33.7 percent of the base case. The Reference Case present worth.costs for the cases including Susitna are as follows: Present Worth, Millons 1983~ Total Rail belt Kenai Peninsula Bradley Lake Savings Due to Savings Due to Capacity, MW Total Cost Bradley Lake Total Cost Bradley Lake 0 (Base Case)* 5,724 674 60 5,548 176 531 143 90 5,549 175 523 151 135 * 5,658 66 624 50 *Includes 230 kV Anchorage/Soldotna transmission line. With Susitna, the Bradley Lake savings range from 1. 2 to 3. 1 percent for the total Railbelt and from 7.4 to 22.4 percent for the Kenai Peninsula alone. Two sensitivity cases were evaluated to determine the economic impact on Bradley Lake if the Railbelt electric load growth is less than the Reference Case. The two cases included an assumed load growth of zero percent per year (with the Reference Case fossil fuel price projections) and a load growth and fossil fuel price projection titled "DOR 50% Case." For the no-growth sensitivity study, the 1983 Railbelt electric load was assumed to remain constant for the study period. The present worth costs, for the total Railbelt without Susitna, are as follows: 1-15 Present Worth~ Millions 1983~ Bradley Lake Savings Due to Capacity, MW Total Cost Bradley Lake 0 (Base Case) 3,194 60 2,966 228 90 * 2,990 204 135 * 3,010 184 *Includes 230 kV Anchorage/Soldotna transmission line. The 60MW Bradley Lake Project is the preferred capacity under a no-growth scenario. The second sensitivity study using the July 1983 "DOR 50% Case" was performed for only two generation expansion plans. These plans without Susitna included a base case (new thermal plants) and a case with the 90MW Bradley Lake Project plus thermal plants. The results are as follows: Case Base* 90MW Bradley Lake Present Worth Cost Millions 1983$ 3,461 3,305 * Includes 230kV Anchorage/Soldotna transmission line. Under the "DOR 50% Case," the installation of the 90MW Bradley Lake Project results in a present worth savings of about $156 million for the total Railbelt. Last~y, an evaluation was performed for the selected 90 MW Bradley Lake Project to determine the economic effect of changes in the feasibility stage values for plant capital cost and average annual energy. After selection of the 90 MW plant as the preferred capacity, detailed reviews of the plant capital cost and average annual energy were performed by SWEC. As a result 1-16 of these reviews, the 90 MW plant capital cost was increased from $287.95 million to $300 million (1983 dollars including IDC), and the average annual energy was increased from 345.4 GWH to 369.2 GWH. The 90 MW Bradley Lake Project was reevaluated with these revised parameters under the Reference Case load and fossil fuel price projections. The resulting present worth costs (without Susitna) are as follows: Present Worth, Millions 1983$ Savings Due to Total Cost Bradley Lake Base Case 90 MW Bradley Lake Project 5,832 5,455 377 As before, significant life-cycle savings result by using the selected 90 MW Project in place of thermal generation alternatives for the Railbelt. The selected 90 MW Project present worth cost is slightly lower than the;: value associated with the feasibility stage plant, indicating that the increase in capital cost is more than offset by benefits from the additional average annual energy generated. 1. 12 FINDINGS AND RECOMMENDATIONS Findings The major aspects of developing the Bradley Lake site have been reviewed and analyzed during this Feasibility Study. Conceptual design drawings have been developed, alternative designs evaluated, construction costs estimated, and the cost benefits of the three sizes of plants measured against alternative types of generation. The results are reflected in the Recommended Plan. The main findings are: o The 60 MW, 90 MW, and 135 MW Pelton plants produce about the same average annual energy, however, based on given load growth criteria, the 90 MW plant is the most economical choice for developing the project. 1-:17 o The level Bradley Lake should be ·raised some 100 feet for added benefits. Of the three maximum operating levels of the lake studied, elevation 1170, 1180 and 1190, elevation 1180 was judged as the most attractive. o The most economical method to raise the level of Bradley Lake, is to construct a concrete faced rockfill dam at the mouth of the lake and a separate concrete ogee spillway at the right abutment. o The power tunnel between Bradley Lake and the powerhouse can be bored with a tunnel boring machine and/or conventional techniques which are both technically feasible. o Geotechnical considerations and findings show that acceptable foundation and rock conditions exist at the locations of proposed project structures. o The Pelton type turbine is preferred, mainly because of lower project costs and the ability to follow greater fluctuations of peak power loadings. o An above ground powerhouse containing two generating units is preferred. o The Middle Fork Diversion, used to divert seasonal flows into Bradley Lake, is economically viable. o Diversion for construction is technically feasible by a tunnel through the right·abutment. Also, this tunnel can be converted into a permanent outlet facility for downstream releases after construction. o Land and land rights should pose no problems for construction of the Bradley Lake Hydroelectric Project, as the majority of the project lands were withdrawn in 1966 by Public Land order 3953 for the purposes of development of the project. The withdrawal included about 40,000 acres of Federal lands, whereas the project reservoir and structures require approximately 4,500 acres with the remaining used for protection of the watershed. 1-18 o The power plant output should be transmitted over a two circuit 115 kV transmission line system with each line capable of handling the full plant load. The selected 90 MW plant will not require another transmission line between Soldotna and Anchorage as the existing 115 kV line is capable of providing reserve sharing and economy interchange between Anchorage and the Kenai Peninsula. o The project can be developed in a manner that is responsive to environment and impacts and known environmental concerns can be resolved o The project cost estimates and the economic evaluation shows that: o The Recommended Plan of the 90 MW can be developed at an estimated overnight cost of $283,019,000, July 1983 price base. o Economic evaluations of th~ 90 MW installation shows that the Bradley Lake is economically beneficial for the Railbelt, both with and without the presence of the proposed Susitna Hydroelectric Project. Recommendations Based on the above findings it is recommended that: o The project be developed using two Pelton hydraulic turbines to generate a minimum of 90 MW, a concrete faced rockfill dam, a machine bored concrete lined tunnel, the Middle Fork diversion and a two circuit parallel transmission line. o To avoid lengthly delays and subsequent potential cost increases, the Power Authority should proceed with the Bradley Lake Project by initiating the preparation of a FERG License Application. o Unresolved environmental concerns and issues should be addressed during the early stages of FERG License Application preparation. 1-19 TECHNICAL DATA BRADLEY LAKE HYDROELECTRIC PROJECT (Based on Recommended Plan of Development) PROJECT FEATURES: Reservoir Elevation of existing lake surface, feet Elevation of normal full pool water surface, feet Elevation at minimum operating pool, feet Elevation at emergency drawdown, feet Elevation at Spillway Design Flood, feet Area of reservoir at full pool, acres Area of reservoir at minimum pool, acres Initial active storage capacity, acre-feet . M<iitional storge tor emergency generation, acre-feet Bradley Lake Dam Sheet 1 of 3 1,080 1,180 1,080 1,060 1,190.6 3,820 1,568 284,150 31,200 Type Length, feet Height of maximum section, feet Top of dam elevation, feet Concrete Faced Rock Fill 605 125 1,190 Bradley Lake Spillway Spillway type Spillway crest elevation, feet Gross spillway length, feet Spillway crest length, feet Power Tunnel Length, (concrete & steel lined), feet Nominal Diameter (lined) , feet Intake invert elevation, feet Unga ted Ogee 1,180 230 165 TABLE 18,820 11 1,030 1.3-1 Liner TECHNICAL DATA BRADLEY LAKE HYDROELECTRIC PROJECT (Based on Recommended Plan of Development) Steel liner & Penstock Type Outside Diameter, feet Length, feet Material Min. Yield Strength, psi Penstock Length, feet Outside diameter at portal feet Material Min. Yield Strength, psi Diameter of Bifurcation, feet Powerhouse Plant, KVA (Nameplate rating) Number of Units Type of Turbine Turbine Rating at 1130 feet rated net head, Hp Rating of Generating Unit, KVA (nameplate) Maximum Operating Pool Elevation, feet Minimum Operating Pool Elevation, feet Maximum Tailwater Elevation, feet Minimum Tailwater Elevation, feet Centerline Turbine Runner Elevation, feet Bottom of Turbine Chamber, feet Unit Spacing, feet Project Generation Sheet 2 of 3 Embedded 11 2,400 AS'IM A710. 85,000 135 11 AS'IM A7l0 85,000 8.0 112, 6Q_O 2 Pelton 73,900 56,300 1,180 1,080 11.4 -6.0 15.0 -6.0 43.0 Flow regime is Bradley River, Middle Fork diversion, and releases for fish habitat. Yearly firm energy Average annual energy TABLE 334.1 GWH 369.2 GWH 1.3-1 Sheet 3 of 3 TECHNICAL DATA BRADLEY LAKE HYDROELECTRIC PROJECT (Based on Recommended Plan of Development) Switchyard and Transformers Type Generator Bus Type Rating Enclosure In powerhouse Outside powerhouse Main transformers Number Rating Circuit Breaker Number Type Rating Line number Type Voltage, kilovolts Transmission Line Conductor size, KCM, ACSR; "Dove" Overall length overhead section, miles Conventional Copper conductor Non-segregated Phase 15000 volts; 3000 amps Continuous; 80,000 amps Momentary Ventilated Enclosed; weatherproof 2 33~ 8/4-5/56. 3 MVA Three phase, 60 Hz 3 Oil 1200 amps 2 parallel H-Frame Wood Pole 115 556.5 20 Tailwater Data For Powerhouse BEAR COVE BEAR COVE BRADLEY MLLW MSL PROJECT TIDES DATUM DATUM DATUM -- HT 25.00 15.39 11.37 MHHW 18.17 8.56 4.78 MHW 17.60 7-99 + 3.87 MSL 9.61 o.oo 4.02 MLW 1.61 -8.00 -12.02 MLLW o.oo -9.61 -13.63 LT -6.00 -15.61 -19.63 Unless otherwise noted, all elevations given are based on project datum. "----------TABLE 1.3-1 2 INTRODUCTION 2. INTRODUCTION 2. 1 PROJECT LOCATION AND SETTING The proposed Bradley Lake Hydroelectric Power Project would be located on the Kenai Peninsula, about 105 miles south of Anchorage, Alaska. Bradley Lake, with a natural elevation of about 1080 feet, is located in the Kenai Mountain range. Geographically, Bradley Lake is about 27 miles northeast of Homer, Alaska. Access to the project site is limited at present to boat at high tide, or helicopter. The Kenai Hountains, above an elevation of 3, 000 feet, have been eroded by glaciers and form rather rough terrain characterized by cirques, horns, and deep U-shaped valleys. Above this elevation, the mountains are covered principally by glaciers, except for scattered peaks which protrude above the ice. Valley glaciers are present in the upper reaches of most valleys and in some ~ases are a major source of water for rivers,. lakes and streams on the lower Kenai Mountain slopes . The Bradley Lake area, with steep sloped reliefs reaching 4,300 feet, is dominated by the lake and gorge of the Bradley River. The lake is about 3 miles long and varies from 0. 2 mile to about 1. 2 miles in width. The maximum depth of the lake is about 268 feet. Except for the southeast portion of the lake, where Kachemak Creek and the Nuka Glacier flow into the lake, the land rises abruptly from the lake shore, with some portions nearly vertical. Bradley Lake inflow is derived principally from rainfall and snow melt with some contribution from glacier melt of the Kachemak and Nuka glaciers. Outflow from the lake flows northwestward into the Bradley River. The river flows in a gorge which is between 725 feet and 1,200 feet deep and up to 750 feet wide. The river channel passes through several very narrow reaches, which include rapids and waterfalls, before reaching the floodplain and tidal flats of Kachemak Bay. 2-1 The project site area is considered to be located in a major earthquake region, with recorded earthquake magnitudes of 6. 0 -6. 9 on the Richter Scale. Several historical earthquakes have occurred within a radius of 500 miles of Bradley Lake. The area of the Kenai Peninsula is strongly influenced by the maritime climate that prevails along coastal regions adjacent to the Gulf of Alaska. Cool summers and moderate winter temperatures prevail, with occasional winter intrusions of cold Arctic air masses. Fog, rain, and clouds occur frequently in the area and gusty, turbulent winds are common in the upper basin and near Kachemak Bay. Precipitation is light during late winter and early spring, and increases to maximum amounts from August through December, varying with geographic location and elevation. Precipitation in the lower elevations is predominately rain with upper elevations receiving snow. The project area is moderately forested with white spruce, birch, aspen, and willow along the areas adjacent to Kachemak Bay. Areas above an elevation of about 1,000 feet have very _little growth and are essentially barren. The entire Kenai Peninsula area has been classified as being generally free from permafrost. The waters of Kachemak Bay are subject to tidal fluctuations of up to about 23 feet. Although some ice forms, the bay is essentially open. Bradley Lake surface waters begin to freeze by early winter and ice cover stays on the lake till late April or early May. Ice thickness varies as a mixture of slush and solid ice, with an estimated solid ice thickness of about 28 inches. The Bradley Lake area encompasses several fish and wildlife habitat areas. The area has a high diversity of species and the Fox River Flats, comprising the estuarine areas of the Fox, Sheep, and Bradley Rivers, at the head of Kachemak Bay, has been designated as "critical habitat area". 2. 2 BACKGROUND AND PAST STUDIES Many studies and evaluations have been performed over the years to determine the technical and economic feasibility of developing the Bradley Lake drainage sy_stem into a hydroelectric power project. Most of this work 2-2 was conducted by the Corps of Engineers (COE) and various architect/engineering firms subcontracting to the COE. The bibliography contained in this report provides a listing of the studies previously performed on the Bradley Lake development. Study of the Bradley Lake Project was initially authorized by the Federal Government in 1962. Engineering, design, economic and other studies were undertaken by the COE. The results of the COE findings and recommendations are presented in a series of Design Memoranda, culminating with the issuance of the General Design Memorandum No. 2 in February, 1982. This later memorandum was issued in two volumes, Volume 1, "Main Report" and Volume 2, "Appendices". The COE studies and findings concluded that the Bradley Lake Project is technically feasible, and economically attractive. The COE recommended the development of a project with 135 MW of capacity, utilizing three Francis type hydraulic turbine units to generate up :to an average annual energy of about 356 GWH. This installation was pref~,rred over two other alternatives studied, namely a 60 t·fW and a 90 t·fW plant. Substantial work was accomplished by the COE and its subcontracting firms in collecting base line data relating to both environmental and technical aspects of the recommended project. The environmental efforts resulted in the preparation and issuance of a Final Environmental Impact Statement, dated August, 1982. The COE had reached the milestone for initiating definitive engineering-design; however, due to lack of funding, work on the project could not continue to completion. The involvement of the State of Alaska with the project commenced in 1981 at which time the Alaska legislature appropriated funds to initiate construction of the project. Later, in 1982, the state legislature appropriated additional funds, and authorized the Alaska Power Authority to assume the development of the project. The Power Authority's Board of Directors, in October 1982, authorized the design and construction of the project by the Power Authority. Federal legislation deauthorizing the project was passed in December, 1982. Additional studies were performed by the Power Authority on costs, project economic and other factors to further assess project feasibility. Key 2.-3 studies included cost estimates by the firm of Ebasco Services, Inc., and project-economic assessments by the firm of R.W. Beck and Associates, Inc .. 2. 3 THE BRADLEY LAKE FEASIBILITY STUDY Shortly after assuming the responsibility for the Bradley Lake Project, the Power Authority issued a Request for Proposal (RFP) -APA-83-R-027, on November, 1982, soliciting professional services for the engineering and design work of the Bradley Lake development essentially as recommended by the COE. Stone & Webster Engineering Corporation (SWEC) was selected and this selection was approved by the Power Authority Board of Directors in March 1983. The SWEC contract with the Power Authority required that, prior to the initiation of definitive engineering-design work, preliminary conceptual engineering-design studies be performed to re-evaluate the technical and economic feasibility of the project. These efforts were designated as Phase I -Feasibility Study and had the following objectives: o As~ertain the technical feasibility of the project in sufficient detail to eliminate major uncertainties. o Re-evaluate the previously studied installations with respect to capacity, energy and costs, and select the most attractive plant and scheme of development. o Determine the role that a Bradley Lake power development will have in the overall energy plans of the Power Authority and evaluate its economic merits in comparison to alternative generation mixes. The study was to consider the impact of the project on: (1) the entire Railbelt electrification plan, (2) its affect on the Anchorage-Kenai Peninsula area, and (3) its implication on the Kenai Peninsula alone. The study was to consider "with or without Susitna" project scenario and various mixes of fossil fueled generating plants and transmission line arrangements. The scope of services of the study included resource assessment, field surveys, and hydrologic, glacier trending, geotechnical, environmental, 2-4 engineering-design, cost, and economic evaluation studies necessary to assess project feasibility. A specific objective of the study is to select a preferred installation that best responds to the energy needs of the area or areas to be served. This report documents and summarizes the Phase I Feasibility Study efforts. 2. 4 STUDY METHODOLOGY AND APPROACH The Bradley Lake Feasibility Study included the following Scope of Work: o Data Collection Compiled data developed by others which are applicable to the study and distribute these data. o Review of Data -Reviewed the information compiled, noted applicable areas and communicated and exchanged this information with pr9ject pers<?nnel. o Technical Review Board -The project Technical Review Board contributed to conceptual development and assessed applicability of project concepts. o Conceptual Design of Common Items -Conceptualized engineering of items that are common to the 60, 90 and 135 MW installations, including preparation of preliminary drawings. o Conceptual design of 60, 90 and 135 MW Plants -Engineering-design efforts for the conceptual development of powerplants using two turbine-generator units for each size of plant. Each installation were developed for Francis type turbine units and Pelton type turbine units and conceptual arrangement drawings were prepared for costing efforts. o Evaluation of Construction Facilities -Performed technical evaluations and determined costs of key facilities required to support construction activities as well as those facilities needed for permanent plant operation of the project. 2-5 0 Quantity Development and Construction Cost Performed take-off of the various installations and alternatives. cost estimates for comparative assessments and for use in evaluation studies. quantity Developed economic o Power Study and Economic Analysis Approach -Considered modelling of base and alternative generation-transmission line power development scenarios to explore the role and economic feasibility of Bradley Lake on the Railbelt area, the Anchorage-Kenai Peninsula and on the Kenai Peninsula alone. o Geotechnical Investigations -Collected geotechnical data and performed field explorations to support project evaluation. 0 Instream Flow Studies Collected technical . and scientific data relating to affected fish habitat areas of the Bradley River. o Transmission Lines -Developed conceptual engineering/design and cost estimates for transmission line systems associated with project development. o Selection of Preferred Plan -Evaluation of data and study results to select a recommended installation. 0 Feasibility Report Prepared this report to present findings, conclusions, and recommendations. All of the above activities were pursued to completion. The data collection and review process resulted in a thorough understanding of previous work. The review process identified areas requiring further investigation. Previously identified areas of concern were evaluated and feasible solutions pursued. Conceptual engineering and design efforts permitted the assessment of previous concepts and the implementation of new innovative ideas for project development. Geotechnical work resolved areas of major uncertainties; specifically in the development of the power tunnel and dam. Hydrologic and instream flow studies substantiated the energy 2-6 capabilities of the development. Cost and economic evaluations confirmed the feasibility of the Bradley Lake Hydroelectric project. The goal of the above described feasibility study was to arrive at a selection of the most attractive plant size and scheme of development. This was achieved, and Stone and Webster recommended a 90 MW plant, with two Pel ton type hydraulic turbines, be the selected scheme of development for the Bradley Lake Hydroelectric Project. The Overnight estimated cost ·of this selected scheme is $283,019,000. The scheme of development includes a concrete faced rockfill dam, a machine bored tunnel, the Middle Fork diversion and a scheme for augmenting flows for aquatic habitat. The recommended scheme does not require a Soldotna/Anchorage transmission line as the existing 115 kV line is capable of providing reserve sharing and economy interchange between Anchorage and the Kenai Peninsula for the 90 ~M Bradley Lake installation. 2.5 STT-~Y PARTICIPANTS Assisting SWEC in studying the feasibility of the Bradley Lake Project were the following Alaskan firms who contributed to the study work in the areas indicated: o Woodward-Clyde Consultants -Performance of instream flow studies and evaluation of aquatic habitat flow requirements. o Shannon & Wilson, Inc. -Geotechnical data collection and analyses. o R&M Consultants, Inc. -Performance of engineering-design studies and cost development relating to the various construction and civil facilities of the project. o Dryden & LaRue Consulting Engineers -Engineering and design studies and cost development of electrical transmission lines. 2-7 2.6 REPORT ORGANIZATION This report is arranged under the following main headings: 1. Executive Summary 2. Introduction 3. Recommended Plan 4. Alternatives Investigated 5. Technical Considerations 6. Engineering and Economic Evaluations 7. Detailed Project Description 8. Environmental Analysis 9 . · Land and Land Rights 10. Design and Construction Schedule 11. Cost Estimates 12. Power Studies and Economic Evaluation 13. Findings and Conclusions 14. Bibliography In Section 1, the Executive Summary provides a synopsis of the engineering and economic evaluation studies that led to the selection of the optimum scheme of developing hydroelectric power at Bradley lake. Section 2 describes the background, location, setting, previous studies and the Stone & Webster Feasibility Study Program on the Bradley Lake Hydroelectric Project. Section 3 details the Recommended Plan and Sections 4 through 12 describe the technical, environmental and economic findings as well as the cost estimates and proposed construction schedule for building the project. Section 13 presents the conclusions and recommendations. Reports prepared by SWEC and its subcontractors are included in the appendices. Pertinent data collected for the feasibility study are listed in the bibliography, Section 14, at the end of the main report. 2-8 3 . · RECOMMENDED PLAN 3.1 GENERAL The recommended plan for development of the Bradley Lake Project uses water stored at the lake and the effective pressure head between the lake and Kachemak Bay to generate electric energy. A concrete faced rockfill dam is proposed at the outlet of the lake to impound water and increase the available generating head. Additional water is provided with the diversion of natural flows from the Middle Fork drainage bas in to Bradley Lake. Stored water is conveyed to the generating facilities through a concrete and steel lined tunnel and a buried penstock power conduit. The power generating facilities are housed within an above ground enclosed powerhouse located at the eastern shoreline of Kachemak Bay. Two separate and parallel transmission lines, each about 20 miles long, connect the project to the transmission line to be constructed by Homer Electric Association. Plates 1, 2 and 3 show the location, overall features, and general plan of ~he project, respectively. 3. 2 PRINCIPAL FEATURES OF RECOMMENDED PLAN 3. 2.1 Access Facilities The prime access to the site during construction of the project and later during project operation will be by water using an access channel and barge basin located northwest of Sheep Point. Additional access will be provided by an airstrip north of the powerhouse and helicopter pads located at key areas within the Project as shown on Plate 4. The access channel and barge basin areas, shown on Plate 5, are formed by dredging to a bottom elevation -14. The access channel, basin and dock is capable of accommodating seCj.-going barges and tugs. Barge movements based upon a 10 feet draft could be accomplished on 99 percent of all high tides, or on 49 percent of all hourly tidal stages. The barge basin will allow the barges to rest on the bottom during the low tide cycle. The dock 200 feet 3-1 by 50 feet. A reciprocating off -loading ramp is provided for roll-on-roll-off unloading operations. A small section of the basin will allow sheltered anchorage for a limited number of small boats. Access roads are provided to serve the project during construction and permanent operation. Three road networks, as shown on Plate 4, have been established. One network consists of a 2.5 mile, 28 feet wide, two lane road and serves the airport, powerhouse, dock, staging area and lower camp. The second network consists of a 5.7 mile, 28 feet wide, two lane road that will connect the lower camp to the upper camp and continue on to serve the dam area. The third network is a 1.4 mile long construction type temporary access road that will allow access to the Martin River delta borrow area. Fill-borrow sections of this temporary access are 18 feet wide, one lane travelway while graded portions have a 28 foot wide, two lane, travelway. A contemplated one lane road to the surge shaft area will not be required under the recommended plan. ln general the roads are cut and fill. Surfacing gravel material will come from the Martin River borrow area. Culverts and bridges are provided as required. A portion of the road between Sheep Point and the Powerhouse is located in the tidal mud flats and will be used as a retention dike for the disposal of dredged material from the access channel and barge basin. Special rip-rap armor is provided along this section of access road for wave protection and slope stability. 3.2.2 Dam and Spillway A concrete faced rockfill dam with an ungated concrete gravity agee shaped spillway is to be constructed at the outlet of Bradley Lake. These structures will impound the natural inflows and allow raising the present lake level by about 100 feet to elevation 1,180. The rockfill dam structure occupies the main river channel near the lake and has a crest set at elevation 1, 190 and a total top length of about 605 feet. The maximum dam height above its foundation is about 125 feet. A plan and details of the proposed dam are shown on Plates 7 and 8, respectively. 3-2 The rockfill material needed to construct the dam are quarried from a rock knoll that is located near the left abutment, upstream of the proposed dam. This excavation also facilitates the development of the intake channel. Material excavated for the preparation of dam foundations and for the spillway will be partially used in cofferdam development with the excess material placed in suitable areas along the left bank or in the main dam. An upstream cofferdam is being provided to block off lake flows during the construction of the main dam. The cofferdam is a rockfill embankment structure with filter and impervious material dumped at its upstream face to seal off water. The structure, which has a crest height at elevation 1,100 is located immediately at the iake outlet. Material for its construction will come from the quarry area and from material removed for the preparation of the main dam foundation area. A similar type cofferdam structure is provided downstream to block off water from entering the construction area during lake diversion. .This structure is designed to be incorporated into the embankment of the main dam. The reservoir created behind the dam will impound an active storage of about 284,150 acre-feet above a normal minimum operating pool at elevation 1,080. At the full normal operating pool of elevation 1,180, the reservoir has a surface area of about 3,820 acres. to elevation 1,060 for maintenance of The reservoir can be drawn down structures and for additional emergency generation. The additional active storage gained is about 31,200 acre-feet. Minimum and selective reservoir clearing is being considered, as necessary for operation of the plant. The ungated concrete gravity overflow spillway is located over the saddle formation at the right abutment area of the lake outlet, Plates 7 and 9. The spillway has an ogee set at elevation 1,180 with a crest length of 165 feet. The overall length of the spillway including its adjacent concrete 3-3 abutments is approximately 230 feet. The spillway is designed to pass the routed Probable Maximum Flood under a discharge head of about 10 feet and the routed standard Project Flood under a discharge head of about 5 feet. 3.2.3 Construction Diversion Diversion of the natural outflow from Bradley Lake during the construction of the main dam and other structures at the lake outlet will be accomplished by a horseshoe shaped tunnel excavated through the right rock abutment approximately 100 feet east of the lake outlet, Plate 7. The 22 foot diameter unlined tunnel will be 470 feet long and discharge into the large natural pool downstream of the main dam. The intake portal will be constructed of reinforced concrete with provisions for a steel bulkhead. The tunnel invert will slope downstream on a hydraulically steep slope from elevation 1, 078 at the inlet portal to elevation 1, 074 at the tunnel outlet, Plate 10. Construction of the tunnel will be by conventional drill and blast techniques, with the initial heading advancing from the downstream end. Steel sets installed at the portals will be embedded in concrete as protection against the relatively high flow velocity when discharging the design flood. After the main dam and power tunnel intake are completed the steel bulkhead gates will be installed in the intake portal and construction of the permanent outlet facilities within the tunnel will be completed including partial concrete lining of the downstream tunnel section. 3.2.4 Permanent Outlet Facilities Permanent outlet facilities will be incorporated into the construction diversion tunnel. The outlet facilities will serve as low level outlets, and provide for emergency drawdown of the reservoir and for diversion of fish habitat flows to the Bradley River. The facility will consist of a concrete plug, 30 feet long, constructed about 260 feet downstream of the portal, with two 3.5 feet high by 5.5 feet 3-4 wide conduits formed within the plug. Each conduit will be controlled by two hydraulically operated slide gates. The two downstream gates will control the outflow during normal operations and the two upstream gates will serve as guard gates during emergencies. A hydraulic power unit and suitable air-oil accumulator will be provided to operate the gates, Plate 10. 3. 2. 5 Intake Channel Stored water is conveyed to the power tunnel intake structure through an intake channel. The channel is about 50 feet wide and 360 feet long and is located at the ·left bank area. The channel is excavated down to elevation 1, 030 and allows the reservoir to be drawn down to elevation 1, 060 for maintenance of structures and for an additional 20 feet of active storage for emergency generation. Rock traps are being provided along the channel invert and in front of the intake structure to collect fallen and ice carried rocks, Plates 7 and 11. 3. 2. 6 Intake Structure An intake structure is located at the downstream end of the intake channel. The intake is excavated in rock as an extension of the upper end of the power tunnel. The excavation is suitably shaped and concrete lined for proper hydraulic performance. Removable steel trash racks installed at the inlet, preclude floating debris from entering the power conduit, Plate 12. 3.2. 7 Gate Shaft A vertical gate shaft is being furnished along the power tunnel alignment. The gate shaft is a concrete lined 22 feet circular shaft about 173 feet high, Plate 12. Two hydraulically operated slide gates are being provided to serve as emergency shut-off gates for flow shutdown and for unwatering the tunnel for maintenance. One gate is considered active during such an emergency while the second serves as a backup. The passive gate is used for servicing the active gate. The gate shaft will be dry and provisions 3-5 are -made within the structure for in-place maintenance of the gates. Access to the gate shaft is from the road serving the dam. 3 . 2 . 8 Power Conduit The concrete lined power tunnel conduit is approximately 18,860 feet long, and connects the intake structure to the turbine generating units. The nominal tunnel flow diameter is 11 feet. Starting from the intake, the power tunnel consists of a 950 feet long horizontal tunnel that connects to a 810 feet long shaft, inclined at 55° from the horizontal. A 38 feet long bend is provided at each end of the shaft. The power tunnel continues for about 14,450 feet to the beginning of a concrete and steel lined tunnel section that is about 2400 feet long and extends to the tunnel portal near the powerhouse. An exposed, girder reinforced, steel "roll-out" penstock section is provided near the portal. From this point on, the power conduit consists of a 135 feet long steel penstock section that bifurcates into two flow_ lines, one for each of the two turbine generating units. The penstock section is encased in concrete and buried below grade for most of its length. A surge shaft w·ill not be required for the power tunnel conduit. Material excavated from the tunnel will be used either for airfield fill or for upgrading access road surfaces. The arrangement of the power conduit is shown in Plate 12. 3.2.9 Powerhouse and Tailrace The powerhouse is located just above sea level on the northeast shore of Kachemak Bay. The powerhouse will contain two Pelton turbine generating units having a combined rating of 107 MW. Each unit is capable of generating 45 MW at minimum head with a nominal operating speed of 300 rpm. The powerhouse, penstock, bifurcation, and power tunnel portal are situated on an excavated rock bench at elevation 40. The powerhouse is constructed of reinforced concrete with an insulated steel superstructure. The tailrace is an excavated trapezoidal, unlined channel approximately 100 feet long extending from the powerhouse into the tidal flats. The discharge from the turbines will flow across the tidal flats to connect with Kachemak Bay. Excavated material will be used in the construction of a laydown area and a switchyard adjacent to the powerhouse excavation along 3-6 the shoreline of the tidal flats. Plates 13 and 14 show plans and details of the powerhouse arrangements. 3.2.10 Substation and Transmission The substation is located adjacent to the northeastern end of the powerhouse., It is rated 115,000 volts, 3-phase, 60 HZ, and contains the main power transformers, line and tie circuit breakers, disconnecting switches, coupling capacitor voltage transformers, and line take-off towers. Conventional, oil-filled, outdoor equipment is utilized for power circuit breakers, and power transformers. The disconnecting switches are manually-operated, vertical-break units. Each generator is connected to a three-phase power transformer, power circuit breaker and then to a 115 kV transmission line. Between the two outgoing lines there is a normally closed power circuit breaker. This allows power in the Soldotna-Fritz Creek transmission line to flow through the Bradley Lake substation. The -.1'Jt · substation is designed to transmit the full output ·of the Bradley -Lake .,.. Plant, during maintenance of or failure of one of the line breakers. Plate 15 shows the general plan of the substation. Transmission of the power from the Bradley Lake plant is via two, parallel 115 kV transmission lines. These lines are constructed utilizing wood pole, H-frame structures and aluminum conductors, steel reinforced (ASCR). Each line is designed to transmit the full output of the plant, in the event one line is lost. The Bradley Lake lines are connected to a 115 kV transmission line which transmits power between Soldotna and Fritz Creek. The connection to this line, at a location called Bradley Junction, is about 20 miles from the power plant. A typical wood pole transmission line structure and the Bradley Lake Junction arrangement are shown on Plate 15. 3. 2.11 Construction Camps Two construction camps are planned to accommodate personnel during project construction. The lower camp area is located on the right bank of Battle Creek, approximately one mile southeast of Sheep Point. The upper camp is located near the upper dam access road about one mile west of the Bradley Lake outlet. The area is designed to accommodate 240 beds and the upper 3-7 camp 210 beds. Each camp will have housing, dining, recreation, offices, utilities, sewer, and other support facilities. The lower camp area will also be used as the site for the permanent housing facilities to be constructed for the plant operation and maintenance personnel. The camps will be operated by the contractor during the project construction and will be sized to also provide facilities for visiting personnel, Authority's Construction Manager and Engineering support and the Power staff. The general location for these construction camps is shown on Plates 3 and 4. 3.2.12 Buildings, Grounds and Utilities Permanent buildings and grounds will be limited to those required to support operation and maintenance of the Project. These facilities are located at the lower construction camp site area and consist of four residences provided for supervisory and operations and maintenance personnel and their families. In addition, a bunkhouse will be provided for maintenance personnel in the event of major maintenance. The permanent facilities will be totally selfcontained with water and sewage facilities, electric service from the powerhouse station service system, and a standby electric generator. The permanent facilities will also include a warehouse, a fully equipped machine shop, and a storage yard each sized to support anticipated project material, spare part storage, and maintenance requirements. The powerhouse and powerhouse substation will also be self-contained with fire, water and sewage facilities, station service power service, a standby electric generator, and station batteries for emergency power to critical equipment and controls. Microwave and other means of communications will be provided from Homer to the powerhouse and other key project facilities. 3.2.13 Middle Fork Diversion The Middle Fork Diversion is located approximately one mile northeast of Bradley Lake in an adjacent basin, and diverts up to 450 cfs of water into Bradley Lake during May through October. The diversion consists of a small 3-8 rockfill embankment dam and 1, 900 feet of 6 feet diameter steel flow line. The rockfill darn is approximately 20 feet high and has a steel sheet pile central cut-off wall. The dam will be constructed of material excavated from the 30 feet wide, 12 feet deep, and 210 feet long chute spillway located in the right abutment. A 6 feet diameter steel pipe will be used initially for construction diversion and later as a low level outlet to pass the natural winter flows downstream into Middle Fork. An entrance sluice gate and manual operator is provided for closure of the low level outlet. Also, a 6 feet diameter, steel pipe is provided to serve as the main diversion conduit into Bradley Lake. A closure sluice gate and manual operator is located at the pipe entrance. The pipe is buried for its total length to allow animal passage over the pipe and to preclude damage from snow creep and avalanche. The entrance sluice gate· for the main diversion conduit will be fully opened during May through October and closed from November through April. The plan and profile of the Middle Fork diversion and details of the recommended rockfill dam structure and its appurtenances are show:p. on Plates 16 and 17~ respectively. 3-9 4 ALTERNATIVES INVESTIGATED 4. ALTERNATIVES INVESTIGATED 4.1 GENERAL A large number of alternatives were investigated during the study. In addition, reviews were made of concepts developed under studies by the COE and others. The alternatives studied in the selection of the preferred plan are briefly discussed in this section and in greater detail in the report section describing the specific features of the plan. 4.2 DAMS The following types of dams were considered: o Concrete gravity dam with a flip bucket spillway positioned at its central monolith section. o Concrete gravity dam with an ungated concrete gravity spillway in the right abutment saddle. o Concrete double curvature arch dam in the immediate vicinity of t!le lake outlet. o Roller compacted concrete gravity dam. o Concrete faced rockfill dam. Preliminary engineering evaluations and, when appropriate, engineering analyses were conducted on the above dam types· to select the best two alternatives for more in depth engineering and cost analyses. The two dam types considered in depth were the concrete gravity dam and the recommended concrete faced rockfill dam. 4. 3 SPILLWAYS Due to the topographical and geologic features at the site, the only practical locations for a spillway to handle the Design Floods would be 4-1 either the left or right abutments or a design incorporating the spillway into the main dam at the lake outlet. The dam type and location also affect the selection of the spillway location, type, and design details. Side channel spillways were extensively studied by the COE in conjunction with rockfill dams. The COE also investigated a spillway within the main central section of a concrete gravity dam. The present study investigated and recommends an ungated agee type spillway located in the right abutment saddle. Two types of spillways were investigated by the COE, an uncontrolled free discharge agee shaped crest and a gated spillway. The gated spillway was abandoned due to the higher capital and maintenance cost as well as operational constraints. SWEC agrees with this conclusion and only investigated the uncontrolled agee spillway. 4.4 CONSTRUCTION DIVERSIONS The diversion concepts reviewed in this study considered major engineering and cost factors affecting overall project development. These factors included the impacts of alignment. and arrangement on the power tunnel, intake structure, cofferdams, spillway, construction ease, and the accessibility during and after construction. In addition, hydrologic, hydraulic, and environmental factors were considered for the various schemes studied. Previous studies conducted by the COE and others were the basis for the initial review. Several other diversion schemes were analyzed and reviewed. These included tunnel arrangements through the right and left abutments at the lake outlet, and a buried conduit through the main river channel. Variations in each of these schemes were also reviewed. An alignment through the right abutment with the diversion flow discharging into the large stilling pool was judged the best in terms of the above considerations and is the recommended concept. 4-2 4.5 INTAKES Previously identified intake structures studied by the COE were reviewed and, in addition two new intakes were investigated. These were: o A bellmouth intake in combination with a channel excavated within the cofferdammed area. o A bellmouth intake in combination with a channel developed as part of the quarrying operations required for the rockfill dam. The latter of the two is the preferred concept. 4. 6 GATE STRUCTURES Gate structures considered by previous studies were reviewed. The preferred·gate structure, consisting of a concrete lined circular·shaft and housing two hydraulically operated slide gates also was studied. 4. 7 POWER CONDUIT AND SURGE SHAFT Three alternative power tunnel alignments, connecting the left bank of the river channel to the powerhouse were investigated. The three power tunnel alignments considered utilize a deeply set concrete lined tunnel and eliminate the exposed penstock. Because of topographic relief, the surge shaft location was fixed to that identified under previous studies. 4. 8 POWERHOUSE AND TAILRACE The COE had previously investigated both above and below ground powerhouses, and pressure and non-pressure tailraces for the below ground powerhouse and concluded that an above ground arrangement would be most economical. SWEC concurred with this COE finding and investigated only above ground powerhouse arrangements. Conceptual powerhouse arrangements were developed for Francis and Pelton types turbines for 60 MW, 90 MW, and 135 MW capacities. Two unit powerhouse arrangements were considered in the 4-3 powerhouse arrangements to take advantage of the resulting cost economy. In all cases the powerhouse was located so that the tailrace arrangements considered were founded on rock. Variations considered for the Francis powerhouse included machines with and without synchronous by-pass valves and a power tunnel with and without a surge shaft. 4. 9 TRANSMISSION FACILITIES A transmission line corridor other than that proposed by COE was studied and is the recommended corridor discussed within this report. In addition, two separate transmission lines that would connect the Kenai Peninsula to Anchorage were evaluated. 4.10 CONSTRUCTION CAMPS The COE had previously looked at several camp sizes with alternatives of road and wat~)r access from Homer and concluded that a construction camp alternative would be most economical. SWEC concurs and considered the use of a single camp to be located near the mouth of Battle Creek and a two camp scenario which has a lower camp near the mouth of Battle Creek and an upper camp on the plateau west of Bradley Lake. Each camp considered would provide services to support construction activities. Permanent project buildings were investigated only in the lower camp site area. 4. 11 MIDDLE FORK DIVERSION The COE had previously investigated a steel bin wall dam, concrete gravity dam, and a timber buttress dam with buried or above ground steel diversion pipes. SWEC concurs with the COE' s recommended buried steel d-iversion pipe. To make the maximum use of material natural to the diversion site, two additional dam types were considered: concrete faced rockfill dam and a rockfill dam .with a steel sheet pile cut-off. The concrete faced rockfill alternative was selected for development along with a spillway 4-4 excavated in right abutment. The steel sheet pile cut-off rockfill alternative was developed with a side channel spillway located in the right abutment. 4-5 5 TECHNICAL CONSIDERATIONS 5. TECHNICAL CONSIDERATIONS 5.1 GENERAL Two main areas of technical considerations are identified as having a major impact on project feasibility. These are project geology and hydrometeorology. The geologic conditions found at the project area substantially control the engineering and economic feasibility of structures such as the dam, tunnels and powerhouse. Hydrometeorologic conditions relate primarily to the energy producing capability of the project and also affect the engineering design and economics of the main project structures. A good understanding of conditions and limitations regarding these two technical aspects is important in the development of engineering concepts and project economic evaluations. A third but less critical technical consideration was identified during the course of the study. This consideration relates to the horizontal and vertical survey control which establish the physical interrelationships of the project structures. This consideration was found to have a minimal impact on project feasibility but it did point out the need for developing an accurate horizontal and vertical survey control network for the project. These technical considerations are discussed in greater detail below. 5 . 2 PROJECT GEOLOGY This section outlines the current scope of investigations, geologic conditions at the site, the seismotectonic setting of the site and seismic design guidelines. The major portion of work in defining geologic conditions was performed by Shannon & Wilson (S&W), Fairbanks, Alaska, subcontractors to SWEC. Details of site geologic conditions are included in their report, Appendix A of this report. 5. 2. 1 Scope of Investigations Previous investigations of the site subcontractors, and the U. S. Geological 5-1 by the COE, Survey (USGS) , their various acting at the request of the COE, were available for study and use in the current investigations. These previous studies were of sufficient detail to allow the current program to focus on specific areas rather than the site area as a whole. The scope of current investigations is as follows: o Review of existing data accumulated by the COE, their subcontractors, and the USGS. These reports are listed in the "Bibliography" section at the end of this section of this report. This work was performed jointly by SWEC and S&W personnel. o Reconnaissance geologic mapping, including aerial photograph interpretation, and field checks of previous work were conducted by S&W, assisted by SWEC personnel. Work was concentrated at the dam site, powerhouse site and, particularly, along the tunnel alignment. Where necessary for overall understanding of conditions in the area, selected off-site locations were visited. o Four borings and one test pit were made by S&W. Three borings recovered rock core; at the left abutment area of the dam and along the tunnel alignment at its projected intersection with the Bradley River and Bull Moose Faults. The fourth boring was made in soil in the general location of the barge basin; both disturbed and undisturbed samples were taken for laboratory testing. Results of these activities are outlined in following sections describing the geology of individual project facilities. o Laboratory tests of soil samples from the boring in the barge basin area were made by S&W and are outlined in Section 7.1.8. o Laboratory tests of selected portions of rock core were made under the direction of Dr. A. J. Hendron of the Technical Review Board, Atlas Copco Jarva, Inc. and The Robbins Company. The results are presented in tabular form in Section 7. 4. 5 . o Petrographic examination of selected portions of rock was done by SWEC. Results are included in Section 7.4.5.8. 5-2 o A final report, Bradley Lake Hydroelectric Power Project, Geotechnical Studies; August, 1983, was prepared by S&W and is included as Appendix A. o SWEC Geotechnical personnel provided input to the feasibility level design efforts detailed in this report. 5.2.2 Geologic Conditions This section is divided into a brief synopsis of the regional geologic setting and a more extensive outline of the general site geologic conditions. 5. 2. 2. 1 Regional Geologic Setting The portion of the Kenai Mountains in which the Bradley Lake Project -~rea -is located is composed of mildly metamorphosed rocks of upper Mesozoic Age, informally named the McHugh Complex. These rocks are thought to have been deposited in deep water on the continental margin. The rocks have been uplifted, deformed, and shaped by erosional processes. Accentuated by glacial and colluvial influences, the local topography is dominated by conspicuous lineaments that are surficial expressions of a complex network of faults or major joint sets that are the result of the activity of the seismic region in which the area lies. The Kachemak and Nuka Glaciers, along with several smaller alpine glaciers, feed meltwater into the Bradley-Lake drainage. The proposed reservoir will reach to within approximately 1. 5 miles of the Nuka Glacier and 2. 5 miles of the Kachemak Glacier. Although they do not have extensive rubble at their termini, their meltwaters contain a significant amount of glacial rock flour, which is responsible for the cloudy condition of the water in Bradley Lake. An expression of the primary tectonic influence on the project area is found in the Gulf of Alaska, where, about 185 miles southeast of Bradley Lake, the axis of the Aleutian Arch-Trench occurs sub-parallel to the 5-3 prevalent NE-SW strike of the prominent tectonic features found around Bradley Lake and the surrounding region. Immense compressional forces generated by the plate tectonics activity in the Kenai Region have resulted in deformation of the upper crust materials of the Kenai Peninsula in the form of folding, jointing and faulting. Of the several major regional fault systems that express this deformation, two faults are found in the vicinity of the Bradley Lake Hydroelectric Power Project. The Eagle River Fault crosses through the southeastern portion of Bradley Lake, and the Border Ranges Fault forms the northern front of the Kenai Mountains and flanks the northwest portion of the project area passing beneath the length of Kachemak Bay. Two other locally major faults cross the proposed tunnel alignment, the Bradley River Fault and the Bull Moose Fault. Like the Eagle River and Border Ranges Faults, the Bradley River and Bull Moose Faults strike in the general NE-SW direction that is characteristic of the regional tectonic grain, and they have been suggested to be extensions -of the--Bo-rder Ranges Fault. Togertliei -with. several -other randomly oriented faults, these lineaments create much of the topographic features found in the Bradley Lake project area. 5.2.2.2 Site Geologic Conditions -General The project area is underlain by weakly metamorphosed sedimentary strata of the McHugh Complex. This bedrock is locally mantled by unconsolidated glacial, alluvial, and colluvial deposits and, below tree line, is generally obscured by vegetation and soil cover. The McHugh Complex in the project area is comprised primarily of weakly metamorphosed graywacke, argillite, and cherty argillite. Locally these rocks are intruded by dacitic dikes. The graywacke, argillite, and cherty argillite of the McHugh Complex have a complex distribution as a result of their intense deformation and structural juxtaposition. Recognizable bedding planes and marker beds are generally absent or masked by tectonic foliation. Many contacts appear to be tectonic rather than depositional, and individual lithologic units commonly are discontinuous over short distances. Many of the thicker lithologic units either pinch out or are truncated within a few hundred 5-4 feet along their trend, whereas the thinner units often can be traced no more than a few feet to few tens of feet. Consequently, projection of lithologic units and rockmass characteristics from surface exposures laterally into areas where the rock is obscured and vertically into the subsurface is necessarily speculative. 5.2.2.3 Lithologic Units For the purpose of this evaluation, the bedrock has been subdivided into five lithologic units based on their distinctive rockmass properties. These units are graywacke, massive· argillite, foliated argillite, foliated cherty argillite, and dacite intrusives. The sedimentary classifications represent further subdivisions of the graywacke and argillite units utilized in earlier studies. The general characteristics of these bedrock units are discussed below. The gray-..;acke is highly indurated, dark gray to dark greenish gray,· yery fine to medium grained, weakly metamorphosed sandstone. Fine, irregular quartz and calcite veins are locally common in the graywacke. The unit is massive with little or no evidence of bedding except for lenses or detached remnants of beds of foliated argillite and cherty argillite that locally occur within the unit. The graywacke is relatively resistant to weathering and generally underlies the more prominent hills in the project area. Where exposed, the rock is fresh to slightly weathered and strong. Moderately to widely spaced, partly opened to very tight joints are typical on vertical exposures of the graywacke. The massive argillite is a strongly indurated, dark gray to dark greenish gray, weakly metamorphosed siltstone to very fine grained sandstone. It is a fine-grained eq~ivalent of the graywacke and has similar rockmass properties. Exposures of this unit are fresh to slightly weathered, massive and typically have moderately to widely spaced joints. A weakly metamorphosed tuff was identified in a thin section from a sample taken from a location just northwest of hill 2070. Tuff was also identified in a thin section of a sample of graywacke taken from a location 5-5 midway between hill 2070 and the surge tank. The COE classified a thin section sample from their boring DH-11 as a "volcanic graywacke". It is difficult to make any firm statement regarding the distribution of the tuff because it can only be positively identified in thin section. It appears to be present within both the graywacke and the massive argillite. Twenty-two thin sections of various rock types, many selected because of their anomalous megascopic appearance, were examined with only two samples identified as tuff, and only two field occurrences were noted. It is likely that it is a minor component of the overall rock mass. Thin section analysis (see Figure 7 .4-7) indicates that it was deposited in water and could simply be considered a sub-type of the graywacke, that is, a "volcanic graywacke" as classified by the COE. The foliated argillite and foliated cherty argillite are differentiated solely on the abundance of chert within the rock. For this evaluation we have considered the argillite to be 11 chertyn if interlayered.and lenticular chert exceeds about 10 percent of the outcrop. The argillite is a dark gray to black, weakly metamorphosed siltstone and very fine sandstone. Chert occurs throughout the rock (in various percentages) typically as discontinuous layers and elongated nodules. Foliation is predominantly a shear foliation that has developed along the regional structural trend. Jointing is not frequently expressed in outcrops of the foliated argillite but where present the joints are typically widely to very widely spaced and very tight. Outcrops of the foliated argillite are fresh to slightly weathered. Two dacite dikes were observed in the map area. One is known from a single small outcrop of the exit portal, whereas the other is exposed to the east near the middle of the tunnel alignment. The eastern dike trends northeasterly to easterly across the regional structural trend, cutting across both graywacke and argillite units. It is about 30 to SO feet wide and can be traced to the northeast of the tunnel alignment where it dips nearly vertically. The dacite is a light greenish gray, porphyritic rock, is typically slightly weathered in outcrop, and appears to be slightly more resistant to erosion than the units it intruded. It is a massive rock with S-6 widely spaced, very tight joints. Its strength and other rockmass properties appear to be similar to the massive argillite and graywacke. Overburden ranges from a few tenths of a foot to 15 or more feet thick and consists of sands and silts covered with a thick mat of organic, mossy material. In some cases the organic material is the only covering. The unconsolidated sediments in the Bradley Lake area consist of glacial outwash and till, river and tidal flat deposits, and talus rubble. These· sediments are dominated by clasts of graywacke and argillite which vary depending on the composition of the source area. The tills and talus deposits are composed of gravel to boulder size clasts of subangular to angular graywacke and flaky gravel to cobble size argillite. These clasts are in a matrix of gravel, sand, and silt. Graywacke dominates the coarse fraction of these deposits, while the argillite appears to dominate the fine gravel and sand-size fraction. 5. 2. 2. 4 Structure The most prominent structural elements in the project area are the pervasive, closely-spaced shear foliation in the argillites, and the complex structural distribution of bedrock units. The area is complexly deformed by the pervasive shearing, by two major fault zones, and by numerous smaller faults in a variety or orientations. The significance of folding in the project area is not apparent because; a) well-defined marker horizons and bedding are lacking, b) vegetative cover obscures much of the rock, and c) the bedrock units are complexly distributed. The Bradley River and Bull Moose faults are the most significant faults in the project area. These faults zones are high-angle structures that trend N5°E to N20°E and extend for at least a few miles outside the project area. Several smaller high-angle faults and a few low-angle faults have also been identified in this and previous studies. The high-angle faults tend to fall into two general sets: those subparallel to the Bradley River and Bull Moose .fault zones and those at about 90° to these larger structures. Only a few minor low-angle faults have been noted. 5-7 , Jointing is present in all the rocks in the area although it is generally best developed in the graywacke. Joint orientations are highly variable. Joint surfaces are generally relatively smooth, and range from very tight to open cracks about 2 inches wide. Joint spacing is highly variable, ranging from a few inches in local areas to several tens of feet in other areas. Generally at least three joint sets at high angles to one another can be found, resulting in a blocky rockmass. A number of well developed linear topographic depressions cross the project area. A few of the most pronounced and continuous of these lineaments are recognized as faults, but the origins of many of the others are not readily apparent. Most of the lineaments are probably the surface expression of either faults or series of closely spaced joints. Rock exposures along the lineaments are commonly absent, and colluvial or glacial deposits obscure the evidence needed to determine the nature of these features. 5. 2. 3 Seismotectonic Setting The primary cause of seismic activity in southern Alaska, including the site area, is the stress imposed on the region by the relative motion of the Pacific and the North American lithospheric plates at their common boundary. The Pacific plate is moving northward relative to the North American plate at a rate of about 6cm/yr. causing the underthrusting of the Pacific plate. This underthrusting results primarily in compressional deformation which causes folds, high-angle reverse faults, and thrust faults to develop in the overlying crust. The boundary between the plates where the underthrusting occurs is a northwestward-dipping megathrust fault or subduction zone. The Aleutian Trench marks the surface expression of this subduction zone and is located on the ocean floor approximately 185 miles south of Bradley Lake. The orientation of the subduction zone is inferred along a broad inclined band of seismicity, referred to as the Benioff Zone, that dips northwest from the Aleutian Trench, and is approximately 30 miles beneath the Bradley Lake Site. Historically (1899 to date), eight earthquakes ranging between 7.4 and 8.5 Richter magnitude have occurred within 500 mi of the site. 5-8 12eat earthquakes (surface wave magnitude M 8 or greater) and large s earthquakes (greater than M 7) have occurred historically throughout the s region and can be expected to occur in the future. Bradley Lake is situated on the overriding crustal block above the subduction zone and between the Castle Mountain fault to the north and the Patton Bay-Hanning faults to the southeast on Montague Island; all of these faults have documented Holocene or historic surface ruptures. Because of the active tectonic environment, activity is probable on other faults, such as those found near or on the project site, which are also located in the overriding crustal block and between the known active faults mentioned above. Two faults of regional extent occur at or near the site. The Border Ranges Fault trends southwest beneath Kachemak Bay and the Eagle River Fault crosses the southeastern portion of Bradley Lake at about the same trend. \fuile no direct evidence or recent activity along these faults is known in the site area, recently-defined data indicates recent activity on the Eagle River Fault near Eklutna (125 mi NE of the site.) Given the tectonic setting, it is reasonable to consider these faults potentially active. In addition to the nearby regional faults, the site is crossed by two large local faults, informally called the Bradley River Fault and the Bu~l Moose Fault, and a number of probable smaller faults. The dominant trend is northeasterly, paralleling the regional trend. The larger local faults, particularly the Bradley River, are probably capable of independent earthquake generation while any of the local faults could probably move in sympathetic response to earthquakes generated by the regional faults. It is therefore concluded that the site will probably experience at least one moderate to large earthquake during the life of the proposed project. The possibility of ground rupture exists but is much less subject to prediction. 5 . 2. 4 Seismic Design Based on previous studies and evaluations, supplemented by data and considerations of this study, it is recommended that design maximum 5-9 earthquakes include a magnitude M 8.5 at 30km directly below the site and s a magnitude M 7.5 on either the Border Ranges or Eagle River Fault at s their closest approach to the site (less than 3km or 1. 8 mi). Possible ground displacement is addressed in the final portion of this section. Seismic exposure analysis, for a 100 year duration, for the site yields the results tabulated below: Exceedance Probability 50% 30% 10% Maximum Horizontal Acceleration 0.37g 0.43g 0.58g The controlling feature for this evaluation is the Aleutian Megathrust; in its absence, acceleration levels would be reduced about 0.10 to 0.16g. The values given above are considered to be as accurate as available data allows. It m~st be recognized that historical data, except for very large events, is sparse beyond about 100 years ago and instrumental data is available for less than the past 75 years. Recommendations for probable design acceleration values, given below, are based on general economic considerations for the project and on the consideration that seismic failure of even a major project facility would not result in a life-threatening situation for any existing or projected population. All major project facilities will be founded on or excavated in rock and design acceleration values given below-are for horizontal acceleration in rock. o Dam -0. 75g. Loss of the dam for the operational project would mean temporary loss of the project and a major reconstruction expenditure. However, by the very nature of the dam type selected, although it might be damaged and leak, the dam would still remain in place and retain the reservoir impoundment. The acceleration of 0. 75g corresponds to an M s 7.5 shallow crystal event with a recurrence probability of less than 10% in 100 years. This envelopes the more probable megathrust 5-10 event of M 8.5 s (approx. 0 .55g) with a 100 -year recurrence probabilility of 10%. This is a relatively short significant duration event (25 sec) and, as such, has less effect on massive structures such as a dam. Current studies at the dam site have not revealed any structures with potential for ground displacement. o Intake Structure/Gate Shaft -0. 75g. These structures are considered to be critical installations with respect to seismic shock resistance. Seismically-induced damage to the intake channel (rockfall) or the dam (leakage) would not prevent water from entering the power shaft/tunnel system should the closure gate become inoperative. The diversion/low-level outlet facilities are at an elevation above that of the power tunnel intake and could not be used to lower the water level below that of the intake. Reconstruction under such conditions could be costly. A design level of 0. 75g represents a conservative value, since it is based on the postulated shallow crustal fault event. However, since the gate shaft and intake structure integrity are significant during and after a major seismic event and represent a moderate expenditure, in comparison to overall cost, it is recommended that the maximum acceleration value be considered in final design for these structures. o Power Tunnel, including Steel Liner/Shafts No acceleration value assigned. Fully embedded installations tend to react in concert with the surrounding rock mass, unless actual rupture and displacement of the rock mass occurs. It has been assumed that the Bradley River and Bull Moose Faults are capable of independent earthquake generation, implying surface and subsurface rupture potential, and are also capable of rupture in response to events on adjacent, larger faults. Thus, the largest potential displacements, up to 300 em (10 feet) have been postulated on these faults; the probability is very small for this case. Smaller faults are not considered capable of independent earthquake generation and any displacement on them would occur as a response to forces produced by events on larger faults. The range of potential displacement for minor faults is assessed as from 20 em (0.6 feet) to 100 em (3 feet). Should displacement occur, it is anticipated 5-11 The probability of this event is not to exceed about 120 em (4 feet). in the range of about 2X10-4 for a 100 year interval. The most probable event (in 100 years) has been es.timated at 4X10 -3 with a displacement of only 20 em (0.6 feet). It is considered to be impossible to design to withstand or accommodate rock mass rupture. In the absence of safety-related considerations, it is recommended that no consideration other than those consistent with normal tunnel design be applied. There are undoubtedly a number of minor faults which also intersect the tunnel facilities; no special design features are necessary for reasons stated above. Should rupture occur, provisions for access for repair equipment has been included in the form of a roll-out section in the steel penstock, adjacent to the powerhouse. A tunnel bypassing the offset section could then be driven. o Powerhouse -not to exceed 0.35g. There is a 50% chance that the site win experience horizontal bedrock acceleration up to about 0. 35-0. 4g during a 100 year interval. This represents a commonly-accepted level for an operating-basis earthquake. An earthquake design for 0. 35g, using normally acceptable stresses and operating requirements commonly results in the ability of the structure(s), equipment and systems to safely sustain higher earthquake accelerations at increased but 0 acceptable stress levels and operating extremes. If a higher recurrence factor is considered acceptable during final design, an acceleration value less than 0. 35g could be utilized. The depth of bedrock was the primary geotechnical concern at the powerhouse site. A hand-dug test pit confirmed the presence of bedrock at shallow depths. Also, faults, and even joint swarms, which have strong topographic expression throughout the site area, were not found to occur at the powerhouse site. If faulting is present, it is minor. Given the above condition$, it is recommended that the powerhouse, and ancillary facilities required .for continued operation, be designed for this level of shock. Other Project Facilities -not to exceed 0.35g. These include such facilities as accommodations for operation personnel, barge access 5-12 channel and basin, shop, warehouse, oil and water storage tanks, structures housing sluice and intake gate controls, and bridges. For final design purposes, it may be desirable to evaluate the possible costs of repairs as opposed to initial construction costs for various levels of seismic design. Many structures of conventional design and proper construction can withstand accelerations in the 0. 2-0.35 range while sustaining only moderate, repairable damage. If a higher recurrence factor is considered acceptable during final design, a design value of less than 0. 35g could be utilized. Given a probable recurrence interval of several tens of years, it may not prove economic to design non-critical facilities to totally withstand the effects of major seismic events. It is also considered that minor project facilities cannot practicably be designed to accommodate ground rupture. It should be noted that failures in soils such as those found in and immediately adjacent to Kachemak Bay are practically unavoidable at the peak accelerations considered for this site. Such failures ~~~; Gould-result ci.n slope failures in the access-cha.."llel and barge "Qas in side slopes, and differential settlement of the air strip. These are possibilities which must be considered in evaluation of the project. 5.3 HYDROMETEOROLOGY 5.3.1 General The COE conducted extensive studies of the hydrologic and climatologic characteristics of the Bradley Lake drainage basin. The results of their studies are contained in their "Design memorandum No. 1, Hydrology," dated June 1981, and "General Design Memorandum No. 2, Volumes 1 and 2," dated February 1982. In general, all data as reported therein, except as described below, provided the basis for developing the criteria used in the present study. The following sections summarize the important hydrologic parameters gathered by the COE and SWEC' s subcontractor R&M Consultants, Inc. (R&M), and utilized in this study. Where appropriate, summaries are provided to describe changes to the COE's baseline data or to indicate where additional future data development and studies are required. 5-13 5. 3. 2 Basin Description The Bradley Lake Project is located within the Kenai Mountains approximately 27 miles northeast of Homer, Alaska. The project utilizes water stored in Bradley Lake which is situated about 1, 080 feet above Kachemak Bay in an ice-free subalpine valley. The basin above the lake consists of rugged and precipitous rocky slopes interspersed with various forms of low vegetation and other growth. Higher elevations are characterized by barren slopes with most of the land features carved from the various glaciers within the basin. The Nuka and Kachemak glaciers are the two largest glaciers providing runoff into Bradley Lake. The drainage area above the lake outlet is 56.1 square miles of which approximately 36 percent is covered with glaciers. The Middle Fork diversion facility which will divert streamflow into a tributary of Bradley Lake is located about a mile north of Bradley Lake. The physiographic features of the basin are similar to the Bradley Lake basin. The drainage area above the point of diversion is 10.1 square miles with about 29 percent of the basin covered by glaciers and permanent snowfields. 5. 3. 3 Climatology 5.3.3.1 General The Bradley Lake basin is influenced by a maritime climate with associated cool summer and ~moderate winter temperatures. Average annual temperature has been estimated as 35°F. Fog, rain, and clouds are characteristic of the basin with high winds frequently occurring. Until 1980, no climatological records were available for the Bradley Lake basin. Climatological data used in previous studies were developed through correlation and regression analyses (Jf nearby basins on the Kenai Peninsula. The following summarizes the results of these studies. 5-14 5. 3. 3. 2 Precipitation Precipitation within the basin is greatest during the August through December period with the smallest amounts occurring from January through July. Most storms occur in the fall and early winter months and move in a northeasterly direction from Kachemak Bay with the greatest amounts of precipitation occurring in the higher elevations of the basin (1. 5 inches per hour). 5 . 3 . 3 . 3 Snow Snowfall ,is greatest in the upper elevations of the basin which contributes materially to the volume of the larger glaciers producing runoff during the summer months. First snows usually occur in October and extend through early May with the heaviest accumulation occurring during December and January. 5.3 .3 .4 Ice Lake ice thickness of 17-28 inches was estimated by the COE and should have minimal impact on project operation. Future studies should address the effects of ice formations near the power conduit intake channel and its impacts on wildlife migratory patterns in the upper reaches of the reservoir. Ice and snow accumulations on project structures and the transmission lines will also have to be addressed, however, these effects are not insurmountable from a design standpoint. Ice accumulations within Kachemak Bay and the areas subject to tidal influences are also expected to be minimal with no affects on project operations or access. 5 . 3 . 3 . 5 Wind Wind data at the site has been gathered since August 1979. The COE' s analysis of the limited data indicates that highest winds occur from October through April with several speeds exceeding 70 MPH during this period. The 100 year return period speed has been estimated as 115 MPH in the area with the predominate direction of the winds toward the northwest. 5-15 Wind speed, direction, duration, frequency, and seasonal distribution are the major factors which will have to be reviewed in future studies as all these factors could be significant in the design of the various project structures. The wind criteria developed in the final design studies will determine the spectrum of various wave characteristics to be expected in Bradley Lake at the damsite by which final freeboard requirements for the main dam will be set. More directly, wind characteristics will determine the criteria to be used in final design of the transmission lines, powerhouse superstructure, and other structures. The present study did not analyze these wind characteristics in detail due to the limited amount of data available. Should final engineering and design studies proceed in the near future, the wind data developed at that time will be thoroughly reviewed. 5.3.4 Hydrology 5.3.4.1 Runoff The runoff response from precipitation in the Bradley Lake watershed is influenced greatly by the geologic conditions of the basin. Due to the limited amount of soil cover overlying bedrock, almost all of the runoff reaches the streams and tributaries of the basin with very little flow going into groundwater storage. Mean annual runoff exceeds 90 percent during the May through October period which is characteristic of the basin's maritime influence. Runoff contributions from snowmelt usually occur in May and June, with intense rainfall contribution to the maximum runoff during August through October. Glacier contributions to runoff are dependent on seasonal and long term temperature and precipitation variation. Their affects are discussed further on and a detailed discussion can be found in R&M's report included as Appendix B of this report. 5-16 5 . 3. 4. 2 Streamflow Streamflow records at the Bradley Lake outlet are available from October 1957 to the present, however, records for the Middle FoLk flows and Upper Bradley River were not started until October 1979. As stated above, higher streamflows occur in the May through October period as a result of snowmelt and intense rainstorms during the summer and fall periods. Maximum mean daily discha~ges during this period have exceeded 5,000 cfs. Typical low flows during the November through April period range from 20 cfs to about 250 cfs with higher flows seldom exceeding about 750 cfs in November. Flows in the drier December through April periods seldom exceed 20 to 75 cfs. 5 .3.4.3 Streamflow Adjustments --Po~ver Studies Adjustments to the historical streamflow records (October 1957 through September 1982) were required to reflect potential future inflows to Bradley Lake for use in predicting expected power and energy generation from the project. A detailed description of the methodology used to establish the adjusted streamflows is included in Appendix B. Only a summary of results is presented herein. Initial streamflow adjustments of the historical records were made to reflect switching of the Nuka glacier runoff from the Nuka River to the Bradley River after 1970. The results of this analysis indicate that the COE' s estimate of flow adjustment during this period was too conservative by a factor of about 50 percent. Instead of the 46 cfs annual runoff added to the 1957 through 1970 period, this most recent analysis indicates that an additional 43 cfs of streamflow over the COE's estimate would have been available. The additional 43 cfs was therefore added to the COE's tabulated flows over the 1957-1970 period and distributed on a monthly basis in accordance with the pattern estimated by the COE. The revised monthly flows are shown in Table 5.3-1 and an annual flow-duration curve is presented in Figure 5. 3-1. 5-17 5.3.4.4 Middle Fork Streamflows Middle Fork monthly streamflows were developed on the basis of the above adjusted Bradley River Streamflows (Table 5. 3-1) for the period of the Bradley Lake record. Because an additional two years of monthly flow data at the Middle Fork Diversion were available since the COE' s analysis, the Middle Fork flows presented herein represent a refinement over that used by the COE. A description of the methodology used to establish the Middle Fork flows is included in Appendix B. Table 5. 3-2 shows the adjusted monthly flows used in this study and Figure 5. 3-2 shows the mean annual flow duration curve. 5.3.4.5 Lower Bradley River Streamflows Monthly flows were also developed for the Lower Bradley River for the unregulated portion of the drainage below the Middle Fork Diversion and Bradley Lake outlet. Tnese flows are ·shown on Table 5. 3'-3. --The purpose of these estimates was to determine the contribution that these flows would have in meeting the target flows established by the instream flow assessments for aquatic habitat enhancement. Although these flows are not used directly in determining the potential power output of the project they do contribute in minimizing the amount of water which may have to be diverted out of Bradley Lake to satisfy minimum instream flows for aquatic habitat. An annual flow duration curve for the above conditions is shown in Figure 5. 3-3. 5.3.4.6 Bradley River Glacial Adjustments To account for possible future changes in the flow regime of the Upper Bradley River due to glacial influences, studies were conducted to determine their affects on runoff production. Aerial photos of the glaciers within the basin were used in estimating an equivalent water thickness loss of 14 + 18 feet averaged over the glaciers between the period 1952 and 1979. Although the glaciers have retreated in this time period, the upper mass of the glaciers has actually increased, which is consistent with other glaciers in the area. 5-18 The total loss of water equivalent in the glaciers was then distributed over the previously adjusted historical Bradley Lake streamflow record using a runoff precipitation model which was calibrated for other glaciers of Alaska. Monthly distribution of the annual loss was distributed to the months of June through September using a thawing degree-day index. The revised streamflow record which represents a condition where the glaciers are neither gaining nor loosing water from storage in any given year is shown in Table 5.3-4. An annual flow duration curve for the above mass balance adjustments is shown in Figure 5.3-4. The above flow scenario represents a condition on the conservative side in terms of available streamflow for power production. Should climatic conditions similar to the historical records occur in the future then flows in Table 5.3-4 would be representative. However, a small change in climatic conditions in the future could cause the glaciers to return :to a state similar to that at the beginning of the period of record. In q,rder to reflect this possibility, Table 5. 3-5 has been prepared to indicat~~ the streamflow record wherein year-to-year variation in glacial mass caused by differences in climatic conditions occurs. This represents a condition wherein only the trend of long term glacier wasting is removed. The annual flow duration curve for this record is shown in Figure 5.3-5. A detailed description and methodology of the above glacial adjustments to streamflow can be found in Appendix B. 5.3.4. 7 Floods Flood peaks usually occur between June and September with most floods in early summer caused by snowmelt and those in August and September from rainfall. Characteristics of the geologic conditions of the basin, most flood hydrographs are characterized by typically skewed distribution of discharge with a fairly steep rising limb and asymmetric recession limb. The COE analyzed the flood characteristics of the basin and developed a flood frequency curve based on the historical records. Their analysis included adjustments of the annual flood peaks during the 1958 through 1970 5-19 period to account for the Nuka Glacier runoff switching from the Nuka River to the Bradley River. It has been shown above that their estimate of this adjustment was too low which would tend to underestimate the discharge for a given return period flood. In addition, it appears that their analyses used the recorded discharges at the lake outlet which would be lower than the actual inflow into the Lake due to the regulation effects of surcharge storage. However, it has just recently been found (August 1983) that the Nuka Glacier runoff has switched back again to the Nuka River with a diversion of flow between the Nuka and Bradley Rivers similar to that which occurred in the 1958 through 1970 period. It therefore appears that the COE's estimate of the flood frequency is acceptable for the runoff conditions now being experienced in the basin. Should this condition continue into the construction period of the Project, it would obviously reduce the expected flood peaks which the diversion tunnel would have to pass. A small diversion dike or an improvement to the outlet channel flowing to Bradley Lake will have to subsequently be developed near the termirnis of Nuka. Glacfer to ins-ure th.e glacier runoff is directed into Bradley Lake, as all power and energy values reported herein are based on this condition. 5.3.4.8 Probable Maximum and Standard Project Flood The COE conducted a fairly extensive study characteristics of the Bradley Lake drainage basin of in the hydrologic determining the Probable Maximum Flood. The methodology and approach used by the COE was reviewed by SWEC and appears thorough. The Probable Maximum Flood (PMF) inflow was determined for Bradley Lake both with and without Middle Fork Diversion, however, it was shown that the Middle Fork Diversion's contribution to the peak PMF inflow was only about equal to its maximum diversion capacity of about 450 cfs. The PMF study conducted by the COE is discussed in their "Design Memorandum No. 1 11 entitled "Hydrology" dated June 1981 and in "Design Memorandum No. 2 11 , "General Design Memorandum" dated February 1982. However, the results reported in these references are not the same. The COE stated that the peak flow of the Standard Project Flood (SPF) reported in their design 5-20 memorandum was about equal to the estimated 100 year flood. Because the Probable Maximum Precipitation (PMP) used in deriving the SPF was a fixed ratio (50%) of the PMP used in deriving the PMF, the streamflow routing parameters were revised to increase the peak flood discharge of the PMF and the SPF. The revised PMF and SPF hydrographs were therefore included in the COE later issued General Design Memorandum No. 2. Plate 18 shows the COE's updated hydrographs which were used in the present study to size the spillway. 5. 3. 4. 9 Sedimentation and Evaporation The COE 's analysis of sedimentation in both Bradley Lake and Middle Fork indicated suspended sediment concentrations were so low so as not to present any long term sedimentation problems. Evaporation from the lake surface during project operation was also found to be minimal. Since the historical streamflow records used in developing the power generation estimates already reflect the effects of evaporation, no adjustments to recorded streamflows are required. 5 . 4 SURVEY CONTROL The project datum used in this report is based ·on Alaska State Plane Coordinate System Zone 4, which is referenced to the North American datum of 1927 (NAD 27 /Clark Spheroid of 1866). The project vertical datum is based on an assumed datum for this project which was initiated by using the scaled elevation of control point referred to as JEFF at 26.24 feet. Later observations by National Oceanic and Atmospheric Administration (NOAA) placed the local project datum origin for Mean Sea Level (MSL) 4. 02 feet lower. The Mean Lower Low Water datum (MLLW) origin is 9. 61 feet lower than MSL origin or 13.63 feet lower than the project datum origin. The differences between project elevations referenced and used by this study and MSL or MLLW can be equated as follows: MSL elevation = MLLW elevation = Project Elevation+ 4.02 feet. Project Elevation+ 13.63 feet. 5-21 Recent field surveys performed by R&M in conjunction with field study efforts showed further horizontal and vertical discrepancies between previously published coordinate values of monumented stations as discussed in Appendix B. Horizontal shifts varying from 0. 502 feet to 1. 68 7 feet feet were noted. Similarly vertical position shifts of + 1.170 feet to + 4. 719 feet were determined. The study recognized these discrepancies. However, since the relative value of elevations would be within i 2.5 feet, it was decided to only consider the 4. 02 feet correction for reference in the study. Future efforts must include a new, stronger control network for project use in definitive engineering and design work. In addition to the above discrepancies, it was also observed during the course of field work that certain areas of the topographic maps utilized in the COE study were not accurate. Although the discrepancies would not impact the results of this study, it is recommended that more accurate maps of selected areas be prepared for future engineering-design. 5-22 :tear 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980* 1981* 1982* * Recorded BRADLEY RIVER FLOWS AT LAKE OUTLET ADJUSTED. FOR NUKA GLACIER SWITCH DRAINAGE AREA = 56.1 SQUARE MILES MONTHLY,ANNUAL MEAN DISCHARGE, IN CUBIC FEET PER SECOND Oct Nov Dec Jan Feb Mar Apr Hay Jun Ju1 Aug Sep 175 577 111 79 42 32 74 389 1' 378 1,410 1,692 446 275 102 60 33 25 22 33 308 1,055 1,052 1,041 419 187 94 60 39 35 24 33 593 900 1,166 1,094 572 249 144 179 199 107 42 30 436 948 1,361 1,166 1,258 347 116 71 55 31 22 39 177 852 1,101 881 500 269 317 127 113 87 67 45 231 781 1,512 1,481 1,228 562 94 108 75 63 40 33 87 841 1,227 1,597 1,151 477 140 85 64 50 55 75 131 655 1,153 1,227 1,756 595 165 10 39 32 31 41 150 966 1,146 2,162 1,819 525 64 43 35 31 29 36 253 910 1,241 1,562 1,802 231 224 136 99 91 105 62 307 739 1,140 1,287 513 211 13 41 35 35 34 43 310 1,673 1,543 1,065 723 1,900 211 239 118 116 109 103 331 895 1' 324 1,410 740 197 382 76 45 36 31 31 115 641 1,394 1,262 507 376 108 55 32 20 17 17 141 517 1,172 1,378 1,019 413 123 56 34 26 24 28 128 600 918 870 908 575 173 50 32 23 19 23 227 551 860 1,000 1,501 346 224 112 55 43 34 30 355 1,035 1,068 864 850 424 118 52 39 32 26 41 206 813 1,107 1,153 1,293 420 414 312 326 306 178 119 354 995 1,653 2,049 646 407 70 37 34 40 42 56 291 755 1,081 1,182 959 572 161 104 43 30 27 31 290 712 1,004 1,883 1,357 1,173 411 85 67 81 74 58 326 936 1' 332 1,304 897 779 150 110 233 160 170 310 788 908 1,490 1, 643 885 298 251 98 52 73 45 37 138 677 1,107 904 1,780 Annual 587 371 403 512 351 525 494 490 604 506 415 489 631 396 406 346 421 420 443 652 415 521 564 640 456 L_ ________ ---..,... ____ __...;. _________ __.;,. __ TABLE 5.3-1 Year Oct 1958 59 1959 34 1960 23 1961 31 1962 35 1963 34 1964 42 1965 48 1966 45 1967 53 1968 29 1969 35 1970 143 1971 25 1972 38 1973 41 1974 43 1975 43 1976 42 1977 42 1978 41 1979 43 1980** 98 1981** 51 1982** _].§. Average 46 MIDDLE FORK FLOWS AT DIVERSION DAM (Based on ratios developed for Bradley River Flows adjusted for Nuka Glacier Switching*) Nov Dec Jan Feb Mar Apr May Jun Jul 64 6 6 5 4 4 14 126 214 10 8 4 4 2 4 14 93 113 9 8 4 4 2 4 21 90 152 9 9 15 9 5 4 15 85 204 12 8 6 5 2 4 10 85 121 35 6 8 7 5 4 11 78 227 9 12 6 8 5 4 5 84 160 8 10 7 6 4 4 . 7 66 150 10 8 4 5 4 4 8 87 149 6 5 4 5 3 4 11 91 161 25 7 7 7 7 4 14 74 148 7 5 4 4 4 4 14 151 231 13 12 9 9 8 4 12 90 172 42 9 5 5 4 4 6 64 209 11 7 4 3 2 4 8 52 152 7 7 4 4 2 4 7 60 101 10 6 4 3 2 4 10 55 95 25 6 6 5 4 4 12 93 117 12 7 4 5 2 4 9 81 122 46 16 24 24 12 4 12 90 248 7 5 4 5 5 4 13 76 119 10 12 5 5 3 4 13 71 110 35 9 5 5 4 4 14 85 208 8 5 17 9 7 4 24 92 211 .21 _JJ. _7 _9 _5 4 8 _.21_ 144 19 8 7 6 4 4 12 83 162 * Nuka Glacier Basin switching assumed to occur after 1970. ** Recorded monthly averages • Aug Sep 188 47 127 43 137 60 157 107 110 53 163 147 176 138 166 149 238 155 172 153 174 54 133 76 190 78 170 53 186 122 109 109 125 128 108 102 144 110 225 68 160 115 207 115 180 115 183 88 113 136 162 101 ..___ ________ TABLE 5.3-2 ESTIMATED AVERAGE MONTHLY FLOW LOWER BRADLEY RIVER Year Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep 1958 125 190 40 36 23 28 65 113 182 103 63 53 1959 51 50 24 32 23 19 29 110 177 99 52 50 1960 52 5.1: 29 36 25 20 28 115 186 104 58 63 1961 52 42 41 75 37 22 44 112 181 104 59 99 1962 55 53 27 34 24 22 39 115 185 99 55 38 1963 49 55 25 44 61 90 30 104 167 102 47 54 1964 61 20 24 38 29 16 13 149 240 115 61 50 1965 60 71 27 23 15 29 40 115 186 120 54 88 1966 59 23 13 27 26 18 24 125 202 113 74 94 1967 75 57 34 35 21 13 16 107 172 102 56 69 1968 48 123 48 45 32 18 38 105 169 94 41 33 1969 42 27 15 24 17 13 16 87 141 91 38 30 1970 270 58 46 49 45 52 43 94 152 98 46 47 1971 47 76 22 29 21 16 16 112 180 104 67 48 1972 50 33 29 39 27 18 17 71 114 87 34 58 1973 64 32 18 13 11 10 16 66 148 92 35 43 1974 41 30 22 17 13 12 21 97 135 53 22 52 1975 66 59 29 16 13 11 11 80 213 139 40 66 1976 80 30 20 15 13 11 22 87 184 106 35 117 1977 105 100 74 107 80 41 33 114 202 144 97 36 1978 107 32 14 14 15 12 15 99 180 82 34 41 1979 133 56 52 28 18 13 27 96 151 82 69 39 1980 156 175 52 23 36 24 29 127 215 131 104 76 1981 134 45 28 112 61 52 42 205 160 120 61 45 1982 ....2§. ~ 2. ...1:2. ~ 20 18 _2.2. 139 ..11 ~ --22 Average 82 62 32 37 29 24 28 107 174 102 53 60 * Unregulated area below Bradley Lake damsite and Middle Fork Diversion. ~----------------TABLE 5.3-3 Year 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 BRADLEY RIVER FLOWS AT LAKE OUTLET ADJUSTED FOR NUKA SWITCH AND GLACIER BALANCE CHANGES DRAINAGE AREA = 56.1 SQUARE MILES MONTHLY AND ANNUAL MEAN DISCHARGE, IN CUBIC FEET PER SECOND Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep 775 577 111 79 42 32 74 389 1,430 1,470 1,750 475 275 102 60 33 25 22 33 308 1,070 1,080 1,070 436 187 94 60 39 35 24 33 593 990 1' 320 1,230 651 249 144 179 199 107 42 30 436 1,160 1,650 1,440 1,440 347 116 71 55 31 22 39 177 937 1,220 1,000 541 269 317 127 113 87 67 45 237 560 1,120 1,090 944 562 94 108 75 63 40 33 87 769 1,140 1,510 1,090 477 140 85 64 50 55 75 131 625 1,100 1,180 1,710 595 165 70 39 32 31 41 150 596 660 1,690 1,480 525 64 43 35 31 29 36 253 820 1,110 1,430 1, 730 231 224 136 99 91 105 62 307 585 929 1,060 416 277 73 41 35 35 34 43 310 1,080 820 466 308 1,900 211 239 118 116 109 103 331 771 1,170 1,250 660 197 382 76 45 36 31 . 31 115 862 1,750 1,670 710 376 108 55 32 20 17 17 141 484 1,120 1, 320 987 413 123 56 34 26 24 28 128 760 1,150 1,090 1,030 575 173 50 32 23 19 23 227 309 530 652 1,250 346 224 112 55 43 34 30 355 1,280 1,450 1,250 1,090 424 118 52 39 32 26 41 206 777 1,050 1,100 1,260 420 414 312 326 306 178 119 354 1,350 2,100 2,550 927 407 70 37 34 40 42 56 291 670 966 1,050 889 572 161 104 43 30 27 31 290 739 1,050 l' 930 1, 390 1,170 411 85 67 81 74 58 326 936 1' 332 1' 304 897 779 150 110 233 160 170 310 788 908 1,490 1,643 885 ~ 298 251 98 52 73 45 37 138 677 1,107 904 1,780 Annual 604 379 441 591 382 417 468 475 465 510 358 295 588 495 391 407 324 523 428 784 382 533 564 640 456 '---------------------------TABLE 5.3-4 Year 1958 1959 1960 1961 1962 1963 1964 .1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980* 1981* 1982* *Recorded BRADLEY RIVER FLOWS AT LAKE OUTLET ADJUSTED FOR NUKA SWITCH AND FOR TREND OF GLACIER WASTING DRAINAGE AREA = 56.1 SQUARE MILES MONTHLY AND ANNUAL MEAN DISCHARGE, IN CUBIC FEET PER SECOND Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep 77 577 111 79 42 32 74 389 1, 340 1, 360 1,640 422 275 102 60 33 25 22 33 308 1,030 1,020 1,010 402 187 94 60 39 35 24 33 593 879 1,130 1,060 553 249 144 179 199 107 42 30 436 915 1, 320 1,130 1,230 347 116 71 55 31 22 39 177 833 1,070 853 491 269 317 127 113 87 67 45 237 765 1,480 1,450 1,210 562 94 108 75 63 40 33 87 813 1,190 1,560 1,130 477 140 . 85 64 so 55 75 131 635 .1,120 1,193 1,720 595 165 70 39 32 31 41 150 942 1,110 2,130 1,800 525 64 43 35 31 29 36 253 885 1,200 1,520 1,780 231 224 136 99 91 105 62 307 720 1,110 1,260 501 277 73 41 35 35 34 43 310 1,650 1,520 1,040 708 I 1,900 211 239 118 116 109 103 331 858 1,280 1, 360 H6 197 382 76 45 36 31 31 115 619 1, 360 . 1,220 487 376 108 55 32 20 17 17 141 500 1,140 1, 350 1,000 413 123 56 34 26 24 28 128 576 884 838 890 575 173 50 32 23 19 23 227 534 837 975 1,480 346 224 112 55 43 34 30 355 1,010 1,020 821 821 424 118 52 39 32 26 41 206 792 1,070 1,120 1,270 420 414 312 326 306 178 119 354 947 1,590 1,980 608 407 70 37 34 40 42 56 291 888 1,460 1,610 868 572 161 104 43 30 27 31 290 651 1,060 862 1,750 1,173 411 85 67 81 74 58 326 936 1, 332 1, 304 897 119 150 110 233 160 170 310 788 908 1,490 1,643 885 298 251 98 52 13 45 31 138 677 1,107 904 1,780 Annual 573 363 394 500 344 517 484 480 595 536 408 482 618 386 398 337 414 408 434 634 407 509 564 640 456 ..____---------------------------TABLE 5.3-5 ___, (I) I&. (.) . 3: 0 ...I I&. ...I < :::;) z z < w ~ < a: w > < • 500 400 300 200 % EXCEEDANCE ANNUAL FLOW DURATION BRADLEY LAKE OUTLET ADJUSTED FOR NUKA GLACIER SWITCH ONLY .___---------FIGURE 5.3-1~ en u. (.'I . s: 0 ...1 u. ...1 < ~ z z < w 0 <C a:: w > < 50 40 30 % EXCEEDANCE ANNUAL FLOW DURATION MIDDLE FORK AT MIDDLE FORK DIVERSION DAM ..___--------FIGURE 5.3-2 ~ 100 90 80 Cl.l 70 u. (,) . 3: 60 0 -' u. ...1 < ~ 50 z z < w 0 40 < a: w > < 30 20 10 0 0 10 20 30 40 50 60 70 % EXCEEDANCE ANNUAL FLOW DURATION LOWER BRADLEY RIVER 80 90 100 '-----------FIGURE 5.3-3 ____. en u. (.) . 3: 0 ... u. ... < ::I 2 2 < w c:J < a: w > < 500 400 300 % EXCEEDANCE ANNUAL FLOW DURATION BRADLEY RIVER WITH GLACIER MASS BALANCE ADJUSTMENTS ------------FIGURE 5.3-4 en u. (J . 3: 0 -' u. -' c( :::::1 z z c( w (!I c( a: w > c( 800~--------------------------------------~ 700 600 500 400 300 200 100 20 30 40 50 70 80 90 100 % EXCEEDANCE ANNUAL FLOW DURATION BRADLEY RIVER WITH GLACIER WASTING TREND REMOVED ...___ ________ FIGURE 5.3-5 ____. 6 ENGINEERING AND ECONOMIC EVALUATIONS MANUFACTURERS TURBINE DATA Sheet 1 of 3 30 MW UNITS -VERTICAL SHAFT MACHINES ------------------------FRANCIS TURBINES--------------------------------------------------PELTON TURBINES------------------ DATA PRICES: millions (1) Two Turbines Installation Two Inlet Valves Installation Two Bypass Valves Installation Two Governors Installation TOTAL INSTALLED RATINGS: Rated Power, MW Rated Flow, CFS Rated Head, FT Sync. Speed, RPM Specific Speed (Engl.) Runaway Speed, RPM No. of Jets (Pelton) Submergence of Runner ALLIS CHALMERS incl. incl. incl. incl. 0.24 incl. incl. incl. $4.64 30.00 342.00 1112.00 900.00 28.10 at c.l., ft -12.40 DIMENSIONS: (Ft.) Runner Throat Diameter Runner O.D. Runner Height Spiral Case Inlet Dia. Overall Width of 4.17 Spiral Case 11.85 Draft Tube Depth from c.l. 10.20 Total Draft Tube Depth from min. TWL 22.60 Draft Tube Outlet Width 8.32 Head Cover O.D. Distributor Height WEIGHTS: (lbs) Runner Spiral Case Total Turbine Weight Hydraulic Thrust COMMENTS DOMINION ENGINEERING SULZER WORKS, LTD. BROS., INC. $5.05 1.10 1.50 0.20 0.75 0.10 incl. incl. $8.70 34.25 1112.00 900.00 30.00 1360.00 -19.00 3.50 5.20 1.90 3.66 13.90 11.35 30.35 8.90 5,900 21,000 95,000 94,000 $1.67 0.32 0.75 0.075 0.70 0.05 $3.565 30.00 419.00 1112.00 900.00 30.00 1520.00 -46.00 3.10 4.20 1.50 3.30 11.55 9.60 55.60 6.70 5.40 0.62 14,000 42,000 120,000 74,500 (1) FOB jobsite unless otherwise noted *Will not produce rated power at min. head. KVAERNER BRUG A/S TOSHIBA $1.73 1.25 0.89 0.20 0.63 $4.70 30.00 353.00 1112.00 720.00 22.80 1135.00 -22.00 3.12 5. 31 1.80 2.95 12.55 21.40 43.40 7-90 0.55 $2.70 0.76 o.8o 0.25 incl. incl. incl. incl. $4.51 34.00 399.00 1112.00 600.00 20.00 1067.00 -10.50 6.30 1.74 3-71 15.83 10.83 21.33 13.45 8.53 9,330 5,800 13,120 22,000 120,000 40,000 NISSHO IWAI ALLIS (FUJI) CHALMERS $5.25 Price incl. incl. includes incl. Gen. and is incl. FOB Japan. No installa-- tion or freight. 30* 348.00 1112.00 720.00 22.40 1280.00 -15.00 3.50 5.80 2. 30 2.90 14.40 10.34 25.34 8.40 6.36 0.61 5,820 39,000 90,200 incl. incl. $8.64 30.00 360.00 6.00 6.75 SULZER BROS. ,INC. $1.90 0.32 0.75 0.75 0.70 0.05 $4.47 30.00 427.00 1100.00 360.00 660.00 6.00 +12.50 6 .• 55 8.33 4.27 32.27 17.85 5.35 13.41 14,100 64,000 190,000 *Will not produce rated power at min. head. KVAERNER NISSHO IWAI BRUG A/S (FUJI) $2.70 1.35 0.89 incl. 0.63 incl. $5.57 30.00 352.00 1100.00 400.00 705.00 6.00 +7.50 6.09 7.87 4.25 31.25 19.00 11.50 12.50 14,800 33,000 $6.06 Price includes Gen. and is FOB Japan. No installa- tion or freight. 30* 354.00 1100.00 400.00 5.10 730.00 6.00 +8.00 5.97 8.20 4.27 27.80 14.50 6.50 12.00 11,550 34,000 247,700 L------~------------:---------------TABLE 6.2-1 MANUFACTURERS TURBINE DATA Sheet 2 of 3 45 r-1W UNITS -VERTICAL SHAFT MACHINES ----------------------------FRANCIS TURBINES-------------------------------------------------PELTON TURBINES------------------ DOMINION ALLIS ENGINEERING SULZER KVAERNER NISSHO IWAI ALLIS SULZER KVAERNER NISSHO IWAI DATA CHALMERS WORKS, LTD. BROS., INC. BRUG A/S TOSHIBA (FUJI) CHALMERS BROS. ,INC. BRUG A/S (FUJI) PRICES: millions (1) Two Turbines $5.070 $6.30 $1.90 $2.175 $3.90 $6.66 incl. $2.60 $3.383 $7.65 Installation incl. 1.20 0.34 1.347 1.10 Price incl. 0.34 1.444 Price includes Two Inlet Valves incl. 1.90 1.03 1.128 1.20 includes incl. 1.03 1.128 Gen. and is Installation incl. 0.25 0.10 0.34 Gen. and is incl. 0.10 incl. FOB Japan. __ T_w~-~yp_g~~-Yalve::; _Q. 25_!3_ 0.95 0.234 incl. FOB Japan. No installa- Installation incl. 0.12 incl. .No-Ins taiia---fion-or-- Two Governors incl. incl. 0.80 0.715 incl. tion or incl. 0.80 0.715 freight. Installation incl. incl. 0.05 incl. freight. incl. 0.05 incl. TOTAL INSTALLED $5.328 $10.72 $4.22 $5.600 $6.54 $11.61 $4.92 $6.670 RATINGS: Rated Power, MW 46.80 52.50 45.00 45.00 51.00 45* 45.00 45.00 45.00 45* Rated Flow, CFS 533.00 622.00 530.00 597.00 521.00 639.00 530.00 530.00 Rated Head, FT 1112.00 1112.00 1112.00 1112.00 1112.00 1112.00 1100.00 1100.00 1100.00 Sync. Speed, RPM 720.00 720.00 720.00 600.00 514.00 600.00 300.00 300.00 360.00 327.00 Specific Speed (Engl.) 28.00 30.00 30.00 23.30 21.00 22.90 5.10 Runaway Speed, RPM 1100.00 1220.00 950.00 917.00 1060.00 550.00 640.00 600.00 No. of Jets (Pelton) 6.00 6.00 6.00 6.00 Submergence of Runner at c.l., ft -12.40 -19.00 -46.00 -22.00 -13.10 -15.00 +14.30 +9.20 +8.20 DIMENSIONS: (Ft.) Runner Throat Diameter 4.33 3-90 3-83 4.25 8.10 7.84 6.77 7.28 Runner O.D. 5.22 6.40 5.24 6.36 7.40 1.00 10.00 9.00 9.84 Runner Height 2. 30 2.20 2.25 2.10 2.70 Spiral Case Inlet Dia. 4.43 4.53 4.30 3.60 4.46 3.50 5.58 5.10 5.20 Overall Width of Spiral Case 14.82 17.20 14.65 16.97. 18.86 17.55 37-75 33-91 Draft Tube Depth from c.l. 12.80 14.05 12.00 23.03 13.06 12.94 20.83 23.30 16.00 Total Draft Tube Depth from min. TWL 25.20 33.00 58.00 45.03 26.16 28.00 6.56 14.10 7.80 Draft Tube Outlet Width 10.40 11.00 8.40 9.30 16.40 10.30 16.40 14.75 14.70 Head Cover O.D. 6.70 10.10 9.02 Distributor Height 0.78 0.69 0.75 -~IG_H'J.'~: <1!>!3) Runner 10,000 20,000 fl,TBo 9,550 -·rn-,700-Z6,0UO ra;so·o--zl-~ ro·o- Spiral Case 28,000 60,000 21,870 33,000 59,500 41,200 54,500 Total Turbine Weight 155,000 160,000 180,000 175,000 360,000 362,200 Hydraulic Thrust 150,000 117,000 60,000 134,200 COMMENTS *Will not *Will not produce produce (1) FOB jobsite unless otherwise noted rated power rated power at min. head. at min. head. TABLE 6.2-1 MANUFACTURERS TURBINE DATA Sheet 3 of 3 67.5 MW UNITS-VERTICAL SHAFT MACHINES ---------------------------------FRANCIS TURBINES---------------------------------------------PELTON TURBINES------------------ DATA PRICES: millions (1) Two Turbines Installation Two Inlet Valves Installation Two Bypass Valves Installation Two Governors Installation TOTAL INSTALLED RATINGS: ALLIS CHALMERS incl. incl. incl. incl. 0.30 incl. --------- incl. incl. $6.35 Rated Power, MW 67.50 Rated Flow, CFS 770.00 Rated Head, FT 1112.00 Sync. Speed, RPM 600.00 Specific Speed (Engl.) 28.10 Runaway Speed, RPM No. of Jets (Pelton) Submergence of Runner at c.l., ft -12.40 DIMENSIONS: (Ft.) Runner Throat Diameter Runner O.D. 6.26 Runner Height Spiral Case Inlet Dia. 5.32 Overall Width of Spiral Case 17.80 Draft Tube Depth from c.l. 15.35 Total Draft Tube Depth from min. TWL 27.75 Draft Tube Outlet Width 12.50 Head Cover O.D. Distributor Height WEIGHTS: (lbs) --Runnel"' Spiral Case Total Turbine Weight Hydraulic Thrust COMMENTS --- DOMINION ENGINEERING WORKS, LTD. $8.20 1.40 2.50 0.32 1.25 ___ Q_.l5 - incl. incl. $13.82 77.00 lll2.00 600.00 30.00 910.00 -19.00 5.25 7.80 2.80 5.49 20.75 17 .oo 36.00 13.36 - -i6,i{j(J- 40,000 235,000 220,000 (1) FOB jobsite unless otherwise noted SULZER BROS., INC. $2.20 0.39 1. 34 0.11 KVAERNER BRUG A/S $2.89 1.44 1.40 incl. 0.28 TOSHIBA $5.50 1.40 1.63 0.46 incl. NISSHO IWAI (FUJI) $8.47 Price includes Gen. and is FOB Japan. ALLIS CHALMERS incl. incl. incl. incl. SULZER BROS. ,INC. $3.20 0.39 1. 34 0.11 -___ .Jncl_. ________ incl~--_ .N~_i_l'l_st-.alla .... ______ --_ ----------- 0.90 0.05 $4.99 0.78 incl. tion or incl. incl. freight. $6.79 $8.99 67.50 941.00 1112.00 600.00 30.00 1010.00 -46.00 4.70 6.30 2.80 5.00 17.70 14.50 60.50 10.20 8.00 0.94 67.50 795.00 lll2.00 514.30 24.50 820.00 -22.00 4.69 7.45 2.91 4.40 17.96 26.00 48.00 10.90 0.89 76.50 890.00 1112.00 450.00 22.50 809.00 -17.10 8.50 2.54 5.40 22.05 15.52 32.60 19.36 11.65 --3CJ-,CH)0 75,000 200,000 169,000 --:t3,J.20-- - - -~5 ,-ono- 34,020 49,000 80,000 *Will not produce rated power at min. head. 250,000 67.5* 784.00 lll2.00 514.00 24.00 910.00 -19.00 5.10 8.20 3.00 4.24 21.10 15.85 34.85 13.00 10.84 0.90 --ra,-goo-- 85,500 258,000 194,000 incl. incl. $16.47 0.90 0.05 $5.99 67.50 240.00 6.00 10.10 67.50 962.00 1100.00 257.10 5.00 470.00 6.00. +17. 30 9.14 ll.70 6.56 45.71 25.30 20.12 -4-o,auo 180,000 500,000 *Will not produce rated power at min. head. KVAERNER BRUG A/S $4.21 1.54 1.40 incl. NISSHO IWAI (FUJI) $10.50 Price includes Gen. and is FOB Japan. No installa- --___ tion-or- 0.78 incl. $7-93 67.50 795.00 llOO.OO 277.00 5-37 490.00 6.00 +11.10 8.80 11.52 6.25 46.45 28.50 18.70 freight. 67.5* 797.00 1100.00 257.00 4.90 470.00 6.00 +10.00 9-35 12.80 6.40 43.85 19.00 9.00 18.00 -- ----3-4,-5-00 - - --lf?' 15-0 - - - ---- - - - - - -- - - -- - 66,200 82,600 596,000 L..-----~-----------~-------TABLE 6.2-1 MANUFACTURERS GENERATOR DATA Sheet 1 of 6 ---------ALTERNATIVE 1. 33334 KVA 720 RPM VERTICAL FRANCIS----------- DATA GE Co. TOSHIBA SIEMENS-ALLIS HITACHI AVERAGE Price - 2 units $3.60 $3.10 $2.26 $5.00 $3.50 (millions of $) · -±nsta·l-la-t-ion .. ---l-.-3-3-·------. -0-.-1-7--·-.. ·o-.-79-·-N;A-· -------- Total Price 4.93 3-87 3.05 5.00 4.20 FOB Point Jobsite Japan Jobsite Jobsite Jobsite Efficiency 100% 97.7 97.6 97.6 97.2 97.5 at Percent 75% 96.8 Load 50% 95.7 25% 92.2 Overall Height/in 252 240 184 295 243 Overall Diameter 180 232 260 145 204 (in) Total Weight/lbs 210,000 310 '900 320,000 265,000 276,000 Size of Largest 144xl44xl32 9lxl73x90 No data 150xl50xl00 Piece/in. (stator sect) (stator) Weight Largest 80,000 52,900 160,000 90,000 95,725 Piece/lbs (1) (stator sect) (stator sect) (rotor/shaft) Location of Above Above Above Above Above thrust bearing, above or below rotor Notes: (1) In most cases, the weight of the largest piece is a shipping weight. For maximum crane lift, use 40% of total weight for vertical units. (Rotor weight) For maximum crane lift, use weight of largest piece for horizontal units. -----ALTERNATIVE 2. 50000 KVA 600 RPM VERTICAL FRANCIS--- GE Co. TOSHIBA SIEMENS-ALLIS HITACHI AVERAGE $5.30 $4.10 $3.22 $5.80 $4.60 . --r.;-9·6-· --r.o·o------ - - -r:-rT ---------------------- -N/A 7.26 5.10 4. 35 5.80 5.63 Jobsite Japan Jobsite Jobsite Jobsite 97-7 97.8 97.6 97.5 97.65 97.1 96.2 93.4 290 256 198 315 265 240 256 285 180 240 380,000 443,100 400,000 370,000 400,000 204xl20xl00 106xl97xl02 No data 175x87xl05 (stator sect) (stator) 66,000 75,000 200,000 60,000 70,000 (stator sect) (stator sect) (rotor/shaft) (not incl. S.A.) Above Above Above Above Above ~----------~----------------~----------------~~----TABLE 6_2-2 MANUFACTURERS GENERATOR DATA Sheet 2 of 6 -----ALTERNATIVE 3. 75000 KVA 514.3 RPM VERTICAL FRANCIS------------- DATA GE Co. TOSHIBA SIEMENS-ALL IS HITACHI AVERAGE Price - 2 units $6.00 $5.50 $4.26 $6.90 $5.66 (millions of $) Installation 2.22 1.40 1.49 N/A Total-El"-ic e - - - ... -... 8.22------.. -6.-90 - -.. - -5. 7-5---6.-90 - - -- -----6.-95-- FOB Point Jobsite Japan Jobsite Jobsite Efficiency 100% 98.0 97.9 97.6 97.6 at Percent 75% 97.2 Load 50% 96.4 25% 93.7 Overall Height/in 280 244 222 335 Overall Length/in Overall Diameter 260 287 306 205 (in) Total Weight/lbs 454,000 613,000 640,000 595,000 Size of Largest 204xl05xl30 106xl97xl02 No data 205xl0 3xl20 Piece/in. (stator sect) (stator) (stator) Weight Largest 88,000 75,000 320,000 100,000 Piece/lbs (1) (stator sect) (stator sect) (rotor/shaft) (stator) Location of Above Above Above Above thrust bearing, above or below rotor Notes: (1) In most cases, the weight of the largest piece is a shipping weight. For maximum crane lift, use 40% of total weight for vertical units. (Rotor weight) For maximum crane lift, use weight of largest piece for horizontal units • Jobsite 97.77 270 245 575,000 90,000 Above --ALTERNATIVE 4. 33334 KVA 720 RPM HORIZONTAL GE Co. TOSHIBA SIEMENS-ALLIS HITACHI $3.40 $2.90 $2.20 $4.50 1.23 0.70 0.77 N/A .. -4.6-J--- ----~·-60 2.-9-7-. --4.~0-- Jobsite Japan Jobsite Jobsite 97.7 97.7 97.6 97.3 252 232 226 295 180 15lt 146 155 210,000 154 '000 No data 245,000 144xl44xl32 53xl8lxl54 No data 195xl00xl55 (stator sect) 80,000 46,300 160,000 65,000 (stator sect) (stator sect) (rotor/shaft) (stator) FRANCIS-- AVERAGE $3.25 .... -3--9-3 Jobsite 97.6 96.9 95.9 92.5 251 158 203,000 88,000 .__ _____________ ......__ __________ TABLE 6.2-2----- MANUFACTURERS GENERATOR DATA Sheet 3 of 6 --------ALTERNATIVE 5. 50000 KVA 600 RPM HORIZONTAL FRANCIS---------- DATA GE Co. TOSHIBA SIEMENS-ALLIS HITACHI Price - 2 units $5.00 $3.80 $3.00 $5.20 (millions of $) Installation 1.85 0.95 .1.05 N/A ----------6.85 4.75 4.05 5.20 Total Price FOB Point Jobsite Japan Jobsite Jobsite Efficiency 100% 97.7 97.9 97.6 97.6 at Percent 75% 97-3 Load 50% 96.4 25% 93.7 Overall Height/in Overall Length/in 290 268 232 310 Overall Diameter 240 173 166 180 (in) Total Weight/lbs 380,000 181,000 No data 345,000 Size of Largest 204xl20xl00 63x20lxl73 No data 230xl05xl80 Piece/in. (stator sect) (stator) Weight Largest 66,000 53,900 200,000 100,000 Piece/lbs (l) (stator sect) (stator sect) (rotor/shaft) (stator) Location of thrust bearing, above or below rotor Notes: (l) In most cases, the weight of the largest piece is a shipping weight. For maximum crane lift, use 40% of total weight for vertical units. (Rotor weight) For maximum crane lift, use weight of largest piece for horizontal units. AVERAGE $4.25 5.21 Jobsite 97-7 275 190 302,000 74,000 (stator) --ALTERNATIVE 6. 75000 KVA 514.3 RPM HORIZONTAL GE Co. TOSHIBA SIEMENS-ALLIS HITACHI $5.70 $5.20 $4.00 $6.20 2.11 1.30 1.40 N/A 7.81 6.50 5.40 6.20 Jobsite Japan Jobsite Jobsite 98.0 98.0 97.6 97-7 280 311 250 325 300 197 186 215 454,000 205,000 No data 550,000 210xl05xl30 7lx228xl97 No data 230xl25x215 (stator sect) (stator) 88,000 57,300 320,000 165,000 (stator sect) (stator sect) (rotor I shaft) (stator) FRANCIS-- AVERAGE $5.28 6.50 Jobsite 97.82 97.4 96.6 94.0 293 302,000 100,000 (stator) L..--------------------'----------...----TABLE 6.2-2 MANUFACTURERS GENERATOR DATA Sheet 4 of 6 ---------ALTERNATIVE 7. 33334 KVA 327.3 RPM VERTICAL PELTON---------- DATA GE Co. TOSHIBA SIEMENS-ALLIS HITACHI Price - 2 units $4.20 $3.50 $2.75 $5.50 (millions of $) Installation 1.55 0.85 0.96 N/A Total Price 5.75 4.35 3-71 5.50 FOB Point Jobsite Japan Jobsite Jobsite Efficiency 100% 97.5 97.5 97.5 97.3 at Percent 75% 96.8 Load 50% 95.8 25% 92.7 Overall Height/in 210 213 212 270 Overall Diameter 280 283 300 215 (in) Total Weight/lbs 300,000 381,400 400,000 430,000 Size of Largest 250xl25x75 7lxl6lx83 No data No data Piece/in. (stator sect) Weight Largest 50,000 33,100 200,000 No data Piece/lbs (1) (stator sect) (stator sect) (rotor/shaft) Location of Above Below Above Above thrust bearing, above or below rotor Notes: (1) In most cases, the weight of the largest piece is a shipping weight. For maximum crane lift, use 40% of total weight for vertical units. (Rotor weight) For maximum crane lift, use weight of largest piece for horizontal units. AVERAGE $4.00 4.83 Jobsite 97-5 226 270 378,000 42,000 Above ---ALTERNATIVE 8. 50000 KVA 240 RPM VERTICAL GE Co. TOSHIBA SIEMENS-ALLIS HITACHI $5.50 $5.00 $3.45 $6.70 2.04 1.20 1.20 N/A 7.54 6.20 4.65 6.70 Jobsite Japan Jobsite Jobsite 97.6 97-7 97.4 97.6 220 228 224 285 330 339 360 295 420,000 566,600 560,000 700,000 300xl50x70 79x20lx94 No data No data (stator sect) 80,000 48,500 280,000 No data (stator sect) (stator sect) (rotor/shaft) Above Below Above Above PELTON--- AVERAGE $5.18 6.27 Jobsite 97.6 97.3 96.4 93.7 240 331 561,000 Above &...-----------------------------TABLE 6.2-2 ___. MANUFACTURERS GENERATOR DATA Sheet 5 of 6 --------ALTERNATIVE g. 75000 KVA 276.9 RPM VERTICAL PELTON----------- DATA GE Co. TOSHIBA SIEMENS-ALLIS HITACHI Price - 2 units $6.40 $6.40 $4.70 $7.70 (millions of $) Installation 2. 37 1.60 1.65 N/A Total Price 8.77 8.00 6.35 7-70 FOB Point Jobsite Japan Jobsite Jobsite Efficiency 100% 97.9 97-9 97.6 97.8 at Percent 75% 97.5 Load 50% 96.7 25% 94.2 Overall Height/in 250 272 236 295 Overall Length/in Overall Diameter 300 339 360 255 (in) Total Weight/lbs 570,000 758,400 600,000 900,000 Size of Largest 290xl45xl00 95xl97x95 No data No data Piece/in. (stator sect) Weight Largest 90,000 54,000 300,000 No data Piece/lbs {1) (stator sect) (stator sect) (rotor/shaft) Location of Above Below Above Above thrust bearing, above or below rotor Notes: (1) In most cases, the weight of the largest piece is a shipping weight. For maximum crane lift, use 40% of total weight for vertical units. (Rotor weight) For maximum crane lift, use weight of largest piece for horizontal units. AVERAGE $6.36 7. 71 Jobsite 97.8 263 313 707,000 Above ---ALTERNATIVE 10. 33334 KVA 327.3 RPM HORIZONTAL GE Co. TOSHIBA SIEMENS-ALLIS HITACHI $4.00 $3.20 $2.60 $4.90 1.48 0.80 0.91 N/A 5.48 4.00 3.51 4.90 Jobsite Japan Jobsite Jobsite 97.5 97.6 97.6 97.4 210 295 250 315 280 197 210 235 300,000 187,000 400,000 375,000 250xl25x75 45x228xl97 No data 280x80x235 (stator sect) (stator) 50,000 55,100 200,000 120,000 (stator sect){stator sect) (rotor/shaft) (stator) PELTON-- AVERAGE $3.68 4.47 Jobsite 97.5 97.0 96.0 93.0 268 231 317,000 100,000 L--------------~.;,....__ _____________ TABLE 6.2-2 ___, MANUFACTURER'S GENERATOR DATA Sheet 6 of 6 -------ALTERNATIVE 11. 50000 KVA 276.9 RPM HORIZONTAL PELTON--------- DATA GE Co. TOSHIBA SIEMENS-ALLIS HITACHI Price - 2 units $5.10 $4.70 $3.40 $5.90 (millions of $) Installation 1.90 1.20 1.19 N/A Total Price 7.00 5.90 4.59 5.90 FOB Point Jobsite Japan Jobsite Jobsite Efficiency 100% 97.65 97.8 97.6 97.6 at Percent 75% 97.3 Load 50% 96.6 25% 94.1 Overall Height/in Overall Length/in 240 354 250 335 Overall Diameter 310 220 272 265 (in) Total Weight/lbs 390,000 212,000 540,000 575,0b0 Size of Largest 270xl35x80 59x252x220 No data 310xl00x265 Piece/in. Weight Largest 75,000 61,700 270,000 155,000 Piece/lbs (1) (stator sect) (stator sect) (rotor/shaft) (stator) Location of thrust bearing, above or below rotor Notes: (1) In most cases, the weight of the largest piece is a shipping weight. For maximum crane lift, use 40% of total weight for vertical units. (Rotor weight) For maximum crane lift, use weight of largest piece for horizontal units. AVERAGE $4.78 5.85 Jobsite 97.7 295 267 430,000 ....__ ____________ TARI F A?-? PRELIMINARY ANNUAL ENERGY -GWH 2 UNITS EQUAL SIZE 3 UNITS EQUAL SIZE OPERATING GENERATING HEADWATER NCMINAL PLANT RATING AND UNIT TYPE NCMINAL PLANT RATING AND UNIT TYPE FLOW REGIME POOL ELEVATION FRANCIS PELTON FRANCIS 60 MW 60 MW Mid.Fork Fish Div. Max. HW Min. HW FIRM SEC AVG.AN. FIRM SEC AVG.AN FIRM SEC AVG.AN With Without 1170 1081 304.6 19.3 323.9 329.9 19.2 349.1 Without With 1170 1081 280.9 25.2 306.0 296.7 21.2 317.8 With With 1170 1081 280.9 35.9 316.7 304.1 26.5 330.6 80 MW 90 MW With Without 1170 1081 Without \-lith 11 7n 1081 ..A...A.I""' With With 1170 1081 312.3 31.3 343.7 285.6 45.5 331.1 90 MW 90 MW 120 MW With Without 1170 1081 333.9 28.2 362.1 332.0 29.7 361.6 Without With 1170 1081 291.8 30.7 322.5 298.2 31.8 329.9 With With 1170 1081 304.5 35.5 340.0 308.2 37.3 345.5 313.4 44.13 357.4 135 MW 135 MW 135 MW With Without 1170 1081 282.5 39.0 321.5 333.2 37.2 370.4 334.6 36.4 371.0 Without With 11'(0 1081 239.2 41.9 281.1 299-3 39.1 338.3 292.5 38.6 331.1 With With 1170 1081 255.0 48.1 303.1 309.2 47.5 356.6 306.9 46.2 353.1 BASIS OF RESULTS: 1. Bradley River flows from Corps of Engineers' Design Memo Number 2, Tables 7 -1. 2. Middle Fork flows, unregulated basin flows and fish diversion flows (30 cfs min./150 cfs max.) based on preliminary estimates • .....__---------------------------TABLE 6.2-3 MAX HW 1170 1170 1180 1180 1190 1190 RESERVOIR ELEVATIONS SENSITIVITY ANALYSES 90 MW PELTON -TWO 45 ·Mw UNITS MIN HW 1081 1060 1081 1060 1081 1060 PREL~INARY GENERATING FLOWS WITH MIDDLE FORK (30 CFS MINi150 CFS MAX) AVERAGE ANNUAL ENERGY --GWHRS FIRM SECONDARY AVG. ANNUAL 308.2 37.3 345.5 313.5 33.1 346.6 318.4 32.6 350.9 323.6 27.8 351.4 328.3 27.3 355.5 333.8 18.6 352.4 '-----------------------T A r:n r= a 1'\_ .A __ MIDDLE FORK INPUT •1170, 1081 MAX, MIN HWEL • FRANCIS, PEL TON ALL CAPACITIES __.. • CAPITAL COST .-----... .,.. • ENERGY BENEFIT TUNNEL BORING ECONOMIC POWER MACHINE TUNNEL DIAMETER INPUT INPUT • GEOTECHNICAL • DIAMETERS DATA • 60, 90, 135 MW •COST PLANT CAPACITY • POWER TUNNEL r-+ • ENERGY LOSS COST ARRANGEMENT • CAPITAL COST ALTERNATIVES METHODOLOGY • UTILIZE TBM • MINIMIZE TOTAL • CONVENTIONAL METHODS COST DECISION DECISION • UTILIZE TBM • 60 MW-10FT • 90 MW-11FT •135MW-12 FT NOTES: 1. ECONOMIC EVALUATIONS BASED ON MAXIMUM VALUE OF BENEFITS LESS COSTS 2. FLOW REGIMES 01 =BRADLEY RIVER, WITH MIDDLE FORK, WITH FISH DIVERSIONS 02 =BRADLEY RIVER, WITH MIDDLE FORK, WITHOUT FISH DIVERSIONS 03 =BRADLEY RIVER, WITHOUT MIDDLE FORK, WITH FISH DIVERSIONS r-+ 01,02 FLOWS ALTERNATIVES • CONSTRUCT • ABANDON DECISION • CONSTRUCT TURBINE TYPE INPUT • 1170, 1081 MAX, MIN HWEL • FRANCIS, PELTON ALL CAPACITIES • 01, 02, 03 FLOWS • ENERGY BENEFITS • CAPITAL COSTS ALTERNATIVES • FRANCIS • PELTON DECISION • PELTON DAM TYPE INPUT • CAPITAL COSTS DAMS AND ASSOCIATED STRUCTURES ALTERNATIVES • CONCRETE GRAVITY • ROCKFILL DECISION • ROCKFILL r-. ,, PL~NT CAPACITY I INPUT • 1 1'71li, 1081 MAX, MIN HWEL • Hp'W REGIME 01 • PELTON TURBINES AL!L CAPACITIES • TdTAL ESTIMATED~ CAPIITAL COST • EN:ERGY BENEFITS • ECpNOMIC ~~~~~~~~~O~ODE L ALT~RlNATIVES • 6oMw • 90MW • 13SMW DECISION • 90 jvlw ~,J RESERVOIR OPERATING LEVELS INPUT • FLOW REGIME 01 • 90 MW PELTON • ROCKFILL DAM • TOTAL CAPITAL COST • ENERGY BENEFITS ALTERNATIVES • MAX HWEL 1170, 1180, 1190 • MIN HWEL 1081, 1080, 1060 DECISION • MAX HWEL 1180 • MIN HWEL 1080 RECOMMENDED DEVELOPMENT PLAN • 11' POWER TUNNEL ARRANGEMENT SUITABLE FOR TBM EXCAVATION • 90 MW PEL TON PLANT • MIDDLE FORK DIVERSION FACILITY • ROCKFILL DAM • MAX HWEL 1180 • MIN HWEL 1080 i • ASSESSMENT OF PRINCIPAL FEATURE~· -BRADLEY LAKE PROJECT .____ __________ .....;... ____ FIGURE 6.1-1- (I) u. (.) 150 130 110 s: 90 0 ..J u. 70 50 30 1- t- t- - t- ~ I I JAN FEB I I I I I I I I I MAR APR MAY JUN Jl:JL AUG SEP OCT NOV DEC TIME-MONTHS PRELIMINARY INSTREAM FLOWS ·---FIGURE 6.1-2 6.0 5.9 5.8 50 MIL ENERGY CAPITAL COST INCREASED 20% 5.7 en z 0 ...I 5.4 ..0 ...I 0~ :iE ~ 0 . ~ 1-en ~ 0 5.3 ~ (J ...I <( 70 MIL ENERGY ::I z 2 <( 5.2 ...I <( 1- 0 1- 5.1 5.0 50 MIL ENERGY 4.9 4.8 9 10 11 12 STEEL LINER DIAMETER-FT. NOTE: COST OF CAPITAL BASED ON 3.5% INTEREST FOR 50 YEARS ECONOMIC DIAMETER ANALYSIS POWER CONDUIT -90 MW PLANT ~--------------------------------CI~I 10~ 1- I a '>--t_j \_EXCAVATE TO EL.1070'\ BRADLEY LAKE MAXIMUM OPERATING W.S. EL.118d MINIMUM OPERATING W.S. EL.1080' -- T.O.DAM"\ DRAINAGE GALLERY EL.1085' 'DAM i rEL.1165' 7.1 J10 EL.1065' EL.1070' 5' VARIES MAXIMUM GRAVITY SECTION NOTE: NORMAL W.S. DRAINAGE GALLERY EL.1085' ELEVATIONS SHOWN ARE ON PROJECT DATUM. , MEAN SEA LEVEL DATU~~= PROJECT DATUM PLUS 4.02 FT. ,.,. 50. 000' ,,_,, GRAPHIC SCALE 1"•~'-0~ 0 20' 40' pr.·.·--I SCALE IN fEET EL 1070 VARIES MAXIMUM SPILLWAY SECTION 0 20' 40' M" ..... 1 SCAlE IN FEET AlTERNATIVE CONCRETE GRAVITY DAM CONCEPT 400 ~------------------------------------------------------------~ D---a PELTON e e FRANCIS 380 360 .; 340 ... :X: 3: AVERAGE ANNUAL e, > e, a: 320 w z w ...1 <( ::;, z 2 <( 300 I FIRM 280 260 240 ~--~------~------~-------...1~------~------~------~------~ 60 so· 100 120 140 NOMINAL PLANT RATING-MW NOTE: CURVES BASED ON EQUAL SIZE UNITS MAXIMUM HW EL 1170. MINIMUM HW EL 1081. BRADLEY RIVER FLOWS FROM CORPS OF ENGINEERS DESIGN MEMORANDUM NO. 2 TABLE 7-1 WITH MIDDLE FORK FLOWS WITH FISH DIVERSION FLOWS 160 ENERGY EVALUATJONS FRANCIS AND PELTON TURBINES 180 ---------FIGURE 6.2-3---....~ 160 r---------------------------------------------------~ z 0 140 :J ...1 ~ ~ ~ en 120 0 (.) ...1 ·c:t 1-a:: ;3 100 en en w ...1 en !- u. ~ 80 w ,a:l Q w 1-<t ~ ~ 60 en w o---o PELTON ee---ee FRANCIS -o-----------o 2UNITS cY"' 40 ~--~------._ ______ ._ ______ ~------~------~------~ 60 80 100 120 140 NOMINAL PLANT CAPACITY · MW NOTE: NET BENEFITS DO NOT INCLUDE COST OF 230 kV ANCHORAGE INTERTIE TRANSMISSION LINE REQUIRED FOR PLANT CAPACITIES ABOVE 90 MW. COMPARATIVE EVALUATIONS FRANCIS AND PELTON TURBINES 160 180 "----------FIGURE 6.2-4 ! l UNIT I 33'-o" 34'-o· EI::RUNNER EL--17\ TYPICAL CROSS SECTION • , .. 20' , I SCALE IN FE£T [T.O.RAIL EL.40.5' rEL.20' 10'-ci' (MIN.) r UtiiT 2 LONGITUDINAL SECTION . , .. e SCALE IN FEET NOTE: ELEVATIONS SHOWn \i<E ON PROJECT DATUM. ... I MEAN SEA LEVEL DATUM~PROJECT DATUM PLUS 4.02 FT. i I ( UNIT1 I 48'-o" BRIDGE CRANE ALTERNATIVE [T.O.RAIL EL40.5' rELc10' 90 MW FRANCIS UNIT POWERHOUSE SHT. 1 FIGURE 6.2-5 UNIT 2 UNIT 1 =o -~ UNITS I PLAN-FLOOR EL. 20' 0 , .. ,.. ....... I SCALE IN FEET UNIT 2 q UNIT 1 2<0-o" 37'-o' 35'-o• 331-01 ' 37'0" 27'-0' ! ! PLAN-FLOOR EL-10' ... SCALE IN FEET =o -~ UNITS ·-. .i ~:.i. .. : GENERATOR BUS VAULT UNIT 2 25'-o" ,_ PLAN-FLOOR EL. 2' . , .. ,.. N I SCALE IN fEET EQUIPMENT DATA 1 GENERATOR 14 SPHERICAL VALVE CONTROL 2 CONTROL PANELS 15 SPHERICAL VALVE ACCUMULATORS 3 GENERATOR BREAKER 16 UNIT SERVICE WATER PUMPS 4 GENERAlOR POTENTIAL 17 FIRE PUMPS TRANSFORMER 18 AIR COMPRESSORS 5 NEUTRAL TRANSFORMER 19 AIR DRYER 6 DIESEL GENERAlOR 20 AIR TANK 7 STATIC EXCITATION 21 WATER PURiFICATION EQUIPMENT 8 GOVERNOR ACTUATORS 22 WATER TREATMENT 9 GOVERNOR OIL ACCUMULATORS 23 DOMESTIC PUMPS 10 GREASING UNITS 24 JOCKEY PUMP 11 MOTOR CONTROL CENTERS 25 HOT WATER HEATER 12 480V LOAD CENTER 26 OIL SER\RATOR & 480 V SWITCHGEAR 27 SEWAGE TREATMENT MODULE 13 BATTERY 28 AIR RECEIVER 29 UNIT/STATION SUMP 30 DIRTY WATER SUMP UNIT1 NOTE: BATIERY ROOM ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM= PROJECT DATUM PLUS 4 •. 02 FT. ALTERNATIVE 90 MW FRANCIS UNIT POWERHOUSE SHT. 2 FIGI JRI= A ~-R 800~------------------------------------------------~ 700 600 300 200 • I II .. II ., It II I I I I I I I I I I I AVERAGE 484 . -------\- ---~----------------\- ' AVERAGE 476_j ---MEASURED WITH BASIN ADJUSTMENTS ----CORRECTED FOR ESTIMATED GLACIER INFLUENCE 100~~--------~--------._--------~------_.--------~ 1960 1965 1970 1975 1980 WATER YEAR (OCT-SEPT) STREAMFLOWS -BRADLEY RIVER AT BRADLEY LAKE ------------FIGURE 6.3-1 Cl) u. 0 ~ ..J u. 150 130 110 90 70 50 30 1- 1- 1- 1- 1- 1- 1- I I JAN FEB I I I I J I I I I MAR APR MAY JUN JUl. AUG SEP OCT NOV DEC TIME -MON"f:I-IS RECOMMENDED INSTRIEAM FLOWS '---------------'-·----FIGURE 6.3-2 7 DETAILED PROJECT DESCRIPTION 7. DETAILED PROJECT DESCRIPTION 7.1 ACCESS FACILITIES 7 .1.1 General The permanent access facilities for the recommended plan, shown on Plates 4, 5, and 6, include the access channel and barge basin, airstrip, and project roads including: o Airstrip to powerhouse o Powerhouse to lower camp (via barge basin and staging area) 0 0 Lower camp to upper camp areas Upper camp to dam (via intake gate shaft, construction diversion tunnel) spillway, and A temporary road will be constructed between the lower camp and the Martin River material borrow site. This temporary road will be used during project construction but will be later removed and the surrounding terrain rehabilitated. Parking, lay down and storage areas will be used for helicopter access. Access to the Middle Fork Diversion dam will be by helicopter only. Under the recommended plan it was determined that satisfactory operation of the turbine units would be achieved without the need for a surge shaft. Therefore, the access road needed for the development of the surge shaft has been eliminated. The feasibility level engineering and design studies and the costs developed for the permanent access facilities were prepared by R&M and are given in greater detail in Appendix B of this report. 7 .1. 2 Barge Basin and Dock Movements of heavy, bulky equipment, construction material and parts to the Bradley Lake Project site can be accomplished economically and with a minimum of social and environmental impacts by waterborne transportation. 7-1 Barge transport allows material and equipment to be prefabricated, largely ~reassembled or modularized at the manufacturer's or fabricator's shop which accelerates field installation. To accommodate the use of sea going barges to support the project construction a small harboring facility or barge basin is required at the project site. Homer, strategically located at the mouth of Kachemak Bay is approximately 27 miles from the project site and would serve to refuel, and provide shelter and services to sea going barges and tugs enroute to and from the project site. Kachemak Bay is characterized from Homer by "deep water" for 15 1/2 miles, shallow conditions for 3 miles, and tidal mud flats for the final 1 1/2 miles to the project site. To accommodate barge traffic, improvements in the 1 1/2 miles approaching the project are required. These improvements include dredging to a depth sufficient to allow sea-going barge and tug traffic; channel markings; barge docking and off loading facilities; and a materials lay down area. In addition, the inclusion of small boat facilities within the barge basin are desirable for construction, and maintenance and operations personnel use. In Kachemak Bay, prevailing winds are from the north during winter and southwest during summer. Summertime windspeeds from the southwest were found to be 35 to 65 percent higher at Sheep Point than at Homer due to funneling effects of the terrain surrounding Kachemak Bay. Wintertime windspeeds were considered equivalent at Sheep Point and Homer since the wind direction does not promote a funneling effect. Table 7. 1-1, Design Wind Speeds at Sheep Point, presents 1 and 12-hour duration winds for exceedance intervals of 2, 5, and 50 years. The summer southwest winds are relatively strong and have a duration which can affect off loading operations. SWEC concurs with the COE that a barge basin sheltered from southwesterly winds is required. Waves associated with the predominant winds were estimated and are presented in Table 7.1-2. Design wave heights are shown at frequency intervals of 2, 5, and 50 years for Sheep Point and Chugachik Island. Tidal exceedance curves were generated by the COE based on 1982 predictions of the Seldovia Station. These curves were together with the wave estimates. Wave estimates by the COE studied may be conservative with regard to the actual frequency of occurrence due to differences between assumed and actual tidal elevations caused by ?-2 continuous tidal fluctuation. Additional study is required to confirm this observation. Observations of Landsat photography and conversations with tug captains familiar with Kachemak Bay conditions led the COE to the conclusion that floating and shore-fast ice should not impact winter shipping movements to the project site. Bottom-fast ice may be produced in the shallow channel which would connect the bay and the barge basin. The bottom-fast ice may be produced by increased formation of frazil ice and adherence in the channel resulting from greater fresh water flows into the Bay from power generation, or the growth of surface ice lenses between high tide periods during extreme cold weather. The operational considerations for the barge basin-dock facilities involve two aspects; barge and tug sizes, and material and equipment movements across the dock. A design barge of size 250 ft. beam by 10 ft. draft, and design tug of size 90 ft. length by 10 ft. draft, were selected based on standard Alaska quantities long by 76 by 30 ft. practice. and ft. beam The handling of material and equipment during barge unloading and loading operations involves roll-off, pass-pass, and crane lift operations. Roll-off operations involve movement of wheeled or tracked vehicles from the barge via a reciprocating off-loading ramp to an earthen ramp rising to the staging area. Pass-Pass operations include barge off-loading via two fork lift trucks, one working on the barge deck passing the load to the other on the dock. The dock fork lift truck would transport the load to the staging area. Crane-lift operations would supplement and support roll-off or pass-pass unloading operations. Channel excavation on the tidal mud flats is probably not feasible in-the-dry due to the soft silty clay, sandy silt and clayey silt deposits which predominate. Excavatio~ by either barge mounted clam-shell or hydraulic suction dredging during tidal periods when sufficient water is available to float the dredge is anticipated. Sedimentation in the access channel and barge basin was studied, but insufficient data exists to make an accurate quantitative determination of the sedimentation rate. A quantitative refinement of the rate of sedimentation in the access channel and barge basin is required which 7-3 should include water sampling and tests at the various tide stages, developing a sedimentation model for predicting sedimentation rates and maintenance requirements, a study of the potential for channel side slope erosion, and the effect of the tidal currents as a source of bed load sediments. The COE published "Bradley Lake Hydroelectric Project Final Environmental Impact Statement 11 , August 1982, which identified that marine mammal, and waterfowl are the most affected life forms by the construction of the access channel and barge basin. The FEIS indicates that any dredge disposal areas on the tidal flats are to be redeveloped into waterfowl habitat at an appropriate time during construction and that such a measure would enhance the nesting habitat of the tidal flats which is currently non-productive due to periodic tidal submergence. During the first year of construction, to accommodate migrating shorebirds, all dredging, dock, and road construction on the tidal flats would cease from May 1 through 15, in accordance with U.S. Fish and Wildlife service recommendations. The recommended dredge spoil disposal area. is located between the powerhouse access road northeast of Sheep Point and the shoreline. The disposal area results in the-loss of approximately 40 acres of sedgegrass vegetation. The spoil will be contoured and seeded to enhance waterfowl nesting habitat as discussed in the FEIS. The details of the disposal area have not been developed. Agency consultation and further study of the dredge spoil disposal area will be conducted during the preparation of the FERC License Application. The access channel from Kachemak Bay to the barge basin has a 200 ft. bottom width. This selection is based on a 1/2 knot tidal current. A turning basin width of 350 ft. was chosen to accommodate the length of the longest barge (up to 343 ft.) using the project facility. To accommodate 10 ft. draft barge movements on 99 percent of all high tides, , or 49 percent of all hourly tidal stages, dredging would be to bottom elevation - 14. Due to the depth and extent of the "shallows 11 at the head of the Bay near the Project site, deepening be~ond elevation -14 would require impractically large dredging quantities to improve the functional value of the barge facility. 7-4 In order to provide crane hook coverages to most of the design barge deck surface area, dock dimensions of 200 ft. length by 50 ft. width are provided. The dock is of timber pile supported deck construction, Plate 6. This type of dock has several advantages including: o Short construction time o Constructed of readily available material o Allows phased construction o Environmental impacts are limited A reciprocating barge off-loading ramp is provided to allow roll-off barge unloading through the full tide cycle. The ramp is 68 ft long and 20 ft wide and is a single span bridge resting on one end upon the barge deck and pivoting on the shore end on a pile supported concrete abutment. Above the pile supported abutment is a concrete log surface ramp having a maximum 15 percent grade up to the staging area at elevation 18. The small .J:>oat launch ramp is built of granular material placed in the barge basin: and surfaced with concrete logs. The ramR has a maximum 15 percent grade up to the staging area at elevation 18. The staging or laydown area, and dock access roads are constructed of well compacted graded granular borrow material placed upon the tidal mud flat north of Sheep Point. These soil pads are to be built north of the slough oriented east to west at Sheep Point. A 100 ft long, single lane bridge crosses over the slough to connect the barge basin facilities and the lower camp to powerhouse access road. 7.1.3 Access Roads The access roads required to support construction of the major project structures and later operations and maintenance are as follows: o Airport to Powerhouse o Powerhouse to Lower Camp (via barge basin and staging area) o Lower Camp to Upper Camp o Upper Camp to dam (via intake gate shaft, spillway and construction diversion tunnel) 7-5 The general layout plan which shows the interrelationships of the access roads and project structures is shown on Plate 4. Typical road cross-sections are included in Appendix B. The recommended road types should allow required access and permit economical construction of the ~pro-j-e-ct~stru-ctures~. ~A~two----l~an-e~ro-a-d~tn-a-h~i~gh_t_r_a_f~f-i-c-are-a-ancl.~s-ingle-1-ane road in a low traffic area is warranted. The road to the surge shaft will not be required under the preferred plan. Critical data considered in the conceptual design of the recommended road system were as follows: Two Lane Single Lane 0 Design Speed, mph 20 20 0 Lane Width, ft 12 12 0 Shoulders, ft 2 2 0 Horizontal Curves (Minimum Radius), ft. 100 100 0 Sight Distances, ft. 150 300 o Vertical Curves To be calculated in accordance with State of Alaska DOTPF Highway Preconstruction Manual Procedure 11-10-5. Value dependent on design speed and grade difference. Note: "K" value for a single lane two direction road is four times that for a two-lane road. o Grades Desirable 10% Maximum 14% o Super elevation Not to exceed 6% o Cross Slope 0.02 foot per foot 7-6 o Clearing and Stripping 5 ft from edge of cut slope or 10 ft from toe of fill o Surfacing 2.in. minus gravel o Culverts '24 in minimum CMP Construction of the access roads is important in order to allow the movement of equipment, men and material throughout the project site. To permit the earliest commercial operation dates for the project, it is necessary to construct the roads in one season. To accomplish this schedule the roads must be constructed concurrently, and in the case of the road between the lower camp and the dam, from several staging locations enroute with helicopter support to accelerate progress. The development of an airstrip is proposed under the recommended plan. The location of the airstrip as recommended by the COE, north of the powerhouse is a good general location. Further study indicates that approximately 1000 ft of road savings are possible on the airstrip access road length by locating the landing strip 500 ft closer to the powerhouse location with a runway alignment of 23/5, and locating the parking apron in a natural bay on the southern one third of the landing strip. The access road to the airstrip from the powerhouse has an overall road width of 18 ft allowing single lane traffic. An 18 feet road width provides suitable and economical access to the airstrip. The alignment follows the coastline utilizing slight cuts and associated benching. This alignment minimizes the opportunity for settlement, which could be significant in the tidal clay areas in the adjacent mud flats; and takes full advantage of the higher natural ground relief to reduce the embankment material. The access road from the powerhouse to the lower camp will be subject to high traffic volume during construction and is a two-lane road. Overall, the alignment suggested by the COE is satisfactory. The changes in the alignment that have occurred have to do with setting the powerhouse and 7-7 tunnel portal, and relocation of a section of road northeast of Sheep Point to incorporate the barge basin dredge spoil disposal area. The road design elevations provide 0. 5 ft of freeboard for the fifty year design wave. Armor is provided to prevent roadside slope deterioration on the Kachemak Bay side. At this time there is insufficient soils information available for determination of expected settlement in those portions of the access road which are located on the tidal clay deposits in the mud flats. Settlements as large as 2 ft in those areas underlaid with deep fat clay can be expected and further settlement analysis prior to final design are required. Conservative borrow quantities have been assumed, but it should be noted that 2 ft of settlement represents an increase of nearly 25 percent in borrow quantities. The magnitude of the expected settlement is related to the soil properties, layer or bedding thickness, real or apparent preconsolidation and the loads imposed. Further consolidation testing and field determination of the layer thicknesses of the fined grained soils will be necessary prior to the road embankment design. The use of Martin River borrow material for the road bed embankment has been assumed for cost estimating purposes. Ground surveyed topographic mapping with cross-sections constructed at 100 ft intervals were used to establish reliable embankment quantity take off data for cost estimating purposes. The access road from the lower to the upper camp will be subject to high traffic volume during construction of the construction diversion, main dam, spillway, and power conduit intake works. A two-lane road is recommended. The road is a combination of cut and fill type of construction. The lower section road bed along the tidal flats will be constructed with borrow material from the Martin River. The steeper relief sections will be almost entirely of cut construction to establish road benches and switchbacks in rock and then surfaced with selected Martin River borrow gravel. This access road is heavily forested between the lower camp and approximately elevation 1500. The route is characterized by steep side slopes and shallow soils over bedrock. Large quantities of rock excavation are required, but much of this excavated material can be used in the fill portions of the road, and excess cut material can be placed in areas designated as disposal areas or at switchbacks and turnouts. Based upon preliminary examination no avalanche hazards have been identified, but more 7-8 investigation is required. It is anticipated that this road would be constructed in stages to allow early access to the dam site. The initial stage would be a single lane pioneer road which would be subsequently improved to the final two lane road. To expedite road construction several work areas would be established along the road route to allow accelerated cutting and grubbing and later rock excavation. The access road from the upper camp to the dam will be subject to high traffic volume during construction of the main dam, spillway and power conduit intake works. A two-lane road is recommended. This road is of cut and fill construction, and surfaced with selected Martin River borrow gravel. The route traverses intermittent areas of exposed bedrock, colluvium, talus, till, and some areas of peat bogs at the lakes and undrained depressions. Bedrock cuts will be required, and the excavated material used in fill embankment sections with excess material hauled to local designated disposal areas. A temporary haul road is required to transport granular fill, select gravels and concrete aggregate from the Martin River borrow area. The COE proposed alignment is reasonable and the location of the bridge crossing Battle Creek was not changed. After crossing Battle Creek the route stays clear of the outwash fan by following higher terrain to the east. The route continues crossing a rather large tidal flat drainage slough where use of a drainage culvert is possible. No rip rap protection or gravel top course are included. The top of the road has been located at elevation 12. The terrain on alluvial fans from Battle Creek and Martin River is approximately elevation 12, and leveling and grading along the road route will suffice for a temporary roadway surface. A single lane road is recommended in the fill/borrow road section where the natural relief is below elevation 12, all other sections of the road would have two lanes for travelway. Maintenance would be provided on a need basis. 7. 1. 4 Airstrip An airstrip is included as part of the project works to allow fixed wing access to the project. The landing strip is located north and adjacent to 7-9 the powerhouse site with a runway alignment of 23/5 as shown on Plate 4. The layout is consistent with the COE except that a parking apron is located in a natural bog on the southern one third of the landing strip. The airstrip will be designed to meet Federal Aviation Administration criteria for Utility Stage 1. The airstrip geometry is 2,200 ft long with the centerline grade at elevation 16. The runway will be gravel surfaced and will accommodate helicopters and approximately 75 percent of all gross weight fixed wing aircraft under 12,500 pounds. The selected type of airstrip appears adequate for the foundation materials, but like the roads in the tidal flats further geotechnical investigations are required to determine in situ consolidation. 7.1.5 Emergency Access Permanent Emergency Access throughout the project will be by helicopter because landing is possible along roads; parking, lay down and staging areas; and adjacent to each project structure. All-terrain vehicles including a snow cat are provided with the operations equipment to permit all weather emergency access, but these would be used as the means of last resort in view of helicopter speed and accessibility. 7. 1. 6 Permanent Maintenance The permanent operations and maintenance personnel are provided with construction heavy equipment as part of the plant operations equipment and will be able to perform normal and routine maintenance to the roads and airstrip. In the event of a major landslide, sedimentation of the access channel and barge basin, or other major unlikely event, the services of a contractor will be required. 7 .1. 7 Alternatives Alternatives for permanent site access facilities developed by the COE were reviewed and other alternates were studied. Detailed discussions of the alternatives are presented in the report prepared by R&M, included as Appendix B of this report. 7-10 7 .1. 8 General Geology This section includes a discussion of conditions at the Barge Basin, along Access Road alignments, and at the airstrip. 7 .1. 8.1 Barge Basin The boring performed in the area of the proposed barge basin, SW 83-3, was advanced ·using rotary wash techniques with'a Simco 2400 drill rig. Samples were obtained at the base of the advanced casing with either a 3" O.D. thin-wall sampler (Shelby Tube), or a 2" O.D. split-spoon sampler driven by a 140-pound hammer falling 30 inches onto the drill rods (Standard Penetration Test). Torvane shear tests and pocket penetrometer tests were performed on each Shelby Tube in the field. In addition to the sampling of Boring SW 83-3, vane shear tests were performed at two depths in the finegrained material. An additional shallow boring, numbered SW 83-3A, was drilled adjacent to Boring SW 83-3 specifically to obtain Shelby Tube samples from zones interval of Boring S\v 83-3. All of the samples obtained from the barge basin location were sealed and returned to S&W' s Fairbanks office for laboratory testing. The potential stability of the soils in the vicinity of the proposed barge basin was evaluated by a laboratory testing program on samples from the single boring location in that area. These soils consist of soft to stiff silty clay and clayey silt overlying silty and clayey sands. The sensitivity of the fine grained soils was calculated from the results of natural and remolded field vane shear tests, laboratory Torvane tests, and unconsolidated-undrained triaxial compression tests. Details of the laboratory tests are available in Appendix A. In general, sensitivity ratios between 3.0 and 8.6 were measured. In one case, a value of 1.2 was obtained. This may be anomalous since the water content of the 7-11 remolded sample was 3% below the natural content. Triaxial test (unconsolidated/undrained) maximum unit stresses (20% strain) were as follows: Undisturbed Remolded 5 psi 3.5 psi 13.5 psi 5 psi 18 psi 7 psi Plastic limits ranged between 17% and 23%, while liquid limits ranged between 24% and 32%. It appears that soil conditions are adequate to accommodate the proposed Barge Basin under normal conditions. It should be noted that it would probably be impossible to prevent slumping of this material if subjected to the forces of a large or major seismic event. The test results from soils in the vicinity of the proposed Barge Basin, while suitable for evaluation of feasibility, should not be used for design purposes. In addition to possible variation of soil types between locations in the tidal flat deposits, not all representative soil types may have been sampled or tested at this given location. 7. 1. 8. 2 Airstrip Soil conditions at the airstrip are anticipated to be similar to those at the Barge Basin, described above. Since the site is somewhat closer to the mouth of the Bradley River, slightly coarser-grained materials may be encountered. No subsurface exploration has been done at this location. 7 .1.8.3 Access Roads In general, road alignments on side slopes will involve near-total or total excavation in slightly weathered to fresh rock with only a few feet of soil cover. In valley bottoms and similar low points, glacial and/or alluvial soils up to several tens of feet thick may be encountered; in places these 7-12 may be covered by swamp-like peat deposits. While the glacial and alluvial soils should provide adequate subgrade conditions, it may be necessary to completely remove peat and associated organic deposits and replace them with a suitable fill. Roads constructed on or adjacent to the tidal flats of Kachemak Bay will encounter conditions similar to those described for the Barge Basin, above. 7-13 7 . 2 DAM AND SPILLWAY 7 .2.1 General A concrete faced rockfill dam has been selected by the project team as the most technically and economically suitable structure for increasing the storage capacity of the Bradley lake reservoir. Geologic investigations were conducted along the axis of the proposed dam and its abutments. The findings of these investigations indicate that the site conditions are favorable for construction of the rockfill dam. The proposed dam has an upstream concrete face and the conceptual design has been conservatively developed to resist all expected loads. An ungated concrete gravity ogee spillway will be located within the saddle of the right abutment and founded on bedrock. It has been designed to pass the Probable Maximum Flood without overtopping the main dam. 7.2.2 Dam and Spillway A plan of the main dam, spillway, and associated structures is shown on Plate 7. The layout and conceptual details of the dam and spillway are shown on Plates 8 and 9, respectively. The axis of the recommended dam is approximately 520 feet downstream of the lake outlet. This location and the axis orientation were selected to best utilize existing topographical features and to minimize rockfill quantities for the embankment structure. The selected location also makes effective use of previously obtained geologic data and allows for the development of the embankment within the restricted area of the river. The axis orientation offers good alignment for the upstream toe slab, and results in toe slab construction without excessive three dimensional discontinuities. In addition, the alignment balances the upstream and downstream road access requirements for construction of the dam. 7-14 The dam has a crest 18 feet wide, 610 feet long, at elevation 1190 and a height above the lowest average foundation level of 125 feet. The rockfill embankment section conceptual design is conservatively de"<aloped with selected zoned material to withstand hydrostatic, ice, earthquake, and other external loads. The dam is developed using three zones of material compacted to form upstream and downstream embankment slopes of 1. 6H: 1V. Zone 1, forming the upstream face of the rockfill, consists of selected 6 inch minus material. This zone is placed in 15 feet wide horizontal layers of one foot lifts and is compacted with heavy steel drum vibratory rollers. Zone 2 forms a highly pervious drainage band at the base of the central section of the dam. This zone is composed of selected 6 inch to 24 inch material placed in 3 foot lifts and compacted with vibratory rollers. Zone 3 is quarry material placed in 18 inch lifts and compacted with vibratory rollers. Material placement within this zone will be such as to direct the better quarry material to the upstream.,,half of the zone. Larger or oversized material will be pushed to the downstream face. A total of 362,000 cubic yards of rockfill is required in the dam. Use of the proper material gradation in these selected zones, coupled with controlled placing techniques, proper spreading and compacting, and controlled use of water to improve workability results in an embankment that is stiff and able to withstand the forces on the dam with minimum deformation. The gradation of the material within the selected zones distributes contact forces with smaller size material occupying the voids between larger rock pieces locking both into position. At the same time adequate space is provided within .the rockfill to assure high permeability for the drainage of surplus water. The upstream face of the dam consists of a parapet wall, concrete face slabs, and toe slabs. The concrete parapet wall, extending 4 feet above the dam crest, is provided with a curved upstream surface to act as a wave deflector. 7-15 The impervious upstream face is formed by a series of reinforced concrete slabs. Central face slabs have been conceptually designed as 50 foot wide monoliths. Abutment face slabs are narrower and articulated to provide freedom of movement and to accept greater deflections. The slabs are conceptually designed to have a nominal thickness of 12 inches at the top, near the parapet, varying uniformly to a maximum thickness of 18 inches at the lowest elevation of the dam. Concrete toe slabs are constructed to connect with the face slabs and to form the watertight closure between the upstream heel of the embankment and its rock foundation. A grout curtain is placed under the toe slab for a seepage cutoff in the bedrock. Approximately 8,900 cubic yards of concrete are needed in the construction of the upstream face slab of the rockfill embankment dam. This is about 11 percent of the amount that would be required for a concrete gravity dam. The smaller quantity of concrete reduces the quantity of aggregate material that would have to be taken from selected borrow areas at the Hartin River Delta. The rockfill embankment is developed in an essentially continuous operation. Haterials for its construction are readily available from quarry sources adjacent to the structure. Concrete mixes particularly suitable for cold and harsh environments will be used in the construction of these members, offering excellent resistance to freeze-thaw action, ice buildup, and strains resulting from seasonal temperature variations. An ungated concrete gravity ogee spillway is located on the saddle feature approximately 150 feet to the right of the main dam and along the same general alignment. The overall length of the spillway including abutments is approximately 220 feet of which 165 feet is provided for the overflow crest. The height from foundation level to the crest varies from SO feet at the central portion to about 15 feet at the left. The spillway is founded on bedrock with its concrete gravity abutments . keyed into the adjacent rock. It is estimated that approximately 17 feet of overburden and weathered rock will be removed in the central portion with the excavation tapering to either side. A 30 feet deep grout curtain will be developed along the spillway below foundation level and extend westward from the right abutment to the main dam. For added safety, a drainage system is provided downstream of the grout curtain. The system consists of vertical drain holes drilled into foundation rock, a collector pipe, and a lateral pipe discharging seepage into the spillway chute. Also, provisions are made to access the drain holes for cleaning or re-drilling. The spillway is similar to the COE's design with rounded abutments and an upstream sloping face. The crest is shaped and contoured to produce a gradually accelerating flow on the basis of a 10 feet design head. The spillway chute directs the discharge onto the exposed rock and into the large natural pool downstream. Erosion of the soil cover will occur, however, once the soil mantle is removed little erosion should occur in the exposed bedrock. A concrete training wall is located on the left side to direct the discharge away from the diversion tunnel outlet. The spillway chute is divided into two sections, a downward sloping section on the left, 55 feet wide, and a llO foot wide section on the right. This avoids unnecessary rock excavation and helps in dissipating the energy of the flow. Although flow velocities could be high as the flow is directed across the toe of the main dam into the streambed, heavy rip rap armor is placed in this area to avoid serious erosion. In addition, the cost estimate contains funds for model testing this aspect and includes an allowance to cover the cost of providing additional energy dissipating devices. 7.2.3 Hydraulics Hydraulic aspects of the recommended spillway are basically the same as I . those in the COE s report. The 165 foot long ogee shaped free flow crest will be capable of passing the routed Probable Maximum Flood and Standard Project Flood with 10.6 and 5.6 feet heads respectively, assuming the powerplant and permanent outlet facilities are inoperable. 7-17 Although the crest elevation has been raised 10 f·eet above the GOE' s, the effect of the increased surcharge storage of the lake at the higher elevation on the outflow discharge was found to be negligible. The flood routings are shown on Plate 18. PMF Flood routings were also made assuming one half of the total powerplant hydraulic capacity would be available in one case, and in addition, the full capacity of the permanent outlet facilities above elevation 1185 lake level in another case. The results indicate a decrease in the routed peak outflow about equivalent to the total assumed additional hydraulic capacity available, with corresponding decreases in maximum lake levels. These results are not utilized, however, as they are considered as additional freeboard safety factor for the dam. Future studies should investigate the hydraulic aspects and structural stability effects of shaping the crest on the basis of a design head less than 10 feet. This would increase the discharge efficiency of the spillway, but at the expense of increased loads due to pressure reduction on the downstream side at heads exceeding the design head. The effect on structural stability however, is expected to be minimal. 7. 2. 4 Selection of Dam Height Wave analyses were made to determine the freeboard requirements of the dam under the simultaneous occurrence of waves induced by 70 mph winds, normal maximum water level, and the passing of the Standard Project Flood (SPF). A significant wave height of 4 feet was computed for a sustained wind speed of 70 mph over a fetch distance of 1. 6 miles. The run-up induced by this wave on the upstream face of the dam combined with set up in the reservoir was estimated to be 7.5 feet. This produces a required freeboard allowance, when combined with the SPF surcharge level, of 14 feet above the spillway crest level. The crest of the dam was set 10 feet higher than the spillway crest with a 4 feet high wave deflector wall on the upstream face to provide the estimated freeboard. Maximum water level attained during passage of the Probable Maximum Flood was checked to ensure it was within the selected freeboard. 7-18 The above criteria are less severe b~lieved to be too conservative. than that used by the COE which is The combined probability of the simultaneous occurrence of the high winds aligned in the direction of the dam along the critical fetch, occurrence of a flood equivalent to twice the flood of record, and the maximum reservoir elevation is considered to be small. The reservoir regulation studies show that maximum reservoir elevation will occur predominantly in August and September, prior to the expected maximum winds. Available wind data, although limited at the site, indicates higher wind speeds in the October through April period during which time the reservoir is expected to be ice covered. Obviously, the subject of freeboard requirements is subject to the uncertainties of many combined events. The data currently being gathered at the site should be thoroughly reviewed in determining the final freeboard requirements. Analysis of the data should remove some of the uncertainty and result in a more economical structure. The recommended maximum operating pool level, which has been set equal to the spillway crest elevation of 1180, when added to the estimated freeboard requirements of 14 feet, results in a freeboard elevation of 1194 feet. Since a 4 feet high wave deflector wall will be provided on the upstream face of the dam, the dam crest elevation was set at elevation 1190. 7.2.5 Geology and Foundation Previous investigations indicate that the location of the proposed dam and intake is in an area underlain by graywacke and argillite. The U.S. Corps of Engineers have previously conducted investigations in the general area of the dam. Field checks confirm conditions delineated by the previous studies. Efforts for this study have been concentrated in the proposed intake area which differs from that considered by the COE. The current axis alignment is upstream of the COE alignment and varies from it by about 25 to 100 feet. 7-19 Since the conditions current alignment is close to at this alignment are nearly that investigated by COE, identical. Conditions and recommendations described below are derived primarily from previous studies supplemented by field observations during this investigation. Damsite exploration by the COE included eight holes spaced along the dam axis. Drilling exploration indicated an alternating sequence of argillite and graywacke along the entire dam axis. Preliminary studies indicate generally good overall rock quality. Two 45° angle holes were drilled, one on the river's left bank and one in the right saddle, with lengths of 249.9 and 201.7 feet respectively. Vertical holes at· the left abutment, left saddle, left knob, and right dam abutment and saddle penetrated 248. 3, 133.0, 246.9 and 75.1 feet of rock respectively. One short vertical hole (60 feet) was drilled in the middle of the river. The right or east abutment at the damsit·e is a continuous outcrop of massive graywacke, exhibiting poorly developed bedding, in association with thin lenses of cherty a~gillite. Bedding generally dips at high angles to the west with a strike of about N 10° E-W. Well developed joints are present; spacing varies from less than 1 feet up to 10 feet. The two major joint patterns strike N 60°-70° E and N 45°-55 W. The first has a predominant dip orientation of 65°-75° SE. Dip angles of these joint systems form an "X" and appear evenly divided between 60°-70° NE and 60°-70° SW with a few steep dips of 80°-84° NE and SW. Accessory joints are of minor importance. Overburden appears shallow, with observed depths of 5 feet or less. A number of minor shear zones or joint swarms were observed in the general area. The largest of these is located on the north flank of the left abutment knob, approximately 150 feet SW of the downstream end of the small rock island. This fault strikes N 4° E and dips vertically. The shear zone ranges from 1 to 15 inches wide and contains a small amount of clayey, silt gouge. A crevice 15 inches to 3 feet wide is eroded 5 to 6 feet back 7-20 from the face of the rock. A possible continuance of the shear zone exists on the river side of the left abutment knob. This zone is a linear feature about 3 feet wide at the top, tapering to a soil-filled depression 2 feet wide. This feature also approximately follows a minor joint trend and has a strike of N 23° E and dips ·between 48°-59° SE. This fault is a minor structural feature and is not considered to influence the proposed location or design of the dam. Investigations in the right abutment saddle (spillway location) indicate 17+ feet of talus and overburden overlying moderately jointed, fractured graywacke. Weathering effects persist to the bottom of COE hole DH-33, (75 .1 feet). Polished, grooved, and straited bedrock· surfaces are present and are typical of areas recently vacated by ice. The right abutment appears to be satisfactory for the planned dam and spillway. Overburden on the left abutment appears generally shallower than on the .. right abutment and varies from 0.5 to 2.5 feet on the average. COE drill hole DH-35, drilled in 19 81, indicates a depth of 9. 4 feet of overburden. Unconsolidated materials appear in the saddles of both abutments. These materials include talus, sand, gravel, and topsoil. The left abutment is composed of a more argillaceous graywacke that contains thin beds of argillite and argillite-graywacke conglomerate. Aligned, pillow-shaped pieces of graywacke, in a boudinage structure, have been observed in exposed outcrops 600 feet to the south. COE drilling logs from DH-5 and DH-16 show alternating argillite and graywacke units and graywacke with various percentages of argillaceous material. Observed jointing is similar to that of the right abutment, with major joints cutting through bedding planes, striking N 55°-80° W and dipping 80° SW to vertical. Minor localized joints strike N 74° E with dips of from 78°-83° SE. The left abutment rock conditions are also considered to be satisfactory. The dam will be founded on bedrock composed chiefly of alternating sequences of argillite and graywacke. The in situ rock visible at the surface in the damsite area is all moderately hard to hard and is 7-21 considered quite adequate to support a rockfill dam. Surficial weathering is generally confined to the upper few feet of rock; however, staining on joints and fractures in the rock are potential leakage channels from the reservoir and provision must be made for seepage control. A grout curtain is required beneath the toe slab of the dam to control underseepage. 7 .2.6 Access Access to the dam is provided by the road that connects the upper reservoir area to the lower campsite, staging, and powerhouse areas. This road is aligned to also provide access for the gate shaft, described elsewhere in the report, and to other structures at the upper reservoir area. Access to the spillway will be across the crest of the rockfill dam and through a rock cut at the right aubtment. Access across the spillway agee has been eliminated. Elimnation of this access way and its required support structures results in improved discharge characteristics, lower maintenance, reduces the likelihood of structural and flow blockage problems from icing conditions, and reduces the overall cost for developing the spillway. 7 .2. 7 Alternatives The study considered the feasibility of developing a retaining dam using concrete gravity, rockfill, roller compacted concrete, and a double curvature arch dam. Preliminary study findings and conclusions were presented to the Power Authority and preferred alternatives were selected for further refinement and cost development. The roller compacted concrete dam structure was eliminated because of unknowns in the development of a suitable structure that would· provide watertight construction and adequate resistance across the rolled jointing planes to resist the seismic loads associated with the area as well as anticipated construction difficulties due to climatic conditions. The double curvature concrete arch dam was eliminated because of ecnomics. The arrangement of the concrete gravity dam is shown by Figure 6.2-2. 7-22 The two types of dams considered for detail evaluation were a concrete gravity dam and a concrete faced rockfill dam. Each type was investigated for a storage pool at elevations 1170, 1180, and 1190 project datum. Design criteria affecting dam stability, dam configurations, and engine·ering details for each dam type and size were developed and used in conceptual designs. Engineering sketches showing layouts of likely arrangement and physical dimensions of each dam type were prepared and used for quantity estimates. Cost estimates were made for each dam type and size using conceptual arrangement corresponding to each of the three different storage pool levels studied. Spillway layouts applicable to either a concrete gravity dam or a concrete faced rockfill dam, as evaluated under previous studies, were reexamined. Alternative arrangements for the development of a suitable spillway structure were also formulated and conceptualized. Technical and economic evaluations were made between these alternatives and the previ?~sly suggested spillway layouts. Study findings were discussed with the Power Authority and the preferred spillway concepts were selected for further refinement and cost development. Spillway layouts reexamined consisted of: 1) a side channel type spillway at the left abutment; 2) a side channel type spillway at the right abutment; and, 3) a spillway that would be constructed as an integral part of the dam. The first two types of spillways would be developed in conjunction with the construction of a rockfill embankment dam, while all three types would be suitable with a concrete gravity dam. Alternative spillway concepts developed under this study considered the construction of a concrete gravity chute type spillway at the right abutment saddle or the possible development of a fuse plug as a spillway. These spillway concepts would be applicable for both the concrete gravity and rockfill dam. Comparative direct cost estimates of the concrete gravity dam and the concrete faced rockfill dams, with an overflow spillway at the right abutment, showed a $4 million to $6 million differential in favor of the rockfill. The cost of the concrete faced rockfill dam with an ungated concrete ogee spillway at the right abutment was found to be the lowest of all the alternatives that were studied. The concrete faced rockfill dam 7-23 was therefore selected in the preferred scheme based upon this cost advantage, timing for construction and material needs. 7-24 7. 3 CONSTRUCTION DIVERSION 7.3.1 General Bradley Lake flows need to be diverted or handled in a manner that allows for the construction of the main dam and other associated structures within the river channel near the lake outlet. Diversion concepts perviously identified and their relationship to the development of other water conveyance and control structures were reviewed. Alternative concepts representing independent modes of flow diversion were identified and studied. The ability for providing a suitable permanent low level outlet and controlled flow releases was also studied. Environmental and construction attributes were evaluated and conceptual designs prepared for costing and economic comparisons. 7.3.2 Diversion Tunnel The recommended method for diverting Bradley Lake flows, during the construction of the main dam and other related structures, is by a short tunnel constructed through the right abutment. This concept allows for passage of flows, as they occur naturally within the drainage system, and does not require the lowering of Bradley Lake. Also, the diversion allows for the development of a low level outlet for controlled flow discharges during the life of the project, as may be required for maintenance or for downstream aquatic habitat. The diversion tunnel is an 18 foot nominal horseshoe shaped tunnel about 470 feet long and is shown by Plate 10. The tunnel is constructed during the late fall/early winter period and is advanced from the downstream portal towards Bradley Lake using drill and blast techniques. This construction time period is selected so that the diversion works. can be made operational by the spring of the following construction year. The horizontal alignment of the tunnel has been selected such that both portals can be made accessible to construction, and to respond to restraining conditions imposed by other nearby structures developed in the 7-25 adjacent areas of the river channel. The vertical alignment is established to provide the desired flow characteristics while minimizing cofferdarnming needs at the portals. Only the downstream and upstream portal areas will be lined prior to diverting flows. This is done to provide structural support and protection from erosion by flow velocities. The upstream lining is constructed as an extension of a concrete intake portal that is designed to accept steel stop logs for closure of the diversion tunnel. About 8, 300 cubic yards of material will be excavated from the diversion tunnel and its portals. Excavation for the upstream portal will be spoiled in the lake adjacent to the portal area. Material excavated from the downstream portal will be used to improve the construction working area at this portal. Tunnel excavation will be spoiled in designated waste areas near the vicinity of the dam. Subsequent· to the need for construction diversion, the tunnel will be closed off and completed with the construction of a concrete plug and by concrete lining the invert and tunnel sides up to the spring line, downstream of the concrete plug. The low level outlet with its flow regulating gates is constructed as part of the concrete plug as described herein. A grout curtain plane is developed around the concrete plug to cut off seepage flows. The plane is oriented to connect with or complement similar grout cut off systems developed as part of the spillway and dam structures. The tunnel between the concrete plug and the concreted upstream portal section is left unlined. The steel stop logs are removed when the concreting is completed and the diversion tunnel becomes a low level outlet. A heavy grillage or other protective device is provided at the outlet of the tunnel to prevent large animals from using the tunnel as a habitat area. 7.3.3 Permanent Outlet Facilities The permanent outlet facilities and fish bypass system is constructed as part of the diversion tunnel concrete plug. The low level outlet consists of two 3.5 feet wide by 5.5 feet high sluicing conduits built at the tunnel invert and extending the full length of the concrete plug. Each sluicing 7-26 conduit is provided with two hydraulically operated slide gates. Within each sluiceway one gate is considered active and is operated to regulate flow. The second gate is used in an emergency and if maintenance is required to the active gate. 7.3.4 Hydraulics The diversion scheme developed in this study is based on the need to safely pass the routed peak discharge of a flood which could reasonably be expected to occur during the time period which the diversion facilities would be in operation. The COE study utilized the 1979 flood of record as the inflow design flood for its diversion scheme. This flood had an average daily peak discharge of 5210 cfs and an instantaneous peak discharge of 6200 cfs. An inspection of the COE flood frequency curve indicates a flood of this magnitude would .'\' have a probability of being equaled or exceeded of about 10% in any given year on the average. The Construction sequence developed in the present study will require the diversion tunnel to be operational for a period of up to two years. The 1979 flood would therefore have a probability of occurring in this two year period of about 20 percent. Stated otherwise, there is a 80 to 90 percent chance that a flood with a peak discharge of 6200 cfs would not be exceeded during the required diversion period. Based on this, past experience and judgement, and the relatively short period of recorded flows used in evaluating the probabilities, the 1979 flood was chosen as the design flood for construction diversion. The 1979 flood flows were recorded at the lake outlet under natural stream conditions. Because of this it was necessary to adjust the recorded discharge hydrograph to reflect the regulation effect df the lake in determining the actual inflow. This adjustment was made by reverse routing the recorded outflow hydrograph and smoothing the resulting estimated inflow hydrograph shape until it resulted in the recorded hydrograph when rerouted through the lake. The estimated inflow and recorded discharge at 7-27 the lake outlet are shown in Figure 7. 3-1. An maximum inflow of 6800 cfs was estimated to cause the 6200 cfs to result at the lake outlet with a lake level at elevation 1088.5. The inflow hydrograph thus obtained was then routed by the lake through the diversion tunnel to determine the peak discharge and surcharge level of the lake. The results of the routing are shown on Figure 7.3-2. It can be seen that the peak inflow is attenuated considerably from 6800 cfs to 4000 cfs but the lake level surcharges to elevation 1096.5 reflecting the smaller discharge capability of the diversion tunnel over the natural lake outlet. Based on this surcharge level, the top of the upstream cofferdam and the bottom of the lowest excavated bench for the dam quarry were set at elevation 1100 providing 3.5 feet of freeboard. From a hydraulic standpoint, a large range of tunnel sizes could be constructed tvhich would pass the design flood. The only practical differences between the different sizes would be the level the lake would rise to provide the hydraulic head required to pass the peak discharge. Smaller size tunnels would result in excessively high lake surcharge levels which would require very high cofferdams at the lake outlet. The selected tunnel size will satisfy the hydrologic criteria and result in a reasonable size cofferdam. The diversion tunnel was sized to pass the routed peak discharge of 4000 cfs under open channel flow conditions. To minimize tailwater encroachment and provide additional construction work area at the outlet portal a small pilot channel will be excavated in the downstream river bed which will lower the water level in the large natural stilling pool about 3 feet. The stream channel rating curve is. shown in Plate 21 and is based on the COE rating curve adjusted for at the lower flows to reflect the lower water levels in the channel. 7-28 Permanent outlet facilities will be incorporated as part of the diversion tunnel after construction. The two sluice conduits within the concrete plug of the diversion tunnel were sized on the basis of providing a minimum flow to satisfy instream flow requirements and provide sufficient flow capacity for reservoir drawdown. The facilities are capable of passing about 150 cfs at the minimum operating lake elevation of 1080 and a maximum flow of 2750 cfs at the maximum elevation 1180. Flow through the conduits will change from open channel to orifice flow at a discharge of about 300 cfs with a small hydraulic jump occurring upstream of the plug at the lower discharges. The rating curve for the permanent outlet facilities is shown in Plate 21 and represents the flow capacity with both sluice gates fully open. 7.3.5 Geology The construction diversion tunnel will be excavated in the right abutment, passing beneath the left edge of the spillway structure. The tunnel and portals will be located wholly in massive graywacke with occasional thin lenses of cherty argillite. This is a sound rock presenting favorable tunneling conditions. Major joint orientations are also generally favorable, intersecting the alignment at about 35°-45° and ?5°-85°; dip angles range from 60° to vertical. Joint spacing ranges from one to. ten feet; in relation to the tunnel diameter (19 ft horseshoe) this will yield somewhat blocky ground conditions. A few minor, high-angle shears or faults are anticipated but are not expected to exceed about 1. 5 feet in width and are not expected to require any unusual support techniques. In summary, geologic conditions for the diversion facility are considered to be favorable. 7.3.6 Structures and Appurtenances A sluice gate control and equipment house is provided at ground level near the vertical projection of the diversion tunnel's concrete plug. This structure contains the hydraulic power pack unit and the air-oil accumulators needed to actuate the sluice gate hydraulic cylinders. Both manual and automatic gate control is provided. Manual control is available 7-29 from a control panel within the house as well as from a portable hydraulic pump at the hydraulic cylinder area. Automatic control is available from a control panel in the gate house or from the main powerplant. Telemetering equipment are provided to receive control signals and transmit gate position data to the powerplant. Electrical power is provided by long life batteries and a propane generator. The air-oil accumulators are sized to allow for one close-open-close cycle of the active gate and one close-open-close cycle of the emergency gate, before recharging is required. The proposed generator is used to recharge the batteries and to operate the hydraulic power pack pump motor. Also, this unit will be used to provide electric power for lighting the tunnel area, as may be required for inspection and during maintenance. Electrical, control, communication, and hydraulic line systems are brought from the sluice gate control house to the gate area and the tunnel through a suitably sized hole drilled to connect the two structures. 7 .3. 7 Access Access to the construction diversion tunnel and low level outlet sluice gates is provided across the crest of the downstream cofferdam. Access within the downstream tunnel section is by a steel walkway suspended from the tunnel crown and braced against the spring line. Access to the sluice gate control house is from the crest of the main dam. The upstream stop log structure is accessible from the lake by. use of a barge facility. The tunnel section, upstream of the concrete plug can be accessed either through the sluiceways, with the steel stop logs in place, or through the sluiceways and reservoir area, when the power pool is drawn down to its minimum emergency level at elevation 1,060. 7.3.8 Alternatives The COE investigated two alternative diversion schemes to their recommended plan of bypassing the natural inflow through the power tunnel and returning it to the stream through a branch tunnel downstream. One alternative consisted of diverting water through a portion of the existing lake outlet 7-30 channel while constructing the dam in the dry streambed behind cellular cofferdams. This was abandoned due to excessively high cofferdam requirements. SWEC agrees that this scheme is impractical. The other scheme studied by the COE involved a pressure tunnel through the right abutment and this was also discarded due to excessive cofferdam heights. SWEC agrees that a pressure tunnel would not be feasible at this site. The COE recommended diversion scheme was also discarded in this study since it is an integral part of the power conduit arrangement which has been abandoned for other reasons. Several other diversion schemes reviewed in this study included tunnel arrangements through the right and left abutments at the lake outlet, and a buried conduit through the main river channel. Arrangements through the left abutment with variations in details were abandoned due to interference with other structures, impacts on the construction schedule, and excessive costs. The buried conduit scheme through the main river channel was also discarded due to excessive costs, technical difficulties in constructing a suitable inta~e structure, and excessive cofferdam heights. An alignment through the right abutment was judged the best in terms of satisfying both temporary diversion capabilities and permanent low level outlet requirements. Initial concepts included analyzing 16 and 18 foot diameter horseshoe shaped fully.lined tunnels. The 16 foot diameter tunnel was abandoned because it was judged too small to ensure proper hydraulic performance while passing the design flood and resulted in larger cofferdam sizes which would encroach on the available construction working areas for the permanent structures. The 18 foot diameter fully lined tunnel was found acceptable in meeting the various criteria and was initially adopted. However, further studies indicated that use of an initially unlined tunnel for diversion during construction would enhance construction scheduling needs and would be more economical. Partial concrete lining of the tunnel would be done subsequent to diversion. This concept was subsequently adopted for the recommended plan. 7-31 7 . 4 POWER CONDUIT SYSTEM 7.4.1 General The power conduit is defined as the water passage structures that are used to bring water from the Bradley Lake to the turbine-generator units. These structures include the intake channel, the power intake, the gate shaft, the power tunnel and steel liner, and the penstock. Previously identified concepts were reviewed and new concepts developed for study. The new concepts considered relocating the power conduit intake to the left abutment area, straightening the power tunnel alignment, and placing the majority of the tunnel at a level which provides over 1000 feet of rock cover for resisting the internal pressures. The merits of lowering the tunnel to eliminate the long exposed penstock along the mountain slope were evaluated. The feasibility of using a tunnel boring machine was investigated arid economic analyses were performed to determine hydraulic losses and economic diameters of the water flow conduit sections. Hydraulic transient analyses were performed to determine pressure characteristics and surge shaft requirements under full load rejection and acceptance conditions. Consideration was given to underground surge chamber. These studies and economic alternative turbine types concluded that a surge shaft is suppress hydraulic transients under the preferred plan. a pressurized comparisons of not required to The water conveyance structures forming the power conduit are described in detail in the write-up which follows. 7-32 7.4.2 Power Conduit System 7. 4. 2. 1 Intake Channel The intake channel developed for the preferred plan is excavated as part of the rockfill dam quarrying operations. The channel is approximately 360 feet long and 50 feet wide at its base. The channel connects the power tunnel intake structure and Bradley Lake and is shown on Plates 7 and 11. During construction of the channel and other power conduit structures, water would be blocked from entering the work area by a rock plug; a large unexcavated rock section at the lake end of the channel. An invert at elevation 1,030 is selected and allows drawing the reservoir down to elevation 1, 060, as may be required for maintenance of the dam or for additional generation under emergency conditions. This minimum drawdown elevation is selected to provide adequate submergence of the intake structure and for keeping the water flow velocity in the channel to JL.less than 1 fps during full power generation. The low velocity reduces hydraulic losses; minimizes the attraction of waterlogged debris; and, allows for the build up of an ice layer which is desirable to preclude the development of frazil and anchor ice within the channel. Rock traps are being provided along the length of the channel and in front of the intake structure to retain loose rocks that may fall from the excavated slop~s or may be transported by ice. About 74,000 cubic yards of material will be excavated to form the intake channel. Of this, over 52,000 cubic yards will be used as part of the dam rockfill. Of the remaining 22,000 cubic yards, about 12,500 cubic yards of excavation is from the rock plug cofferdam. Most of this material will be excavated in a manner that will place the material in the lake area adjacent . to the channel to form a protective rock-mantle along the lake shoreline. The remaining excavation will be spoiled in waste areas designated in the vicinity of the dam. 7 .4.2.2 Intake Structure The intake is a concrete lined structure shaped to form a gradual contracting transition, varying from a rectangular shape at the intake channel to a full circular section where it connects with the upper section 7-33 of the power tunnel, Plate 12. The intake is formed by a 490 cubic yard excavation along the side of the intake channel. The total transitional length of the intake is about 42 feet. Removable trash racks are provided at the inlet to prevent floating debris from entering the power tunnel. The total gross area of the trash racks is about 460 square feet, resulting in an average velocity through the trash racks of less than 3 pfs, at full power flow. The trash racks are supported in guides at the sides of the intake structure and by a vertical concrete pier located at the upstream center of the structure. The trash rack guide system is designed to accept steel stop logs should the need arise. Access to the trash rack is by barge from the lake, at high reservoir levels, or directly by crane from the adjacent quarry benches, when the reservoir is drawn below elevation 1, 100. The entire intake is submerged below the minimum emergency drawdown pool of elevation 1,060 to prevent air entrainment during generation. However, it is recommended that hydraulic model tests be performed of the intake channel and the intake structure to determine acceptable flow conditions. 7 .4.2.3 Gate Shaft Emergency closure of the power conduit is provided by two hydraulically operated slide gates located in a gate shaft. The gate shaft, shown on Plate 11, is a vertical, concrete lined, circular shaft with an internal diameter of 22 feet. The shaft is located over the tunnel alignment, about 800 feet downstream of the intake portal. The top of the shaft is at elevation 1203 feet and the shaft extends into the ground for about 173 feet, to the invert of the power tunnel. The shaft will be developed by raised boring and slashing. About 2,500 cubic yards of material excavated to form the shaft will be spoiled in the waste areas designated in the vicinity of the dam. The concrete lined shaft will form a dry well for the two hydrauLically operated slide gates and other equipment. The gates, each 9 feet wide by 11 feet high are installed in tandem. The downstream gate is considered 7-34 the active gate and will be used in the event of an emergency to close off flow in the power tunnel. The upstream gate is considered passive and is primarily used when there is a need to service the downstream gate. Both gates will be used when maintenance of the power tunnel conduit is required. An access way is provided downstream of the active gate to allow entrance to the power tunnel. Suitable venting is also provided on the downstream side of each gate to vent the water passages to above ground level. Access to the hydraulic cylinders and gate area is provided by spiral stairs or other suitable means. A platformed area is provided at elevation 1170 for major maintenance to the gates. This platform is made from structural steel shapes with grating and checkered plate covering. Access to the gates and to the maintenance platform is through openings at the top of the gate shaft structure. An equipment platform, of similar construction, is provided at elevation 1190. This platform will support the equipment needed to control, mon~tor, and operate the gates such as: a control panel for manual and remote ,gate operation; long life battery and propane generator; the hydraul:i,c power pack and air-oil accumulators; and, other telemetering and communications equipment. Separate air-oil accumulators are provided for each gate. These are sized to allow one closeopen-close cycle before recharging is required by the hydraulic power pack. The propane generator is sized to provide the power needed by the power pack for lighting within the gate shaft during maintenance and for recharging the battery. Access to the gate shaft from the outside is provided by a concrete stairwell, leading to the equipment platform, and by a steel stairway that connects the two platformed levels. 7 .4.2.4 Power Tunnel The power tunnel is an 11 foot nominal diameter, concrete lined, circular conduit as shown on Plate 12. Starting at the intake, the tunnel extends horizontally downstream for about 950 feet to a 38 feet long bend that connects to a 810 feet long concrete lined shaft inclined at 55° with the horizontal. A similar bend connects the inclined shaft to the main power tunnel. The main power tunnel is 16,850 feet long and includes a 2, 400 7-35 feet concrete and steel lined section. The invert of the tunnel at the downstream portal is set at elevation 42 feet. The vertical alignment of the main tunnel was limited to a grade of 1 foot in 600 feet for safety of personnel during mucking operations and to enhance the productivity of its excavation. A minimum of one foot thick concrete lining is used throughout the entire tunnel length, including the steel lined section, the inclined shaft, and the upper horizontal section. Reinforcing is provided within the concrete lined sections along the lengths crossing known faults and at the lower and upper bends. The steel lined section of the tunnel is not reinforced. The power tunnel is developed by drill ·and blast techniques, raised boring techniques, and by the use of a tunnel boring machine (TBM), as appropriate. The main power tunnel is advanced from the downstream portal located near the powerhouse area. The first 100 to 300 feet is excavated by the drill and blast method. This is done to enhance the construction schedule and to develop a good headi~g for the TBM. The heading is supported by steel sets and rock bolts. The remaining tunnel length, up to and just beyond the lower elbow; is excavated with the TBM. Fault crossings may be excavated by the TBM or conventional drill and blast methods, depending on the rock conditions encountered. It is anticipated that rock bolting and/or use of steel sets will be required at the fault areas. Some rock bolting may be required in the remaining length of the tunnel for safety reasons. The area at the lower elbow is to be enlarged to accommodate equipment during mucking operations for the inclined shaft. The inclined shaft is developed by the raised bore method. Under the present concept, a pilot hole is to be drilled from ground surface, at an inclination of 55° with the horizontal, to intercept the upper end of the main tunnel near the lower bend. This pilot hole is enlarged to a suitable diameter and serves as an opening for the torque shaft of the raise boring machine. The shaft is then excavated by a series of reaming operations using increasingly larger size raise bore bit assemblies, until the desired excavated diameter of about 13 feet is reached. The full 13 feet excavated diameter is carried up to and just beyond the projected intersection of the inclined shaft and the upper horizontal tunnel. This intersection area is then excavated and shaped to form the upper bend of the power conduit. 7-36 About 89,300 cubic yards of material is excavated from the main power tunnel, the bends and the inclined shaft. This material will be spoiled as fill in the construction of the airstrip, or as road topping on the powerhouse access road or both. The upper horizontal tunnel section of the power tunnel is developed using drill and blast methods and connects the intake structures and the inclined shaft. Material excavated from this section will be spoiled in the designated waste areas, near the dam or may be used in the dam. 7.4.2.5 Steel ~iner and Penstock The 11 feet outside diameter steel liner will be approximately 2,400 feet in length. Preliminary data and discussions with steel and penstock fabricators indicate that the steel lining can be constructed from high strength steel plates such as ASTM 517 or ASTM A710. An investigatio_p. of these materials showed that the A710 steel, with yield strengths of better than 85,000 psi and other desirable characteristics, can be considered for use. The steel liner has been · conceptually designed to satisfy the following conditions: o The steel liner will be terminated within the tunnel at a point where the rock cover around the liner is about one half of the transient pressure head. o The steel liner will be checked against possible buckling failure from an external hydrostatic pressure equal to the height of rock cover above the liner. Required shell thickness shall be based on the Amstutz theory of failure, assuming 0. 03% initial gap and a minimum safety factor of 1.2. o The maximum hoop stress will be limited to 50 percent of yield strength, assuming no support is provided by the concrete and rock. Using the above criteria, shell thickness varying from 3/4 inch to 1 inch were calculated for the steel liner, resulting in a total material weight 7-37 of 1, 380 tons. In the final design, detailed analyses will consider the assistance of the surrounding rock mass for resisting the internal pressure. The interior of the steel liner is painted with an acceptable paint system. The steel penstock section begins at the downstream end of the steel liner and terminates at the upstream end of the spherical valve of each turbine unit. The penstock consists of a roll-out section, a reverse bend section, a straight pipe section, a reducing wye, two reducing bends and two cylindrical shells connecting to spherical valves. The overall length of the penstock is about 135 feet. The roll-out section is about 11 feet long. It is stiffened by two end girders which also serve as the sliding supports of the section. The roll-out section is coupled to the steel liner and downstream penstock by specially designed high pressure couplings. The roll-out section is provided to allow for access into the tunnel section, should major maintenance be required. A man-door is provided on the side of the roll-out section for routine inspections of the tun...TJ.el. The wye section is of the internal splitter design. This eliminates the heavy external reinforcements and results in reduced hydraulic losses. The wye configuration results in two outlet branches each 8 feet in diameter. These outlets are connected to the corresponding units spherical valves by an 8 feet diameter straight penstock section, a reducing bend with an outlet diameter of 5 feet, and a 5 feet diameter straight section that is about 25 feet long. The wye and other downstream penstock members are conservatively sized to withstand the maximum internal transient pressure with an allowable hoop stress equal to less than 40 percent of yield. Both the interior and exterior surfaces of the penstock, including the roll-out section are painted with an acceptable paint system. Also, the penstock sections, downstream of the roll-out section, are encased in reinforced concrete. Part of this concrete encasement is provided by a large thrust block at the upper bend of the penstock designed to resist hydrostatic and dynamic loads. In addition to concrete encasement, the penstock sections downstream of the thrust block are placed in a rock 7-38 trench cut below the yard grade of elevation 40. This type of construction affords protection of the penstock from the elements and other factors, improves the aesthetics of the project, and more importantly eliminates the possibility of vibrations along the penstock length. 7. 4. 3 Hydraulics The power conduit system consists of the intake channel, intake structure, gate shaft, and pressure tunnel. The intake channel will be excavated in rock and has been sized to maintain average flow velocities of less than 1 fps under full power operation at the minimum drawdown level elevation 1060. This low velocity will result in negligible hydraulic losses in the channel. When the lake level is drawn below elevation 1100 all flow will be constricted to the 50 foot wide intake channel. Although velocities will be quite low there is the potential for eddy formation within the channel due to the oblique flow condition from the lake into the channel. To ensure satisfactory hydraulic performance under those conditions, a physical hydraulic model of the flow phenomenon will be conducted. The cost of this study is included in the estimate. The intake structure is of a conventional type with an bellmouth shaped roof and uniform transitioned side walls. It has been sized to maintain average velocities of about 3 fps at full power output. This low velocity will result in relatively minimal hydraulic losses within the intake and across the trash racks. Vortex formation at the intake should not occur under normal power operations. The intake invert has been set 30 feet below the minimum drawdown elevation of 1060 which is based on past experience in a large number of projects. However, as an added safety factor, the physical model discussed above will include the intake structure to study vortex formation under adverse conditions. The gate shaft structure will house the rectangular slide gates with a smooth transition from the circular pressure tunnel. Losses in this section will also be minor. Other minor losses will occur in the various bends of the power tunnel and penstock. 7-39 Of the total hydraulic losses in the system, the largest will occur due to friction. It has been estimated that the combined friction and minor losses will vary between less than one foot under minimum power operation to about 55 feet under maximum power generation. The hydraulic losses are calculated ·as : H1 = 3.22 x 10-5 (Q 2 ), where H1 is the loss in feet and Q is the flow in cubic feet per second. 7.4.4 Transient Analysis Transient studies were performed for each project capacity studied, 60, 90, and 135 MW; and each type of turbine, Francis or Pelton. The objective of these studies was to determine the maximum and minimum pressures in the power conduit during full plant load rejection and load acceptance, and identify surge facility requirements. The transient analysis was performed using the SWEC Hydraulic Transient Analysis Program HY-001. The power conduit arrangement varied with each type of turbine and capacity which required that each type of turbine and capacity be analyzed as an individual case. For the purposes of the transient analysis the Francis turbine runner was set at elevation -6. The power conduit was 10, 11, and 12 feet in diameter for capacities of 60, 90, and 135 MW, respectively. The following is a description of the modeled power conduit: A-B B-C C-D Segment D-E E-F F-G Description Powerhouse --2 units Steel penstock Steel and concrete lined tunnel Concrete lined tunnel Surge tank Concrete lined tunnel Concrete lined inclined shaft Concrete lined tunnel Intake (invert elevation 1,040) Length 200 feet 2,600 feet 1,700 feet 12,950 feet 850 feet 650 feet During initial computer runs, varying surge tank diameters and orifices diameters in the riser shaft to the surge tank were tried. Transient pressures were reduced upstream of the surge tank, but remained high downstream in the steel lined tunnel section and penstock. Synchronous bypass valves were added to the computer model upstream of the turbine scroll case and the transient analysis was repeated; the transient pressures were significantly reduced downstream of the surge tank. Figure 7.4-1 shown the maximum transient pressure gradient and Table 7.4-1 shows the respective maximum and minimum pressures at various powerhouse capacities, synchronous bypass valve sizes, and wicket gate opening and closure times. There was no water column separation indicated during either full load acceptance or reJection for the cases depicted in the Table 7 .4-1. The full load acceptance was modeled at minimum headwater elevation and the full load rejection at maximum headwater elevation. The Pelton turbine runner was set at elevation 14, 15, and 16 feet, an~ the power conduit w~s 10, 11, and 12 feet in diameter, for capacities of 60, 90, and 135 MW, respectively. modeled power conduit: The following is a description of the Segment Description Length Powerhouse --2 units A-B Steel penstock 200 feet B-C Steel and concrete lined tunnel 2,600 feet C-D Concrete lined tunnel 14,650 feet D-E Concrete lined inclined shaft 850 feet E-F Concrete lined tunnel 650 feet Intake (invert elevation 1,040) The power conduit was modeled without a surge tank with needle valve opening times of 35 and 60 seconds and closing times of 60 seconds. The computer rs results indicated acceptable transient pressures exist in the pow~r conduit under these cases. The needle valves are commonly equipped with a hydraulic cylinder operated deflector which deflects the jet from the Pelton runner during the load rejection. Once the jet is deflected the 7-41 needle valve can be closed at a gradual rate such as 60 seconds. Figure 7. 4-2 shows the maximum transient pressure gradient and Table 7. 4-2 shows the respective maximum and minimum pressures at various powerhouse capacities, and needle valve opening and closure times. There was no water column separation experienced during either full load acceptance or rejection for the cases depicted in the Table. The full load acceptance was modeled at minimum. headwater elevation and the full load rejection at maximum headwater elevation. The transient results indicate that a surge tank is not required. 7 .4.5 Geology This section includes outlines of geologic conditions at the Intake Structure and for the various segments of the Power Conduit System; these subdivisions are based on geologic terrain rather than design elements. Also included are the results of laboratory tests on selected rock cores and an outline ·of the results of petrographic examination of the various rock types present. Details of geologic conditions are available in Appendix A. 7 . 4. 5. 1 Intake Area Surface reconnaissance reveals that the rock is comprised of complexly mixed graywacke and foliated argillite with less than 10 percent chert nodules and layers. The contacts between the graywacke and argillite roughly parallel the foliation in the argillite, which typically trends N-S to N20°E and dips steeply. Several small faults and joint sets are present. These features have been described in some detail by Woodward-Clyde (1979) and Dowl Engineers (1983) as part of their investigations for the left abutment of the dam. No faults are known to intersect the currently proposed location for the intake portal. An east-northeast-trending topographic lineament, which passes near the proposed location of the intake portal, was suspected to be the surface expression of an east-northeast-trending rockmass discontinuity. This lineament is the gully between Hill 1270.7 and Hill 1525.6. About 1, 000 7-42 feet to the west of Bradley River the lineament merges with an east-trending fault mapped by Woodward-Clyde (1979). Directly east across Bradley River, it trends into the vicinity of two small covered areas which are probably the surface expression of joints or small faults. The lineament also parallels an east-trending fault located about 250 feet to the north on the east side of the river, and a series of lineaments, of unknown origin, to the southwest. Boring SW83-2, oriented S6°W and angled at 45°, was made to define subsurface conditions causing the prominent lineament. The boring was oriented to cross the lineament described above and encountered 28.4 feet of colluvium and 126. 9 feet of bedrock (20. 1 feet and 89. 7 feet vertical depth). Bedrock is primarily graywacke with varying amounts of associated argillite; the overall rock mass fabric appears to be cataclastic in origin. Close to very close jointing was encountered in portions of the boring; no indications of significant faulting were found. Since the feature sampled by Boring SW83-2 is the most prominent lineament in the Intake area, it is considered that the Intake facilities should not encounter any significant faults or shear zones. Several minor shears have been previously mapped in the Intake area (Woodward-Clyde, 1979). These are well exposed and are not known to exceed one to two feet in width. Several of these may be expected to cross the Intake channel but are not considered significant to construction or operation of the facil'ity. Geologic conditions arEa considered to be satisfactory for construction of the proposed Intake facilities. 7 .4.5.2 Bradley Lake to Bradley River Fault Zone This easternmost section interbedded gray-wacke and of th~ tunnel alignment is argillite. Because of their been mapped as a single unit percent massive graywacke and 35 these rock types have approximately 50 to 65 under lain by complex mixing, comprised of to 50 percent argillite. The argillite is commonly foliated and occurs as interbeds and pockets that range from less than a foot to as much as 100 feet thick. 7-43. Jointing is more apparent along this section of the tunnel alignment than further to the northwest. Several lineaments also cross this section of the tunnel alignment at various orientations. It is suspected that some of these features may be faults, but there is generally insufficient rock exposure to determine whether they represent faults or major joints. One pair of parallel lineaments, located about 1, 700 feet northwest of the intake structure is particularly suggestive of a fault zone. Their origin is uncertain; if they are the surface expression of a fault, the zone may contain highly fractured and crushed rock up to about 200 feet wide along the proposed tunnel alignment. 7 .4.5.3 Bradley River Fault Zone At a distance of approximately 3, 900 feet from the intake, the tunnel alignment crosses the Bradley River Fault zone. The main trace, can be followed for several miles along a trend of about N15 °E. The fault is mantled by colluvial and glacial deposits, but is believed to be nearly vertical because of its linear topographic expression. Exposures elsewhere along the Bradley River Fault have suggested that the main fault trace can have a gouge zone of finely pulverized material that is up to 50 feet wide, with sheared argillite extending another 50 to 75 feet on either side (Dowl Engineers, 1983). The Bradley River Fault zone was explored by boring SW83-2, which was drilled perpendicular to the fault trace at an orientation of N75°W and at an angle of 45°. Drilled to a depth of 262.3 feet, the boring penetrated two shear zones at 47.4 62.0 feet and 138.0 175.6 feet, possibly representing branches of the fault. From the surface to a drilled depth of about 30 feet, loose gravelly sands with cobbles and boulders were encountered above bedrock. Striations observed on a cobble suggested that these materials are, at least in part, glacial. Beginning at the top of bedrock, shear-foliated cherty argillite was encountered, and encompassing the two shear zones, continued to a drilled 7-44 depth of about 197 feet. This rock is closely jointed to locally very closely jointed. Below a depth of 197 feet, alternating zones of graywacke and chert were encountered, with local zones of cherty argillite and foliated argillite. Joint spacings in these materials increase to moderately widely spaced joints when argillite materials are not significantly present. It is possible that additional shear zones exist to the east of the upper one encountered in boring SW83-2. The material observed in similar zones is predominantly brecciated argillite rock Locally the rock has been reduced to fault fragments in a clayey silt matrix. containing clasts of chert. gouge consisting of breccia The cherty argillite adjacent to the shear zones is generally very closely jointed and the argillite faces adjoining shear planes are extremely : ·~ slickensided, often containing crushed rock fragments as breccia and goug~. The amount and sense of displacement along the Bradley River Fault zone is not well established. Slickensides rake from 0 to 30° along the fault suggesting a vertical component of up to 400 feet associated with the i,OOO feet of apparent horizontal displacement. Horizontal offset of a dacite tends to confirm this. 7 .4.5 .4 Bradley River Fault Zone to Bull Moose Fault Zone Northwest of the Bradley River Fault zone, the tunnel alignment crosses the highest elevations and best exposed bedrock along its route. This area is underlain predominantly by foliated argillite, with lesser amounts of massive _argillite, graywacke, and a single dacite dike. Much of the foliated argillite contains nodules and thin discontinuous layers of chert comprising about 10 to 20 percent of the volume of the rock. A few massive lenses of very closely fractured chert up to 10 feet wide were also found interspersed with the foliated argillite in this area. . The foliation in the argillite and cherty argillite strikes from N-S to N20°E and typically dips greater than about 75 degrees. The dacite dike, although not exposed 7-45 on the alignment itself, appears to cross the proposed tunnel alignment along a N80°E trend with a nearly vertical dip. For tunneling purposes this rock will probably behave similarly to the massive argillite or graywacke. Bedrock outcrops along this segment of the tunnel alignment tend to be widely to very widely jointed. Hundreds of short, linear, soil-filled depressions can be seen in this area, many of which are presumably the surface expression of bedrock joints and/or minor faults. Unfortunately, however, without better rock exposure it is not possible to distinguish which of these features are faults or joints. Larger lineaments, also common in this area, present the same problem for attempts to define their structural significance. A series of lineaments, occupying an area about 1,000 feet wide, located east of and subparallel to the Bull Moose fault zone are possibly the surface expression of smaller faults associated with the main fault trace, but exposures are insufficient .to conclusively determine their origin. In spite of relatively good rock exposure in this area, it was not possible to determine conclusively whether these represent minor faults or prominent joint sets. In either case, exposures limit the width of these apparent discontinuities, at the surface, to less than about 10 to 15 feet where they cross the tunnel alignment. 7 .4.5.5 Bull Moose Fault Zone The main trace of the Bull Moose fault zone is located approximat~ly 9,800 feet northwest of the tunnel intake. It is expressed as a narrow, topographic notch with a 200-foot-high, steep west wall. This area is densely vegetated and rock is exposed only in small isolated outcrops. No exposures of the crush zone in the fault were found, but relatively undeformed rock on either side of the main fault trace indicates that this zone must locally be less than about 50 feet thick. The tunnel alignment crossing of the Bull Moose Fault was explored with boring SW 83-4. Drilled at an orientation of N80°W and an inclination of 45°, this boring was carried to a depth of 206.2 feet. 7-46 Bedrock was encountered after only 4. 2 feet of penetration, and the shear zone of the Bull Moose Fault was encountered at a drilled depth of about 146 feet. Random alternating zones of graywacke, argillite, and chert, as well as mixtures of these lithologies were logged within the depth explored. The shear zone of the Bull Moose Fault was encountered from a depth of about 146 feet to 154 feet in the boring (horizontal width of 6 feet). The brecciated argillite and graywacke in this zone is locally sheared to silty sand and zones of clayey gouge. The rocks adjacent to the shear zone, argillite above and chert below, are highly fractured from considerable shear deformation. The vertically projected location of the shear zone encountered in boring SW83-4 is consistent with the mapped location of the fault trace for a near-vertical fault plane. 7.4.5.6 Bull Moose Fault Zone to Powerhouse Site The bedrock exposure is much more limited along this segment of the tunnel alignment than it is to the southeast. This is particularly true to the northwest of the possible surge tank location where forest and soil cover mantle all but a few small isolated rock outcrops. The available exposures indicate that this section of the tunnel alignment is underlain predominantly by foliated and massive argillite. Cherty argillite and graywacke crop out in relatively small amounts, although boring data indicate that these rock types are more common than their surface exposure suggests. The predominance of argillite is also indicated by natural outcrops visible 1000 -1500 feet southwest of the tunnel alignment in a gully which roughly parallels the alignment. The recognizable structural trends in this area conform to those elsewhere along the tunnel alignment. Foliation in the argillites is consistently oriented at N-S to N20°E. Jointing is widely to very widely spaced in most exposures, with a dominant strike of N75-85° North. 7-47 7. 4. 5. 7 Laboratory Rock Testing Selected portions of N-size rock cores recovered from COE borings were tested to define general rock strength properties and, more particularly, to ascertain the feasibility of driving the tunnel using a tunnel boring machine (TBM). Various tests were conducted by Dr. A. J. Hendron, member of the Project's Technical Review Board, and by TBM manufacturers Atlas Copco Jarva, · Inc. and The Robbins Company. In addition to this current data, the results of previous tests by the COE are included. The results of the tests, grouped by rock type, are shown on Tables 7. 4-3 through 7. 4-8. Several tests on rock from APA's Terror Lake Hydroelectric Project (Kodiak Island, AK) are included for comparison with Bradley Lake rock types. A tunnel is currently being successfully driven at Terror Lake using a TBM. It should be noted that the fabrics of rock types (with the possible exception of the dacitic dike rock) from Bradley Lake differ from that of the quartz diorite of Terror Lake. The various testing agencies conducted different types of tests and direct comparisons of results are difficult. In the case of the tests conducted by the TBM manufacturers, some test methods and all interpretation methods are proprietary. In summary, it is seen that among the major rock types the graywacke tends to yield the highest unconfined compressive strengths (up to 34,975 psi) and generally the greatest hardness (various methods). In decreasing order, following graywacke, are graywacke/argillite mixtures, massive argillite, foliated cherty argillite, and foliated argillite, which yields unconfined compressive strength in the range of 8000 -6500 psi and Total Hardness as low as 68. Chert, in large, discreet masses is very uncommon and is the only rock type judged as "abrasive" for TBM tunneling purposes. Unconfined compressive strengths for chert were fairly low, 6800 -11, 120 psi (one at 22,730 psi), reflecting both macro-and microscopic in situ fracturing; Total Hardness ran as high as 204.4. In comparison, Terror Lake quartz diorite (including even sericitized specimens) tested from 22,800 to 26,050 psi with Total Hardness from 106 to 133 (one at 74.8). Typical values for the majority of Bradley Lake specimens are very similar to values obtained from Terror Lake samples. 7-48 Advance rates for a TBM have been estimated as outlined below: Rock Type Rate (ft/hr) Estimated Tunnel Length (ft) Graywacke, Graywacke/Argillite 6-8 4300 Massive Argillite 8:-10 5000 Foliated Argillite 10-12 3500 Foliated, Cherty Argillite 8-10 3790 Chert 3.0-5.75 50 It should be noted that tunnel lengths may not correspond exactly to those given in a similar table on page 43 of Appendix A. The lengths above have been slightly revised based on petrographic data unavailable at the time of issue of Appendix A. Tunnelling conditions for fault zones, fracture zones, and at portals, where drill and blast techniques and temporary steel sets would be used, are shown in Table 7. 4-8. It is concluded that the use of a TBM for tunnel excavation is technically feasible at the Bradley Lake site. However, to support the definitive engineering and design, the characteristics of the fault formations should be determined at tunnel depth. 7. 4. 5. 8 Petrographic Examinations Thin sections were taken of selected surface specimens and portions of rock core samples. The primary purpose of these examinations was to provide a check on the megascopic field classifications assigned to various rock types during surface mapping. In a few cases, the examinations provided 7-49 clarification for rock types of uncertain origin and classification. General characteristics of the major rock types were established by rigorous petrographic analysis and the remainder of the samples identified by sight under the petrographic microscope. A list of samples, their locations and their classifications are included in Table 7. 4-9. Analysis sheets for the major rock types -graywacke, ma.ssive argillite, foliated argillite, cherty foliated argillite, and tuff (or volcanic graywacke) are included as Figures 7.4-3 through 7.4-7. Also included and shown by Figures 7.4-8 and 7.4-9, are analyses of quartz diorite and hydrothermally-altered quartz diorite from the Terror Lake project. As outlined in the section above, these samples were tested to provide a comparison of strength properties with rocks from the Bradley Lake area. With the exception of one rock type, the tuff or volcanic graywacke, thin section examination confirmed megascopic field classification of rock types. The tuff had been identified in the field as an anomalous rock type but, because of its fine-grained nature,_could not be positively classified by megascopic examination. Microscopic examination positively identified its volcanic origin but also established its grain-size distribution and probable mode of deposition as essentially the same as that of the graywacke, thus the alternate term, volcanic graywacke. Certain conditions, applicable to the general geologic setting of the site area, were noted in the thin sections. These include: o Pervasive alteration of feldspar, particularly plagioclase, to sericite. o Pervasive but low-level chloritization. o Development of cataclastic textures in virtually all clastic rock types. The degree of development roughly corresponds to grain size, with the finer-grained rocks showing more pronounced development. Petrographic examination has confirmed the validity of rock type classifications made by megascopic examination during the current field mapping program. In addition, the postulated cataclastic origin of major 7-50 rock mass and structural features is reflected at the microscopic level; taken together, it would appear that the areas has been subjected to repeated deformation. 7 .4.6 Access Access to the power conduit is powerhouse. Access within the available from the area adjacent to the power conduit is through the roll-out section, the mandoor at the roll-out section or the man access way at the gate shaft. The roll-out section affords access to large equipment should major repairs be needed within the power conduit. Mandoor access is principally for general inspection. 7.4.7 Alternatives Several alternative power conduit alignments were identified under previous t~ studies by the Corps of Engineers and dismissed for valid technical and economic considerations. The power conduit alignment selected by the COE was reviewed under this study and a comparative evaluation was made to the alignment recommended by this report. The comparison showed substantial savings and other construction environmental improvements resulting from the following: o Use of the tunnel boring machine. o Elimination of the exposed side hill penstock. o Elimination of the hillside access road to the high tunnel portal. o Elimination of the access and haul road to the bridge crossing at the upper Bradley River. o Elimination of the bridge crossing. o Elimination of the access adit to the power tunnel. o A reduction of the power conduit length. Because of the above, the decision was in favor of the preferred alignment presented by this report. 7-51 7 . 5 POWER PLANT 7.5 .1 General The powerhouse is located near sea level on the southeastern shore of Kachemak Bay at approximately N2,112,430,E327,100. The relief at the powerhouse site rises steeply from the tidal flats near elevation 10 to elevation 1400. The powerhouse and power tunnel portal are situated upon an excavated rock bench at elevation 40. This excavation has an oblonged triangular arrangement as shown on Plate 13. Local excavations below elevation 40 are required to contain the powerhouse substructure, the steel penstock, and the bifurcation and thrust block. The excavated material would be utilized to form a construc.tion laydown area and switchyard in the tidal flats adjacent to the powerhouse excavation. The powerhouse is approximately 138 feet long, 66 feet wide and 112 feet high. The powerhouse substructure is constructed of reinforced concrete detailed to be integrally keyed into the surrounding bedrock. The Pel ton turbine, inlet penstock, and manifold are entirely housed within the reinforced concrete portion of the structure. An insulated structural steel superstructure is above elevation 40 housing the generators and bridge crane. The bridge crane runway is comprised of steel columns and girders which also serve as the main structural members for the powerhouse superstructure. The powerhouse plans and elevations are shown on Plates 13 and 14. The powerhouse has two main operating floors, the turbine floor at elevation 23 and generator floor at elevation 40. Local spherical valve pits are provided below the turbine floor at elevation 5 to house the spherical valves and hydraulic cylinders. Access to the turbine chamber can be obtained from the spherical valve pit via a steel mandoor. A 16 feet wide tailrace deck is provided downstream of the powerhouse 7-52 superstructure to provide access to the turbine chamber through a deck hatch should major maintenance be required. A tailrace channel will be excavated downstream of the powerhouse through the tidal flats to allow a free discharge of generating flows to the Kachemak Bay. 7 .5.2 Basic Data Plant, KVA (nameplate rating) Number of Units Type of Turbine Turbine Rating at 1130 feet rated net head, Hp Rating of Generating Unit, KVA (nameplate) Maximum Operating Pool Elevation, feet Minimum Operating Pool Elevation, feet Maximum Tailwater Elevation, feet Minimum Tailwater Elevation, feet Centerline Turbine Runner Elevation, feet Bottom of Turbine Chamber, feet Unit Spacing, feet 7 .5.3 Tidal Considerations 112' 600 2 Pelton 73,900 56,300 1,180 1,080 11.4 -6.0 15.0 -6.0 43.0 The powerhouse setting and tailrace configuration are based upon the following range of tides developed by the COE: Highest Tide (estimated) Mean Higher High Water Mean High Water Mean Sea Level Mean Low Water Mean Lower Low Water Lowest Tide (estimated) 7-53 Elevation Based on Project Datum 11.37 4. 78 3.97 -4.02 -12.02 -13.63 -19.63 Of particular concern at the powerhouse is salt water intrusion and the resulting corrosion problems for steel and other metals. To avoid direct salt water contact with the Pelton turbine runner, the runner is set at elevation 15, 3. 6 feet above the estimated high tide level. Tailwater depression will be used to maintain free runner discharge. The tailrace deck has been set at elevation 23 with a 3.5 feet high concrete parapet wall. This will provide 15 feet of wave run-up at high tide. This setting also prevents the manifold and penstock from coming in direct contact with the salt water intruding during high tide periods. Cathodic protection is provided to protect steel and other metal components from accelerated corrosion that are near or in the salt water interface. 7.5.4 Turbines and Generators The turbines selected for the preferred plan are 6 jet Pelton vertical shaft type units direct coupled to the generators rated for a net head of 1130 feet at 300 rpm. The generating unit nominal rating is 45 MW at full 6 jet gate and at the minim~~ gross generating head of 1065 feet. The best point efficiency rating of the turbines was set at a rated head 10 feet above the weighted average net generating head. The 10 feet upward adjustment was made to better represent anticipated turbine conditions for years other than the critical period operation. operating The rated net head was also used in determining maximum full gate horsepower of the turbine. The Pelton unit is accessible and removable through the turbine chamber and tailrace hatch without requiring the dismantling of the generator. Needle valves are equipped with jet deflectors and hydraulic operators. Each of the two generators is rated 56300 KVA, 13800 volts, threephase, 60 HZ, 0.95 power factor, 300 rpm. The generators are of the vertical shaft, suspended type with a guide and thrust bearing located above the g.enerator rotor, and a guide bearing below the rotor. Generator insulation is class B or better. Winding temperature rise is 7 5 °C over a maximum ambient air temperature of 40°C. The stator winding is wye-connected, and the winding neutral is grounded through a transformer-resistor arrangement to limit 7-54 line-to-ground fault current. The generator is completely enclosed and equipped with a-C0 2 fire protection system. The generator excitation is provided by a static exciter, which consists of a three-phase transformer, rectifier and voltage regulator. Power for excitation is taken from the generator terminals. 7.5.5 Powerhouse Arrangement The powerhouse location was selected to assure that the powerhouse substructure would be located on rock and to take advantage of the natural coastal relief in order to minimize the overall excavation required to accommodate the powerhouse, penstock and tunnel portal. Field topographic surveys were conducted at the proposed powerhouse site to accurately depict the relief. Of particular importance was the interrelationship of the powerhpuse, penstock, and power tunnel and portal in determining the overall excavation size. In order to fully support the construction efforts, continued access is required to the power tunnel and portal throughout the construction schedule. Normal minimum distances around the powerhouse were increased from 40 feet to 100 feet to improve access to the tunnel portal during powerhouse and penstock construction. In addition, a lay down and storage area at elevation 20 is provided adjacent to the powerhouse excavation to support the powerhouse, penstock, and power tunnel construction activities. This lay down area will increase the staging area available to the construction contractors by 1. 2 acres and will later be used to site the powerhouse substation. The initial construction activities to establish the power tunnel portal and initiate tunneling operations with the TBM are very critical to the project schedule. Therefore, the construction of the powerhouse has been delayed until the intense tunneling effort is essentially over. The powerhouse and penstock excavation will be established at the same time that the initial powerhouse elevation 40 bench open cut excavation is established. These excavations will be back-fiLled with granular material 7-55 to increase the staging area available to the tunneling contractor. The powerhouse contractor will remove the granular material during the construction of the powerhouse and penstock. In sizing the powerhouse structure, the 90 MW Pelton generating equipment was evaluated to determine the key factors which affect the internal powerhouse layout. These are: o Manifold and Turbine Chamber o Spherical Valve Dimensions and Orientation o Generator Overall Dimensions o Size and Location of the Auxiliary Electrical and Mechanical Equipment o Control Room Size The manifold and turbine chamber dimensions are dimensions obtained from turbine manufacturer inquiries. contained and may be operated when the other unit representative of Each unit is self is dewatered for inspection or maintenance. The manifold is downstream of the spherical valve and is equipped with needle jet valves and nozzle deflectors to control flow to the Pelton runner. The manifold is of high strength welded steel construction and is embedded in a minimum of two feet of reinforced concrete. The upper turbine chamber is steel lined and hydraulically shaped to provide a free water discharge from the Pel ton runner buckets. The turbine chamber ·will be pressurized by air to depress the water surface level during periods of high tailwater resulting from tides. An air recovery system was considered but was not pursued due to the relatively short tailwater channel between the turbine chamber and the draft tube gates. This aspect should be investigated further during the final design phase and generating equipment selection. Accessibility to the turbine chamber for periodic inspection and maintenance on the Pel ton runner, needle jet valves, and subcomponents is provided. Turbine inspection can be performed through the spherical valve pit into the turbine chamber via a 3 feet wide and 5 feet high water-tight mandoor. This means of access also serves as a second means of egress from 7-56 the turbine chamber during periods of major maintenance and allows for air circulation during welding operations in the turbine chamber. The normal access for major maintenance will be through an access hatch provided at each unit and located in the elevation 23 tailrace deck. This access hatch has a 10 feet wide and 16 feet long clear opening, which is sized to accommodate the removal of the turbine runner. The turbine chamber floor is at elevation -6 requiring staging to provide vertical access to the turbine equipment located at elevation 15. The tailrace access hatch is oriented to allow a 9 feet by 15 feet by 17 feet staging to be lowered in a single piece. The staging would be equipped with rollers and a jacking table for runner installation and dismantling in the event of major maintenance. The spherical valves, hydraulic operator, power units, and accumulator, are representative of dimensions obtained from manufacturers. Each valve has a self-contained hydraulic operator which has an accumulator tank size~:: to permit a close-open-close cycle, without recharging, in the event of total power loss (station service, emergency diesel generator and battery). The power unit and accumulator tank are located on the elevation 23 floor with the spherical valve and hydraulic ram in the valve pit. The valve pit has been sized to permit access on each side of the spherical valve body for complete visual inspection and maintenance. Access is provided into the pit by a ladder on the operator side of the valve and 6 feet of headroom is provided under the penstock downstream of the valve body to permit access to the other side of the valve. A sectional covered hatch is provided over the valve pit in the floors at elevation 23 and 40 to permit bridge crane access to the valve pit. The largest generator manufacturers' dimensions were used to layout the powerhouse. This is a conservative approach and allows a powerhouse arrangement to be developed at the conceptual stage which can accomodate a variety of generator manufacturers dimensions. During the final design phase, definitive manufacturers dimensions will be available and may allow the overall dimensions to be reduced. To ease installation of the generator, a powerhouse layout was developed which permits the stator and 7-57 rotor to be delivered to the project site fully assembled. The powerhouse door adjacent to the assembly bay is· 30 feet wide and 20 feet high. The powerhouse bridge crane has been sized to accommodate both the stator and rotor lift. The size and location of the auxiliary electrical.and mechanical equipment is based upon actual project experience. Space is allowed around the equipment to permit installation and maintenance access, and allow space for egress. The floor plans at elevation 23 and 40 are shown on Plates 13 and 14. The size and location of the control room is based upon actual project experience. Space is allowed around the control panels and consoles to permit installation and maintenance, and allow two doors, one exterior and one interior, for egress. Space has been allowed for office desks, files, and cabinets within the control room. Restroom facilities are provided adjacent to the control room. 7. 5. 6 Electrical Equipment The one-line diagram for the plant, of key electrical equipment and their arrangement, is shown on Plate 22. There are two main power transformers, located in the substation, one for each generator. The transformers are each rated OA/FA/FA-33. 8/45/56.3 MVA, three-phase, 60 HZ. ·The high voltage winding is rated 115,000 volts, grounded wye, and the low voltage winding i~ rated 13,800 volts delta. The transformers are oil-immersed, with a self-cooled rating, and two stages of forced air cooling. The generator circuit breakers, potential transformers and generator surge protection are contained in 15 kV metal-clad switchgear cubicles. The generator breakers are rated 3000 A continuous, 1000 MVA interrupting capacity, and include (6) 3000/5 amp current transformers. Each generator is provided with (4) 11400-120 volt single phase potential transformers for metering, relaying, and synchronizing. The potential transformers are fused on the high and low voltage sides and are drawout type. Protection for each generator consists of three 15 kV lightning arresters and three surge capacitors mounted in a switchgear cubicle. Each of these protective devices are 7-58 connected between the generator terminals and the powerhouse ground system. Each of the switchgear groups associated with a generator is located adjacent to the generator on the operating floor level. The generators are connected to the switchgear, and then to the transformers via copper conductor, three-phase, non-segregated phase bus. The bus is rated 15000 volts, 3000 amps continuous, and 80,000 amps momentary. The portion of the bus in the powerhouse is ventilated, and the outdoor portion is fully enclosed and weatherproof. Station service power is provided by a double-ended load center. There are two dry-type transformers, rated 450 KVA, 13.8 kV-480V, threephase, 60 HZ. Each transformer is connected to the generator terminals through a 15 kV, current limiting, fused disconnecting switch and via 15 kV shielded cables. One transformer is connected to Generator No. 1 and the other transformer is connected to Generator No. 2. Due to the use of generator breakers, both station service transformers are normally energized, , .. even '~z.,_ during generator shutdown. The station service switchgear is 600V class drawout type arranged in two main buses. Each bus is provided with an 800 amp, electrically operated main circuit breaker, with an 800 amp normally open tie breaker between the buses. The tie breaker closes upon loss of voltage on either bus. Each transformer and main breaker is capable of carrying full station service load, in the event one transformer fails. Each main 480V bus has a sufficient number of manually operated switchgear type feeder breakers and potential transformers. Starter, contactors, and feeder breakers are contained in several motor control centers located strategically throughout the power plant. The motor control centers are rated 480V, three-phase, 60 HZ. Combination starters are provided for motors, each starter consisting of a molded case circuit breaker, a 3-pole contractor, and 3 overload relays. Molded case feeder breakers, single and three-phase, are provided for protection of feeders for lighting panels, electric heaters, and other equipment. The Bradley Lake is to be designed as an unattended plant, normally operated from a remote location. However, complete control facilities are also provided for local operation at the plant. Remote control and 7-59 indication is via a microwave communication system. A supervisory, control and data acquisition system (SCADA) is provided to furnish plant control and receive plant operational data at the remote location. The SCADA system is a computer-based system located at a dispatch center, and consisting a remote of a master control unit terminal station. In addition, a second remote terminal unit unit at the power is located at the reservoir gate house to start the propane generator and remotely operate the gate and receive gate position and reservoir level data. Local control consists of vertical, duplex panels, with control and indication on one side, and protective relaying equipment on the other. Direct current power for control, relaying and emergency power and lighting is provided by a 125 volt, 60-cell, 200 amp-hr storage battery and battery charger. A separate 48-volt and uninterruptible power supply (UPS) is provided by the SCADA, microwave, and other critical electrical equipment power requirements. The batteries are located in a separate and well ventilated room, which includes an emergency eyewash sta~ion. The UPS and battery charger is located outside the battery room. The plant telephone system consists of an initial quantity of 12 telephones located throughout the plant, with provision for an additional 4 telephones. Included are connection to three outside lines, with provision for the addition of three lines, and plant paging. The telephone system is designed to operate from 120 V .A. C. 60 HZ, power and will be completely automatic. The off-site communication consists of a microwave system. This system will provide channels for remote control of the Bradley Lake plant from a dispatch center to be determined later, and also for telephone communications. The microwave system is designed to transmit data voice, and control information between the Bradley Lake power plant and Homer which is the nearest point in the communication system of the Bradley Lake plant that is controlled from a point in Anchorage. Communication between Homer and Anchorage will be via existing systems. Microwave is also used to provide control communication and data collection between the powerhouse and the reservoir dam. Where line-of-sight between two points in the system is not available, a passive "billboard" reflector is provided. 7-60 A diesel driven generator is provided in the power plant to supply a station service power under emergency conditions. The generator is rated 250 KW, 480V, three-phase, 60 HZ. It is installed in a separate diesel generator room in the powerhouse. Provisions include air in-take, diesel engine exhaust, a day fuel tank, and a large fuel storage tank. Control features are provided to start the diesel engine and automatically connect it to the station service system, in the event normal station service power is lost. Other features include a 12 volt battery, cooling equipment, brushless excitation, voltage regulator, and an automatic transfer switch rated 480V, three-phase, 60 HZ, 400 amp. A small propane-fueled engine generator is provided at the gate house and the diversion tunnel control house at the reservoir dam. Each generator is rated 5KW, 240V, single phase, 60 HZ. It is equipped with automatic control, a 12 volt battery, equipment for remote starting and stopping, and a battery charger. The set is operated remotely from the powerhouse. Corrosion protection of steel structures and copper grounding gride in the powerhouse and substation is provided by .cathodic protection equipment. The equ-ipment consists of electronic rectifiers to produce a DC voltage of the required magnitude and polarity, and several sacrificial anodes strategically located. Electrical power is provided to several outlying areas such as the permanent village, the domestic water pump house, and the barge docking facilities. This power is provided to these areas via a wood pole line along the access road. Power is furnished at generator voltage of 13.8 kV, 30, 60 HZ. A pad-mounted transformer rated 300 KVA, 13.8 kV-480V, 30 60 HZ. A pad-mounted transformer rated 300 KVA, 13.8 kV-480V, 30, 60 HZ is installed at the village to provide power to the residences, the storage warehouse and domestic water pump house. In addition, a 300 KW diesel generator set is installed at the village to provide power during emergencies. At 75 KVA, three-phase, 60 HZ, 13.8 KV-480V pad-mounted transformer is located at the barge docking facilities, and energized by the 13.8 KV pole line. 7-61 7 . 5 . 7 Mechanical Equipment The turbine will have an actuator-type governor located in a cabinet mounted on floor elevation 23. The governor actuator air-oil accumulator tanks are located adjacent to the governor cabinets. an oil-pressure, pilot operated distributor valve, The governor will be actuator type with solid-state electrically controlled speed responsive elements. The spherical valves are 5 feet in diameter and hydraulic operated. The valves and operating mechanism are located in the valve pit at elevation 5. The hydraulic power unit and accumulator tanks are located on floor elevation 23. The accumulator tanks are located adjacent to the hydraulic power units and have a reservoir capacity for one close-open-close cycle without recharging. A 115 psig air depression system is provided which will depress the tailwater water level to elevation 6 when there are higher tide water levels. Pressurized air is injected into the turbine chamber via embedded wall jets. An ·air receiver, air dryer and filter, two 40 hp air compressors, and four air accumulator tanks are provided on floor elevation 23. There is also a by-pass air manifold provided, which interconnects with the station air system and the air depression system, yet allows each to be isolated for inspection and maintenance. A 115 psig station air system is provided to supply air tools used for operations and maintenance. Air ports are provided at strategic locations throughout the station. This system includes one 30 hp air compressor and a single air accumulator tank. A 50,000 gallon concrete water tank is provided to serve as the powerhouse source of domestic water for potable, fire and cooling water. The.tank is located on a bench adjacent to the tunnel portal. · Booster pumps are provided at floor elevation 23 to boost water pressure throughout the power station. 7-62 The water treatment and potable water system includes a treatment module, purification equipment, holding tank, water softener, demineralizer, hot water tanks, storage tank, and necessary distribution. This equipment is located on floor elevation 23. Two fire systems , water and C0 2 system are provided. The water system includes two 200 gpm booster pumps located at floor elevation 23 to boost station water pressures throughout the fire piping distribution system. This system utilizes the 50,000 gallon domestic water tanks as the primary source of water, and penstock and tailrace are used as the back-up or secondary source. The co 2 system is confined to the generator in the event of an electrical fire. The system includes two banks of eight to ten high pressure co 2 tanks will control unit and injectors located in the generator cover. The station unwater system consist of two 500 gpm single stage ver:t;:ical :<;<" lift pumps and piping discharging to tailwater. The pumps are connect~d by a <?9,mwon··~manifold wit?-isolation gate and check valves provided to dewater eac,h turbine chamber, and allow one pump to be dismantled f·· : maintenance. The unwatering sump is connected to the dirty water sump by a common line which would allow the dirty water pumps to back-up the station unwatering pumps in the event of pump failure or vise versa. All station dirty water is routed to the station dirty water sump. Two 100 gpm pumps are provi~ed which route dirty water to the oil separator and returns water to the station unwater sump. A 48 feet span, 150/25 ton powerhouse bridge crane is provided. The bridge crane is of conventional arrangement. The crane is used for unit assembly, erection and maintenance. Two 12 feet by 17.5 feet draft tube gates are provided for turbine chamber dewatering. These gates are of conventional design and would weigh approximately 4 tons each. A conventional heating and ventilation system is proposed which would be designed to accommodate the minimum recorded temperature of -20°F. A special ventilator will be provided for the auxiliary diesel generator room. 7-63 A sewage treatment module will be provided in the powerhouse which will be designed for continued plant service and. will discharge treated material into the tailrace. The module would provide primary, secondary and tertiary treatment. 7.5. 8 Geology The proposed powerhouse location is situated on a topographic bench above the Kachemak Bay tidal marsh. This bench is underlain by rock at shallow depth as indicated by exposures along the shoreline bluffs. However, with the exception of the bluff exposures and outcrops along a stream 500 feet to the south, the bedrock is almost completely covered by a veneer of soil. Based on these exposures and previous borings drilled to the south along the stream channel, the powerhouse site appears to be underlain by fractured argillite and lesser amounts of fractured graywacke. A dacite dike also occurs in the area and was seen only at a single exposure observed near alternate Francis unit portal location. A hand-dug test pit was located in the area of the portal for the alternate Francis powerhouse. Shallow bedrock was confirmed at this site below about 1 to 2 feet of overburden material. The dacite bedrock encountered in the test pit is similar to other outcrops of dacite dike rocks observed in the Bradley Lake project area. Although the lateral extent of this material at the powerhouse site is not known, its width should not be expected to be great. Although the rock is typically fractured, it is considered satisfactory as a foundation material for the powerhouse. Higher cut slopes, such as above the power tunnel portal, may require some slope protection to control nuisance-level ravelling. 7.5. 9 Access Permanent access to the powerhouse will be provided by road from the permanent camp, barge bas in, and airport. In the event of emergency a 7-64 helicopter can be landed adjacent to the powerhouse near the powerhouse substation in the lay down area. 7.5.10 Powerhouse Alternatives The Corp of Engineers previously studied a shallow underground powerhouse with an underground penstock and pressure tailrace with surge chamber and an above ground powerhouse with an open rip-rap tailrace. The underground powerhouse was more expensive and was not preferred. Only an above ground powerhouse was considered based upon the previous Corp of Engineers findings. A total of six two-unit powerhouse arrangements were developed; three capacities, 60 MW, 90 MW, and 135 MW for Pelton or France turbine generating equipment. Sketches were prepared for each arrangement in order to accurately depict quantities and form the basis for the preparation of cost estimates and economic analysis. All the powerhouse arrangements were technically feasible but the 90 MW Pelton arrangement was economically preferred. 7-65 7. 6 SUBSTATION AND TRANSMISSION 7.6.1 General Transmission of the. power from the Bradley Lake plant is over two parallel, wood pole, 115 kV lines, about 20 miles long. These lines will tap into a new transmission line to be built by Homer Electric Association between Fritz Creek and Soldotna. The powerhouse substation is located adjacent to the powerhouse, as close as possible to minimize the bus connection between the generators and the step-up transformers. Because of the wide range in power plant outputs studied, it was deemed prudent to perform a transmission line analysis to determine a suitable line voltage. The voltage selected is 115 kV. 7.6.2 Transmission Line Analysis The Bradley Lake plant represents a substantial addition to the generating capability of the Kenai Peninsula. The existing transmission system in this area has already reached its maximum capacity without the addition of Bradley Lake. Therefore, it became imperative to perform a transmission line analysis to determine transmission requirements when Bradley Lake becomes operational. SWEC performed this study and details of findings are given in Appendix C of this report. A similar study was made previously by the Alaska Power Administration and is included in the COE General Design Memorandum No. 2 for Bradley Lake. The purpose of the present study is to determine the suitable operating voltage for the transmission lines from Bradley Lake and to determine if the existing transmission line system will be capable of economically transmitting the additional power generated by Bradley Lake. As a result of the analysis the following conclusions have been reached: 0 Two parallel 115 KV, 3-phase, full reliably transmit the power from peninsula transmission system. 7-66 capacity lines are required to the Bradley Lake plant to the o For Bradley Lake plant outputs up to and including 90 MW, a second transmission line between Anchorage and Soldotna is not required. o For Bradley Lake plant output of 135 MW, a second transmission line, preferably rated 230 KV, is required between Anchorage and Soldotna. For maximum reliability, this transmission line should be installed over a different route than the existing Anchorage to Soldotna line. A suggested route would be similar to the existing gas pipeline route, with a submarine cable crossing Turnagain Arm, at the east end of Chickaloon Bay. The requirement for a second transmission line between the above two points is based on a substantial portion of the power from Bradley Lake being exported to Anchorage on a normal basis. o By the year 1995, a new switchyard will be required at Kasilof to tie the two Diamond Ridge-to-Soldotna lines together. This will "stiffen" up the system and increase its transmission capability. The Anchorage/Kenai Peninsuia transmission systems were modeled on a computer. The computer program·used for this purpose is the Electric Power Research Institute (EPRI) Transient Midterm Stability Program. Updated transmission line data was introduced into the computer representing about 25 buses on the Kenai Peninsula. The Anchorage area was represented .• as a single bus. Included were all generating facilities in Anchorage and the Kenai Peninsula areas. Peak load flows for the years 1983 to 2003 were determined using data developed for the Alaska Power Authority, by Harza-Ebasco in July 1983. Several load flow cases were simulated on the computer to determine their effect on the lines, such as losses and voltage levels. Most of the load flows were for the 135 MW plant, during the year 1988. Some 135 MW plant load flows were simulated for the years 1995 and 2003. The effects on the system, stability, losses and bus voltages were determined by simulating several different transmission line outages. The peak load forecasts for the years 1983 to 2003 were obtained from the Harza-Ebasco Susitna FERC License Application dated July 1983. The load forecasts were based on the "Sherman H. Clark Association NSD Case", which listed the Anchorage Area peak load forecasts for each year. Based on 7-67 historical data, it was determined that the Kenai Peninsula loads were approximately 15% of the Anchorage area loads. This value was used for the load flow studies. For individual bus loads within the Kenai Peninsula transmission ·system, Exhibit A1 of the "Feasibility Study of the Soldotna-Fritz Creek Transmission Line", June 1983 by Gilbert/Commonwealth was used. Individual bus loads were assumed to increase uniformly at the same rate as the overall Kenai forecasted loads. The results and conclusions of the load flow studies are based on the following assumptions: (1) The present transmission system will be expanded to include a new 115 kV line from Fritz Creek to Soldotna prior to commercial operation of the Bradley Lake Plant. (2) Existing generating capacity at Bernice Lake is 70 MW and is 15 MW at Cooper Lake. No other generation, other than Bradley Lake will be installed through the year 2003. (3) Acceptable line losses are 10% and acceptable bus voltages are 90% of rated. (4) Bernice Lake will not normally generate power after Bradley Lake is built, but will provide reserve power for emergencies. A power flow diagram was developed for each load flow case. These are shown in the detailed report of the Transmission Line Analysis found in Appendix C. 7.6.3 Powerhouse Substation The substation, shown by Plate 15, is designed in a unitized arrangement. Each generator is connected to a separate step-up transformer, which in turn is connected to a line circuit breaker, then to a transmission line. In addition, the substation contains voltage transformers to measure line voltages, vertical break disconnecting switches and the transmission line 7-68 steel termination towers. The power transformers are furnished with water spray fire protection and oil spill collection systems. A tie circuit breaker is connected between the two 115 kV circuits. This breaker is normally closed to allow power in the Soldotna-Fritz Creek transmission line to flow through the Bradley Lake substation. The substation is designed to transmit the full output of the plant with the loss or removal of one of the two line circuit breakers. Conventional outdoor equipment is utilized in the substation. The power transformers are oil-immersed, tripled rated, OA/FA/FA-33. 8/45/56.3 MVA, three-phase, 60 HZ, HV 115 kV grounded wye, LV 13.8 kV delta. Winding rise is 65°C above an average ambient of 30°C. The circuit breakers are oil immersed, 121 kV class, 3-pole 1200 amp. continuous, 40,000 amp. interrupting. The disconnecting switches are 115 kV, 3 pole, 1200 amp continuous, manually operated, with grounding switches. There are six single phase coupling capacitor voltage transformers rated 115 kV to 115 volts, with dual secondaries. Because of the close proximity of the substation to a body of salt water, all outdoor equipment bushings and substation insulators are extra creep design. A copper ground grid is embedded in the substation which is connected to the substation steel work, the steel fencing, and to the powerhouse grounding system. The surface of the substation consists of crushed rock. 7.6.4 Transmission Lines The transmission facilities for the Bradley Lake project consist of two parallel 115 kV three-phase lines. The proposed routing of the lines is shown on Plate 2. The lines originate at the powerhouse substation and terminate at a location called Bradley Junction, where the two lines tap into a new line to be built by Homer Electric Association (HEA) between Fritz Creek and Soldotna. This new (HEA) line will be in place before the . Bradley Lake plant becomes operational. The feasibility study relating to the transmission line systems associated with the Bradley Lake development was prepared by the firm of . Dryden and LaRue and is contained in this report as Appendix D. The selection of the line routing was based, in general, on the COE original routing, with some minor changes. These changes are the result of 7-69 some geological investigations and determinations of private land ownership. The selected routing avoids the southern boundary of the Kenai National Moose Range, and minimizes private property crossings. In addition, the selected route minimizes the visual impacts of the line and its right-of-way clearing. The selected routing also avoids soft muskeg, swamp and mud areas where line maintenance would be difficult. The design of the lines is based on National Electric Safety Code, grade "B" construction, and· the Design Manual for High Voltage Transmission Lines, REA Bulletin 62-1, revised August 1980. The structures consist of single circuit H-frame wood poles, as shown in Plate 15. The poles are 80 feet long, with embedment from 10 to 14 feet, depending on the soil conditions. The average span between structures is 1000 feet. The selected conductor is 556.5 KCM, ACSR, code name "Dove". The two lines from the plant connect into the Homer Electric Association Fritz Creek line to Soldotna, at Bradley Junction. At this location, there are three independent, manually operated disconnecting switches. The switches will normally be set so that all power in the Fritz Creek/Soldotna line will flow through the Bradley Lake powerhouse substation. In an emergency, the switches at Bradley Junction can be operated to isolate the Bradley Lake plant lines and close the gap in the Fritz Creek/Soldotna line to allow power in that line to bypass the Bradley lake plant substation. The COE envisioned electrically operated load break switches, remotely operated, at Bradley Junction. Because of its remote location, this design would be difficult to accomplish. A source of power would be needed to operate the switches, communication and control equipment. The need for remote control of the equipment at Bradley Junction can be investigated further at a later date. Due to the inaccessibility of a large portion of the transmission lines to normally utilized maintenance vehicles, maintenance costs for the lines will be relatively higher than that for other, more accessible lines. Much of the equipment required for line maintenance will be used only for emergency repairs, and will be used rarely for normal operations. Roads 7-70 are not practical and environmentally not desirable or even allowed. The line will be patrolled and even repaired by helicopter. All terrain vehicles CATV's) will be used to maintain parts of the line, using the right-of-way for access. The structures are designed to be installed and maintained by helicopter. Storage space is provided at the Bradley lake plant for various items of line maintenance equipment and supplies. The recommended transmission line right-of-way and clearing limits have been determined on the basis of the following: o Construction of two, 115 kV, 3-phase transmission lines simultaneously and side-by-side. o Minimum width necessary to maintain proper clearance between lines and to the edge of the clearing due to high winds and falling line structures. o Minimum width necessary to allow clear cutting removal of all major foliage directly under the line and within limits that might threaten line interference in the future. 0 Minimum width necessary to allow selective cutting of timber adjacent to the line to eliminate danger trees across the power lines or structures. the tallest from falling o Minimum width necessary to provide favorable blending of the right-of-way with natural surrounding environment. This determination indicates a clear cutting width of 225 feet along the right of way. To prevent 100 foot high trees from interfering with the line, a selective cutting width of 325 feet will be required. Only the tallest danger trees will be selectively cut in this additional area beyond the clear cut right-of-way. 7-71 7.6.5 Kenai Peninsula-Anchorage Transmission Line Two transmission line routes are investigated that would connect the Kenai Peninsula to Anchorage. These investigations were for the purpose of developing costs for use in the economic evaluation studies. One route follows the existing 115 kV line and the second route examined a line that follows the existing gas line to Chickaloon Bay and crosses Turnagain Arm with submarine cable. The study efforts and findings for this transmission line are given in Appendix D of this report. 7.6.6 Alternatives An alternative 115 kV substation consisting of gas insulated equipment, utilizing sulphur hexafluoride (SF6) gas under pressure as the insulating medium was also investigated. See Figure 7. 6-1. The entire equipment for this substation is installed in a weather proof enclosures at the factory and shipped to the jobsite as a modular unit. The complete module is approximately 15 feet wide by 30 feet long by 12 feet high, and the weight I including all equipment, is about 25 to 30 tons. Outdoor installation of the gas insulated equipment was investigated. However, because of the adverse effect on the gas insulating medium by low temperatures expected at the project location, it was decided to utilize an enclosed substation. The gas insulated substation (GIS) arrangement is more costly initially over a substation utilizing conventional equipment. However, the GIS substation requires only a fraction of the space needed by the conventional equipment and can be installed with a minimum of time and on-site labor. In addition, the modular GIS substation can be completely checked and tested in the factory, thus minimizing field testing and delay during initial plant operation. The enclosed substation protects the HV equipment from the elements and reduces the cost of maintenance. The substation equipment includes a line breaker for each line, and a tie breaker connected between each line. Each breaker is equipped with disconnecting switches to isolate the breakers during maintenance and repair. Included are current and potential trans formers to measure line currents and bus voltages. The tie breaker is normally closed to allow power in the Soldotna-Fritz Creek transmission line to flow through the Bradley Lake 7-72 substation. The substation is designed to transmit the full output of the plant with either the loss of or removal of one of the two line circuit breakers. A copper ground grid is embedded in the substation surrounding the power transformers and the substation module. This grid is connected to the substation steel work, all equipment enclosures, and to the powerhouse grounding system. Connection of the 115 kV GIS equipment to the power transformers is through a GIS bus passing through the substation module wall, and the use of SF6-oil transformer bushings. The 115 kV power is brought out of the substation module via SF6-to-air insulating bushings which are connected to the overhead transmission lines. The modular substation includes all controls for the breakers and motor-operated switches, wired and tested for proper operation in the factory. control cabinets are installed inside the module. These Alternative types of transmission lines from the Bradley Lake project to the Homer Electric Association line were not investigated during ... this ';..~' study. However, buried and submarine cable alternatives were considered by the COE. These alternatives were dismissed by the COE as being too costly or impractical. 7-73 7. 7 CONSTRUCTION FACILITIES 7. 7. 1 General The recommended project requires the development of facilities for access to and within the project area during construction. Also, facilities for housing of personnel and for storage of construction and operational equipment are provided. Whenever possible, facilities required during construction will be so located and designed that they may be used as permanent facilities to serve the long term needs of the project. Facilities not needed for long term project use will be removed and the affected grounds reasonably restored to allow for the reestablishment of natural conditions. Permanent access facilities have been identified and are discussed in Section 7.1 of this report. Essentially all constructio1_1 facilities will be developed under the first construction contract and will include: development o.f staging areas and camp sites; domestic water supply and sewage disposal and/or treatment plant; housing for permanent plant operations personnel and construction manager and engineering support staffs; field laboratory testing, warehousing, and garaging structures. Also to be provided under the first construction contract are the essential services to these facilities including heating, water, sanitary disposal systems, and electricity. The key facilities and services to be provided are described in greater detail in the following paragraphs. 7. 7. 2 Staging Areas Two staging areas approximately 150 are planned feet by 350 development of the barge bas in for feet the is project. A small staging area being provided access way. The area is as part of the located at the terminus of the barge basin and will serve as a temporary laydown area for off loading personnel, equipment, and supplies needed for project development. This area will become the permanent staging area of the project after completion of construction. 7-74 The second and main staging area for construction needs is to be located at the south side of Sheep Point. This area is presently sized as 600 feet by 1, 000 feet. However, further study of construction and scheduling needs for equipment and material should result in a reduction to the staging area requirements. This area will serve as laydown and storage area for each of the contractors on the project and for the construction manager's needs in storing of equipment and supplies. Temporary warehousing and garaging facilities as well as diesel electric power facilities and fuel needs will be located here. In addition, the laboratory testing facilities could be located in this area. 7 . 7 . 3 Camp Areas Two camps of modular construction are proposed for the project. The two-camp concept locates the work force closer to the area ~f construction activity. Approximately half of the work force will be working on the dam, ';;; upper tunnel work, upper access roads, the Middle Fork diversion, and upper reservoir area. The other half would b~ working on construction efforts closer to the lower camp, such a lower access road construction, the power tunnel, the pov1erhouse, and the transmission line. The main advantages of splitting the camps are safety of personnel, shorter travel time, increased job accessibility, and better production and efficiency for the construction efforts, particularly during inclement weather. The disadvantages are additional costs, duplication of utilities, and the early establishment of the upper camp site before access roads are built. The evaluation and studies for the camp sites are discussed in greater detail in Appendix B. Reconnaissance and map interpretation have identified an acceptable location for the lower camp site and a suitable location for the upper camp site. The lower camp area reviewed was that previously identified by the COE in Design Memorandum No. 3. The camp area is located within the floodplain of Battle Creek, approximately 1, 000 feet southeast of the main staging area and near the proposed access road serving the upper dam site. Unvegetated overflow channels are found throughout the east end of the camp area; however, soil borings show excellent foundation material. The positive 7-75 aspects of proximity floodplain. the site, the foundation conditions, flatness, size, and to the work area offset the fact that site is within the This negative aspect is further offset with the location and properly design road section that acts to protect the site from floods. This site is planned for development to accommodate about 240 beds. Suitable housing and recreational facilities will be provided for the crafts. In addition, office and housing facilities are being provided for the needs of contractor's management staff and for staff personnel of the Construction Manager and Engineering Support Services. Messing facilities are being provided to accommodate all personnel using the camp site, including Owner's personnel housed elsewhere. All of the lower camp site facilities can be mobilized by landing craft or barge, then skidded in with a cat or driven in by truck. Several locations were investigated near the dam for a suitable upper camp site. The only suitable site located is about 1. 2 miles due west of the dam near the proposed access road. The site has 4.6 acres of land under 20 percent slope, an apparent water supply, and an area for a sewage lagoon that drains away from the water supply. However, shallow soil conditions present some problems in site development and it is likely that sanitary effluents will need to be trucked to the lower site facilities for disposal. Also, because of difficult early accessibility to the site area, all mobilization must be by helicopter for site development and early use, until the access road is completed. The upper camp site is planned for up to 210 bed capacity. The camp will serve also construction and management staff activities associated with work in the dam area, within the reservoir, and most likely for work on the Middle Fork diversion. Offices, recreational, and messing facilities are provided. As previously stated, office and messing facilities for Owner's personnel are provided at each camp area, as appropriate. However, it is planned to use the permanent plant housing accommodations as sleeping quarters for Owner's personnel. In addition, a project liaison office will be established in Homer to serve the needs of the Owner and its Construction Manager. Permanent plant warehousing, garaging, and other facilities will 7-76 be installed under the first construction contract for early use by the Owner and its Construction Manager. 7. 7.4 Borrow and Waste Area Access Access roads to borrow areas will be either by fill embankment sections or grade cut-fill sections. One major access road has been identified for the project. This is a 1.4 mile road for borrow from the Martin River Delta area. The road alignment previously identified by the COE was reviewed and was determined to be reasonable and used under this study. The road will begin near the lower camp and extend in a westernly alignment to borrow areas at the Martin River Delta. This is considered a temporary access road and will be removed and the surrounding terrain rehabilitated. Its development would consist of essentially leveling and grading the terrain of alluvial fans at about a grade contour of elevation 12 feet. Because of its temporary nature no rip rap protection or gravel top course are provided in its construction. A bridge crossing is required at Battle Creek. That portion of the access road requiring fill/borrow has been assumed as a one lane road. The graded portions of the road are developed as a two lane travelway. Other borrow access roads identified are those relating to the rock quarrying operations for the rockfill dam. These roads are essentially in rock cut and become part of the quarry operations. The roads are within the reservoir area and will be essentially inundated by the increased reservoir height. Waste areas will be located as close as possible to the work so as to minimize their impact and the need for access roads. 7. 7.5 Construction at Dam Site The preferred plan places the dam and other adjacent project structures within the compact river channel area near the outlet of Bradley Lake. This consolidates construction activities within a small area. The major construction efforts at the dam site are: the dam and its spillway; the 7-77 diversion tunnel; the power tunnel intake channel and intake structure; and the gate structure and adjacent tunnel and inclined shaft. Construction facilities at the dam site will consist of office trailers, a small concrete hatching plant, and the short roads needed to access the various construction activities. Construction activities and access roads relating to the placement of dam fill material, the concrete facing, the intake channel and intake structure, and the power tunnel work will all be located within the reservoir and eventually these structures will be under water when the reservoir is raised. The construction access road, placed downstream of the dam and used to develop the diversion tunnel, will be refurbished and used as a permanent access to this structure. The gate shaft is located near the main access road for the dam and requires only little additional work for its development. Similarly, bridging of Bradley River, needed for the construction of the diversion tunnel, would be removed prior to constructing the dam. 7.7.6 Construction.at Powerhouse Under the preferred plan the excavations required for the power tunnel portal and the powerhouse are combined into one single excavation. Excavated material is placed in the tidal flats adjacent to the shore to create laydown and work areas for construction, including an area for onsite office trailers and the diesel generating equipment needed for powering the tunnel boring machine and for lighting this area. After construction these laydown areas would serve the permanent plant. One area will be used for development of the plant substation and the other will form an access area for plant maintenance needs. 7. 7. 7 Water Supply The first construction contractor will be required to develop the water system for the project needs. The water supply for domestic water will be designed to provide the domestic flow demand of the construction camp or the fire flow demand, whichever is greater. For the lower camp, the water supply will be from surface runoff or underground sources. Water treatment 7-78 facilities will be provided to assure good quality and safe potable water. It is anticipated that ground water treatment will consist only of chlorination; however, surface water may require more extensive treatment, including sedimentation and filtering. It is more likely that wells will be developed for the water supply. The water system for construction needs will be designed so that it can also serve the long term needs of the permanent plant. Water for construction will be similarly collected and treated only to the extent required for good concrete development. Domestic water sources will be developed in full compliance with applicable regulations. Domestic water needs for the upper camp will be from the lake adjacent to the camp or other nearby lakes. The water supply will be sized to provide either the domestic needs of the camp or fire fighting needs, whichever is greater. It is anticipated that the water treatment will be by filtration and chlorination. It is doubtful that a ground water source can be developed for the upper camp area. Water for construction will be from Bradley Lake. Some treatment by filtering may be required to remove suspended material. 7. 7. 8 Sewage Disposal The first construction contractor will be. required to develop the sewage collection system and connect it to the appropriate facilities. Waste water will be placed in an aerated sewage lagoon. Effluent will be discharged into Battle Creek or some other point acceptable to the controlling agency. Because it is likely that suitable sewage treatment facilities cannot be developed at the upper camp site, it is planned to provide a series of holding tanks to retain waste material. The waste material will be trucked to the lower camp sewage facilities for treatment and disposal. Additional field investigations are needed to better define sewage handling for the upper camp. 7-79 7.7.9 Electric Power Electric power for construction and domestic needs will be under the responsibility of the first construction contractor. This contractor will be the first on site, will require the greatest· amount of electrical energy and will be responsible for the establishment and operation of all camp facilities. It is anticipated that about 5 to 6 MW of capacity will be needed at the lower construction area. Of this, 2 to 3 MW will be required by the tunnel boring machine, about 1 MW for the lower camp and miscellaneous housing, warehouse and garaging facilities, and about 1 MW for lighting of the main storage and construction areas. Additional diesel generated power will need to be provided at the upper camp and construction area. It is anticipated that about 2 MW of capacity will be needed to serve these facilities. Adequate fuel supply and reserves will be provided to allow for 2 weeks of operation without refueling. Fuel storage will be developed in full compliance of State and Federal requirements. 7.7.10 Other Facilities Facilities for storage of explosives will be provided at appropriate and safe locations in full compliance with State and Federal requirements. 7-80 7. 8 BUILDINGS, GROUNDS AND UTILITIES 7.8.1 General The remote Bradley Lake Project site will have air or waterborne access only. The plant will be computer controlled and remotely dispatched via a microwave link. A resident staff will be required to perform daily operation functions and routine maintenance. The project site is relatively close to Homer, but because of limited access, onsite facilities and operations equipment must be provided to perform all necessary maintenance and repair. The permanent buildings, grounds and utilities required are located near the lower construction camp adjacent to Battle Creek. Family residences are provided for each of the permanent onsite personnel. In addition, a twelve man bunkhouse with kitchen facilities is provided in the event more personnel are required onsite during periods of major maintenance. 7. 8. 2 Staffing The permanent resident staff will consist of a plant supervisor and three maintenance-operators. Additional maintenance personnel would be assigned to the site during periods of major maintenance on a temporary basis. Dispatching will be performed remotely by the operating utility. Since the area utilities presently have 24 hour dispatch coverage, no additional dispatch personnel are required. 7. 8. 3 Maintenance Facilities The following maintenance facilities are provided: o 10,000 square feet warehouse and machine shop o Outside fenced-in storage area o Outside fenced-in parking area for operations equipment o Fuel storage -underground tanks for gas and diesel fuel 7-81 One of the construction warehouses will be left in place as part of the permanent building facilities. This warehouse will be remodeled to include 4000 square feet of bin and rack storage, 2000 square feet for the machine shop, and the remaining floor area will be open for laydown work and vehicle maintenance. Additional tool and small part storage is provided on the generator floor of the powerhouse. Designated outside fenced-in parking and storage areas are provided. A 6000 square feet fenced-in gravel surfaced area is provided adjacent to the warehouse, to park the operations equipment. Outlets for resistance heaters would be provided at each parking space. A 6000 square feet fenced-in gravel surfaced storage area is provided also adjacent to the warehouse. Bulk outdoor storage racks are provided for material storage. Fuel storage will utilize underground tanks of 10,000 gallon capacity, one each for gasoline and diesel fuel. 7. 8. 4 Operations Equipment A comprehensive list of operating equipment was made available to the Alaska Power Authority. Included are heavy road and building maintenance equipment, machine shop equipment and maintenance equipment for each project structure. The capital cost of this equipment is included in the project cost estimate and a sinking fund is included in the annual operations and maintenance budget estimate for future equipment replacement. 7.8.5 Residential and Office Facilities The residential facilities are as follows: 3 -three bedroom houses (permanent personnel quarters) 1 -four bedroom house (supervisors quarters) 1 -twelve bed bunkhouse with kitchen facilities (temporary personnel quarters) The permanent houses will be architecturally blended into the timber adjacent to the lower construction camp site and above the flood plain. 7-82 Each residence will be separated from each other and the warehouse, bunkhouse and other permanent camp facilities, to permit some seclusion and privacy. The office facilities are part of the control room in the powerhouse. A small office and conference room will be included in the bunkhouse. Due to the site's isolation, facilities will be incorporated into the permanent residences for long term subsistence. Fireplaces and wood stoves would also be provided for back-up heating. A stand-by diesel generator is provided in the event of power loss. Telephone communication will be provided via microwave link. 7 .8.6 Water Surface or well water resources can be developed to provide domestic water for the construction camps and permanent camp. To be conservative, water treatment facilities are based on a surface water source. Well water would simply require chlorination. The domestic water would be furnished as part of the contract which develops the construction camps. Each residence, bunkhouse and warehouse has a 200 gallon capacity domestic water storage tank. A separate domestic water system is provided at the powerhouse including extensive treatment facilities. The powerhouse domestic water is also used for generator equipment cooling. Drinking water at the dam, intake gate shaft, and other locations will be transported with personnel. 7. 8. 7 Wastewater Treatment and Disposal Aerated lagoons are provided for the lower construction camp, but may be too far removed from the permanent camp facilities to be retained. A conventional septic tank and drain field is therefore provided for each permanent residence, bunkhouse, and warehouse. Effluent will be transported from the upper construction camp to the lower construction camp facilities for treatment. The powerhouse has a self-contained sewage treatment module. The treatment and disposal method will comply with applicable Federal and State standards, and the applicable permits will be obtained. Portable toilets will be used at other site locations. 7-83 7. 8. 8 Fire Protection Each structure will be furnished with a minimum of two means of egress. Emergency lighting and smoke alarms will be provided in each structure. Fire water will be provided by the domestic water system supplemented by surface water at the permanent camp. The powerhouse has two fire protection systems, one water and the other carbon dioxide. Hand fire extinguishers are provided in each building. 7.8.9 Project Physical Security Vandalism and theft after construction are not anticipated due to the remoteness of the project site. However, steel doors with dead bolt security locks will be provided for the exterior doors of all project structures. Chain link fencing with two top barb wires will surround the powerhouse substation and designated project storage areas. these fenced areas will be through locked gates. 7. 8.10 Solid Waste Facilities Access into Solid waste disposal will be in accordance with applicable Federal and State requirements. Several methods of disposal are under consideration, including incineration, local sanitary land fill operated by project personnel, and containerization and transportation of solid waste to a suitable disposal site. The local sanitary land fill operated by project personnel may be the most economical but additional study is required. All necessary permits will be obtained. 7 .8.11 Other Facilities Site Power will be provided by the station service facilities at the powerhouse. Standby diesel generators are provided at the permanent building area and powerhouse for emergency and start-up power. Small propane generators and batteries are provided at the intake gate shaft and diversion gate house for power. 7-84 7. 9 MIDDLE FORK DIVERSION 7 . 9. 1 General The Middle Fork Diversion is located approximately one mile north of Bradley Lake in an adjacent drainage at elevation 2,200 on the Middle Fork stream. The Middle Fork Diversion facilities consist of a small dam, spillway, and two diversion lines. One line is provided for initial construction efforts to bypass natural streamflows, and subsequently to serve as a permanent outlet for downstream releases. The other main diversion line conveys water to Marmot Creek, a tributary to Bradley Lake. The interbasin diversion facility which will be operational· from May through October, provides additional water to the Bradley Lake reservoir and increases the energy benefits for the project approximately 1,000 KWHR for every acre-foot diverted. 7. 9. 2 Recommended Plan The recommended plan for developing the Middle Fork Diversion is a small 20 foot high rockfill dam with a sheet pile cut-off wall and an excavated channel spillway in the right abutment. The main diversion line and low level outlet intake works are integral with the dam. The low level outlet serves as a temporary diversion during construction of the dam, spillway, and main diversion flow line intake. Both the main diversion line and low level outlet are 6 foot diameter steel pipes with face mounted manually operated intake sluice gates. The main diversion line is approximately 1, 900 feet long and is buried along its entire length with a slope of 0.6 percent. The terrain along the proposed alignment is typically exposed bedrock, and "drill and shoot" excavation techniques are required. The pipeline bedding and cover material is shot rock from the excavation. The low level outlet is located. in an excavated rock trench on the left bank. The low level outlet pipe invert is located approximately 3 feet below the natural stream channel bottom elevation to permit streamflow 7-85 diversion during the dam and spillway construction and allow the reservoir to be lowered for intake sluice gate inspection. It also serves as a permanent outlet for downstream releases during the November through April period. The intake for the main diversion line and the low level outlet is a reinforced concrete structure with a platform for the manual operators at elevation 2,212. The intake works encases the 6 foot diameter pipes and provides anchorage for the intake sluice gates and operators. The spillway is a 30 feet wide channel located in the right abutment. The material excavated for the spillway will be used for the dam rockfill. A 30 feet wide, 4 feet high concrete wier with crest at elevation 2, 204 is located in the spillway channel at the dam axis. The spillway channel is excavated in bedrock and is not lined. The Middle Fork Diversion concept is shown on Plates 16 and 17. 7 .9.3 Geology The bedrock in the area between the Middle Fork Diversion and Marmot Creek is predominantly graywacke with argillite interbeds. Much of the proposed route is covered with talus and muskeg swamps, which prevented a detailed assessment of geologic conditions. Overburden depths vary from less than 1 foot to over 15 feet as determined by seismic refraction surveys by others. Gravel and/or sand footings may be required for diversion pipe supports. For such support systems, the bedrock structure should not present any stability problems. This information is derived from COE data; the scope of this current study did not include further investigation of this area. 7 . 9. 4 Technical Details The hydraulic rating curves for the spillway and main diversion line are shown on Figure 7. 9-1. The main diversion line can pass 450 cfs into Marmot Creek without spillway discharges occurring at the diversion dam. The spillway can pass about 1,600 cfs at pool elevation 2,210 which exceeds 7-86 the 100 year design flood discharge with no flow in the main diversion line and 2 feet of freeboard on the dam crest. The main diversion line can pass an additional 6 70 cfs if operational with the pool at elevation 2, 210. Should streamflows exceed 1,600 cfs (or 2,300 cfs if the line is operational), the water level will continue to rise until the dam is overtopped at pool elevation 2,212 which corresponds to a spillway flow of 2, 600 cfs. The combined capacity of the spillway and main diversion pipe at pool elevation 2, 212 is approximately 3, 400 cfs. This represents about 85 percent of the PMF peak flow as determined by the COE. Should the diversion dam be overtopped little damage is anticipated to either the dam, flow lines, or the downstream river section, and it is not justified to design the structures for larger and more improbable design flows. The main diversion line and low level outlet will be vented downstream of the intake sluice gates. Field observations indicate streambeds are cut into rock. that the Middle Fork and Marmot Creek The spillway channel is excavated in rock and directs discharges into the natural streambed downstream of the dam toe. The low level outlet discharges water onto a concrete apron and into the natural streambed also downstream of the dam toe. The COE expected some limited erosion of the tundra and soil cover below the outlet of the main diversion line. This appears reasonable based on field observations in this locale and the Marmot Creek streambed. The COE field observations indicated that snow remained in the diversion area well into August but that snow slide areas were not evident. SWEC concurs with the COE that a buried pipeline is the most reliable means to convey diverted waters to the Bradley Reservoir during the May to October period. Snow is likely to drift and pack itself against an exposed pipeline resulting in large external loads from snow creep. Technically the buried pipeline offers the best solution. Operating the main diversion line from May to October will limit ice formation in the diversion pipeline or low level outlet. The reinforced 7-87 concrete intake structure, rockfill dam, and reinforced concrete spillway weir offer suitable ice resistance. 7.9.5 Dam, Gates, and Conduit The rockfill dam will be approximately 140 feet long and 20 feet high with a central sheet pile cut off wall embedded in a rock key. along the dam axis. A 15 feet deep grout curtain seals the foundation rock below the concrete key. The 6 feet diameter diversion pipes are encased in reinforced concrete at the rock key and the sheet pile is embedded in the encasement. At each end of the dam the sheet pile is embedded in concrete keyed into the abutment rock. The concrete spillway weir, 4 feet high . and 30 feet long, is also keyed into the foundation rock, and the 15 feet deep grout curtain along the dam axis is continued under the weir and into the right abutment. The spillway weir crest is 8 feet below the top of the dam. The main diversion line consists of a common intake structure with the low · level outlet) a 6 feet entrance sluice gate with manual operator, a 1,900 feet long, 6 feet diameter, 3/8 inch thick steel pipe buried throughout its length to preclude snow creep damage, and a screened outlet. The low level outlet consists of a intake structure common with the main diversion line, a 6 feet entrance sluice gate with a manual operator, a 6 feet diameter 3/8 inch thick steel pipe embedded in the dam, a screened outlet to prevent entry, and a concrete apron downstream of the outlet. 7 .9.6 Access Access to the Middle Fork Diversion during construction will be by helicopter. Sky cranes will be used to transport personnel, material, and construction equipment. Two helicopter trips will be required to the Middle Fork Dam each year for operations and maintenance, one trip in May and one in October. The trip in May will be required to open the Main Diversion flow line sluice gate and close the low level outlet sluice 7-88 gate. The October trip will be required to close the diversion gate and open the low level outlet gate. The COE studies concluded that an access road to the Middle Fork Diversion is not recommended. SWEC concurs with this recommendation, however, remote telemetry to control the sluice gates or monitor Middle Fork flows as recommended by the COE, will impose an additional operations and maintenance expense which is considered unwarranted. 7. 9. 7 Alternatives The COE considered several types of diversion dams and conveyance alternatives. The COE concluded that an uncovered trapezoidal channel would be blocked by snow and ice for parts of the planned operation period between May and October and that it would not be feasible to keep the channel free to pass the required discharge. Also, the COE studied an ·;'5 .• above ground pipel~ne and concluded it would be uneconomical to design the pipe to resist the large forces exerted by the snow cover. The COE concluded that a buried pipeline is the best method for conveyance of diversion flows from the dam to the Bradley Lake drainage basin. SWEC reviewed the various conveyance alternatives and concurs with these conclusions. The COE developed timber dam, concrete dam, and a metal binwall dam alternatives at Middle Fork. SWEC developed two additional alternatives: A concrete faced rockfill and a central sheet-pile cutoff rock fill dam. The rockfill dams utilize rock available at the dam site. Haterial excavated from the spillway is utilized for the dam rock fill. Due to the remoteness of the Middle Fork Dam durability and ability of the dam to resist the elements is of prime importance. A substantial dam, as proposed by SWEC, offers better durability to weather and other severe factors, such as snow and ice that will be present at the site, and is preferred. The central sheet-pile cutoff rockfill dam offers better internal drainage within.the dam, eliminates concrete work, and is technically preferred. 7-89 DESIGN WINDSPEEDS (MPH) AT SHEEP POINT KACHEMAK BAY, ALASKA Exceedance Interval (~ears) Orientation Duration (hours) 2 5 50 210° -260° 1 57 62 68 (summer) 12 47 52 63 300° -30° 1 32 36 47 (winter) 12 21 26 36 (1) After Corps of Engineers, NPS, Design Report Access Channel and Moorage Basin Facilities. '----------TABLE 7 .1-1--.~ DESIGN WAVE CHARACTERISTICS (1 SHEEP POINT AND CHUGACHIK ISLAND SITES KACHEMAK BAY, ALASKA Freguenc~ (~ears2 Wave 2 5 50 Location Origination Hs (ft) T (sec) Hs (ft) T (sec) Hs (ft) T(sec) Sheep 250°AZ 4.4 4.3 4.7 4.5 5.1 Point 270°AZ 3.5 3.8 3.8 3.9 4.1 315°AZ 2.0 2.8 2.4 3.1 2.9 . Chugachik 240°AZ 6.1 5.3 6.7 5.6 7.4 Island 260°AZ. 5.9 5.3 6.5 5.5 7.2 360°AZ 2.2 3.0 2.5 3.2 3.1 (1) After Corps of Engineers, NPS, Design Report Access Channel and Moorage Basin Facilities. (2) H (ft) =wave height s T (sec) = wave period 4. 7 4.1 3.4 5.8 5.7 3.5 ""------------TABLE 7.1-2-----.~ POWER HOUSE CAPACITY (MW) 60 90 135 TYPE OF EVENT Load Acceptance Load Acceptance Load Rejection Load Rejection Load Acceptance Load Acceptance Load Rejection Load Rejection Load Acceptance Load Acceptance Load Rejection Load Rejection HGL = Hydraulic Grade Line SYNCHRONOUS BYPASS BYPASS VALVE SIZE (FT) Valve Closed Valve Closed 2.5 Diameter 65 Sec. Closure 3.0 Diameter 65 Sec. Clos.ure Valve Closed Valve Closed 3.0 Diameter 65 Sec. Closure 3.5 Diameter 65 Sec. Closure Valve Closed Valve Closed 4.0 Diameter 65 Sec. 4.5 Diameter 65 Sec. WICKET GATE CLOSURE TIME (SEC) 5 5 5 5 5 5 HYDRAULIC TRANSIENT ANALYSIS FRANCIS TYPE TURBINES WICKET GATE OPENING TIME (SEC) 10 SURGE TANK DESCRIPTION WATER SURFACE ELEVATION @ SURGE TANK (FT) HGL PT "A" POWERHOUSE (FT) 621 HGL PT "C" END OF STEEL LINER (FT) 827 HGL PT "D" SURGE TANK BELOW ORIFICE 964 HGL PT "E" BOTTOM OF 50° SHAFT (FT) 995 HGL PT "F" TOP OF 50° SHAFT (FT) 1,105 HGL PT "G" HEADWATER LEVEL (FT) 1,081 15 ft. Tank I.D. 5 ft. Orifice 964 (min) ---------------No Water Column Separation 20 10 20 10 20 15 ft. Tank I.D. 5 ft. Orifice 15 ft. Tank I.D. 5 ft. Orifice 15 ft. Tank I.D. 5 ft. Orifice 15 ft. Tank I.D. 5 ft. Orifice 15 ft. Tank I.D. 5 ft. Orifice 15 ft. Tank I.D. 5 ft. Orifice 15 ft. Tank I.D. 5 ft. Orifice 20 ft. Tank I.D. 6 ft. Orifice 20 ft. Tank I.D. 6 ft. Orifice 20 ft. Tank I.D. 6 ft. Orifice 20 ft. Tank I.D. 6 ft. Orifice 963 (min) 1,149 (max) fm<>v) 'I.U"'""'-" 932 (min) 930 (min) 1,149 (max) (max) 924 (min) 922 (min) 1,101 (max) (max) 810 938 967 1,035 1,047 1,081 ---------------No Water Column Separation 1,478 1,425 1,247 1,251 1,222 1,170 No Water Column Separation ------------ 1,284 1,282 No \~ater 544 777 933 976 999 1,081 No Water Column Separation ------------ 754 907 935 . 1,023 1,038 1,081 No Water Column Separation ------------ 1,517 1,449 1,256 1,267 1,231 1,170 No Water Column Separation ------------ l, 318 1, 308 No Water Column Separation ------------ 442 711 924 955 978 1,081 No Water,Column Separation ------------ 675 863 926. 1,010 1,026 1,081 No Water Column Separation ------------ 1,422 l, 383 1,215 1,270 1,232 1,170 No Water Column Separation ------------ 1,223 1,218 No Water Column Separation ------------ ...__ ____________ _.; _____________ TABLE 7.4-1 POWER NEEDLE HOUSE TYPE VALVE CAPACITY OF OPENING (MW) EVENT TIME (SEC) 60 Load 35 Acceptance Load 60 Acceptance Load Rejection 90 Load 35 Acceptance Load 60 Acceptance Load Rejection 135 Load 35 Acceptance Load 60 Acceptance Load Rejection HGL -Hydraulic Grade Line HYDRAULIC TRANSIENT ANALYSIS PELTON TYPE TURBINES HGL NEEDLE HGL PT "C" VALVE PT "A" END OF CI,.OSING POWERHOUSE STEEL LINER TIME (SEC) (FT) (FT) 629 668 (min) -------- 768 803 (min) -------- 60 1,407 1, 379 (max) -------- 543 586 (min) -------- 699 740 (min) -------- 60 1,479 1,443 (max) -------- 437 482 (min) -------- 606 653 (min) -------- 60 1,599 1,547 (max) -------- HGL HGL PT "D" PT "E" HGL BOTTOM OF TOP OF PT "F" 50° SHAFT 50 0 SHAFT HEADWATER (FT) (FT) LEVEL 1,021 1,051 1,081 No Water Column Separation -------- 1,046 1,063 1,081 No Water Column Separation -------- 1,196 1,183 1,170 No Water Column Separation -------- 1,005 1,042 1,081 No Water Column Separation -------- 1,036 1,058 1,081 No Water Column Separation -------- 1,204 1,187 1,170 No Water Column Separation -------- 981 1,030 1,081 No Water Column Separation -------- 1,021 1,051 1,081 No Water Column Separation -------- 1,216 1,193 1,170 No Water Column Separation -------- L------~----------~----------TABLE 7.4-2 ROCK CORE PROPERTIES GREYWACKES, GREYWACKE/ARGILLITE (CATACLASTIC), AND TUFF Rock Type (Or Notes) Sample No. Testing(l) Unit Weight Agency (lb/cu ft) Gywke/Arg Greywacke Greywacke Greywacke Gywke/Arg Greywacke* Greywacke* Greywacke* Gywke/Arg Gywke/Arg Gywke/Arg Greywacke Greywacke Greywacke Greywacke Gywke/Arg Greywacke Gywke/Arg Greywacke* Greywacke* Gywke/Arg Greywacke Greywacke 0.224 0.224 Gywke/Arg Greywacke Greywacke Greywacke S-4 S-5 S-6a S-6b J-2 J-3 J-5 J-6 4-l (2) 5-2 (2) 5-"3 (2 ) 6-2 (2) 6-3 (2) 7-l 7-2 (2 ) 8-10 8-11 9-9 ll-46 12-2 13-31 14-7 16-2 (2 ) 2260 2260 R-4 R-6 R-3 R-1 s s s s J J J J c c c c c c c c c c c c c c c R R R R * Probable Tuff or Tuff/Greywacke (l) S -A. J. Hendron for SWEC C -u. s. Army Corps of Engineers J -Atlas Copco Jarva, Inc. R -The Robbins Co. (2) From Dam Area (3) 0 = Least, 6 = Most Abrasive 171 171 172 174 172.8 170.9 170.9 172.8 173.4 171.6 171.6 172.8 172.2 170.9 173.5 170.9 172.2 170.9 172.2 No Test No Test 168.7 169.0 Unconfined Compressive Total Modulus of Elasticity (Exl06psi) Poissons Ratio (u) Splitting Tensile Strength Point Load (psi) Shore Chercher(3) Strength (psi) Hardness (psi) Hardness Abrasivity 12,763 10,168 32,825 34,975 No Test 10,295 No Test 8990 14,900 10,500 10,000 31,200 35,600 26:600 30,000 33,200 30,900 26,800 20,400 11,500 17,200 29,400 34,100 No Test No Test 12,943 24,413 110.39 108.86 149.84 153.51 Estimated: 10.07 7.22 9.58 11.24 13.80 9.77 10.10 11.14 10.79 10.35 9.45 9.50 10.10 10.43 10.37 0.285 0.375 0.245 0.267 0.355 O_?f-.7 ----· 0.267 0.228 0.249 0.248 0.235 0.265 0.257 0.224 0.224 Tunnel Length Involved -4300 ft Penetration Rate -6-8 ft/hr Delay Time -N/ A 1600 860 No Test 1770 2070 No Test 2400 2320 1950 2820 1650 No Test 1900 2180 2260 10.0 6.1 9.1 8.0 7.9 No Test No Test 8.4 73.4 72.1 73.0 73.1 Temporary Support -Selectively located, 3/4 in. diameter, 3.0 2.0 2.4 3.2 6 ft long, mechanically -anchored rock bolts. Two bolts per 4 lin. ft; 215 bolts total ~------------------------~~--------------~----TABLE Abrasion Hardness 5.1 5.4 - 5.85 6.3 7.4-3 ___, Rock Type Sample Testing(!) Unit Weight (Or Notes) No. Agency (lb/cu ft) S-1 s 171 H-lA s 170.5 H-lB s 169.5 H-2 s 169.4 Moderately H-3 s 169.7 Siliceous V. Weak J-1 J Foliation J-8 J Slightly J-11 J Cherty V. Weak R-9 R 165.5 Fo11iation R-10 R Not Tested Slightly R-7 R Not Tested Cherty (l) S -A. J. Hendron for SWEC C -u. S. Army Corps of Engineers J -Atlas Copco Jarva, Inc. R -The Robbins Co. (2) From Dam Area (3) 0 = Least, 6 = Most Abrasive Unconfined Compressive Strength (psi) 8,266 18,958 19 '718 12,733 25,820 6,670 8,700 Not Tested 15,784 19,993 Not Tested ROCK CORE PROPERTIES MASSIVE ARGILLITE Modulus of Total Elast~city Poissons Hardness (ExlO psi) Ratio (u) 56.73 86.82 85.28 57.40 81.23 ..: Estimated: Tunnel Length Involved -5000 ft Penetration Rate -8-10 ft/hr Delay Time -N/A Splitting Tensile Point Strength Load Shore (psi) (psi) Hardness 38.6 76.4 71.4 74.8 71.7 7.3 10.0 4.8 No Test No Test 5.0 Temporary Support -Selectively located, 3/4 in. diameter, Chercher(3) Abrasivity 2.2 2.4 2.2 6 ft long, mechanically -anchored rock bolts. Two bolts per 4 lin. ft; 250 bolts total Abrasion Hardness 2.16 3.11 2.95 2.06 3.50 ....____-..,..------:----------------~----------TABLE 7.4-4 Rock Type Sample Testing(l) Unit Weight (Or Notes) No. Agency (lb/cu ft) A few Ch-llA s 168 Calcite Veins CH-llB s 168 S2 s 169 9-10 c 169.7 10-13 c 166 Highly J-4 J Cherty 40% J-9 J Argillite 70% J-10 J Argillite Highly R-11 R No Test Cherty 40% R-5 R 162.7 Argillite 70% R-8 R No Test Argillite Chert S-3 s 165 Nodules (No dacite Tested) (l) s -A. J. Hendron for SWEC C -u. s. Army Corps of Engineers J -Atlas Copco Jarva, Inc. R -The Robbins Co. (2) From Dam Area (3) 0 = Least, 6 = Most Abrasive ROCK CORE PROPERTIES FOLIATED ARGILLITE Unconfined Modulus of Compressive Total Elasticity Poissons Strength (psi) Hardness (Exl06psi) Ratio (u) 6,661 92.53 5,038 68.65 FOLIATED, CHERITY ARGILLITE, INCLUDING DACITE 2,943 54.67 12,500 7.20 0.119 9540 4.67 0.265 No Test 3915 No Test No Test 6,945 No Test 4,204 67.28 Estimated: Tunnel Length Involved -Foliated Argillite, Penetration Rate -Foliated Argillite, 10-12 Splitting Tensile Point Strength Load Shore Chercher ( 3) (psi) (psi) Hardness Abrasivity 86.3 69.2 69.2 910 1,180 6.8 4.8 4.0 3.8 4.8 2.2 5.9 3.2 No Test 69.6 3500 ft; Folia ted, :Cherty Argillite, 3790 ft ft/hr; Foliated, Cherty Argillite 8-10 ft/hr Delay Time -N/A Temporary Support -(Both Units) Selectively located, 3/4 in. diameter, 6 ft long, mechanically -anchored rock bolts. Two bolts per 4 ft; 365 bolts total Abrasion Hardness 2.16 2.7i 2.57 4.8 L...-.-------------------------r---TABLE 7.4-5 Rock Type Sample Testing(l) Unit Weight (Or Notes) No. Agency (lb/cu ft) CH-llD s 167 CH-llE s 168 CH.:..llF s 169 CH-llG s No Test CH-11H s 167 CH-lli s 168 J-7 J R-2 R 169.5 (1) S -A. J. Hendron for SWEC C -U. S. Army Corps of Engineers J -Atlas Copco Jarva, Inc. R -The Robbins Co. (2) From Dam Area (3) 0 = Least, 6 =Most Abrasive ROCK CORE PROPERTIES CHERT Unconfined Modulus of Compressive Total Elasticity Poissons (Exl06psi) Strength (psi) Hardness Ratio (u) 11,121 7,570 9,215 No Test 6,897 8,416 No Test 22,729 199.34 181.04 204.41 171.76 185.39 204.33 Estimated: Tunnel Length Involved -50 ft. Penetration Rate -3.0-5.75 ft/hr Delay Time -N/ A Splitting Tensile Point Strength Load (psi) (psi) 8.2 8.4 Temporary Support -Selectively located, 3/4 in. diameter, Shore Ch erch er ( 3) Hardness Abrasivity 98.3 92.0 91.4 91.2 94.4 99.2 4.4 6 ft long, mechanically -anchored rock bolts. Two bolts per 4 ft; 6 bolts total Abrasion Hardness 11.3 9.6 14.5 8.8 11.8 15.5 .___ ____________ __;,.__,;,.=·-~--.. ---------TABLE 7.4-6 ___, Sample Testing(!) Unit Weight Rock Type No. Agency Altered A Station s Quartz 242+71 Diorite B Station s Test 242+11 Fresh A Station s Quartz 241+59 Diorite B Station s 241+59 C Station s 241+59 A1 tered SR-1 s Quartz Station Diorite 224+64 Fresh Hr-1 s Quartz Station Diorite 239+30 HR-2S s Station 239+30 (1) S -A. J. Hendron for SWEC C -u. S. Army Corps of Engineers J -Atlas Copco Jarva, Inc. R -The Robbins Co. · (2) From Dam Area (3) 0 = Least, G = Most Abrasive (4) Not Corrected for L/D 2 (1b/cu ft) No Test 162.22 165.98 164.98 166.11 No Test 165.2 165.1 ROCK CORE PROPERTIES FRESH & ALTERED QUARTZ DIORITE TERROR LAKE TUNNEL Unconfined Average(5) Distance Compressive Total Penetration Penetrated Strength (psi) Hardness Rate( ft/hr) (ft) No Test 106.59 No Data 22,809.1<4 > No Test No Data 22,598.3(4 ) 106.4 7.1 35 22,008.8<4 > 119.31 7.1 35 23,178.4<4 > 121 7.1 35 No Test 74.82 14.2 57 26,055 123.05 8.4 42 22,682 133.27 8.4 42 (5) Average Shift Penetration Rate, Includes Machine Down Time Splitting Tensile Point Chercher(3) Strength Load Shore Abrasion (psi) (psi) Hardness Abrasivity Hardness 43.3 6.06 No Test No 85.26 6.51 88.69 6.64 83.04 7.25 84.8 6.17 94.6 7.94 91.7 7.52 '----------------..;...__----------TABLE 7.4-7 Rock Type and/or Conditions Length (ft) Fault Zones Bull Moose 100 Bradley River 250 Fracture Zones Lineaments 200 Random 200 Gouge/Breccia Bull Moose 15 Bradley River 30 Random 15 Portal, D/S 50 TUNNELING CONDITIONS FAULT & FRACTURE ZONES, PORTAL Penetration Delay Rate ( ft/hr) Hardness Time (days) Temporary Support N/A N/A 5 2/3 Sets, WF 4xl3 N/A N/A 12 2/3 Sets, WF 4xl3 N/A N/A 10 2/3 Sets, WF 4xl3 N/A N/A 10 2/3 Sets, WF 4xl3 N/A N/A 2 Full circle sets, N/A N/A 5 Full circle sets, N/A N/A 2 Full circle sets, WF 5xl9 WF 5xl9 WF 5xl9 Drill & Blast 130 N/A Full sets, WF 4xl3 Remarks Probably primarily fractured, cherty, foliated argillite. He-steel -#8 @ 12 in. each way. Breccia w/Gouge Matrix Gouge Gouge '-----------------~----------TABLE 7.4-8 ___, LIST OF THIN SECTIONS Section No. Coordinates Depth (ft) Classification S-1 N2,103,760 E343,580 11.9 Massive Argillite S-1 N2,103,760 E343,580 18.4 Foliated Cherty Argillite S-3 N2~111,580 E328,110 82.3 Foliated Cherty Argillite S-4 N2,103,760 E343,580 38.0 Mi~ed Graywacke/Argillite S-5 N2,103,760 E343,580 54.0 Graywacke S-6A N2,103,780 E342,760 17.3 Graywacke S-6B N2,103,780 E342,760 19.0 Graywacke M-1 N2,106,720 E366,200 Surface Foliated Cherty Argillite M-2 N2,106,930 E366,200 Surface Tuff M-3 N2,108,770 E331,450 Surface Graywacke M-4 N2,109,420 E330,730 Surface Chert M-5 N2,111,800 E327,910 Surface Dacite M-6 N2,112,670 E328,110 Surface Graywacke CH-11 N2,109,720 E330,400 18.2 Chert CH-11A N2,109,720 E330,400 168.7-177.9 Foliated Argillite CH-lli N2,109,720 E330,400 168.7-177.9 Foliated Argillite H-1 N2,111,580 E328,110 255.5 Massive Argillite H-2 N2,112,090 E327,430 61.0 Massive Argillite H-3 N2,111,580 E328,110 243.0 Massive Argillite D-16I N2,108,900 E331,350 Surface Graywacke D-36B N2,101,461 E343,083 Surface Dacite D-37 N2,106,870 E335,650 Surface Tuff SR-1 Sta. 242+71 Terror Lake Tunnel Quartz Diorite HR-7 Sta. 239+30 Terror Lake Tunnel Altered Quartz Diorite TABLE 7.4-9 7~~~--------------------------------------------~----------. 6 5 (I) LL 4 CJ 0 0 0 ... ~ ...I LL ESTIMATED INFLOW (FLOOD OF RECORD 1979) I \ II ', RECORDED FLOW AT LAKE OUTLET I \ I \\ I \ I I /--...._.,, ,. I , '"-... .... i I ~----------,, ' 111 LAKE ELEVATION '~ ... ' ........._ ~ ~, ------~ ~ 1 '-"--.,, .. -...; ---- TIME-DAYS 1979 INFLOW-OUTFLOW HYDROGRAPHS 1-u.-·~ Z:::> Ot--<( ~c >t-WCJ ...Jw w..., wO ~a: <(e:. ...I ~-------------------:-FIGURE 7.3-1 81~-----------------------------------------------r---------, (I) LL u 8 o. 4 ..... ~ ...1 LL 11 ........ ....---_, , ... '-.. ·. ,. ~ . I '' LAKE ELEVATION! I -----~, I 'i ~ ' ' ' ' I INFLOW (FLOOD OF RECORD 1979) I ,. I I , I I I ' ! ~~UTFLOW I I / / TIME-DAYS DIVERSION TUNNEL FLOOD ROUTING ' ' 18 ::!: ::::> 1- <( c 1-u w .., 0 a: !!::. 1- LL . z 0 1- <( > w ...1 w 1,088 w ~ <( ...1 1,086 '------~------------:--FIGURE 7.3-2--- 1600 1400 1200 1000 ~ ::::> ~800 0 1--w (3600 0::: a... ..__ ~400 IJ... I z 0 ~ 200 ::> w _j w A 0- q SURGE SHAFT 1----- t---------~ rTOP OF SURGE TANK --f-------EL.1339' "'-'' ,_1 [90MW PLANT l ',, "~~ '~ 60MW PLANT t;=_-=.-_ ___ [ MAXIMUM . I--~ ---~-----=.-=- L135 MW PLANT --=--= I STEEL CONC. I &. CONC. LINED LINED I I I I I I I ~D (INVERT EL 120') c""\ IL I if8 ......,... ~ l'i' ~ 2? [) 't!.UNIT RUNNER POWERHOUSE & SYNCHRONOUS BYPASS VALVE HYDRAULIC GRADE LINES --=--==-=--=-==--=--\ MAX.W.S. EL.1170' l F MIN.W.S.EL.1081 1 (INVERT k_BRADLEY LAKE EL.1025') ~ LG (INVERT EL.104d) INCLINED SHAFT ........ ' L-E (INVERT EL. 3601 ) VERTICAL SCALE: 1''= 200' HYDRAULIC TRANSIENTS HORIZONTAL SCALE: 1"=2000' FRANCIS UNITS ...__ _____ __::..:...=..=.. _ ____.;.. ___ ...:....:....::::..:::::~~=----------FIGURE 7 .4-1-__. 1600~----~--~-~--=-~~------------------------------------~--------------------------r-------/135 MW PLANT r----------~----c::O MW PLANT f--1400.....,____----r~=--=--~-~==-=-~-~-~~~~~~~~--~~~~-----------------------------;-_ __ -------------./!MAXIMUM ,~ ------HYDRAULIC "-60MW PLAN;:---=----~~ADE 1200------t-------r-----~--------------------------~--=~~-=-~~~-~~~~~:~s~~-~-~,----~M~A~x~.w~.s~E=L.~11~7~o' __ STEEL CONC E 1 & CON C. L1 NED (INVERT MIN. W.S. EL.1081' 1000~----~-L_I~N~E~D_. j-------------------------------------~E~L~~~0~25~'~)-tr=~ll~B~RA~D~LE~Y~L~A~K~E~--~~ - F (INVERT EL.1040• ) :2: ::) ~800------r-----~t-------------------------------------------4------------- o 1--w (3600 ~ ------t------t----------------------------------------~------------- INCLINED SHAFT 0... 1-~AOO------~------t-------------------------------------------~----~-------- I..L ......... I z ~200------1~~-;:i------~====~~,_~~~======--~-----------------------------~ .~s c~ _ ~__...,..__......__......__......__......tl D (INVERT E L. 360 I) w 0· --j~~~~~~·~uN~I~T~R~U~N~N=ER~-------------------------------------------------- "-..r-A ---f---' POWERHOUSE VERTICAL SCALE: 111= 200' HYDRAULIC TRANSIENTS HORIZONTAL SCALE: 1··=2000' PELTON UNITS -------~..:.::...=.....--=-.:....:...:... _ __._ ___ __:_::::~~~~-------FIGURE 7.4-2 ____... Project: BRI'IOLE"< LAI<.f: \-l'<o{'.or,•s.L~:N"-PRo-ltc<:.T Location: \\.~-..\..\~>.1 Vr;.~INSuLI'I,A\\. ((::IPPHo~-NS1°'\~·, W1so·1s') Coordinates: N'2.,10\:,,900 E3?:>1 1 350 Specimen No.: 0 -\Gl Description of Sampling Point: Du•<:.Ro? Thin Sect ion No. D-\Gl Date: "\ jl?../8:, MACROSCOPIC DESCRIPTION OF SAMPLE Degree of Weathering: \lEt~.'< SLIGH\ 10 SL\G\-\1 Structure : I'J\1\SSI\! r:_ Discontinuities : wiG{"-_ 10 \11--R'I w101: ..}C>IN\ S\"1'1<:..1 t-..}G RESULTS OF ROCK PROPERTY TESTS GENERAL REMARKS: t-.lON f- GEOLOGIC DESCRIPTION Rock Name: Gr'-r--': Will ~~-<E Petrographic Classification: s~R\<:.1\I"Z.I'.C, (ju~>.n:n.<:>o;:=t-;.LOS"~'HIC::. 1 \Jf~R'l'fiN~(},~"-1>-1'1'--1) 1 \::JI"l,.<HO\'\'ii..CY .. ->11:\(. 1 Q, ,,,, '( L.J 1'1<:.1<.. r,. .. Geologic Formation: t..l\c. 1-\lJG'r\ Co\-'\PLr,.x" QUALITATIVE DESCRIPTION Texture: C..Lt-151 IC.. 1 GRI'IINS ~ \OOx Sketch [81 Photomicrograph 0 \-\1'\\RI")( ~ODI\-\\':.D ~'( St:.RI<:..\\ r~ ( \ MINERAL COMPOSITION 'JI":>ui'I'-\:~,-Tit11'11"t. J i;L \ '"-_ 1"\. I>, 1'10 ~ 1'1 <::__ \ U.J c_, f.>,::, t::.f_\-'\f.NI) 1------,---.,.-------.r---,------.--------1 Suc,l--\1 OE\J\-_LOP\"\1"'-WI a\-~~ OR\f..\JII-..0 ~-~~RIC. or-<:.~1P,C.Li>t::,.\IC C>RIG.\1-) Fracturing: NON~ Alteration: Sf.:R.IC.I\1--z..t~noN ci' l'l'.l.DSP~fl..S l:l C.otlr\0~1 \J'F-\1--'t 1-'\INO(l. <:_'HLOR\' 1'-.f'\\10~ Matrix: \JR\\--\1'\R\L'I CL.l~'\· 'S11..t-. \'1.1'1\ERI?-.L 0~ lOG S\-\1'\LL 1'1 Sn.r-_ ICJ 1'.'---LO'--'-) oi"\1<-PIL \D\·.~\1\-\CI'-\\IO\-.). Maior % Minor qui'IRI "L '2..0 C-..LOti.I"TF.. PLA(,ICC.LP,tlt'. 30 C.L.~'I'-SIU. ':) (.{t,\C.I \ E 30 \<-fEL.D':>"I'I\1. SIGNIFICANCE TO ROCK ENGINEERING Cr:np,<-L.~>~~''"-'FPI\"!>1<..1<.., s % '2. 5 \'j IN:lu\' \'1<..1 RN 'T L'< a ..-~\J ~"·'-'--'1''' a 10 'SI<>I-JI'\'IC.C'>N"I:L'{ I N\'1..'-l<-."-'"-"- ~rc\-11';'1\0R uNOI".R L.OC>.tl. s~t\.IC.\"'"I<.t>.·not-.) \-11:\S ~(l\''\l"-.W\-11'\'T lul'.l\l<f-.IJt;_t) 't~E. {l..~c_~ I 1-J C:.G\'\\'1>.0-.\SON IG 1'>,\-.l \Jl'-li;L.II".RI'.t> \-'1;1'1-,l'.N\ Ro<:.k. Acces. % \'\uscoVI\1:: <. I Grain Size/ Distribution o. '2. - O.OG2S O .Q62.5- Q.OO?>q <0.00'3,9 % lO 2.5 5 REPORT OF PETROGRAPHIC EXAMINATION FIGURE 7.4-3 - Project: B\1..1\D'-1'-'1 lf\1-<.E \-\'it~Rot:Lr~c:.11l-'C. \::>~>-o.lr~(..T Location: K E Nl\1 Pr-.tJ IN S\JLI'I, 1\ ~ (!\~ 'O'Ra~. N 5'i0 4(0\l/ ISO' so' Coordinates: ~ 2.\Cl-:)110 , E 3'\'2.1100 Specimen No.: S-\-1 Description of Sampling Point: 0\-\ '3 5 (u~I\C..E. ), APPR())(.. Dr-.l""l\-\·11 .'2. ~t . (01-..K (\1'-.t"~A,LEr-1 '510"-l Thin Section No. S·\·1 Date: '1.}\ /'Oo MACROSCOPIC DESCRIPTION OF SAMPLE Degree of Weathering: 1-ll,r~"&\-\ "to \Jt:.\'1..'-l S\...IG.H,. Structure: 1\1\1'1.5'51\JE. Discontinuities: OC.Ct'\S\ONI\\.1 IR.Rt:.GULI\1' ,CALU\~- GEOLOGIC DESCRIPTION Rock Name: MI\SS\'1/E. ~RGoii..\.11E Petrographic Classification: C:. HL oR 1117.\::t:) \ S11-, '1, QuAI\."" z. f\~uiLL\"t E Geologic Formation: "l\1\c.\·h.lGH Co""~">'-f,_)(11 QUALITATIVE DESCRIPTION S \"l.E 1-\~111..1 Y. Pl. PIC:. l<lC..\.."' s 'e. --r-t:r-C~~±n lOx. Sketch [8] Photomicrograph 0 Texture: CLA~11C.-GP...P.IW/MfHP.IX/ c EME Ni. Vt:. ~'I SLIC.~'T c 1\ \C.I.I\S "TIC 1--------------------------t MINERAL COMPOSITION (1.1,~\J<:\L t:':l11l-\l'IT~) 0 ll. \(;.N 'TI1 i I 0 1\l 0 ~ S \L 1 · ~ n. S:. ~ 1\ II.. 'T \C. L'f~S 1------,...-~r-----,.--_;,-'--.;;_:__;_.;_;_i-'-----1 Ma"or % QUAI'-1' "l. 50 C.HI.ORI1 E I 5 CL"'(-Sn.£.* 1 5 Minor \(· tE \..0 :5~t.R PLII>GIOC:LI\SE. % 10 '2. Acces. % Sp,u~;.nE (?) 5 C 1\L C.l'T E. 3 Ml\r.,\.n:nn<:~) <..I f\LI.¥-0 fR~C.TU~"-5 UP lO I .O'N\'mi..U\OE) ~0\N\1~<:;-Fracturing: IR\l-..t;.C.\.1\..I'III..l"<..Jt>.\/1!.'1'')1 RESULTS OF ROCK PROPERTY TESTS \JNI"T w~,<;Tt,.-nt \"<>/!iii~ '\_.u.. -'a 1. <0 <0 \" s i HR-3e .G HA-1..\G. SHORE \-\f>.RONES~-53.~ 1-\.T-oG.I loNe:.nuo 1 NC»L LVP..vr:. VE.I..OC:I\ '{ '!) '2.000 f s't A)CI~~>L \..oAo-\l,l"r~ \"'rfs~c... GENERAL REMARKS: C.r-.\..(..\"T~-e.l\..1.}(..\'f'l': V\1...1...'1:;0 j UP 'TO \""om U. • .I\OE. \-{(;,f.\L.r.O. Alteration: MOOEI'AIE AL"'fi'RA\\<:IN O'f MIC..t:\ ':i f\\-..10 C.l...ll'i 1\J\IN\-.Il..f.lLS iO C 1-\l.O Q.l i£. Matrix: vtt.R'l I"INt:. SII.."T !'\No ~\..1'\'l·S\'Lii P!$\.:TIC.I..\!.'5 I.UI"'I' H C.l,\l.OR11'E. l·'\\WO'I\ f.H'\OUI-l'iS 0~ C.l>1\l!.CHJf'l<.n_ou~ \'\lqt";R\~1. ~\-..!CjC!l.. \,Qf>.l'rlllf'_ 1'\ll.'l'i. \"1\.<>CA~I..,'( l\-l<:..l.uOt<.D. SIGNIFICANCE TO ROCK ENGINEERING SI..IG Hl' A I-ll ~O'ill.I:>PIC: ~\'.WI>.\1\0t>.. \JN0\'.(1. L.CI'tO \5 ~t>-OC.I\11>\..f. SHOUI...O "'"'-0 C:,I;.Nf';t>.f\-\.'-'( ~Q\JI" 1:\11-\t'.~:S\ONP\\. (>M'\'1:\C.I..t'~S 101-11'.~ ~\..1'\Si~O OR C.t>.u.S~"-0 REPORT OF PETROGRAPHIC EXAMINATION FIGURE Grain Size/ Distribution mm "> 0 .1 0 .1·0.05 .os·o.oo <o .oos % 5 5 1S 15 7.4-4 Project: BRP>o t..t",.'{ \...r>."'r~ \4.'1ot-..c;\';.c_~t..'r>--'"-1?(\<:>.)t",_._,. Loca tion: \\r~\J I\1 f\~..:>1 N~\.>'-" ,1\t< (~?~t>.,o)l.. N 5'1°4.G. ·,W I so" so') Coordinates: N'2,10'1 1l'LO E. 3 '60 140C>(APPf>.-O")(.) Specimen ·No. : C.\-\-ll A Description of Sampling Point: C.o~t: \=ROM BOR\\.JG D\-\-\$ \<Oe..l-\\1.'1 t1.D~f>\H \Nli:.I"\\IP.L Thin Section No.(_\-\-\IA Date:O.j\4{63 MACROSCOPIC DESCRIPTION OF SAMPLE Degree of Weathering: tRI:.~~ St r ucture : OI'S\IIJ<:..TL\' \-O'-'t<'~'-0 <9 AO•'"' ()\= '00" ~ Discontinuities: i Z AIJDOM.L '<-atur:NTLO, t::..l'l'-'-""- t=\LLr._o I'Rt>,<:..-ru P..t",<; UP 10 \""'""' ''"''"-"'-. RESULTS OF ROCK PROPE RTY TESTS \..)t-.>I T W~I C,I-\T -\ ~~ lb fc;t3 "ju..-~c;G) I f>S·, 1-fR-55 .\ \-\1'\-'2..6'2. SI-IORI"_ \-1 c>.~I..ON I;.'S'S -'ijG . '3 H 1 · "''Z.. 53 Lot->C,I1'\JOIIJAl..l..j(',vl'_ \Jr-..t..OC:..I't'i (<;) 'l.OOO"s·· r~\)I.IAl.. Lol\tl ' lB,'H!> '\\fs GENERAL REMARKS: Roc..\<. \'S NoTic.r,r>,t>l...'i :St.lscr-.Pll~'-r~ \o t.U I"c~lh i,\1_\~C. t..JI-\1"-_!<.t-. Sf-:..1"-.t--.> 1\\ T""-0•~1\.'l'fH. E . GEOLOGIC DESCRIPTION Petrographic Classification: S T;.ll, I<:_ I, l "l. I'. 0 1 S l L, '( ~~ Q... (,.I I_ L I\ t"~ Pn.e:.\<> ~--''<'-"'...,1'"- Geologic Formation: •· Me 1-\ u '-> 11 C. OMI''-f'-)<.. 11 QUALITATIVE DESCRIPTION \OQ'l<. Sketch [81 Photomicrograph 0 Texture: C.. L P. '::>\\C.-PRO \O~'il.cNn: IC.I---------------------------1 Ct>~il'\c.'-Asl•c.. ri\BRi c. SIR<HIGI....Y 01:.\/1:.1...0 P 1:: D. Fracturing: NuME-o..ou s t'II<:..P.o ~<:..o1'1c:.. I'RPIC:..\I..ll"\.l'..S < 0.0\wt'M WID!:: 01"\.\l:t-.!i"-D GF..t-J"-RI>.L.L.'I I IJ <kF-o•r.~"o.t::..Tiolo) or. IH£ C. 1'1 I (>, <:.. '-1>. S i I C. F PI~ Rl C A tv 0 S I' &>,<:..E. 0 0, l· (). 5 'IVt'M. Oc..c...I'\S\01-ll'\\.. SW/'111..1"\S ())' "C!>Rr-. I 01'.()" ~RI\<:. \U Rl=: 'S SPA<:.f~'O 0 .Ool1...,..., f'R\\"\1'\Q..'I C.<JI-\I'.SION U~Uf.\LL.'I 1-\P.I~)TP.INI'-tl. Alteration: e.o1J-:;1 or-.n..f:IG'-"'- 3 1'.RIC \1 IJ..f1 "1.10"-'> ov \-\-.\..0-0 ~A T!..:\ j .:SLIC.~\T \0 \.lf-_{'l...'( ::5 \.....\.C, ~ll C:H\.D [\\ "'T \1....~ TI O t--l j \'o s~ 101.. -y ::; o\'\ r~ 1<. "<>'-ltv 11'1'2.1\ ,,o >-) Matrix: VR 1 h f:\11..1 '--'1 c:.t..f.\ ·r . ~ '..,_~"~ f'!\R"tlL\...'1:.~ TOU SMC'IL.L \0 C>l:. 101;.\-.l"l.\"1\-,C . 'So\-\1:. (;RI'IP\-1\\ 'E "'\.JO /OR 0\~I:R C.P.R~a"-'P.<:.f':.ClU':II-'IF\i'f;.l\11'\1.. \o;:, \'I<.Ot",r..,>OL"t \,>C>..,V:_s r-.1-JT MINERAL COMPOSITION (\J1sur-.'-£.51\t-'1 ~"'-) Maior % Minor % Ac ce s. % PL.AGIOC.LA'Sl: 35 (HLORITI:. '2. PYt<.li \:. <l ~F..RIC.1 1 I; 2.0 Qu~R., • I S ... CLAY· Sn.~:. 2.() C.(>.\.. C I \l!: ~ \<: f F.LD SPAll? 5 SIGNIFICANCE TO ROCK ENGINEERING Grain Size/ Distribution <;) 1-\CULP \-_)(,1-\l()\\ S"t\ .. 0\JCI...'Y Q.\- f.\1-JI:IC>"t;Rcf'IC. D~:I'ORt-11\\10~ O.OG'2.5 Gr~1-1 ll.'J\OR \.J "'o ~".R. t...c. 1>. o . Sp.t-.N<>1H o. Ot<. 25- ?t~n..~>.'-'-~":'-,.o r-"''-'""-rlolo) s~<ou'-o o .oo<t \:It'~ ~IC.I-.>I'fl<:..r..>-.l'TL'< Lt'·-S'S \H!>N (Q,QO'\ H 'I lkllt-r \.JOI'l..t-\1'\L i o \1-\'i'. GRI\1 \.J . 8_\":_l>\:I~IHJ<..I'_ '" t.ur,_,.,'t-\.-~ii,.ING ~1'\'1 GK N0'\10.1\~\..'< \..'r,::ll'1Hf\~ ~11-\1'-11-1'\0t::..l-<-\ ''""~"-"" "'' ,,..,., -:;n r:. % \0 10 1.0 REPORT OF PETROGRAPHIC EXAMINATION FIGURE 7.4-5- Project: '2>Rr.O'-t:.'l L~<~<ll \-\yon.oa'-11.<:-.t~.'c f-l(l,oJ~•"-"'~ Location: \<.'f.\..1"'' ?r~N'"'~u'-"'· ~\\ (Pii>?l\o'1..N5'\0 '\IO,V.JIS0°50') Coordinates: N C..,ll\ ,100 £ ~ 2.&, S2.Cl (Ai>Pil.o){.) Specimen No.: S -3 Description of Sampling Point: BaRil') C. D" -\3 ~ (W\"ri..O X. ~ 'L . ~-\-~t. 0'1'.1'"'11-\ Thin Section No. S-3 MACROSCOPIC DESCRIPTION OF SAMPLE Degree of Weathering: \-R~S\-\ Structure: WELL ·l)l:V"-L OPE. o FLU)( 10 N Sli\UC:TURE 01~?\1-)t,@ G0°:!: i POf\f\\'(R,QC.U'-!.TS CJ"' <:..1-\i-RT Uf' 10 \C).,...,...)( Sc_.,., IN I',N Flri..GILI...It't 1-$'!l"f!l,l)(. Discontinuities: .)o\N'l>t-..>.c, '~~'~R't c..Lo :.r-_ P.l...ol')c, Fl.u~IG"-1/1-c<..lr.>.\loN \JAt-1011\lC. i t...liOic -ro'll;.R'\' "--I Of~ @ CJ\H~ct:l. ()~lrcNTI">''"'"-~ ~ j OC..C..PI~IC.NFIL <:_1).\..<:..i,\'..~II...Lil'IC."S RESULTS OF ROCK PROPERTY TESTS UN11Wr-.IC>\\"T-\~S \'o[~\3 '\.u.-'\,'2..04ps; HP. · 30.1 1-!A-<\.B ~1-<0I'.E 1-\Rb.cr-.r-.JS • <0'\.<0 1-h-<Dl.ZS LONC>P $ OINO.L w P.\Jf. \)r,LOC.l 'n ® 2.000"'s; A-..of.\l..lor..o. I <O,ISq nt~·c GENERAL REMARKS: Fl<.(1TUi<.F.':) INOIC.I)"l"l'll'_ Q~ :it'.'lt'~X\~1... i-.1'1:5C01~~ Cl \-\)l".t-"<:lfl..I:-H'I\\()1(\, GEOLOGIC DESCRIPTION Rock Name: C.Hr:tl.:n, \-c'-ll>l\r-..o f.:\1,(,11...1...\"( f-:. Petrographic Classification: GR ~PH I 1 I(. I CHE R I'Y ,i=>II.011)\'\'{L 0\l\\IC ARGILI...Il r:.. Geologic Formation: ·· M.c.. \-\ u C.\-1 Coi-IE''-t'.. )(" QUALITATIVE DESCRIPTION C:l.l\'1. :n ~r~ ~I~'R 't \C..I..t'. S (>,IJ ~ Q.tl..l'-l'\H'(t=_ 10')( Sketch [8J Photomicrograph 0 Texture : c L f.\~,. 1 <:.. -~ \\(),. o ~'< Loun, ~ ~ 1----------------------------i IN\~:.n.Nt>,L. \'r-.)(.\Ufl..r. o~ ~'o\\-.tl..t Po cq:> .... '( ft-0 <:._I... PI::.,. ~ I :) ~LL.Q 1 Rl 0 'i!.L!'I':i1)C:~ __ M_I_N_E_RA...-L_C_O~MP __ o_s_I_T_I_O_N....-(_v_. S~t.>_A_L_£_s_1_•_..__"'_,..,...t.-')'------l Gl\rH.H.)LI'\R t'\> , .... ,_ \-\tC.f\o-10 <:..P.'i~1o· C.!l,'<S"l"PII...'-1 t-1 E Sl ~r-. Lt'_\Jti\... \'<,I',C:.t'-'l':STC.I...'-.1 "t.'l"~t> \-l'l'l'lt:nOI-\Ol\.\'1-<IC • Gt!.ll\1-.)VI.IHL ') UIH>..I"L I :s \'fl..t'.::I'I":.IU'T. Fracturing: l-l\<:.1'-<::>·f'l\.r::.c:.-ruR~'S AR~ Q(H'\ >\C N 1 U ::IU I>.L\. '/ [:>,LON Co "( \-1 ~ 'r-1\~RI<:. c\" \\-\'!'-~RC.\I....L.I-...r~ ~-'"''"'1< i L\-.S-:l <:.<lYI\-\01-.) 1"-RI;. RI>.~Q0\-\1...'1 • Ot:l.ltckl\t=..\J \"t'-1\C:..\URt'-'.i lt.J\\HIIJ C:..\-\ li.fl... T \:'CoR \'1-\ '( RO<:..Lt\:) 'l ~. \'\o:s T \-\1..1\CO.:HJ ()..('~ l SHU"-! SC.'t\_t-,. CI'_C,\"\,.T',_n. Cl \-'rlt=..!\L.I \..l C, . Alteration: NoN'=. \1\S\SL'€. l• 1'5 f>R<>OI\I~L.t< 1H!\\ sc'I-\'E. c..c.\..lt.TITv.-_•ns 01= "TI-tF. ~A1Rl)( 1-\P\'lt'.I:\.IF\I...'S 1-lr.>.\l'r~ (3r,.l=.t-..J {\L'lER'I'-0 i3l.lT \'-<I:S \'S 1-\l'oS\<.1"-:.C G'\ 1\-1~ \41<:;1-1 ~r,_n.c..r~~.ni\<;;E o'l= <;;tU'I~I-IITt. lkl Trll~ Mf'\1 ft.'¥ (:st:.r:. ~r-:.t.cw \. \-\•Ncn Sr:.R\<:.11'\,. 1'\'l'\r.,_lL 1"~-'-t>'Sl'l'{l..(~). Matrix: C:'-r-n :5\~r~ ?AR>IC.'-':.~ lac. SI-\.1'\\..L 'lroR"-li.'SI.J~L \01\"-.l"(I\-\C.f\110\..l . t.,. 1 :s '~'":. s 1:n·\t\ "t ·t'. c \ H \>I • f.\iL. '1-:.r>.::, -r 60°/o 01' "11·\\S \--.'1'\"Tt·-:.n.IP.\.. \S G. R!\ \' H 1\ ~ { <: 1\RP.>o>-J\'1 ,r~ou ';; \-\I'll. 1'-:. R\1~ L. Ma'or c~l'.ti.."T Cu•.y·S n. E % Minor SS quM~'l"L 35 % Acces. C ALC.\1 E. SURIC\ "1E. % \ 2. SIGNIFICANCE TO ROCK ENGINEERING Grain Size/ Distribution Pnoei.,~~._t", S'\'!>,c 1-l<:, 1'\NI!i<l"tf\oi'IC. C~.H('\\1\0I'l I.H-lD\':."LI..C~t). C:.\-\I"..R"l \J 11-.1 ~uf.V\<:.\T-.1--)l:l....'l :5 \'Ill. LL \'OR~'I'\';1\.0C:.'-!'~'t, f.\~ \c 'r\t>.~li. 1...\1,'-1'. on. C:~~;.v_, Pc~-500'l<\~ I'IWRCc::.LA'5l.S 5())( 5 5-2.. 2. -\ <.I Stq· Cu\'i < o.o102S NC t'.F!':!; t..T 0>-1 \-\1\TR.I )( t:.Y,C..J:>,\lf.\110N Trcc::~wqv~;.. I.J '-"1 H'\fl, ~ n ,., ~dv (, 1 ... 0 11-1 £ R ~\\ou'-o ~l'i. cr,_,"-''-"''-'~n I) \I 1'1.1>.\RI '1-1-\l'l\~-..11.1 P.'- \"~'f"\-.R\1\-..'i. <o.2 % '30 15 ..., 3 35 \0 REPORT OF PETROGRAPHIC EXAMINATION FIGURE 7.4-6 Project: Bru:.,t)L1"~'( LA I('\:. \hol"-.or~Lt:..c...,~tc. p,,a.)l'.(."T Location: \<.EN !I. I Pr. ~,(', ~UU'I. p., \( (Atf'tt_QY,. N5'1 6 ~~·.wlsa· so' Coordinates: N IOG810 , E ~:)S~SO (Mf'\"l,ox..) Specimen No.: 0 · 3 I Description of Sampling Point: OuT C.'{'..()P , lUI-.lOI"\P, C:.CN 0\\10 t0 S Thin Section No. D· 31 Date: 8}31/83 MACROSCOPIC DESCRIPTION OF SAMPLE Degree of Weathering: SL\G\-H 10 NON.(;. Structure: Mt>.SSI\/E. Discontinuities: l.IJIOt:.L'f' '5f>AC.F..D JOit-.)Tt'-!G RESULTS OF ROCK PROPERTY TESTS NONE MI'\OE GENERAL REUARKS: GEOLOGIC DESCRIPTION Rock Name: TufF Petrographic Classification: C\.ILOR\\I"Z..\' .. 0 R\4'{01...\\\C:. C.R~~"TI'>.L Tut=F Geologic Formation: ''N\c \-\uc.\-4 CoMPLE"X. •• QUALITATIVE DESCRIPTION Texture: P'(ROC..L A '5 \1 c.; ff\o~~~'-'I D f-I"G ~ \ l: t;: 0 I N 1.>.:1 ~:>, l: "'-(1. Fracturing: COt-·HtON L'( ASOU'T 0.04m'm W\t>E:, '5P/H .. EO \, '2.mYJoo C..~L0\\1., E l=\\.\ .. f.b; C.O"'-t'\Ot-lL'( Su~-P!>oR.~LLr'-L Alteration: ~L\GI-\1 \<AoLIN- \'T\7..1~1\0N OF FSLU~P11R) E'1.1n.N51\I\:. <::.."'-OR\\1 1...1=\\\0~ ()l= \--\1C.IliS ~ C..Lf\'1-~\'Z .. f. ~P."-lt<:.L.t':.'S Matrix: G~'-.1\:.R.~LL.'( \00 H\..lE- GRII>\\t-.)~0 \a BE \llS\GLEj W\-\~R ~ \) \ Sl ~ L. ~ -C..\.\LOP-.\"t;E) f"'-.Lt>'SP!=\R 1 1\NO qu~\\.\"Z.. lOx Sketch [81 Photomicrograph 0 M:(NERAL COMPOSITION-~'i V\'!IUI>oL E.'STII-11\"1'\! Ma or % fEI...I)'S f> 1'1~ 40 l '5~NAl>l W~ ~) QUAI\H. '2..0 Minor 1-\o~~i!"E'.~l>'E Bto'TI'T'l. c \-11..01'>1,. t', SIGNIFICANCE TO ROCK ENGINEERING % '2. 4 30 Tl-ln IJV~l'.l\.0\l~ C:.'rl\.01'\.1,"'-- no~OI':.D "'-\C:.(I..O \<1'\.f\C:."tVt>..tVS I'Rol!oAI!ol...'l S't' .. t>..V'F-.. \0 LOLU~l'l. \.\-\'1; Acces. % MAIOI.ti!.Tlll':.? 4- CI\LC.I"t 1\; £..1 Grain Size/ 'Distribution % 2.5 0\1'1':.1\.11>\..L !oT'('..,..,lo.luT\-1 ft\.U9t,r>.1lf\.~. C) .5 ..... "1 li-lt'-:_ '1'1''-.'I'~St\t.)C:.'ft. oF to. '1'1'\.'r-.. 'fl\t\li.F.IJ -\o QRI\",\.l"ti'I"TIO~ P,\'\ONC. "'\Ht'~ FRI'IC:.'TUI'\.'1'\.S WILL ~{\..()O~"e\..'1 0 .I..,..., ~t'~ 1\\:.Fl..t',<:."':\"-_0 Il-l ~NI::i<J"t'I\Ut'I<:.~(Q.\.,..'M 1:!>'1':.\-lll.\JICI'\.. ll).J~t'~R LoAO. \5 '2..5 REPORT OF PETROGRAPHIC EXAMINATION ..___---------------FIGURE 7.4-7 Proj ec t: lr:.R.C\o~>, Ll\\<.1:. \--\'loll.o"-Lt=..C.\\1-.IC Prt..o~IOC.T Location: Koc'''l-< LSLI\"->o, P. \-< Coordinates: S-rr'.. 230.+ 30 Specimen No . : 1-1 R-\ Description of Sampling Point: TuNN~L Thin Section No. \-\R-\ Date:o.,;c;,;s:, MACRO SC OPIC DESCRIPTION OF SAMPLE Degree of Weathering: I-I<..E.S\-1 Stru c tur e : MI"-SSI\/'1'. Discontinuities: (E~f\MINt:.ll.. l-IAS No• St=.t-:..N (\ 0 c. I< I 1\:1 0 u I c. \1... 0 ? ) RESULTS OF ROCK PROPERTY TESTS UNI"tW\'i\C,\-\1-\((,f0,\105,\IOG .\ l'o/'if3 <)_u.-'2.?. I 5 'i '0 . ~ ; 2 '2.. '0 0 '0 . e. i '2. "?. • \1 ~A psI 1-\R-41 .1,4<;,.3,".-5 .3 1-\ 1'1 -C0 . 5 I 1 <0 .G.4-1 \ • 'l. 5 'SHot>-'t.\-\1\1'-,Cl->~.:;3-85.£._~ I e,~.lO"\ 1 '0~.0<2,. \-1-t-\O<:.."r l \1"\.3\ I \1..\.~, LoN<; IT uOIN"'-W t>o'Vr-:.. \J"'u:><.l"t'f@ 1.ClDO 1H>i f\-x,,.L lo(.l,o- ' 4 I '0 '0 '-i I 4 'I"\ '0 i I 5 ' I 4 '5 flt Is ~c:. GENERAL REMARKS: STI'\\N\:.0 \-OR \-(-\"r:.Lt:>~\"rq,; C P.LLEQ "\-\t~Rn Roc.\<..", GEOLOGIC DESCRIPTION Petrographic Classification: fiNf,-GRPI\~t;.O, SLIC.Hl\..'( '::,t.C.r<:1<.1-r 1-z..t:.o,Qu~R,..,_ 0\l::>t>,\\ t: Geologic Formation: NOT I<NClWN (p,JURI\'i>'SI<: Lt,nl\.\.)11 \'lt:) QUALITATIVE DESCRIPTION Texture: 1-\'(PIO\ot-\oR'<'I-\IC- G.RI>.NUL.I"'R i MUC.I-{ .;:,r-\1-\'r,. p LI\G. \0 C.\..P, ~ ~ 1-:. 'H\ I C) I> :S C:. ROW,-H 7:.01:-JINC,. Fracturing: NoN~ VIS I~'--"-1~ \WN. S\:.C.II()N (qur'\1'-....I'L \-:..~1-\1~\\S \o.Jf.\\.11'.'1 \Cl<.TINC.TlDI-.J \"'t>IC.t\T\VE. ()\' PI\'SI OR ~f'..\".51'.~\ S'tp,11jl~) Alteration: SLIGHT •o "-\coERI'II't SfiR\C.IT\'l.ATION Of 'PLI$,\C>C:.'-~S~ Matrix: NONIO: 2.0x Sketch~ Photomicrograph 0 MINERAL COMPOSITION (VIS\}r->.Lt:O;·p\-'\~>~H.) Maior % Minor P\.I~C.\OC.LI\~f. 45 K-f U.L.t> S\'1<11. l-&oo•c.l ~ \J A I' 'I"'L 2.5 SIGNIFICANCE TO ROCK ENGINEERING % 5 SouNo 0-.0<:.I((. M<"\'1 1:,\;. l.lN$V:R '5\R\:. S'S P.NC fcl'(>.. CONTI11c--.l '-CIC..'r<.~Q -IN ~~L.\<:.\ S\Rv-3S . MC1'1 ~"-<:.aN ;5.10'-\1.\:.~ SLJ'C.J\:.<:.1 \C) :J?f'IL.'-.\NC:> If 511'-\".'&Sl:C \CI j;, SIJ~\'\C.tt'ctllll' \-11(',\-\ 1...\-_'V\-:.L. Acces. % 1-\oll.'->'C>'-f,lol>t:. <I \:>lo.-,-.-~;. \0 S"RIC.\\'f:. \5 Grain Size/ Distribution z..o-1.0 1.0 ·0-5 <o.s % 'l.5 GO IS REPORT OF PETROGRAPHIC EXAMINATION FIGURE 7.4-8 - Project: '"''~'oR \....IAKI:: \-hon..oi= ... Lt:.C\1'..1<: ?r:to.:~t::c.T Location: \-\oo1P.Y< l SL~A~o, 1-\ K Coordinates: S-u~. '2.42.+11 Specimen No.: SR-\ Description of Sampling Point: luNNEL Thin Section No. SR-I Date: C\fl/ e>~ MACROSCOPIC DESCRIPTION OF SAMPLE Degree of Weathering: S\...\~'r\\ •o t"'.:oo~1l.C\\t.; 0<::.C:R510Nl">\.. IRON 0~\0'C. S\1'1\NI"NC. OI:S"3E\'\U.ll\"IX:"O T\-\1\.UU(,"()I.)\" j PO'::>S \IZ>Lc 1-<.i>,QLIN\\li ... A'li<.J~ 0\'-r{" ... LO:S.'I'I'\RI;>:\ Structure: \v\ r-.cos 1'-1 ~ Discontinuities: Jo,N,-ING l'-lr<W'I <::.L()~t--liN c:.o\'-..f:. 'SI~hPL.t:._ Ev.r.>.t\1"1-l~R ~r-.5 NQ\ S"fX.~ "9-,()<:._\< ~~ (;\.)1"-t;\0"- RESULTS OF ROCK PROPERTY TESTS UN\\l.Jt::l<:.•.--1\-IG.'2..2. lb/tt:3 'tu." '2. '2.,'e()"\ .\pSI Hp,-4~.3 \-l. ~-<0.0(0 S\-\on..~: \-\r.:o.n..'O~t--~':0-12. .0+ \-\1 -\010 . 5 "\ LoNe,, "T u mN ~'~'-\Nf.I\JE. \JEI...O<..\i 'I' @ '2.000 p:s \ Cl ~~~I... \....ol'\o- 14,000 n{se<::. GENERAL REMARKS:CRLLIC.o''Sor-,Roc:.K''. S11\1l\JH> \"OR \<.·f'~L.'OSPPIR GEOLOGIC DESCRIPTION Petrographic Classification: rl\-.1~ C.Ri?I\N\= ... 0 I sr~R\<;..\\ n.t~o Qu~>~~ , ... D1ctt..•l:t. Geologic Formation: NoT KNOuJN (A 0u•'.r.>.":;~u::. l"->\1'-US\\J"f.) QUALITATIVE DESCRIPTION \<.-ftoLD 5PA~ _jlMS~:::..<·-"' (_ «:,,-l'>•t-:~t'..O l K· "'" \.O'if'P.~ (~\1\11-H.O) B1<n lli. Sketch [81 Photomicrograph D Texture: ~ '< ~ 1 0 ,o '"'-oRt'\-11 <::. • GQ.A'-lu'-An. i l-----__:---------------------1 ~Lt<C>I()C.I...~S'I: C.CH-\HOt-lLY \::.)<.1-l\~1\'5 u\l.~\.01\-\ 'LON\ N G Fracturing: N()Nt; "'~'t!>'-t''-IN''"~ "St':.C.\\0-..I. ( Q'->1\\-..,"T'"L 'f .. 'y..~\\'!1\"T'S CUI"o'-.11"~'( \::."t.\lo.l<..\IOt-.1 \NO\C.\-,'"tl'-'t''-0\-~\'>":;\ OR Pt>.t"~~i-..Ni S\{'o,r>.>N .) MINERAL COMPOSITION Ma or % Minor PLP.~IOC.LP.':.\:. ~~ K-H.LO ~PI\ (Sool<::.) QuM•,:n. '2.5 SIGNIFICANCE TO (Vt':>\.JI'ILI:.<:.<It'll'l,.r-..) % '5 Acces. % Bt~111E. \0 SE.l'..IC.I l E. 2.5 li\-\.Ot-.1\'l \:. .(.\ ~Jl\QL\N ("?) -<:.I Grain Size/ Distribution Alteration: M<:~o~\'l.f.l>'i:.L.~ ~'h\'t'.l\:ls 1 -u~ ROCK ENGINEERING mm ~--------------------------~~~~~------~ % SI' ... QIC\\ \L..I>.\101--) C>F PL.f$;1()"-.LI>t~t:. P.C.C.Qt-\,~Ptt-.11{;.$ '1?.'< \S'ER'< l-\INOR ~ ~(JL\ N \\\'2...1'<\\C>N . Matrix: ~oNt:. Si::I'-.\C.\\\'l...flo\\ON HI~~ "'-.)'I=_P,~t;O 2..0 -\.0 \1·\\S S'PttC.It-tt>.N 1"-' C.<>t-'PI\RISON \.D-0.5 \Q I'Rt' ... l\-1, U"-l(\L\'I=.P.,\'-.0 f>I\Rt'.\oJT <Q .5 \-1.1'1.\t'~t\lr>.L. l~r>r...-.1''-t=.\-\R-\ ). So .. " 'ii1\\.,~SS Rlii..L\t'.'i' \-I.~S ?P.o~P.\~'-Y OC.C.URR\".0 l-'l::l 1'1 R\c.S\JL\ ~l= lui<I~\1·\V .. \'\.lf\JG f-\'t--10 C>.L\t"-..Rr\l•D~. '2.5 55 '2..0 REPORT OF PETROGRAPHIC EXAMINATION FIGURE 7.4-9 --------~-------------+-----------+------~~~· \POWERHOL'SE-, \. UNITS LCHAIN-LINK FENCE TAILRACE FLOW PLOT PLAN-SF6 POWERHOUSE SUBSTATION 0 ,.. ... PI I ICAU IN FEET 16' WIDE GATE (TYP). TAKE-OFF TOWER NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM= PROJECT DATUM PLUS 4.02 FT. ALTERNATIVE SF6 SUBSTATION FIGURE 7.6-1 2.212 r--------Jr----2~~~~;;~-----=::::::::::;;;iiiii1 '---DAM CREST 2,210 -2,208 :E ::l ~ 0 2,206 1- 0 w .., 0 a: 0.. -I- LL 2 0 ~ > w ...1 w ...1 0 0 0.. 2,194 DIVERSION PIPE COMBINED CAPACITY OF SPILLWAY AND MAIN DIVERSION PIPE 800 1,000 1,200 1,400 1,600 1,800 2,000 2,200 2,400 2,600 FLOW-CFS HYDRAULIC RATING CURVES MIDDLE FORK DIVERSION ------------------FIGURE 7.9-1 8 ENVIRONMENTAL ANALYSIS 8. ENVIRONMENTAL ANALYSIS 8.1 GENERAL In considering the development of a major project, regardless of type, in a remote environment, it is impossible to present a plan that will not have some degree of impact. The impact severity depends on project type, magnitude, and location. It is therefore necessary to study and evaluate the long term benefits, as well as the impacts the project will have on the environment, the region, and its people. The Bradley Lake hydroelectric project will provide benefits and serve the developing area of southcentral Alaska and more specifically the Kenai Peninsula. The project location, on the eastern slopes of Kachemak Bay, places the project in an area of remarkable peaks, glaciers, wildlife, and subalpine terrain which have a high aesthetic quality. The project area has a high wilderness quality with a high diversity of wildlife species, and is reasonably free from physical encroachment. In studying the project, the COE conducted environmental studies and has identified the affects of project development on biological and sociojcultural resources. Involvement of concerned agencies and the people of the region allowed for communication, consultation, and exchanges of information on issues affecting the people, the environment and the project itself. These studies and communication programs have been the means and basis by which the COE prepared and issued a Final Environmental Impact Statement (FEIS) on August~ 1982, responsive to the development of the COE's preferred Bradley Lake Hydroelectric project. A review of the FEIS showed the following major areas of controversy and unresolved issues: o The volume and scheduling of mitigative flow releases from project storage necessary to protect aquatic habitat in the lower Bradley River. 8-1 o The resolution of access to the project area. o The development of plans for mining gravels and for the rehabilitation of the Martin River borrow site. o The development of a plan to establish waterfowl nesting and feeding habitat in the area of the dredge spoil site. o Assessment of moose utilization of the area above Bradley Lake. The preferred Bradley Lake development, as proposed by this report, is essentially similar to the preferred concept presented and addressed by the COE. However, under the present plan, concepts have been introduced that will result in lower impacts to the environment and studies have been initiated that will provide the information, as needed, for the resolution of the above issues. 8.2 MITIGATIVE STUDIES AND EVALUATIONS 8. 2. 1 Instream Flow Studies Under the present scope, the Alaska Power Authority authorized the performance of an instream flow study with the purpose of assessing the Bradley River aquatic system to determine a flow regime which will support salmon spawning and rearing habitat. This study was performed in consideration of mitigative measures of project impact to the Bradley River fishery habitats. In addition, the economic feasibility of the Bradley Lake project could be realistically evaluated, reflecting proposed flow releases. This study was performed by the firm of Woodward-Clyde Consultants (WCC). Details of the study and the findings are presented in Appendix E of this report. 8-2 The method used for the instream flow study was the incremental methodology developed by the U.S. Fish and Wildlife Service (USFWS) Instream Flow Group. In designing an appropriate study approach, it was necessary to address several issues before estimates of acceptable flow regimes could be prepared. Key among these issues was the need to know whether: (1) any mainstream spawning occurred in the river; (2) salt water intrusion under reduced flows would progress further upstream and potentially effect spawning and rearing habitat; and (3) stream channel characteristics would allow favorable fish spawning habitat under reduced flow. The study program and methodology was presented to an interagency group attended by state and federal resource agencies, the Alaska Power Authority, SWEe and wee. The study addressed fishery resources of the Bradley River, slough and tributary habitat, mainstream habitat, and both the spawning and rearing attributes of the river system. In determining the instream flow required to maintain salmon production in the lower Bradley River, the information gathered from incremental analysis of habitat was combined with: seasonal distribution and habitat utilization data for targeted species; streamflow estimates for natural and post-project conditions; and potential changes in salinity and water temperature regimes to determine a proposed flow regime, shown on Table 8. 2-1. The salmon species considered in the study were pink, chum and coho. Habitat requirements vary with season of the year, fish species, and life history stage. The Bradley River presently provides limited habitat for these species, and many of these habitats will be lost under post-project operation. However, there is a high potential for utilization of replacement habitat that would become available if appropriate streamf~ows are provided, with indications of improving production in spawning areas of the Bradley River. ---------------- The flow regimes selected and shown on Table 8. 2-1 provides effective spawning and rearing habitat which are in excess of natural conditions. The instream study showed that post-project operation should not result in material temperature variations. Similarly, the selection of appropriate seasonal flow releases considered the needs of juvenile fish and salmon S-3 embryos for incubation, passage for outmigration and passage to and from feeding areas. 8.2.2 Access to Project Site Several means of access to the project site, other than those proposed by the preferred plans of both the COE and this report, have been studied and reviewed. In its FEIS, the COE identified an alternative access that requires extension of the East End road. This road runs northeast out of Homer through the hills above Kachemak Bay. To develop this road for project access would require extending the East End road northeastward past Caribou Lake, across Fox River Valley, and along the foothills of the Kenai Mountains to join the project road. Although parts of this road could be made to parallel or be contained within the right-of-way ~f the presently proposed transmission line, the road alignment would cross the fresh water wetlands and impact moose habitat, eagle nesting areas, river otter habitat and approach important staging and nesting areas of migrating waterfowl and shorebirds. About 20 miles of new construction would be needed, along with adequate clearing for road construction and right-of-way. In addition, to the impacts within the Fox and Sheep River wetlands, further consideration of the East End road would require additional technical and environmental studies to fully assess impacts along its entire length and to formulate appropriate mitigation recommendations. It is concluded that both environmental and economic concerns resulting from the development of this alternate access way preclude its further consideration. 8.2. 3 Martin River Borrow Site The Martin River area is considered the most economically and . ~Il.Yil:'Qil_m_entally _ a.c:c.:_e.pt,abJ~ ar-~~ fQr P9X'rQW_ of gravel and ot_her s_imilar materials needed for project construction. The preferred plan described by this report reduces the quantities of material that would be b.orrowed from the Martin River gravelled delta area in comparison to previously suggested plans. Borrow material from this site have been identified for the following project construction needs: 8-4 PROJECT ROADS Airstrip to Powerhouse Embankment Gravel Surfacing Powerhouse to Lower Camp Embankment Gravel Surfacing Rip rap (from excavation of lower-to-upper camp road) Lower-to-Upper Camp Embankment Gravel Surfacing Upper Camp to Dam Embankment Gravel Surfacing Martin River Access Embankment Gravel Surfacing BARGE BASIN-DOCK-CONSTRUCTION Embankment Slope Protection (from excavation of lower- to-upper camp road) LOWER CAMP SITE AREA Embankment AIRSTRIP Embankment (less material from tunnel excavation) POWERHOUSE & SUBSTATION CONCRETE Gravel and Sand POWER CONDUIT & WATERWAYS CONCRETE Gravel and Sand --------------------- DAM AREA & SPILLWAY CONCRETE Gravel and Sand TOTAL ESTIMATED NEEDS FOR BORROW 8-5 Borrow Quantity (cubic yards) 1,500 1,000 215,000 12,900 0 0 8,500 0 6,900 25,000 0 55,000 0 150 '000 156,000 6,000 .. 41,000 25,000 703,800 The above total quantity represents a reduction of about 333,000 cubic yards of material, when compared to the quantities for similar construction items of the preferred plan previously studied by the COE. I The areas that would need to be excavated to provide the total quantity of embankment material, gravel, and sand material would greatly depend on the depth of excavation that can be developed within acceptable environmental limits. For example, a 10 foot deep excavation would require about 55 acres assuming a 20 percent allowance for waste and bulking. The concepts for developing the borrow area will be prepared during the FERC License Application effort of the project and will consider both environmental aspects as well as availability and location of material sources. An acceptable development plan for this site, which is currently being evaluated, will review the possibility of excavating for borrow with a work area of irregular forms and shapes, and with depths of excavation varying from 6 to 15 feet. Small causeways, from where excava.ting and trucking equipment can operate, would be incorporated in the plan. Contouring during development and after construction would also be considered to ensure the area would minimize fish and wildlife habitat impacts. The plan would be submitted to resource agencies for input and comment prior to its incorporation in construction documents for the project. 8.2.4 Waterfowl Nesting Under the present concepts of project development, it is planned to spoil material excavated from the barge basin and its access channel in an area that will be enclosed by the powerhouse to camp access road embankment and the shoreland. The area identified for spoil is about 40 acres and is located east of Sheep Point. About 464,000 cubic yards of material would have to be dredged and spoiled. Disposal of these materials would be accomplished by pumping the dredged material into large compartmentalized areas. Present data on the slurry material indicates that about 18 hours of retention will be needed within thes~ diked areas to allow for settlement -of clayey silt soils. Although definitiv~ plans for the disposal-dike area have not been determined, it is proposed that upon 8-6 completion of disposal, the ground surface of the spoil area be graded to raise portions of the fill surface to above mean higher high water elevation, to provide surface drainage and ponds. The plans for developing waterfowl habitat would be prepared during the FERC License Application effort in consul tat ion with agency personnel, before incorporating into construction contracts. 8.2.5 Moose Migration Previous environmental evaluations have identified that moose use the upper flatlands of Bradley Lake as a migratory corridor to reach wintering habitat near Nuka Bay on the east coast of the Kenai Peninsula. In order to obtain a better understanding of moose migratory and dispersal patterns, the Power Authority has authorized a fall-winter 1983 study to observe moose movements across the upper reaches of Bradley Lake. This study would record the moose pattern and characteristics of moose migration froq~_, the •,;..,, Kachemak Bay area, across the upper end of Bradley Lake and over to the Nuka River Valley crossing area. The results from this study will be used as input for formulating mitigative measures regarding moose. 8 . 3 IMPACT ADJUSTMENTS 8. 3.1 Elimination of Alternative Structures The preferred plan presented in this report incorporates several modifications that either eliminate or minimize environmental impacts resulting from project development. Environmental impacts to the project have been reduced with the elimination of: o The 2,800 feet long exposed penstock from the powerhouse to the tunnel portal. o A 2-mile access road from the powerhouse to the power tunnel portal. 8-7 o The access road that would have been required for the development of the surge shaft and the surge shaft construction itself. o The exposed steel penstock and bridge, and its associated access road, needed for the power tunnel Bradley River crossing, about one half a mile downstream of the dam. The above modifications have eliminated wildlife, terrestrial and visual impacts that would have resulted had these structures been included in the preferred plan; It is estimated that about 26 acres of timber resources, consisting of mature conifer and mixed conifer-deciduous forest will be saved by the ·elimination of the penstock and access road clearing. Similarly, the visual aesthetics of the mountain slope will remain intact. The elimination of the exposed steel penstock and bridge and its associated construction work will reduce the impact to the mountain goat wintering area and movement corridor. 8. 3. 2 Additional Project Features One of the requirements of the present feasibility study was to review previous transmission line routes and to identify alternative routes that may be considered technically acceptable and which have a reduced environmental impact and may be more acceptable to the people of the region. In selecting alternative routes, a review was made of the FEIS to ascertain the concerns and impacts associated with transmission alignments previously proposed by the COE. The impacts identified were: o Encroachment on privately owned lands o Encroachment on nesting and staging areas for migratory birds Two field trips, a brief review of land ownership and preliminary soil probes along considered routes resulted in the corridor alignment presented by this report. The proposed corridor has not been presented to any agencies, or the public. Although portions of thecorridor are in the same alignment as the transmission routes studied by the COE, it will be 8-8 necessary to better assess the environmental effects of this new alignment. The first section of the proposed corridor, from the powerhouse to the Fox River and Sheep Creek deltas, is approximately 6 miles long and transverses the heavily forested area along the slopes of the Kenai Mountains. The second section, across the Fox River delta at the head of Kachemak Bay, is approximately 3 miles long and is over open terrain. Toward the northwest, the third section traverses a flat plain for about 10 miles from the delta to the tie with the Homer Electric Association transmission line. Although a 1600 feet wide corridor is offered for flexibility of line alignment, the two circuit parallel lines will actually require a right-of-way width of 225 feet plus an additional 50 feet on either side for selective cutting of trees to prevent high tree fall from interfering with the line. Only the tallest danger trees will be selectively cut in this additional width beyond the clear cut right-of-way. An assessment of these impacts will be made during the FERC license preparation period. An additional feature presented by this report, not previously identified; is the construction of a 210 bed campsite near the upper dam area of the project. Development of this campsite will require the preparation of about 3 acres of land that is found adjacent to an oblong lake, approximately 1.1 miles west of the proposed dam, near the recommended access road alignment. If developed, the camp will draw water from the lake for domestic use and fire protection. Specific utility requirements for this site have not been defined and additional baseline data are needed to ascertain and resolve such requirements, as well as, environmental impacts to the lake and the transportation corridor between the upper camp and the lower area facilities. 8-9 PROPOSED HABITAT MAINTENANCE FLOWS FOR PROJECT PLANNING PURPOSES Activity Recommendedl Month (life stage) Streamflow October Rearing 50 November Incubation 40 December Incubation 40 January Incubation 40 February Incubation 40 March Incubation 40 April Incubation/Outmigration 40/100 May Outmigration 100 June Rearing 100 July Spawning 100 August Spawning 100 September Spawning/Rearing 100/50 (1) Instantaneous m~n~um flows to be provided at the USGS gage station at RM 5.1 on the lower Bradley River .___ ________ TABLE 8.2-1 9 LAND AND LAND RIGHTS 9. LAND AND LAND RIGHTS The majority of project lands were withdrawn for the purposes of the development of a hydroelectric project by Public Land Order 3953, dated March 15, 1966, and amended by Public Land Order 4056, dated July 18, 1966. The withdrawal included approximately 38,066 acres of Federally owned land. The project reservoir and structures will require approximately 4, 300 acres. The remaining 33,766 acres will be used for watershed protection. The Bradley Lake transmission line corridor extends from the powerhouse to the new transmission line to be built by Homer Electric Association between Fritz Creek and Soldotna. The corridor is approximately 20 miles long in three contiguous sections. The first section extends northeastward from the powerhouse to the Fox River and Sheep Creek delta and is approximately 6 miles long. The second section, 3 miles long, crosses the delta at the head of Kachemak Bay in a northwesterly direction. The third section traverses about 10 miles extending toward the west from the delta to the Bradley Junction and the tie with the Fritz Creek-Soldotna line. A preliminary corridor width of 2,000 feet has been identified within which the final alignment will be established. The right-of-way for the two parallel, wood pole, 115 kV lines will consist of a 225 to 325 feet wide corridor and will encompasses approximately 750 acres of land. The borrow sources for construction materials are located in lands withdrawn for the project under Land Orders 3953 and 4056. The project facilities are located within Federal, State, and private lands. The transmission line corridor crosses mostly Federal and State lands: the Fox River Flats Critical Habitat Area on the east side but does not enter the Kenai National Moose Range Expansion, withdrawn by Public Land Order 5653, dated November 16, 1978. It does cross six identified parcels of private land, however title and ownership for these private land were not investigated in this study. 9--1 An estimate of land acquisition cost is included in the Project Cost Estimate for private lands along the transmission line. Further investigation is required within the transmission line corridor to establish the required 325 feet wide right-of-way limits. This will be accomplished during preparation of the FERC License Application for the project. 9-2 10 PROJECT SCHEDULE AND CONSTRUCTION CONTRACTS 10. PROJECT SCHEDULE AND CONSTRUCTION CONTRACTS 10 . 1 GENERAL The proposed project schedule is shown on Plate 23. The schedule has been developed to delineate the major construction and procurement contracts described below. The project schedule extends over a five year period with the initiation of construction activities dependent upon the award of a FERC license for the project. Receipt of a FERC license is anticipated in May 1985 with. commercial .operation of the units scheduled during the Fall of 1988 and final project completion before the end of 1988. The critical path involves those activities related to FERC license Application processing; design, fabrication, and delivery of the tunnel boring machine; power tunnel excavation; inclined shaft excavation; concrete tunnel lining and steel liner embedment, penstock installation, arid start· iip of tlie turoirie generators. Should award of the FERC license be delayed, seasonal scheduling problems will ensue, and the entire project schedule and commercial operation dates will be delayed. 10.2 ENGINEERING AND DESIGN Engineering and design activities will commence upon submittal of the FERC license application in February 1984. The initial thrusts of these activities will be directed toward seeping and implementing various field surveys, and conducting detailed engineering studies and analyses. The results of these studies will then be utilized in developing design criteria for final design of the various civil features and developing performance standards and specifications for purchasing the major mechanical and electrical equipment. Procurement of the turbine/generator equipment will be required at an early stage to provide data and information to support continuing work efforts on 10-1 the powerhouse auxiliary equipme:Q.t, and allow commencement of engineering and design of the powerhouse civil works and powerhouse crane. Concurrently, engineering and design of the other major civil structures and facilities will occur during 1984 and extend into 1985. Other activities scheduled within this period will include FERC licensing support activities and preparation and submittal of the various Federal and State licenses and permits required prior to construction. Environmental monitoring and agency consultation will continue as required throughout the entire schedule. 10. 3 CONSTRUCTION SCHEDULE With the exception of transmission line construction, the primary criteria utilized in developing the overall schedule was to schedule the various construction activities during the milder seasons. Upon award of the General Civil Contract, the Contractor will mobilize, and design and fabrication of the Tunnel Boring Machine (TBM) will commence. This will be followed by construction of the lower access, staging and camp facilities, powerhouse excavation, and power tunnel portal excavation, all of which must be completed to accept delivery of and commence power tunnel excavation with the TBM. Access from the barge basin and staging facilities to the reservoir area will be established in two phases. The initial phase will consist of developing a pioneer road along the final alignment utilizing work crews to develop initial headings at strategic points along the route. The initial headings will be extended until the route is completely opened, allowing access to begin construction of the diversion tunnel. The second phase, concurrent with diversion tunnel construction, will consist of roadway widening and other improvements and will be completed prior to the harsher winter months. 10-2 Construction of the cofferdams at the lake outlet will commence in March 1986, followed by construction of the main dam and excavation of the intake tunnel. Should work on the main dam be d~layed during 1986, due to the early onset of inclement weather, it can be completed during 1987 since the dam is not on the critical path. Excavation of the power tunnel using the TBM will continue through 1986 followed by excavation and lining of the inclined and intake gate shafts. Once excavation of the inclined shaft has been completed, installation of the concrete and steel lining for the power tunnel will commence from the inclined shaft and continue toward the tunnel portal. The powerhouse construction contract award has been scheduled for October 1986 with construction extending over an 18 month period. Powerhouse excavation will be performed to accommodate simultaneous work activities on the powerhouse and power tunnel during this period. Construction of the transmission facilities and switchyard are not critical to project completion since construction electrical power will be furnished by contractor supplied diesel generators. As such, these activities have been tentatively scheduled for the 1986-87 winter period. 10. 4 CONTRACTS It is unlikely that sufficient information will be available to permit the construction facilities, main dam, power conduit and powerhouse to be included within a single contract. Therefore, three major construction contracts are proposed, as well as one major equipment order and various miscellaneous supply orders. The facilities, material, and equipment encompassing each of the contracts and procurement orders are descr_ibed below. 10.4 .1 General Civil Contract The General Civil Contract will include the construction of the barge basin, access roads, construction camps, warehouse, and staging area, 10-3 powerhouse excavation, powerhouse laydown and staging area-, airstrip, borrow pits, tunnel portal, power conduit, steel liner, construction diversion facilities, cofferdams, main dam, spillway, Middle For Diversion, and the permanent camp and warehouse facilities. 10.4.2 Powerhouse Contract The Powerhouse Contract will include the construction of the powerhouse, installation of the generation equipment and auxiliary electrical and mechanical equipment and the penstock between the tunnel portal and powerhouse, powerhouse substation, and tailrace. 10.4.3 Transmission Line Contract The Transmission Line contract will include the construction of two _parallel 115 kV three phase lines to connect the Bradley Lake powerhouse substation with the new line to be built between Fritz Creek and Soldotna. The new Fritz Creek-Soldotna line will be in place and provision for the construction of a tap is included at Bradley Junction. 10. 5 SUPPLY ORDERS The major equipment order will include the design, manufacture, fabrication, and delivery of the generation equipment including two Pelton turbines, generators, governors, spherical valves, air depression system, and accessory mechanical and electrical equipment. Miscellaneous supply orders will include: o Electrical and Controls 1. Generator Breakers 2. Main Power Transformers 3. Control and Relay Boards 4. Supervisory Control and Data Acquisition Equipment 10-4 5. Station Batteries and Battery Chargers 6. 480V Load Centers 7. Hotor Control Centers 8. Isolated Phase Bus and Enclosures, PT' s and Surge Equipment 9. Plant Telephone and Paging System 10. Event Recorder 11. Diesel and Propane Driven Generators 12. Reservoir Water Level Recorders o Hechanical and Building Service 1. Powerhouse Bridge Crane 2. Station and Unit Unwatering Pumps 3. Service Water Pumps 4. Transformer Oil Treatment System 5. Lube Oil Treatment System 6. Oil Separators 7. Dirty Water PUmps 8. Air compressors System and Driers 9. Service Water Strainers and Filters 10. Special Hazards Fire Protection Systems 11. C0 2 Detection System 12. Fire Pumps, Motors, and Accessories 13. HVAC Equipment o Hydro-Civil and Power 1. Intake Gates, Guides and Operators 2. Intake Trash Racks and Bulkheads 3. Draft Tube Gate and Lifting Beam 4. Miscellaneous Large Gates and Valves 5. Construction Diversion Stop Logs o Switchyard 1. Carrier Equipment 10-5 2. High Voltage Breakers 3. Disconnect Switches o Construction Support 1. Penstocks, Tunnel Liners, and Miscellaneous Large Pipe 2. Structural Steel and Crane Rails 10-6 11. PROJECT COST ESTIMATES 11. 1 PROJECT COST ESTH1ATE SUMMARY In response to the requirements of the Alaska Power Authority and the needs of the feasibility study, a cost estimate has been prepared for the preferred 90 MW Bradley Lake project. The cost estimate is: 0 0 Bid Price Cost Overnight Cost $308,400,000 $283,019,000 A summary of the main stem accounts by FERC classification and other costs included are shown by Table 11.1-1. The summary is followed by the expenditure forecast of the overnight estimate, and the detailed estimate consisting of eleven pages. The Cost Estimate includes the following: o Direct material, labor, and construction equipment. o Engineering and design. o Construction management. o Construction distributables. o Contingency. o All-risk insurance. o Land and land rights. o Based on the Project Construction Schedule in Section 10 of this Report. o Bid price estimat·e assumes July 1983 construction start date, the Overnight Estimate assumes a present day of July 1983. o Owner's cost; including general and administrative, legal, engineering, financing cost, etc. o Escalation during the construction period only. This estimate excludes the following: o Escalation other than that during the construction period. o Interest during construction. 11-1 The Overnight Estimate is the Bid Price Estimate modified by the amount of $25,381,000, which reflects a credit for the escalation during the construction period. It is our understanding that the Alaska Power Authority will use the Bid Price Estimate, and adjust this accordingly, to develop the Nominal Cost Est·imate for project financing studies and plans. The estimates are based on conceptual level studies and drawings and a preliminary construction schedule. Representative data and budget costs received from major equipment manufacturers on items such as turbines, generators, bridge cranes and transformers . were used in the cost estimates. Estimates of major quantities are developed from the conceptual level drawings and smaller items are prorated from costs for similar past projects. Material unit prices are from several sources such as existing purchase orders, contracts on current work, publications, budget prices from suppliers and other bona fide data. Labor manhour rates were developed from State of Alaska Department of Labor publications with appropriate adjustments as required. included where applicable. Contractor's equipment costs are The economics of the Bradley Lake Hydroelectric Project is dominated by the cost of the power tunnel. Field and office investigations by SWEC engineers and the Consultants on the Technical Review Board conclude that a substantial portion of the power tunnel can be excavated using a tunnel boring machine (TBM) including crossing through the fault zones. The project cost estimate is therefore based on the contractor using a tunnel boring machine to excavate approximately 16,850 feet of the tunnel. The rates of progress for the TBM excavating the tunnel as used in the cost estimate were developed from on-site field examinations of the various rock types along the tunnel alignment, laboratory testing of rock samples of the rock to be excavated; and correlation with the progress rates being experienced on the Power Authority's Terror Lake Project. allowances are included in the estimate for full concrete In addition, lining of the entire length of tunnel. The cost estimate for the tunnel was reviewed by an expert in tunnel construction and construction costing. 11-2 The, cost of engineering and design is based on SWEC' s Bradley Lake Proposal and includes the cost of this Feasibility study. The costs for the Construction Manager were made available to SWEC by the Power Authority as were Owner's cost. Owner's cost includes previous expenditures for studies on Bradley lake subsequent to its assumption by the Power Authority. A contingency of 25 percent is applied to arrive at the Bid Price Estimate. Escalation is included at the rate of 6. 3 percent annually for the three year construction period only, assuming a start of construction date of July, 1983. 11.2 COST ESTIMATES FOR ECONOMIC ANALYSIS In determining a selected installation for development of the Bradley La~~ Project, it was necessary to cost and evaluate 60 MW, 90 MW and 135 MW installations using both Francis and Pelton type hydraulic turbine units in the powerhouse, as well as a range of different dam heights for the upper reservoir. Cost estimates prepared for each of these installations were then used in the economic evaluation computer model which assessed the merits of Bradley Lake in a mix of alternative generating and transmission line scenarios. A summary of the Present Day Estimates (Overnight) selected for the seeping economic evaluation studies are given in Table 11.2-1. It should be noted that these estimates reflect costs for interest during construction less escalation (interest at discount rate). The inclusion of this cost item complies with the .Alaska Power Authority Economic Evaluation Guidelines FY83. Having selected a preferred plan, a similar cost estimate was prepared and used in the final economic evaluatiofl study reflecting the attributes of the preferred plan in the generation planning scenarios. Plant Operating and Maintenance (O&M) costs were developed for the economic . evaluation studies, as were O&M costs for the transmission line connecting the project to the proposed Homer Electric Association line. Further, construction costs were prepared for a 230 kV transmission line that would 11-3 connect the Kenai Peninsula to the Anchorage area, as were O&M costs for this line. These cost data are shown on Tables 11.2-2 through 11.2-5. 11-4 FEASIBILITY STUDY COST ESTIMATE 90 MW PREFERRED PLAN FERC ACCOUNT DESCRIPTION 330 331 332 333 334 335 336 350 352 353 357 Production Plant Land & Land Rights Power Plant Structures Reservoirs, Dams & Waterways Turbines & Generators Accessory Electrical Equipment Mise Power Plant Equipment Roads, Barge Facility & Airstrip TOTAL PRODUCTION PLANT Transmission Plant Land & Land Rights Switcbyard Structures Switchyard Equipment Transmission Line TOTAL TRANSMISSION PLANT Construction Distributables Construction Camp · Mobilization/Demobilization Other Construction Items Construction Management TOTAL CONSTRUCTION DISTRIBUTABLES TOTAL CONSTRUCTION COST Engineering & Design TOTAL CONSTRUCTION & ENGINEERING Owner's Cost. TOTAL CONSTRUCTION & INDIRECTS Contingency BID PRICE ESTIMATE Escalation OVERNIGHT ESTIMATE* *Present day as of July, 1983. ($ in OOO's) 2,783 9,~43 87,715 16,829 4,501 4,411 13,474 139,156 11 1,940 1,279 7 1 599 10,829 24,263 10,476 13,133 14 1 243 62,155 212,100 28 1 500 240,600 6 1 100 246,700 61 1 700 308,400 (25 1 381) 283,019 '-----------TABLE 11.1-1 EXPENDITURE FORECAST OF OVERNIGHT ESTIMATE (PRESENT DAY 7 /83) BRADLEY LAKE PROJECT ALASKA POWER AUTHORITY Calendar Year 1983 1984 1985 1986 1987 1988 Total Overnight Estimate Dollars in Thousands 2,200 8,200 65,990 78,160 83,080 45,389 283,019 PG 2 OF 13 '-----------TABLE 11.1-1 ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA POWER AUTHORITY STONE & WEBSTER ENGINEERING CORPORATION PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT ORDER OF MAGNITUDE ESTIMATE ~AIN SUB CORP CC STEM ACCT ACCT ST M L DESCRIPTION 330 1000 1000 0 •:l 0 LAND ~ LAND RIGHTS 90 Mil PLANT FEASIBILITY STUDY COST ESTIMATE GUAN UN 330 3000 0 0 0 0 ENVIRONMENTAL MITIGATION I LS I LS 1 LS 330 5000 0 0 0 0 EXHIBIT R -RECREATION 330 TOTAL LAND ~ LAND RIGHTS POWER PLANT STRUCTURES & IMPROVEMENTS 1000 7101) POWER HOUSE 1100 7100 2 A A EXCAVATION-UPPER BENCH 1110 7100 2 A A EXCAVATION-FIRST STAGE 1120 7100 5 A A BACKFILL-SELECT TEMP. 1130 7100 1 A E REMOVAL OF TEMP. FILL 1200 7100 2 A A EXCAVATION-SECOND STAGE 1201 7100 5 A A BACKFILL-COI!"ON 1202 7100 7 A A ROCK BOLTS . 1320 7100 10 A E SURFACE CLEANING 1511 7100 11 A E CONCRETE 1522 7100 15 A E FORMS-STRAIGHT 1523 7100 16 A E FORMS-CURVED 1524 7100 19 A E REINFORCING 1520 7100 14 A E SURFACE FINISH 1530 7101) 22 A E EMBEDMENTS 1610 7100 20 A E STRUCTURAL STEEL 1630 7100 99 A E ARCHITECTURAL ALLOWANCE 1650 7100 31 A E FIRE PROTECTION-WATER 1660 7100 31 A E PLUMBING ~ DRAINAGE 1670 7100 31 A E HEATING ~ VENTILATION 1680 7100 41 A E LIGHTING TOTAL POWER HOUSE 1000 CY 53000 CY 1380 CY 1380 CY 13800 CY 1180 CY 120 EA 6900 SF 4600 CY 39200 SF 4650 SF 278 TN 16000 SF 22000 LB 270 TN 1 LS 1 LS 1 LS 1 LS 1 LS DATE OF ESTIMATE 10/24/83 BID PRICE DATE-JULY 1983 UNIT COST 0.00 2,226,000.00 556,500.00 14.54 14.54 6.57 5.41 24.23 6.78 364.14 1.02 213.29 38.59 54.24 3,175.30 1.02 5.93 3,710.92 722,635.00 75, B41. 50 665,215.00 78,870.50 175,449.00 JOI !4500 ?6 1 OF!! PG 3 OF 13 TOTAL COST 0 2,226,000 556,5•JO 2,782,500 14,537 770,466 9,070 7,470 334,353 a,ooo 43,697 7,017 981,123 1,512,708 252,216 882,733 16,272 130,515 1,001,948 722,635 75,842 665,215 78,871 175,449 7,690,138 ..__ _________ TABLE 11.1-1 ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA POWER AUTHORITY STONE & WEBSTER ENGINEERING CORPORATION DATE OF ESTIMATE 10/24/83 BID PRICE DATE-JULY 1983 PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT MAIN SUB CORP CC STEM ACCT ACCT ST M L DESCRIPTION ORDER OF MAGNITUDE ESTIMATE 90 ~~~ PLANT FEASIBILITY STUDY COST ESTIMATE QUAN UN ------------------------------------------------- ~.,., .,j.j,. 1700 ilOO STATION YARD 1710 7100 98 A A CLEARING @ POWER HOUSE 2 AC 1711 7!00 99 A E SRADE,DRAIN & LANDSCAPING 5 AC 1722 7100 99 A E FENCING ~ GATES 1 LS 1730 7100 41 A E LIGHTING I LS 1740 7100 31 A E WATER SUPPLY 1 LS TOTAL STATION YARD 2000 HISC BLDG ~ STRUCTURES 2400 9220 26 A A WAREHOUSE & SHOP 1 LS 2500 8220 26 A A me 1 LS TOTAL HISC BLD6 ~ SiR 3000 8220 OPERATORS VILLAGE .3100 8220 STRUCTURES 3110 8220 26 A A PERMANENT CAMP 1 LS 3120 8220 26 A A SINGLE FAMILY RES. 1 LS 3200 8220 SERVICES 3210 8220 31 A A WATER LS 3220 8220 31 A A SEWER LS 3230 8220 41 A A L!SHTING LS 3300 8220 99 A A SR!JUNDS LS TOTAL OPERATORS VILLAGE 331 TOTAL POWER PLANT STRUCTURES ~ iMPROVEMENTS UNIT COST 6,090.00 5,075.00 16,747.50 50,496.25 39,458.12 618,600.00 38,662.50 541,275.00 409,822.50 COST INCLUDED WITH TRMPORARY CAI'IP JOt !4500 PG 2 OF!! PG 4 OF 13 TOTAL COST 12,180 25,375 16,748 50,496 39,458 144,257 618,600 38,663 657,263 541,275 409,823 951,!)98 9,442,755 '--------------TABLE 11.1-1 ·ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA POWER AUTHORITY STONE & WEBSTER ENGINEERING CORPORATION DATE OF ESTIMATE 10/24/83 BID PRICE DATE -JULY 1983 PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT ORDER OF MAGNITUDE ESTIMATE 90 ~II PLANT FEASIBILITY STUDY COST ESTIMATE MAIN SUB CORP CC STEM ACCT ACCT ST M L DESCRIPTION QUAN UN 332 RESERVOIRS, DAMS & WATERWAYS 3000 3000 RESERVOIR 3110 3000 98 A A CLEARING 2480 AC 3200 4100 ROCI<FILL DAI'I-1180 POOL ELEVATION 32!0 4100 COFFERDAM & PUMPING 3211 4100 6 A A U/S COFFERDAM 1 LS 3212 4100 97 A A PUMPING & MAINT. 24 KO 3213 4100 1 A A RE!1!JVAL 1 LS 3220 4100 6 A A DIS COFFERDAM II/ MAIN DAM 1 LS 3300 4100 EXCAVATION 3311 4100 I A A UNCLASSIFIED 63500 CY 3312 4100 2 A A SOLID ROCK-TOE SLAB 3200 CY 3313 4100 10 A A FOUNDATION PREPARATION 1900 SY 3J14 4100 8 A A DR ILL & 6ROUT 1 LS 3400 4100 CONCRETE-FACE ~ TOE SLAB 3411 4100 19 A A REBAR 563 TN 3412 4100 15 A A FORMS 131100 SF 3413 4100 11 A A CONCRETE 8940 CY 3414 4100 99 A A DEFLECTOR 64300 LB 3500 4100 EMBANKI1ENT 3511 4100 A A QUARRY & PLACE 3512 4100 6 A A ROCKFILL 278700 CY 3513 4100 6 A A SELECT FILL 83000 CY 3514 "4100 6 A A RIP-RAP-HEAVY 2400 CY TOTAL ROCKFILL DAM EXCL RESERVOIR UNIT COST 461.27 293,056.40 24,277.50 135,954.00 o.oo 14.57 50.71 5.50 86,239.08 2,114.84 28.59 203.66 2.29 10.47 12.56 104.66 JOt 14500 PG 3 OF!! PG 5 OF 13 TOTAL COST 1,143,956 293,056 582,660 135,954 f) 924,973 162,282 10,456 86,239 1,!90,655 3,748,608 1,820,732 147,432 2,916,958 1,042,443 251,191 13,3!3,638 '------------TABLE 11.1-1 ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA POWER AUTHORITY STONE & WEBSTER ENGINEERING CORPORATION PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT MIN SUB CORP CC STEM ACCT ACCT ST K L DESCRIPTION ORDER OF MAGNITUDE ESTIMATE 90 Mil PLANT FEASIBILITY STUDY COST ESTIMATE QUAN UN ------------------------------------------------- 332 2900 4200 SPILLWAY 2911 4200 I A A EXCAVATION-COHI!ON 8500 CY 2912 4200 2 A A EXCAVATION-ROCK 7300 CY 2913 4200 5 A A BACKFILL 300 CY 2915 4200 7 A A ROCK BOlTS 1800 LF 2930 4200 12 A A CONCRETE 10075 CY 2931 4200 15 A A FORMS-STRAIGHT 23000 SF 2932 4200 16 A A FORH5-CURVED 4700 SF 2933 4200 19 A A REBAR 167 TN 2950 4200 9 A A DRAINS 1 LS 2960 4200 8 A A GROUTING 80 CF 2961 4200 10 A A FOUNDATION CLEANING 3500 SY 2962 4200 18 A ll WATERSTOPS 1 LS 2970 4200 14 A A ENERGY DISSIPATOR 1 LS TOTAL SPILLWAY 5000 4700 WATERWAYS DIVERSION TUNNEL 5100 470(1 2 A A EXCAVATION-PORTAL 1550 CY 5120 4700 4 A A EXCAVATION-TUNNEL 0170 CY 5125 4700 2 A A EXCAVATION-DIS CHANNEL 600 CY 5130 4700 7 A A ROCK SUPPORTS 1 LS 5151 4700 13 A A CONCRETE 941 CY 5152 4700 19 A A REBAR 16 TN 5153 4700 17 A A FORMS-TUNNEL 15100 SF 5154 4700 15 A A FORI'IS-5TRAI6HT 2330 SF 5160 4700 24 A A STEEL STOP LOGS 76000 LB 5161 4700 12 A A CONCRETE 420 CY 5162 4700 19 A A REBAR 21 TN 5163 4700 15 A A FORtiS 1895 SF 5170 4700 8 A A GROUT RING (PLUSJ 1 LS 5180 4700 32 A A GATES ~ VALVES 1 LS 5181 4700 22 A A me STEEL 1 LS TOTAL DIVERSION It CONTROL STRUCTURE DATE OF ESTIMATE 10/24/83 BID PRICE DATE -JULY !983 UNIT COST 10.17 16.44 10.17 14.80 190.97 25.43 111.59 2,327.80 13,899.00 28.25 5.711 2,825.00 56,500.00 30.24 386.63 30.24 482,095.60 307.80 3, ;)86.84 14.92 27.43 3.62 244.17 3,856.58 23.59 148,229.90 310,419.20 256,569.04 JOI 14500 PG 4 OF!! PG 6 OF 13 TOTAL COST 86,445 120,023 3,t)Sl 26,645 1, 924,023 584,775 289,450 388,743 13,899 2,260 20,171 2,825 56,500 3,518,809 411,868 2,385,476 18, !42 482,096 289,643 54,189 225,348 63,923 274,759 102,552 80,988 44,712 148,230 310,419 256,569 4,783,?15 ------------TABLE 11.1-1 CLIENT-ALASKA POWER AUTHORITY ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE STONE ~ WEBSTER ENGINEERING CORPORATION DATE OF ESTIMATE 10/24/83 BID PRICE DATE -JULY 1983 PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT ORDER OF ~AGNITUDE ESTIMATE 90 "W PLANT FEASIBILITY STUDY COST ESTIMATE MAIN SUB CORP CC UNIT STEM ACCT ACCT ST II L DESCRIPTION QUAN UN COST ------------------------------------------------- __ ., .:,.;;;..:. 5200 4500 ~IDDLE FORK DIVERSION 5210 4500 99 A A SKY CRANE $8000/HR 1 LS 994,400.00 5211 4500 2 A A EXCAVATION 100 CY 35.60 5213 4500 10 A A SURFACE CLEANING 9000 SF 1.36 5215 4500 6 A A ROCKFILL-DAII 4500 CY 35.60 5216 4500 28 A A SHEET PILE 42 TN 1,586.52 5217 4500 11 A A CONCRETE 190 CY 324.87 5218 4500 19 A A REBAR 20 TN 3,599.05 5219 4500 15 A A FORIIS 3100 SF 42.94 5220 450(1 8 A A 6ROUT CURTAIN 1 LS 9,605.00 5225 4500 99 A A WOODEN ACCESS BRIDGE 1 LS 30,510.00 5231 4500 2 A A EXCAVAT!UN-PIPE TRENCH 6600 CY 35.60 5232 4500 5 A A BACKFILL 9250 CY 15.26 5235 4500 .33 A A STEEL PIPE o'DIA 3/S"WALL 2020 LF 562.18 5236 451'.10 24 A A SLUICE SATES 2 EA 44,917.50 5237 ~500 99 A A HISC STEEL 1000 LB 3.11 TOTAL MIDDLE FORK DIVERSION 5300 -4410 ?OWER TUNNEL 5310 44!0 HORIZONTAL @ INTAKE 5311 4410 4 A A EXCAVAT!DN-ROCK-CONV 5400 CY 328.80 5312 4410 7 A A ROCK BOLTS 25EA 450.46 5313 4410 7 A A STEEL SETS 7000 LB 2.85 5317 4410 13 A A CONCRETE 2285 CY 320.01 5318 4410 17 A A FORIIS-TUNNEL 33000 SF 7.55 5319 4410 19 A A REBAR 31 TN 4,656.82 JOI 14500 PG 5 OF11 PG 7 OF 13 TOTAL COST 994,400 3,560 12l204 160,178 66,634 61,726 7!,981 !33,!14 9,605 30,510 234,927 125,854 1,135,594 89,835 3,108 3133228 1~775,520 11,261 19,947 731,230 249,061) 144,361 TABLE 11. 1-1 ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA POwER AUTHORITY STONE ~ WEBSTER EN6INEERIN6 CORPORATION PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT ORDER OF MAGNITUDE ESTIMATE MAIN SUB CORP CC 90 Mil PLANT FEASIBILITY STUDY COST ESTIMATE STEM ACCT ACCT ST K L DESCRIPTION QUAN UN 332 5330 4410 5331 4410 4 A A 5332 4410 7 A A 5336 4410 13 A A 5337 4410 17 A A 5337 4410 16 A A 5338 4410 19 A A 5340 441!) 5341 4410 3 A A 5342 4410 7 A A 5343 4410 7 A A 5346 4410 13 A A 5347 4410 17 A A 5348 4410 19 A A 5350 4410 27 A A 6100 4430 6110 4430 6111 4430 2 A A 6112 4430 b A A 6113 4430 2 A A 6!14 4430 7 A A 6115 4430 7 A A 6116 4430 7 A A 6120 4430 11 A A 6121 4430 19 A A 6122 4430 15 A A 6123 4430 16 A A INCLINED SECTION EXCAVATION-RAISE BORE 4000 CY ROCK BOLTS 50 EA CONCRETE 1550 CY FORI'!S-TUNNEL 28650 SF FORI1S-ELBOIIS 2800 SF REBAR 22 TN HORIZONTAL FROH INCLINE TO OUTLET PORTAL EXCAVATION-TBH 85300 CY ROCK BOLTS 450 EA STEEL SETS 127000 LB CONCRETE 24030 CY FORMS 504600 SF REBAR 255 'TN STEEL LINING 1380 TN TOTAL POIIER TUNNEL INTAKE @ RESERVOIR CHANNEL EXCAVATION EXCAVATE ~ SPOIL 22300 CY EXCAVATE (INCL W/DAI!l 52100 CY EXCAVATE PORTAL 490 CY ROCK BOLTS-I' 10' 120 EA ROCK BOLTS-I I 1 5' 75 EA STEEL SETS 3700 LB CONCRETE 130 CY REBAR 16 TN FORI'!S-STRAIGHT 1170 SF FORI'IS-CURVED 1190 SF TOTAL INTAKE STRUCTURE DATE OF ESTIMATE 10/24/83 BID PRICE DATE -JULY 1983 UNiT COST 890.40 457.44 315.27 8.04 63.85 4,587.80 280.63 431.58 2. 76 350.98 6.32 4,656.82 7,203.16 15.70 1), 00 50.71 347.71 519.54 2.40 284.46 4,083.32 30.40 43.01 TOTAL COST JOI !4500 ?S 6 OFll PG 8 OF 13 3,561,600 22,872 488,669 230,345 178,766 !00,932 23,937,9!0 194,210 351,003 8,434,097 3,189,057 1,187,489 9,940,361 54,748,689 350,!j98 0 24,849 41,725 38,965 8,883 36,979 65,333 35,563 51,185 653,580 TABLE 11. 1-1 ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA POWER AUTHORITY STONE & WEBSTER ENGINEERIN6 CORPORATION PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT ORDER OF nAGNITUDE ESTIMATE MAIN SUB CORP CC 90 1'111 PLANT FEASIBILITY STUDY COST ESTIMATE STEM ACCT ACCT ST M L DESCRIPTION QUAN UN 6300 4430 GATE SHAFT 6310 4430 1 A A EXCAVATE-OVERBURDEN 1350 CY 6311 4430 2 A A EXCAVATE-ROCK ABOVE GRD 2500 CY 6312 4430 4 A A EXCAVATE-SHAFT 2350 CY 6313 4430 7 A A ROCK BOLTS 3/4" B' 75 EA 6314 4430 7 A A ROCK BOLTS 3/4" 6' 7SO EA 6331 4430 13 A A CONCRETE 800 CY 6332 4430 19 A A REBAR 41 TN 6333 4430 15 A A FORI'IS-STRAIGHT 2220 SF 6334 4430 16 A A FORI'IS-CURVED 11650 SF 6341 4430 22 A A I!ISC STEEL 1 LS TOTAL GATE SHAFT 6600 4430 INTAKE APPURTENANCES 6610 4430 24 A A GATES INCL GUIDES & HOIST 1 LS 6611 4430 24 A A TRASH RACKS I LS TOTAL INTAKE APPURTENANCES TOTAL INTAKE STRUCTURE, GATE SHAFT & APPURTENANCES DATE OF ESTIMATE 10/24/83 BID PRICE DATE -JULY 1983 UNIT COST 10.17 !5.93 904.00 63.28 49.72 242.05 3,570.80 44.58 63.28 331,655.00 433,680.70 234,704.88 iOTAL COST JOI 14500 ,PG i OF11 PG 9 OF 13 13,730 39,833 2, 124,400 4, 746 37,290 1'13, 637 146,403 98,964 737,212 331,655 3,727,869 433,681 234,7>)5 668,386 5,049,835 '-----------TABLE 11.1-1 ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA POWER AUTHORITY STONE ~ WEBSTER ENGINEERING CORPORATION PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT MAIN SUB CORP CC STEM ACCT ACCT ST M L DESCRIPTION ORDER OF MAGNITUDE ESTIMATE 90 1111 PLANT FEASIBILITY STUDY COST ESTIMATE QUAN UN ------------------------------------------------- 31'? "~ 9000 4420 PENSTOCK 8010 4420 2 A A EXCAVATION-ROCK 1380 CY 8011 4420 5 A E BACKFILL 880 CY 8015 4420 7 A A STEEL SETS 0 LB 8016 4420 7 A A ROCK BOLTS 0 EA 9200 4420 27 A E STEa PENSTOCK 80 TN 8205 4420 27 A E ROLL OUT SECTION 10 TN 8210 4420 27 A E m 30 TN 8220 4420 33 A E VALVES INCL W/ T/6 0 EA 8300 4420 11 A E CONCRETE-STRUCTURAL 720 CY 8310 4420 11 A E CONCRETE-LEAN 470 CY 9320 4420 14 A E CONCRETE FINISH W/ CONC 0 SF 8330 4420 15 A E FORMS-STRAIGHT 4600 SF 8350 4420 19 A E REBAR 115 TN TOTAL PENSTOCK 9001) 7500 TAILRACE 9120 7500 2 A A EXCAVATION-ROCK 3590 CY 9300 7500 24 A E DRAFT TUBE GATES I LS TOTAL TAILRACE 332 TOTAL RESERVOIRS, DANS & WATERWAYS DATE OF ESTIMATE 10/24/83 BID PRICE DATE -JULY !983 UNIT COST 22.24 10.65 8,695.05 9, toB.25 9,641. 45 246.66 179.99 31.35 3,324.23 19.68 46,538.75 TOTAL COST JOi !4500 PG 8 0Fl1 PG 10 OF 13 30,692 9,369 695,604 91,683 289,244 177' 592 84,597 144,208 382,286 1,905,274 70,664 46,539 117,203 371 7!4, 546 '-----------TABLE 11.1-1 CLIENT-ALASKA POWER AUTHORITY ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE STONE & WEBSTER ENGINEERING CORPORATION DATE OF ESTIMATE 10/24/83 BID PRICE DATE -JULY 1983 PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT ORDER OF MAGNITUDE ESTIMATE 90 1111 PLANT FEASIBILITY STUDY COST ESTIMATE MAI!l SUB CORP CC UNIT STEM ACCT ACCT ST ~ L DESCRIPTION GUAN UN COST ------------------------------------------------- 333 WATER WHEELS, TURBINES ~ GENERATORS 1000 7200 51 A E TURBINES-PELTON TYPE 300 2EA 4,317,950.00 RPM INCL SPHERICAL VALVES, GOVERNORS ~ MODEL TESTS 2000 7200 51 A E SENERATOR-45MN-56.3111VA 2 EA 4,096, 729.00 EXCITATION, REGULATION, GROUNDING XFI'IR, COOLING ~ SHOP TESTS 333 TOTAL TURBINes· & GENERATORS 334 ACCESSORY ELECTRICAL EQUIPMENT 1000 7300 CONDUCTORS, CONDUITS ~ CABLE TRAY 1220 7300 41 A E GENERATOR LEADS 260 LF 1,747.88 1230 7300 41 A E POWER CABLE 1 LS 666,029.00 1240 7300 41 A E CONTROL CABLE 1 LS 683,774.00 1250 7300 41 A E GROUNDING INCL CATH. PROT 1 LS 282,737.00 1320 7300 41 A E CONDUIT. 1 LS 306,988.50 1340 7300 41 A E CABLE TRAY · 1 LS 357,561.75 2000 7300 SWITCHGEAR & CONTROL E9UIPI1ENT 2310 7300 41. A E GENERATOR BREAKERS,KETAL 1 LS 408,726.50 CLAD SIIITCHGEAR,POTENTIAL XFMR,GEN. SURGE PROTECT., ETC. 2500 7300 41 A E ~AIN CONTROL & RELAY PNLS I LS 431,292.23 2610 7300 41 A E AUX SENERATORS-250KW I LS 103,175.35 DIESEL & 5KII PROPANE 2620 7300 41 A E STATION BATTERY-125V 1 LS 28,451.15 2630 7300 41 A E COMKUNICATION BATTERY I LS 21,944.65 2700 7300 41 A E SUPRV. CONTROL & DATA AQ. 1 LS 87,394.13 3000 7300 CUBICLES & APPURTENANCES 3200 7300 41 A E STATION SERVICE LOAD CTR 1 LS 174,788.25 3300 7300 41 A E MOTOR CONTROL CENTERS 6 EA 82,277.65 334 TOTAL ACCESSORY ELECTRICAL E9UIPMENT JOt 14500 P6 9 OF11 PG110F13 TOTAL COST 8,635,900 8,193,458 16,829,358 454,449 666,029 683,774 282,737 306,989 357,562 408,727 431,292 103,175 28,451 21,945 97,394 174,788 493666 4,500,978 TABLE 11.1-1 ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA PONER AUTHORITY STONE & WEBSTER ENGINEERING CORPORATION PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE MAIN SUB CORP CC STEM ACCT ACCT ST M L DESCRIPTION QUAN UN 336 336 MISCELLANEOUS PONER PLANT EQUIPKENT 1000 7400 AUXILIARY EGUIPHENT 1100 7400 35 A E UNWATERINS & LON LVL DRN 1300 7400 35 A E HISC SYSTEMS 1400 7400 35 A E COMPRESSED AIR SYSTEM 1500 7400 35 A E FIRE PROTECTION!INCL C02J 1600 7400 35 A E POWER HOUSE CRANE 150TN 2000 7400 35 •J 0 PERMANENT OPERATING EGUIP 3000 7400 35 A E COMMUNICATION SYS-LOCAL 3100 7400 35 A E KICRONAVE,SUPRV~TELEHETRY 9000 0 99 0 0 SPARE PARTS 1 LS 1 LS 1 LS 1 LS 1 E.oi 1 LS 1 LS 1 LS 1 LS TOTAL HISC POWER PLANT EQUIPMENT ROADS, BARSE FACILITY & AIR STRIP 1000 8100 ROADS-PERMANENT 1001 8100 96 A A AIR STRIP TO PH 1002 8100 96 A A PH TO DAM 1004 8100 96 A A CAMP TO MARTIN RIVER 3000 8200 96 A A DREDGED CHANNEL 3100 8200 96 A A BARBE FACILITY 4000 8102 96 A A AIR STRIP 1 LS 1 LS 1 LS 1 LS 1 LS 1 LS TOTAL ROADS, BARSE FACILITY & AIR STRIP TOTAL PRODUCTION PLANT TRANSMISSION PLANT 350 1000 7800 0 0 0 LAND & LAND RISHTS-XMSSN 1 LS DATE OF ESTIMATE 10/24 83 BID PRICE DATE -JULY 1 83 UNIT COST 71,867.25 106,174.25 150,832.50 202,647.90 874,828.50 1,301,300.00 b2, 107.50 458,708.25 1,183,000.00 175,087.50 7,026,337.50 471,975.00 3, 560,043.00 1,144,410.00 1,096,000.00 11,130.00 JOt 14500 PS 10DF1! PG 12 OF 13 TOTAL COST 71,867 106,174 150,833 202,648 874,829 !, 301,300 62,108 458, 7•j8 1,183,000 4,411,466 175,088 7,026,338 471,975 3,560,043 1, 144,410 1,096,000 13,473,853 139,155,455 11, !30 '-------------TABLE 11.1-1 ORDER OF MAGNITUDE ESTIMATE 90 MW PLANT FEASIBILITY STUDY COST ESTIMATE CLIENT-ALASKA POWER AUTHORITY STONE & WEBSTER ENGINEERING CORPORATION DATE OF ESTIMATE 10i24 83 BID PRICE DATE -JULY 1 83 PROJECT-BRADLEY LAKE HYDROELECTRIC PROJECT ORDER OF MAGNITUDE ESTIMATE KAIN SUB CORP CC 90 Mil PLANT FEASIBILITY STUDY COST ESTIMATE STEM ACCT ACCT ST K L DESCRIPTION QUAN UN ------- ---------------------------- 352 SUBSTATION & SIIITCHING STATION STRUCTURES 1230 7600 99 A E FENCING 1 LS 2110 7600 5 AE SUBSTATION FILL 16500 CY 2115 71:00 2 AE RIP-RAP 700 CY 2116 ?bOO 5 A E CRUSHED ROCK 185 CY 2410 7600 99 A E IIISC. WORK 1 LS 3110 7600 11 A E CONCRETE 515 CY 3112 7600 19 A E REBAR 52TN 3113 7600 15 A E FORI'I5-STRAIGHT 10700 SF 3114 7600 22 A E EMBEDS 1800 LB 3115 7600 99 A E i1ISC. WORK 1 LS 4130 7600 99 A E DUCTLINES ~ MANHOLES 200 LF 4210 7600 20 A E STRUCTURAL STEEL-KISC 1 LS 5220 7600 41 A E POWER SUPPLY-CAMP & SERY. 1 LS 352 TOTAL SUBSTATION & SWITCHING STATION STRUCTURES 353 SUBSTATION & SWIT4HIN6 STATION EQUIPMENT 1210 7600 44 A E INSULATORS & BUSHINGS 1 LS 1220 7600 44 A E ALUMINUM TUBULAR BUSWORK 1300 Lf !250 7600 44 A E GROUNDING SYSTEM LS 2110 7600 44 A E POWER XFMR-115KV-13.BKV 2 EA 2200 7600 44 A E POWER CIRCUIT BREAKERS 1 LS 2220 7600 44 A E DISCONNECT SWITCHES 1 LS 3210 7600 21 A E STRUCTURAL STEEL TOWERS 1 LS TOTAL SUBSTATION ~ SWITCHING STATION EQUIPMENT 357 1000 7800 49 B T TRANSMISSION LINE 1 LS TOTAL TRANSMISSION PLANT UNIT COST 27,120.00 8.50 106.22 22.06 101,022.00 269.53 3,175.30 29.95 5.93 28,984.50 124.30 73,450.00 830,781.65 13,503.50 62.49 INCLUDED IN ACCT I 334 319,196.75 323,914.50 101,671.75 120,062.50 7,599,182.20 TOTAL COST JOi !4500 P6 !10F11 PG 13 OF 13 27,120 140,210 74,354 4,081 101,022 138,807 165,116 320,412 10,679 28,985 24,860 73,450 830,782 1,939,876 13,504 81,236 638,394 323,915 101,672 120,063 1,278,781 7,599,!82 10,828,969 ------------TABLE 11.1-1 COST ESTIMATES OF STUDY ALTERNATIVES JOI 14500 8/19/83 PD 7/83 1190 POOL 1351'1N 901'1N 6011W FERC ------ -------------------------------- ACCT DESCRIPTION PELTON FRANCIS PELTON FRANCIS PELTON FRANCIS -------------------------------------------------------------------------------- (000) !000) !00.01 !000) !000) !000) PRODUCTION PLANT 330 LAND & LAND RISHTS 0 0 0 0 0 0 331 POWER PLANT STRUCTURES 7,128 8,097 5,934 6,125 5,424 5,303 332 RESERVOIRS, DAMS & WATERWAYS 81,812 93,287 75,530 84,025 70,422 78,762 333 TURBINES & GENERATORS 16,656 14,814 13,921 11,920 11,337 8,932 334 ACCESSORY ELECTRICAL EQUIPMENT 3,837 3,837 3,055 3,055 2,817 2,817 335 MISC POWER PLANT EQUIPMENT 2,691 2, 721 2,661 2,551 2,551 2,441 336 ROADS, BARSE FAC. & AIRSTRIP 14,166 14,834 14,166 14,834 14,166 14,834 TOTAL PRODUCTION PLANT 126,290 137,590 115,267 122,510 106,717 113,089 TRANSMISSION PLANT 350 LAND & LAND RIGHTS 10 10 10 10 10 10 352 SWITCHYARD STRUCTURES 1,717 1,717 1, 717 1,717 1, 717 11717 353 SWITCHYARD EQUIPMENT 2,472 2,472 2,311 2,311 2,190 2,190 357 TRANSMISSION LINE 6,725 6,725' 6,725 6,725 6, 725 6,725 TOTAL TRANSMISSION PLANT 10,924 10,924 10,763 10,763 10,642 10,642 CONSTRUCTION DISTRIBUTABLES CONSTRUCTION & PERMANENT CAMP 29,000 30,100 28,500 29,300 28,000 28,900 MOBILIZATION/DEMOBILIZATION 10,000 10,000 10,000 10,000 10,000 10,000 OTHER CONSTRUCTION ITEMS 11,800 11,800 11,800 11' 800 11,800 11, BOO CONSTRUCTION 11ANA6EI'IENT 13,200 13,200 13,200 13,200 13,200 13,200 TOTAL CONSTR. DISTRIBUTABLES 64,000 65,100 63,500 64,300 63,000 63,900 TOTAL CONSTRUCTION COST 201,214 213,614 189,530 197,573 180,359 187,631 ALLOWANCE FOR INDETERMINATES 50,286 53,386 47,370 49,377 45,091 46,919 TOTAL CONSTR. COST & AFI 251,500 267,000 236,900 246,950 225,450 234,550 ENGINEERING ~ DESISN 28,500 28,500 28,500 28,500 28,500 28,500 TOTAL CONSTRUCTION ~ ENSR 280,000 295,500 265,400 275,450 253,950 263,050 OWNER'S COST 6,300 6,400 6,250 6,300 6,150 6,200 TOTAL PRESENT DAY ESTIMATE 286,300 301,900 271,650 281,750 260,100 269,250 ESCALATION NOT INCLUDED IDC !-l ESCALATION 17,200 18,100 16,300 16,900 15,600 16,150 TOTAL PRESENT DAY ESTIMATE INCLUDING (!DC-ESCALATION! 303,500 320,000 287,950 298,650 275,700 285,400 TABLE 11.2-1 HYDROELECTRIC PLANT O&M COSTS BRADLEY LAKE HYDROELECTRIC PROJECT ITEM A. Plant Operators at $68,000 to provide daily coverage and daily maintenance. B. Plant production supervisor; assigned 100% of th~ time at $78,400/year. C. APA operations staff time at 100 hours/year. D. Consulting services contracts for operation .and maintenance. E. Department of Energy fees. F. Operating Utility administrative overhead costs. G. APA Administrative overhead costs. H. Minor operation contracts. I. Annual replacement costs. J. Miscellaneous services and supplies. K. Travel (2 trips per week to Homer) L. Property and machinery insurance M. Casualty, Workman's Compensation, auto, marine and airplane insurance. Subtotal 20% Emergency Contingency TOTAL USE ANNUAL ESTIMATED COST -1983 DOLLARS $204,000 78,400 21,500 40,000 18,800 18,800 25,000 40,000 114,700 16,900 52,000 100,000 50,000 $780,100 156,000 $936,100 $940,000 '------------TABLE 11.2-2 TRANSMISSION LINE O&M COSTS BRADLEY LAKE POWERHOUSE TO PROPOSED HOMER ELECTRIC LINE ITEM A. Substation periodic inspection and testing. B. Transmission line inspection and maintenance including SCADA communication line rental charge. C. Maintenance of SCADA System. D. Annual relay and meter inspection, testing, and calibration. E. Right-of-way clearing, inspection and maintenance. F. Transmission line loss insurance. G. Operating Utility administrative overhead costs. H. APA operations staff time at 200 hours. I. APA administrative overhead costs. J. APA accounting costs. K. Annual replacement costs. L. Miscellaneous supplies and services. Subtotal 20% Emergency Contingency TOTAL USE ANNUAL ESTIMATED COST -1983 DOLLARS $ 34,200 133,300 8,100 19,000 10,200 10,000 13,000 9,100 8,700 2,200 7,700 4,400 $259,900 52,000 $311,900 $312,000 NOTE: Totals rounded up to the nearest $10,000; line items rounded up to the nearest $100. ~----------TABLE 11.2-3 230 KV ANCHORAGE/SOLDOTNA TRANSMISSION LINE LAND & LAND RIGHTS Allowance OVERHEAD PORTION Labor & Material Clearing @ 15% Engineering & Construction Management @ 12% Owners Costs @ 8% Contingency @ 15% Subtotal SUBMARINE CABLE Labor & Material Engineering & Construction Management @ 15% Owners Costs @ 8% Contingency @ 25% Subtotal SUBSTATIONS & SWITCHYARDS Allowance TOTAL COST $ 1,280,000 $16,000,000 2,400,000 1,900,000 1,300,000 $21,600,000 3,240,000 $24,840,000 $28,500,000 4,275,000 2,280,000 35,055,000 8,764,000 $44,000,000 $ 5,000,000 $75,120,000 ...__ ________ TABLE 11.2-4 ITEM TRANSMISSION LINE O&M COSTS ANCHORAGE/SOLDOTNA 230 KV TRANSMISSION LINE A. Substation periodic inspection and testing. B. Transmission line inspection and maintenance including SCADA communication line rental charge. C. Maintenance of SCADA System. D. Annual relay and meter inspection, testing, and calibration. E. Right-of-way clearing, inspection and maintenance. F. Transmission line loss insurance. G. Operating Utility administrative overhead costs. H. APA operations staff time at 200 hours. I. APA administrative overhead costs. J. APA accounting costs. K. Annual replacement costs. L. Miscellaneous supplies and services. M. Sinking fund for submarine crossing conductor replacement and inspection. Subtotal 20% Emergency Contingency TOTAL USE ANNUAL ESTIMATED COST -1983 DOLLARS $ 34,200 179,300 8,100 19,000 10,200 10,000 13,.000 9,100 8,700 2,200 7,700 4,400 479,300 $785,200 157,000 $942,200 $943,000 NOTE: Totals rounded up to the nearest $10,000; line items rounded up to the nearest $100. '----------TABLE 11.2-5 12 POWER STUDIES AND ECONOMIC EVALUATIONS 12. POWER STUDIES AND ECONOMIC EVALUATION 12. 1 INTRODUCTION The objectives of the power study and economic evaluation of the Bradley Lake Project are to identify the economic advantages or disadvantages of the Project for the Railbelt and to select the plant capacity. The analyses were performed using data from several sources, including the FY83 Power Authority economic guidelines, previous Bradley Lake studies performed by other organizations, and the Harza-Ebasco Susitna FERC application dated July 1983. The primary tool used in this evaluation was a computer program developed by SWEC and the Massachusetts Institute of Technology for the Electric Power Research Institute. This program, Electric Generation Expansion Analysis System (EGEAS), provides the capability to automatically develop electric generation expansion plans based on the characteristics and costs of alternative generation sources, existing unit characteristics and retirement dates, and load data. A mathematical optimization method (dynamic programming) is used to consider all feasible plans for installing new generation capacity to meet the load requirements. The total present worth cost for each plan is determined, with the lowest cost plan being the economically preferred plan. A detailed description of EGEAS is provided in Reference 1. Several variations in the Railbelt generation expansion plans were evaluated during the Bradley Lake power study. Using EGEAS, separate analyses were performed for generation expansion plans using thermal power plants (gas-fired combined cycle, gas-fired combustion turbine, and coal- fired steam turbine), Susitna combined with thermal plants, and the Bradley Lake Project (with and without Susitna) for the three proposed project capacities of 60 MW, 90 MW, and 135 MW. Also, sensitivity studies were performed to determine the effect of variations in the Railbelt load growth rate on the economic performance of the Bradley Lake Project. 12-1 In addition, EGEAS has a unique capability to perform a two-area analysis which models reserve sharing and economy interchange between two connected utility systems. This capability was used in .the Bradley Lake study to evaluate the effect of transmission limitations on the present worth costs of the optimized expansion plans associated with the Kenai Peninsula. The current transmission tie between the Kenai Peninsula and Anchorage is a 115 kV transmission line. The addition of a 230 kV line with its substations and switching stations, between Anchorage and Soldotna, would cost about $75 million (Table 11.2-4). Therefore, an assessment of the differences in transmission costs associated with generation expansion plans including and not including the Bradley Lake Project is essential to the power study. This was accomplished using the EGEAS two-area analysis capability. The primary data source for the study was the recent Harza-Ebasco Susitna FERC application dated July 1983 (Reference 2). Information derived from this document included items such as fuel prices and escalation rates, new generation alternatives, Susitna characteristics, and existing generation units in the Railbelt. The Railbelt electric load forecast used in the Bradley Lake study was also derived from this source. The load forecast, titled "Sherman H. Clark Associates NSD Case," has an average annual com- pounded load growth rate of about 2.8 percent for the period 1983 through 2007. 12. 2 METHODOLOGY The Bradley Lake and Susitna projects have been the subject of previous reports and projections for the power requirements of the Railbelt area of Alaska. Since the Bradley Lake Project is small compared to the total Railbelt load, the relative economics of Bradley Lake can become lost in the much larger present worth costs of the entire Railbelt. The objective of this power study was to clearly and precisely define the economic advantages or disadvantages of the Bradley Lake Project. A two-phased approach was used, with one phase based on life cycle cost comparisons of Bradley Lake with other alternative generation sources and one based on optimum expansion plans developed for the Railbelt using EGEAS. 12-2 Although the Bradley Lake Project will impact the entire Railbelt Area, its greatest impact will be in the Kenai Peninsula. Most of the investment and annual expenses incurred outside the Kenai Peninsula will be common to generation plans with and without Bradley Lake. However, the small proportion that is not common is significant in the determination of Bradley Lake size and overall economics. In order to capture the essential variations in total cost to the Railbelt due to alternative Bradley Lake options, a two-area analysis was made in which the total present worth of annual expenses and investment were segregated into a Kenai area and a Railbelt-without-Kenai area. For the purposes of determining the benefits of the Bradley Lake Project, incremental differences in the costs associated with the Railbeltwithout-Kenai were combined with the total Kenai costs. This approach prevents the cost of alternatives with respect to Bradley Lake being lost in a one-area Railbelt analysis. It should be emphasized that the objective was to reduce total Railbelt costs to a minimum and not to limit the study to the Kenai Peninsula. The two-area analysis was also required to assess transmission requirements between the Kenai Peninsula and the Anchorage systems. The transmission requirements were a significant factor in the evaluation of the Bradley Lake Project. The computer program EGEAS was selected specifically for its unique ability to perform a two-area analysis and optimize the whole Railbelt area while maintaining the identity of the Kenai Peninsula, and to include the effects of transmission limitations on the overall optimization. These concepts will be expanded in the following sections. 12.2 .1 Electric Generation Expansion Analysis System Electric Generation Expansion Analysis System (EGEAS) is a computer program that was developed jointly by SWEC and the Massachusetts Institute of Technology for the Electric Power Research Institute and represents state-of-the-art methodology. Representatives of 15 electric utilities were intimately involved in the development and testing of the program. It incorporates a number of optimization methods and generation dispatch algorithms within one modular set of programs using one common data base. A short description is given here of those particular features that were used for this project. 12-3 In EGEAS, each plan is evaluated in terms of present worth of all expenses incurred over the study period including fuel cost, operation and maintenance cost, and investment. Investment in a particular unit can be considered to be a one-time expense at the time of unit installation, or an annual cost of interest and depreciation may be used to represent the cost of capital for each year of the economic life of the unit. Expansion plans may be developed for 20 years during which system load will grow as specified. An end-effects period can also be used to extend the economic analysis for any number of years. During the end-effects period, the load is assumed to stop growing in the 20th year. New generation installed during the first 20 years will be retired at the end of its economic life and replaced in-kind during the extension period. Fuel costs can be escalated in the end-effects period at a rate different than that used in the expansion period. The program develops the preferred plan based on minimum present worth of costs over both the expansion period and the end-effects period. Generation expansion plans are developed automatically and optimized by EGEAS based on characteristics and costs of alternative generation sources, existing unit characteristics and retirement dates, and load data. A mathematical optimization method (dynamic programming) is used to consider all feasible plans for installing generating capacity to meet the new generation requirement. Several thousand plans may be analyzed and the one-hundred least cost plans are retained for printout. The plans are printed in order of least cost. The ability to retain and list suboptimum plans allows the user to consider other plans that may be better for the short term (20 years) as compared to the long term (50 years), particularly if the long term advantages of the 11 optimum 11 plan are relatively small compared to the short term advantages of another plan. Two areas, 11 A11 and 11 B, 11 can be modeled by EGEAS. In this formulation, area 11 A11 is optimized for a fixed expansion plan in 11 B. 11 Stated another way, a small system connected to a large system by limited transmission capacity may be optimized without involving the whole pool in the optimization process, but including the reserve sharing and economy interchange provided by the large system up to the limit of the transmission system. 12-4 As a practical matter, EGEAS provides a very economical and yet accurate method for performing the Bradley Lake studies. Even though probabilistic production cost simulation using conventional methods (Booth-Baleriaux convolution) is relatively efficient compared to hour-by-hour simulation, a new method (the Method of Moments) devised for EGEAS is an order-of-magnitude faster than Booth-Baleriaux and produces identical results. Furthermore, because of its water storage characteristics, the Bradley Lake Project lends itself to an annual load duration curve analysis rather than monthly or a more frequent sub-yearly analysis. The slight loss in accuracy in representing unit maintenance by using an annual load duration curve is more than offset by the ability of the program to perform many studies at relatively low cost with a true system optimization in the process. Maintenance is modeled by derating units by an amount equal to the expected time on maintenance. Two separate economic analyses were performed for the power study as follows: A. Life Cycle Cost Bradley Lake was compared unit-to-unit with each feasible power supply alternative in terms of levelized energy costs for a range of capacity factors. B. Railbelt Generation Expansion Optimization Railbelt power supply scenarios were developed and optimized by EGEAS from the feasible energy supply alternatives (Bradley Lake, Susitna, combined cycle, combustion turbines, and coal-fired steam plants) and economic evaluations were performed on a net present worth cost basis. 12.2. 2 Life Cycle Cost In general, there is supply the system load. a need for several different types of capacity to Base load, intermediate, and peaking capacity is one broad generalization. For fossil fueled plants, base load capacity is characterized by high investment and low energy cost and is expected to run 12-5 at high capacity factors. Intermediate load capacity has lower investment and higher production cost than base load and may be expected to follow morning and evening loads on the system. Peaking capacity usually has lower investment and higher fuel costs than the other two types and tends to be used only during system peak load periods and, as a result, is characterized by low capacity factors. Host systems need all three types and each will be selected as an economic choice over a particular range of capacity factors. A life cycle bus -bar cost analysis is one in which the cost of energy in mills/kWh, levelized over the life of the unit, is computed for various assumed capacity factors. The two major components of this analysis are investment and operating expense. Typical life cycle cost curves are shown in Figure 12.2-1. Each pair of life cycle cost curves cross at a particular capacity factor which may be designated as the break-even capacity factor. The lower investment/higher fuel cost alternatives will be the economic choice at capacity factors lower than break-even and the other unit will be more economical at all other capacity factors. For instance, it can be seen from Figure 12.2-1 that peaking capacity is more economical than other sources for capacity factors less than about 10 percent, intermediate capacity has an economic range of 10 percent to 40 percent, and base load units are economical at capacity factors higher than 40 percent. The life cycle analysis was useful for several purposes. First, it was used to determine which fossil-fueled alternative would be the most economical source within the Bradley Lake capacity factor range and the difference in bus-bar cost between this alternative and Bradley Lake. Also, the life cycle analysis was used to screen fossil-fueled alternatives to be included in the EGEAS optimization (an alternative that is not economical at any capacity factor in the life cycle analysis will not be selected for installation by EGEAS). 12-6 12.2.3 Generation Expansion Optimization with EGEAS A meaningful study of the Bradley Lake Project must take into account the relative isolation of the Kenai Peninsula from the remainder of the Railbelt Area, from the standpoint of both supplying the Kenai load and distributing Bradley Lake generation. Currently, the transmission tie between Kenai and Anchorage is limited to approximately 40 MW and consists of one 115 kV transmission line. Single contingency planning requires that the system continue to operate with the loss of this circuit. This is currently accomplished by installing enough generation in the peninsula to supply the load, with the tie used only as back-up. When Bradley Lake comes on line in 1988, and depending on the capacity installed, this transmission capacity may have to be increased to allow full utilization of the Bradley Lake generation to the Railbelt. In the alternatives that do not include Bradley Lake, the tie capacity may also have to be increased to allow the load in the Peninsula to be supplied from other Railbelt sources or to allow economy interchange. Therefore, the inst~llation of new transmission circuits coincident with the installation of the Bradley Lake Project may represent early installation of circuits that will be needed at a later date in any case. An accurate assessment of the differences in transmission costs associated with plans including and not including Bradley Lake was essential to this analysis. Separate analyses were performed using the optimization program, EGEAS, as follows: I. Without Bradley Lake a. without Susitna b. with Susitna II. Bradley Lake at 60MW a. without Susitna b. with Susitna III. Bradley Lake at 90MW a. without Susitna b. with Susitna 12-7 IV. Bradley Lake at 135MW a. without Susitna b. with Susitna The following sequence was used for each of these analyses: Stage 1, (Figure 12.2-2) A single-area optimization of the total Railbelt was made. In this analysis, the "existing" capacity included the thermal generation in service in 1983 plus Bradley Lake installed in 1988 and the two stages of Susitna installed in 1993 and 2002 in those cases that include the respective hydroelectric projects. The existing thermal units and new thermal units were retired at the appropriate year in the study. The Railbelt generating reserve was maintained at a minimum of 30 percent of the peak load requirement. Stage 2, (Figure 12.2-2) The new generation installed in the Stage 1 optimization was assigned to either area "A" or area "B" as appropriate and the present worth of annual costs segregated into these two subdivisions (the total will equal the Stage 1 optimum cost). At this stage, unlimited tie capacity between the Kenai Peninsula (Area "A") and the Railbelt-without-Kenai (Area "B") was assumed and EGEAS was rerun. The one important additional piece of information that was developed at Stage 2 that was not available from the single area analysis of Stage 1 was the flow of energy over the ties between "A" and "B." From this information, it was possible to estimate the transmission ties required to provide "unlimited" tie capacity (the ties are unlimited in the sense that they do not impede economy interchange or reserve sharing). A new total present worth cost was developed at Stage 2 that included the cost of the new transmission lines (if any) between the two areas. 12-8 Stage 3 (Figure 12.2-2) If appreciable tie capacity is required in Stage 2, it may be possible to develop a more optimum plan by reducing the amount of transmission capacity between areas "A" and "B". The offsetting penalty for reducing transmission capacity and cost will come in two forms: more capacity in Kenai and higher fuel cost due to limitation in economy interchange. As demonstrated in Figure 12.2-2, some capacity installed in area "A" may have to be transferred to the Kenai Peninsula if the transmission capacity is reduced. This will usually require substituting capacity available for installation on the peninsula for a different type of capacity available only in area "B" (i.e., coal-fired capacity) or in some cases the same type of capacity may be transferred but at a higher fuel cost or smaller unit size. Economy interchange takes place mainly during off-peak periods when lower cost energy in one area is substituted for high cost energy in another area. A reduction in tie capacity will limit the amount of economy energy transfer and thus cause higher fuel cost. An EGEAS two-area analysis at Stage 3 correctly models these two effects of limited ties on the overall cost to both areas. 12.2. 4 Bradley Lake and Susitna Energy Dispatch EGEAS uses a probabilistic generation dispatch method based on an annual load duration curve. Hydroelectric plants such as Bradley Lake and Susitna are modeled as "limited energy sources" and are used by the model to provide as much peak shaving as possible within the operational constraints imposed by each project. The effective storage available for daily load cycling at Bradley Lake is large enough to allow maximum peak shaving within the energy constraint. Since all three proposed Bradley Lake unit sizes produce essentially the same total energy, the evaluation of un'it size pivots on two factors: 12-9 1. transmission requirements for each size to allow economy interchange and reserve sharing between the Kenai Peninsula and the rest of the Rail be 1 t, and 2. advantages of higher capacity replacement value and the displacement of higher cost fuel by the larger generation as compared to the incremental investment of the larger units. Figure 12.2-3 demonstrates the manner in which the three different sized Bradley Lake units were modeled by EGEAS. The larger units operate at a lower capacity factor than the smaller alternatives and are loaded "higher" on the load duration curve. The hydroelectric units are "loaded" by EGEAS by finding the proper location on the load duration curve that will use all the energy available while running at maximum output as much as possible. 12.3 ECONOMIC PARAMETERS AND DATA Numerous types of data are required in order to model a Railbelt power supply plan with EGEAS and perform the economic analysis. These data include items such as the Railbelt load growth projection, fuel prices and escalation rates, costs and operating characteristics of existing and future generation units, transmission requirements, and economic parameters. Several sources of data were used in the Bradley Lake evaluations. As a part of the Susitna Hydroelectric Project evaluation, Harza-Ebasco compiled a significant part of the data required. In addition, the Chugach Electric Association has operating and cost data available for the existing generation units in their system. These data sources were supplemented, as needed, by the data contained in reports from previous Railbelt power supply studies. The parameters used in the economic evaluations are summarized in Table 12.3-1. The majority of these parameters are consistent with the FY83 Power Authority economic guidelines (Reference 3). However, certain parameters, such as fuel escalation rates and the period of time over which fuel escalation occurs, were consistent with the values assumed by Harza-Ebasco in their projection of the Railbelt load growth. 12-10 12.3. 1 Reference Case Railbelt Load Projection Detailed electric load growth projection studies have been recently completed in support of the Susitna FERC application. The results of these studies are reported in Exhibit "B" of the Susitna FERC application dated July 1983 (Reference 2). In accordance with agreements reached with the Power Authority, the Bradley Lake power study was based on a load growth projection resulting from these studies titled "Sherman H. Clark Associates No-Supply-Disruption Case." This projection, referred to as the ''Reference Case" by Harza-Ebasco, was in the middle range of the forecasts evaluated and was used as the base case in the Susitna power study. A brief overview of the analysis performed by Harza-Ebasco will be provided here. One of the primary factors in the Susitna analysis which affected the load projection was the assumed world oil price. Several oil price projections were considered by Harza-Ebasco, including the Sherman H. Clark projections. The oil price affected the need for Railbelt electric power in four ways: 1. petroleum revenues available to the State of Alaska are a direct function of the market price of petroleum; 2. the price of electricity to the consumer is impacted since most Railbelt power is generated from fossil fuels; 3. the ability to economically substitute different fuels for power generation is dependent on the price of oil; 4. the level of oil exploration and development in Alaska will vary with the world oil price. Harza-Ebasco used four interrelated computer models to project the future Railbelt load growth for each oil price projection. The four models included the following: 12-11 1. PETREV --Operated by the Alaska Department of Revenue. This model uses a probability distribution of possible values that affect Alaska petroleum revenues to predict a range of royalties and production taxes. 2. ~fAP Developed by the Institute of Social and Economic Research (ISER), University of Alaska. The MAP (Man-in-the-Arctic Program) is an economic model that simulates the behavior of the Alaska economy and population growth for each of twenty regions of the state. 3. RED --Developed by ISER and modified by Battelle Pacific Northwest Laboratories. The RED (Railbelt Electricity Demand) model is a simulation model which forecasts annual electricity consumption for each end-use sector in the Anchorage-Cook Inlet and Fairbanks-Tanana Valley load centers. 4. OGP Developed by General Electric Company. OGP (Optimized Generation Planning) is a model used to produce generation expansion plans based on system reliability, operating, and investment costs. With these models, Railbel t load growth projections for several oil price scenarios were produced for the Susitna FERC application. A complete description of the procedure is provided in Exhibit "B" of the Susitna FERC application dated July 1983 (Reference 2). A summary of the input and output data for the Reference Case is presented in Table 12.3-2. During the 28 years included in this scenario, the net Railbelt electric energy demand is projected to increase 109 percent from 2, 803 GWH to 5, 858 GWH, while the peak demand increases 110 percent from 579 MW to 1,217 MW. This load projection is shown in Table 12.3-3 for each year in the period 1983-2010. The Kenai Peninsula load is included in the Anchorage-Cook Inlet category. Table 12.3-4 shows the annual change in the Railbelt load. In order to perform a two-area analysis with EGEAS and identify the impact of Bradley Lake on the Kenai Peninsula, a separate load projection for the Kenai Peninsula was required. For this purpose, the Anchorage-Cook Inlet load from the Reference Case in Table 12.3-3 was separated into Anchorage 12-12 area and Kenai Peninsula components. The historical load in each region was the basis used to separate the projection. The historical Anchorage-Cook Inlet utility peak demand and energy requirements are shown in Tables 12.3-5 and 12.3-6, respectively. In both cases, the portion of the total Anchorage-Cook Inlet load occurring in the Kenai Peninsula varied from 14 to 16 percent during recent years. Based on this information, it was assumed that the Kenai Peninsula would represent 15 percent of the Anchorage-Cook Inlet load during the 1983 through 2007 time frame of the Bradley Lake power study. The resulting load projections for the Anchorage area and Kenai Peninsula are shown in Table 12.3-7. This projection represents a conservative estimate of the load portion occurring in the Kenai Peninsula since other recent projections (such as Reference 4) indicate that the Kenai Peninsula may grow at a somewhat faster rate than the rest of the Railbelt. Assuming a slightly higher load growth for the Kenai Peninsula would have little effect on the study, but would tend to favor the Bradley Lake Project. 12.3.2 Reference Case Fuel Price Projections As part of the Susitna FERC application, Harza-Ebasco also performed studies to determine the future availability and price of fossil fuels in the Railbelt. Projections for natural gas, coal, and distillate oil were made so that Railbelt generation expansion plans involving alternatives to Susitna (thermal plants) could be developed and evaluated on a life cycle cost basis. The fuel price projections developed for the Reference Case were used in the Bradley Lake power study to evaluate hydroelectric alternatives. A complete description of the fuels pricing studies is included in Exhibit "D" Appendix D-1, of the July 1983 Susitna FERC application (Reference 2). The fuel prices used in the Bradley Lake studies are shown in Table 12.3-8. The following major assumptions relate to these price projections: 1. The escalation in the price of natural gas will vary in the same manner as that of oil. 12-13 2. Although proven Cook Inlet natural gas reserves will be exhausted around the year 2000, it was assumed that sufficient additional reserves will be discovered to meet all future demand during the study period. No supply restrictions were imposed in any portion of the Bradley Lake power study. 3. The Beluga coal field, presently undeveloped, will be opened for development and coal will be exported to Japan. 12.3.3 Existing Railbelt Generation System The Railbelt electric power market contains two primary load centers (Anchorage-Cook Inlet and Fairbanks-Tanana Valley) and is served by several utilities and other suppliers. The 1982 Railbel t generating capacity is shown in Table 12.3-9. For the Bradley Lake power study, the market was considered to be interconnected with the addition of the transmission tie between Anchorage and Fairbanks (currently under construction by the Alaska Power Authority). The existing ll5 kV transmission tie between Anchorage and the Kenai Peninsula was subject to the capacity limitations discussed previously. For the generation expansion plans developed by EGEAS, the cost of new transmission lines was included as required. The natural gas-fired combustion turbines and combined cycle plants had no additional transmission cost since their siting flexibility allowed them to be located near the load centers. The coal plants, however, required transmission from the plant site to the nearest load center, and this cost was included accordingly. The Bradley Lake plants included the cost of transmission from the plant to the existing transmission line in all cases plus the cost of a new 230 kV line between Anchorage and Soldotna when required. The existing Railbelt generating plants were included in the generation expansion plans developed by EGEAS. These existing plants were dispatched by EGEAS along with new generation plants to arrive at an optimum generation expansion plan for the total Bradley Lake power study period. 12-14 All plants, both existing and new, were retired in accordance with the equipment lifetimes shown in Table 12.3-1. A complete listing of the existing generating plants in the Railbelt is shown in Table 12.3-10. In addition to Bradley Lake benefits for capacity and energy, an allowance was also made for the ability of the Project to provide spinning reserve. As a conservative estimate of the capability, spinning reserve benefit was applied for the Kenai Peninsula load only. This was accomplished with EGEAS by forcing the CEA Bernice #3 and /ft4 gas-fired combustion turbine units (see Table 12. 3-10) to operate continuously at no less than 20 percent capacity in those scenarios without Bradley Lake. The heat rate of these units at this reduced capacity was approximately 28,000 BTU/kWh, with the heat rates decreasing as the output approached full load to the values shown in Table 12.3-10. In the EGEAS simulations, these two units were dispatched in an optimum manner except that they never dropped below 20 percent of their full output. Thus, the scenarios without Bradley Lake had the portion of the capacity of these plants in excess of their current operating level available as spinning reserve. In the cases where the Bradley Lake Project was included, the two Bernice units were dispatched by EGEAS without a requirement to continuously operate at any level, and Bradley Lake provided spinning reserve for the Kenai Peninsula. 12.3.4 Future Railbelt Electric Generation Alternatives The development of Railbelt generation expansion plans with EGEAS required performance and cost specifications for the feasible Railbelt electric generation alternatives. A screening of alternatives was not performed for the Bradley Lake power study since the performance and cost of possible choices were evaluated in previous Rail belt studies. The technical and economic feasibility of numerous options was evaluated by Battelle Pacific Northwest Laboratories in 1982 (Reference 5). Battelle evaluated a wide variety of electric generation options, taking into account the unique characteristics of the Railbelt. The candidate resources included coal, natural gas, petroleum, peat, municipal refuse, wood waste, geothermal, hydroelectric, tidal power, wind, solar, and uranium. The most readily adaptable thermal alternatives for the Railbelt included coal, natural gas, 12-15 and oil resources. Thus, the thermal generation alternatives in the Bradley Lake power study included coal-fired steam, gas-fired combustion turbines, and gas -fired combined cycle plants. These thermal options are described in detail in Exhibit "D" of the Susitna FERC application of July 1983 (Reference 2). A summary of the thermal generation plant parameters used in EGEAS is shown in Table 12.3-11. The hydroelectric plant parameters and costs used in the Bradley Lake power study are summarized in Tables 12.3-12 through 12.3-14. Tab 1 e 12 . 3 -12 shows the Bradley Lake Project parameters developed by S\<lEC and the Susitna Project parameters obtained from the Susitna FERC application of July 1983. The capital and fixed operating and maintenance costs for the Bradley Lake options and Susitna are shown in Tables 12.3-13 and 12.3-14, respectively. 12.3.5 Sensitivity Studies The Railbelt load and price projections are dependent on numerous factors which involve various degrees of uncertainty (such as future world oil prices). Sensitivity studies were performed with EGEAS to determine the effect of load and fuel price variations on the economic performance of the Bradley Lake Project. In addition to the Reference Case (Sherman H. Clark NSD) Railbelt load growth and fuel price projections, two other cases were examined in the Bradley Lake power study. These are: 1. A Railbelt no-growth case where the 1983 load (2,803 GWH at a peak of 579 MW, net) was assumed to remain constant for the duration of the power study. The fossil fuel price projections were the same as in the Reference Case. 2. A Railbelt load growth and fossil fuel price projection titled "DOR 50% Case." This projection, developed in July 1983, was supplied to SWEC by the Power Authority. The case was studied with EGEAS for the base case (new thermal plants only) and the 90 MW Bradley Lake option. The load growth and fossil fuel projections for the DOR 50% case are shown in Tables 12.3-15 and 12.3-16. For the period 1983 to 2010, the Railbelt load shown in Table 12.3-15 grows at an average compound rate of about 2.3 12-16 percent per year. The fossil fuel price projections in Table 12.3-16 indicate that coal prices remain constant, the turbine oil price decreases by about 25 percent between 1983 and 2000 and then remains constant, and the natural gas price decreases by about 11 percent between 1983 and 2000 and then also remains constant. For comparison, the levelized fuel costs for natural gas and coal are shown in Table 12.3-17 for the Reference Case and DOR 50% Case projections. 12. 4 RESULTS The evaluations indicate that the Bradley Lake Project is economically beneficial for the Railbelt at any of the three proposed plant capacities, both with and without the presence of Susitna. Significant life-cycle savings result by using Bradley Lake in place of thermal generation alternatives (gas-fired combined cycle, gas-fired combustion turbines, and coal-fired steam plants). The capacity for Bradley Lake is dependent on and sensitive to the projected load growth rate for the Railbelt. The differences in present worth cost between the three proposed capacities for alternative load growth projections are relatively small. Of the three capacities evaluated, the 90 MW Bradley Lake Project is the economically preferable choice at the reference load growth rate of an average 2. 8 percent per year as adopted in this study. It is also economically beneficial under the DOR 50% Case. For an assumed load growth rate of zero percent per year, the 60 MW plant is the preferred choice. However, since the 90 MW Bradley Lake Project is the least sensitive to load growth variations, it appears to be the most favorable plant capacity. The Bradley Lake Project options are very close in terms of annual average energy, with only a 3 to 5 percent difference between successively larger installations. EGEAS was used to develop optimized Railbelt generation expansion plans for the various scenarios discussed in the previous sections. For each generation expansion plan, EGEAS created an extensive printout of results which was unrealistically long to attempt to reproduce in this report. Thus, the power study results are summarized in the following sections with 12-17 certain pages extracted from the EGEAS output data primarily for the base case (new thermal plants only) and the recommended Bradley Lake capacity of 90 MW. 12.4. 1 Reference Case This section presents the results of the Bradley Lake power study for the Reference Case load and fuel price projections (Sherman H. Clark NSD). Tables 12.4-1 through 12.4-14 summarize the results of the study. Present worth costs, in 1983 dollars, are shown for all cases in terms of total Railbelt cost and the portion of the cost attributable to the Kenai Peninsula alone. The present worth savings due to the Bradley Lake Project (base case cost minus Bradley Lake cost) are also shown along with the fraction of the base case cost which these savings represent. Table 12.4-1 shows the present worth costs for the plans consisting of alternatives to Bradley Lake. The thermal plant base case with the lowest present worth cost includes the Anchorage-Soldotna 230 kV transmission line and has a value of $5,832 million. This base case is compared to the "Bradley Lake without Susitna" plans. The "Bradley Lake with Susitna" plans are compared to a base case including Susitna and thermal plants which has a total present worth cost of $5,724 million. The "Bradley Lake without Susitna" cases are shown in Tables 12.4-2 and 12.4-3 for the total Railbelt and the Kenai Peninsula, respectively. For all three Bradley Lake capacities, significant savings are realized when compared to the base case. For the total Railbelt plans, the savings range from 5.1 to 6.3 percent of the base case. However, when the present worth costs are separated for the Kenai Peninsula using the EGEAS two-area evaluation, the Bradley Lake savings range from 23.1 to 33.7 percent of the Kenai Peninsula base case cost. the 90 MW Bradley Lake Project shows the largest present worth savings for the total Railbelt and the Kenai Peninsula and is the optimum choice. The incremental cost for increasing the plant capacity to 135 MW (including the additional plant capital cost plus the Anchorage-Soldotna 230 kV transmission line) is not justified since the total savings are less than for the 90 MW plant. 12-18 Additional information for the 11 Bradley Lake without Susitna'' cases is presented in Tables 12.4-4 to 12.4-11. The new generation capacity projected by EGEAS for installation in the Railbelt is shown in Tables 12.4-4 to 12.4-7 for the base case, 60 MW Bradley Lake, 90 MW Bradley Lake, and 135 MW Bradley Lake, respectively. These Tables show that the optimum expansion plans, with and without the presence of Bradley Lake, include the addition of natural gas-fired combined cycle units in the years prior to 2000, with coal-fired steam plants added in the successive years through 2007. Natural gas -fired combustion turbines were also added in the year 2000 timeframe. Tables 12.4-8 and 12.4-9 illustrate the energy generation and cost by fuel class for the ''Bradley Lake without Susitna11 case. The energy generated and total fuel cost for each year in the 1988 through 2007 period are shown for natural gas, coal, oil (existing plants only --no new oil-fired plants were added), and existing hydroelectric. Tables 12.4-10 and 12.4-11 show the Reference Case expansion plan summary for base case and 90 MW Bradley Lake cases. These summary pages, copied from the EGEAS output, show the annual Railbel t load, capacity installed and retired, reserve percent, capital cost of the new units, production cost (fuel cost plus variable O&M), fixed O&M cost for the new units, total and cumulative annual cost, and total and cumulative present worth cost. Lastly, life cycle levelized cost curves were produced for the Reference Case as discussed in earlier sections and are presented in Figure 12.4-1. These curves illustrate the relative levelized energy costs of the Railbelt generation alternatives taking into account capital costs, variable O&M costs, fixed O&M costs, and fuel costs. Other benefits which accrue to the Bradley Lake Project, such as spinning reserve, are not reflected on these curves as in the EGEAS evaluations. On the bas is of levelized bus -bar energy cost, Figure 12.4-1 shows that the three Bradley Lake capacities are the least cost alternatives compared to the thermal plants at the same capacity factor. The levelized energy cost for the 90 MW Bradley Lake Plant is about 34 percent lower than for the natural gas -fired combined cycle plant. 12-19 Tables 12.4-12 and 12.4-13 present the results for the "Bradley Lake with Susitna" plans. As expected, the present worth savings for the three Bradley Lake capacities are less due to the presence of the large Susitna plants. However, savings still result for all three plants and range from 1. 2 to 3. 1 percent for the total Railbel t base case and from 7. 4 to 22.4 percent for the Kenai Peninsula base case. In these plans, the present worth savings are essentially equal for the 60 and 90 MW Bradley Lake capacities. The 135 MW plant results in less savings, indicating that the economically preferable Bradley Lake plant capacity for the cases including Susitna should be either 60 MW or 90 MW. The "Bradley Lake with Susitna" plans did not require the addition of any new thermal generation plants after the Bradley Lake on-line date of 1988. In the succeeding years, the existing generation plants with Bradley Lake Project and Susitna (Watana in 1993 and Devil Canyon in 2002) were sufficient to meet the Railbelt Reference Case load with adequate reserves. The expansion plan summary from EGEAS for the 90 MW "Bradley Lake Project with Susitna" case is shown in Table 12.4-14. 12.4. 2 Sensitivity Studies It is recognized that uncertainty exists in the projections for future Railbelt electric loads, primarily because of the volatile nature of world oil prices. If the Railbelt load growth were to exceed the Reference Case projection, then Bradley Lake would continue to be an economically beneficial option for the Railbel t. However, in order to determine the impact on Bradley Lake if the Railbelt growth is less than the Reference Case, two other scenarios were examined with EGEAS. A load growth rate of zero percent per year was assumed to determine the economic performance of Bradley Lake under a Railbel t no-growth scenario. The 1983 Railbelt load was assumed constant for the duration of the power study. The fossil fuel prices were the same as in the Reference Case. The results of the sensitivity study are shown in Table 12.4-15. The present worth costs indicate that Bradley Lake remains competitive with a thermal plant base case for all three Bradley Lake capacities. For the zero load growth rate, the 60 HW Bradley Lake Project provides the largest net 12-20 benefit since the 230 kV Anchorage-Soldotna transmission line was required for the 90 and 135 MW cases to allow economy interchange and reserve sharing between the Kenai Peninsula and Anchorage. The cost for this line was greater than any additional savings due to either the 90 or 135 MW capacities. Tables 12.4-16 and 12.4-17 show the generation installation schedule developed by EGEAS for the base case and 90 MW Bradley Project under zero percent load growth. The generation by fuel class for the 1988 through 2007 study period is shown for these two cases in Tables 12.4-18 and 12.4-19. Lastly, the summaries of annual and present worth costs are shown in Tables 12.4-20 and 12.4-21 for the expansion plan with new thermal plants only and the plan including the 90 MW Bradley Lake Project. The second sensitivity study, performed at the request of the Alaska Power Authority, used the July 1983 "DOR 50% Case" load growth and fuel price projections which were described previous~y. Only two expansion plans were generated with EGEAS for this study: A base case (new thermal plants only) and a case with the 90MW Bradley Lake Project plus thermal plants. The results are as follows: Present Worth Cost ---Millions 1983 Dollars Thermal Plants* 90 MW Bradley Lake + Thermal Plants 3461 3305 >':Includes 230kV Anchorage-Soldotna transmission line. The installation of the 90 MW Bradley Lake Project results in a present worth savings of about $156 million. This savings is comprised of approximately $56 million for spinning reserve and energy cost savings plus $100 million for not installing the 230 kV Anchorage-Soldotna transmission line. For the DOR 50% case, this line is not required if the 90 MW Bradley Lake Project is installed on the Kenai Peninsula. A comparison of life cycle levelized bus-bar costs for Bradley Lake and thermal generation 12-21 alternates is shown in Figure 12.4-2 for the "DOR 50% Case." The 90 MW Bradley Lake Project has a slight energy cost advantage when compared to the 200 MW natural gas-fired combined cycle plant at the same capacity factor. Tables 12.4-22 to 12.4-27 contain further information from the EGEAS evaluations for the "DOR 50% Case." The plant installation schedules for the base case and 90 MW Bradley Lake case are shown in Tables 12.4-22 and 12.4-23. The corresponding annual values for energy generation and cost by fuel class for 1988 through 2007 are summarized in Tables 12.4-24 and 12.4-25. As for the Reference Case, the major Railbel t fuel source is natural gas, with combined cycle plants being the primary generation method with a smaller installed capacity of gas turbines. However, since the "DOR 50% Case" projects the price of coal as a constant value and the price of natural gas decreasing in real terms, the optimum expansion plans developed by EGEAS do not include the addition of any coal plants during the period of the power study. The summaries of annual costs for the two "DOR 50% Case" expansion plans are included in Tables 12.4-26 and 12.4-27. 12.4.3 Evaluation of Selected 90 MW Bradley Lake Project The power study results described in the previous sections were based on the Bradley Lake Project designs developed during the SWEC feasibility studies. After the selection by SWEC of the 90 MW Bradley Lake Project as the recommended option, additional refinements of the 90 MW plant were undertaken. As a result, small changes were made in the capital cost and annual average energy output from the 90 MW plant. The cost used for the economic analysis of the selected 90MW plant is the $283,019,000 overnight cost plus an additional $16,981,000 for interest during construction at the discount rate, for a total of $300,000,000. The original feasibility stage values and refined values for the selected plant are shown in Table 12.4-28. These changes to the 90 MW Bradley Lake Project resulted from the following: 12-22 1. A detailed review of the feasibility stage cost estimate, 2. Detailed evaluations of reservoir inflow conditions, and 3. Reevaluation of minimum diversion flows for aquatic habitat. EGEAS was run for the selected 90 MW Bradley Lake Project plus thermal plants (at the Reference Case load and fossil fuel price projections) to test the effect of the changes in capital cost and energy on the generation expansion plan. The present worth costs are shown in Table 12.4-29 along with the values from the base case for comparison. The present worth cost for the feasibility stage 90 MW Bradley Lake Plant was $5,464 million, or only $9 million higher than the selected plant present worth value. The lower present worth cost for the selected plant indicates that the increase in capital cost is more than offset by benefits from the additional average annual energy generated. Table 12.4-30 is a summary of the annual costs and present worth cost from EGEAS for the selected 90 MW Bradley Lake Project. As before, significant life-cycle savings result by using the refined 90 MW Bradley Lake Project in place of thermal generation alternatives for the Railbelt. The generation expansion plan developed by EGEAS for the selected plant is identical to the feasibility stage plan in Table 12.4-6. Figure 12.4-3 shows the levelized bus-bar cost for the selected 90 MW plant and the thermal alternatives. Although the 60 MW and 135 MW Bradley Lake Projects were not reevaluated after the feasibility stage, similar results would be obtained for these plant capacities. The cost and annual average energy values would change in the same proportion as for the selected 90 MW Plant. The three Bradley Lake plant capacities would have the same relative economic performance as discussed in the previous sections. Thus, the conclusions reached in the power study remain unchanged, and the 90 MW Bradley Lake Project is the recommended capacity. 12-23 POWER STUDIES AND ECONOMIC EVALUATION REFERENCES 1. Electric Power Research Institute, "Electric Generation Expansion Analysis System," Report No. EPRI EL-2561, Six Volumes. 2. Alaska Power Authority, Susitna Hydroelectric Project FERC Application, prepared by Harza-Ebasco Susitna Joint Venture, July 1983. 3. Alaska Power Authority, "FY83 Guidelines for Power Studies and Economic Analyses," July 1982. 4. Burns & McDonnell, "Report on the Power Requirements Study for Chugach Electric Association, Inc.," Report No. 82-182-4-001, 1983. 5. Battelle Pacific Northwest Laboratories, "Railbelt Electric Power Alternatives Study: Evaluation of Railbel t Electric Energy Plans," for the Office of the Governor, State of Alaska, Division of PoJicy Development and Planning and the Governor's Policy Review Committee, February 1982. 12-24 ECONOMIC EVALUATION PARAMETERS PARAMETER Inflation Rate Real Discount Rate Equipment Economic Lifetimes (years) Gas Turbines Combined Cycle Turbines Steam Turbines Hydroelectric Projects Transmission Systems Base Year Planning Period (20 years) Wood Poles Steel Towers Submarine Gables Economic Analysis Period (50 years) VALUE O% 3.5% 20 30 30 50 30 40 30 1983 1988-2007 1988-2037 '-------------TABLE 12.3-1 SHERMAN H. CLARK NSD CASE FORECAST SUMMARY OF INPUT AND OUTPUT DATA ITEM DESCRIPTION 1983 1985 1990 1995 World Oil Price (1983$/bbl) 28.95 26.30 27.90 32.34 Energy Price Used by RED (1980$) Heating Fuel Oil -Anchorage ($/MMBTU) 7.75 6.45 6.84 7.93 Natural Gas -Anchora~e ($/MMBTU) 1.73 1.95 2.88 4.05 State Petroleum Revenues<l (Nom.$xlo6J Production Taxes 1,474 1,561 2,032 1,868 Royalty Fees (Nom. $xl06) 1,457 1,555 2,480 2,651 State Gen. Fund Expenditures 3,288 3, 700 5,577 7 '729 State Population 457,836 490,146 554,634 608,810 State Employment 24 3, 067 258' 396 293,689 313,954 Railbelt Population 319,767 341,613 389,026 423,460 Rai1belt Employment 159,147 169,197 190,883 204,668 Railbelt Total Number of Households 111' 549 120,140 138, 640 152,463 Railbelt Electricity Consumption (GWh) Anchorage 2' 322 2,561 3,045 3, 371 Fairbanks 481 535 691 800 -- Total 2,803 3,096 3, 736 4,171 Railbelt Peak Demand (MW) 579 639 777 868 2000 2005 2010 37-50 43.47_ 50.39 9.19 10.65 . 12.35 4.29 4.96 5.38 1,910 2,150 2,421 3,078 3,799 4,689 9,714 13,035 • 17,975 644,111 686,663. 744,418 325,186 345' 701 376,169 451,561 486,851 533,218 214,542 231,584' 255,974 163,913 177' 849 195,652 3,662 4,107 4 '735 880 ~ 1,123 4,542 5,093· 5,858 945 1,059 1,217 lpetroleum revenues also include corporate income taxes, oil and gas property taxes, lease bonuses, and federal shared royalties. Source: Reference 2, Exhibit B, Table B.l03. ~----------------------------~--~------------~----TABLE12.3-2~ Year 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 PROJECTED PEAK AND ENERGY DEMAND (NET) SHERMAN H. CLARK NSD CASE Anchorage-Fairbanks- Cook Inlet Area Tanana Valley Area Total Rail belt Energy Peak Energy Peak Energy Peak GWh MW GWh MW GWh MW 2,322 469 481 110 2,803 579 2,442 493 508 116 2,950 609 2,561 517 535 122 3,096 639 2,658 538 566 129 3,224 667 2,755 558 597 136 3,352 695 2,852 579 629 144 3,481 722 2,949 599 660 151 3,609 750 3,045 619 691 158 3,737 777 3,111 633 713 163 3,824 796 3,176 646 735 168 3,911 814 3,240 659 757 173 3,997 832 3,306 672 778 178 4,084 850 3,371 686 800 183 4,171 868 3,429 697 816 186 4,245 884 3,487 709 832 190 4' 319 899 3,545 721 848 194 4,394 914 3,604 732 864 197 4,468 930 3,662 744 880 201 4,542 945 3, 751 762 902 206 4,652 968 3,840 780 923 211 4,762 991 3,929 798 944 215 4,872 1,013 4,018 816 965 220 4,983 1,036 4,107 834 986 225 5,09 3 1,059 4,232 859 1,013 231 5,246 1,091 4, 358 885 1,041 238 5,399 1,122 4,484 910 1,068 244 5,552 1,154 4,609 936 1,096 250 5,705 1,186 4, 735 961 1,123 256 5,858 1,217 Source: Reference 2, Exhibit B, Table 8.117 • ._____ _________ TABLE 12.3-3 Year 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 RAILBELT PEAK DEMAND AND ENERGY PROJECTION (NET) SHERMAN H. CLARK NSD CASE Peak Demand MW Change, %* 579 5.18 609 4.9 3 639 4.38 667 4.20 695 3.88 722 3.88 750 3.60 777 2.45 796 2.26 814 2.21 832 2.16 850 2.12 868 1.84 884 l. 70 899 1.67 914 1.75 930 1.61 945 2.4 3 968 2.38 991 2.22 1,013 2.27 1,036 2.22 1,059 3.02 1,091 2.84 1,122 2.85 1,154 2.77 1,186 2.61 1,217 Average annual compound growth rate: 2.8% Average load factor: 55% *Percent change from current to following year • Energy GWH 2,803 2,950 3,096 3,224 3,352 3,481 3,609 3, 737 3,824 3,911 3,997 4,084 4,171 4,245 4' 319 4,394 4,468 4,542 4,652 4,762 4,872 4,983 5,093 5,246 5,399 5,552 5,705 5,858 ..___ ________ TABLE 12.3-4 HISTORICAL ANCHORAGE AND COOK INLET PEAK DEMAND Peak Demandz MW Load Fraction Chugachl AMLP4 Occurring in Year HEA+KCL2 Seward3 Kenai Peninsula5 1974 185.6 24.7 5.8 76.8 0.12 1976 217.6 34.8 4.1 91.2 0.13 1978 290.1 50.6 7.0 94.5 0.15 1980 337.4 58.5 5.0 121.0 0.14 1982 372.3 66.9 5.3 ll8.5 0.15 1. Includes Chugach Electric Association, Homer Electric Association (HEA) and Kenai City Light (KCL), Matanuska and Seward. Source: Reference 4. 2. Reference 4. 3. Reference 4. 4. Data obtained from Anchorage Municipal Light and Power (AMLP), July 29, 1983. 5. HEA + KCL + Seward Chugach + AMLP .._____ _________ TABLE 12.3-5 HISTORICAL ANCHORAGE AND COOK INLET ENERGY REQUIREMENTS Ener~~ Reguirement 1 GWH Load Fraction Chugach 1 HEA+KCL2 Seward3 AMLP4 Occurring in Year Kenai Peninsula5 1974 708.4 124.8 16.0 391.7 0.13 1976 1,091.0 174.9 19.2 444.9 0.13 1978 1,351.0 240.0 23.2 443.1 0.15 1980 1,491.8 284.6 26.0 486.6 0.16 1982 1,765.2 346.5 29.5 579.5 0.16 1. Includes Chugach Electric Association, Homer Electric Association (HEA) and Kenai City Light (KCL), Matanuska and Seward. Source: Reference 4. 2. Reference 4. 3. Reference 4. 4. Reference 2, Exhibit B, Table B.86 except 1974 value which was obtained from Anchorage Municipal Light and Power (AMLP) data. 5. HEA + KCL + Seward Chugach + AMLP .____ ________ TABLE 12.3-6 Year 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2001 2008 2009 2010 LOAD PROJECTION (NET) SHERMAN H. CLARK NSD CASE SEPARATION OF ANCHORAGE -COOK INLET LOAD INTO ANCHORAGE AND KENAI PENINSULA Anchorase Kenai Peninsula Energy-GWH Demand-MW Energy-GWH Demand-MW 1,974 399 348 70 2,076 .419 366 74 2,177 439 384 78 2,259 457 399 81 2, 342 474 413 84 2,424 492 428 87 2,507 509 442 90 2,588 526 457 93 2,644 538 467 95 2,100 549 476 97 2,754 560 486 99 2,810 571 496 101 2,865 583 506 103 2,915 592 514 105 2,964 603 523 106 3,013 613 532 108 3,063 622 541 llO 3,113 632 549 112 3,188 648 563 ll4 3,264 663 576 117 3,340 678 589 120 3,415 694 603 122 3,491 709 616 125 3,597 730 635 129 3,704 752 654 133 3,8ll 774 673 137 3,918 796 691 . 140 4,025 817 710 144 ..____ _________ TABLE 12.3-7 Sheet 1 of 2 FUEL PRICE PROJECTIONS SHERMAN H. CLARK NSD SCENARIO 1983 $/MMBTU Natural Diesel Turbine Beluga Nenana Year Gas* Oil Oil Coal Coal 1983 2.17 6.87 6.23 1.86 1.72 1984 2.57 6.55 5.94 1.89 1.74 1985 2.46 6.25 5.66 1.92 1.77 1986 2.81 6.25 5.66 1.95 1.83 1987 2.81 6.25 5.66 1.98 1.83 1988 2.89 6.25 5.66 2.01 1.92 1989 2.96 6.4 3 5.83 2.05 1.97 1990 3.04 6.63 6.01 2.08 2.02 1991 3-13 6.83 6.19 2.11 2.07 1992 3.21 7.03 6-38 2.15 2.11 . 1993 3-30 7.24 6.57 2.18 2.17 1994 3-39 7.46 6.76 2.21 2.22 1995 3.48 7.68 6.97 2.25 2.27 1996 3-57 7-91 7.18 2.29 2. 32 1997 3.67 8.15 7.39 2.32 2.38 1998 3-77 8-39 7.61 2-36 2.43 1999 3.88 8.64 7.84 2.40 2.48 2000 3-99 8.91 8.08 2.44 2.55 2001 4.10 9.18 8.32 2.48 2.60 2002 4.21 9.45 8.57 2.51 2.66 2003 4.33 g. 74 8.83 2.55 2.73 2004 4.45 10.03 9.09 2.60 2.79 2005 4.57 10.32 9.36 2.64 2.85 2006 4.70 10.63 9.64 2.68 2.9 3 2007 4.83 10.95 9.9 3 2.72 2.99 2008 4.97 11.28 10.23 2.77 3.06 2009 5.11 11.62 10.54 2.81 3.14 2010 5.25 11.97 10.85 2.86 3.21 2011 5.38 12.26 11.31 2.90 3.28 2012 5.50 12.57 11.40 2.95 3-35 2013 5.63 12.88 11.69 2.99 3.4 3 2014 5.77 13.21 11.98 3.04 3-51 2015 5.90 13.54 12.28 3.09 3.58 2016 6.04 13.88 12.59 3.14 3.66 2017 6.19 14.22 12.90 3.19 3. 75 2018 6-34 14.58 13.23 3.24 3-83 2019 6.49 14.94 13.56 3.29 3-91 2020 6.64 15.32 13.89 3-35 4.00 '-----------TABLE 12.3-8 Year- 2021 2022 2023 2024 2025 2026 2027 2028 2029 ' 2030 2031 2032 2033 2034 2035 2036 2037 Sheet 2 of 2 FUEL PRICE PROJECTIONS SHERMAN H. CLARK NSD SCENARIO 1983 $/MMBTU Natural Diesel Turbine Beluga Nenana Gas* Oil Oil Coal Coal 6.74 15.55 14.10 3.40 4.09 6.83 15.78 14.31 3.45 4.18 6.93 16.02 14.5 3 3-51 4.28 7 .o 3 16.26 14.75 3-57 4-37 7.13 16.50 14.97 3.62 4.47 7.23 16.75 15.19 3.68 4.57 7.34 17.00 15.42 3. 74 4.67 7.44 17.25 15.65 3.80 4.77 7.55 17.51 15.89 3.86 4.88 7.66 17.78 16.13 3.92 4.99 7. 7 3 17.95 16.29 3.98 5.10 7.81 18.13 16.45 4.05 5.21 7.88 18.31 16.61 4.11 5-33 7.96 18.50 16.78 4.18 5.45 8.03 18.68 16.95 4.25 5.57 8.11 18.87 17.12 4. 31 5.70 8.19 19.06 17.29 4.38 5.82 * Includes 30¢/MMBTU for pipeline transportation cost. Source: Reference 2, Exhibit D, Appendix D-1, Table D-1.9 (natural gas), Table D-2.14 (Beluga coal and Nenana coal), and Table D-3.2 (diesel oil and turbine oil) • .___ ________ TABLE 12.3-8 TOTAL GENERATING CAPACITY WITHIN THE RAILBELT SYSTEM --1982 Abbrevia-Installed tions Railbelt Utility Capacity (l) AMLP Anchorage Municipal Light and Power Department 311.6 CEA Chugach Electric Association 463.5 GVEA Golden Valley Electric Association 221.6 FMUS Fairbanks Municipal Utilities System 68.5 MEA Matanuska Electric Association 0.9 HEA Homer Electric Association 2.6 SES Seward Electric System 5.5 APAd Alaska Power Administration 30.0 U of A University of Alaska 18.6 Total 1,122.8(2) (1) Installed capacity as of 1982 at 0°F. (2) Excludes National Defense installed capacity of 101.3 MW. Source: Reference 2, Exhibit D, Table D.l3. "------------TABLE 12.3-9 (SHEET 1 of 5) EXISTING GENERATING PLANTS IN THE RAILBELT Plant/Unit EklutnaCa) Station nCb) Unit fFl Unit 112 Unit 113 Unit /14 Diesel l(c) Diesel 2Cc) Station n(d) Unit /15 Unit 116 Unit 117 Unit /18 Beluga Unit fFl Unit 112 Unit 113 Unit /J4(e) Unit /15 Unit #6 Unit 117 Unit /J8(f) Prime Mover H SCCT SCCT SCCT SCCT D D SCCT CCST SCCT SCCT SCCT SCCT RCCT SCCT RCCT CCCT CCCT CCST Fuel ~ Date Nameplate Capacity (MW) ALASKA POWER ADMINISTRATION 1955 30.00 Generating Capacity @ 0°F (MW) ANCHORAGE MUNICIPAL LIGHT AND POWER NG/0 1962 14.00 16.3 NG/0 1964 14.00 16.3 NG/0 1968 18.00 18.0 NG/0 1972 28.50 32.0 0 1962 1.10 1.1 0 1962 1.10 1.1 0 1974 32.30 40.0 1979 33.00 33.0 0 1980 73.60 90.0 NG/0 1982 73.60 90.0 CHUGACH ELECTRIC ASSOCIATION NG 1968 15.25 16.1 NG 1968 15.25 16.1 NG 1973 53.30 53.0 NG 1976 10.00 10.7 NG 1975 58.50 58.0 NG 1976 72.90 68.0 NG 1977 72.90 68.0 NG 1982 55.00 42.0 Heat Rate (BTU/kWh) 14,000 14,000 14,000 12,500 10,500 10,500 12,500 11,000 12,500 15,000 15,000 10,000 15,000 10,000 15,000 15,000 '-------------TABLE 12.3-10 (SHEET 2 of 5) EXISTING GENERATING PLANTS IN THE RAILBELT Nameplate Generating Prime Fuel Capacity Capacity Heat Rate Plant/Unit Mover ~ Date (MW) @ 0°F (MW) (BTU/kWh) CHUGACH ELECTRIC ASSOCIATION (continued) CooEer Lake (g) Units tn, 2 H 1961 15.0 16.0 International Unit tn SCCT NG 1964 14.0 14.0 15,000 Unit li2 SCCT NG 1965 14.0 14.0 15,000 Unit 113 SCCT NG 1970 18.5 18.0 15,000 Bernice Lake Unit tn SCCT NG 1963 7.5 8.6 23,400 Unit 112 SCCT NG 1972 16.5 18.9 2 3,400 Unit 113 SCCT NG 1978 23.0 26.4 23,400 Unit 114 SCCT NG 1982 23.0 26.4 12,000 Knik Arm(h) Unit In ST NG 1952 0.5 0.5 Unit 112 ST NG 1952 3.0 3.0 Unit 113 ST NG 1957 3.0 3.0 Unit 114 ST NG 1957 3.0 3.0 Unit t/5 ST NG 1957 5.0 5.0 HOMER ELECTRIC ASSOCIATION Kenai Unit Ill D 0 1979 0.9 o.9 15,000 Point Graham Unit n D 0 1971 0.2 0.2 15,000 Seldovia Unit Ill D 0 1952 0.3 0.3 15,000 Unit n D 0 1964 0.6 0.6 15,000 Unit 113 D 0 1970 0.6 0.6 15,000 .____ _________ TABLE 12.3-10 (SHEET 3 of 5) EXISTING GENERATING PLANTS IN THE RAILBELT Nameplate Generating Prime Fuel Capacity Capacity Heat Rate Plant/Unit Mover ~ Date (MW) @ 0°F (MW) (BTU/kWh) MATANUSKA ELECTRIC ASSOCIATION Talkeetna Unit til D 0 1967 0.9 0.9 15,000 SEWARD ELECTRIC SYSTEM SES ( j) Unit Ill D 0 1965 1.5 1.5 15,000 Unit li2 D 0 1965 1.5 1.5 15,000 Unit ti3 D 0 1965 2.5 2.5 15,000 MILITARY INSTALLATIONS --ANCHORAGE AREA Elmendorf AFB Total Diesel D 0 1952 2.1 10,500 Total ST ST NG 1952 31.5 12,000 Fort Richardson Total Diesel(c) D 0 1952 7.2 10,500 Total ST(i) ST NG 1952 18.0 20,000 GOLDEN VALLEY ELECTRIC ASSOCIATION Healy Coal ST Coal 1967 64.7 65.0 13,200 Diesel(c) D 0 1967 64.7 65.0 10,500 North Pole Unit Ill SCCT 0 1976 64.7 65.0 14,000 Unit t/2 SCCT 0 1977 64.7 65.0 14,000 Zendher GTl SCCT 0 1971 18.4 18.4 15,000 GT2 SCCT 0 1972 17.4 17.4 15,000 GT3 SCCT 0 1975 2.8 3.5 15,000 GT4 SCCT 0 1975 2.8 3.5 15,000 Combined Diesel D 0 1960-70 21.0 21.0 10,500 .____ ________ TABLE 12.3-10 (SHEET 4 of 5) EXISTING GENERATING PLANTS IN THE RAILBELT Nameplate Generating Prime Fuel Capacity Capacity Heat Rate Plant/Unit Mover ~ Date (MW) @ 0°F (MW) (BTU/kWh) UNIVERSITY OF ALASKA --FAIRBANKS Sl ST Coal 1.50 1.50 12,000 S2 ST Coal 1980 1.50 1.50 12,000 S3 ST Coal 10.00 10.00 12,000 Dl D 0 2.80 2.80 10,500 D2 D 0 2.80 2.80 20,500 FAIRBANKS MUNICIPAL UTILITIES SYSTEM Chena Unit ill ST Coal 1954 5.00 5.00 18,000 Unit 1/2 ST Coal 1952 2.50 2.50 22,000 Unit fF3 ST Coal 1952 1.50 1.50 22,000 Unit #4 SCCT 0 1963 5.30 7.00 15,000 Unit #5 ST Coal 1970 21.00 21.00 13,320 Unit 116 SCCT 0 1976 23.10 28.80 15,000 Diesel fFl D 0 1967 2.80 2.80 12,150 Diesel #2 D 0 1968 2.80 2.80 12,150 Diesel fF3 D 0 1968 2.80 2.80 12,150 MILITARY INSTALLATIONS --FAIRBANKS Eielson AFB Sl, S2 ST 0 1953 2.50 S3, S4 ST 0 1953 6.25 Fort Greelel • Dl D2 ~3(i) D 0 3.00 10,500 D4: D5 t i D 0 2.50 10,500 Fort Wainwri~ht ( j) Sl, S2, S3, S4 ST Coal 1953 20.00 20,000 S5(i) ST Coal 1953 2.00 '--------------TABLE 12.3-10 (SHEET 5 of 5) EXISTING GENERATING PLANTS IN THE RAILBELT Legend: Notes: --- H D SCCT RCCT ST CCCT NG 0 Hydro. Diesel. Simple cycle combustion turbine. Regenerative cycle combustion turbine. Steam turbine. Combined cycle combustion turbine. Natural gas. Distillate fuel oil. (a) Average annual energy production for Eklutna is approximate- ly 148 GWh. (b) All AMLP SCCT's are equipped to burn natural gas or oil. In normal operation they are supplied with natural gas. All units have reserve oil storage for operation in the event gas is not available. (c) These are black-start units only. They are not included in total capacity. (d) Units #5, 6, and 1 are designed to operate as a combined cycle plant. When operated in this mode, they have a generating capacity at 0°F of approximately 139 MW with a heat rate of 8,500 BTU/kWh. (e) Jet engine, not included in total capacity. (f) Beluga Units #6, 1, and 8 operate as a combined cycle plant. When operated in this mode, they have a generating capacity of about 178 MW with a heat rate of 8,500 BTU/kWh. (g) Average annual energy production for Cooper Lake is approxi- mately 42 GWh. (h) Knik Arm units are old and have higher heat rates; they are not included in total. (i) Standby units. (j) Cogeneration used for steam heating. Source: Reference 2, Exhibit B, Table B.73 • .....__---------TABLE 12.3-10 THERMAL GENERATION PLANT PARAMETERS 1983 DOLLARS*** Capital Fixed Variable Forced Cost* O&M O&M Outages Heat Rate $/K\v $/KW-YR $/MWH % BTU/KWH Years Combined C;z:cle 200 MW 1,185 7.76 1.81 8.0 8,000 Gas Turbine 70 MW 683 2.89 5.18 8.0 12,200 Coal** 200 MW 2,632 18.01 0.64 5.7 10,000 * Includes IDC at the rate of 3.5 percent per year. ** Includes transmission cost. *** 1982 dollars were escalated to 1983 dollars by 7 percent. Source: Reference 2, Exhibit D, Table D.l8. Construe-Life- tion Period time Years Years -- 2 30 l 20 6 30 '"-------------------------TABLE 12.3-11 NEW HYDROELECTRIC GENERATION ALTERNATIVES PLANT PARAMETERS Projected Hy droel ec tri c Capacity Average Annual Installation Plant MW Energy, GWH Year Bradley Lake 60 330.5 1988 Bradley Lake 90 345.4 1988 Bradley Lake 135 356.6 1988 Wa tana* 1,020 3,499.0 1993 Devil Canyon* 600 3,435.0 2002 *Source: Reference 2, Exhibit B, page B-3-11. ------------TABLE 12.3-12 BRADLEY LAKE HYDROELECTRIC PROJECT PLANT COSTS Millions 1983 Dollars Bradley Lake Capacity, MW Capital Cost* Annual Fixed O&M** * ** *** 60 90 135*** Includes IDC. 275.70 287.95 303.50 1.252 1.252 1.252 Includes cost of annual capital renewals (i.e., sinking fund for periodic major equipment replacement). Excludes cost of 230 kV Anchorage/Soldotna transmission line. NOTE: For description of Capital Costs and Annual Fixed O&M Cost, see Section 11 of this report. L..----------TABLE 12.3-13 Watana SUSITNA HYDROELECTRIC PROJECT PLANT COSTS Millions 1982 Dollars* ~-~-Annual Annual Capital Cost** Fixed O&M Capital Renewals 4081 10.4 10.79 Devil Canyon 1734 4.8 4.66 * 1982 dollars were escalated to 1983 dollars by 7% for the economic analysis. ** Includes AFUDC. Source: Reference 2, Exhibit D, Table D.l, Table D.5 and Table D.l2. ~---------TABLE 12.3-14 Year 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 RAILBELT PEAK DEMAND AND ENERGY PROJECTION (NET) DOR 50% SCENARIO (JULY 1983) Peak Demand MW Change, %* 580 5-34 611 4.91 641 3.12 661 3.18 682 2.93 702 2.99 723 2.77 743 1.35 753 1. 33 763 1.18 772 1.30 782 1.28 792 1.64 805 1.61 818 1.59 831 1.56 844 1.54 857 2.10 875 2.06 893 1.90 910 1.98 928 1.94 946 2.64 971 2.57 996 2.41 1,020 2.45 1,045 2.39 1,070 Average annual compound growth rate: 2.3% Average load factor: 55% *Percent change from current to following year. Source: Alaska Power Authority Energy GWH 2,808 2,956 3,104 3,198 3,292 3,385 3,479 3,573 3,620 3,667 3,714 3, 761 3,808 3,871 3,9 35 3,998 4,062 4,125 4,211 4,297 4,384 4,470 4,556 4,676 4,796 4,916 5,036 5,156 L------------TABLE 12.3-15 Year 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000** FUEL PRICE PROJECTIONS DOR 50% SCENARIO (JULY 1983) 1983 $/MMBTU Natural Turbine Gas* Oil 2.77 6.23 2.60 5.80 2.4 3 5. 37 2.47 5-30 2.51 5.23 2.54 5.16 2.58 5.09 2.62 5.02 2.60 4.98 2.58 4.95 2.57 4.91 2.55 4.88 2.53 4.84 2.52 4.81 2.50 4.77 2.49 4.74 2.47 4.70 2.46 4.67 Coal 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 1.80 * Includes 30¢/MMBTU for pipeline transportation cost. ** All fuel prices remain constant after the year 2000. Source: Alaska Power Authority ~--------TABLE 12.3-16 LEVELIZED FUEL COSTS (1988-2037) $/MMBTU Natural Gas Coal Sherman Clark NSD Case 4.77 2. 7 3 DOR 50% Case (July 1983) 2.50 1.80 '-----------TABLE 12.3-17 ALTERNATIVES TO BRADLEY LAKE PRESENT WORTH COST OF OPTIMUM EXPANSION PLANS ALTERNATIVE 0 Thermal without hydroelectric (combined cycle, gas turbines, coal) -with Anchorage/Soldotna 230 KV Tie -without Anchorage/Soldotna 230 KV Tie 0 Susitna and Thermal -with Anchorage/Soldotna 230 KV Tie PRESENT WORTH COST MILLIONS OF 1983 DOLLARS 5,832 5,860 5,724 '-----------TABLE 12.4-1 BRADLEY LAKE WITHOUT SUSITNA PRESENT WORTH COSTS AND SAVINGS FOR DIFFERENT BRADLEY LAKE CAPACITIES TOTAL RAILBELT EXPANSION PLANS BRADLEY LAKE ANCHORAGE/SOLDOTNA PRESENT WORTH, MILLIONS 1983 $ TOTAL COST SAVINGS DUE TO BRADLEY LAKE SAVINGS COMPARED TO RAILBELT BASE CASE, % CAPACITY, MW 230 KV TIE 60 NO 5,517 315 5.4 90 NO 5,464 368 6.3 135 YES 5,535 297 5.1 Railbelt Base Case Present Worth Cost = $5,832 (Millions 1983 $) --------------TABLE 12.4-2 BRADLEY LAKE WITHOUT SUSITNA PRESENT WORTH COSTS AND SAVINGS FOR DIFFERENT BRADLEY LAKE CAPACITIES KENAI PENINSULA EXPANSION PLANS BRADLEY LAKE ANCHORAGE/SOLDOTNA PRESENT WORTH, MILLIONS 1983 $ TOTAL COST SAVINGS DUE TO BRADLEY LAKE CAPACITY, MW 230 KV TIE 60 NO 605 299 90 NO 599 305 135 YES 695 209 Kenai Peninsula Base Case Present Worth Cost = $904 (Millions 1983 $) SAVINGS COMPARED TO KENAI PENIN. BASE CASE I % 33.1 33.7 23.1 '------------TABLE 12.4-3 Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Total NEW GENERATION CAPACITY ADDED BASE CASE (THERMAL PLANTS ONLY) SHERMAN H. CLARK NSD CASE Combined Cycle Coal Gas Turbine 200 MW 200 MW 70 MW IF Capacity tF Capacity IF Capacity Units MW Units MW Units MW 1.0 200 1.0 200 1.0 200 1.0 200 1.0 70 1.0 200 1.0 200 1.0 200 4.0 800 3.0 6oo 1.0 70 '------------TABLE 12.4-4 Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Total NEW GENERATION CAPACITY ADDED 60 MW BRADLEY LAKE PROJECT SHERMAN H. CLARK NSD CASE Hydroelectric Combined Cycle Coal 200 MW 200 MW II Capacity II Capacity # Capacity Gas Turbine 70 MW II Capacity Units MW Units MW Units MW Units MW 1.0 60 1.0 200 1.0 200 1.0 200 1.0 70 1.0 70 1.0 70 1.0 200 1.0 200 1.0 200 1.0 60 3.0 600 3.0 600 3.0 210 .____ ________ TABLE 12.4-5 Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Total NEW GENERATION CAPACITY ADDED 90 MW BRADLEY LAKE PROJECT SHERMAN H. CLARK NSD CASE Hydroelectric Combined Cycle Coal 200 MW 200 MW II Capacity II Capacity II Capacity Gas Turbine 70 MW II Capacity Units MW Units MW Units MW Units MW 1.0 90 1.0 200 1.0 200 1.0 200 l.O 70 l.O 70 l.O 200 l.O 200 1.0 200 1.0 90 3.0 600 3.0 600 2.0 140 .____ ________ TABLE 12.4-6 Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Total NEW GENERATION CAPACITY ADDED 135 MW BRADLEY LAKE PROJECT SHERMAN H. CLARK NSD CASE Hy droel ec tric Combined Cycle Coal 200 MW 200 MW II Capacity II Capacity # Capacity Gas Turbine 70 MW // Capacity Units MW Units MW Units MW Units MW 1.0 135 1.0 200 1.0 200 1.0 70 1.0 200 1.0 70 1.0 200 1.0 200 1.0 200 1.0 135 3.0 600 3.0 600 2.0 140 ----------TABLE 12.4-7 Natural Gas Energy Fuel Cost Year GWH $106 1988 2,903 78 1989 3,032 84 1990 3,153 91 1991 3,237 97 1992 3, 303 102 1993 3,375 107 '1 AI"'\ II 3,652 1AI""\ .l.:;l:;l'i .I.V:;I 1995 3, 726 115 1996 3, 794 120 1997 4,288 135 1998 4, 342 140 1999 4,416 147 2000 4,616 154 2001 4, 731 163 2002 4,836 171 2003 4,947 180 2004 3,890 146 2005 3,005 117 2006 1,992 82 2007 2,131 90 *Gross Generation GENERATION BY FUEL CLASS BASE CASE (NEW THERMAL PLANTS ONLY) SHERMAN H. CLARK NSD CASE Existing Coal Oil H~droelectric Energy Fuel Cost Energy Fuel Cost Energy Fuel Cost GWH $106 GWH $10~-GWH $106 633 16 28 1 190 0 638 16 39 2 190 0 642 17 54 3 190 0 645 17 66 4 190 0 647 18 90 5 190 0 649 18 108 7 190 0 543 1C. 33 ,., 1{'\{'\ {'\ .I.U t::. .L"7V v 550 16 46 3 190 0 556 17 50 3 190 0 172 5 19 1 190 0 177 5 34 2 190 0 179 6 39 3 190 0 89 3 14 1 190 0 89 3 17 1 190 0 89 3 27 2 190 0 89 3 29 2 190 0 1,292 34 0 0 190 0 2,447 65 0 0 42 0 3,623 98 0 0 42 0 3,643 100 0 0 42 0 Total Railbelt Energy* Fuel Cost GWH $106 3,753 96 3,899 103 4,039 111 4,137 118 4,230 125 4, 322 132 " 111 Q 127 --r J "'1~V 4,511 134 4' 5.90 140 4,669 141 4, 7.43 148 4, 8'24 155 4,909 158 5 ,0,27 167 5,1J42 176 5, 2155 185 5, 372 180 5,493 182 5,657 180 5,816 189 '---------,------------,--------~-------------TABLE 12.4-8 GENERATION BY FUEL CLASS 90 MW BRADLEY LAKE PROJECT SHERMAN H. CLARK NSD CASE Natural Gas Coal Oil Hldroelectric* Energy Fuel Cost Energy Fuel Cost Energy Fuel Cost Year GWH $106 GWH $106 GWH 1988 2,498 73 675 17 44 1989 2, 710 70 642 17 11 1990 2,842 76 646 17 16 1991 2,934 82 648 18 21 1992 3,015 87 650 18 30 1993 3,099 {)') 652 , 0 38 :7"-.J..V 1994 3,170 97 650 19 61 1995 3,251 102 652 19 73 1996 3,479 104 562 17 18 1997 3,948 119 178 5 10 1998 4,017 124 180 6 16 1999 4,100 1~0 180 6 16 2000 4,258 139 89 3 24 2001 4,390 148 89 3 14 2002 4,511 157 89 3 13 2003 3,429 121 1,292 34 8 2004 3,547 129 1,292 34 0 2005 2,657 99 2,451 65 0 2006 1,635 63 3,638 98 0 2007 1, 773 71 3,656 100 0 * 90 MW Bradley Lake Project plus existing hydroelectric plants. ** Gross generation. $106 2 1 1 1 2 " t:. 4 5 1 1 1 1 2 1 1 1 0 0 0 0 Energy Fuel Cost GWH $106 535 0 535 0 535 0 535 0 535 0 .......... ::> .:;::> 0 535 0 535 0 535 0 535 0 535 0 535 n 535 0 535 0 535 0 535 0 535 0 387 0 387 0 387 0 Total Railbelt Energy** Fuel Cost GWH $106 3, 753 92 3,899 87 4,040 94 4,138 100 4,232 106 lo ,........,_ 113 "',j~:;> 4,418 120 4,511 126 4,594 122 4,672 125 4,748 130 4,831 137 4,906 144 5,029 152 5,148 160 5,264 155 5,375 163 5,496 164 5,660 161 5,817 171 L----------------"--------------TABLE 12.4-9 EXPANSION PLAN SUMMARY BASE CASE (THERMAL PLANTS) REFERENCE CASE LOAD ELECTRIC POHER RESEARCH INSTITUTE BRADLEY LAKE EGEAS REPORT VER 00 LEV 00 EXPAUSION PLAII SUI·ft!ARY *********MMMifMMMffMMiflflflfMMM*MMMMtiMMM*IfM*If*MMM************************************************M*IfMiflfMiflflf*MiflflflflflflfiltlflflflftflfM PLAN PEAH ENERGY •••••• CAPACITY, IIH ••••••• RESERVE ••.••••••• tlEH UNITS •••••••••• YEAR LOAD, IIH GIIH IIISTALLED RETIRED TOTAL PERCEUT CAPACITY ,IIH CAPITAL CDSTS,H$ --------------------------- BEliCH 780. 3757. 1079. 38.29 19e8 779. 375Q. 200. 6. 1~79. 6'1.01 zoo. 237. 1989 810. 3899. 0. 0. 1279. 57.95 0. 0. 1990 839. QO'IO. 0. 1. 1278. 52.39 o. 0. 1991 859. <1139. 0. 19. 1259. '16.58 0. 0. 1992 879. '1232. o. 31. 1228. 39.16 0. 0. 1993 898. QJ4:6. 0. 8. 1221. 35.91 o. o. 199Q 918. Q'l19. zoo. 28. 1393. 51.78 zoo. 237. 1995 937. '1513. 0. 20. 1373. '16.5'1 0. 0. 1996 95'1. Q596. 0. 88. 1285. 3Q.69 0. 0. 1997 970. '167'1. 200. 129. 1356. 39.71 200. 237. 1998 987. Q752. D. '19. 1307. 32.50 D. 0. 1999 100'1. '1835. D. 1. 1306. 30.13 D. D. 2000 1020. '1913. zoo. '15. H61. '13.26 200. 237. 2001 10'15. 5032. D. 0. 1'161. 39.86 D. 0. 2002 1070. 5152. 0. '15. 1Q16. 32.QO D. 0. 2003 1093. 5266. 70. 53. 1Q33. 31.05 70. '18. 2DOQ 1118. 5386. zoo. 139. 1'19'1. 33.61 zoo. 526. 2005 11'13. 5505. 200. 89. 1606. '10.'16 200. 526. 2006 1178. 5672. 200. 188. 1618. 37.36 200. 526. 2007 1211. 5833. 0. 0. 1618. 33.57 0. 0 • • • ALL UNITS •• • • • • • • • UEH UNITS DilLY ••••••• • •• ••••••••••••••••••••• COST SUiftiARY •••••••••••••••••••••••• YEAR PROD. COST FIXED 0 & H FIXED CHARGES ANNUAL CUll. AtlNUAL PRESENT l«lRTH CUll. PRES. HORTH ------------------------------·------------------------------------------- 1988 10Q. 2. 13. 118. 118. 100. 100. 1989 112. 2. 13. 126. ~45 .. 103. 202. 1990 120. 2. 11. 135. 379. 106. 308. 1991 128. 2. 13. 1QZ. 521. 108. Q16. 1992 135. 2. 13. 1Q9. 671. 110. 526. 1993 n1. z. 13. 157. 828. 112. 631. 199Q 136. 3. 26. 165. 993. 113. 750. 1995 1'13. 3. 26. 172. 1165. 11Q. 86'1. 1996 150. 3. 26. 178. 1H3. 11'1. 978. 1997 150. 5. 39. 193. 1536. 119. 1097. 1998 157. 5. 39. zoo. 1737. 119. 1217. 1999 16Q. 5. 39. 208. 19'1'1. 120. 1337. 2000 167. 6. 52. 225. Zl69. 125. 1'162. 2001 176. 6. 52. 23'1. 2'103. 126. 1588. 2002 185. 6. 52. 2'13. 26Q6. 126. 11n. 2003 195. 6. 55. 257. 2903. 129. 18Q3. 200'1 189. 10. 8'1. 282. 3105. 137. 1980. zoos 189. 1'1. 112. 315. 3500. 1'18. Zl28. 2006 186. 17. 1'11. 3'1'1. 38'1Q. 156. 228Q. 2007 196. 17. 1Ql. JSQ. '1198. 155. 2'139. EXT. 3293. 5732. tlOTES -AtltiUAL COSTS ARE Itl HILLIDtiS OF CURRENT DOLLARS. -PRESEtlT NORTH COSTS ARE IN IIILLiotiS OF DOLLARS DISCOUNTED TO THE BEGINNitiG OF 1983. TABLE 12.4-10 EXPANSION PLAN SUMMARY 90 MW BRADLEY LAKE PROJECT REFERENCE CASE LOAD ELECTRIC POHER RESEARCH IHSTlTUTE BRADLEY LAHE EGEAS REPORT VER 00 LEV 00 EXPANSiotl PLAN SutttiARY .................... ._. ......................................................................... ************************ PLAN PEAH En&5Y •••••• CAPACITY, HH ••••••• RESERVE •••••••••• NEH UNITS •••••••••• YEAR LOAD, HH 6HH INSTALLED RETIRED TOTAL PERCENT CAPACITY ,1-IH CAPITAL CDSTSotl$ --------------------------- BENCH 780. 3757. 1079. 38.Z9 1988 719. 3754. , .. 6. 1169. 49.96 90. Z88. 1989 810. 3899. 200. 0. 1369. 69.06 zoo. Z31. 1990 839. '10'10. 0. 1. 1368. 63.12 o. 0. 1991 859. '1139. 0. 19. 13'19. 57.05 o. 0. 1992 879. '1232. 0. 31. 1318. 50.01 o. 0. 1993 898. 43Z6. 0. 8. 1311. 45.93 o. 0. 1994 918. 4419. 0. Z8. 1Z83. 39.79 o. 0. 1995 937. 4513. 0. zo. 1Z63. 34.80 0. 0. 1996 954. 115"· zoo. 88. 1375. '14.1Z zoo. Z37. 1997 970. 46711. zoo. 1Z9. 14'16. 48.99 zoo. Z37. 1998 987. 475Z. 0. '19. 1397. 41.62 0. o. 1999 1004. 4835. o. 1. 1396. 39.10 0. 0. 2000 10ZO. 4913. 0. 45. 1351. 32.47 0. o. 2001 1045. 5032. 70. 0. 14Z1. 36.03 70. 48. zooz 1070. 515Z. 70. 45. 1446. 35.Zl 70. 48. Z003 1093. 5Z66. 200. 53. 1593. 45.69 zoo. 5Z6. C:OO'I 1116. 5386. o. 139. HS4. 30.03 0. o. Z005 1143. 5505. 200. 89. 1566. 36.96 zoo. 526. 2006 1176. 567Z. zoo. 188. 1578. 33.97 zoo. SZ6. Z007 1Z11. 5833. o. 0. 1578. 30.27 o. o. • • ALL UNITS •• ••••••• NEH UNITS OtL Y ••••••• • ••••••••••••••••••••••• COST SUHHARY •••••••••••••••••••••••• YEAR PROD. COST FIXED 0 t H FIXED CHARGES AHNUAL tUN. AHtllJAL PRESENT tlORTH CUtl. PRES. HORTH -------------------------------------------------------------------------- 1988 102. 1. 14. 117. 117. 99. 99. 1989 94. 3. 27. 124. 2'1Z. 101. 200. 1990 10Z. 3. Z1. 13Z. 37'1. 104. 304. 1991 108. 3. Z7. 138. 512. 105. 409. 1992 115. 3. Z7. 145. 657. 106. 515. 1993 12Z. 3. Z7. 15Z. 809. 108. 623. 199'1 1:!9. 3. Z7. 159. 968. 109. 73Z. 1995 136. 3. 27. 166. 1134. 110. 8'12. 1996 130. '1. '10. 17'1. 1309. 111. 953. 1997 133. 6. 53. 192. 1500. 118. 1072. 1998 139. 6. 53. 198. 1696. 118. 1189. 1999 1'15. 6. 53. ZO'I. 190Z. 116. 1307. 2000 153. 6. 53. Z12. Zl1'1. 118. 1425. 2001 161. 6. 56. ZZ'I. 2337. 1ZO. 1546. 200Z 170. 6. 60. Z36. 257'1. 123. 1669. Z003 163. 10. 88. Z61. Z835. Ill. 1800. 2004 172. 10. 88. 270. 3105. Ill. 1931. zoos 172. 14. 117. 302. 3407. 14Z. 2073. 2006 167. 17. 1'16. 330. 3738. 150. 2223. Z007 178. 11. 146. 340. '1078. 149. z:sn. EXT. 3089. 1'141. NOTES -ANNUAL COSTS ARE IN HILLIOIIS Of CURRENT DOLLARS. -PRESEIIT HORTH COSTS ARE IN lllLLIOHS OF DOLLARS DISCOUNTED TO THE BEGINNING Of 1983. TABLE 12.4-11 BRADLEY LAKE WITH SUSITNA PRESENT WORTH COSTS AND SAVINGS FOR DIFFERENT BRADLEY LAKE CAPACITIES TOTAL RAILBELT EXPANSION PLANS BRADLEY LAKE ANCHORAGE/SOLDOTNA PRESENT WORTH, MILLIONS 1983 $ TOTAL COST SAVINGS. DUE TO BRADLEY LAKE CAPACITY, MW 230 KV TIE 60 NO 5,548 176 90 NO 5,549 175 135 YES 5,658 66 Rai1be1t Base Case Present Worth Cost = $5,724 (Millions 1983 $) SAVINGS COMPARED TO RAILBELT BASE CASE I % 1.2 '-------------TABLE 12.4-12 BRADLEY LAKE WITH SUSITNA PRESENT WORTH COSTS AND SAVINGS FOR DIFFERENT BRADLEY LAKE CAPACITIES KENAI PENINSULA EXPANSION PLANS BRADLEY LAKE ANCHORAGE/SOLDOTNA PRESENT WORTH, MILLIONS 1983 $ TOTAL COST SAVINGS DUE TO BRADLEY LAKE CAPACITY, MW 230 KV TIE 60 NO 531 143 90 NO 523 151 135 YES 624 50 Kenai Peninsula Base Case Present Worth Cost = $674 (Millions 1983 $) SAVINGS COMPARED TO KENAI PEN IN. BASE CASE I % 21.2 22.4 7.4 ~-----------TABLE 12.4-13 EXPANSION PLAN SUMMARY 90 MW BRADLEY LAKE PROJECT WITH SUSITNA REFERENCE CASE LOAD ELECTRIC POHER RESEARCH INSTITUTE BRADLEY LAI<E EGEAS REPORT VER 00 LEV 00 EXPANSION PLAN SUIUfARY *******************~*************************************************************************************************** PLAtl PEAH ENERGY • • • • • • CAPACITY, tiH ••••••• RESERVE •••••••••. NEH UNITS •••••••••. YEAR LOAD, IIH GHH IllSTALLED RETIRED TOTAL PERCENT CAPACITY, tiH CAPITAL COSTS,If$ -------------------------- BEliCH 780. 3757. 1079. 38.29 1908 779. 37Sq. 90. 6. 1169. 49.96 90. 288. 1989 810. 3899. 0. o. 1169. 4'1.36 0. o. 1990 839. 40'10. o. 1. 1168. 39.27 0. o. 1991 859. 4139. o. 19. 1149. 33.78 0. 0. 1992 879. '1232. o. 31. 1118. 27.25 0. 0. 1993 898. '1326. 102D. a. 2131. 137.Z3 1020. 4367. 199'1 91S. 4419. D. ~e. 2103. 129.16 0. 0. 1995 937. 4513. D. 20. 2083. 122.32 o. D. 1996 95'1. 4596. 0. 88. 1995. 1D9 .10 0. o. 1997 970. 4674. 0. 129. 1866. 92.27 0. 0. 1998 987. q752. 0. 49. 1817. aq.19 D. 0. 1999 10D~. 4835. o. 1. 1816. 80.9'1 0. 0. 2000 10ZO. 4913. o. 45. 1771. 73.65 D. 0. 2001 1oq5, 5032. 0. o. 1771. 69.53 0. 0. 2002 1070. 5152. 600. '15. 2326. 117.'17 600. 1855. 2D03 1093. 5266. o. 53. 2273. 107.87 0. 0. 2ooq 1118. 5386. o. 139. 2134. 90.84 0. 0. 2005 1143. 5505. o. 89. 2046. 78.95 0. o. 2006 1178. 5672. o. 188. 1858. 57.74 o. o. 2007 1211. 5833. o. o. 1858. 53.39 0. 0. .. ALL UNITS •• .•••••• NEH UNITS ONLY ••••••• . •.•••••••••••••••••.••• COST SUIU·fARY ••••.••.•••••••••••••••• YEAR PROD. COST FIXED 0 I. H FIXED CHARGES ANNUAL CUH. ANNUAL PRESENT NORTH cuu. PRES. HORTH ---------------------...... ___________ .., __________ ----------------------------- 1988 102. 1. 1'1. 117. 117. 99. 99. 1989 111. 1. 1'1. 126. 244. 103. 202. 1990 120. 1. 1'1. 136. 379. 107. 308. 1991 128. 1. 14. 1'14. 523. 109. 417. 1992 136. 1. 14. 152. 675. 112. 529. 1993 8. 24. 233. 265. 940. 188. 717. 199'1 11. 211. 233. 268. 1208. 184. 900. 1995 1'1. 24. 233. 271. 1479. 179. 1080. 1996 17. 24. 233. 27'1. 1753. 175. 1255. 1997 21. Zl.J. 233. 277. 2031. 171. 1'126. 1998 24. 24. 233. 280. 2311. 167. 159'1. 1999 27. 2'1. 233. 284. 2595. 164. 1757. 2000 31. 24. 233. 288. 2883. 160. 1918. 2001 36. 2'1. 233. 293. 3175. 158. 2075. 2002 0. 34. 325. 360. 3535. 187. 2262. 2D03 0. 34. 325. 360. 3895. 181. 2443. 2004 0. 34. 325. 360. 4254. 175. Z618. 2005 0. 34. 325. 360. 4614. 169. 2786. Z006 0. 34. 325. 360. 4973. 163. 2949. 2007 0. 34. 325. 360. 5333. 157. 3107. EXT. 2439. 5545. NOTES -ANtlUAL COSTS ARE IN IIILLIONS OF CURREtfT DOLLARS. -PRESENT NORTH COSTS ARE IN IIILLIOtlS OF DOLLARS DISCOUNTED TO THE BEGINNifiG OF 1983. TABLE 12.4-14 RAILBELT GENERATION EXPANSION PLANS SENSITIVITY ANALYSIS TO RAILBELT NO-GROWTH CASE 0% Load Growth per year Without Susitna Thermal Plants only 60 MW Bradley Lake 90 MW Bradley Lake>'< 135 MW Bradley Lake* MILLIONS OF 1983 DOLLARS PRESENT WORTH COST PRESENT \WRTH SAVINGS 3,194 2,966 2,990 3,010 228 204 184 * Includes Anchorage/Soldotna 230 KV Transmission Line ~--------TABLE 12.4-15 Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Total NEW GENERATION CAPACITY ADDED BASE CASE (THERMAL PLANTS ONLY) 0% LOAD GROWTH SENSITIVITY CASE* Combined Cycle Coal Gas Turbine 200 MW 200 MW 70 MW 11 Capacity tl Capacity 11 Capacity Units MW Units MW Units MW 1.0 200 1.0 200 2.0 140 1.0 200 2.0 400 1.0 200 2.0 140 *Assumed 0% load growth was used in combination with fuel prices from the Sherman Clark NSD Case • .____ ________ TABLE 12.4-16 Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Total NEW GENERATION CAPACITY ADDED 90 MW BRADLEY LAKE PROJECT 0% LOAD GROWTH SENSITIVITY CASE* Hydroelectric Combined Cycle Coal Gas Turbine 200 MW 200 MW 70 MW IF Capacity II Capacity II Capacity fj Capacity Units MW Units MW Units MW Units MW 1.0 90 1.0 200 2.0 140 1.0 70 1.0 200 1.0 90 1.0 200 1.0 200 3.0 210 *Assumed 0% load growth was used in combination with fuel prices from the Sherman Clark NSD Case • .____---------TABLE 12.4-17 Natural Gas Energy Fuel Cost Year GWH $106 1988 2,124 63 1989 2,124 64 1990 2,124 66 1991 2,124 68 1992 2,119 70 1993 2,119 72 1994 2,106 73 1995 2,097 74 1996 2,097 76 1997 2,584 87 1998 2,570 88 1999 2,570 91 2000 2,682 98 2001 2,682 100 2002 2,661 102 2003 2, 711 101 2004 2,714 105 2005 2,869 114 2006 1,687 72 2007 1,687 74 GENERATION BY FUEL CASE BASE CASE (NEW THERMAL PLANTS ONLY) 0% LOAD GROWTH SENSITIVITY CASE* Coal Oil H:t:droelectric* Energy Fuel Cost Energy Fuel Cost Energy Fuel Cost GWH $106 GWH $106 GWH $106 675 17 21 1 190 0 675 17 21 1 190 0 675 18 21 1 190 0 675 18 21 1 190 0 675 19 26 1 190 0 675 19 26 2 190 0 675 20 -39 2 190 0 675 20 47 3 190 0 675 20 46 3 190 0 219 7 16 1 190 0 219 7 28 2 190 0 219 7 28 2 190 0 89 3 42 3 190 0 89 3 42 3 190 0 89 3 57 4 190 0 89 3 16 1 190 0 89 3 0 0 190 0 89 3 0 0 42 0 1,265 35 0 0 42 0 1,265 3? 0 0 42 0 *Assumed 0) load growth was used in combination with fuel prices from the Sherman Clark NSD Case. **Gross generation. Total Rail belt Energy** Fuel Cost GwH $106 3,010 81 3,010 83 3, o;w 85 3,010 88 3' 0!1..0 90 3,010 92 3,0~0 95 3,010 97 3,099 100 3,008 94 3,006 97 3,0p6 100 3,0b3 103 3,003 106 2,997 109 3,0p7 106 2,9~3 108 3,000 117 2,994 107 2,994 110 L-..--------------~--------..l---TABLE 12.4-18 Natural Gas Energy Fuel Cost Year GWH $106 1988 1 '796 48 1989 1,796 49 1990 1,796 51 1991 1,796 52 1992 1,795 54 1993 1, 795 55 1994 1,792 56 1995 1,790 58 1996 1,790 59 1997 2,218 79 1998 2,246 71 1999 2,246 73 2000 2, 376 79 2001 2,376 82 2002 2,371 84 2003 2,357 86 2004 2,382 89 2005 2,528 100 2006 1, 343 57 2007 1,185 50 GENERATION BY FUEL CLASS 90 MW BRADLEY LAKE PROJECT 0% LOAD GROWTH SENSITIVITY CASE* Coal Oil H:t:droelectric** Energy Fuel Cost Energy Fuel Cost Energy Fuel Cost GWH $10 6 GWH $10 6 GWH $10 6 675 17 4 0 535 0 675 17 4 0 535 0 675 18 4 0 535 0 675 18 4 0 535 0 675 19 5 0 535 0 675 19 5 0 535 0 675 20 7 0 535 0 675 20 9 1 535 0 675 20 9 1 535 0 233 7 22 1 535 0 221 7 7 0 535 0 221 7 7 1 535 0 89 3 9 1 535 0 89 3 9 1 535 0 89 3 13 1 535 0 89 3 24 2 535 0 89 3 0 0 535 0 89 3 0 0 387 0 1,269 35 0 0 387 0 1,433 40 0 0 387 0 *Assumed O% load growth was used in combination with fuel prices from the Sherman Clark NSD Case. **90 MW Bradley Lake Project plus existing hydroelectric plants. ***Gross generation • Total Rail belt Energy***Fuel Cost GWH $106 3,010 65 3,010 67 3,010 69 3,010 71 3,010 72 3,010 75 3,010 77 3,010 78 3,010 80 3,010 87 3,010 78 3,010 81 3,009 83 3,009 85 3,008 87 3,P06 91 3,006 92 3,004 103 3,000 91 3,005 90 ....__ ____ __,_ _______ _..;;, ________ --+---TABLE 12.4-19 EXPANSION PLAN SUMMARY BASE CASE (THERMAL PLANTS) NO GROWTH CASE ELECTRIC POHER RESEARCII INSTITUTE BRAOLEY LAKE EGEAS REPORT VER 00 LEV 00 EXPAHSIOH PLAH SUID·IARY ******************************************************************************************************************* ... *** PLAH 1 PEAH EHERGY • • • • • • CAPACITY, HH •••••• , RESERVE •••••••••• HEH UltiTS •••••••••• YEAR LOAD, HH GHH INSTALLED RETIRED TOTAL PERCENT CAPACITY oHH CAPITAL COSTS,IIt -----------__ .. _____________ BEliCH 625. 3010. 1079. 72.59 1988 625. 3010. o. 6. 1079. 72.59 o. o. 1989 625. 3010. o. o. 1079. 72.59 o. 0. 1990 625. 3010. o. 1. 1078. 72.50 o. 0. 1991 625. 3010. o. 19. 1059. 69.52 o. 0. 1992 625. 3010. o. 31. 1028. 64.50 o. 0. 1993 625. 3010. o. 8. 1021. 63.30 o. 0. 1994 625. 3010. o. 28. 993. 58.82 o. o. 1995 625. 3010. o. 20. 973. 55.68 0. o. 1996 625. 3010. 0. 88. 885. •11.63 0. 0. 1997 625. 3010. 200. 129. 956. 52.93 200. 237. 1998 625. 3010. o. 49. 907. 45.17 0. 0. 1999 625. 3010. o. 1. 906. 45.02 o. 0. 2000 625. 3010. o. 45. 861. 37.81 o. o. 2001 625. 3010. o. o. 861. 37.81 o. o. 2002 625. 3010. o. 45. 816. 30.61 o. o. 200] 625. 3010. 200. 53. 963. 54.08 200. 237. 2004 625. 3010. o. 139. 824. 31.86 0. 0. 2005 625. 3010. 140. 89. 876. 40.10 140. 96. 2006 625. 3010. 200. 188. 888. 42.02 zoo. 526. 2007 625. 3010. o. o. 888. '12.02 o. o. • • All UltiTS •• ....... HEH UltiTS OHLY ....... .. ...................... COST Sl.tiHARY ........................ YEAR PROD. COST FIXED 0 & H FIXED CHARGES AKHI.IAL CUI1. AtHJAl PRESENT HORTH CUH. PRES. HORTH -------------------------------------------------------------------------- 1988 89. 0. 0. 89. 89. 75. 75. 1989 91. 0. 0. 91. 179. 74. 148. 1990 93. o. o. 93. 272. 73. 221. 1991 95. o. o. 95. 367. 72. 294. 1992 98. o. o. 98. 465. 72. 365. 1993 100. o. 0. 100. 565. 71. 436. 1994 103. o. o. 103. 668. 70. 506. 1995 105. o. o. 105. 773. 70. 576. 1996 108. o. o. 108, 880. 69. 645. 1997 101. 2. 13. 115. 995. 71. 716. 1998 103. 2. 13. 118. 1113. 70. 786. 1999 106. 2. 13. 121. 1234. 70. 856. 2000 110. 2. 13. 125. 1359. 69. 925. 2001 113. 2. 13. 128. 1486. 69. 994. 2002 116. 2. 13. 131. 1617. 68. 1062. 2003 111. 3. 26. 140. 1757. 70. 1132. 2004 11'1. 3. 26. 143. 1900. 69. 1202. 2005 124. 4. 32. 160. 2060. 75. 1271. 2006 113. 7. 61. 181. 2240. 82. 1359. 2007 115. 7. 61. 183. 2'12'1. eo. 1439. EXT. 1755. 3l9'L tlOTES -AHHUAL COSTS ARE IIi HILLIOHS OF CURREHT DOLLARS. -PRESEHT HORTH COSTS ARE IIi IIILLIOHS OF DOLLARS DISCOUttTED TO THE BEGIHHIHG OF 1983. TABLE 12.4-20 EXPANSION PLAN SUMMARY 90 MW BRADLEY LAKE PROJECT NO GROWTH CASE ELECTRIC POHER RESEARCH INSTITUTE BRADLEY LAI<E EGEAS REPORT VER 00 LEV 00 EXPAHSIDH PLAit SUitWIT PLAit PEAK EHER&Y •••••• CAPACITY, HH ••••••• RESERVE •••••••••• NEH '-'tiTS •••••••••• UAR LOAD, HH &HH INSTALLED RETIRED TOTAL PERCENT CAPACITYoHH CAPITAL COSTS,Ht ------------------------------------------- BENCH 625. 3010. 1079. 72.59 1988 625. 3010. 90. '· 1169. 86.99 90. 2811. 1989 625. 3010. o. o. 1169. 86.99 o. o. 1990 625. 3010. o. 1. 1168. 86.90 o. o. 1991 625. 3010. O; 19. 11'19. 8].92 0. o. 1992 625. 3010. 0 .• 31. 1118. 78.90 o. o. 1993 625. 3010. o. II. 1111. 77.70 o. o. 199'1 625. 3010. o. 28. 1083. 73.22 o. o. 1995 625. 3010. o. 20. 1063. 70.08 o. o. 1996 625. 3010. o. 88. 975. 56.03 o. o. 1997 625. 3010. o. 129. M6. 35.33 o. o. 1998 625. 3010. zoo. 49. 997. 59.57 200. Zl7. 1999 625. 3010. o. 1. 996. 59.42 o. o. 2000 625. 3010. o. 45. 951. 52.21 o. o. 2001 625. 3010. o. o. 951. 52.21 o. o. 2002 625. 3010. o. 45. 906. 45.01 0. o. 2003 625. 3010. o. Sl. 85l. 36.'18 o. o. 200'1 625. 3010. 1'10. 139. 85'1. 36.66 140. 96. 2005 625. 3010. 70. 89. 836. 33.70 70. 48. 2006 625. 3010. 200. 188. 8'18. 35.62 200. 526. 2007 625. 3010. o. o. 848. 35.62 o . o. .. ALL '-'tiTS •• .. • • ••• HEN '-'tiTS DilLY ....... .. ...................... COST SUitWIT ........................ YEAR PROD. COST fiXED 0 & H FIXED CHARGES AlftJAL Cl.ll. AlftJAL PRESENT HORTH Cl.ll. PRES. NORTH ------------------------------------------------------------------------- 1988 71. 1. 1'1. 87. 87. 73. 13. 1989 73. 1. 1'1. 89. 176. 72. 145. 1990 75. 1. 14. 90. 266. 71. 216. 1991 71. 1. 14. 92. 358. 70. 287. 1992 78. 1. 1'1. 9'1. 45l. 69. 356. 1993 80. 1. 1'1. 96. 549. 68. 42'1. 1994 82. 1. 1'1. 98. 6'17. 67. 491. 1995 8'1. 1. 1'1. 100. 747. "· 557. 1996 86. 1. 1'1. 102. M9. 65. 623. 1997 95. 1. 14. 111. 960. 68. 691. 1998 83. 3. 27. 113. 1013. 68. 759. 1999 85. 3. 27. 115. 1189, 67. 825. 2000 88. 3. 27. 118. 1307. "· 891. 2001 90. 3. 27. 120. 1lf27. 65. 956. 2002 92. 3. 27. 123. 15lf9. 6lf. 1019. 2003 96. 3. 27. 126. 1675. 63. 1083. 2004 98. 3. 34. 135. 1810. 65. 1148. 2005 109. 3. 37. 150. 1960. 70. 1218. 2006 96. 7. "· 169. 21Z9. 71. 1295. 2007 94. 7. "· 167. 2296. 73. 1368. EXT. 1516. 28811. NOTES -AtKIAL COSTS ARE IN HILLIDHS OF CURRENT DOLLARS. -PRESENT liORTH COSTS ARE IN NIUiotiS OF DOLLARS DISCDU'fTED TO THE BEGitiiiNG OF 1983. TABLE 12.4-21 Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Total NEW GENERATION CAPACITY ADDED BASE CASE (THERMAL PLANTS ONLY) DOR 50% CASE (JULY 1983) Combined Cycle Coal Gas Turbine 200 MW 200 MW 70 MW II Capacity fJ Capacity II Capacity Units MW Units MW Units MW 1.0 200 1.0 200 1.0 200 1.0 70 1.0 70 1.0 200 2.0 140 1.0 200 5.0 1,000 -0--0-4.0 280 ~-----------TABLE 12.4-22 Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Total NEW GENERATION CAPACITY ADDED 90 MW BRADLEY LAKE PROJECT DOR 50% CASE (JULY 1983) Hydroelectric Combined Cycle Coal 200 MW 200 MW II Capacity II Capacity II Capacity Gas Turbine 70 MW II Capacity Units MW Units MW Units MW Units MW 1.0 90 1.0 200 1.0 200 l.O 70 1.0 70 1.0 70 l.O 70 1.0 200 l.O 70 l.O 200 1.0 70 1.0 90 4.0 800 -0--0-6.0 420 '------------TABLE 12.4-23 Natural Gas Energy Fuel Cost Year GWH $106 1988 3,012 71 1989 3,099 75 1990 3,185 78 1991 3,177 77 1992 3,261 80 1993 3,235 78 1994 3,255 78 1995 3,308 78 1996 3, 701 81 1997 4,045 86 1998 4,102 87 1999 4,170 88 2000 4,256 89 2001 4' 347 91 2002 4,447 93 2003 4,534 96 2004 4,685 97 2005 4,924 102 2006 5,071 105 2007 5,197 198 * Gross generation. GENERATION BY FUEL CLASS BASE CASE (NEW THERMAL PLANTS ONLY) DOR 50% CASE (JULY 1983) Existing Coal Oil Hydroelectric Energy Fuel Cost Energy Fuel Cost Energy Fuel Cost GWH $106 GWH $106 GWH $106 492 12 26 1 190 0 507 12 34 2 190 0 518 12 43 2 190 0 523 12 98 4 190 0 528 12 62 3 190 0 532 12 131 6 190 0 535 13 161 7 190 0 534 13 161 7 190 0 329 8 43 2 190 0 77 2 19 1 190 0 80 2 26 1 190 0 81 2 25 1 190 0 51 1 34 1 190 0 54 1 36 1 190 0 55 1 30 1 190 0 56 1 31 1 190 0 32 1 0 0 190 0 38 1 0 0 42 0 19 1 0 0 42 0 21 1 0 0 42 0 Total Railbelt Energy* Fuel Cost GWH $10 6 3,719 84 3,830 88 3,936 93 3,989 94 4,041 95 4,089 96 4,141 97 4,193 98 4,263 91 4, 331 89 4, 398 90 4,~67 90 4,531 92 4,626 94 4,722 96 4 ,8ll 98 4,906 97 5,Q04 103 5,132 106 5,261 108 L....---------------..,;..-_----------TABLE 12.4-24 GENERATION BY FUEL CLASS 90 MW BRADLEY LAKE PROJECT DOR 50% CASE (JULY 1983) Natural Gas Coal Oil H~droelectric* Energy Fuel Cost Energy Fuel Cost Energy Fuel Cost Year GWH $106 GWH $106 GWH 1988 2,498 64 645 15 40 1989 2,592 68 648 15 54 1990 2,862 66 526 12 12 1991 2,889 66 531 12 34 1992 2,952 67 536 13 19 1993 2,~65 67 540 13 50 1994 3,004 67 539 13 64 1995 3,044 68 544 13 12 1996 3,097 69 549 13 79 1997 3,634 76 131 3 30 1998 3,670 76 150 3 41 1999 3, 747 78 161 4 25 2000 3,911 81 76 2 15 2001 4,002 84 76 2 18 2002 4,100 86 77 2 15 2003 4,188 89 78 2 16 2004 4, 317 88 60 1 0 2005 4,556 94 61 1 0 2006 4 '723 97 28 1 0 2007 4,850 100 32 1 0 *90 MW Bradley Lake Project plus existing hydroelectric plants. **Gross generation • $106 2 2 1 2 1 2 3 3 3 1 2 1 1 1 1 1 0 0 0 0 Energy Fuel Cost GWH $106 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 535 0 387 0 387 0 387 0 Total Rail belt Energy** Fuel Cost GWH $106 3,7;l9 81 3,830 86 3,936 78 3,989 80 4,042 81 4,090 82 4' 143 83 4,195 84 4,252 85 4' 331 80 4, 396 82 4 '4.68 82 4,5137 84 4 ,6r32 86 4,7~8 88 4,817 92 4,912 89 5,005 95 5,139 97 5,2M 101 .____~ ____________ ..;.._ _______ __.__ __ TABLE 12.4-25 EXPANSION PLAN SUMMARY BASE CASE (THERMAL PLANTS) DOR 50% CASE ELECTRIC PotiER RESEARCH INSTITUTE BRADLEY LAHE EGEAS REPORT VER 00 LEV 00 EXPANSION PLAN SUIIIARY ***********************•************************************************************************•*********************' PLAN PEAK EtiERGY •••••• CAPACITY, HH ••••••• RESERVE •••••••••. NEH UNITS .......... YEAR LOAD, 1-!H GliH INSTALLED RETIRED TOTAL PERCENT CAPACITY ,.IH CAPITAL COSTS ,.1$ ------------------------------------ BEliCH 772. 3718. 1079. 39.73 1968 772. 3719. 200. 6. 1279. 65.60 200. 237. 1969 795. 3830. 0. o. 1279. 60.79 o. o. 1990 817. 3936. o. 1. 1278. 56.38 o. 0. 1991 828. 3989. o. 19. 1259. 52.06 0. o. 1992 e39. ~0'12. o. 31. 12~8. '16.32 o. o. 1993 e'l9. '1090. o. 8. 1221. '13. 73 o. 0. 19911 860. '11~3. o. 28. 1193. 38.63 0. o. 1995 e71. 4196. o. 20. 1173. 311.63 0. 0. 1996 866. 4265. 200. ea. 1285. 45.13 200. 237. 1997 900. 433'1. zoo. 129. 1356. 50.67 200. Z37. 1998 914. ~'103. o. ~9. 1307. ~3.01 o. o. 1999 928. '1'171. o. 1. 1306. '10. 72 0. 0. 2000 9~3. '15'10. 0. 'IS. 1261. 33.80 0. 0. 2001 962. '1636. o. 0. 1261. 31.05 0. 0. 2002 9e2. '1731. 70. 'IS. 1286. 30.95 70. ~e. 2003 1001. '1821. 70. 53. 1303. 30.17 70. 'le. ZOO 'I 1021. ~916. 200. 139. 13611. 33.63 zoo. 237. zoos 10'11. 5012. 1'10. 89. 1'116. 36.0'1 1'10. 96. Z006 1068. 514'1. ~00. 188. 1'128. 33.66 200. 237. Z007 1096. 5276. o. 0. 1428. 30.31 0. o . .. ALL utiiTS .. .. .. .. • NEH UHITS OILY ....... • , ...................... COST SUHUARY •••• , ................... YEAR PROD. COST FIXED 0 & H FIXED CHARGES ANNUAL CUH. ANNUAL PRESENT HORTH CUU. PRES. HORTH -------------------------------------------------------------------------- 196B 92. 2. 13. 106. 106. 90. 90. 19e9 97. 2. 13. 111. 21e. 91. teo. 1990 102. 2. 13. 116. 33'1. 91. 271. 1991 103. 2. 13. 117. ~51. e9. 360. 1992 10'1. 2. 13. 119. 570. e7. qqe. 1993 106. 2. 13. 120. 690. es. 533. 1994 107. 2. 13. 1~2. e11. e3. 616. 1995 10e. 2. 13. 122. 934. el. 697. 1996 '99. 3. 26. 128. 1062. e2. 779. 1997 97. 5. 39. 1'10. 1202. e7. 865. 199e 9e. 5. 39. 142. 13'1'1. 85. 950. 1999 99. 5. 39. 1'12. 1~86. e2. 1032. 2000 101. 5. 39. 14'1. 1630. eo. 1112. 2001 103. 5. 39. H6. 1776. 79. 1191. 2002 lOS. 5. '12. 152. 1929. 79. 1270. 2003 10e. 5. '15. 159. 2De7. 80. 1350. 200'1 107. 7. 58. 172. 2259. 83. 1'133. 2005 113. 7. 65. 185. 2~'1<1. 87. 1520. 2006 116. 9. 78. 203. 26'17. 92. 1612. 2007 119. 9. 7e. 206. Z853. 90. 1702. EXT. 1658. 3361. NOTES -ANIIUAL COSTS ARE IN IIILLIONS OF CURRENT DOLLARS. -PRESENT HORTH COSTS ARE IN tiiLLIOtiS OF DOLLARS DISCOUHTED TO THE BEGIHNIIIG OF 1983. TABLE 12.4-26 EXPANSION PLAN SUMMARY 90 MW BRADLEY LAKE PROJECT DOR 50% CASE ELECTRIC POWER RESEARCH IHSTITUTE BRAOLEY LAHE EGEAS REPORT VER 00 LEV 00 EXPANSIOH PLAN SUIRIARY *******************************************•****************************************••························•******** PLAN PEAK ENERGY • • • • •• CAPACITY, IIH ••••••• RESERVE •••••••••• tiEl~ UNITS •••••••••• YEAR LOAD, lllf GI~H INSTALLED RETIRED TOTAL PERCENT CAPACITY ,IIH CAPITAL COSTS,IIS --------------------------- BEliCH 772. 3718. 1079. 39.73 1986 772. 3719. 90. 6. 1169. 51.35 90. 268. 1989 795. 3630. 0. 0. 1169. 46.96 0. 0. 1990 817. 3936. 200. l. 1368. 67.40 200. 237. 1991 828. 3969. 0. 19. 1H9. 62.92 0. o. 1992 839. 4042. 0. 31. 1316. 57.04 0. 0. 1993 849. 4090. 0. e. 1311. 54.33 0. 0. 1994 860. 41<U. 0. 28. 1283. 49.09 0. 0. 1995 871. 4196. 0. 20. 1263. 44.96 o. 0. 1996 886. 4265. o. 86. 1175. 32.71 0. 0. 1S97 900. 4334. 200. 129. 1246. 36.45 200. 237. 1996 914. 4403. o. 49. 1197. 30.98 0. o. 1999 9Z8. 4471. 70. 1. 1266. 36.41 70. 48. 2000 943. 4540. 70. 45. 1~91. 36.98 70. 48. 2001 962. 4636. 0. o. 1291. 34.16 0. o. 2002 962. 4731. 70. 45. 1316. 34.00 70. 46. ~003 1001. 4821. 70. 53. 1333. 33.17 70. 46. ~004 1021. 4916. 200. 139. 1394. 36.57 200. 237. 2005 1041. 5012. 70. 89. 1376. 32.19 70. 46. 2006 1068. 5144. 270. 188. 1458. 36.47 270. 285. 2007 1096. 5276. o. 0. 1458. 33.05 0. 0. • • ALL UHITS •• ....... NEH UHITS Otll Y ....... • ....................... COST SUIIIlARY ........................ YEAR PROD. COST FIXED 0 & II FIXED CHARGES ANNUAL CUll. ANNUAL PRESEIIT HORTH CUll. PRES. HORTH -------------------------------------------------------------------------- 1988 90. l. 14. 106. 106. 89. 89. 1969 96. 1. 14. 111. 217. 91. 160. 1990 86. 3. 27. 116. 333. 91. 271. 1991 87. 3. 27. 117. 450. 89. 360. 1992 88. 3. 27. 118. 569. 87. 447. 1993 90. 3. 27. 120. 668. 65. 531. 1994 91. 3. 27. 121. 809. 63. 614. 1995 92. 3. 27. 122. 932. 81. 695. 1996 94. 3. 27. 124. 1056. 79. 775. 1997 68. 4. 40. 132. 1188. 62. 856. 1996 90. 4. 40. 134. 1322. 80. 937. 1999 91. 5. 44. 139. 1461. eo. 1017. 2000 92. 5. 47. 144. 1605. 80. 1097. 2001 95. s. 47. 147. 1752. 79. 1176. 2002 98. 5. so. 153. 1906. eo. 1256. 2003 102. s. 54. 160. 2066. 81. 1336. 2004 98. 7. 67. 171. 2237. 63. 1419. 20QS 105. 7. 70. 182. 2419. 65. 1505. 2006 107. 9. 86. 202. 2621. 92. 1596. 2007 111. 9. 86. 206. 2827. 90. 1666. EXT. 1614. 3301. IIOTES • AIIIIUAL COSTS ARE IN IULLIOIIS OF CURRENT DOLLARS. -PRESENT HORTH COSTS ARE Ill llllliOIIS Of DOLLARS DISCOUNTED TO THE BcGitlNING OF 1981. TABLE 12.4-27 CAPITAL COSTS AND AVERAGE ANNUAL ENERGY 90 MW BRADLEY LAKE PROJECT FEASIBILITY STAGE AND SELECTED VALUES Feasibility Stage Values Values for Selected Plant * Includes IDC Capital Cost* Average Annual Energy, Millions 1983 $ GWH 287.95 300.00 345.4 369.2 NOTE: For description of Capital Costs and Annual Fixed O&M Costs, see Section 11 of this Report. L------------TABLE 12.4-28 SELECTED 90 MW BRADLEY LAKE PROJECT WITHOUT SUSITNA PRESENT WORTH COSTS AND SAVINGS Base Case 90 MW Bradley Lake Project Present Worth, Millions 1983 $ Total Cost Savings Due to Bradley Lake 5,832 5,455 377 ..______ ________ TABLE 12.4-29 EXPANSION PLAN SUMMARY SELECTED 90 MW BRADLEY LAKE PROJECT REFERENCE CASE LOAD ELECTRIC POHER RESEARCH ItiSTITUTE BRADLEY LAI<E EGEAS REPORT VER 00 LEV 00 EXPAHSIOH PLAH S~IHARY ***************************************************•***********•**************••••••••********************************* PLAH PEAl< EHERGY •••••• CAPACITY, IIH, •••••• RESERVE • ......... HEH UHITS .......... YEAR LOAD, HH GHH IHSTALLED RETIRED TOTAL PERCEHT CAPACITY oi-IH CAPITAL CDSTS,H$ --------------------------- BEliCH 780. 3757. 1079. 38.Z9 1988 179. 315'1. 90. 6. 1169. '19.96 90. 300. 1989 810. 3899. zoo. o. 1369. 69.06 zoo. Z31. 1990 639. '10'10. o. 1. 1368. 63.12 o. o. 1991 859. '1139. o. 19. 13'19. 57.05 o. o. 1992 879. '1232. o. 31. 1318. 50.01 o. o. 1993 898. '1326. 0. 8. 1311. '15.93 o. 0. 199'1 918. '1'119. o. Z8. 1Z8l. 39.79 o. 0. 1995 937. '1513. o. zo. 1Z63. 3'1.80 0. 0. 1996 9511. '1596. zoo. 88. 1375. '1'1.1Z zoo. 237. 1997 970. 467'1. zoo. 1Z9. 1446. '18.99 zoo. Zl7. 1998 987. 4752. o. '19. 1197. '11.62 o. o. 1999 1004. '1815. 0. 1. 1196. 39.10 o. o. 2000 1020. '1913. 0. '15. 1151. 32.'17 o. 0. Z001 10'15. 5012. 70. o. 1'121. 36.03 70. '18. Z002 1070. 515Z. 70. 45. 1'1'16. 35.21 70. '18. 2003 1093. 5266. zoo. 51. 1591. '15.69 200. 526. 200'1 1118. 5386. o. 139. 1454. 30.03 o. 0. 2005 11113. 5505. 200. 89. 1566. 36.96 zoo. 526. 2006 1178. 567Z. zoo. 188. 1578. 33.97 zoo. 526. 2007 1211. 5831. o. o. 1578. 30.27 o. o. • • ALL UHITS •• • ...... HEH UHITS ONI. Y ••••••• .. ...................... COST SUilllARY ........................ YEAR PROD. COST FIXED 0 l H FIXED CHARGES ANNUAL CIJ1. AHHUAL PRESEHT HORTH CUI1. PRES. HORTH -------------------------------------------------------------------------- 1988 101. 1. 15. 117. 117. 99. 99. 1989 93. 3. Z8. 1Z'I. Z'l1. 101. 199. 1990 101. 3. 28. 132. 313. 103. 303. 1991 108. 3. 28. 138. 511. 105. '108. 1992 114. 3. 28. 1'15. 655. 106. 51'1. 1993 121. 3. 28. 152. 807. 107. 621. 199'1 1Z8. 3. Z8. 159. 966. 109. 730. 1995 135. 3. 28. 166. 1132. 110. 8'10. 1996 1Z9. II. 41. 17'1. 1306. 111. 951. 1997 132. 6. 5'1. 191. 1497. 118. 1069. 1998 138. 6. 5'1. 198. 1695. 118. 1187. 1999 1'15. 6. 5'1. ZO'I. 1899. 118. 1305. 2000 152. 6. 5'1. 211. 2110. 118. 1'123. 2001 160. 6. 57. Z2'1. 233'1. 1ZO. 1543. 2002 169. 6. 60. 236. 2570. 123. 1666. 2003 162. 10. 89. 261. Z83l. 131. 1797. 200'1 171. 10. 89. Z70. 3101. 131. 1928. 2005 171. 1'1. 118. 302. 3'103. 1'12. 2070. 2006 166. 17. 1'16. 330. 3733. 149. 2219. 2007 117. 17. 1'16. 3'10. 4072. 149. 2368. EXT. 3082. 5451. NOTES -ANNUAL COSTS ARE IH HILLIOHS Of CURREHT DOLLARS. -PRESENT NORTH COSTS ARE IH IIILLIONS Of DOLLARS DISCOUtiTED TO THE BEGIHHIHG Of 1983. TABLE 12.4-30 PEAKING INTERMEDIATE BASE 0 0.2 0.4 0.6 0.8 1.0 CAPACITY FACTOR TYPICAL BUS-BAR COSTS ""'----------FIGURE 12.2-1 RAILBELT STAGE 1 KENAI PENINSULA N l---1 UNLIMITED TIEFLOW4 RA_ILBELT W/0 KENAI N)---1 STAGE 2 KENAI PENINSULA RAILBELT W/0 KENAI ---/ ....... / ' ' N,__-1 LIMITED TIE FLOW STAGE 3 LEGEND @ NEW CAPACITY ® EXISTING CAPACITY ~ LOAD STAGES IN EGEAS GENERATION EXPANSION ANALYSIS ..____ ______________ FIGURE 12.2-2 100 60 MW PLANT HOURS 8760 100 c <( 0 ...J 90 MW PLANT HOURS 8760 100 ~ c <( 0 ...J BRADLEY LAKE DISPATCH BY EGEAS 135 MW PLANT 8760 HOURS ..___ ______________ FIGURE 12.2-3 120 110 100 J: 3: ~ 90 --en ..J ..J :E 80 ..,., en 70 0 0 a: <( 60 co ch ::;) 50 co 0 w N 40 ..J w > 30 w ..J 20 10 0 0 0.1 0 135MW +230 kV LINE 0 = BRADLEY LAKE 0.2 0.3 0 90MW GAS TURBINE 0 60MW 0.4 0.5 0.6 0.7 CAPACITY FACTOR SHERMAN CLARK NSD CASE 0.8 0.9 1.0 ..___ ______________ FIGURE 12.4-1 120 110 100 :I: 3: 90 ~ Cl) ..J ..J 80 ::!: ..... 70 Cl) 0 0 a: 60 <( m ch 50 ::> m c 40 w N ..J w 30 > 135MW +230 kV LINE ~------~6=0~M:W~0~·~--~~~~~~~======:1 90 MW COMBINED CYCLE w ..J 20 0 = BRADLEY LAKE 10 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 CAPACITY FACTOR DOR 50% CASE (JULY 1983) ....___ ______________ FIGURE 12.4-2 110 100 :I: ~ 90 ......... Cl) ...J ...J 80 :2: ~--· Cl) 70 0 0 a: 60 <( a'.l ch ::> a'.l fa 40 N ...J w 30 > w ...J 20 10 0= BRADLEY LAKE 0 90MW CAPACITY FACTOR SHERMAN CLARK NSD CASE SELECTED 90 MW PLANT GAS TURBINE L-----------------FIGURE 12.4-3 13 FINDINGS AND RECOMMENDATIONS 13. FINDINGS AND RECOMMENDATIONS 13. 1 FINDINGS 13.1.1 Introduction The findings address major portions of the study efforts and the overall objective of the study for selecting a technically, economically preferred plan for development of Hydroelectric Power Project. environmentally, and the Bradley Lake These findings are based on available data and information gathered during the study, on preliminary engineering and technical investigations, and on environmental and economic evaluations. 13.1.2 Technical Findings Foundation conditions in the area of the main dam, powerhouse, access roads, and barge channel are considered satisfactory for the development of these structures. Further, it was determined that the use of a tunnel boring machine for excavating the main portion of the power tunnel is feasible on the basis of the available data and represents the least cost alternative. Conventional drill and blast, as well as raised boring techniques can be applied to other appropriate sections of the power conduit such as the portals, the inclined shaft and short tunnel lengths. Exploratory work and available data also indicate that the power tunnel can be excavated through the Bradley River and Bull Moose fault zones using these methods. Further, combined use of these techniques will result in a lower total project cost without extending the construction schedule developed in previous studies. The findings show that Pelton units, rather than Francis units, are preferred for the Bradley Lake Project. The Pelton units offer lower total project costs, better response to peak load following operations, less complicated control equipment, easier maintenance, and avoidance of immersion of the turbine equipment and penstock in tidewater. 13-1 With respect to the main dam, the findings show that a concrete faced rockfill dam ·is preferred because of lower cost, greater use of natural material, and ease of construction. A dam built to accommodate a maximum operating pool for generation of elevation 1180 was selected for the preferred plan. This pool level provides essentially optimum storage for generation, avoids suspect areas of possible reservoir rim leakage near the Battle Creek headwaters, and allows maximum effective use of available riverbed area and channel topography for the development of the dam. Inclusion of the Middle Fork Diversion concept to seasonally divert water to Bradley Lake was found technically and economically feasible. The estimated additional energy generated by use of Middle Fork flows is 16 GWH per year. Including these seasonal divers ion flows, the 90 MW preferred plant could provide about 378 GWH of average annual energy if water is not released for maintaining aquatic habitat and about 369 GWH when some of the storage is used habitat. Average month historical to supplement annual firm period was natural flows, energy generation computed to be respectively. These energy values represent available at the generator leads. as needed for aquatic during the critical 44 348 GWH and 334 GWH, the total plant output Two 115 kV parallel transmission lines, each capable of handling the full plant output, are provided for greater reliability when transmitting power to the Kenai Peninsula transmission line grid. Study findings also show that the selected 90 MW plant will not require another transmission line between Soldotna and Anchorage as the existing 115 kV line is capable of providing reserve sharing and economy interchange between Anchorage and the Kenai Peninsula. Two separate camps will better support the construction activities of the project. A lower camp near tidewater will serve the powerhouse, main tunnel, and transmission line construction; and an upper camp will support construction of the main dam, diversion tunnel, Middle Fork and other structures such as the intake channel, upper tunnel and gate shaft. Development of the proposed upper camp will require additional baseline 13-2 data to further assess its technical feasibility as well as its impact to the local environment. Development of an access channel and barge basin at Sheep Point is technically feasible and cost effective with less environmental impacts than other alternatives considered. Similarly, access road routes identified during the study are the best alignments possible for development, both from a technical and construction scheduling standpoint. 13. 1. 3 Costs and Economics For all plant capacities evaluated, developments with Pelton type turbines result in the lowest estimated capital cost. Although the Pelton turbine and generator equipment costs more than the related Francis equipment, powerhouse civil costs are less. In addition, surge facilities are not required for the Pelton turbine installations. Similarly, cost comparisons for the different dam types favored the recommended concrete faced rockfill dam over a concrete gravity dam. The utilization of a tunnel boring machine for the excavation of the major portion of the main power tunnel results in substantial savings over convential methods. The Overnight Cost Estimate for the preferred 90 MW plant is $283,019,000. This cost includes direct material, labor, engineering and design cost; cost for the owner's cost including previous expenditures and construction equipment; management of construction; realized for project studies and development; land rights cost; all risk insurance; and a contingency of 25 percent. The Overnight Cost Estimate reflects cost as of July 1983. Economic evaluations show that the 60, 90 and 135 MW installations studied for the Bradley Lake Project are economically beneficial for the Railbelt, both with and without the Susitna Hydroelectric Development. life-cycle savings result by using Bradley Lake in place generation alternatives. The optimum Bradley Lake project 13-3 Significant of thermal capacity is dependent on and sensitive to the projected load growth rate for the Railbelt area and the Kenai Peninsula. The economic evaluation studies showed that the 90 MW selected plan is the prefered choice at the reference load growth rate of an average 2. 8 percent per year as adopted in this study. Also, the findings show that this selected installation is less sensitive to load growth variations. The study findings show that the Bradley Lake options are very close in terms of annual energy developed from the project, with only 3 to 5 percent differences between the three capacities evaluated. The findings also show that the 90 MW installation would better respond to the load growth demands for capacity and energy for the Kenai Peninsula area and would result in greater relative cost savings (due to less transmission costs) when serving this area rather than the entire Railbelt region. In conclusion, the feasibility study findings indicate that the Bradley Lake Hydroelectric Power project is a technically feasible development, economically attractive and can be adopted to its environmental setting. 13.2 RECOMMENDATIONS Based on the above outlined findings and conclusions, it is recommended that the energy potential of Bradley Lake be developed utilizing a 90 MW, two unit Pelton turbine powerhouse, a concrete faced rockfill dam, a machined bored concrete lined power tunnel, the Middle Fork diversion, and two 115 kV parallel transmission lines. Efforts should now proceed with the preparation of a Federal Energy Regulatory Commission (FERC) License Application and continue with the definitive engineering-design phase of the work. In conjunction with the License Application it is recommended that unresolved environmental concerns and issues be addressed, and mitigation and enhancement plans be conceptually developed in the following areas: o Bradley River fishery habitat o Rehabilitation of the Martin River borrow areas 13-4 o Waterfowl nesting in select spoil areas o Moose dispersion and migration corridors o Environmental impacts along the preferred transmission line corridor and upper camp area To support the engineering-design phase of the work, it is recommended that field investigative programs be identified at an early stage to develop additional geologic, survey, and other engineering data. 13-5 14 BIBLIOGRAPHY 14. BIBLIOGRAPHY 1. Reanalysis of the Bradley Lake Hydroelectric Project, Main Report and Appendix 1A -U.S. Army Corps of Engineers, Alaska District, March 1978. 2. Reanalysis of the Bradley Lake Hydroelectric Project, Appendix 3 Economic and Environmental References, Alaska District Army Corps of Engineers -March 1978. 3. Bradley Lake Photo Control, COE August-Sept. calculation sheets plus 2 Rite Rain Field Books. 1979. Data and 4. Survey Bradley Lake Field Survey Information, Corps of Engineers 5. data with USGS maps and tidal bench marks. 1979 Survey Bradley calculations and February 1980. Lake Hydrographic Survey Outlet, 3 Rite Rain survey log books. COE with maps, December 1979 6. Survey Books (4)-Bradley Lake -Lake Stream Outlet, control levels, River topo, Lake cross sections. COE June 1980. See also Document #16. 7. Survey -Bradley Lake Hydrographic Outlet Topo, includes copies of 4 booklets and 2 depth sounding graphs. June 1980. 8. Design Memorandum No. 2, original & copy of an unnumbered plate drawn June 1980. Corps of Engineers. 9. Bradley Lake Drill Hole Locations -Preliminary Alignment, Corps of Engineers. June 1980. Reference field books in Document #11. 10. Bradley Lake Drill Hole Locations, with maps, computer printouts and calculations. No date. 11. Survey Books (7)-Bradley Lake Dam Alignment, Drill Holes & Powerhouse Tunnel, COE June-July 1980. See also Document #9. 12. Bradley Lake Dam Area Drill Hole Locations and Horizontal Control, with maps, computer printouts and survey data. COE. June-August 1980. 13. Bradley Lake Power Tunnel Alignment Drill Hole Locations, with maps and computer printouts. Power tunnel horizontal and vertical control calculations, transponder locations, final adjusted coordinates on upper and lower powerhouse, dam area vertical control, coordinates for boat basin and airstrip camp area and daily log of field surveys. June-September 1980. 14. Bradley Lake Project -Hewlett/Packard Notes, COE June-August 1980. Small ring-bound booklet. 15. Bradley Lake Depth Soundings, COE July 1980. Reference 2 BRA 92-06-06. 16. Bradley Lake -Lake Stream Outlet, COE July 1980. Reference 2 BRA 92-06-03. Also see Document #6 for 4 Field Books. 17. Surv~y -Staging Area, referencing Topo Map 2 BRA 92-06-05, computer printout, Corps of Engineers. July 1980 18. Survey -Bradley Lake Tidal Datums, USC & GS NOAA, ITech Levels, Horiz Control Data (General) Corps of Engineers, July-August 1980 19. Bradley Lake -Middle Fork Diversion Horizontal & Vertical Control, COE August 1980. Reference 2 BRA 92-06-07. See also Document #22-6 Rite Rain Field Books. 20. Survey -Bradley Lake Tailrace, referencing Topo Map 2 BRA 92-06-04 J-97, computer printout, Corps of Engineers, August 1980. 21. Survey -Access Road, referencing Topo Map 2 BRA 92-06-08, Corps of Engineers August through October 1980. 22. Survey Books (6)-Bradley Lake Project Middle Fork Diversion Alignment & Topo, COE Sept-Oct 1980. See also Document #19. 23. Survey Books (11)-Bradley Lake Access Road, COE fall 1980. 24. Survey -Bradley Lake Transmission Line Control, utilizing Topo Map 2 BRA 92-06-11, also includes copy of Inertial Survey Report for Gravulate Transmission Line and North Fork Diversion in Homer, Alaska Area by International Technology Limited Oct. 1980, Corps of Engineers. October 1980 25. Survey -Bradley Lake Barge Basin Staging Area, mise. data on Boat Basin Area & power tunnel drill holes. 1980-1981 Corps of Engineers. 26. Survey -Bradley Lake New Alignment Camps only -Upside down Design, with maps and computer data. May 26, 1981. 27. Design Memorandum No. 1, June 1981 Hydrology Bradley Lake Hydroelectric Project -U.S. Corps of Engineers, Alaska District. 28. Design Memorandum No. 1, Hydrology, Bradley Lake Project (DRAFT), U.S. Army Corps of Engineers -Alaska District. 29. Survey -Main, Airport & Portal Roads Design Version #1, utilizing Topo Map 2 BRA 92-06-01, Corps of Engineers July -August 1981. 30. Survey -Bradley Lake Airport Road Traverse Adjustment, Corps of Engineers November 1981. 31. Survey Bradley Lake Revised Calculations for Creek & Tunnel Alignment, Topo Map 2 BRA 92-06 12/10/81, Corps of Engineers. November 1981 32. Survey Bradley Lake Dam to River Crossing, Computer printout of curve data. Corps of Engineers 1981. 33. Survey-Main Access Road, Corps of Engineers 1981. 34. Survey Bradley Lake Mise. Information, includes Topo Maps 2 BRA 92-06-01 J97 & H100, 2 BRA 92-06-12 Sheet 8 of 8, and an unnumbered plate of Design Memorandum #2; and a Tide Schedule for Seldovia, Alaska. Corps of Engineers. 1981 35. Survey -Bradley Lake Supplement to 1981 Survey, Corps of Engineers. 1981 36. Survey -Bradley Lake Portal Road, Corps of Engineers 1981 & 1982. 37. Survey-Bradley Lake Intake Portals, Corps of Engineers misc. data. 38. Bradley Lake Hydroelectric Project Design Memorandum No. 2, February 1982, General Deslgn Memorandum -Volume 1 of 2, Main Report, U.S. Army Corps of Engineers, Alaska District. (2 copies) 39. Bradley Lake Hydroelectric Project Design Memorandum No. 2, February 1982, General Design Memorandum -Volume 2 of 2, Appendices, U.S. Army Corps of Engineers, Alaska District. (2 copies) 40. Environmental Impact Statement Engineers. March 1982. Appendices, U.S. Army Corps of 41. Bradley Lake Project Calculation Notebook for Barge Basin, Wind Speed and Wave Height, Seattle District, Army Corps of Engineers -May 1982. 42. Survey -Bradley Lake Design Comps for Structures/Tunnel Alignment, includes Topo Map J97 C-1, Corps of Engineers. October 6, 1982 43. Design Memorandum No. 3, Access & Construction Facilities Bradley Lake Project, Alaska-Department of the Army, Alaska District, Corps of Engineers (3 copies). 44. Final Environmental Impact Statement, August 1982, Bradley Lake Hydroelectric. Project, Alaska, U.S. Army Corps of Engineers, Alaska District. (2 copies) 45. "Economic Evaluation Procedure"-Federal Register (Vol. 44, No. 242), FERC/Corps of Engineers. 46. Survey -Bradley Lake Field Book Index, 51 booklets as indexed by the Corps of Engineers. Access Road (1-25), Access Road Camp Area, Airport Road, Tidal Observations, Battle Crk. X-Sections & Powerhouse, Drill hole ties, Main Access Road and Portal Road. 47. Bradley Lake Hydroelectric Project Plan of Finance, prepared by the Alaska Power Authority, April 1982. 48. State of Alaska Memorandum Bradley Lake Hydroelectric Project November 24, 1982 -written to Dr. Ronald D. Lehr, Director, from Eric P. Yould, Executive Director. 49. Fox River Flats Critical Habitat Area, Range 9 & 10 West, Map, Alaska Power Authority. 50. Marine Geophysical Survey -Western Bradley Lake, Alaska, Woodward- Clyde Consultants, November 1980 (2 copies). 51. Marine Geophysical Survey Western Bradley Lake, Alaska, submitted to COE by Woodward Clyde. Includes 3 maps showing Isopach Lake Sediments, lake bottom and elevation base of lake sediment. November 1980. 52. Forecasting Peak Elec.trical Demands for Alaska's Railbelt, Final Report issued by Woodward-Clyde Consultants for Acres American to Alaska Power Authority. December 1980. 53. Circulation and Dispersion of Bradley Lake River Water in Opper Kachemak Bay, prepared for Department of the Army, Alaska District, Corps of Engineers-December 31, 1980, Woodward-Clyde Consultants. 54. Design Earthquake Study -Report on the Bradley Lake Hydroelectric Project, prepared for Department of the Army, Alaska District, Corps of Engineers, Woodward-Clyde Consultants. 55. Geologic Reconnaissance Bradley Lake Access Road, Submitted to Department of the Army, Alaska District, Corps of Engineers, by Woodward-Clyde Consultants (2 copies). 56. Reconnaissance Geology, Bradley Lake Hydroelectric Project, Woodward-Clyde Consultants. (2 copies) 57. Bradley Lake Phase I Feasibility Study on Instream Flow Studies, final report submitted to Stone & Webster Engineering Corp. by Woodward-Clyde Consultants. October 1983. 58. Bradley Lake Phase I Feasibility Study on Construction Facilities, final report submitted to Stone & Webster Engineering Corp. by R&M Consultants. September 1983. 59. Bradley Lake Phase I Feasibility Study of Transmission Line System, final report submitted to Stone & Webster Engineering Corp. by Dryden & LaRue Consulting Engineers. September 1983. 60. Bradley Lake Phase I Feasibility Geotechnical Studies, final report submitted to Stone & Webster Engineering Corp. by Shannon & Wilson, Inc. September 1983. 61. Geologic Mapping Program, Bradley Lake Project, Dowl Engineers, January 1983. 62. Summary Report on Analysis of Construction Procedures and Schedules Bradley Lake Hydroelectric Project, R. W. Beck and Associates, Inc. , September 1982 (preliminary draft). (3 copies) 63. Kenai Peninsula Power Supply and Transmission Study, R. W. Beck and Associates, Inc. -December 1982. 64. Supplement, Kenai Peninsula Power Supply and Transmission Study, R.W. Beck and Associates, Inc. -December 1982. 65. Preliminary Results of the Railbelt Economic Analysis -letter from R.W. Beck and Associates dated February 21, 1983, written to Mr. Eric Marchegiani, P.E., Project Manager Alaska Power Authority. 66. Bradley Lake Project -Water Quality Report, prepared by Ott Water Engineers, Inc. 67. Generation Planning Studies, Susitna Hydroelectric Project. Close-out report, April 1982 by Acres American. 68. Feasibility Study of the Soldotna-Fritz Creek Energy Report R-2518, Homer Electric Assn, Commonwealth. June 1983 Transmission Line, Inc., by Gilbert/ 69. Power Requirements Study for Homer Electric Assn. , Inc. , by Burns & McDonnell. 1983 70. Power Requirements Study for Chugach Electric Association, Inc., Burns & McDonnell. 1983. 71. City of Fairbanks Municipal Utilities System Financial Statements, from Harza-Ebasco. 1979, 1980 & 1981. Also an hourly generation log for one week in each month of 1982. 72. Susitna FERC Application, Appendices Band D, Harza-Ebasco Report. July 1983. 73. Bradley Lake Hydroelectric Project, Homer, Alaska Findings and Recommendations, April 28, 1982 -Alaska State Legislature. 74. State of Alaska -Office of the Governor (letter), October 22, 1982 Bradley Lake Renewable Energy Hydroelectric Project Fe as, State I. D. No. AK820831-09, written to U.S. Department of the Army, Alaska District, Corps of Engineers from Bill Lucia, Deputy Director. 7 5. Bradley Lake Power Market Report, Backup tables and Kenai Peninsula power forecasts. Department of Energy, Juneau, Alaska. 76. State of Alaska Memorandum -Bradley Lake Project, August 25, 1982, Written to Robert Mohn, Director of Engineering, Alaska Power Authority, from George Matz, Program Analyst, Division of Budget and Management, Office of the Governor Memorandum mentions Draft Environmental Impact Statement and General Design Memorandum as well as the Kenai Peninsula Power Supply and Transmission Study and APA Plan of Finance. 77. State of Alaska Memorandum Bradley Lake Hydroelectric Project December 7, 1982 -written to Eric Yould, Executive Director APA from George Matz, Program Analyst, Division of Budget and Management. 78. National Wildlife Refuge, Map Peninsula. Alaska Boundary Series, Kenai 79. Electric Utility Directory Data, Alaska. 1982-83 80. Review of Earthquake Activity and Current Status of Seismic Monitoring in the Region of the Bradley Lake Hydroelectric Project Southern Kenai Peninsula, USGS Alaska: November 30, 1981. 81. REA Financed Generating Plants, U.S. Department of Agriculture, Rural Electrification Admin., January 1983. 82. Chugach Electric Association Annual Report, 1979 & 1981 Pamphlet Issue. 83. Chugach Electric Association Amendment to Prior Agreements for the Sale of Electric Power and Energy and Lease of Facilities, between CEA and Horner Electric Association and Matanuska Electric Association. April 1982. 84. Chugach Electric Association Hourly Logs of Loads, one week in each month of 1982. 85. Chugach Electric Association Plant Operating Reports, REA Form 12, for each generating plant, for each month of 1982. 86. Chugach Electric Association Gas Purchase Agreement with Standard Oil of California, January 1983 .. 87. Chugach Electric Association -ML&P Intertie Energy Rate Schedule, copy of interim interconnection agreement March 1983. 88. Chugach Electric Association Filing for Approval to Revise Fuel & Purchased Power Cost Adjustment Factor, and Non-Firm Power Purchase Rate for Cogenerators and Small Power Producers, April 1983. 89. Chugach Electric Association Tariff Book, May 1983. 90. Chugach Electric Association Filings for Rate Increases, May 1983. Also, generation and sales by month for 1982. See schedules 6 & 7 at end of document. 91. Anchorage Municipal Light & Power Data, including hourly generation (one week/each month 1982), 1982 monthly net generation and peak loads, energy conservation plan, statements on system reliability and margin, fuel contracts, system load projections, loss factors and financial statements for the years ended 1980, 1981 and 1982. 92. Golden Valley Electric Association Data (Fairbanks), including analysis of energy losses, energy conservation program, energy tariffs and rates, financial statements for 1980, 81 and 82, operating reserve requirements, system load estimates, coal purchase agreements, oil purchase agreements, power sales agreements and large commercial customer and power usage data. 93. Land Withdrawal, Federal Register Data, Volume 31 page 4793, Published March 1966. PLATES STERLING HIGHWAY ·."'--. ·y~ ., -.....__ ., ·-~ ...... KEN A I\' PENINSULA / '. ( .?··- -~·., ./. K CARIBOU LAKE 9 , A .. "-A ,~ .. --.. ... ........_ .;<. -... GULF OF ALASKA 20 40 60 80 100MILES 0 ARCTIC OCEAN ~I ~J -4.:~ BERING SEA ' \ ' CANADA 100 0 100 200 300 400 500MILES BRADLEY LAKE HYDROELECTRrC PROJECT ALASKA POWER AUTHORITY . LOCATION MAP & STONE & WEBSTER ENGINEF.RING CORPORATION ANCHORAGE, ALASKA PLATE 1 + + c r·-·-·~·-·--~ ~ i i i i i i + KACB8JIAX. BAY 0 [ r t-I- c..::; f l.:;; [ L L t KACHEMAK BAY MUD FLAT BARGE ACCESS CHANNEL 0 ~ ~ MIDDLE FORK DIVERSION DAM BRADLEY LAKE / 0 '>z1 w w (/) --B UPPER CAMP('\ . QUARRY ~ -~ TO DAM :r;-L) ·.""""-AREA BRADLEY LAKE ,f:>OO~ACCESS ~DAD~ WASr?"'··. NORMAL MAX. WS.EL.1180' UPPER · AREA ~ CAMP ···=-~ c?0\2, .. · ~~\'~ PBRA;~'LAKE HYDROELECTRIC PROJECT r··-~···Y c L ALASKA POWER AUTHORITY GENERAL PLAN A STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA 1000' NOTE: ELEVATIONS SHOWN ARE ON PIDJECT DATUM. MEAN SEA LEVEL DATUM= PROJECT DATUM PLUS 4.02 FT. 0 1000' 2000' 300d 40od SCALE IN FEET PLATE 3 I w z ~ I ~ .. .. + .. "' 2 ,100,000 0 01 ~I ;;; KACHEMAK TIMBER PILE CHAN 8 A y {500FT SPACING! NEL MARKERS 0 0 0 ~ ---~---// _.-~---~ ( t (''~ /.rr-0" _r- NOTE: ELEVATIONS 0 8 ~ ~0 ~ 0 ~ ... ::r 2000 GRAPHic scALE IN FEETnJ ALI>SKA POr:~RELECTRIC PROJECT AUTHORITY ACCESS FACILITIES ~ROJECT DAT~~OWN ARE ON EAN SEA LEV. DATUM PLUS 4~62D~~~M= PROJECT STONE & WE RAM BSTER ENGINEE soo• "c'!."~LTANTS. ONC. ANCHORAGE, AL'1~~ACORPORATION r ~tva Street Anch . ora8e, Alaaka 88502 PLATE 4 SOUTH B5o WEST SMALL BOAT LAUNCH RAMP ------\/ \ \ \ \ \ 250'X76' \ --------- DESIGN BARG.!----\ ( IO'DRAFTJ \ \ \ \ \ \ \ \ \ \ \ \ \ GRAPHIC SCALE 5o--J •• "" DOCK {SEE DETAIL)® FEET DOCK ACCESS ROAD BARGE Off· LOADING EARTH RAMP NOTES "BLPD"= BRADLEY LAKE PROJECT DATUM "FG"=FINISHED GRADE 1'0G11 =0RIGINAL GROUND ELEVATIONS SHOWN ARE ON PROJECT DATUM. . MEAN SEA LEVEL DATUM= PROJECT DATUM PLUS 4.02 FT. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY ACCESS CHANNEl & BARGE BASIN STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA R&M CONSULTANTS, INC. PLATE 5 5024 Cordova Street Anchorage, Alaaka 1111502 n HIGH TIDE I 8~ BLPO) ~zz..2.MLLW APPROX. ORIGINAL GROUND----.......... 17' HULL SARGE, EMPTY @ HIGH TIDE 12' HULL BARGE @LOW TIDE DREDGE LINE 'I 11\J\'1 II . 1'·1 I 1,1:11 !/1:1· 'II ·i I I• •I I ·: 1/11: il I, I I' I 11 " II '1/ I I, II L II U II J U I U li u 2 or:::: ">7-----~ ~ --------,.,.. . \__APPROXIMATE ORIGINAL GROUND 4.4 SMALL BOATS RAMP SECTION A GRAPHIC SCALE \__ 60TTOhl DfttOOfO DUll~ EL -a.!. MLLW l-14 BLPOI 4.4 OFF-L9ADING RAMP SECTION B GRAPHIC SCALE 0 FT. 10 FT. 10 RAMP SURFACE CONCRETE LOGS 193'-9"' 'I • ;,'3·1V2 I --·------~~------·-16 BENTS@ 12'-&"'0.C. ·--.L \ ··-·~··J\ -r-- ! ? •' I' II ~ II I' ,I II r I' d r 'I IJ IJ 'I ~ /I II II ~ II II FENDER PILES UNTREATED, CLASS "a" VERTICAL, 35FT@IO'O.C. I ~~ I I ~ c 'o 'J "' ~ :, A ~ ~ ~ ,, ~ •' r 1 ,I •' r ,, ~ ,, II .. I .(~~' I I I I I I II I ,, II ., '• '• II " '• I' ,, II II II 'I 'J II ,, II ,, II II \i ,, ,, 'I ,, ~ IJ II II Ji II J\ I' lo II ): ~ ;11 ~ A ~ ~ ~ ~ ~ ,, IJ ,, II II I' " ,, II li ,, II II ,, II IJ d I\ ,, " II It ,, ,, I, ,I 'I II I• I' II ~ ~ lr ~ r i ~ ~ r ~ t 'J ,, 1· II ,I ,, Jo ol II ol II ,I ,, ,, ,, II II ,J ,, ,, II " LPILES INDICATED ON BENT •• TYPICAL SPACING. BATTER PILES ARRANGEMENT AS INDICATED STEEL CLEATS, FIVE TOTAL \ w :~P~I~S:.~:~ IIIII 10 0 FT. 20 I -4"X 12" ROUGH DECKING, CCA TREATED ---4" X 12'" STRINGERS@ 1'-0" D.C., CREOSOTE TREATED ~'"--"Ln--"'--"1---IO"XI8" JOISTS@ 2'-0"'0.C., CREOSOTE TREATED I if' X 18" PILE CAP @.12'-6" O.C., CREOSOTE TREATED ·-----~CLASS "B .. CREOSOTE TREATED TIMBER PILES X S6' 12 VERTICAL PILES/BENT 2 BATTER PILES/ BENT ( 4H: 12V BATTER I 4.4 TYPICAL SEC~ION -PILE BENT NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. D GRAPHIC SCALE 10 FT. BRADLEY LAKE HYDROELECfRIC PROJECf ALASKA POWER AUTHORITY DOCK STRUCTURE DETAILS MEAN SEA LEVEL DATUM=PROJECT DATUM PLUS 4.02 FT. STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE,ALASKA RAM CONSULT ANTS, INC. 5024 Cordov•: Street Anchorage, Alaeka 1111502 PLATE 6 BRADLEY LAKE MAXIMUM OPERATING W.S. EL.1180' MINIMUM OPERATING W.S.EL.1080' NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM=PROJECT DATUM PLUS 4.02 FT. :;o· so· '"'' GRAPHIC SCALE 1"s 50'-0" BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY GENERAL ARRANGEMENT DAM, SPILLWAY & FLOW STRUCTURES & STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA PLAfE 7 [EXTREME LOW W. S. EL 1D60' CONCRETE FACE SLAB tr-GROUT CURTAIN I I TOE SLAB ''!\' TOE SLAB "A'= 4' TOE SLAB "B'= 6' TOE SLAB "C'=B' 1P.V.C. GROUT SLEEVE (TYP.) '*9 HOOKED BARS-DRILL & GROUT 3 EACH FOR TOE SLABS "8' &'C' 2 ~~o;~ctOE SLAB ''I<' ® eJ-o· o.c. ZONE 3A BETTER QUARRY MATERIAL COMPACTED ® 16'' LIFTS ZONE 38 POORER QUARRY MATERIAL COMAOCTED ® 18' LIFTS ZONE 2-SELECT COMA!ICTED ROCK ® 3' LIFTS 10 @ 50'= 500' LJ MAXIMUM DAM SECTION SCALE IN FEET . /-CONCRETE ..t' FACE SLABS TOE SLAB TOE SLAB 'c" 1.J ............... ............... -.......... '-----------------_..........-- VIEW LOOKING DOWNSTREAM 0 40' 80' ~--I SCALE IN FEET MASTIC FILLER (TYP. ALL JTS.) 9' NEOP. RUBBER WATER STOP (TYP.) 9'-6' 1 -1 .I "'5®12' PREMOLDED JOINT FILLER (TYP.) NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. ./ 0 2' ... ~P""'§ii_ii"'-~~~1 MEAN SEA LEVEL DATUM= PROJECT DATUM PWS 4.02 FT. SCALE IN fEET OVERSIZED ROCK MAX. W.S. DURING DIVERSION EL.~10~9~6-~6~'JL__,.,"""""""""~~,t(!J.~~~~;h DUMPED IMPERVIOUS---"?"~/ DUMPED 1.5 "'1 UPSTREAM COFFERDAM 0 ,.. e·· SCALE IN FEET #5@12" *'6x6'-0'®6' ... I MASTIC FILLER (TYP. ALL JTS.) FACE OF SLAB I. DOWNSTREAM COFFERDAM __J MAIN RE-BAR #8 41110" E.W 3-3 9" NEOP. RUBBER WATER SlOP (TYP.) PREMOLDED JOINT Fl LLER <TYP.) (DUMPED IMPERVIOUS AND FILTER MATERIAL REPLACED WITH RIP-RAP AFTER CONSTRUCTION) PREMOLDED JOINT FILLER (TYP.) "6x 6'-r::J' ® 6' *'5®12' \ ·o -.o I I--GROUT j CURTAIN '--"'6 til 6' "5®12' 2'-6' 2-2 0 2' 4' ,...,__ I SCAU IN FEET MAIN RE-BAR ""8®10"E.W. 0 -.q.· 9' NEOP. RUBBER WATER SlOP (TYP.) 4-4 0 2' 4' ,...._,._ I SCALE IN FEET 0 2' ... PRI --I SCA1.£1NffET *'9 HOOKED BARS-DRILL & GROUT BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY CONCRETE FACED ROCKFILL DAM SECTIONS & DETAILS STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA PLATE 8 T.O.DAM EL.1194' """\ PMF H.W.EL.1190.6' CREST EL.1180' EL.VARIES T.O.DAM El.1194'"""\ PMF H.W.EL.1190.6' tT-o' CREST 0 ' L ______ _J EU190' CREST EL 1180' 165-o' PMF H.W.EL.1190.6' l 25-o' 'I GROUT ~CURTAIN IIJ ~ ~==============~~~~~~===+==============~ I VIEW LOOKING DOWNSTREAM 0 10' ... e SCALE IN FEET 55-o' 1so·-o· 1-1 0 ,.. ... &,-· I SCALE IN FEET ' ' ' ' \ I I APPROX.SOUND ~ ,,.~~,-~~~~----LL_E_L_1_13 __ 0' ~ 2j / / _____ ___/ 20'-0' 30'-o' / / / 60'-d' 4r:J-o" I ~ I I NOTE: rEU124' ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM= PROJECT DATUM PLUS 4-02 .FT. i BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY SPILLWAY ELEVATION & SECTIONS STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE. ALASKA PLATE 9 1120'- 1110'- 1100'- 1090'- r 1 1' ¢ ROCK SOL TS ® 5' OC. STAG. 15' LONG CELLTIGHT (TYP.) 0 P'i 365' ROCK BOLT ROOF 470' 215' 30' 185' GROUT RING . TUNNEL PLUG LJ & CONTROL GATES DIVERSION TUNNEL SECTION 0 30' 60' l"""''~liii-·-~~iiiiii-~' SCALE IN FEET ..• ;:./f!l:·. FWW SPRING --1----f-_.1 LINE ._ ..... : ..... ,.4 .·.·.,.. .. INV. , EL.1076 215'-o'' INTAKE PORTAL 0 10' ,.. e I SCALE IN FEET 15'-o" .I 1 -1 10' ,.. SCALE IN FEET 30'-o' 3L6"WIDE WALKWAY 185'-o" ) TUNNEL PLUG & CONTROL GATES 10' ,.. I sc:ALEtNFEET GROUT I RING~ 1--l--<[ HYDRAUUC CYLINDERS, 1f'f-o' 2-2 0 10' ,.. e I SCALE IN FEET OPERATOR, & GATES 3'-6"WIDE WALKWAY WATER TIGHT GATE;: SWT COVER TUNNEL 14~o· 14'-o" 5-5 0 10' PI STEEL ACCESS STAIR ,.. I SPRING LINE [SPRING E OUTLET PORTAL 0 ,. 0 N 10' TUNNEL 3-3 oo· SCAL£ IN FEET ,.. I NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM= PROJECT DATUM PLUS 4.02 FT. ' ROCK BOLTS STEEL SETS CONCRETE LINED HORSESHOE n s· to' ,....,... - 0 I"'M• SCALE IN FEET 4-4 10' SCALE IN FEET ,.. I 6" STEEL SETS ®PORTALS ® 41 o.c. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY CONSTRUCTION DIVERSION SECTIONS & DETAILS STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE ALASKA PLATE 10 EL.1212'"""\ __,L___ SPIRAL STAIR HYDRAULIC CYLINDER GATE ~GATE SHAFT I I VENT PIPES rEL 1203' [EQUIPMENT PLATFORM EL1190' [MAINTENANCE PLATFORM EL 1170' lJ .. ~----If-----'2""2'-''!6'----o+f'~12" NOMINAL CONCRETE LINING VENT PIPES OPERATOR ---H--~H----1 HIGH PRESSURE BOLTING MANHOLE POWER ~t::J,,._,N,EL=-t-Jo'---- 1 - 1 0 10' !II)•• EL.1135'"\ tSHAFT ACCESS STAIRWELL '. PLAN-EL.1203' 0 10' 20' !Ill I SCALE IN FEET EL.1030' TRANSVERSE SECTION 0 30' 60' ,.....__- SCALE IN FEET ROCK BOLTS (TYP.) SHAFT INTAKE CHANNEL ~ROCK PLUG COFFERDAM / \ (TO BE REMOVED) eEL 1065' ,--EL 103d ,-EL 1018' LONGITUDINAL SECTION 0 30' 60' ----==a SHAFT GATE SHAFT ACCESS STAIRS TOEL 1172' ~HYDRAULIC PO\NER PACK HIGH POINT EL 1203' REMOVABLE STEEL COVERS PLAN-EL.1053' 0 10' 20' N• I SCAlE IN FEET PLAN -EL.1190' 0 10' e SCALE IN FEET STEEL BOLTING COVERS & CYLINDER SUPPORT . pi!• PLAN -EL.1170' 0 10' 20' N• I SCALE IN FEET SHAFT t--+---+-~ q;_ HYDRAULIC CYLINDER GATE OPERATOR 2-2 , .. VENT PIPES NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM=PROJECT DATUM PLUS 4.02 FT. PLOT PLAN-GATE SHAFT 0 50" 100' IY.---I SCALE IN FEET BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY INTAKE CHANNEL & GATE SHAFT SECTIONS & DETAILS h\ STONE & WEBSTER ENGINEERING CORPOR'ITION ~ ANCHORAGE, ALASKA PLATE 11 8 + "' \"Q 0 0 + @ 7i 0 0 7.1 0 0 + + 0 0 (::: ~ INTAKE DETAIL 0 10' !Ill SCALE IN FEET 1 -1 ,.. N 2-2 ,.. SCALE IN FEET 0 0 + 0 \!l 0 z w CD ...J- \ I ;:!: \ \ z I I 2 I I 0:: I I 0 \ I I 811 '""' ' I "' I I a.l~ 0 :'! TORQUE SHAFT \ BOREHOLE~ FOR RAISE ,~, L=950' HORIZONTAL TUNNEL 0 0 + 0 ~ UPPER BEND DETAIL 0 , .. ,.. P'l I SCALE IN FEET ~TUNNEL 3-3 to' 20' I .01667 SLOPE- 0 0 0 0 + + 0 g ~ ~TUNNEL ~6' SCALE IN FEET I I I I I I 11' 1<1 CONCRETE I I 7i LINED TUNNEL laj\ I I I I 7.1 ~ 0 0 a .I~ 0 0 0 0 + + + 0 0 0 0 \2 0> OJ " <0 TUNNEL PROFILE 500' o' 5oo' 1000' 1500' ~~~~~.iii SCALE: 1'= 5001 TUNNEL 12'' NOMINAL CONCRETE LINING (TYP.) 7-7 o· a· P""""1-I SCALE IN FEET f-'-END OF 2400' i----=L:,-=1:.,4::_.4-':i5;:.:0::.,'c-=--+1' STEEL LINER MAIN TUNNEL --I--..... ~ REINFORCED LOWER BEND DETAIL SCAlE IN FEET AREA W4x13 STEEL SET TUNNEL NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. 10-10 MEAN SEA LEVEL DATUM= PROJECT DATUM PLUS 4.02 FT. 0 •• ,...... - 8 + 0 "' 0 0 + 0 '<t TRh: iSlE; ;T PRESSURE Lll iE t ___ :::-.:_1--_-:-:c PRESSURE LINE J /!J?~-···---- 8 + 0 M ----~ _t-END OF 2400' 6 11 STEEL LINER 0 0 + @ --25001 --2ood "' w z --15001 :J ...J lli f- Ul --10oo' z 8 CD --500' 4 TUNNEL & STEF.L LINER i TUNNEL & STEEL LINER ~~ 6'-8' ' 6-6 0 •• ,...... - 9-9 ,. I SCAlE IN FEET W5x19 STEEL SET I \<--GROUT I ' ' HOLES I 5-5 0 4' 8' P'"""'J-25 SCAlE WfEIET 8-8 SCAlE IN FEET HOOP& LONGITUDINAL STEEL REINFORCING BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY POWER CONDUIT PROFILE & DETAILS STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA PLATE 12 PLOT PLAN-POWERHOUSE SITE 1' i1l ROCK BOLTS ® 5' 0. C. STAG. 15' LONG CELL TIGHT (TYP.) TUNNEL PORTAL 0 ... .... ,...._. __ I SCAlE IN FEET CONCRETE THRUST Eil.OCK 11' i1l STL PENSTOCK ELEVATION-POWERHOUSE, PENSTOCK & PORTAL 0;. il'lil--·~o·~~~,.· ,... SCALEINFEH CO.RAIL, EL.70.5 PLAN POWERHOUSE PENSTOCK & PORTAL 0 10' 20' f.!Nill•ll"iiiiiiiiii~~~~ SCALE IN FEET ACCESS HATCH TO TURBINE CHAMBER rEL.23' HIGH TIDE EL.11.4' EQUIPMENT D'\TA 1 GENERATOR 2 GENERAlOR BREAKER 3 GENERATOR POTENTIAL TRANSFORMER 4 NEUTRAL TRANSFORMER 5 CONTROL ROOM 6 DIESEL GENERAlOR NOTE: ELEVATIONS :SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM=PROJECT DATUM PWS 4.02 FT. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY 90 MW PELTON POWERHOUSE PLANS & SECTIONS-SHT. 1 STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA PLATE 13 40'·0" UNITS UNITS UNIT 2 4:>-o' 55'-o• ~,pi§jl ~ @_] .. :9 1'- 230 N 230 0 17 ,_~~-=~~------------~2~4CJ+4-----+- p1?r, {UNIT 2 I L----- r------------, L----------.J / PLAN-FLOOR EL.23' ;_ ~iil'lil•!!iiiiiii1~··""""""""""~j" UNIT 1 I I 01 I 1281 / I o: L._ ____ ..J._-.J r--,---, ~ : 29o: 1 I I I I o• L _ --1---...J :_o-_: EJ EJ~ 0: @)@)@@) ~ =o -.¢ N 9 'M "' ··~·.:··if->·? I. 11'-6"---+__,_11c..c,_6'_' --+----"'-2"'-0'_-o,_" _ __,+----'-11c..c,_6'_' --t-----'-'11'--~ 6,_"---+--"16,__c_,6'--" --1 PLAN-RUNNER EL.15' , .. ,.. I SCALE IN FEU HIGH TJDE EL.11.4 """\ EL.-61 "") EL.-12'""\ 1 __ 4d-cf_ ______ _ BACK-FILL EL. 21'""\ LONGITUDINAL SECTION SCALE IN FEET EERUNNER TYPICAL SUMP SECTION 0 , .. e EQUIPMENT DATA 7 STATIC EXCITATION 8 GOVERNOR ACCUMULATORS 9 GOVERNOR OIL 10 GREASING UNITS 11 OIL SEF1'.RA TOR 12 OIL TANKS 13 MOTOR CONTROL CEN11ERS 14 SPHERICAL VALVE CONTROL 15 SPHERICAL VALVE ACCUMULATORS 16 UNIT SERVICE WATER PUMPS 17 FIRE PUMPS 18 AIR COMPRESSORS 19 AI_R DRYER 20 AIR TANKS 21 WATER PURIFICATION EQUIPMENT 22 WATER TREATMENT 23 DOMESTIC PUMPS 24 JOCKEY PUMP 25 STATOR SUPPORT COLUMN 26 HOT WATER HEATER 27 480V lDAD CENTER & 480V SWITCHGEAR 28 2-100 GPM DIRTY WATER PUMPS 29 2-500 GPM UNWATERING PUMPS 30 BATTERY ROOM -BACK-FILL EL.-6' NOTE: [T.O.RAIL EL 70.5' ([RUNtJER ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM=PROJECT DATUM PLUS 4.02 FT. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY 90 MW PELTON POWERHOUSE PLANS & SECTIONS-SHT. 2 STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA PLATE 14 TAILRACE FLOW -j---+----!-+"-' leow1"] UNITS 15KV BUS I :1 TO POWERHOUSE rOIL SEI'li.RATOR ----------- o_ ~ (J) Q: ·q: ~ 0 3 Q: Ol g { "' 0 0 0 \_CHAIN-LINK FENCE PLOJ" PLAN-POWERHOUSE SUBSTATION 0 ,.. PI"" SCALE IN FEET 30'WIDE GATE (TYP) WOOD POLE STRUCTURE TYPICAL TRANSMISSION UNE STRUCTURE 0 10' 20' plj I SCALE IN FEET TO SOLDOTNA TO FRITZ CREEK PLOT PLAN -BRADLEY JUCTION 0 20' 40' PI •• I NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM=PROJECT DATUM PLUS 4.02 FT. TO BRADLEY LAKE PROJECT BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY POWERHOUSE SUBSTATION AND BRADLEY JUNCTION ~-STONE & WEBSTER ENGINEERING CORPORATION ~ ANCHORAGE,ALASKA PLATE 15 VERTICAL SCALE: 1 ·~ 5 • HORIZONTAL SCALE: 1 •• 100, E357,000 TYPICAL SECTION 0 ........ SCALE IN FEU , . CONDITIONS IN CONDUIT DISCHARGE =350 CFS CORRESPONDING DEPTH =4 .13 FT VELOCITY = 16.9 FT/SEC STATE-SUPERCRITICAL. NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM MEAN SEA LEVEL DATUM PLUS 4 .of~~M =PROJECT BRADLEY LAKE ALASKA ~OYWDREORELECTRIC PROJECT AUTHORITY MIDDLE FORK DIVERSION PLAN & PROFILE STONE & WEB :~~~OERNAGGINEEERING CORPORATION , ALASKA PLATE 16 SPILLWAY CHANNEL CONCRETE APRON DOWNSTREAM OF lJJW LEVEL OUTLET PLAN-MIDDLE FORK DIVERSION 0 50' 100' l'lo·.---2!!3 SCALE IN FEET INTAKE CENTER LINE NATURAL FLDW MAIN DIVERSION FlDW LINE- 6' CiJ STEEL PIPE 21 1j (; INTAKE & WAL.KWAY BRIDGE DETAIL A SHEET PILE (INTERLOCKS CAULKED) 0 2' 4' ,..._.-_ I SCALE IN FEET MAX.H.W. EL.2210' 72"x 72" SLUICE WITH CIRCULAR WALL THIMBLE-----.11 ~ ~e M I -:'1-~-:-:-J· "1 :rg,.""' _ 1 ''"'"',.. -l \ / I -1----' lDW LEVEL // \ --1 z -~OUTLET /f I \ --1___ ! 1~--------: s·r;J PIPE ROCK LINE /r// 1 1 '>f-r--\T---.J--r--· --1 1 -.....j f - -__j FILL / J_ I I '\ ~ ! / J CONCRETE --// I --......,_ I I 4 I I ~~sE?r'~" '/--T~' . ,---r---T----T----r---Tl-I ~< '-Z._t_L _ _l _ _l_L/ 6 ' ~ P'PE' ' / I ~ ~ I I .J I I I I __./ GROUT CURTAIN WIER KEYED ~ ' ' / -----,, 3 1----" INTO ROCK <" i //I1'2.J : "-, I _L_L_j___L LOCAL KEY TOP OF SHE=:-:-P:_:;: EL.2212'- LOW LEVEL OUTLET .J I / .1--@ SHEET PILE "---1 _L __ L__. CUTOFF WALL ,, VIEW LOOKING DOWNSTREAM 0 10' ,. &•· I 4 JJITAKE fi 2' DEEP KEY CUT INTO SOLID ROCK VIEW LOOKING DOWNSTREAM AT SHEET PILE CUT-OFF WALL 0 10' 2D' e.•• I SCALE IN FEET PZ 3!3 CAULKED INTERLOCKS SHEET PILE CUT OFF WALL NX DRILL HOLES 15' DEEP ® 10' O.C. FOR GROUT CURTAIN NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM= PROJECT DATUM PLUS 4.02 FT. MAX. H.W. EL.2210' 1.5 11/ DAM 1-1 0 10' ,.. e.·-· I 2-2 0 10' 20' )II"" I SCALE IN FEET DAM · rCOMPACTED J 0 .t ROCK FILL ~& (TYP.) "Da '&8Dooc 3-3 . ,.. j:o;po.il'l*·il'l-iiiiiiiii~~~l SCALE IN FEET MAX. H.W. EL.2210' DAM EL.2204' ·o -.q 4-4 ,.. ... I DETAIL B 0 2' 4' paw.++-I SCALE IN FEET DETAIL A SELECT BEDDING MATERIAL BELOW PIPE SPRING LINE SELECT BEDDING MATERIAL BELDW PIPE SPRING LINE CONC. APRON (30'x15') Wz ;;;;<( -'--' oa.. zw ww IIJVJ 4' x 4 CONC BlDCK GROUND LINE w z :J 0 z w Ill, 1% SLOPE BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY MIDDLE FORK DIVERSION ELEVATIONS & DETAILS STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA PLATE 17 .: u 0 0 Q ,~ tO-~ 5- 3 5- 0 2 5- .: u !0- 0 0 2 Q IJJ (!) a: "" :a: 0 <f) 0 I 10- 5- f.---.- f- 1- 1- - - f- -- .....- MAX. WA~ER SUR!ACE ELE!.( 1186.6 'FT.) I / -------v·----..._ __ -----·-f----f.-__ __ .,..----,._ ___ ---I I MAX. SPF INFLOW(I4,400CFS) 1\ 190 1185 lBO 1 \ MAX. SPILLWAY DISCHARGE(I0,400CFS) ' /\""- I 1\ // \ ", "" 1\. J > v // ~ ", ~ ~ ', / ~--;:;.-~ "-......._ ~ / ......... r---._ -- I ---..... ./ -- 2 4 5 6 7 8 9 10 II 12 13 14 15 DURATION (DAYS) STANDARD PROJECT FLOOD m PROBABLE MAX. FLOOD 1NF1.0N (31,300CFSl I I ! i I I I i I ! ! SPILLWAY DE~IGN DISCH.ARGE(22,,700CFS) I (\ I I I\ I \ I I 1\ ! I \ I \ I I J I \ \ I \ \ I I I I ~ \ I I I ~ I ! MAX. WATER SURFACE ELEV. (1190.6 FT.) i I !"' ' ! I /I '\ I I \ \ I I . \ ./ '·-.\ _.v/·' -;~~ !-'-' / I~ '--r---I r~ // "-I • 1-------,, "~ . ' ..... 3// I "-........._ r-__ .J' l 195 190 185 160 2 4 5 6 7 8 9 10 II 12 13 14 15 DURATION (DAYS) PROBABLE MAXIMUM AND SPILLWAY DESIGN FLOODS ~ w w 125 0 !!:, z 0 :::!: ~ ::J ~ ~ 0 SPILLWAY CRESf EL 1180.0 120 .J 1-w 0 0 115 IJJ ., 0 a: n. 1- IJJ 0 MINIMlM OPERATING AN EXISTING LAKE EL.I080.0 110 IJJ II.. !: 10 50 z 0 5 > IJJ ...J IJJ 00 v / 50 / v v 10 9 900 I 8 '"' 250 200 150 1-w w ll.. z 0 i= ~ w .J w PROlLE MALUN JOD ~ -----~ WATER SURFACE EL.1190.6 \'('( 7 -~~ __,/ ..........--/ ~ ,/ ~ y ~ DATA FROM SURVEY FEB. 1980 / AND SOrDINGS AUG. 1980 / v j ! 100 50 J 1 +--t-- I i v i I i I 0 50 100 1!50 200 250 350 400 450 500 550 CAPACITY (IN 1000 ACRE FEET) 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 AREA (IN ACRES) AREA a CAPACITY CURVES ~!ACRE-FEET) CAPACITY (ACRE· FEET) ALTITlDE AREA BELOW LAt<E ABOVE LAKE ALTITUDE AREA BELOW LAKE ABOVE LAKE (FEETI (ACRES SURFACE SURFACE (FEETI (ACRES) SUR FiliCE SURFACE 860 668 263,318 1,060 1,462 31,223 880 829 248,337 1,080.!/ 1,568 0 900 946 230,570 1,100 2,177 36,339 920 991 211,188 1,125 2,808 98,672 940 1,087 190,396 1,150 3,353 175,707 960 1,217 167,338 1,175 3,749 264,502 980 1,290 142,249 1,200 4,106 362,699 1,000 1,349 115,840 1,225 4,544 470,834 1,020 1,393 88,403 .:._ 1,250 41397 588,868 1,040 1,430 60,158 .!/ MINIMUM OPERATING AND EXISTING LAKE SURFACE NOTE: ELEVATIONS SHOWN ~ ON PROJECT DATUM. MEAN SEA LEVEL DATUM=PROJECT DATUM PLUS 4.02 FT. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY PROJECT DESIGN FLOODS AND RESERVOIR AREA-CAPACITY CURVES STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA PLATE 18 R! u 3 0 _.) LJ.. 80 0 70 :2: ...... I 60 ::;:: g ?5 50 a:: w z 40 w 30 1958 1959 1960 1961 1962 1963 1964 1965 1967 1968 1969 1970 1971 TIME STEP IMONTHSI ENERGY GENERATION 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 TIME STEP IMONTHSI RESERVOIR FLUCTUATION Ul 1972 i.97Z ANNUAL ENERGY-GWHRS AVERAGE FIRM SECONDARY 1973 1914 1973 1974 369.2 334.1 35.1 1975 1975 1976 1971 1976 1977 1918 1979 1980 ) 1918 1979 1980 198! 1982 i v 1981 1982 2800 2400 2000 10 20 30 40 50 60 70 80 90 100 PERCENT EXCEEDED MONTHLY RESERVOIR INFLOW DURATION CURVE t30oo .. -----.-----.----.-----.-----.----.-----.----.-----.-----.----.-----.-----r----.-----.----.-----.-----.----.-----.---~.----.-----r----.----. w ~ 2500 );l2000 0 ~ 1500 :3 a. o()1000 ::;:: 9 "-~ 1-w z ------UNREGULATED FLOW -----REGULATED FLOW 1958 1959 1960 DISTRIBUTION RESERVOIR INFLOW 1961 1962 1963 1500- 1250- 1000- UJ LJ.. IJ ::;:: 750- 0 _.) LJ.. 500- 250- 1964 1965 1966 1967 r-- DISTRIBUTION SPILLWAY DISCHARGE r- r- r- - - - 1968 1969 1970 1971 1912 1973 @ LJ.. ~ ::;:: 0 _.) LJ.. TIME STEP (MONTHS) FLOW DISTRIBUTION POWERPLANT DISCHARGE 1974 0:: ~ z 0 ;:: ;l: w ul 1975 1976 1917 1978 1979 MONTHS DISTRIBUTION RESERVOIR ELEVATION 1980 1981 1982 100 75 fi) "-~ 50 ::;:: ~ 25 0 i MAXIMUM AVERAGE MINIMUM . DISTRIBUTION FISH DIVERSION DISCHARGE NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM =PROJECT DATUM PLUS 4.0? FT. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY RESERVOIR REGULATION-90 MW PLANT WITH FISH DIVERSION DISCHARGE ~;.. STONE & WEBSTER ENGINEERING CORPORATION ~ ANCHORAGE,ALASKA PLATE 19 Ul lL lJ :;: 0 ...J lL 28CJO ~ 70 ' ~ 60 ~ b 50 (l: w z w p ~ 1958 1959 1960 1961 1962 1963 1964 1965 1966 1961 1968 1969 1970 1971 TIME STEP (MONTHS l ENERGY GENERATION 1972 ANNUAL ENERGY GWHRS AVERAGE 377.7 FIRM 348.0 SECONDARY 29.7 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 2400 2000 Ul1600 lL lJ :;: ~ 1200 :;:: BOO 51180Tn,-.-"-----,-----.---r~-----.-----,--~-.--,;.--->T.---,_~----.-----.----.---.~-----.-----,-----,-----,----.---r..-----.---,-rr---,..--.~.---r ~ ~ 1160 w (l: ~ 1140 (l: w ~ 1120 (l: j.I: z 1100 ~ g; 1080 0 z w Ul 1958 1959 1960 1961 1962 1963 196-4 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 TIME STEP !MONTHSl RESERVOIR FLUCTUATION t3000TO-----,-----,-----,-----,-----,-----,----,-----,-----~----,-----,-----,----,-----,-----,-----,-----,-----,----,-----,-----~----~----,-----,---, w ~2500 <( -----UNREGULATED FLOW -----REGULATED FLOW I ~2000 0 ,..._ ~1500 ...J Q. o6 1000 :;: 9 lL :;:: ,..._ w z 3000- 2500- 2000- 1500- 1000- 500- 1958 1959 - - - 1960 r- r- 1961 - 1- 0 IJ(FIMIAIMIJIJ AlsloiNIDI MONTHS DISTRIBUTION RESERVOIR INFLOW 1962 1963 1500- 1250- 1000- Ul lL lJ :;: 750- 0 ...J lL 500- 250- 1964 1965 1966 1967 - - DISTRIBUTION SPILLWAY DISCHARGE - - - - - - 1968 1969 1970 1971 1972 1973 v; lL lJ :;: 0 ...J lL TIME STEP I MONTHS l FLOW 1000 750 500 250 o I :. ~ ~ . . . . : ~ ~ : ; : IAIMIJIJ 1 Ais 1o N 1DI MONTHS DISTRIBUTION POWERPLANT DISCHARGE 1974 1975 1180 1160 ~ 1140 z 0 ,..._<(- > 1120 w ...J w (l: ~ 1100 "' w (f) 1976 ·::: ; ~ ~ ; 1917 ::; 1978 1979 1980 ~ 1080---!-'-"!'"'·~·.,• '~'""' ·~7-'""' ;7-;'"'c ~7"'7"-~'7-"'7-- IJ FIMIAIMIJIJIAislol Dl MONTHS DISTRIBUTION RESERVOIR ELEVATION 1981 19!!2 QMAXIMUM ~:~::~~ NOTE: ELEVATIONS SHOWN ARE ON PROJECT DATUM. MEAN SEA LEVEL DATUM=PROJECT DATUM PLUS 4.02 FT. 400 10 20 30 40 50 60 70 80 90 100 PERCENT EXCEEDED MONTHLY RESERVOIR INFLOW DURATION CURVE BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY RESERVOIR REGULATION-90MW PLANT WITHOUT FISH DIVERSION DISCHARGE ~ STONE & WEBSTER ENGINEERING CORPORATION ~ ANCHORAGE. ALASKA PLATE 20 1196~----~----r-----r-----r-----.-----~----.-----.-----.-----.-----,------r----. 1194~----+-----~----~-----+----~~----+-----~-----+-----+----~~----+-----~----~ ::; ~ 1192~----~-----4------+-----~------~----~-----4~----+-----~----~~----~----~----~ 0 ... ~ MAX RES EL 1190.6 ~ 1190 ........ 0'1---+-----l ~ ~ g 5 ~ ~ ~ 11881-----+------l------+------+------I-----+V'------li"""C,... ......... ""'---t------+------+----+ ~il---+-----l z ~ 0 ~ X ~ ~ ~ ~ 1186~--~---4---+---~-~~F---~--~---+---~--~~---r~'l--4---~ i J,~// ~ « ~--~----~~~~----~--~----+----+----+---~----r----+·~--~--~ ~1184 v -~ ·,Rv/ ~ 11800 2 4 6 a 10 12 14 16 18 20 22 24 DISCHARGE (1000 X CFS) SPILLWAY RATING CURVE 1092~--~-----r----~----~--~-----r----,-----r----,-----.!.-_---_.-l--~ MAX TW 10906 I~0~----~----+-----+----~~----+-----~-----+-----4------~---+-~~~~~~0+-~ I ...,.......V ~-~V ~ ~---4-----+----4-----~---4-----+----~----~~~~4-----~---;-~~ 108e I ~~ e- V Ill 1088·~--~---+----~--4----+----~~~4----r--~----+----r~~ == v~ 0 ~ ::; ~ ~ ~ 0 ~ ::; b 1084~----+----~-----+-----4~~--t-----1------r-----t---~r-----t------ril----~ // ~ « ~ ~ ~ ~ 1082~--~--~---~~-~--~~--~--~~--+----+--~~---+~1---- ; i~ w ! 1080 -MAXDIV~ ~ 1078 I ~~ t----+---+---+----+---t----+---+---t----+----1 u. zw « ~"' ~ 1076/ il ; ~~ 2:::; 1074~---+--0 ~~--~-----+-----+-----+----~----4-----+-----~----~---4 I == 1072~----+-----+-----+-----+-----+-----4-----1-----1-----1-----4-----~-----1 1070~----+----~-----+-----4------t-----1------r-----+----~------~----4------1 I06B0!---~2~--~4~--~6---8~--~I0~--~12~--~14~--~~--~1~8--~20~--2~2~--~24 DISCHARGE (1000 X CFS) UPPER BRADLEY RIVER TAILWATER RATING CURVE (POST PROJECT CONDITIONS) 26 1100 ,.------.-----..,.------,-----.------, 1098 1---------+-------t------+-------+-v---+---il 1 o96 ~---~M~A~XI~M~U~M~P~O~O~L~E~L~I~09~6~i.sl~------1 I/? 10941-----+-----+------t/+---:- ~ I "' ~ 1092 !~ * v 0 ~ 10901----~--tl ir--i I == 10881------+-~ ~ I i 1086 ~~----+-~-~~t---~---4 - - 1180 1170 1160 « 10841--;+-+---"'-l~i--~ -1150 -1140 DAYS "" I /'~---+--+------1 IOBOHL----+-~--+-----+-----t-----4 ./v - - - - 1018 .. ~--~~------2~----~3~----4~--~ 5 DISCHARGE 1000 CFS DIVERSION TUNNEL RATING CURVES 15 _39 HT ~_.!..1 --"2=.___,3~_:.4!___,5~__,6~---'7~__,8~__:;9~___,10,___--"11~~12:.__.!!:13~--'-'14~-"'15~-"16"---1!.!7 _ __,;18~-"1"'9--"2"-0--jii.3T HT SPRING TIDES 1130 1120 1110 1100 1090 1080 8.80MHHWr---fl-ft--tr-frfrfrH-frH-fl-H-.-Jt------------------------------------.--4r--~---141BMHHW 7.99 MHW 3.87MHW NEAP TIDES 4.021-ti-H-H-+++ttt-ttH-trH-ttll+-llt-t++t+H1Ht-tt~Hf-n,.-H-it-tt-tt-tr-lt-ti-H--+t-tt-tt-+t+ttrtt-H--Io.oo ::; ~ ~ Q b w a o.oor-tttttt+-hrHrrttrrtttttttttttttttt+MHrr~~~-t1-t1-t1-t1++++t++++-l-+++++-t1++++++++--l-4o2MsL ~ ~ u -8.00 MLW l--tHHHr-tt--lt-tr-trtt--tr+t-tr+t.JL-tr--tr-*----"--------ll---tt--~+-_JH-~+---lt--4-12.02 MUV ~ -9.61 MLLW I-~HH~-\t--l+-f+--trtt--II-+I-...::...+I---H---II-------------...II...-~IJ--H-~I!--ll---4-13.63 MLLW ;:: i 15.61LT~================jt==~=========================================================1 1--19.63LT MAY TIDAL RATING CURVES (SEE NOTE I) w w !: ... X "' j;j J: w 0 ;::: ::; ~ ~ Q ... !d 6 IE ~ w w ... -z 0 ~ "" w ~ w « ~ a: w w "' a: NOTES I. TIDE HEIGHTS BELOW EL 6.0 PROJECT DATUM WILL NOT AFFECT POWERPLANT OPERATION. IN THOSE INSTANCES WHERE TIDE HEIGHT EXCEEDS EL 6.0 A TAILWATER DEPRESSION SYSTEM WILL MAINTAIN WATER LEVELS WITHIN THE DRAFT TUBE BELOW EL 6.0. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY RATING CURVES A STONE & WEBSTER ENGINEERING CORPORATION ANCHORAGE, ALASKA PLATE 21 115KV LINES TO BRADLEY JUNCTION 3 1 • I ccv~~l 115KV __/I SUBSTATION I "' € "'" t r 1200A. TO PERMANENT CAMP OCB I I I I ~--------~--------~ 1200A I L.A. CCVT <>---ill CCVT I ~u~ I Jl OA/FA/FA 33.8/45/56.3 MVA I ('f rn 115KV GRY.-13.8KV;3111,60HZ * ('f ll L---~-~-----------------~ 1 2 1 2 -<B~>---<BE--«::»-?>-- P.T. P.T. ~ 3000 A. ~ 3000 A. 3 3 -<B E-;r:::n-7; P.T. SURGE PROT. 3 3 ~~~ -<B~ P.T. EXC ~""'"'""· ... , ... 1J.8KV,I,60HZ o.ll5 P.r.----../ SURGE PROT. ~~~ EXC TO FRITZ CREEK BRADLEY JUNCTION . T / T • N.O. N.C.~ (N.C. ~ TO BRADLEY LAKE LOAD CENTER UNIT SUBSTATION TO SOLDOTNA ,----------------, I I I I I I I I I I I I I I I 4 P.T. CL UW 750 KVA T 13.8 KV-480V 3 ... 60HZ t ) 1600A. ~ , CL I I I I I I u. ..u 750 KVA I T 13.8 KV-480V I 3 ... 60HZ P.T. I 2 ~ I it: I I I) )._ I 1600A ~ 4 ~ I I I 1aoo 1- 1 800A il') il') 800:ooA il') il') 800A I I f f f f ! L ________________ ~ P.T. If i 250 KVA 480V 3JJ 60HZ. ) 800A BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY MAIN ONE LINE DIAGRAM J>\ STONE & WEBSTER ENGINEERING CORPORATION ~ ANCHORAGE, ALASKA PLATE 22 1984 1985 1986 1987 1988 JAN I FEB I MAR APR I MAY I JUN JUL I AUG I SEP OCT I NOV I DEC JAN I FEB I MAR APR I MAY I JUN JUL I AUG I SEP OCT I NOV I DEC JAN I FEB I MAR APR I MAYj_ JUN JUL I AUG I SEP OCT I NOV I DEC JAN I FEB I MAR APR I MAY I JUN JUL I AUG I SEP OCT I NOV I DEC JAN I FEB I MAR APR I MAY I JUN JUL I AUG I SEP OCT I NOV I DEC f: FERC LICENSE APPLICATION PROCESSING & SUPPORT ACTIVITY ( -o.) FERC AWARD l I I I I I l r~r-----------P~R~E~PA=R=E~A~PP~l~IC=A~TI~ON~&~O~B~TA~IN~O~T=H~ER~l~IC~E~NC~E~S~&~P~E=R=MI~TS~--------~~~~~------------------------------------------------------~CO=N=TI=NU~E~O~M~O~NIT~O=R=IN~G--~F~E=RC~&~A~GE=N=CY~CO=O=R~OI=NA=T=IO=N~T=HR=O~UG=H~O~UT~PR= I ( I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I : . ,r------------------------------------------------------------------------------..0 MIDDLE FORK DIVERSION o-----------------------, : ! l ( co~~1~~~WoN c~~'n~WoN 1 ! : l :,------~---------------------------------------------------------------------------------------------------~! : ! l r 1 r ~ ! I I : t._ SPR..LWAY I : I ~ COc"JJf~_fJ!rON ~ §liNTR~~1,1~ACT '-----,~-~ (----------------------------------------o(J Q----------..~ ~ ~ ~ !.. DAM, TUNNELS, DIVERSION, ROADS, & BID EVAL !.!." COFFER ) ' ' ) I !v~~----~~c~o~N~n~·~~~T~w~N~r~M~~~~~~~s~-~rn~c~~~~~·~~~·~&wo~•~~~~~--~~-od0-~_,_0_"_8_0bo---~~~-&oF~~~0~J----~"~~=M=c='=~=~~·="-----~~ ~M~~ ~~&~~;-a ~· -----------------------------------~----~, ~~ ~~~-~O \ I I I I l I \ ~"[) CONSTRUCTION SUPPORT FACILITIES Q----.. I : I l I I .. L INTAKE TUNNEL I : l l ORU & BLAST 1 '-------~--, : l : 1.._ pJ'JE'rt~~~~~S~X~~~~ T1oN INITIAL TUNNEL SECTION ') : ~ II: "[) Cl<~o(}---------()_i Ill ! : l._ I I RAISE BORE 1..,. INT~~~ffe:R~HAFT SH~~fC~~~EK~Nlfb~~EL, EXCAVATE&: BREACH J ~ '() TUNNEL BORING MACHINE ITBMl -F' ABRICATE &: DEliVER «) 0 POWER TUNNEL EXCAVATION ITBUJ Q INCUNED SHAFT ~ GATE SHAFT &: PORTAL Q ROCK PLUG (Y / ~~~ ~~~ 1 1 ( .. STAll & TEST ·: ~~~ : \.'()GATE SHAFT EQPT (}) : DEMOBILIZ~ ' I l CONCRETE LINE POWER ) I : "{] TUNNEL TO STEEL UNER 0 STEEL LINER &: CONCRETE (}. .-/ : 1 ') I : I I I I I I I I I I I I l I I I I I I I I I I I l'---------------------------------------------------------------,. (r-------------------o{Y) PENSTOCK l ,(} 1 Rl: ONTRACT 1 1 r----o·OWERHO~S. SWITCHYAROo--------------------------r POWERHOUSE AWARD : ( l i CONTRACT POWERHOUSE CONTRACTOR I I STEEL I :'--------------------~-·--·--·-t(r--~---------~---------~--~PO=W~E:RH=O=U~SE~E~N=GI=NE:E=RI:NG~&~O=E=SIG=N~-------~~~~--~-------(yOU~T-F~OR __ BD~·~Lr~B=ID~E=VA:l~~·~A~T~~=IA~l~PR~O~CUR~DE~NT~&~~=·=U~Z=E~~K)~)~c=O~NC~R~ET~E~W~O~R~K~'~~lUP~E-RS~T-RU~C~~i~)E----'~~~5~~~~~~~~i~~~t~T~~l~~~~~~~~~----~l~~n 1 (t(J ( ' ' ~ o (~ ~)(~ r~ l l l : l l I I I I I 1 I I I l \.!(l UNIT 11NSTALL TURBINE & GENERATOR ~START UP l l l : : : l (~ ( (~ (""' UNIT 1 COMMERCIAL OPERATION I I : l l l l : l I I I I I I : : l I I : \.__., UNIT 2 INSTALL TURBINE ct GENERATOR l,~ STAAT UP ) : l · 1 , 1 1 I l ~~ (r-u I \.J -1,J I I I I I 1 I I : \p~EQPT I ,?IAUT~ORIZATION : I I I 1 I I l cWvREB~~~s?~~~R~l~~~S \ AWARO : ~A~}B~~R,_1~$9E : ! l : l : : 1'\~NGINEERING &: DESIG~OUT FOR BID~ BID EVAL\ MODEL TESTS & MANUFACTURER'S DRAWINGS l, J. I TURBINES, GENERATORS, GOVERNORS, SPH VALVES-FABRICATE&: DELIVER /... : l._ 1.._ I l"-' '-' .g, ( B;EOPT I I I : l I AWARD I : : l I ~·~~:r~P=OW~E~R~HO~U~SE~C~R~AN=E~E~NG~~~··~""~G~&~O~E~~~~~~~UT~FO~R~B~IDZ)~~B~IO~E~V~~~O~~F=AC=ru~R~E=R'~S~OR~A~M~N~GS{)~)--------------------~P~O~W£~R~HO~U~S~E~C~RA~~~E_:-~F~AB~R~IC=AT~E~&~OE~l~IV~ER~--~~~--------------1rr11 l I "-' 'f' I I : I I l I ~I '--------------------------------------------0~--A-UX_Il_IA::: .. Ac:YNC:If'-'fo"C.\'"fu"'N~eo~~o;fS::_&!eOR~Ei:;!~:C~T::<G~::_ICO:::_,lD::o~~'-'~'-IP-NE_H_T __ _,rv_) AUXILARY MECHANICAL &: ELECTRICAL EQUIPMENT -FABRICATE &: DELIVER l, ll.f) ~ I ~ (» ~ LJ ! : AUXILARY MECHANICAL &: ELECTRICAL EQUIPMENT ~ l f'-----------~~--------------~EN"Gc:IN~EE~R:ciN~G,_,DC:E~SIG~N~&~P~RO~C~UR~E~ME~N~T------------~'~ : I I I I I I I I UNIT 2 COMMERCIAL OPERATION PROJECT COMPLETE START FINISH NQr'---•'--c'-'T'-IV-'IT_r ___ NQE Q -ENGINEERING @ -ISSUE PURCHASE ORDER 0 -EOPT DELIVERY TO FIELD 0-CONSTRUCTION OR START UP I I I I I I I I I I BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY I I I I I I I I I I I ~ I I CONTRACT I I AWARD I I I ''--------------------------------------------------------~------~~:r----------~T~RA~N=S=MI=SS=IO=N~l=IN=E~E=NG=IN=Ec:ER=IN=G~&~OE=S=IG=N----~-----{}COU=T~F~~~·=IO~{}~BmO~E~VA~l~~=O~~~f}--~TR~A~NS=M=IS=SI=ON~li=NE~C=O=N=ST~R~UC~T=IO~N--~~jr--------------- 1984 1985 1986 1987 1988 PROJECT SCHEDULE STONE & WEBSTER E"'GINEERING CORPORATION ANCHORAGE, ALASKA PLATE 23