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Stetson Creek Diversion and Cooper Lake Dam Facilities Project Feasibility Report - Mar 2011 - REF Grant 7040005
STETSON CREEK DIVERSION AND COOPER LAKE DAM FACILITIES FEASIBILITY REPORT FINAL REPORT MARCH 14, 2011 Prepared by: Stetson Creek Diversion and Cooper Lake Dam Facilities Page i Feasibility Report – Final 14 March 2011 TABLE OF CONTENTS ACRONYMS AND ABBREVIATIONS ......................................................................................v DISCLAIMER.............................................................................................................................. vi EXECUTIVE SUMMARY .................................................................................................... ES-1 COPYRIGHT .............................................................................................................................VII 1.0 INTRODUCTION............................................................................................................. 1-1 1.1 Background ................................................................................................................ 1-1 1.2 Existing Project Layout .............................................................................................. 1-1 1.3 Proposed Modifications ............................................................................................. 1-1 1.4 Other Design Alternatives.......................................................................................... 1-2 1.4.1 Reducing Maximum Diverted Flow from 110 cfs to 70 cfs .......................... 1-2 1.4.2 Hydroelectric / Pumped Flow Option ............................................................ 1-2 1.4.3 Pumped Flow Option ..................................................................................... 1-7 2.0 FIELD INVESTIGATIONS ............................................................................................ 2-1 2.1 Diversion Structure .................................................................................................... 2-1 2.1.1 Diversion Pipeline and Pipeline ..................................................................... 2-1 2.1.2 Cooper Lake Dam .......................................................................................... 2-1 2.1.3 Cooper Lake Dam Drilling ............................................................................ 2-2 2.1.4 Borrow Areas ................................................................................................. 2-2 2.2 Analysis of 2009 Field Investigations ....................................................................... 2-2 2.2.1 Diversion Dam ............................................................................................... 2-2 2.2.2 Diversion Pipeline .......................................................................................... 2-3 2.2.3 Cooper Lake Dam .......................................................................................... 2-4 2.2.4 Borrow Areas ................................................................................................. 2-5 2.3 2010 Additional Field Investigations ......................................................................... 2-6 2.3.1 Diversion Dam ............................................................................................... 2-6 2.3.2 Diversion Pipeline Alignment........................................................................ 2-6 2.3.3 Siphon Outlet Facilities.................................................................................. 2-7 3.0 PROJECT FEASIBILITY ............................................................................................... 3-1 3.1 Design Criteria and Assumptions .............................................................................. 3-1 3.1.1 Design Criteria and Project Facts .................................................................. 3-1 3.1.2 Assumptions ................................................................................................... 3-3 3.2 Stetson Creek Diversion Structure ............................................................................. 3-3 3.2.1 Hydrology ...................................................................................................... 3-3 3.2.2 Hydraulics ...................................................................................................... 3-5 3.2.3 Sizing and Layout .......................................................................................... 3-9 3.2.4 Flow Control and Monitoring ...................................................................... 3-10 3.2.5 Access .......................................................................................................... 3-10 3.2.6 Construction ................................................................................................. 3-10 3.2.7 Maintenance ................................................................................................. 3-11 3.3 Stetson Creek Diversion Pipeline ............................................................................ 3-11 3.3.1 Pipeline Hydraulics ...................................................................................... 3-11 3.3.2 Pipeline Materials and Routing .................................................................... 3-12 Stetson Creek Diversion and Cooper Lake Dam Facilities Page ii Feasibility Report – Final 14 March 2011 3.3.3 Flow Control and Monitoring ...................................................................... 3-12 3.3.4 Pipeline Bench/Pipeline Construction Access ............................................. 3-12 3.3.5 Spillway Bridge ........................................................................................... 3-13 3.3.6 Construction ................................................................................................. 3-13 3.3.7 Maintenance ................................................................................................. 3-13 3.4 Stetson Creek Diversion Outfall .............................................................................. 3-14 3.4.1 Hydraulics and Siting ................................................................................... 3-14 3.4.2 Energy Dissipation and Flow Diffusion ...................................................... 3-14 3.4.3 Construction ................................................................................................. 3-14 3.4.4 Maintenance ................................................................................................. 3-15 3.5 Cooper Lake Dam Outlet Works ............................................................................. 3-15 3.5.1 Hydrology and Hydraulics ........................................................................... 3-15 3.5.2 Routing Alternatives .................................................................................... 3-16 3.5.3 Intake............................................................................................................ 3-19 3.5.4 Outlet............................................................................................................ 3-20 3.5.5 Flow Control and Monitoring ...................................................................... 3-20 3.5.6 Construction ................................................................................................. 3-21 3.5.7 Maintenance ................................................................................................. 3-22 3.6 Site Access ............................................................................................................... 3-23 4.0 CONSTRUCTION SCHEDULE AND CONTRACTING APPROACH .................... 4-1 4.1 Issues and Constraints ................................................................................................ 4-1 4.1.1 Construction Staging ...................................................................................... 4-1 4.1.2 Access Considerations and Laydown Areas .................................................. 4-1 4.1.3 Schedule Constraints ...................................................................................... 4-2 4.1.4 Environmental Considerations ....................................................................... 4-2 4.1.5 Weather Considerations ................................................................................. 4-3 4.2 Number of Contracts and Contractors ....................................................................... 4-3 4.3 Engineering Design Responsibilities ......................................................................... 4-4 4.4 Recommended Contracting Approach ....................................................................... 4-5 4.5 Schedule ..................................................................................................................... 4-5 5.0 PERMITTING .................................................................................................................. 5-1 5.1 Required Plans and Permits ....................................................................................... 5-1 5.1.1 U.S. Army Corps of Engineers 404 Permit.................................................... 5-2 5.1.2 401 Water Quality Certification ..................................................................... 5-4 5.1.3 Storm Water Pollution Discharge Elimination System Permit (402 Clean Water Act) ........................................................................................... 5-4 5.1.4 Fish Habitat Permit ........................................................................................ 5-4 5.1.5 Water Rights .................................................................................................. 5-4 5.1.6 Consistency Determination under Alaska Coastal Zone Management Program .......................................................................................................... 5-5 5.2 Permitting Timeline ................................................................................................... 5-5 5.3 Completion Time Extension ...................................................................................... 5-6 6.0 OPINION OF PROBABLE CONSTRUCTION COST (OPCC) ................................. 6-1 6.1 Basis of Estimate........................................................................................................ 6-1 6.2 Conceptual Design Information ................................................................................. 6-1 Stetson Creek Diversion and Cooper Lake Dam Facilities Page iii Feasibility Report – Final 14 March 2011 6.3 Assumptions ............................................................................................................... 6-2 6.4 Basis of Quantities ..................................................................................................... 6-2 6.5 Basis of Pricing .......................................................................................................... 6-2 6.5.1 Resource Rates ............................................................................................... 6-2 6.5.2 Quantities ....................................................................................................... 6-2 6.5.3 Direct Costs .................................................................................................... 6-2 6.5.4 Contractor and Subcontractor Indirect Costs ................................................. 6-2 6.5.5 Contractor and Subcontractor Margin (Contingency, Overhead & Profit) ............................................................................................................. 6-3 6.6 OPCC Summary......................................................................................................... 6-3 6.7 Overall Project Cost ................................................................................................... 6-3 6.8 Comparison of 2004 EPC and 2010 OPCC ............................................................... 6-3 6.8.1 Cost Estimation Methodology ....................................................................... 6-3 6.8.2 Comparison Methodology ............................................................................. 6-7 6.8.3 Summary of Cost Impacts .............................................................................. 6-8 TABLES Table 1-1 Recorded Streamflow (ac-ft) on Stetson Creek at USGS Gage 15260500 .......... 1-2 Table 1-2 Minimum Instream Flows (cfs) ........................................................................... 1-3 Table 1-3 Stetson Creek Diversion Dam to Cooper Lake Pipeline ...................................... 1-3 Table 1-4 Powerhouse Results – Generation All Year ......................................................... 1-4 Table 1-5 Powerhouse Results – No Generation December - April .................................... 1-5 Table 1-6 Powerhouse/Pumping Net Generation (MWh) 110 cfs Maximum Pipeline Flow and 50 cfs Maximum Powerhouse Flow .................................................... 1-5 Table 1-7 Powerhouse/Pumping Net Generation (MWh) 70 cfs Maximum Pipeline Flow and 40 cfs Maximum Powerhouse Flow .................................................... 1-5 Table 1-8 Powerhouse/Pumping Net Generation (MWh) 40 cfs Maximum Pipeline Flow and 20 cfs Maximum Powerhouse Flow .................................................... 1-5 Table 1-9 Powerhouse Results – Increased Pipe Diameter – Generation All Year ............. 1-6 Table 1-10 Powerhouse Results Increased Pipe Diameter – No Generation December - April ................................................................................................................... 1-6 Table 3-1 Estimated, Average Monthly Stetson Creek Flow at USGS Gage 15260500 and Diversion Dam Site ...................................................................... 3-4 Table 3-2 Average Monthly Diversion Flows ...................................................................... 3-6 Table 3-3 Targeted Cooper Lake Release Flow, Estimated Average Diversion Flows, and Estimated Cooper Lake Drawdown/Refill .................................................. 3-16 Table 6-1 2010 Opinion of Probable Construction Cost for Option 1 – Gravity Option .................................................................................................................. 6-4 Table 6-2 2011 Opinion of Probable Construction Cost for Option 2 – Siphon Option ...... 6-5 Table 6-3 Estimated Overall Project Cost – Gravity Option (2010) .................................... 6-6 Table 6-4 Estimated Overall Project Cost – Siphon Option (2011) ..................................... 6-6 Stetson Creek Diversion and Cooper Lake Dam Facilities Page iv Feasibility Report – Final 14 March 2011 PHOTOS Photo 3-1 Diversion Dam Site Alternative 1 – Elevation 1,304 .......................................... 3-8 Photo 3-2 Diversion Dam Site Alternative 2 – Elevation 1,424 .......................................... 3-8 GRAPHS Graph 3-1 Estimated, Post-Cooper Lake Dam, Stetson Creek Flow Exceedence Curve at USGS Gage 15260500 .......................................................................... 3-5 Graph 3-2 Cooper Lake Temperature Profiles (2002-2003) Plotted on Average Historical Cooper Lake Levels .......................................................................... 3-17 Graph 3-3 Post-Construction Net Inflow to Cooper Lake versus Historic Lake Levels ..... 3-17 Graph 3-4 Post-Construction Target Discharge from Cooper Lake to Cooper Creek versus Historic Lake Levels ............................................................................... 3-18 2010 FIGURES Figure F-1 Location Plan Figure F-2 Civil – Site Plan Figure F-3 Civil – Cooper Lake Dam Outlet Works – Plan and Section Figure F-4 Civil – Cooper Lake Dam Outlet Works Gravity Option – Profile and Sections Figure F-5 Civil – Cooper Lake Dam Outlet Works Siphon Option – Profile and Sections Figure F-6 Civil – Diversion Dam and Intake – Plan, Elevation and Section Figure F-7 Civil – Diversion Pipeline STA 0+00 – STA 10+00 – Plan and Profile Figure F-8 Civil – Diversion Pipeline STA 10+00 – STA 25+00 – Plan and Profile Figure F-9 Civil – Diversion Pipeline STA 25+00 – STA 40+00 – Plan and Profile Figure F-10 Civil – Diversion Pipeline STA 40+00 – STA 55+00 – Plan and Profile Figure F-11 Civil – Diversion Pipeline STA 55+00 – STA 70+00 – Plan and Profile Figure F-12 Civil – Diversion Pipeline STA 70+00 – STA 85+00 – Plan and Profile Figure F-13 Civil – Diversion Pipeline STA 85+00 – STA 100+00 – Plan and Profile Figure F-14 Civil – Diversion Pipeline STA 100+00 – STA 115+00 – Plan and Profile Figure F-15 Civil – Diversion Pipeline STA 115+00 – STA 123+19 – Plan and Profile Figure F-16 Civil – Spillway Bridge – Plan and Profile Stetson Creek Diversion and Cooper Lake Dam Facilities Page v Feasibility Report – Final 14 March 2011 2011 FIGURES Figure F-1 Location Plan Figure F-2 Civil – Site Plan Figure F-3 Civil – Cooper Lake Dam Outlet Works – Plan Figure F-4 Civil – Cooper Lake Dam Outlet Works – Profile Figure F-5 Civil – Cooper Lake Dam Outlet Works – Sections Figure F-6 Civil – Diversion Dam and Intake – Plan and Elevation Figure F-7 Civil – Diversion Pipeline STA 0+00 – STA 10+00 – Plan and Profile Figure F-8 Civil – Diversion Pipeline STA 10+00 – STA 25+00 – Plan and Profile Figure F-9 Civil – Diversion Pipeline STA 25+00 – STA 40+00 – Plan and Profile Figure F-10 Civil – Diversion Pipeline STA 40+00 – STA 55+00 – Plan and Profile Figure F-11 Civil – Diversion Pipeline STA 55+00 – STA 70+00 – Plan and Profile Figure F-12 Civil – Diversion Pipeline STA 70+00 – STA 85+00 – Plan and Profile Figure F-13 Civil – Diversion Pipeline STA 85+00 – STA 100+00 – Plan and Profile Figure F-14 Civil – Diversion Pipeline STA 100+00 – STA 110+00 – Plan and Profile Figure F-15 Civil – Diversion Pipeline STA 110+00 – STA 116+71 – Plan and Profile Figure F-16 Civil – Diversion Pipeline – Sections Figure F-17 Schedule APPENDICES Appendix A – Geotechnical Feasibility Study - Final Draft Report Appendix B – Opinions of Probable Construction Cost Appendix C – Avalanche Report Appendix D – Dive Logs Appendix E – Comparison of 2004 EPC and 2010 OPCC Appendix F – Report of Geotechnical Engineering Services – Revised Draft Report Stetson Creek Diversion and Cooper Lake Dam Facilities Page vi Feasibility Report – Final 14 March 2011 ACRONYMS AND ABBREVIATIONS % percent ac-ft acre-feet ACMP Alaska Coastal Management Program ADEC Alaska Department of Environmental Conservation ADF&G Alaska Department of Fish and Game ADNR Alaska Department of Natural Resources ADOT&PF Alaska Department of Transportation and Public Facilities bgs below the ground surface CAPA Central Alaska Power Association cfs cubic feet per second Chugach Chugach Electric Association Corps U.S. Army Corps of Engineers CPQ Coastal Project Questionnaire EFH Essential Fish Habitat EL elevation EPA U.S. Environmental Protection Agency EPC Engineer-Procure-Construct FERC Federal Energy Regulatory Commission fps feet per second Gravity Option Gravity Outlet Facility Option (see paragraph 3.5.2.1) H horizontal HDPE high-density polyethylene IC instrumentation and controls ID inside diameter kV kilovolt M magnitude MIF minimum instream flow MWH MWH Americas, Inc. MWh megawatt hours my million years before present NEPA National Environmental Policy Act OPCC Opinion of Probable Construction Cost PME Potential Cooper Creek Protection, Mitigation and Enhancement Measures Project Stetson Creek Diversion and Cooper Lake Dam Facilities Project PLC programmable logic controller psf pounds per square foot PSV pressure sustaining valve Siphon Option Spillway Siphon Outlet Facility Option (see paragraph 3.5.2.2) SWPPP Stormwater Pollution Prevention Plan USGS U.S. Geologic Survey V vertical WSEL water surface elevation Stetson Creek Diversion and Cooper Lake Dam Facilities Page vii Feasibility Report – Final 14 March 2011 DISCLAIMER This report has been prepared in accordance with the terms set out in the contract between Chugach Electric Association, Inc. (Chugach) and MWH. Some of the information, evaluations, and opinions contained herein were based on data and results prepared by or obtained from other parties not under the direct control of MWH. In preparing this report, MWH made use of, and relied upon, data, drawings, analyses, reports, memos, letters, e-mails, and other information provided by others. While MWH did not perform independent investigations or analyses to determine the validity or suitability of such items and information, MWH did comply with applicable industry standards in MWH’s: (i) evaluation and use of any third party data, drawings, analyses, reports, memos, letters, emails, and other information, and (ii) the generation of the information, evaluations and opinions contained herein. Therefore, neither MWH nor Chugach or any person acting on their behalf, may make any warranty, expressed or implied, or assume any liability with respect to the use of any information, method, product, process, or statement contained in this report. Any recipient of this report, including Chugach, or any others, by their receipt and use of this report, hereby releases MWH and Chugach from any liability for direct, indirect, or consequential loss or damage, whether arising in contract, tort (including negligence, but excluding gross negligence), strict liability, or otherwise. MWH was neither requested to perform nor has performed environmental or regulatory investigations or assessments in connection with the facilities described in this report. Also, MWH was neither requested to, nor has performed, any economic analyses or detailed evaluation of any permits or licenses. The content of this report is governed by confidentiality clauses in the contract between MWH and the Client. The contents of this document may not be disclosed to other parties in a manner not consistent with the terms of the confidentiality clauses of the contract. COPYRIGHT © 2011 Chugach Electric Association, Inc., Anchorage, Alaska. All rights reserved under U.S. and foreign law, treaties and conventions. The attached work was specifically ordered under an agreement with Chugach Electric Association, Inc., Anchorage, Alaska. All rights in the various work produced for or under this agreement, including but not limited to study plans and study results, drafts, charts, graphs and other forms of presentation, summaries and final work products, are the exclusive property of Chugach Electric Association. Stetson Creek Diversion and Cooper Lake Dam Facilities Page viii Feasibility Report – Final 14 March 2011 PROJECT TEAM The following individuals were the key personnel involved in the preparation of the Stetson Creek Diversion and Cooper Lake Dam Facilities Feasibility Report: Trey Acteson – Chugach Project Manager Peter Poray – Chugach Project Engineer Brian Miskill – MWH Project Manager Heather Williams – MWH Assistant Project Manager Dave Thompson – MWH Lead Civil Engineer Paul Richards – MWH Senior Geotechnical Engineer Matt Prociv – MWH Civil Engineer Wade Moore – MWH Supervising Hydraulics Engineer Jeff Coleman – MWH Supervising Engineer Kirby Gilbert – MWH Regulatory Specialist Stetson Creek Diversion and Cooper Lake Dam Facilities Page ES-1 Feasibility Report – Final 14 March 2011 EXECUTIVE SUMMARY Chugach Electric Association, Inc. (Chugach) is assessing the feasibility of the proposed Stetson Creek Diversion and Cooper Lake Dam Facilities project (Project) as part of the requirements listed in FERC’s “Order on Offer of Settlement and Issuing New License” (Settlement Agreement) issued on August 24, 2007. The goal of the Project is to improve fish habitat in Cooper Creek by diverting cold water from Stetson Creek, a tributary of Cooper Creek, to Cooper Lake and releasing warmer surface water from Cooper Lake into Cooper Creek. Several options to meet the goal of providing warmer water to Cooper Creek were examined in the August 2004 “Potential Cooper Creek Protection, Mitigation and Enhancement Measures” (PME) Report developed by MWH for Chugach and one option became the basis of the Settlement Agreement requirements. Based on the results of that report, Chugach asked MWH to assess the feasibility of the selected option – a diversion dam and pipeline, and outlet works at Cooper Lake Dam. Feasibility of the Project was assessed based on the requirements in the Settlement Agreement, which were somewhat revised from the selection option in the PME Report. Under the terms of the Settlement Agreement, virtually all water in Stetson Creek may be diverted to Cooper Lake. No specified minimum flow was indicated in the Settlement Agreement to be maintained in Stetson Creek. Similarly, per the Settlement Agreement, a range of target flows must be released from the warmer portions of Cooper Lake (variable throughout the year) into Cooper Creek but are subject to change by an Interagency Committee, up to a maximum release of 30 cfs. Maximum annual volumes and maximum instantaneous design flows are specified in the Settlement Agreement for diversion and temperature releases. The Diversion Dam is planned to be located high on Stetson Creek to take advantage of more favorable geologic conditions and a safer and more constructible pipeline route. Following field investigations conducted in 2009, cost and construction considerations were developed for two options for the outlet works – a Gravity Option and a Siphon Option. The Gravity Option incurs significant cost, risk and construction difficulty because an open cut is required through the FERC-regulated Cooper Lake Dam. The Siphon Option attempts to reduce cost, risk, construction difficulty and dam safety issues by cutting through the rock spillway and installing a siphon pipeline system. Other alternatives were briefly examined to explore the potential for cost savings, though no formal cost estimates were performed for these options. Estimated total Project costs for the two Cooper Creek release options mentioned previously were developed in early 2010. The Siphon Option was estimated to have the lower total Project cost with an Association for the Advancement of Cost Engineering (AACE) International Class 4 cost range of $16.4 to $23.9 million in January 2010. This estimate has an accuracy of -15% to +25%, which is standard for feasibility level studies with project definition less than 15%. The 2010 cost estimates were based on a recommended, two-season, 2012-2013, construction schedule. The 2010 estimates were compared to those prepared in 2004 to study potential protection, mitigation and enhancement measures (MWH, 2004). The purpose of the 2004 studies, and subsequent updates, was to determine conceptual project layouts and cost estimates for the Stetson Creek Diversion and Cooper Lake Dam Facilities Page ES-2 Feasibility Report – Final 14 March 2011 purpose of comparison of the various alternatives. The 2004 study examined a range of alternatives, which included several alternatives that were similar to those studied herein, though none were precisely the same. The 2004 report estimates were later used as a basis for the $11.04 million (in 2004 dollars) target project cost. Chugach contracted MWH to conduct additional geotechnical investigations for the Siphon Option in 2010. Some design layout changes were made as a result. Updated layouts and geotechnical investigation results were prepared for the Siphon Option based on the 2010 field work and are included in this report. The Siphon Option cost estimate was updated to reflect the 2011 design changes and the latest available cost data. The 2011 Siphon Option project cost estimate indicates no net change from the earlier estimated range of $16.4 to 23.9 million (December 2010 dollars). A proposed project schedule that reflects a two-season, 2013-2014, construction period has also been prepared. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-1 Feasibility Report – Final 14 March 2011 1.0 INTRODUCTION 1.1 BACKGROUND As part of the requirements listed in the Federal Energy Regulatory Commission (FERC) “Order on Offer of Settlement and Issuing New License” (Settlement Agreement) issued on August 24, 2007, Chugach Electric Association, Inc. (Chugach) is assessing the feasibility of the proposed Stetson Creek Diversion and Cooper Lake Dam Facilities Project (Project). The Project would be located at the northern extent of the existing Cooper Lake Project, approximately 4.5 miles south of Cooper Landing, Alaska. The overall purpose of the Project is to divert flow from Stetson Creek to Cooper Lake, and release warmer surface water from Cooper Lake to Cooper Creek. 1.2 EXISTING PROJECT LAYOUT The existing Cooper Lake Project consists of: A 920-foot-long, rock-and-fill dam that raises the elevation of Cooper Lake (a natural lake) to a licensed maximum operating level of 1,210 feet mean sea level. Cooper Lake, with a surface area of 2,910 acres. An intake structure on the southeast shore of Cooper Lake; a 10,686-foot-long tunnel and penstock. A powerhouse located on the southwest shore of Kenai Lake containing two turbine- generators, each rated at 9.69 MW. A 6.3-mile-long, 69-kilovolt (kV) transmission line extending from the powerhouse to the Quartz Creek substation. A step-up transformer at the Quartz Creek substation. A 90.4-mile-long, 115-kV transmission line from the Quartz Creek substation to the Anchorage substation. Operations currently divert all flow from Cooper Lake through the tunnel/penstock to the powerhouse, where it is discharged into Kenai Lake. The 4.8-mile-long Cooper Creek bypassed reach below the Cooper Lake dam receives no flow from Cooper Lake; there is no existing minimum flow requirement for Cooper Creek and no outlet structure to provide such flows. The project has an average annual generation of about 48,500 megawatt-hours (MWh) and an average outflow through the powerhouse of about 100 cubic feet per second (cfs), which is equivalent to 73,000 acre-feet/year. Powerhouse discharge ranges from 0 to 380 cfs into Kenai Lake, which is the source of the Kenai River. 1.3 PROPOSED MODIFICATIONS The modifications under consideration would be accomplished by constructing a new Diversion Dam on Stetson Creek. Water impounded by this dam would be diverted to Cooper Lake through a 2.2 mile long pipeline. Outlet facilities would be installed at Cooper Lake Dam to allow controlled amounts of water to be released into Cooper Creek to enhance salmon spawning habitat. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-2 Feasibility Report – Final 14 March 2011 1.4 OTHER DESIGN ALTERNATIVES MWH conceptualized many design alternatives in 2004 in order to help determine a preferred option for the Project. The systems proposed in this Feasibility Report are based on design requirements contained in the 2007 Settlement Agreement. The current design requirements in the Settlement Agreement differ in some respects from any of the previously considered alternatives. MWH has briefly evaluated some additional cost-saving measures, design alternatives and potential design requirement changes that may reduce overall project costs as described below, but do not meet the terms of the Settlement Agreement. 1.4.1 Reducing Maximum Diverted Flow from 110 cfs to 70 cfs This option would involve reducing the size of the Diversion Structure and the Diversion Pipeline diameter which would effectively reduce the diversion capacity from the Settlement Agreement stipulated 110 cfs to 70 cfs. The inside diameter of the HDPE pipe would be reduced from 36 inches to 32 inches. It is estimated that this option would result in an overall cost savings of from $1.4 to $2.0 million over the estimates provided in Section 6.0. All other features of the project would remain unchanged, including the Settlement Agreement-required monthly releases to Cooper Creek from Cooper Lake totaling 10,256 cfs. Associated with this option the total volume of water diverted from Stetson Creek to Cooper Lake that can be used for power generation would be reduced. If 70 cfs were the maximum diverted through the Diversion Pipeline then the annual reduction in water volume would be about 960 acre-feet (ac-ft), leaving about 7,070 ac-ft annually for power production. 1.4.2 Hydroelectric / Pumped Flow Option This option involves installing a small hydroelectric turbine/generator unit on the Stetson Diversion Pipeline to generate power sufficient on an annual basis to power the pumping of required flow releases to Cooper Creek from Cooper Lake. It was assumed that a transmission line (approximately 4.5 miles) would need to be constructed along the existing main dam access road to supply power for pumping during periods of generation deficit and take excess generation during surplus periods. Flow available for diversion was based on about 5 years of recorded flows on Stetson Creek downstream from the proposed Diversion Dam, as shown on Table 1-1. Flows at the Diversion Dam would be about 90% of the flows at the USGS gaging station. Table 1-1 Recorded Streamflow (ac-ft) on Stetson Creek at USGS Gage 15260500 Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total 1958 ----- ----- ----- ----- 3,051 5,391 3,247 2,321 1,607 1,176 676 466 ----- 1959 369 303 329 405 1,894 5,008 2,664 1,989 1,644 996 750 536 16,887 1960 430 310 266 286 2,878 3,884 3,039 2,557 2,281 1,289 746 950 18,915 1961 1,137 524 337 381 2,803 5,855 4,310 2,858 3,600 2,069 581 494 24,948 1962 430 278 307 351 1,168 4,431 2,900 1,317 1,162 930 978 486 14,739 1963 361 278 274 307 1,805 3,041 3,368 1,527 904 -------------------- Average 545 339 303 346 2,267 4,602 3,255 2,095 1,866 1,292 746 586 18,241 Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-3 Feasibility Report – Final 14 March 2011 The Settlement Agreement indicates that the Stetson Creek diversion can take up to 18,255 ac-ft per year. Considering the average flow at the Stetson Creek Diversion Dam would be approximately that, it was assumed that the minimum instream flow releases at Stetson Creek Diversion Dam would be zero for this study. The flow pumped from Cooper Lake over the dam and released into the downstream spillway channel was assumed to vary from 10 cfs to 25 cfs on a monthly basis according to the initial flow requirements in the Settlement Agreement. The minimum instream flow releases used in this analysis are shown in Table 1-2. Table 1-2 Minimum Instream Flows (cfs) The Stetson Creek Diversion Dam normal pool level would be at EL 1,437 and the micro-hydro tailwater was assumed to be at EL 1,220. The pipeline from the Diversion Dam to Cooper Lake would be about 11,000 feet long and would have a diameter that varies with the maximum flow rate, as shown in Table 1-3. For each pipeline maximum flow rate shown in Table 1-3, the smaller diameter would be selected when considering water supply needs only, and the larger diameter would be selected with consideration given to hydroelectric generation. Table 1-3 also shows the average total diversion flow in the pipeline based on about 5 years of flow data on Stetson Creek and assumed minimum releases at the Diversion Dam. Table 1-3 Stetson Creek Diversion Dam to Cooper Lake Pipeline The pumped pipeline over the spillway was assumed to be 30-inches in diameter. The pumped pipeline would have a high point at about EL 1,221 so that it could go over the dam crest. Based on the required flows shown in Table 1-2, the pumping energy required would be about 520 MWh per year. Computer power analyses were performed and assumed that Cooper Creek flow releases and the Cooper Lake elevations were the same in all runs, therefore, pumping energy was also the same in all runs. Power study model runs were performed on a daily time increment using the slightly more than five years of recorded daily flows in Stetson Creek, as adjusted to the Diversion Dam site. Cooper Lake elevation data is necessary to determine the pumping energy required. Because there is no coincident Stetson Creek flow and Cooper Lake elevation data, a historic year of Cooper Lake elevation data was selected from the period 1985 through 2003 and assigned to a Location Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Stetson Creek Releases (cfs) 0 0 0 0 0 0 0 0 0 0 0 0 Cooper Creek Releases (cfs) 10 10 10 10 10 20 25 20 20 15 10 10 Pipeline Maximum Flow (cfs) 40 70 110 Pipe diameter (ft) 2.0 2.5 2.5 3.0 3.0 3.5 Pipe area (sq.ft.) 3.1 4.9 4.9 7.1 7.1 9.6 Maximum velocity (ft/sec) 12.7 8.1 14.3 9.9 15.6 11.4 Static head (feet) 217 217 217 217 217 217 Head losses at max. flow (feet) 180 59 181 73 179 83 Average Pipeline Flow (cfs) 17.6 17.6 21.0 21.0 22.0 22.0 Average Annual Pipeline Flow (ac-ft) 12,742 12,742 15,203 15,203 15,927 15,927 Parameter Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-4 Feasibility Report – Final 14 March 2011 corresponding year of Stetson Creek flow data, based on the fact that higher flow years correspond to higher lake level years. Using estimated generation from the daily flow diversions in the Stetson Diversion Pipeline minus pumping energy requirements, the net surplus (or deficit) of energy was determined as shown in Table 1-4 for three different maximum pipeline flow rates and a range of maximum powerhouse flows for each pipeline flows. Powerhouse generation was limited by the turbine capability for the maximum and minimum flow range and the maximum and minimum head range. For cases where the powerhouse maximum flow is less than the pipeline maximum flow, a bypass system at the powerhouse would be necessary to direct excess flow to Cooper Lake. Maximum powerhouse output occurs at much less than the maximum pipeline flow rate due to high pipeline head losses at the higher flow rates. Powerhouses with higher maximum flows can actually have lower average annual generation than a powerhouse with lower flows because the operating range for the larger powerhouses is limited to the lower head range of higher flows. The net generation shown in Table 1-4 is powerhouse generation minus the pumping energy requirement (520 MWh/year) on an average annual basis. Table 1-4 Powerhouse Results – Generation All Year Due to icing conditions, it may be difficult to reliably operate the diversion and powerhouse during the December through April period. As shown in Table 1-5, shutting down the hydroelectric during this period would not cause a significant loss of generation. Tables 1-6, 1-7, and 1-8 present the monthly generation surplus (or deficit) by month for a reasonable choice of powerhouse size corresponding to the three different maximum pipeline flows. Tables 1-9 and 1-10 show results similar to Tables 1-4 and 1-5, respectively, except with pipe diameters increased by 6 inches in each case to provide increased hydroelectric generation (i.e., less head loss). The resulting generation increases are the greatest where the reductions in maximum head losses are the largest. For example, if a 30-inch pipe were used with a 40 cfs maximum pipeline flow, instead of a 24-inch pipe (Table 1-4), the annual average generation would be about 4 times greater (1,229 MWh versus 310 MWh). Pipeline Maximum Flow and Diameter Powerhouse 40 cfs - 2-ft diameter 70 cfs - 2.5-ft diameter 110 cfs - 3-ft diameter Maximum Avg. PH PH Max. Net Avg. PH PH Max. Net Avg. PH PH Max. Net Flow Flow Output Generation Flow Output Generation Flow Output Generation (cfs) (cfs) (kW) (MWh/year) (cfs) (kW) (MWh/year) (cfs) (kW) (MWh/year) 90 ----- ----- ----- ----- ----- ----- 16.9 727 1,194 80 ----- ----- ----- ----- ----- ----- 17.5 727 1,274 70 ----- ----- ----- 13.2 461 686 17.6 727 1,313 60 ----- ----- ----- 13.6 461 751 17.6 707 1,340 50 ----- ----- ----- 13.9 461 824 17.2 647 1,347 40 7.5 264 192 13.3 455 808 15.9 556 1,247 30 7.9 264 271 12.3 397 778 14.3 440 1,120 20 7.7 247 310 10.6 291 668 11.9 304 903 15 7.0 207 280 9.2 225 554 10.2 231 733 10 5.7 148 152 7.1 153 338 7.8 155 458 Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-5 Feasibility Report – Final 14 March 2011 Table 1-5 Powerhouse Results – No Generation December - April Table 1-6 Powerhouse/Pumping Net Generation (MWh) 110 cfs Maximum Pipeline Flow and 50 cfs Maximum Powerhouse Flow Table 1-7 Powerhouse/Pumping Net Generation (MWh) 70 cfs Maximum Pipeline Flow and 40 cfs Maximum Powerhouse Flow Table 1-8 Powerhouse/Pumping Net Generation (MWh) 40 cfs Maximum Pipeline Flow and 20 cfs Maximum Powerhouse Flow Pipeline Maximum Flow and Diameter Powerhouse 40 cfs - 2-ft diameter 70 cfs - 2.5-ft diameter 110 cfs - 3-ft diameter Maximum Net Compared Net Compared Net Compared Flow Generation to All Year Generation to All Year Generation to All Year (cfs) (MWh/year) Generation (MWh/year) Generation (MWh/year) Generation 90 ----- ----- ----- ----- 1,173 98.2% 80 ----- ----- ----- ----- 1,253 98.3% 70 ----- ----- 666 97.0% 1,291 98.3% 60 ----- ----- 714 95.1% 1,302 97.2% 50 ----- ----- 763 92.6% 1,284 95.4% 40 132 68.7% 743 92.0% 1,181 94.7% 30 150 55.5% 652 83.8% 992 88.6% 20 81 26.1% 432 64.7% 666 73.7% 15 1 0.2% 269 48.4% 445 60.7% 10 (128)----- 52 15.4% 170 37.2% Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total 1958 ----- ----- ----- ----- ----- 208.8 349.4 299.8 207.1 157.2 30.1 (24.4)1228.0 1959 (32.6) (32.4) (38.1) (37.4)242.8 222.3 327.1 257.2 212.9 129.9 48.2 (25.2)1274.7 1960 (27.6) (26.7) (31.6) (32.1)173.8 347.9 372.3 332.5 295.2 176.2 62.7 120.0 1762.5 1961 148.6 (19.2) (21.7) (23.1)266.7 152.3 331.0 334.5 289.4 201.3 (10.0) (22.5)1627.4 1962 (32.3) (29.8) (33.5) (33.0)131.2 204.8 277.6 149.2 127.8 112.2 98.1 (26.0)946.3 1963 (34.8)(32.7)(38.9)(39.3)181.1 334.0 294.8 176.4 86.8 ---------------927.4 Average 4.3 (28.2) (32.8) (33.0)199.1 245.0 325.4 258.3 203.2 155.3 45.8 4.4 1346.9 Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total 1958 ----- ----- ----- ----- -----(32.6)158.6 245.1 190.5 148.7 76.0 (18.5)767.7 1959 (32.6) (32.4) (38.1) (37.4)186.2 (26.8)223.4 225.7 193.4 125.7 69.6 (12.7)844.0 1960 (27.6) (26.7) (31.6) (32.1)114.0 53.9 209.0 258.6 230.9 167.8 71.0 117.6 1104.7 1961 143.9 (19.2) (21.7) (23.1)141.7 (29.2) (17.9)231.5 153.1 142.0 36.3 (22.5)715.1 1962 (32.3) (29.8) (33.5) (33.0)128.6 66.5 130.8 140.5 118.1 109.1 102.3 (26.0)641.3 1963 (34.8)(32.7)(38.9)(39.3)143.3 165.3 97.2 163.1 83.8 ---------------507.0 Average 3.3 (28.2) (32.8) (33.0)142.8 32.8 133.5 210.7 161.6 138.7 71.0 7.6 808.2 Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total 1958 ----- ----- ----- ----- -----(67.0) (79.4)31.4 102.7 107.1 80.8 45.0 220.6 1959 22.9 (11.7) (20.6)16.6 90.1 (71.0) (60.3)65.9 96.0 111.0 88.6 54.1 381.6 1960 36.8 0.4 (28.4) (20.3)67.3 (68.5) (84.5) (4.8)25.3 132.5 89.3 109.6 254.6 1961 128.0 49.8 2.2 27.8 33.3 (57.8) (75.2) (5.0) (3.1)74.5 68.1 51.0 293.6 1962 32.1 (29.8) (33.5)8.7 78.7 (49.1) (33.7)105.4 75.8 98.7 92.6 46.4 392.3 1963 19.5 (32.7)(38.9)(31.3)28.4 (60.9)(68.9)97.1 73.4 ---------------(14.5) Average 47.8 (4.8) (23.8)0.3 59.5 (62.4) (67.0)48.3 61.7 104.7 83.9 61.2 309.5 Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-6 Feasibility Report – Final 14 March 2011 Table 1-9 Powerhouse Results – Increased Pipe Diameter – Generation All Year Table 1-10 Powerhouse Results Increased Pipe Diameter – No Generation December - April Tables 1-9 and 1-10, in comparison with Tables 1-4 and 1-5, indicate an incremental increase in energy production with an incremental increase in Diversion Pipeline diameter due to the reduction in pipe friction head losses. It is estimated that to increase the pipeline diameter by 6 inches may increase the cost to the project by $1.0 to $1.5 million. No attempt has been made to estimate the cost to install a micro-hydro generator, pump system and associated transmission line or to determine the benefits of the surplus power. To do so would require making a preliminary layout and communicating with generating and pump equipment suppliers. It should be noted that a small hydro and pumped flow installation would Pipeline Maximum Flow and Diameter Powerhouse 40 cfs - 2.5-ft diameter 70 cfs - 3.0-ft diameter 110 cfs - 3.5-ft diameter Maximum Avg. PH PH Max. Net Avg. PH PH Max. Net Avg. PH PH Max. Net Flow Flow Output Generation Flow Output Generation Flow Output Generation (cfs) (cfs) (kW) (MWh/year) (cfs) (kW) (MWh/year) (cfs) (kW) (MWh/year) 110 ----- ----- ----- ----- ----- ----- 16.3 1068 1,469 100 ----- ----- ----- ----- ----- ----- 18.5 1068 1,515 90 ----- ----- ----- ----- ----- ----- 18.9 1046 1,570 80 ----- ----- ----- ----- ----- ----- 19.2 996 1,630 70 ----- ----- ----- 19.1 727 1,468 19.1 924 1,645 60 ----- ----- ----- 18.8 707 1,473 18.8 830 1,641 50 ----- ----- ----- 18.3 647 1,458 18.3 719 1,610 40 16.8 455 1,229 16.8 556 1,336 16.8 593 1,465 30 14.9 397 1,093 14.9 440 1,186 14.9 455 1,287 20 12.3 291 880 12.3 304 948 12.3 308 1,018 15 10.5 225 713 10.5 231 766 10.5 233 819 10 8.0 153 444 8.0 155 480 8.0 156 516 Pipeline Maximum Flow and Diameter Powerhouse 40 cfs - 2.5-ft diameter 70 cfs - 3.0-ft diameter 110 cfs - 3.5-ft diameter Maximum Net Compared Net Compared Net Compared Flow Generation to All Year Generation to All Year Generation to All Year (cfs) (MWh/year) Generation (MWh/year) Generation (MWh/year) Generation 110 ----- ----- ----- ----- 1,469 100.0% 100 ----- ----- ----- ----- 1,515 100.0% 90 ----- ----- ----- ----- 1,548 98.6% 80 ----- ----- ----- ----- 1,608 98.7% 70 ----- ----- 1,446 98.5% 1,623 98.7% 60 ----- ----- 1,435 97.4% 1,603 97.7% 50 ----- ----- 1,395 95.7% 1,547 96.1% 40 1,164 94.7% 1,270 95.0% 1,398 95.4% 30 967 88.4% 1,058 89.2% 1,159 90.0% 20 644 73.2% 719 75.9% 779 76.6% 15 427 59.9% 478 62.4% 531 64.8% 10 158 35.6% 192 40.1% 227 44.1% Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-7 Feasibility Report – Final 14 March 2011 require continual and regular mechanical maintenance, including during the winter when the site is inaccessible making this option seasonally problematic. 1.4.3 Pumped Flow Option This option would involve installing pump(s) to pump the entire required Cooper Creek release from Cooper Lake over the Cooper Lake Dam; up to 30 cfs. This option would require that a distribution line be installed along the main dam access road (approximately 4.5 miles) and installing pumps in a pump house adjacent to Cooper Lake Dam. Adders to project costs would be the distribution line, pumps and associated facilities. Comparing this option to the Siphon Option of paragraph 3.5.2.2 in this Feasibility Report, the main savings would be associated with extensive rock excavations in the spillway and long pipeline. No attempt has been made to estimate this option. The comparison would be the net present worth to supply 520 MWh of electrical energy annually to pump the entire flow volume versus the potential net savings, if any, to install a pump facility in lieu of siphon facilities. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-1 Feasibility Report – Final 14 March 2011 2.0 FIELD INVESTIGATIONS Field investigations were conducted in fall 2009 to assess the major components of the proposed site improvements. Geotechnical investigations were performed for the major Project facilities including the Diversion Dam, the Diversion Pipeline, and outlet facilities. Site investigations included development of a field investigation plan, a geological reconnaissance, geophysical surveys, test pit explorations, laboratory testing, and an avalanche risk assessment. Summaries of the 2009 field investigations with respect to proposed Project features are summarized in Sections 2.1 and 2.2. Detailed reports of the 2009 geotechnical investigations and avalanche risk survey are presented in Appendices A and C, respectively. In addition to the field investigations, a bathometric survey was conducted near the upstream toe of Cooper Lake Dam and along the alignment of the Diversion Pipeline outfall. A summary of the bathometric survey is presented in Appendix D. Additional field investigations were conducted in 2010 for the Siphon Option (see paragraph 3.5.2.2). Summaries of 2010 field investigations are provided in Section 2.3. A detailed report of all geotechnical work conducted for the project is included in Appendix F. 2.1 DIVERSION STRUCTURE A geologic reconnaissance and an avalanche risk assessment were conducted in 2009 to evaluate the conceptual location of a diversion dam. Site conditions such as exposed bedrock rock, abutment slopes, geologic hazards, and site access were qualitatively considered as part of the geologic reconnaissance. As a result of our initial findings, four alternate diversion dam locations (Alternates 1 through 4) were identified and considered. These four potential diversion dam locations were assessed to determine the susceptibility to avalanches. 2.1.1 Diversion Pipeline and Pipeline The Diversion Pipeline was investigated during a geological reconnaissance and by conducting a series of geophysical seismic refraction surveys in 2009. The alignment of the pipeline was modified from that envisioned at the onset of the 2009 field explorations. This modification was made to account for the currently proposed location of the Diversion Dam, to minimize portions of the alignment that traverse potentially unstable slopes, and to improve the hydraulics of the pipeline. Since the modified alignment was selected following the completion of the 2009 field investigations, evaluations of the new alignment were limited to a review of existing topographic data. 2.1.2 Cooper Lake Dam 2009 field investigations of Cooper Lake Dam were conducted to evaluate two potential Cooper Lake outlet facilities options. These facilities included a Gravity Outlet Facility Option (Gravity Option) and a Spillway Siphon Outlet Facility Option (Siphon Option). The Gravity Option includes a 36-inch diameter conduit that would extend from Cooper Lake through the existing near dam Station 9+00 to Cooper Creek. Site investigations of the Gravity Option included six test pit explorations along the proposed alignment. The purpose of these Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-2 Feasibility Report – Final 14 March 2011 explorations was to characterize the physical and strength properties of the subsurface soil at selected locations to aid in the analysis and design of this option. The Siphon Option would consist of a 30-inch diameter conduit that would extend from Cooper Lake through the spillway, and would discharge into Cooper Creek nearly 600 feet downstream of the spillway outfall. 2009 site investigation of the Siphon Option included a geophysical seismic refraction survey of the exposed bedrock. The purpose of this survey was to evaluate potential rock excavation methods required for construction. 2.1.3 Cooper Lake Dam Drilling Two borings were planned as part of the 2009 geotechnical feasibility investigation plan. The borings were removed from the investigation plan following a meeting with FERC on September 2, 2009. These borings could be conducted at a later date during more advanced design evaluations of the Gravity Option, if necessary. 2.1.4 Borrow Areas Two potential borrow sources were explored as part of the 2009 site investigations; the Right Abutment Borrow source and the Outfall Borrow sources. The Right Abutment Borrow source is located upstream of Cooper Lake Dam’s right abutment. It is presumed that this borrow source was used for fill material during the construction of the dam. The Right Abutment Borrow source was explored by excavating four test pits and conducting one geophysical seismic refraction survey. The Outfall Borrow source is located along the shoreline of Cooper Lake near the outfall of the proposed Diversion Pipeline. This borrow source could potentially extend from the upstream edge of the existing spillway to any alluvial fan located approximately 2,000 feet south of the left abutment of Cooper Lake Dam. Site investigations of the Outfall Borrow source included excavating two test pits. 2.2 ANALYSIS OF 2009 FIELD INVESTIGATIONS 2.2.1 Diversion Dam A qualitative evaluation of the proposed diversion dam location and four alternate locations was conducted. Ultimately, the Diversion Dam site Alternate 2, situated at an elevation of 1,424 feet, was selected as the most feasible option – given the current understanding of site conditions, the resulting pipeline alignment, the perceived construction accessibility, the existing topographic data, and the resulting hydraulic head. While this location is susceptible to avalanche hazards with a return period on the order of 10 to 50 years, it is felt that the risk of avalanches to the Diversion Dam is significantly offset by the ability to avoid potentially unstable slopes along the Diversion Pipeline. Given the proposed construction methods, avalanches are expected to have a minimal impact on the Diversion Dam structure. Further, avalanche impacts on associated Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-3 Feasibility Report – Final 14 March 2011 facilities, such as sluice gates and pipelines, can be mitigated through careful design and by including protective measures. 2.2.2 Diversion Pipeline Preliminary evaluations and analysis of the Diversion Pipeline consisted of a visual assessment and seismic refraction surveys. The visual assessment of the alignment was conducted as part of the geological site reconnaissance. Portions of the alignment between the site of the Diversion Dam and the ridgeline that divides Stetson and Cooper Creeks were not accessible due to prohibitively steep slopes limiting visual assessment at these locations. Selected locations between the dividing ridgeline and the Diversion Pipeline outfall at Cooper Lake were investigated by seismic refraction surveys. Seismic refraction surveys were used to assess the depth of overburden and the rippability of the underlying bedrock. 2.2.2.1 Visual Site Assessment Potential geologic hazards were identified at various locations along the Diversion Dam alignment. Steep slopes showing signs indicative of localized and shallow slope failures were observed at several locations along the alignment. While the Diversion Pipeline along Stetson Creek was not observed in its entirety, it is expected that shallow slope failures along Stetson Creek are common. This expectation is substantiated by topographic data indicating the presence of hummocky topography. An active rock glacier was observed upslope of the proposed Diversion Pipeline outfall. This rock glacier is a slowly moving mass of rock that is susceptible to mass wasting events such as sloughing of the toe, debris flows, and rock avalanches. Over geologic time, this rock glacier will likely produce debris flows and rock avalanches that will run out through the drainage that feeds the alluvial fan where the Diversion Pipeline outfall is located. While it is considered a very low risk to the Diversion Pipeline outfall, there is a slight risk for mass wasting events near the outfall of the Diversion Pipeline following very high precipitation events or during large earthquakes. If these events were to occur, it is most probable that the debris from the rock avalanche would come to rest approximately 500 feet southeast of the pipeline outfall. 2.2.2.2 Rock Excavation Analysis A preliminary analysis of potential rock excavation methods along the Diversion Pipeline was conducted. The analysis was based on rock velocities obtained from the seismic refraction surveys conducted along the alignment. Based on the seismic refraction surveys, bedrock is commonly located within 10 feet or less below the existing ground surface along the alignment. Generally, trench excavation depths should be in the range of 6 to 8 feet. Seismic refraction velocities indicate that this bedrock is not rippable. Accordingly, it is expected that drilling and controlled blasting techniques will be required to excavate trenches and benches at several locations along the proposed Diversion Pipeline alignment. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-4 Feasibility Report – Final 14 March 2011 2.2.3 Cooper Lake Dam Two conceptual outlet facility options were analyzed as part of the preliminary geotechnical study. The Gravity Option consists of a gravity fed outlet facility that would extend from Cooper Lake through the existing dam to a discharge point downstream of the dam. The gravity option would require that a large excavation be made through the existing dam in order to place the outlet pipeline and construct a gate structure. Analyses of the conceptual Gravity Option include a preliminary evaluation of excavation slope stability and a preliminary granular filter analysis. The Siphon Option would consist of a siphon outlet facility extending from Cooper Lake through the existing spillway to a discharge point downstream. Siphon systems have a limited amount of elevation that can be cleared without the occurrence of cavitation that vary based on site elevation, flow efficiency, and system design. Seismic refraction surveys were used to help preliminarily determine the appropriate rock excavation methods that will be required for the construction of the siphon option. The analyses performed with respect to these two options are summarized in the following paragraphs. 2.2.3.1 Preliminary Slope Stability Analysis A preliminary slope stability analysis was conducted on the anticipated construction cut slopes of the Gravity Option. A subsurface soil model was developed based on as-built drawings, test pit explorations, and field observations. Preliminary soil characteristics were based on laboratory testing and published soil strength relationships. Construction cut slopes within the existing dam were limited to 3 horizontal to 1 vertical (3H:1V) based on preliminary discussion with FERC. A sensitivity analysis of the model was conducted with respect to the strength of the fine grained core material to determine the minimum required strength need to maintain the stability of this slope. Results of the slope stability analysis indicate the excavation side slope would have a factor of safety of 1.7 based on preliminary soil properties. Sensitivity analyses indicate that a 3H:1V slope would maintain an acceptable safety factor provided the core material strength is approximately 750 pounds per square feet (psf) or greater. 2.2.3.2 Preliminary Granular Filter Analysis Granular filters are used within zoned earth and rockfill dams, such as Cooper Lake Dam, to prevent fines from migrating from one zone of the dam into the pore space of an adjacent zone. A graded granular filter would be required as part of the reconstruction of the dam for the Gravity Option. A preliminary granular filter analysis was conducted to evaluate the availability of potential granular filter sources. Based on this preliminary design, the onsite borrow sources evaluated as part of this investigation would not meet the filter criteria without processing; however, Cover Coat Material Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-5 Feasibility Report – Final 14 March 2011 Type 2 as specified by Table 703-4 of the Alaska Department of Transportation and Public Facilities (ADOT&PF) standard specifications meets the filter requirements. Accordingly, filter materials could likely be obtained from local borrow sources or by screening on-site borrow sources. 2.2.3.3 Spillway Excavation Analysis The envisioned Siphon Option would require a rock cut of up to 33 feet to meet required grades. A spillway excavation analysis was conducted to determine whether or not bedrock at this location could be ripped by conventional methods. This rippability analysis was based on rock velocities obtained from one geophysical seismic refraction survey. Based on the geophysical survey, the bedrock has a seismic velocity of 15,000 feet per second (fps). This seismic velocity indicates that this bedrock would not be rippable. Accordingly, drilling and controlled blasting techniques would be required to construct the Siphon Option. 2.2.4 Borrow Areas Two potential borrow sources were identified and explored as part of the 2009 Geotechnical Feasibility Study. Selected samples were collected from a series of test pit excavations, conducted at these locations. A series of laboratory tests were conducted to evaluate the physical properties of the borrow materials. Available topographic data was used, in concert with observations made during the test pit excavations, to conduct a preliminary volume assessment of available borrow material at the two borrow sites. In addition, analytical testing was conducted on selected borrow soil samples to evaluate their corrosive properties. These analyses are summarized in the following paragraphs. 2.2.4.1 Borrow Material Properties and Volume Based on observations and laboratory testing, the two potential borrow sources investigated consist of poorly-graded sand and poorly-graded to well-graded gravels, with varying amounts of cobbles and boulders. This material is suitable for use in applications such as shell material, trench backfill, and road surfacing. The borrow source soils may be suitable for other fill applications such as pipe bedding, granular filter, and concrete aggregate if processed. Volume calculations of both the Right Abutment Borrow source and the Outfall Borrow source have been conducted based on available topographic data assuming a base excavation elevation of 1,182 feet. This elevation was selected based on the observed groundwater elevation at the time of the test pit excavations. Additional borrow material may be realized if dewatering techniques are implemented or if the reservoir elevation is lowered. Calculations indicate the in- place volume of potential borrow material within the Right Abutment Borrow source is as much as 70,000 cubic yards. As much as an additional 9,500 cubic yards could be mined from the Outfall Borrow source. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-6 Feasibility Report – Final 14 March 2011 2.2.4.2 Corrosion Testing Corrosion testing was conducted on selected soil samples from the potential borrow sources. Samples were tested for parameters including pH, specific conductivity (inverse of resistivity), chloride, sulfate, sulfide, oxidation/reduction potential, and corrosivity. The results of the corrosion testing indicate the potential borrow materials have a low potential for corrosion based on each parameter analyzed. Accordingly, the borrow sources explored are suitable for concrete aggregate and pipe backfill with respect to corrosion potential. 2.3 2010 ADDITIONAL FIELD INVESTIGATIONS Based on the findings of the above 2009 feasibility investigation and analysis, further detailed field investigations for the Siphon Option were conducted during the summer of 2010 and are summarized below. 2010 site investigations included development of a field investigation plan, additional geological reconnaissance, drilling explorations at the diversion dam site and the siphon alignment, and additional laboratory testing. A detailed report documenting all geotechnical investigations conducted by MWH for this project is included as Appendix F of this report. 2.3.1 Diversion Dam 1. Conducted two rock core explorations, one on each abutment, to characterize the foundation conditions at the Diversion Dam site. Down-hole tele-viewer logs of the explorations were attempted. 2. Conducted packer testing within the suggested explorations to determine the groutability and need for a cut-off or consolidation grouting curtain below the foundation of the envisioned Diversion Dam. 3. Conducted two geophysical seismic refraction surveys, one on each abutment, of the proposed diversion dam alignment. 4. Obtained topographic data for slopes above the Diversion Dam and the associated reservoir area to aid in the evaluation and design of the structure. 5. Conducted a geologic reconnaissance of the slopes near the conceptual reservoir to identify areas that may be destabilized by increased water elevations within Stetson Creek. 2.3.2 Diversion Pipeline Alignment 1. Conducted geologic reconnaissance of the conceptualized alternate alignment based on the selected location of the diversion dam based on the results and findings of the 2009 site evaluations. The new diversion pipeline alignment also improves the pipeline’s hydraulic characteristics and reduces exposure to steep slopes within the Stetson Creek Drainage. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-7 Feasibility Report – Final 14 March 2011 2. Evaluated the potential impact and mitigation measures, if required, of areas of shallow slope instability and irregular topographic features identified during this study and the recommended geologic reconnaissance mentioned above. 2.3.3 Siphon Outlet Facilities 1. Conducted additional subsurface explorations of the Siphon Option: a. Conducted two rock core borings within the spillway to further characterize subsurface rock conditions, assess rock slope stability following the proposed excavation, evaluate the need for shoring and consolidation grouting, and provide data for use by the drilling and blasting subcontractor. Attempted down-hole tele- viewer logging of the explorations to optimize the information obtained from these explorations. b. Conducted two borings to identify subsurface material within alignments of the Siphon Option. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-1 Feasibility Report – Final 14 March 2011 3.0 PROJECT FEASIBILITY 3.1 DESIGN CRITERIA AND ASSUMPTIONS The design criteria for the Stetson Creek Diversion and Cooper Lake Dam Facilities are based on Chugach’s Settlement Agreement filed August 24, 2007, with FERC for the Cooper Lake Hydroelectric Project No. 2170. Items not specifically identified in the Settlement Agreement are defined as assumptions. The assumptions are based on conversations with Chugach personnel and engineering judgment, as informed by available hydraulic, hydrologic, geotechnical, operations, and other data. 3.1.1 Design Criteria and Project Facts Cooper Lake Dam: Top of Dam EL – 1,220 feet Top of Dam Core EL – 1,215 feet Spillway Crest EL – 1,210 feet Dam Length – 920 feet Spillway Length – 800 feet Cooper Lake Water Surface Elevations (WSEL): Normal Cooper Lake operating range – 1,194 to 1,160 feet Average Yearly Cooper Lake WSEL fluctuation – 15 feet Average Monthly Cooper Lake WSEL fluctuation – 1 to 2 feet Average Daily Cooper Lake WSEL fluctuation – 1 inch Maximum Cooper Lake operating WSEL – 1,210 feet Minimum Cooper Lake operating WSEL – 1,160 feet Cooper Lake Storage Volumes: Cooper Lake Storage at WSEL 1,210 feet (crest of the spillway) – 230,000 ac-ft Cooper Lake Storage at WSEL 1,194 feet (FERC-restricted) – 190,000 ac-ft Cooper Lake Volume Available for Generation at WSEL 1,210 feet – 120,000 ac-ft Cooper Lake Volume Available for Generation at WSEL 1,194 feet – 80,000 ac-ft Cooper Lake Refill and Drawdown: Normal Cooper Lake Refill Period – May 1 to Sept 30 Normal Cooper Lake Drawdown Period – Oct 1 to Apr 30 Stetson Creek Diversion: Maximum Allowable Diversion from Stetson Creek – 110 cfs Minimum Volume Diverted from Stetson Creek to Cooper Lake per year – 18,285 ac-ft Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-2 Feasibility Report – Final 14 March 2011 Minimum Instream Flow (MIF) Remaining in Stetson Creek during Diversion – None specified, but to be taken “(if any) from the total amount of water available for release to Cooper Creek” as indicated in the Settlement Agreement. MIF in Stetson Creek will be set by Interagency Committee every year by May 31 after construction is complete. Maximum Number of Days of Flushing Flow through Stetson Creek Diversion in a Rolling 10-year period – 30 days Stetson Creek Diversion Flow Control – Manual Flushing Flow allowed when natural flow at the Mouth of Cooper Creek – 150 cfs Flushing Flow is provided only from Stetson Creek Diversion Expected Generation Increase from Stetson Creek Diversion Flow – 8,029 ac-ft Flows through the Stetson Creek Diversion Pipeline shall be monitored by Chugach on, at least, 15-minute intervals. The data collected shall be reported quarterly to the Interagency Committee. Cooper Lake Dam Facilities – Temperature Release: Total Volume Released from Cooper Lake into Cooper Creek per year – 10,256 ac-ft Maximum Instantaneous Cooper Lake Release Flow – 30 cfs (assumed to correspond to summer months requiring a release of 20 to 25 cfs, as indicated below, and higher lake levels) Flow release from Cooper Lake to Cooper Creek shall be monitored by Chugach on, at least, 15 minute intervals. The data collected shall be reported quarterly to the Interagency Committee. Cooper Lake Release to Cooper Creek: January – 10 cfs February – 10 cfs March – 10 cfs April – 10 cfs May – 10 cfs June – 20 cfs July – 25 cfs August – 20 cfs September – 20 cfs October – 15 cfs November– 10 cfs December – 10 cfs Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-3 Feasibility Report – Final 14 March 2011 3.1.2 Assumptions Assumptions include: Maximum Depth of Ice Cover – 4 feet Pre-Diversion Cooper Lake Inflow, 95 percent Exceedence Flow – 6.5 cfs Pre-Diversion Cooper Lake Inflow, 5% Exceedence Flow – 235 cfs Dam Facilities Inaccessible due to Snow – October 1 to April 30 Flow release from Cooper Lake to Cooper Creek may be required in addition to the 150 cfs requirement at the mouth of Cooper Creek for the Flushing Flow criteria. Flushing Flow is not a defined value and will be set by the Interagency Committee; therefore, it may be possible for some water to be diverted from Stetson Creek to Cooper Lake while the remainder of Stetson Creek flow is provided for flushing. Gate, valve, and other water release settings need not be adjusted from November through April. Lake will be lowered to EL 1,160 during construction. Per the Settlement Agreement, the MIF will be determined annually by the Interagency Committee. Based on the estimated total flow at the diversion site, approximately 0.2 cfs on average is available to be released over an average year. Therefore, for use in this Feasibility Report, the MIF in Stetson Creek will be constant throughout the year and will be the maximum amount remaining (i.e., 0.2 cfs) after the required 18,285 ac-ft to Cooper Lake through the Diversion Pipeline in an average year. When necessary, Cooper Lake will be drawn down to provide the required flow release to Cooper Creek. 3.2 STETSON CREEK DIVERSION STRUCTURE 3.2.1 Hydrology The hydrology of Cooper and Stetson creeks was assessed in the August 2004 Potential Cooper Creek Protection, Mitigation and Enhancement Measures (PME) Report developed by MWH for Chugach Electric. As stated in the PME Report, U.S. Geological Survey (USGS) Gage 15260500 was located on Stetson Creek close to its confluence with Cooper Creek. The two sites considered in this Feasibility Study for the Diversion Dam were a significant distance upstream of the historic gage and, therefore, required adjusting the hydrology at the Diversion Dam sites based on the reduced drainage area. The drainage area for the Diversion Dam site selected in this report (Site 2 as indicated in paragraph 3.2.2.2.1) is about 7.7 square miles, compared to the entire drainage area at the USGS gage of 8.6 square miles. Thus, the flow at the USGS gage was reduced by about 10% to make it applicable to the Diversion Dam. Therefore, the Stetson Creek MIF could be met by flow not captured by the Diversion Dam or “from the total amount of water available for release to Cooper Creek” as indicated in the Settlement Agreement (i.e., from the 10,256 ac-ft volume). Stetson Creek flow data measured at the USGS gage and estimated at the chosen Diversion Site are presented in Table 3-1. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-4 Feasibility Report – Final 14 March 2011 Table 3-1 Estimated, Average Monthly Stetson Creek Flow at USGS Gage 15260500 and Diversion Dam Site Month Average Flow at USGS Gage 15260500 (cfs) Estimated Average Flow at Diversion Dam (cfs) January 10.4 9.3 February 8.5 7.6 March 5.9 5.3 April 8.9 7.9 May 39.4 35.3 June 83.3 74.6 July 55.4 49.6 August 32.2 28.9 September 30.5 27.3 October 32.2 28.8 November 21.8 19.6 December 13.5 12.1 Key: cfs – cubic feet per second USGS – U.S. Geological Survey Table 3-1 was developed based on the hydrologic analysis of Cooper and Stetson Creeks in the PME Report. The percentage of flow at the mouth of Cooper Creek estimated to come from Stetson Creek, developed in the PME Report, was applied to an extended period of record for flows at the mouth of Cooper Creek. The period of record was extended from that in the PME Report to also include data from 1998 through 2008. Average Stetson Creek flows listed in Table 3-1 result from applying the estimated percentage in the PME report to the average monthly flows for the extended period of record. For the purposes of this report the flows in Table 3-1 were reduced 10% to obtain flows at the Diversion Dam. Thus, the design flow of 110 cfs for the Diversion Pipeline corresponds to about a 1.5% exceedence flow in Stetson Creek at the Diversion Dam (about 120 cfs at USGS Gage 15260500), as presented in Graph 3-1. It should be noted that moving the maximum diversion flow for the Diversion Pipeline from a 1.5% exceedence (110 cfs) to a 5% exceedence (70 cfs) may result in significant cost savings for a relatively small decrease in additional generation by allowing for a reduction in the pipeline diameter. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-5 Feasibility Report – Final 14 March 2011 Graph 3-1 Estimated, Post-Cooper Lake Dam, Stetson Creek Flow Exceedence Curve at USGS Gage 15260500 3.2.2 Hydraulics 3.2.2.1 Annual Diversion The Settlement Agreement states 18,285 ac-ft must be diverted from Stetson Creek to Cooper Lake annually. Of that volume, 10,256 ac-ft is to be released from Cooper Lake to Cooper Creek leaving a net volume of 8,029 ac-ft to be used for power production through the project power plant. The Settlement Agreement also states that on an annual basis some MIF may be directed to be maintained in Stetson Creek “(if any) from the total amount of water available for release to Cooper Creek” (i.e., the MIF is taken from the 10,256 ac-ft volume and does not affect the net volume remaining for power production). No specific MIF quantity is stated, indicating that only that the Interagency Committee will provide direction annually for MIF below the Diversion Dam, “if any”. As shown in Table 3-2, only about 0.2 cfs (average flow) can be maintained in Stetson Creek as MIF, if 18,285 ac-ft is diverted, without taking additional MIF from the Cooper Creek release volume (i.e., 10,256 ac-ft). Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-6 Feasibility Report – Final 14 March 2011 Table 3-2 Average Monthly Diversion Flows Month Flow at Diversion Dam, Average (cfs) *Stetson Creek MIF (cfs) Diversion Flow (cfs) Diverted Volume (ac-ft) January 9.3 0.2 9.1 550 February 7.6 0.2 7.4 410 March 5.3 0.2 5.1 310 April 7.9 0.2 7.7 450 May 35.3 0.2 35.1 2,150 June 74.6 0.2 74.4 4,420 July 49.6 0.2 49.4 3,030 August 28.9 0.2 28.7 1,760 September 27.3 0.2 27.1 1,610 October 28.8 0.2 28.6 1,750 November 19.6 0.2 19.4 1,150 December 12.1 0.2 11.9 730 Total - - -18,320 * Indicates the average MIF without reducing the volume released from Cooper Lake to Cooper Creek. Releasing this flow continually is not practical or suggested. Two points should be made relative to this table. First, the flows in Table 3-2 are average monthly flows recorded over a period of 65 months. Based on the average daily record for the period it is estimated that there were a total of 22 days (about 4 days per year) that exceeded the proposed maximum diversion of 110 cfs for a total “lost” volume past the Diversion Dam of 860 ac-ft or about 170 ac-ft per year. (It should be noted that about 25% of that 5+ year volume occurred during one day.) That would leave about 7,860 ac-ft available for power production annually. If 70 cfs were the maximum diverted through the Diversion Pipeline then about 4,800 ac-ft would be “lost” to generation or about 960 ac-ft per year, leaving about 7,070 ac-ft annually for power production. The second point is that it is assumed that about 11% more flow than flows into the Diversion Dam site, as indicated in Table 3-2, is added by accretion below the Diversion Dam or nearly 3 cfs on average at the mouth of Stetson Creek, providing measurable MIF below the point of diversion. Lastly, it should also be noted that the drainage area for the considered alternate sites for the Diversion Dam was not significantly greater than the chosen site (i.e., Site 2 above the falls as indicated below); thus there is no significant improvement in minimum flow expected for the alternate site. 3.2.2.2 Intake Design Design of the intake at the Diversion Dam is based on inlet control. Sufficient submergence is required to pass the required flow through the inlet to the pipe. To achieve this depth the crest of Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-7 Feasibility Report – Final 14 March 2011 the Diversion Dam must be 8.5 feet above the invert of the Diversion pipe. Air entrainment and vortexing are not a concern with this option as they do not affect the discharge capacity significantly and there is an air inlet/outlet pipe provided immediately downstream of the Diversion Dam. Careful forming of the intake can reduce the height required but for the Feasibility Report a more conservative design is appropriate. 3.2.2.2.1 Siting Alternatives Five different sites along Stetson Creek were considered for the Diversion Dam. These sites were selected for consideration based on: topography, hydraulic head, observed site conditions, site access, potential geologic and avalanche hazards, and the constructability of the associated Diversion Pipeline alignment. During the geotechnical field investigation, two sites were chosen above the others due to the potential for hydraulic head and more favorable geotechnical conditions at these locations. These two sites, Site Alterative 1 (Photo 3-1) and Site Alternative 2 (Photo 3-2), were more favorable because they exhibited better foundation conditions, showed fewer signs of slope instability, and allowed for a more constructible Diversion Pipeline alignment. In addition, abutment slopes, while still very steep, were less steep than some locations, thus improving constructability and site access when compared to other locations. In terms of hydrologic flow (i.e., drainage basin size), there was little difference between any of the alternatives so the difference in the total amount of water available for diversion at the different sites was not a deciding factor. Site Alternative 1 is about 1.0 mile upstream of the confluence of Stetson and Cooper Creeks; Site Alternative 2 is about 1.2 miles upstream of the confluence. For comparison, the historic USGS Gage 15260500 was about 0.3 miles upstream of the confluence. There is a natural falls about 60-feet high between Site 1 and Site 2. The falls account for about half the elevation difference – the invert of the creek is about EL 1,304 at Site 1 and EL 1,424 at Site 2. The additional elevation at Site 2 has beneficial effects on the design of the pipeline. More hydraulic head allows for opportunity to reduce the pipe size or to make a micro-hydropower unit on the Diversion Pipeline more financially attractive. In addition, Site 2 also has shallower slopes on the valley walls than at Site 1, making construction of the Diversion Dam at this location safer and easier. The length of the pipeline is effectively the same for Site 1 and Site 2, because the higher elevation of Site 2 allows the pipeline alignment to avoid some of the knobs and gullies above the confluence of Cooper and Stetson Creeks. For these reasons, Site Alternative 2 was chosen as the location for the Diversion Dam. It should be noted that additional reductions in the pipeline length may be achievable at the final design with the Site 2 location with the inclusion of a flat section(s) of pipeline balanced by a short section(s) of steeper grades. The rigorous hydraulic design needed to optimize the pipeline alignment was not part of the scope of this Feasibility Report, and because additional reductions in the length of the pipeline are not guaranteed, the alignment presented in this report is considered appropriate for feasibility planning and costing. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-8 Feasibility Report – Final 14 March 2011 Photo 3-1 Diversion Dam Site Alternative 1 – Elevation 1,304 Photo 3-2 Diversion Dam Site Alternative 2 – Elevation 1,424 Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-9 Feasibility Report – Final 14 March 2011 3.2.3 Sizing and Layout The Diversion Dam for the 110 cfs alternative is sized based on the minimum submergence necessary over the Diversion Intake of 10 feet, as described in Section 3.2.1. To minimize excavation for the Diversion Dam, and given that the bed of the creek at this location is hard rock, the invert of the intake was set at the creek bed elevation of 1,424. With a 36-inch diameter Diversion Intake, the minimum required pool elevation is 1,437. Assuming at least a full pool is maintained at all times and that the head over the spillway crest would vary throughout the year, the spillway crest was also set to this elevation. A larger intake could be considered later to reduce this height further or provide a larger safety factor for vortexing. To ensure stability of the structure with this reservoir depth, the spillway face was set on a 0.5 horizontal to 1.0 vertical slope, as shown in Section G on 2011 Figure F-6. The spillway width was set at 35 feet to minimize excavation. The spillway is sized to pass the 100-year flood, about 770 cfs. This corresponds to about 10.5 feet of head over the spillway crest, setting the sidewall height at EL 1,448, as shown on 2011 Figure F-6. The intake channel would extend about 22 feet upstream and be protected by a trashrack. The top of sidewalls of the intake channel would extend to the top of the dam sidewalls, EL 1,448, or higher as required to retain the hillside. The invert of the intake channel would match the Diversion Intake invert, EL 1,124. The trashrack would extend the full height of the channel. If a smaller design flow, in the range of 70 cfs is selected, the Diversion Dam would be sized based on the minimum submergence necessary over the Diversion Intake of only 8.5 feet. As with the larger alternative the invert of the intake was set at the creek bed elevation of 1,424.0. With a 32-inch diameter Diversion Intake, the minimum required pool elevation is 1,432.5. For flows larger than the design discharge flow would pass over the spillway. As the flows increase the entire structure would be inundated. The detailed design of the dam must be stable under complete submergence. The intake channel weir would extend about 15 feet upstream and be protected by a trashrack. The top of sidewalls of the intake channel would extend to EL 1,440, or higher as required to retain the hillside. The invert of the intake channel would match the Diversion Intake invert, EL 1,124. The trashrack would extend to the top of the sidewalls. During the winter months ice will form on the surface of the pond created by the Diversion Dam. Depending on the length of time temperatures are below freezing and the flow rate in the creek, there may be a significant buildup of ice on the trashrack and within the inlet. Because of this polyethylene trashracks will be investigated to minimize ice accumulation. Because the flow is fairly low in the winter some buildup of ice should not affect the capacity of the inlet. However, it is possible that the trashrack could ice over completely and may shut off all the flow to the Diversion Pipeline. Since there is no access to the site in the winter, the trashrack will be designed to withstand a substantial ice load and a head differential of about 15 feet. This will allow the trashrack to withstand a little over a full-pool in the reservoir with a dry intake channel. Since flows are low in the winter it does not appear necessary to design for a head differential greater than this, as the reservoir is not likely to be above full-pool in the winter. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-10 Feasibility Report – Final 14 March 2011 The 36-inch diameter sluice would pass a little over a 2-year flood, about 260 cfs, with a full pool. It was assumed that the most advantageous time to provide flushing flow is during such a flood event, when there is plenty of water for both diversion and flushing. 3.2.4 Flow Control and Monitoring The Diversion Intake gate and sluice gate would be manually operated gates as indicated in the Settlement Agreement. The intake gate would remain in the open position except when the Diversion Pipeline is taken out of service for maintenance or repair. The sluice gate would remain in the closed position except it may be cracked open to provide the required MIF, if any, as determined in consultation with the Interagency Committee. The flow in the Diversion Pipeline would be monitored by a flow meter located at the downstream end of the pipeline. Flow in Stetson Creek would be monitored by a solar-powered stream gauge to be installed just upstream of the confluence with Cooper Creek. 3.2.5 Access Access to the Diversion Dam would be provided via the current access road and the Diversion Pipeline bench. The current access road runs from the Sterling Highway to Cooper Lake Dam. This road would be upgraded as required by the contractor to complete the work as part of the overall construction effort as discussed in Section 3.6. A new vehicular truss bridge (or similar) across the existing spillway west of the dam was included in the 2010 layouts and cost estimate to provide access to the Diversion Pipeline bench. A bridge is no longer necessary and has been removed from the design. It is about 1.8 miles from the Cooper Lake Dam to the Diversion Dam site along the Diversion Pipeline. The pipeline bench will be hydroseeded at the completion of construction; however, it is not expected that maintenance will be performed on the bench to maintain vehicle/equipment access to the Diversion Dam. Helicopter, ATV and foot access is anticipated to be the primary operating access method. The Diversion Dam would likely be completely inaccessible from about October through April due to snow. 3.2.6 Construction Construction issues and constraints, and construction scheduling are discussed in Section 4.0. In general, construction sequencing would require substantial completion of the construction of the pipeline bench before construction can begin on the Diversion Dam. There is some flexibility in the construction sequencing for the pipeline in relation to the Diversion Dam depending on the methodology used by the construction contractor. Delivery and placement methods for concrete are likely to be by truck and concrete pump. The selected contractor would either utilize established concrete batch plants in the project vicinity for production and delivery of concrete, mobilize a small batch plant for on-site production near the Cooper Lake Dam, or site mix concrete in trucks from dry, pre-mixed, concrete, 1 cubic yard supersacks. Helicoptering of batched concrete from near the Sterling Highway, or other location in the vicinity of the Project, to the Diversion Dam may also be a viable concrete delivery method. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-11 Feasibility Report – Final 14 March 2011 3.2.7 Maintenance Maintenance activities at the Diversion Dam are expected to be seasonal. As snow usually covers the area from October through April, it is expected that the Diversion Dam must operate without maintenance during this period. When the area thaws in May, Chugach staff can access the Diversion Dam via the pipeline right-of-way or by helicopter or foot to reset the gate (if necessary), sluice the reservoir, clean the trashrack, remove any debris on or near the facility, and repair any damage that may have occurred over the winter. As discussed above, the sluice gate and Diversion Intake slide gate would be able to be operated manually. Hand rakes to clean the trashracks, chainsaws, shovels, and other tools to remove debris, and any tools necessary for repairs would have to be brought in with Chugach staff. The Diversion Dam should be inspected for damage and to clean the trashrack periodically from May through September. Particular attention may be required in the fall during the leafy season to clean the trashracks. Additional visits by Chugach staff may be required to adjust the Diversion Intake gate based on flow requirements. Before winter begins, Chugach staff would perform a final inspection of the Diversion Dam, removing debris, cleaning the trashrack, making final repairs, and setting the Diversion Intake gate to its winter setting. 3.3 STETSON CREEK DIVERSION PIPELINE 3.3.1 Pipeline Hydraulics The flow in the pipeline can be controlled either from the downstream end (outlet control) or from the upstream end (inlet control). The two control methods are discussed below. 3.3.1.1 Outlet Control Feasibility level hydraulic calculations were conducted for verifying the required size of the pipeline needed for a maximum flow of 110 cfs with the alignment shown on 2010 Figures F-7 through F-15. Using uniform slopes between 2.8% and 0.7%, a pipeline with an inside diameter of 36-inches is required. For a maximum diversion flow of 70 cfs the inside diameter could be reduced to 32 inches. An analysis of flow in the pipeline indicated that the pipe would flow partially full in the section of a 2.8% slope and flow full above 80 cfs in the pipe reach of 0.7% slope. At higher flows a hydraulic jump would occur near the change between these two slopes. The air entrained by the hydraulic jump would travel down the 0.7% slope section restricting its ability to carry flow. For flows higher than about 80 cfs, the pipe diameter would have to be larger than 36 inches to maintain pipeline conveyance. In order to maintain full pipe flow conditions such that air entrainment problems are avoided, the pipeline would require pressure control at the downstream end. A pressure sustaining valve (PSV) would be used to maintain positive pressure within the pipeline, with a minimum flow of 3 cfs and a maximum flow of 110 cfs. The PSV would need to be constructed within a valve house, located adjacent to the lake at the high water elevation, which would also be the terminus of the pipeline. The valve house would also contain flow control and monitoring equipment and Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-12 Feasibility Report – Final 14 March 2011 provide the controlled discharge to the diversion outfall. This method of flow control is more costly and will not be pursued further in this report. 3.3.1.2 Inlet Control Alternatively, the flow in the pipe could be controlled from the upstream at the Diversion Dam. For this case the flow in the pipe would be open channel with segments flowing full under high flow conditions. Standpipes would be provided along the pipe line at breaks in grade to allow air to freely enter/or exit the pipeline. The pipeline profile would be adjusted to provide a uniform 1.75% grade to limit the number of standpipes to be provided. 3.3.2 Pipeline Materials and Routing HDPE and steel pipe were investigated for feasibility costing, with HDPE pipe being considerably more cost effective than steel pipe for this phase of investigation. For this Feasibility Report, 42-inch, SDR 15.5 HDPE pipe was selected for the pipeline material. SDR 15.5 pipe has a pressure rating of 110 pounds per square inch (psi) and an inside diameter of 36.25-inches. Anchorage pipe suppliers estimated a steel pipe cost of roughly twice the cost of HDPE pipe for 36-inch ID pipe. An approximate pipeline alignment is shown on 2011 Figures F-7 through F-15. For feasibility design, it was assumed that uniform grade is preferable to varying grade to maintain efficient flow control. The alignment shown closely follows the alignment used for the field investigations discussed in Section 2.0 and represents a most probable overall length. It is expected that this alignment will be modified during final design to establish a final uniform grade and to minimize constructability issues from topographic features and impact to wetlands. The pipeline would be placed either within, or on top of, an associated bench as discussed below. For the majority of the alignment, the pipeline would be buried with a minimum cover thickness of 3 feet. Where the pipeline is constructed in the Stetson creek gorge, conditions may be such that the pipeline would be placed on top of the pipeline bench to reduce rock trenching. 3.3.3 Flow Control and Monitoring For the cost estimate contained in Section 6.0 we have assumed inlet control requiring no power to the site and no downstream PSV. A flow meter is required per the Settlement Agreement to monitor flow from Stetson Creek to Cooper Lake. With the inlet control option the chance of a rupture is reduced as there is very little internal pressure on the pipe. For this alternative no automated gate is provided at the Diversion Dam. 3.3.4 Pipeline Bench/Pipeline Construction Access A bench would be constructed along the pipeline alignment to provide construction access to the Diversion Dam, the pipeline itself, and the diversion outfall. The width of the bench would be sufficient to provide access during construction activities and for maintenance use if maintained Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-13 Feasibility Report – Final 14 March 2011 by Chugach. The bench would be constructed similar to an outsloped forest road. The bench surface would be canted to a drain to the downhill side, eliminating the need for ditch construction and relief culverts. Outsloping the pipeline bench allows the construction volume to be minimized as well as allowing for a reduction in runoff turbidity and erosion if properly constructed and maintained. Gravel surfacing would not be placed on the pipeline bench, instead, the bench will be revegetated at the completion of construction. Gabion basket retaining walls are expected at select locations within the Stetson Creek gorge where side slopes are very steep (0.5H:1V) or where deep gullies must be crossed. At creek and gully crossings, culverts would be placed to convey flow beneath pipeline. The alignment shown on the drawings intends to minimize construction within or adjacent to known wetland areas. 3.3.5 Spillway Bridge A pre-manufactured vehicular truss bridge was previously considered to access the Diversion Dam. However, this bridge was eliminated in later designs to reduce overall construction costs and minimize access to reduce access to the roadless area of the Chugach National Forest. It is anticipated that the Diversion Dam may still be accessed along the route of the pipeline by a foot or ATV trail without the bridge. 3.3.6 Construction Construction issues and constraints, and construction scheduling are discussed in Section 4.0. The majority of the pipeline bench would be constructed as a cut-to-fill, with excavation material from the uphill side placed as fill on the downhill side. Where the bench is located within the Cooper Creek drainage, typical permanent cut and fill slopes in common material are expected to be 2V:1H. Where the bench is located within the Stetson Creek drainage, it would be constructed as a cut-to-fill only in locations where the existing side slopes are flatter than about 2H:1V. For much of the upper portions of the bench (above EL 1,350), the bench would be constructed as an excavation only, requiring removal of excavated material for use as fill in lower sections of the alignment. This pipeline cut above Stetson Creek would be difficult. Some to a considerable amount of blasted cut material can be expected to fall down the steep hillslope below the cut, some to the creek. The pipeline would be constructed as a trench and backfill operation after completion of the bench has been established. 3.3.7 Maintenance Maintenance of the pipeline is expected to be seasonal. As snow usually covers the area from October through April, it is expected that the Diversion Dam and the pipeline would operate without maintenance during this period. Low flow during the winter will decrease the water velocity in the pipeline and increase the possibility of ice formation in the pipeline. However, because the pipeline is buried and the composition of the pipeline is non-conductive HDPE, the water should remain above freezing in the pipeline. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-14 Feasibility Report – Final 14 March 2011 In the spring, maintenance personnel would conduct sufficient maintenance on the pipeline bench to prevent the establishment of deep rooted vegetation. It is expected that a two-man clearing crew with chainsaws would be sufficient for maintenance. Clearing of drainage culverts, placement of additional fill in problem areas and periodic reseeding along the pipeline can be expected on occasion. 3.4 STETSON CREEK DIVERSION OUTFALL 3.4.1 Hydraulics and Siting The location of the Stetson Creek Diversion Outfall into Cooper Lake would be about 2,000 feet upstream of Cooper Lake Dam to minimize the effect of the colder, diverted water on the warmer, surface water releases from the dam. The Diversion Pipeline would discharge into a head tank or energy dissipation structure connected to the outfall pipe. The outfall pipe connects to a diffuser located on the bottom of the lake to minimize mixing of the colder water with the warmer upper lake water as shown on 2011 Figure F-15. The steep slope of the lake bank (about 20%) is such that a hydraulic jump can be expected within the outlet pipe, thus the outlet pipe would require air venting capability to maintain the design discharge capacity. 3.4.2 Energy Dissipation and Flow Diffusion The energy in the flow in the Diversion Pipeline will be dissipated by passing through the energy dissipation structure before overflowing through the HDPE outlet pipe that carries the flow down the bank of the reservoir to the diffuser pipe on the bottom of the reservoir. The diffuser section would be designed to spread the Stetson Creek water as evenly as possible on the bottom of the lake. The objective is to not disturb the thermocline in the lake. The diffuser section would have several diffuser ports along its length to spread the flow over a sufficiently large area to diffuse the flow energy effectively. A computer model would be run to assess the behavior of the diffuser jets and their effect on the thermocline. Alternatively, the flow could be discharged to a stilling basin located at the top of the reservoir side slope. Water would exit the stilling basin over a side weir and be allowed to cascade down the slope to the lake. This option would obviate the need for any underwater construction. However, to maintain the proper thermal distribution near Cooper Lake Dam, the stilling basin may need to be moved further upstream. This is something that could be investigated during final design to reduce cost. 3.4.3 Construction The foundation of the energy dissipation structure would be constructed of cast-in-place, reinforced concrete on the shore of the reservoir above high water. If possible the reservoir would be drawn down to EL 1,160 prior to installing the pipeline and diffuser section to minimize the depth of construction. The lake shore would be trenched, and the HDPE pipe would be fused and placed in the trench on the required bedding. The diffuser Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-15 Feasibility Report – Final 14 March 2011 section would be fitted with concrete weights and the end of the section would be capped. The pipe would be floated into the reservoir on the required alignment and sunk by opening a valve in the end of the pipe. The pipe would settle to the bottom starting from the off-shore end. The on-shore end of the diffuser section would then be flanged to the end of the pipe. The pipe trench would then be backfilled. 3.4.4 Maintenance The energy dissipation structure should be inspected annually for signs of deterioration, wear and leakage. The diffuser section would not require maintenance, although it should be inspected about every ten years. 3.5 COOPER LAKE DAM OUTLET WORKS 3.5.1 Hydrology and Hydraulics The Settlement Agreement states that 10,256 ac-ft of water from Cooper Lake must be released into Cooper Creek every year to provide warmer water in the creek. The Settlement Agreement also states that 18,285 ac-ft of water should be diverted from Stetson Creek to Cooper Lake every year. This results in 8,029 additional acre-feet available for generation from Cooper Lake through the existing project powerhouse. The Settlement Agreement further states that if no direction regarding the release from Cooper Lake is received from the Interagency Committee, then target instantaneous flow releases and target monthly volumes will be set according to Table 3-3. When these flow releases are compared to the calculated diversions available from Stetson Creek, it is apparent additional drawdown of Cooper Lake will be required January through April. After April the lake will replace the volume deficit from the previous months and gain the additional 8,029 ac-ft of volume for generation. The water temperature data shown in the PME Report and as shown in Graph 3-2 indicates that the lake stratifies during the summer. However, the lake maintains a constant, warmer temperature above EL 1,150. It is for this reason that a single intake is designed with an invert of EL 1,150 while some alternatives from the August 2004 PME study suggested multiple intakes at different elevations. The lake level varies throughout the year. Historically, Cooper Lake fills in the summer and is drawn down in the winter. The changes in inflow and outflow at Cooper Lake, as shown in Graphs 3-3 and 3-4, will exacerbate the lake level drop and rise. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-16 Feasibility Report – Final 14 March 2011 Table 3-3 Targeted Cooper Lake Release Flow, Estimated Average Diversion Flows, and Estimated Cooper Lake Drawdown/Refill Month Diversion from Stetson Creek (cfs) Targeted Cooper Lake Release (cfs) Volume of Drawdown (-) or Refill (+) at Cooper Lake (ac-ft) January 9.1 10.0 -60 February 7.4 10.0 -140 March 5.1 10.0 -300 April 7.7 10.0 -140 May 35.1 10.0 1,540 June 74.4 20.0 3,240 July 49.4 25.0 1,500 August 28.7 20.0 530 September 27.1 20.0 420 October 28.6 15.0 840 November 19.4 10.0 560 December 11.9 10.0 120 Total - - 8,110 3.5.2 Routing Alternatives Two routing alternatives were examined for the Cooper Lake Dam Outlet Works. The Gravity Option is a gravity pipeline cut through Cooper Dam similar to that shown in the PME Report. This option requires significant excavation and rebuilding of Cooper Dam, therefore a Siphon Option was examined to minimize excavation. The Siphon Option routes the pipeline through the spillway at a higher elevation than the intake to minimize the rock cut. The pipeline for both alternatives is sized based on the maximum instantaneous outflow of 30 cfs, prescribed in the Settlement Agreement. Our assumption is that only 10 cfs may be required to be released for lake levels down to EL 1,160, typically occurring at the end of the winter, and 30 cfs can be released when the lake level reaches El 1,170. Using this criterion, the outlet pipe size is reduced (over requiring 30 cfs outflow down to lake EL 1,160) for both the Gravity and the Siphon Options, saving cost. 3.5.2.1 Gravity Option The Gravity Option consists of an excavated channel that would run about 1,000 feet through Cooper Lake to an intake. The channel would be about 8 feet wide, have an invert of EL 1,150, and side slope of 2H:1V. From the intake, a 36-inch steel pipe would run about 260 feet to an Outlet Tower buried in the earthen dam. The intake pipe would be set on an inverse slope, beginning with an invert elevation of 1151 at the intake and terminating at the Outlet Tower at invert elevation 1153. The Outlet Tower would be a 67-foot high, 10-foot diameter, cylindrical tower housing two slide gates – one for the intake pipe, another for the outlet pipe. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-17 Feasibility Report – Final 14 March 2011 Graph 3-2 Cooper Lake Temperature Profiles (2002-2003) Plotted on Average Historical Cooper Lake Levels Graph 3-3 Post-Construction Net Inflow to Cooper Lake versus Historic Lake Levels Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-18 Feasibility Report – Final 14 March 2011 Graph 3-4 Post-Construction Target Discharge from Cooper Lake to Cooper Creek versus Historic Lake Levels At the top of the Outlet Tower would be a 10-foot high, 10-foot diameter, Maintenance Building that would house the gate actuators. The Maintenance Building floor would be at the same elevation as the top of the dam, EL 1,220. The Maintenance Building would be accessible directly from the road on the top of Cooper Dam. The outlet pipe would exit the Outlet Tower to downstream side of Cooper Dam. The pipe would extend about 290 feet downstream to an outlet structure. The outlet pipe and outlet structure would stay buried within the toe of the west hill to avoid damage to the pipeline during spill events. A 9-foot wide channel would be cut into the creek bed from the outlet structure about 580 feet downstream. The channel would drop from invert EL 1,154 at the outlet structure to invert EL 1,150 downstream. The intake and outlet channels would be cut to avoid the cost of piping. The inlet and outlet pipes that would still be required would be encased in concrete with 1H:8V side slopes through Cooper Dam according to common engineering practice. Headloss through the pipeline is kept low to minimize the required head drop and keep the length of pipe to a minimum. Even so, the pipes still require a minimum slope of ¼ percent to facilitate drainage for inspection and maintenance. Both pipes meet this requirement but to do so the pipes would have an inverse slope. This has the additional advantage of minimizing the excavation. However, due to the required elevation of the intake, the pipeline would run under the core of the current earthen dam. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-19 Feasibility Report – Final 14 March 2011 To adequately replace the earthen dam, the cut slope through the dam is assumed to be 3H:1V. A cut slope of 2H:1V would be allowed outside the confines of the dam. This cut slope requirement through the dam allows Cooper Lake Dam to be rebuilt with adequate compaction and inspection. The cut through the dam would lay about half the length of the dam open at the crest. The Gravity Option is shown on 2010 Figures F-3 and F-4. 3.5.2.2 Siphon Option The Siphon Option accomplishes the same function as the Gravity Option by providing flow from Cooper Lake to Cooper Creek. The design flow for the siphon varies from 10 cfs up to 30 cfs. At the lower flow the reservoir is assumed to be at the minimum historic reservoir level of 1159.0. At the higher flow the reservoir is at the highest minimum elevation of 1173.0, as shown in Graph 3-3. The design would not discharge 30 cfs at the lowest lake level. A short sloping excavated channel would run about 100 feet down to the pipe inlet invert at EL 1,154.0. The inlet structure would contain a coarse trashrack and the check valve used for priming the pipeline. From the intake, a 30-inch diameter steel pipeline would slope upstream to a trench through the spillway at 1179.0. The spillway cut would be approximately 33-foot deep through rock. This cut through the spillway would provide significantly less excavation than the Gravity Option while remaining deep enough to avoid vapor lock of the siphon. The pipe would be surrounded with bedding material or concrete encased and the spillway cut would be backfilled with shotrock from the excavation. A concrete cap would be placed over the shotrock fill to bring the spillway back to its original spillway invert elevation. To prevent water from piping through the spillway under the concrete cap, a concrete cutoff wall would be poured, encasing the pipe up to the original spillway elevation. The cutoff wall would be located near the axis of Cooper Lake Dam. The pipe would discharge to an outlet energy dissipation structure and rock lined stilling pool in Cooper Creek downstream of the spillway. To prime the siphon the butterfly valve downstream of the dam would be closed. The pipe would be filled via a 6-inch steel pipe tapped off of the Diversion Pipeline, and tapped to the siphon pipe near STA 7+00. Control for the 6-inch pipe would be provided by a butterfly valve near the Diversion Pipeline. A 1-inch valved standpipe would be tapped off the siphon pipe near the location and routed near the 6-inch butterfly valve to provide to the operator a visual indication of when the siphon pipe has been filled. When the siphon pipe is full, the downstream butterfly valve would be opened to provide the desired flow based on lake level. The Siphon Option is shown on 2011 Figures F-3 through F-5. 3.5.3 Intake Design of the intake is controlled by vortexing and air entrainment. According to Hydraulic Institute Standards for Intake Design, the required depth over the top of the intake pipeline is about 5.5 feet for the design flow of 30 cfs. The Settlement Agreement states the minimum operating level of Cooper Lake is 1,160 feet. For the 36-inch and 42-inch diameter inlets, the inverts of the pipe must be set to EL 1,151 and EL 1154, respectively. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-20 Feasibility Report – Final 14 March 2011 3.5.4 Outlet Design of the outlet is controlled by hydraulic losses in the pipeline and the maximum and minimum design flows. Hydraulic losses in the Gravity and Siphon Options require the outlet to have an invert elevation of 1,154 and 1,153 feet, respectively. To achieve these elevations with the shortest length of pipe possible, the outlet is placed as far upstream along Cooper Creek as possible. For the Siphon Option this is in the creek bed immediately downstream of the dam. From the outlet structure, a channel to the desired elevation in the creek bed must be excavated. For the Gravity Option the outlet would also be immediately downstream of the dam in an excavated, minimally-sloped channel downstream to the hydraulically required outlet point. To protect the outlet from spill during flood events, both outlets are built back into the hill along Cooper Creek. The size of the outlet structure is governed by the maximum and minimum design flows. The outlet structure is currently designed to accommodate the rough hydraulic profile at the minimum and maximum flows. The structure may be reduced in size when the hydraulic profile and design conditions are refined during final design, but the locations in the hillside would likely not change much, requiring slightly longer excavated channels downstream. 3.5.5 Flow Control and Monitoring 3.5.5.1 Flow Control Flow control for the Gravity and Siphon Options is expected to be set manually. As with the Diversion Dam, the Cooper Lake Dam Outlet Works would be inaccessible during the winter, October through April, making manual adjustment difficult unless accessed by helicopter. During that time the required release from Cooper Lake is constant (10 cfs), except for a slightly higher flow requirement (15 cfs) in October. However, the lake level changes appreciably during that period. Similar to the Diversion Dam, if the control gates, for the Gravity Option, and the control valve, for the Siphon Option, are fixed at the end of September for the winter, the flow through the outlet works would vary substantially. The varying discharge may be an unacceptable trade-off as it would reduce generation. Bringing power into the site may be considered during final design to reduce winter manual operation and optimize flow releases to Cooper Creek. 3.5.5.2 Monitoring The Settlement Agreement states that the flow release from Cooper Lake to Cooper Creek must be monitored. It also states that flows diverted from Stetson Creek and flows and temperature at the mouth of Cooper Creek must be monitored. This data must be recorded at least once every 15 minutes. To ensure compliance, the Settlement Agreement stipulates that Chugach must provide flow data for the flow release from Cooper Lake to Cooper Creek to the Interagency Committee on a quarterly basis. Recording and telemetry equipment can be provided at the Diversion Dam and Cooper Lake Dam Outlet Works by using solar power with a battery backup and satellite data transmission. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-21 Feasibility Report – Final 14 March 2011 3.5.6 Construction 3.5.6.1 Gravity Option Construction of the Gravity Option would require an open cut through Cooper Dam about 450 feet top width. During construction, the reservoir would be dewatered to EL 1,160. An open trench would be cut through the reservoir to construct the inlet channel and lay the inlet pipe. The open trench would be laid back at a 2H:1V slope until reaching the toe of Cooper Dam. A trench would be cut through the dam down to about EL 1,147 at the lowest point, at the center of the dam. The trench would be laid back through the dam at a 3H:1V slope to obtain proper compaction and quality control. The dam core, shell, filter blanket, and all other material would be removed, as necessary, to achieve the required slope, segregated and stockpiled for reconstruction of the dam. The cut required for the Gravity Option requires excavation below the existing core of the dam. The pipeline through the dam would be encased in concrete. Outlet Tower construction would begin once the cut through the dam is complete. The Outlet Tower would be formed and cast in place. Due to the height of the structure it is likely the Outlet Tower would be constructed in 12- to 15-foot high lifts. Once adequate concrete strength is achieved on lower lifts, the earthen dam would be rebuilt to about the height of the lift so that lateral support for the structure is provided by the surrounding dam material during construction. When Cooper Lake Dam is rebuilt over the outlet pipeline and around the Outlet Tower, the new core would extend deeper than the existing core. Once Cooper Lake Dam is rebuilt, it is expected that the equipment and finishing work for the Outlet Tower would be completed concurrently with the remainder of the inlet and outlet piping and channels upstream and downstream of the dam. Construction of the outlet structure, outlet channel, the remaining outlet pipeline, and finishing work for the Outlet Tower would be completed concurrently, as permitted by the single-lane access road to the site. The remaining outlet piping would be trenched through hillside west of the dry, upstream end of Cooper Creek, near the dam. This section of pipe would be backfilled with native material to the required compaction. Rip rap would be placed along the east side of the cut to protect the pipe, outlet structure, and hillside from erosion during spill events. While it is technically possible that the Gravity Option construction could be completed in one season (May to October), such a schedule contains significant delay risk. It is likely that construction of the separate facilities would interfere with each other and significantly retard the schedule. Construction of the Gravity Option is expected to extend to two construction seasons and should be planned accordingly. While this option is technically feasible, there is a risk of uncovering unforeseen conditions in the dam that may require immediate and possibly costly repairs and reconstruction. These conditions cannot be anticipated, therefore a higher owner construction contingency may be warranted. If such difficulties were encountered the construction would likely be delayed by a year or longer. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-22 Feasibility Report – Final 14 March 2011 3.5.6.2 Siphon Option Construction of the Siphon Option would require a deep cut through the rock spillway at Cooper Lake Dam, but would have substantially less total excavation than the Gravity Option. During construction the reservoir would be lowered to EL 1,160, if possible. An open trench would be cut in the reservoir to excavate the inlet channel and lay the inlet pipe. The open trench would be laid back at a 2H:1V slope until reaching the siphon inlet. From the siphon inlet the siphon pipeline would likely be installed by rock trenching methods through the spillway to a point downstream of the dam (2011 Figure F-3). The trench would likely be cut with a minimum width for efficient construction of the pipeline. The outlet of the siphon would be constructed within the existing channel of Cooper Creek approximately 150 feet downstream of the dam. A siphon outlet trench would be constructed from the siphon outlet to a point where the diverted water would daylight at an approximate elevation of 1,150 feet. The outlet trench would be laid back at a slope of approximately 2H:1V to 2.5H:1V, depending on the soils encountered. The preferred method for laying the pipe through the spillway should be investigated further in final design. The siphon trench is expected to encounter glacial outwash and till upstream of spillway, slate within the spillway and colluvium overlying fine grains soil downstream of the spillway. Standard soil trenching approaches are anticipated within the soil portions of siphon pipeline alignment. The pipeline within these portions of the siphon pipeline will be seated in granular pipe bedding and backfilled with select backfill placed as structural fill. Rock trenching methods, including controlled blasting, hydraulic rock breakers,or other rock excavation techniques., will be required within the existing spillway. This portion of the siphon will be fully encased in lean concrete to approximately 1-foot above the pipe (2011 Figure F-5). The remainder of the rock trench will be backfilled with shotrock from excavation. A concrete cap would be placed over the rockfill to bring the spillway back to its original elevation. A concrete cutoff wall would also be placed, encasing the pipe up to the original spillway elevation, near the axis of Cooper Lake Dam. It is more likely that the Siphon Option could be completed in one season (May to October); however, there is also significant delay risk. Little interference is expected with the construction of the Diversion Dam and Diversion Pipeline, though access to the Diversion Pipeline right-of- way will require access across the upstream end of the spillway. Since the construction of the diversion dam and pipeline is likely to take place concurrently with the construction of the outlet facilities, project planning will be an essential part of completing the project without delays. Careful coordination between construction crews will be required in order to construct the siphon outlet without impairing the access to the diversion facilities. 3.5.7 Maintenance Maintenance of the Cooper Lake Dam Outlet Works is expected to be periodic. As snow usually covers the area from October through April, it is expected that the Outlet Works would operate without maintenance during this period other than to periodically adjust the outlet valve/gate. When the area thaws in May, Chugach staff would be able to access the facilities to maintain the Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-23 Feasibility Report – Final 14 March 2011 gates or valve, clean the trashrack, remove any debris on or near the inlet, outlet, or Outlet Tower, and repair any damage that may have occurred over the winter. The slide gate and butterfly valve are expected to be manually operated. Chugach staff would maintain the gates and valves throughout the spring and summer, and prepare the gates and valves for winter. Boats and hand rakes would be used to clean the trashracks. The inlet, outlet, outlet tower, and any exposed pipeline should be inspected for damage and the trashrack should be cleaned periodically from May to September. Flows would be periodically adjusted manually to meet the flow release regime specified in the Settlement Agreement or developed with the Interagency Committee. Before winter begins, Chugach staff would perform a final inspection of the Outlet Works, removing debris, cleaning the trashrack, and performing final repairs and maintenance. 3.6 SITE ACCESS Access to the site is via an existing 4.5-mile, single lane gravel road from the Sterling Highway near Cooper Landing to the Cooper Lake Dam. The current condition of the road is acceptable for periodic, four-wheel drive, light-vehicle access to the site, however there are several wet areas, sharp curves, and steep grades that would limit delivery of equipment and materials to the site without improvement. For this Feasibility Report it was assumed that the access road will be provided in an as-is condition and the contractor will be required to make improvements to the existing road he deems necessary to bring his equipment and materials into the site. This alternative may have the ability to save some costs, but given the condition of the road, substantial costs may be required. At the end of construction the contractor would be required to leave the road in as-good or better condition than he found it at the beginning of construction. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-1 Feasibility Report – Final 14 March 2011 4.0 CONSTRUCTION SCHEDULE AND CONTRACTING APPROACH 4.1 ISSUES AND CONSTRAINTS 4.1.1 Construction Staging Overall high-level construction staging and scheduling will be developed once the overall contracting strategy and implementation approach are finalized and accepted by Chugach. Considerations for construction staging include: Improvements to the site access road must be performed before major construction activities commence. Development of staging areas for contractor mobilization should be developed in conjunction with any improvements to the site access road. Construction of hydraulic structures must be coordinated with Cooper Lake level planning and the seasonal flow characteristics of Stetson Creek. Plans for staging of contractor activities, procurement, and delivery must be developed to limit the impact construction timing and/or project duration. 4.1.2 Access Considerations and Laydown Areas The project site is constrained, both in terms of access and in terms of laydown space. Access is limited to a single lane, 4.5-mile long, gravel road from Cooper Landing. Improvements would be made to this road such that construction equipment and materials can be transported into the site. However, these improvements would be limited to improvements in grading and the gravel surfaces, mitigation of tight turns that may limit delivery of heavy equipment (lowboy vehicles) or materials, and mitigating problem drainage areas. The access road would not be widened to allow two-way construction traffic, thus radio communication would be utilized for construction traffic control. Early delivery of equipment, to take advantage of the maximum extent of the construction season may require pulling delivery vehicles through impassable areas with tracked equipment. As currently planned, no specific road improvements would be required by the contractor beyond compliance permitting, environmental and other appropriate restrictions. The contractor will be allowed to use the road as-is. The contractor will be required to restore the road to no worse than its pre-existing condition at the end of the project. The contractor would likely make some road improvements, but would limit them only to those needed for workable access. At the conclusion of the Project, Chugach would be left with a road that would be in no worse condition than they have now. Lay down area is limited at the site, so use of off-site storage, just-in-time and second shift deliveries, off-site staging of personnel, and other proven techniques should allow contractors to progress the site work in a timely manner. Limiting the number of contractors working on-site, as provided for in the contracting strategy contained herein, would also reduce the risk of schedule impacts from multiple contractors affecting and delaying each other. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-2 Feasibility Report – Final 14 March 2011 4.1.3 Schedule Constraints Time is of the essence for this project. Chugach is targeting project completion by fall 2015.The contracting strategy should be based on implementing and completing the Project, within the allowable time frame, or as soon as reasonably achievable should this timeframe not be feasible. Considerations for scheduling include: Permitting. The permitting requirements as indicated in Section 5.0 control the construction start date for most of the project activities. At this time, Chugach is working toward having permits in place no later than February 2013. To our knowledge, no major impediments, in terms of permitting or regulatory approvals, have been identified and reported. However, it is recognized that overall implementation, and specifically the implementation schedule, are contingent upon timely actions and approvals by the permitting and regulatory agencies. Limited construction season. The project site is located in a relatively remote location, subject to significant snowfall and prolonged winter conditions. The practical construction season is limited to mid-May through mid-October and may be shorter with early onset, or late departure of winter conditions. Snow clearing along the access road in some locations may be required. Long lead time items. Design work needs to be completed within sufficient time to allow for procurement of long lead time items. Long lead time items include: –Procurement time for HDPE pipe in the quantities required for this project is about 12 weeks. –Procurement time for large valves and gates is 3 to 4 months. Working hours. Given the remote location of the project, it should be expected that extended working hours, such as 6-10s, double shifts and/or Sunday work would be utilized to partially mitigate the short construction season and expected weather delays. 4.1.4 Environmental Considerations Environmental considerations include: Sediment in Stetson Creek. It can be assumed that sediment discharge into Stetson Creek is not acceptable. This will constrain the construction methods where the pipeline is located above Stetson Creek. Side casting of pipeline excavation is not likely to be feasible, thus the Opinions of Probably Construction Cost (OPCC) includes the cost of removing excavated material for stockpiling, or use as fill in the flatter terrain of the Cooper Creek drainage. However, it is impractical to assume that all excavated material will be contained; some amount of disturbed material should be expected to be lost down the hillslope to the creek, even with the contractor’s best efforts. Wetlands. The Stetson Creek pipeline will require construction in the vicinity of isolated wetland areas. To the extent possible, wetlands will be avoided by adjusting the pipeline alignment; however, placement of fill at creek crossing locations will undoubtedly affect wetlands. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-3 Feasibility Report – Final 14 March 2011 Cofferdam/Temporary Diversion in Stetson Creek. To construct the Diversion Dam, it will be necessary to perform work in the creek and control the water to allow construction in the dry. The diversion could be built in halves by diverting the creek to one side by sandbagging and channelizing it and then moving it to the opposite side when half the structure is constructed (with a diversion through it). Reduced flows historically begin in August when average flows are reduced to less than 30 cfs as shown in Table 3-3. Flows in July average about 50 cfs and would be more difficult to divert. However, given the short working seasons, the contractor may need to get into the creek early (June) requiring a more substantial and higher capacity temporary diversion. Dust and Noise. Given the location of the construction site, the generally accepted methods of dust and noise controls associated with projects of this scale will be sufficient to mitigate these impacts. 4.1.5 Weather Considerations Weather considerations include: Construction Season. As indicated above, the practical construction season due to winter weather conditions is mid-May to mid-October. Construction weather delays. The project site is located in an area with high precipitation, and weather delays can be expected throughout the construction season. Such conditions may include excessive precipitation requiring temporary shutdown of trenching, grading or pipe laying work; and fog or wind conditions limiting work conducted with helicopter support. Construction scheduling presented later in this report includes a reduction in the actual work days achievable to properly account for this limitation. 4.2 NUMBER OF CONTRACTS AND CONTRACTORS The lower bound of the number of contractors needed to complete all the work scope described herein is one single contractor and there are a sufficient number of contractors in Alaska that have the capability taking on the entire project. Given the limited access to the site and the interconnection between the major construction items, a single contractor is the most logical approach. The opinion of probable construction cost (OPCC) and schedule developed for this feasibility study as presented later in this document are based on a recommended single contract approach. It should be noted that the OPCC identifies 8 major work items, so the theoretical upper bound would be on the order of 8 separate contracts. As the number of contracts increases, the overall costs to contract the work, the overall administrative costs, and the overall contract management costs increase, and the risk of scheduling delays and construction cost escalation for the owner also increases. Should multiple contracts be considered, contract scope should be bundled so that contractors are generally working within their core competencies. Work should also be combined so as to minimize disruptions to a continuous flow of work; and contracts should be coordinated to avoid different contractors working in the same area, or conducting work in a Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-4 Feasibility Report – Final 14 March 2011 common access corridor that may affect the execution of work in a different area of the project site. Thus, this particular project could be segregated into two major construction groupings: Road and Pipeline Construction. This group would include improvement of the main access road, construction of the pipeline, and staging areas. Depending on the progress of permitting and design efforts, this work group could be segregated into two contracts: one contract for improvement of the access road, and one contract for the remaining work. The main access road work could easily be accomplished by a small, local contractor, whereas the pipeline construction work is likely to require the resources available with larger regional contractors. Hydraulic Structures. This group would include construction of the Stetson Creek Diversion Dam, the pipeline outfall structure, and the Cooper Lake Dam outlet structure. Also included in this group would be instrumentation and controls. Alternately for multiple contracts, it is most logical to have different contractors for each construction season (i.e., two seasons). This eliminates the unavoidable interferences caused by two contractors working on the same site simultaneously. As stated above, a single contractor is the most logical approach for this project given the project constraints with construction during 2013 and 2014. However, should unforeseen design and/or permitting issues arise that delay final approval of the hydraulic structures and/or the pipeline (or other conveyance method), the ability to segregate construction into these groupings may allow the overall entire project to still be constructed in a timely manner by issuing separate contracts. 4.3 ENGINEERING DESIGN RESPONSIBILITIES There is some flexibility as to who performs the detail engineering – the Project engineering team, or the contractor (or their subcontractors). When scoping this feasibility study, an Engineer-Procure-Construct (EPC) contracting approach was considered as a potential option for shifting design efforts to the contractor(s) as a method of streamlining the construction effort. However, given the permitting constraints which will require the design of the hydraulic structures to be at a 60% to 90% level prior to approval action by permitting agencies, it was determined that an EPC approach is not appropriate for this project and would not shorten the schedule or reduce the cost. Therefore, it is recommended that a Design-Bid-Build (DBB) approach be utilized and that the design effort be completed primarily by the Project team to the level of detail sufficient for permitting and construction bidding. This will allow the design to commence immediately when a decision to proceed with the Project, if such is decided, is given by Chugach. Chugach has an open dialog with the FERC in order to expedite the design process. FERC has requested that the final design include: Appropriate erosion protection (riprap) due to known wave action. Temporary slopes for the siphon excavation. Stability and sliding analysis of the Diversion Dam. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-5 Feasibility Report – Final 14 March 2011 Stetson Creek diversion concept plans (cofferdam). A final design report six months ahead of the plans and specs, if possible, to expedite review. While primary design responsibilities are recommended to remain with the Project engineering team, there are detailed design activities that can be transferred to the contractor when the project is bid. These items may include, but are not limited to the following: Stetson Diversion creek diversion. Though a reasonable concept(s) will be required and developed by the engineer for inclusion in pertinent permits, the contractor should be left with the responsibility of designing, installing and maintaining a stream diversion to enable constructing the Diversion Structure. This also shifts the risk of the cofferdam to the contractor. Improvements to the existing access road will be the responsibility of the contractor. By allowing the contractor to determine the level of road improvement and maintenance required to support the construction effort, additional responsibility (and thus construction risk) will be transferred to the contractor. 4.4 RECOMMENDED CONTRACTING APPROACH A single construction contract approach is recommended for this project given the constraints and issues listed throughout this report. In order to complete construction in the most efficient manner, both the pipeline work and the hydraulic structure work will need to overlap and/or be conducted concurrently. A single contractor managing equipment, resources and subcontractors will eliminate the inevitable contractor claims that would arise from conflicts that result from trying to execute separate contracts on a common project site. 4.5 SCHEDULE A two-construction-season Project implementation schedule was developed for the Siphon Option. In addition we examined a single season schedule. Though it is technically feasible, a single season schedule can be achieved only under ideal conditions (there is no float) and is fraught with delay risks. In addition, a single season schedule is more costly because it would require double or triple shifting and high cost due to overtime pay premiums. The two season schedule is much more constructable, though still with minimal float. The schedule is provided as 2011 Figure F-17 of this report. The following factors were integral to this schedule as it is currently developed: Time is of the essence. As described above, the overall approach is to perform the engineering and contracting, and manage project implementation, so as to complete the Project in the minimum time reasonably achievable. Technical perspective. The schedule was developed from primarily a technical perspective (i.e., items such as how long will it take to contract to design, fabricate deliver, and install major equipment, and how long will specific site construction activities take). Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-6 Feasibility Report – Final 14 March 2011 Contracting strategy. The schedule was developed based on the overall contracting strategy described above. Implementation considerations. The schedule was developed in consideration of the overall Project implementation considerations described in Section 3.0 above. Permitting and Regulatory. Permitting preparation, review and approval have been included in the schedule with estimated timings and durations based on considerations described in Section 5.0. Project float. The durations for major activities that are shown are considered to be realistic to moderately conservative. As a result, the overall length of time is considered to be sufficient to accomplish the work under a time is of the essence approach, assuming some moderate delays. However, float time per se was not built into individual activities or shown. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 5-1 Feasibility Report – Final 14 March 2011 5.0 PERMITTING 5.1 REQUIRED PLANS AND PERMITS The Stetson Creek Diversion Project has been through a National Environmental Policy Act (NEPA) process, as documented in FERC‘s November 2006 Environmental Assessment. The follow-on approval process for the construction of Stetson Creek Diversion and Cooper Lake Dam Facilities Project is outlined in Article 402 of FERC’s Cooper Lake Project License Order of August 24, 2007. Under the Settlement Agreement included in the FERC License Order, the Project plans should include the following: Required state and federal permits and water rights. Erosion and sediment control and monitoring plan (as also required under Article 302 of the License). Environmental compliance monitoring plan. Fuel and hazardous substance spill plan (as referenced in Article 401). Bird nesting and bear denning avoidance procedures. Management plan regarding public access during construction. The management plan regarding public access during construction should be incorporated into a revised version of the Public Access Control Plan (Article 406) that must be filed with FERC as part of the Article 402 submittal. The revised Public Access Control Plan will be filed with the other components of the Article 402 submittals and will essentially build upon the September 30, 2008 Public Access Control Plan Chugach has already developed. The plan will be updated to address: permanent(and temporary) public access for the new pipeline right-of-way within a 50- foot right-of-way corridor; locations and design of new access gates; and procedures and methods for maintaining and monitoring gate effectiveness, as well as alternative procedures if gating proves ineffective for controlling unauthorized motorized vehicle access. Article 401 of the License requires three additional construction-related plans referenced in the Settlement Agreement for any Cooper Lake construction projects. They are: Hazardous Substance Plan; Fire Prevention Plan; and Noxious Weed Management Plan. Lastly, it is noted there are several design review provisions and conditions in the License, and Standard Article 21 in the License will require Chugach to pay for any merchantable sized timber that requires clearing. All slash and debris is to be disposed of according to Chugach National Forest specifications for Stetson Creek project components on Federal Lands. In addition to FERC and Forest Service requirements outlined in the License (including future updates to add Stetson Creek Project components to the existing Special Use Permits administered by the Chugach National Forest), there are several other permits and regulatory approvals necessary to proceed with construction on the Stetson Creek Division Project. If for Stetson Creek Diversion and Cooper Lake Dam Facilities Page 5-2 Feasibility Report – Final 14 March 2011 some reason, it is determined that the Stetson Creek Division Project is not possible or too costly as outlined under Condition 12 of the Settlement Agreement, FERC will require Chugach to file an application to amend its license as specified in Article 401. The permits and regulatory approval requirements are likely to apply are discussed below. 5.1.1 U.S. Army Corps of Engineers 404 Permit The U.S. Army Corps of Engineers (Corps) issues permits under Section 404(a) of the Clean Water Act for the “discharge of dredged or fill” material into “waters of the United States.” The Corps of Engineers issues three types of 404 permits potentially applicable to the construction – general, nationwide, and individual permits. It will be important to contact the Corps prior to submitting a 404 permit application to obtain further guidance on the permit requirements. The Corps will make a determination as to which permit, if any, will be required. The Corps may choose to make a site visit before making this determination. It is expected that an Individual Permit will be required. Based on survey work done in summer 2005 for the Stetson Creek Diversion Project, HDR identified about 4.2 acres of wetlands that would be affected by the project. Activities in wetlands that may result in more than minimal impacts require individual permits. Once a 404 permit application is submitted, the Corps must notify the applicant of any deficiencies in the application within 15 days. After the application is deemed complete, the Corps has 15 days to issue a public notice of the application for posting at governmental offices, facilities near the proposed project site, and other appropriate sites. In the public notice, the Corps will require that comments be submitted within a specified period of time, usually 30 days. The following is a summary of the typical processing procedure for an individual permit: 1. Pre-application consultation (optional, but recommended) 2. Applicant submits ENG Form 4345 to Corps District regulatory office. 3. Application received and assigned identification number. 4. Public notice issued (within 15 days of receiving all information). 5. 15 to 30 day comment period depending upon nature of activity. 6. Proposal reviewed by Corps and: –Public –Special interest groups –Local agencies –State agencies –Federal agencies 7. Corps considers all comments. 8. Other Federal agencies consulted, if appropriate. 9. District engineer may ask applicant to provide additional information. 10. Public hearing held, if needed. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 5-3 Feasibility Report – Final 14 March 2011 11. District engineer makes decision. 12. Permit issued or permit denied and applicant advised of reason. The following information presents more details on the requirements of the application. The application must include a complete description of the proposed activity including necessary drawings, sketches, or plans sufficient for public notice (detailed engineering plans and specifications are not required); the location, purpose and need for the proposed activity; scheduling of the activity; the names and addresses of adjoining property owners; the location and dimensions of adjacent structures; and a list of authorizations required by other federal, interstate, state, or local agencies for the work, including all approvals received or denials already issued. All activities the applicant plans to undertake which are reasonably related to the same project and for which a permit would be required should be included in the same permit application. Since the construction activity would likely include the discharge of dredged or fill material into the waters of the United States (i.e. the wetlands assuming they are found to be jurisdictional); the purpose of the discharge, a description of the type, composition and quantity of the material; the method of transportation and disposal of the material, and the location of the disposal site(s) will all be required. The Corps 404 permit application requires a plan for compensatory mitigation of loss of wetlands. If the construction activity at the dam includes the construction of a filled area or pile or float-supported platform, the project description must include the use of, and specific structures to be erected on, the fill or platform. [Note: Because the construction would involve an impoundment structure, the applicant is required to demonstrate that the structure complies with established FERC dam safety criteria. No specific design criteria are to be prescribed, nor is an independent detailed engineering review to be made by, the Corps District Engineer, as oversight will be undertaken through FERC.] Before issuing a permit under Section 404, the Corps must comply with other environmental laws and regulations. Certification under Section 401 of the Clean Water Act is required for discharges into waters of the United States in Alaska. An Alaska Coastal Management Plan Consistency Determination is also required. Additionally, the Corps must comply with requirements the Endangered Species Act, the National Historic Preservation Act, and NEPA. Under Section 404, the Corps permit may be issued only for the least environmentally damaging practicable alternative. A Cultural Resources Consultants performed a Phase I survey of the proposed pipeline alignment and did not identify any cultural resources within the project area. Concurrence that no historic properties would be affected is required from the State Historic Preservation Office. No threatened or endangered species are expected to be affected by the project; concurrence from the U.S. Fish and Wildlife Service and possibly the National Marine Fisheries Service is required. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 5-4 Feasibility Report – Final 14 March 2011 Under the Magnuson-Fishery Conservation and Management Act, all federal agencies (e.g., Corps of engineers) are required to consult with the National Marine fisheries Service on all actions or proposed actions, permitted, funded, or undertaken by that agency that may adversely affect Essential Fish Habitat (EFH). A determination on effect of the project to EFH will be required by the Corps. That no further action is required under the Alaska National Interest Lands Conservation Act (ANILCA) should be confirmed with the US Forest Service. 5.1.2 401 Water Quality Certification The Alaska Department of Environmental Conservation (ADEC) waived its right to issue a Clean Water Act 401 Water Quality Certification in the relicensing proceeding through FERC (letter of June 1, 2005), but a 401 Certificate is required from ADEC for the Corps of Engineers 404 permit process. The application for the Corps 404 permit to discharge dredged or fill material into waters of the U.S. will also serve as application for the State 401 Water Quality Certification. 5.1.3 Storm Water Pollution Discharge Elimination System Permit (402 Clean Water Act) The U.S. Environmental Protection Agency (EPA) administers the 402 permitting program, for stormwater pollution prevention, with authority delegated to the State of Alaska on a phased schedule. The Alaska Pollutant Discharge Elimination system (APDES) began including stormwater discharge permits as of October 31, 2009. Two general stormwater discharge permits are in effect: one for industrial activities and one for construction activities. The General Permit covering construction under the APDES program is discussed briefly below. Under the EPA’s Construction General Permit (CGP), all developers who plan to disturb 1 or more acres of land surface must submit a Notice of Intent (NOI) to EPA and prepare a Storm Water Pollution Prevention Plan (SWPPP) under direction of the ADEC. The SWPPP is a standard plan prepared for typical large construction projects and ADEC provides instructions on its content and requirements. The SWPPP is one of the last plans needed to be developed as it is not a precursor to the 404 permit or FERC approvals. 5.1.4 Fish Habitat Permit Alternation of stream bank areas and flow with Stetson Creek to construct the pipeline may trigger the requirement for a Fish Habitat Permit from the Alaska Department of Fish and Game (ADF&G), Habitat Division. The ADF&G should be contacted early on to get their determination and input on the need for a fish habitat permit. 5.1.5 Water Rights Chugach has applied to the Alaska Department of Natural Resources (ADNR) for the right to divert flow from Stetson Creek for the purposes of instream flows and electric power generation Stetson Creek Diversion and Cooper Lake Dam Facilities Page 5-5 Feasibility Report – Final 14 March 2011 with a priority application date of April 1, 2005. Chugach will need to follow up with ADNR to fulfill obligations necessary to secure these rights. 5.1.6 Consistency Determination under Alaska Coastal Zone Management Program The State of Alaska uses a coordinated agency review system for processing resource-related permits which are required for proposed projects in or affecting coastal areas of Alaska. This system, called "project consistency review," is based on the federally-approved Alaska Coastal Management Program (ACMP) and is designed to improve management of Alaska's coastal land and water uses. Project proposals are reviewed to determine the project's consistency with the standards of the ACMP and enforceable policies of approved district coastal management programs. In August 2005 Chugach filed a Coastal Project Questionnaire and Certification Statement to the ADNR for the relicensing of the Cooper Creek Project. In both the public notice issued in January 2007, and within the State’s March 8, 2007 Final Consistency Decision, it was noted that a new Coastal Project Questionnaire (CPQ) will need to be submitted for the Stetson Creek Diversion Project. The CPQ helps determine/verify State and Federal permitting requirements as well as which State agency will coordinate the consistency review. The State considers all aspects of a proposed activity in a single consistency review. The answers to the questions must reflect all elements of the activity, and all applications for the entire project must be submitted together. A pre-application meeting among review participants may be useful to identify any concerns, information needs, and to help ensure an expeditious review can take place. A complete application packet includes: A completed, signed CPQ. Copies of required State and/or federal applications, topographic maps and plan drawings required by the approving agency(ies) (Original application materials and associated fees go to the State or federal issuing agency.). Any additional pertinent information, including public notices from agencies. 5.2 PERMITTING TIMELINE All permits for the Stetson Creek Diversion Project should be pursued together on a parallel track. The Corps 404 permitting process is likely the longest and most comprehensive effort but in any case, the permitting periods are expected to take no more than 6 months from time of application filing. The application for the permit can be filed once final drawings (often 60-90 percent complete) are ready. The FERC plans outlined above should be prepared as drafts and circulated to the resource agencies prior to submittal to FERC for approval, at least 6 months prior to construction, if not sooner. If the proposed alignments of the project features as outlined in the 2005 FERC Stetson Creek Diversion and Cooper Lake Dam Facilities Page 5-6 Feasibility Report – Final 14 March 2011 application do not change, no additional field work should be required. However, if they do change, and field work is required, the permitting schedule would likely be delayed. Based on the need for new information, the timing for the preparation of permit packages may not need to be oriented around field seasons. However, it would be prudent to start permitting consultation work immediately to ensure existing surveys will suffice for the Corps process. A key consideration is certainty about project design and facility locations. Any expected changes in location or design should be made prior to spending too much time on permit application packages and agency pre-application efforts. Agencies may also request consideration of design or location alternatives, which could, in turn, require additional field work. Therefore, the recommended approach is prompt agency consultation and screening for potential concerns and/or requirements, followed by completion of application packages and permitting when the proposed project is final. 5.3 COMPLETION TIME EXTENSION Chugach is targeting project completion no later than fall 2015. Chugach will coordinate with all stakeholders including FERC regarding any extensions that may be needed to the project timelines outlined in license documents. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-1 Feasibility Report – Final 14 March 2011 6.0 OPINION OF PROBABLE CONSTRUCTION COST (OPCC) 6.1 BASIS OF ESTIMATE The estimated 2010 construction costs for the two project options, and the 2011 construction cost for the latest Siphon Option design, based on the overall work scope described in Section 3, were prepared on the following basis. The cost estimates in this report are prepared and considered as Association for the Advancement of Cost Engineering (AACE) International Class 4 estimates in accordance with the AACE Cost Estimate Classification System, Recommended Practice No. 18R-97. Estimates with this classification represent a standard level of detail for feasibility level studies with the level of project definition below 15% and have overall accuracy in the range of - 15% to +25%. The following assumptions were made in the development of the cost estimates: 2010 costs are provided in December 2009 dollars (4th quarter 2009). 2011 costs are provided in December 2010 dollars. Escalation to the construction period has not been added. All work will be performed by qualified and experienced construction contractors or major equipment suppliers. All auxiliary equipment and systems are assumed to be supplied by general construction contractor(s). Costs for engineering, Chugach administration, legal costs, environmental studies and permitting are not included in the estimates. It should be noted that costs of labor, materials, competitive bidding environments and procedures, unidentified field conditions, financial and/or market conditions, and other factors likely to affect the OPCC of this project, are and will unavoidably remain in a state of change, especially in light of the high volatility of the market attributable to high demand, low supply, currency fluctuations, Act of Gods and other market events. Therefore, the OPCCs are a "snapshot in time" and the reliability of these OPCCs will degrade over time. No guarantee can be made that bids and project construction costs will not vary significantly from the OPCCs contained herein. 6.2 CONCEPTUAL DESIGN INFORMATION Conceptual design information used to develop the estimated construction costs was obtained from this document. 2010 cost estimates were prepared for both design options that were under consideration in 2010 as described in Section 3. In addition, a 2011 cost estimate was prepared for the current Siphon Option design as depicted in the 2011 Figures. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-2 Feasibility Report – Final 14 March 2011 6.3 ASSUMPTIONS These Estimates were prepared to simulate contractors bidding for a single construction package to be constructed in 2013 and 2014. Contract costs are broken down into Contractor Direct Cost, Contractor Indirect Costs and Contractor Contingency and Margin. 6.4 BASIS OF QUANTITIES The quantities of civil work were based on quantity takeoffs taken from feasibility design drawings as contained herein and other working sketches prepared by MWH. 6.5 BASIS OF PRICING 6.5.1 Resource Rates 6.5.1.1 Labor and Equipment Rates Labor and equipment rates used in the 2010 OPCC were based on current Davis-Bacon guidelines for Alaska (AK2008001, October 23, 2009), as established by the United States Department of Labor. The 2011 OPCC was based on Davis-Bacon guidelines for Alaska (AK00001, December 10, 2010), as established by the same agency. 6.5.1.2 Material Rates Construction material costs are based on current market rates. Costs for HDPE and steel pipe were based on feedback from vendors. 6.5.2 Quantities Current unit for prices for civil work were applied. 6.5.3 Direct Costs Direct costs include: Civil and equipment items have been estimated from first principles, setting up crews and production rates based on previous work. All items are broken down into of labor, construction equipment and material. Permanent electrical and mechanical equipment are included with material. 6.5.4 Contractor and Subcontractor Indirect Costs Contractor and subcontractor indirect costs include: This estimate includes an allowance for labor overtime costs. This allowance is approximately 16% of labor direct cost. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-3 Feasibility Report – Final 14 March 2011 The indirect costs also include an allowance for contractor construction management and supervision, site facilities, site services, quality control and survey. This allowance is approximately 10% of all contractor direct costs. Quality assurance, engineering, contract management and Chugach’s onsite representation are excluded. 6.5.5 Contractor and Subcontractor Margin (Contingency, Overhead & Profit) Contractor markups for subcontracted work, insurance, bonds, and overhead and profit are listed in the OPCC. 6.6 OPCC SUMMARY Summaries of the 2010 OPCC for the Gravity Option and the 2011 OPCC for the Siphon Option are shown in Tables 6-1 and 6-2, respectively. The complete estimate backups are provided in Appendix B. 6.7 OVERALL PROJECT COST Overall project costs have been estimated for the two studied Cooper Creek water release options as shown in Tables 6-3 and 6-4. Owner’s costs as estimated by Chugach include G&A, financing, permitting, internal engineering, right of way and property rights costs. 6.8 COMPARISON OF 2004 EPC AND 2010 OPCC The Opinion of Probable Construction Cost included in this Feasibility Report represents a significant increase over the Estimate of Probable Cost (EPC) completed in the MWH Potential Cooper Creek Protection, Mitigation and Enhancement Measures report (PME Report) dated August 2004, which was based on conceptual information and layouts and with limited site information. The 2004 EPC presented construction estimates for 15 different alternatives to assist Chugach in determining a preferred option for the Stetson Creek Diversion and Cooper Lake Dam Facilities. The following discussion is presented to provide a summary of the primary drivers for the differences in the 2004 EPC and the 2010 OPCC. The comparison is essentially the same for the 2011 OPCC. 6.8.1 Cost Estimation Methodology The following is a summary of the similarities and differences in the methodologies of the 2004 EPC and 2010 OPCC. Estimator: MWH employed the same estimator and lead engineer for both the 2004 EPC and 2010 OPCC. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-4 Feasibility Report – Final 14 March 2011 Table 6-1 2010 Opinion of Probable Construction Cost for Option 1 – Gravity Option Bid Form Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Grand Total Price:17,286,820.00 Total Price: 17,286,820.00 Client Item Client Description Quantity UOM Unit Price Final Price Mobilization 1.00 LS 500,000.00 500,000.00 10 Mobilization 1.00 LS 500,000.00 500,000.00 Main Access Road 1.00 LS 624,960.00 624,960.00 15 Main Access Road 4.50 Mile 138,880.00 624,960.00 Erosion Control & Restoration 1.00 LS 392,700.00 392,700.00 30 Erosion Control 1.00 LS 290,300.00 290,300.00 35 Restoration 20.00 AC 5,120.00 102,400.00 Dam Excavation Backfill 1.00 LS 2,244,240.00 2,244,240.00 40 Dam Excavation & Embankment 1.00 LS 2,000,000.00 2,000,000.00 45 Remove Replace Dam Facing 568.00 CY 430.00 244,240.00 Control Structure 1.00 LS 345,550.00 345,550.00 50 Outlet Tower 179.00 CY 1,430.00 255,970.00 55 Maintenance Building 80.00 SF 320.00 25,600.00 58 Outlet Gates 2.00 EA 31,990.00 63,980.00 Inlet/Outlet Pipe & Outlet 1.00 LS 1,759,180.00 1,759,180.00 60 Outlet 1.00 LS 24,000.00 24,000.00 63 Inlet Outlet Pipe 536.00 LF 3,230.00 1,731,280.00 65 Riprap Outlet 15.00 CY 260.00 3,900.00 Intake 1.00 LS 75,000.00 75,000.00 70 Intake 1.00 LS 75,000.00 75,000.00 Stetson Creek Diversion 1.00 LS 900,000.00 900,000.00 85 Diversion Dam Stetson Creek 1.00 LS 900,000.00 900,000.00 Instrumentation 1.00 LS 268,000.00 268,000.00 86 Instrumentation (Flow Meters & Gauges) 1.00 LS 268,000.00 268,000.00 Stetson Creek Pipeline 1.00 LS 6,719,790.00 6,719,790.00 91 Bridge 1.00 LS 287,000.00 287,000.00 92 Clearing 13.00 AC 6,970.00 90,610.00 95 Pipeline 11,910.00 LF 500.00 5,955,000.00 96 Outlet Pipe in Reservoir 400.00 LF 840.00 336,000.00 97 Energy Dissipation Structure 1.00 LS 51,180.00 51,180.00 99 Contingency 1.00 LS 3,457,400.00 3,457,400.00 Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-5 Feasibility Report – Final 14 March 2011 Table 6-2 2011 Opinion of Probable Construction Cost for Option 2 – Siphon Option Bid Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Grand Total Price: 14,179,451 Total Price 14,179,451 Total Adjustments 0 Total Markup 1,185,905 Markup (%) 11.67 1,185,905 Total Project Cost 10,157,646 Total Construction Cost 12,993,546 Total Indirect Costs (I) 12.78 4,134,413 Total Direct Costs (D) 87.22 8,859,133 ItemSpeod Description Quantity UOM Unit Cost Total Cost DIRECTS SIPHON 1.00 LS 8,859,132.80 8,859,133 Mobilization 1.00 LS 350,000.00 350,000 D 10 Mobilization 1.00 LS 350,000.00 350,000 Main Access Road 1.00 LS 492,612.58 492,613 D 15 Main Access Road 4.50 Mile 109,469.46 492,613 Erosion Control & Restoration 1.00 LS 306,896.70 306,897 D 30 Erosion Control 1.00 LS 226,896.70 226,897 D 35 Restoration 20.00 AC 4,000.00 80,000 Spillway Excavation & Backfill for Pipe 1.00 LS 1,036,695.53 1,036,696 D 40 Spillway Excavation & Embankment 10,850.00 CY 32.04 347,667 D 41 Concrete Cut Off 52.00 CY 208.71 10,853 D 42 Concrete Encase Pipeline 378.00 CY 208.71 78,893 D 42 Concrete Slab Spillway 1,240.00 CY 421.02 522,068 D 43 30 in Bell & Sp Steel Pipe 775.00 LF 99.63 77,214 Inlet/Outlet & Siphon Pipe 1.00 LS 284,391.26 284,391 D 17 Inlet Outlet Channel Excavation 3,800.00 CY 9.06 34,443 D 60 Outlet 1.00 LS 58,304.21 58,304 D 63 Exc Lay Backfill 30in Bell & SP Steel Pipe 725.00 LF 193.77 140,486 D 65 Riprap Outlet 250.00 CY 204.63 51,158 Intake 1.00 LS 77,568.83 77,569 D 70 Intake 1.00 LS 77,568.83 77,569 Stetson Creek Diversion 1.00 LS 778,763.42 778,763 D 85 Diversion Dam Stetson Creek 1.00 LS 778,763.42 778,763 Instrumentation 1.00 LS 210,000.00 210,000 D 86 Instrumentation ( Flow Meters & Guages) 1.00 LS 210,000.00 210,000 Stetson Creek Pipeline 1.00 LS 5,322,204.49 5,322,204 D 92 Clearing 15.00 AC 5,329.69 79,945 D 95 Pipeline 11,910.00 LF 414.78 4,940,004 D 96 Outlet Pipe in Reservoir 400.00 LF 655.64 262,256 D 97 Energy Dissapation Structure 1.00 LS 40,000.00 40,000 INDIRECTS 1.00 LS 1,298,513.00 4,134,413 D 99 Contingency 1.00 LS 2,835,900.00 2,835,900 I 98 Indirects 1.00 LS 1,298,513.00 1,298,513 Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-6 Feasibility Report – Final 14 March 2011 Table 6-3 Estimated Overall Project Cost – Gravity Option (2010) Low Cost ($M) Expected Cost ($M) High Cost ($M) Design Engineering and Construction Management $2.2 $2.6 $3.2 Construction $14.7 $17.3 $21.6 Owner’s Costs $2.2 $2.5 $3.0 TOTAL $19.1 $22.4 $27.8 Table 6-4 Estimated Overall Project Cost – Siphon Option (2011) Low Cost ($M) Expected Cost ($M) High Cost ($M) Design Engineering and Construction Management $2.2 $2.6 $3.2 Construction $12.0 $14.2 $17.7 Owner’s Costs $2.2 $2.5 $3.0 TOTAL $16.4 $19.3 $23.9 Estimate Type: The 2004 EPC is considered an AACE International Class 5 Estimate in accordance with the AACE Cost Estimate Classification System, Recommended Practice No. 18R-97 for design development of 2% or less and accuracy range of –25% and +65%. The 2010 OPCC estimate is a AACE International Class 4 estimate which is applicable for feasibility level studies with the level of project definition below 15% and have overall accuracy in the range of -15% to +25%. Quantities: Material quantities for the 2004 EPC were based on conceptual design, with little engineering being conducted at the time due to the large number of alternatives being investigated. The intent of the 2004 EPC was to differentiate between alternatives. Material quantities for the 2010 OPCC were based on field investigations and feasibility design engineering, providing a significant improvement in quantity estimates and design configuration over the 2004 exercise. Unit Rates: Unit rates for the 2004 EPC were based on typical historic costs for each of the listed construction items in the various alternatives. Conceptual plans provided some input for determining unit rates, however assessments of equipment productivity and crew details were not made due to the preliminary nature of the engineering and layouts. The basis for the 2004 EPC was January 2004 construction costs and was inclusive of contractor mark ups. Unit rates for the 2010 OPCC were calculated using detailed construction crews, materials costs, and productivity estimates based on the feasibility design. The cost of HDPE and steel pipe were also based on local supplier quotes. The basis for the 2010 OPCC was fourth Quarter 2009. Detailed contractor markups were used in the 2010 OPCC. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-7 Feasibility Report – Final 14 March 2011 Contingencies: The total 2004 contingency was 35%, made up of 10% for “Unlisted Items” and 25% for “Construction Contingency”. The 2010 contingency is 25% considering the more detailed basis of the estimate. 6.8.2 Comparison Methodology In order to compare the 2004 EPC and 2010 OPCC, simplifying assumptions were made as follows: The 2004 EPC provided high and low estimates for each construction item. Average values were calculated from these high and low values. These average values were compared to the 2010 OPCC estimate of bid construction costs for like items. Alternative 3d (110 cfs option), that was advanced in March 2005 following submission of the PME Report, was used in this analysis because it has the most similar design requirements and features to the 2010 Gravity Option configuration and used similar estimating procedures. A target total development cost (construction, engineering, construction management and owner’s costs) of $11 million (2004 basis) was indicated in the Settlement Agreement. Alternative 3d with a diversion of 110 cfs had a construction cost range of $8.0 to $10.0 million (2004 basis). In comparison, Alternative 3b (30 cfs option) in the PME Report had a construction cost of $6.1 to $8.4 million (2004 basis). The Gravity Option as defined in the Feasibility Report was considered in this comparison such that similar design configurations were compared. Although the Gravity Option is not the lowest cost option, using it here allows for more accurate analysis of cost estimate evolution. The following major construction groupings were used for the comparison: Mobilization Main Access Road Diversion Pipeline Diversion Dam Cooper Lake Dam Excavation Gravity Structure Electrical and Instrumentation Erosion Control Contingency For comparison, the cost differences in the 2004 EPC and 2010 OPCC were segregated into four categories: impact from construction inflation; impact from construction quantities; impact from design changes and/or estimating assumptions; and not evaluated. Impact from Construction Inflation: A construction cost index (CPI) of 40% was chosen as a reasonable value to index the January 2004 costs to the December 2009 costs, based on the following producer and consumer price indexes reported by the U.S. Bureau of Labor Statistics (www.bls.gov/ppi & www.bls.gov/cpi; 12/03 through 3/09): Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-8 Feasibility Report – Final 14 March 2011 PPI for inputs to highway and street construction: 45.0% PPI for other heavy construction: 37.2% PPI for concrete products: 39.1% PPI for plastic products: 34.7% PPI for steel mill products: 50.1% Impact from Quantities: To determine the impact from design quantities only, the unit rates used in the 2004 EPC were adjusted for inflation and applied to the 2010 quantities for like items. One very large quantity increase was the result of excavation and backfill quantities for placing the outlet pipe through Cooper Lake Dam. Conversations with FERC (summer 2009) prior to initiating the Feasibility Report indicated that they would recommend significantly flatter cut slopes to aid in re-construction of the dam. Impact from design changes and/or assumptions: The impact from changes in design configuration and changes in basic costing assumptions are difficult to separate given the difference in methodology of the two estimates discussed above. This impact item was grouped, and represents the residual impact after accounting for inflation and known quantity impacts. This group includes construction items, material costs, and unit rates that, in the opinion of MWH, should be increased from the 2004 EPC to the 2010 OPCC because further field investigations, engineering and knowledge of the difficulties in constructing facilities in this remote and rugged location, i.e., with further knowledge of the site conditions our opinion of the cost to perform work has changed. Some of these cost impacts include poor access to the diversion dam; need to provide temporary and long-term support for rock cut slopes including rock bolts and wire mesh; difficulty in construction of the diversion pipeline including steep, loose side slopes along Stetson Creek; and added features for diversion pipe and outlet into Cooper Lake due to further engineering hydraulic calculations. Not evaluated: These are items that have a comparatively small value relative to the total construction cost and were not otherwise calculated. 6.8.3 Summary of Cost Impacts Each of these impacts are quantified and summarized below. Appendix E to this document includes the more detailed calculation spreadsheets used to quantify these impacts. Construction Cost 2004 EPC: $6.5M* *Does not include contingency Construction Cost 2010 OPCC: $13.8M* Construction Cost Difference: $7.3M Additional Contingency Difference: $1.1M To classify the impacts to the 2004 and 2010 estimates the following is determined: Impact from CPI: $2.6M (31% of total difference) Impact from quantity increases: $2.6M (31% of total difference) Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-9 Feasibility Report – Final 14 March 2011 Impact from design/assumptions: $2.0M (24% of total difference) Not Evaluated: $0.1M (1% of total difference) Contingency: $1.1M (14% of total difference) Total Impact (increase) $8.4M Major specific impacts (>$0.5M) are summarized below: ITEM IMPACT CATEGORY Pipeline $2.1M Assumptions and/or design configuration Gravity Structure $1.3M Quantities Pipeline $1.3M CPI Dam Excavation $1.2M Quantities Access Road ($0.5M) Assumptions and/or design configuration As indicated above, this evaluation compares similar flow (110 cfs) and similar dam outlets (gravity through the dam) to compare the 2004 EPC and 2010 OPCC. 2010 FIGURES 2011 FIGURES APPENDIX A Geotechnical Feasibility Study – Final Draft Report Appendix A included as a PDF on attached CD. APPENDIX B Opinions of Probable Construction Cost APPENDIX B1 2010 OPCC Gravity Option www.mwhglobal.com Opinion of Probable Construction Cost 13-Jan-10 Class 4 Feasibility TOC:Tab TOC:Tab Detailed Construction Cost Estimate Basis of Estimate Report 1 Subcontractor Summary Report 11 Submitted Date: Jan 2010 Project Summary/Markup Report 2 Schedule 12 Bid Form Report (Off/Balance)3 13 AACE Class: Class 4 Bid Summary 4 14 Accuracy: -15% to +25% Item Summary Report 5 15 Currency: USD Activity Cost Summary Report 6 16 Estimator: DLC Estimate Line Detail Report 7 17 QC: JLL Labor Quantity Report 8 18 Office: SAC Equipment Quantity Report 9 19 Material Quantity Report 10 20 Gravity Option Chugach Electric Association Stetson Creek Diversion and Cooper Lake Dam Facilities Basis of Estimate ReportEstimate: Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency : USD - United States Dollar Date:1/13/2010General Information:Client: Chugach Electric Association Address:Anchorage, AKProject: Stetson Creek Diversion and Cooper Lake Dam Facilities PM:Trey ActesonDescription: Diversion Dam and Pipeline/Dam Outlet Works Phone:907-360-9868Estimate Criteria:AACE Type:Class 4Methodology:Crews & ProductionsDesign:FeasibilityAccuracy Range:-15% TO +25%End Usage:Initial BudgetPrep Effort:n/aReference Documents:1Feasibility Drawings62MWH Designer Takeoff Quantities73 84 95 10Estimate Scope:General Estimate Assumptions:1Pricing basis is 4th quarter of 2009,62Pricing assumes competitive conditions at time of tender (+3 bidders).73 84 95 10Specific Estimate Assumptions:1Work hours = Double shift102Work schedule =6 days/week - Monday through Friday.113Basic design report assumptions124 135 146 157 168 179 18The project consists of the construction of 11900 lineal feet of diversion HDPE pipeline from Stetson Creek to Cooper Dam, to include a diversion structure at Stetson Creek. The project also consists of the construction of an Inlet and outlet structure at Cooper Dam and inlet outlet piping through a gate structure to be excavated within the present dam footprint.Page 1 of 36 Bid Form Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Grand Total Price:17,286,820.00 Total Price: 17,286,820.00 Client Item Client Description Quantity UOM Unit Price Final Price Mobilization 1.00 LS 500,000.00 500,000.00 10 Mobilization 1.00 LS 500,000.00 500,000.00 Main Access Road 1.00 LS 624,960.00 624,960.00 15 Main Access Road 4.50 Mile 138,880.00 624,960.00 Erosion Control & Restoration 1.00 LS 392,700.00 392,700.00 30 Erosion Control 1.00 LS 290,300.00 290,300.00 35 Restoration 20.00 AC 5,120.00 102,400.00 Dam Excavation Backfill 1.00 LS 2,244,240.00 2,244,240.00 40 Dam Excavation & Embankment 1.00 LS 2,000,000.00 2,000,000.00 45 Remove Replace Dam Facing 568.00 CY 430.00 244,240.00 Control Structure 1.00 LS 345,550.00 345,550.00 50 Outlet Tower 179.00 CY 1,430.00 255,970.00 55 Maintenance Building 80.00 SF 320.00 25,600.00 58 Outlet Gates 2.00 EA 31,990.00 63,980.00 Inlet/Outlet Pipe & Outlet 1.00 LS 1,759,180.00 1,759,180.00 60 Outlet 1.00 LS 24,000.00 24,000.00 63 Inlet Outlet Pipe 536.00 LF 3,230.00 1,731,280.00 65 Riprap Outlet 15.00 CY 260.00 3,900.00 Intake 1.00 LS 75,000.00 75,000.00 70 Intake 1.00 LS 75,000.00 75,000.00 Stetson Creek Diversion 1.00 LS 900,000.00 900,000.00 85 Diversion Dam Stetson Creek 1.00 LS 900,000.00 900,000.00 Instrumentation 1.00 LS 268,000.00 268,000.00 86 Instrumentation (Flow Meters & Gauges) 1.00 LS 268,000.00 268,000.00 Stetson Creek Pipeline 1.00 LS 6,719,790.00 6,719,790.00 91 Bridge 1.00 LS 287,000.00 287,000.00 92 Clearing 13.00 AC 6,970.00 90,610.00 95 Pipeline 11,910.00 LF 500.00 5,955,000.00 96 Outlet Pipe in Reservoir 400.00 LF 840.00 336,000.00 97 Energy Dissipation Structure 1.00 LS 51,180.00 51,180.00 99 Contingency 1.00 LS 3,457,400.00 3,457,400.00 Page 2 of 36 Bid Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Grand Total Price: 17,286,668 Total Price 17,286,668 Total Adjustments 0 Total Markup 1,455,191 Markup (%) 11.76 1,455,191 Total Project Cost 15,831,477 Total Construction Cost 15,831,477 Total Indirect Costs (I) 32% 5,023,107 Total Direct Costs (D) 68% 10,808,370 Item Cod Description Quantity UOM Unit Cost Total Cost DIRECTS 1.00 LS 10,808,368.88 10,808,369 Mobilization 1.00 LS 350,000.00 350,000 D 10 Mobilization 1.00 LS 350,000.00 350,000 Main Access Road 1.00 LS 488,457.12 488,457 D 15 Main Access Road 4.50 Mile 108,546.03 488,457 Erosion Control & Restoration 1.00 LS 306,777.46 306,777 D 30 Erosion Control 1.00 LS 226,777.46 226,777 D 35 Restoration 20.00 AC 4,000.00 80,000 Dam Excavation Backfill 1.00 LS 1,790,489.25 1,790,489 D 40 Dam Excavation & Embankment 1.00 LS 1,600,125.20 1,600,125 D 45 Remove Replace Dam Facing 568.00 CY 335.15 190,364 Control Structure 1.00 LS 270,541.59 270,542 D 50 Outlet Tower 179.00 CY 1,120.34 200,542 D 55 Maintenance Building 80.00 SF 250.00 20,000 D 58 Outlet Gates 2.00 EA 25,000.00 50,000 Inlet/Outlet Pipe & Outlet 1.00 LS 1,374,208.49 1,374,208 D 60 Outlet 1.00 LS 19,463.20 19,463 D 63 Inlet Outlet Pipe 536.00 LF 2,521.79 1,351,680 D 65 Riprap Outlet 15.00 CY 204.38 3,066 Intake 1.00 LS 58,486.95 58,487 D 70 Intake 1.00 LS 58,486.95 58,487 Stetson Creek Diversion 1.00 LS 704,845.10 704,845 D 85 Diversion Dam Stetson Creek 1.00 LS 704,845.10 704,845 Instrumentation 1.00 LS 210,000.00 210,000 D 86 Instrumentation (Flow Meters & Gauges) 1.00 LS 210,000.00 210,000 Stetson Creek Pipeline 1.00 LS 5,254,562.90 5,254,563 D 91 Bridge 1.00 LS 225,000.00 225,000 D 92 Clearing 13.00 AC 5,446.19 70,800 D 95 Pipeline 11,910.00 LF 390.96 4,656,314 D 96 Outlet Pipe in Reservoir 400.00 LF 656.12 262,449 D 97 Energy Dissipation Structure 1.00 LS 40,000.00 40,000 INDIRECTS 1.00 LS 5,023,107.00 5,023,107 D 99 Contingency 1.00 LS 3,457,400.00 3,457,400 I 98 Indirects 1.00 LS 1,565,707.00 1,565,707 Page 3 of 36 Item Cost SummaryStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItem Description QuantityUOM ManHr LaborEquip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total CostDIRECTSMobilization10 Mobilization1.00LS 350,000 350,000350,000.00 350,000.00Section Totals:1.00LS 0 0 0 350,000 350,0000.00 0.00 0.00 0.00 0.00 0.00 350,000.00 350,000.00Main Access Road15 Main Access Road4.50Mile 2,271 146,675 67,032 254,750 20,000 488,457504.67 32,594.42 14,896.05 56,611.11 4,444.44 108,546.03Section Totals:1.00LS 2,271 146,675 67,032 254,750 20,000 488,4572,271.03 146,674.91 67,032.21 0.00 254,750.00 0.00 20,000.00 488,457.12Erosion Control & Restoration30 Erosion Control1.00LS 1,574 103,143 54,045 69,590 226,7771,574.15 103,142.55 54,044.91 69,590.00 226,777.4635 Restoration20.00AC 80,000 80,0004,000.00 4,000.00Section Totals:1.00LS 1,574 103,143 54,045 69,590 80,000 306,7771,574.15 103,142.55 54,044.91 69,590.00 0.00 0.00 80,000.00 306,777.46Dam Excavation Backfill40 Dam Excavation & Embankment1.00LS 10,110 705,283 699,693 195,150 1,600,12510,110.49 705,282.65 699,692.55 195,150.00 1,600,125.2045 Remove Replace Dam Facing568.00CY 834 51,908 13,035 125,421 190,3641.47 91.39 22.95 220.81 335.15Section Totals:1.00LS 10,944 757,190 712,728 320,571 0 1,790,48910,944.09 757,190.49 712,727.76 0.00 320,571.00 0.00 0.00 1,790,489.25Control Structure50 Outlet Tower179.00CY 1,339 86,411 6,381 7,116 100,633 200,5427.48 482.74 35.65 39.75 562.20 1,120.3455 Maintenance Building80.00SF 20,000 20,000250.00 250.0058 Outlet Gates2.00EA 50,000 50,00025,000.00 25,000.00Section Totals:1.00LS 1,339 86,411 6,381 7,116 100,633 70,000 270,5421,339.44 86,411.16 6,381.13 7,116.00 100,633.30 0.00 70,000.00 270,541.59Page 4 of 36 Item Cost SummaryStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItem Description QuantityUOM ManHr LaborEquip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total CostInlet/Outlet Pipe & Outlet60 Outlet1.00LS 146 9,425 540 3,564 5,935 19,463146.04 9,424.75 539.84 3,564.00 5,934.61 19,463.2063 Inlet Outlet Pipe536.00LF 8,629 594,194 519,869 8,545 226,372 2,700 1,351,68016.10 1,108.57 969.90 15.94 422.34 5.04 2,521.7965 Riprap Outlet15.00CY 15 990 506 1,570 3,0661.00 65.97 33.74 104.67 204.38Section Totals:1.00LS 8,790 604,608 520,915 12,109 233,876 2,700 1,374,2088,789.76 604,608.28 520,914.81 12,109.00 233,876.40 0.00 2,700.00 1,374,208.49Intake70 Intake1.00LS 159 10,240 610 2,323 10,313 35,000 58,487158.70 10,240.05 610.45 2,323.17 10,313.29 35,000.00 58,486.95Section Totals:1.00LS 159 10,240 610 2,323 10,313 35,000 58,487158.70 10,240.05 610.45 2,323.17 10,313.29 0.00 35,000.00 58,486.95Stetson Creek Diversion85 Diversion Dam Stetson Creek1.00LS 3,956 256,027 24,067 56,177 249,042 119,532 704,8453,956.31 256,027.19 24,067.06 56,177.14 249,041.73 119,532.00 704,845.10Section Totals:1.00LS 3,956 256,027 24,067 56,177 249,042 119,532 704,8453,956.31 256,027.19 24,067.06 56,177.14 249,041.73 0.00 119,532.00 704,845.10Instrumentation86 Instrumentation (Floe Meters & Gauges)1.00LS 210,000 210,000210,000.00 210,000.00Section Totals:1.00LS 0 0 0 210,000 210,0000.00 0.00 0.00 0.00 0.00 0.00 210,000.00 210,000.00Stetson Creek Pipeline91 Bridge1.00LS 225,000 225,000225,000.00 225,000.0092 Clearing13.00AC 905 58,022 12,779 70,80069.61 4,463.20 982.98 5,446.1995 Pipeline11,910.00LF 15,308 957,711 546,198 54,173 2,958,232 140,000 4,656,3141.29 80.41 45.86 4.55 248.38 11.75 390.9696 Outlet Pipe in Reservoir400.00LF 724 50,333 34,616 63,500 50,000 20,000 44,000 262,4491.81 125.83 86.54 158.75 125.00 50.00 110.00 656.1297 Energy Dissipation Structure1.00LS 40,000 40,00040,000.00 40,000.00Section Totals:1.00LS 16,937 1,066,065 593,592 117,673 3,008,232 20,000 449,000 5,254,56316,937.23 1,066,065.33 593,592.28 117,672.80 3,008,232.49 20,000.00 449,000.00 5,254,562.90Section Totals:1.00LS 45,971 3,030,360 1,979,371 264,988 4,177,418 20,000 1,336,232 10,808,36945,970.71 3,030,359.96 1,979,370.61 264,988.10 4,177,418.21 20,000.00 1,336,232.00 10,808,368.88INDIRECTS98 Indirects1.00LS 1 484,857 1,080,850 1,565,7071.00 484,857.00 1,080,850.00 1,565,707.0099 Contingency1.00LS 3,457,400 3,457,4003,457,400.00 3,457,400.00Section Totals:1.00LS 1 484,857 0 4,538,250 5,023,1071.00 484,857.00 0.00 0.00 0.00 0.00 4,538,250.00 5,023,107.00Grand Totals:1.00LS 45,972 3,515,217 1,979,371 264,988 4,177,418 20,000 5,874,482 15,831,4763,515,216.96 1,979,370.61 264,988.10 4,177,418.21 20,000.00 5,874,482.0015,831,475.88Page 5 of 36 Activity Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Total: 15,831,475.88 Item Description Quantity UOM Unit Cost Total Cost DIRECTS 1.00 LS 0.00 10,808,368.88 Mobilization 1.00 LS 0.00 350,000.00 10 B Mobilization 1.00 LS 350,000.00 350,000.00 10 B Mobilization 1.00 LS 350,000.00 350,000.00 Main Access Road 1.00 LS 0.00 488,457.12 15 B Main Access Road 4.50 Mile 108,546.03 488,457.12 10 B Main Access Road Clearing 3.30 AC 2,115.65 6,981.65 15 B Access Road Grading 42,240.00 SY 1.73 73,078.02 20 B Access Road Drainage 2,000.00 LF 95.89 191,778.33 25 B Access Road Gravel Surfacing 3,615.00 CY 54.39 196,619.13 30 B Access Road Stream Crossings 2.00 EA 10,000.00 20,000.00 Erosion Control & Restoration 1.00 LS 0.00 306,777.46 30 B Erosion Control 1.00 LS 226,777.46 226,777.46 35 B Restoration 20.00 AC 4,000.00 80,000.00 Dam Excavation Backfill 1.00 LS 0.00 1,790,489.25 40 B Dam Excavation & Embankment 1.00 LS 1,600,125.20 1,600,125.20 10 B Dam Excavation 69,155.00 CY 9.05 626,083.27 15 B Dam Embankment 65,252.00 CY 11.39 743,250.73 25 B Dam Embankment Drainage Blanket 3,903.00 CY 59.13 230,791.20 45 B Remove Replace Dam Facing 568.00 CY 335.15 190,364.06 10 B Remove Facing 568.00 CY 19.94 11,327.06 20 B Replace Fabform & Concrete Face 568.00 CY 315.21 179,037.00 Control Structure 1.00 LS 0.00 270,541.59 50 B Outlet Tower 179.00 CY 1,120.34 200,541.59 10 B Tower Concrete 179.00 CY 1,120.34 200,541.59 10 B Tower Concrete 179.00 CY 1,120.34 200,541.59 10 B Foundation Prep 225.00 SF 4.75 1,068.93 15 B Build Base Slab Forms 240.00 SF 14.88 3,571.58 20 B SSM Base Slab Forms 240.00 SF 18.15 4,356.08 25 B Place Concrete Base Slab 34.00 CY 208.75 7,097.53 30 B Finish Concrete Base Slab 225.00 SF 0.52 116.30 35 B Cure Concrete Base Slab 465.00 SF 0.29 134.25 40 B Build Wall Forms 750.00 SF 63.77 47,825.47 45 B SSM Wall Forms 5,100.00 SF 9.23 47,086.50 46 B Waterstop at Walls 134.25 LF 12.82 1,720.64 50 B Joint Prep on Slab 215.00 SF 0.83 178.54 55 B Place Concrete Wall 140.00 CY 208.79 29,230.64 60 B Finish Concrete Wall 215.00 SF 0.42 91.00 65 B Cure Concrete Wall 5,315.00 SF 0.41 2,177.29 70 B Patch & Point Walls 5,100.00 SF 0.43 2,210.90 75 B Build Roof Forms 257.76 SF 28.50 7,345.60 80 B SSM Roof Forms 257.76 SF 15.41 3,972.33 85 B Place Roof Concrete 5.00 CY 211.40 1,057.01 90 B Finish Roof Concrete 44.75 SF 0.88 39.60 95 B Cure Roof Concrete 229.12 SF 0.31 70.95 96 B Patch & Point Roof 114.56 SF 0.43 49.66 98 B Reinforcement 35,800.00 LB 1.15 41,140.80 55 B Maintenance Building 80.00 SF 250.00 20,000.00 10 B Maintenance Building 80.00 SF 250.00 20,000.00 58 B Outlet Gates 2.00 EA 25,000.00 50,000.00 Inlet/Outlet Pipe & Outlet 1.00 LS 0.00 1,374,208.49 Page 6 of 36 Activity Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Total: 15,831,475.88 Item Description Quantity UOM Unit Cost Total Cost 60 B Outlet 1.00 LS 19,463.20 19,463.20 10 B Outlet Structure Concrete 16.00 CY 1,216.45 19,463.20 10 B Outlet Concrete 16.00 CY 1,216.45 19,463.20 10 B Foundation Prep 154.00 SF 0.25 38.11 15 B Build Base Slab Forms 50.00 SF 14.88 744.08 20 B SSM Base Slab Forms 50.00 SF 18.15 907.52 25 B Place Concrete Base Slab 6.00 CY 208.75 1,252.50 30 B Finish Concrete Base Slab 154.00 SF 0.52 79.60 35 B Cure Concrete Base Slab 204.00 SF 0.29 58.90 40 B Build Wall Forms 200.00 SF 28.21 5,641.46 45 B SSM Wall Forms 400.00 SF 9.23 3,693.06 50 B Joint Prep on Slab 50.00 SF 0.83 41.52 55 B Place Concrete Wall 10.00 CY 208.79 2,087.90 60 B Finish Concrete Wall 50.00 SF 0.42 21.16 65 B Cure Concrete Wall 450.00 SF 0.31 139.34 70 B Patch & Point Walls 400.00 SF 0.43 173.40 75 B Reinforcement 3,989.47 LB 1.15 4,584.64 63 B Inlet Outlet Pipe 536.00 LF 2,521.79 1,351,679.65 15 B Inlet Outlet Pipe Lay Steel Pipe 536.00 LF 454.02 243,357.19 17 B Inlet /Outlet Backfill 29,964.00 CY 11.39 341,303.94 18 B Inlet Outlet Pipe Excavation 74,412.00 CY 9.09 676,264.81 20 B Concrete Encase Outlet Pipe 93.00 CY 975.85 90,753.70 10 B Concrete Encase Pipe 250LF 93.00 CY 975.85 90,753.70 10 B Foundation Prep 1,250.00 SF 0.25 309.30 15 B Build Wall Forms 1,000.00 SF 18.20 18,197.29 20 B SSM Wall Forms 2,600.00 SF 9.23 24,004.88 25 B Place Concrete 93.00 CY 208.79 19,417.49 30 B Finish Concrete 1,250.00 SF 0.42 529.05 35 B Cure Concrete Wall 3,850.00 SF 0.41 1,577.15 40 B Reinforcement 23,250.00 LB 1.15 26,718.54 65 B Riprap Outlet 15.00 CY 204.38 3,065.65 10 B Place Riprap & Bedding 15.00 CY 204.38 3,065.65 Intake 1.00 LS 0.00 58,486.95 70 B Intake 1.00 LS 58,486.95 58,486.95 10 B Intake Concrete 31.00 CY 757.64 23,486.95 10 B Intake Concrete 31.00 CY 757.64 23,486.95 10 B Foundation Prep 140.48 SF 0.25 34.76 15 B Build Base Slab Forms 28.31 SF 4.97 140.83 20 B SSM Base Slab Forms 28.31 SF 17.15 485.49 25 B Place Concrete Base Slab 10.44 CY 208.75 2,179.80 30 B Finish Concrete Base Slab 140.48 SF 0.52 72.61 35 B Cure Concrete Base Slab 168.79 SF 0.29 48.73 40 B Build Wall Forms 447.71 SF 9.40 4,208.75 45 B SSM Wall Forms 447.71 SF 8.23 3,685.80 50 B Joint Prep on Slab 27.00 SF 0.83 22.42 55 B Place Concrete Wall 16.15 CY 208.79 3,372.51 60 B Finish Concrete Wall 27.00 SF 0.42 11.43 65 B Cure Concrete Wall 474.71 SF 0.31 146.99 70 B Patch & Point Walls 447.71 SF 0.43 194.08 75 B Reinforcement 7,729.61 LB 1.15 8,882.74 20 B Trashrack & Stoplogs 1.00 EA 35,000.00 35,000.00 Stetson Creek Diversion 1.00 LS 0.00 704,845.10 Page 7 of 36 Activity Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Total: 15,831,475.88 Item Description Quantity UOM Unit Cost Total Cost 85 B Diversion Dam Stetson Creek 1.00 LS 704,845.10 704,845.10 10 B Clearing 0.30 AC 25,025.83 7,507.75 12 B Stetson Creek Structure Excavation 1,008.00 CY 24.46 24,651.53 15 B Concrete Stetson Creek Diversion Structure 719.00 CY 763.21 548,747.08 10 B Diversion structure Concrete 719.00 CY 763.21 548,747.08 10 B Foundation Prep 3,258.21 SF 0.25 806.20 15 B Build Base Slab Forms 656.56 SF 4.97 3,266.28 20 B SSM Base Slab Forms 656.56 SF 17.15 11,260.22 25 B Place Concrete Base Slab 242.19 CY 208.75 50,557.24 30 B Finish Concrete Base Slab 3,258.21 SF 0.52 1,684.14 35 B Cure Concrete Base Slab 3,914.77 SF 0.29 1,130.26 40 B Build Wall Forms 10,383.87 SF 9.40 97,615.86 45 B SSM Wall Forms 10,383.87 SF 8.23 85,486.76 50 B Joint Prep on Slab 626.29 SF 0.83 520.09 55 B Place Concrete Wall 374.64 CY 208.79 78,220.53 60 B Finish Concrete Wall 626.29 SF 0.42 265.07 65 B Cure Concrete Wall 11,010.16 SF 0.31 3,409.30 70 B Patch & Point Walls 10,383.87 SF 0.43 4,501.51 75 B Reinforcement 179,276.97 LB 1.15 206,022.30 80 B Waterstop at Walls 312.20 LF 12.82 4,001.33 20 B Diversion Structure Mechanical 1.00 LS 123,938.74 123,938.74 10 B 48in Sluice Gate 1.00 EA 50,000.00 50,000.00 15 B 36in Sluice Gate 1.00 EA 36,000.00 36,000.00 20 B Trashrack 28 x 28 1.00 EA 25,000.00 25,000.00 21 B Safety Railing 60.00 LF 81.65 4,898.85 22 B Grating 264.00 SF 30.45 8,039.89 Instrumentation 1.00 LS 0.00 210,000.00 86 B Instrumentation (Floe Meters & Gauges) 1.00 LS 210,000.00 210,000.00 Stetson Creek Pipeline 1.00 LS 0.00 5,254,562.90 91 B Bridge 1.00 LS 225,000.00 225,000.00 10 B Bridge 1.00 LS 225,000.00 225,000.00 92 B Clearing 13.00 AC 5,446.19 70,800.41 10 B Clearing 13.00 AC 5,446.19 70,800.41 95 B Pipeline 11,910.00 LF 390.96 4,656,313.61 10 B Pipeline Common Excavation 16,120.00 CY 8.01 129,101.64 15 B Pipeline Rock Excavation 13,680.00 CY 25.48 348,508.79 10 B Drill & Shoot 13,680.00 CY 11.23 153,688.62 15 B Excavate Rock 13,680.00 CY 14.24 194,820.16 16 B Culvert Pipe 500.00 LF 114.35 57,173.63 17 B Rock Anchors 2,440.00 LF 34.47 84,098.14 10 B Rock Bolts 2,440.00 LF 34.47 84,098.14 18 B Wire Mesh 21,200.00 SF 2.99 63,423.45 19 B Pipeline Exc & Lay HDPE Pipe 42in 11,910.00 LF 239.31 2,850,186.97 20 B Pipeline Bedding 1,450.00 CY 76.12 110,375.74 25 B Pipeline Select Backfill 1.5 in Minus 10,184.00 CY 76.12 775,218.30 30 B Pipeline Backfill Common 13,925.00 CY 7.05 98,226.95 40 B Gabion Walls 4,000.00 SF 35.00 140,000.00 96 B Outlet Pipe in Reservoir 400.00 LF 656.12 262,448.88 10 B Freight In & Out Fexifloats 18.00 LDS 3,000.00 54,000.00 30 B Assemble Dock & Crane Barge 1.00 LS 35,128.48 35,128.48 31 B Mobilize Crane 1.00 LS 6,000.00 6,000.00 40 B Pipeline HDPE Pipe 36in Fuse Pipe 400.00 LF 153.57 61,429.20 45 B Set & Anchor Pipe to Lake Bottom 400.00 LF 264.73 105,891.20 97 B Energy Dissipation Structure 1.00 LS 40,000.00 40,000.00 INDIRECTS 1.00 LS 0.00 5,023,107.00 98 B Indirects 1.00 LS 1,565,707.00 1,565,707.00 10 A Indirects 1.00 LS 1,080,850.00 1,080,850.00 20 B Labor Overtime 1.00 LS 484,857.00 484,857.00 99 A Contingency 1.00 LS 3,457,400.00 3,457,400.00 Page 8 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total CostDIRECTS 1.00 LS 45,971 3,030,360 1,979,371 264,988 4,177,418 20,000 1,336,232 10,808,36945,970.71 3,030,359.96 1,979,370.61 264,988.10 4,177,418.21 20,000.00 1,336,232.00 10,808,368.88Mobilization 1.00 LS 350,000 350,000350,000.00 350,000.0010 Mobilization 1.00 LS 350,000 350,000350,000.00 350,000.0010 Mobilization 1.00 LS 350,000 350,000350,000.00 350,000.00Mobilization 1.0 LS 350,000.00 350,000Main Access Road 1.00 LS 2,271 146,675 67,032 254,750 20,000 488,4572,271.03 146,674.91 67,032.21 254,750.00 20,000.00 488,457.1215 Main Access Road 4.50 Mile 2,271 146,675 67,032 254,750 20,000 488,457504.67 32,594.42 14,896.05 56,611.11 4,444.44 108,546.0310 Main Access Road Clearing 3.30 AC 89 5,677 1,305 6,98227.00 1,720.26 395.39 2,115.65Prod=1.00 AC/hour, 27.000MH/AC, 0.04 AC/MH, 3.30 hourClear Right of Way 1.00 EA 2115.65Pusher 1.0 75.00 248General Laborer 20.0 61.41 4,053Equipment Foreman 1.0 75.00 248Backhoe Operator 1.0 73.56 243Dozer Operator 1.0 70.88 234Truck Driver 2.0 63.37 418Oiler 1.0 70.88 234305 Hsp Bulldozer ( Cat D8 ) 1.0 136.76 4512.6 CY Backhoe (Cat 350) 1.0 98.70 32620 Ton (10 CY) Tandem Truck 1.0 38.17 12610 Ton All Terrain Vehicle ( Nodwell 110 ) 1.0 81.61 2693/4 Ton Pickup Truck 2x2 1.0 11.14 373/4 Ton Crew Cab Truck 1.0 11.34 375 Ton Flat Bed Truck 1.0 17.67 5815 Access Road Grading 42,240.00 SY 704 47,831 25,247 73,0780.02 1.13 0.60 1.73Prod=300.00 SY/hour, 0.017MH/SY, 60.00 SY/MH, 140.80 hourGrading Access 1.00 EA 519.02Foreman 1.0 71.37 10,049Equip Oper Cl 3 (Grader) 1.0 70.88 9,980Equip Oper Cl 4 (Roller) 1.0 70.88 9,980Equip Oper Cl 4 (Gradechecker) 1.0 70.88 9,980Truck Driver Cl 4 (Water) 1.0 55.70 7,843200 Hsp Grader (Cat 14G) 1.0 87.75 12,35515 Ton Compactor 84" (Cat 563) 1.0 47.13 6,6363/4 Ton Pickup Truck 2x2 1.0 11.14 1,5695000 Gallon Watertanker 1.0 33.29 4,68720 Access Road Drainage 2,000.00 LF 1,333 83,272 34,507 74,000 191,7780.67 41.64 17.25 37.00 95.89Prod=12.00 LF/hour, 0.667MH/LF, 1.50 LF/MH, 166.67 hourExc Lay Backfill Pipe 1.00 EA 706.67Foreman 1.0 71.37 11,895Equip Oper Cl 3 (Backhoe) 1.0 73.56 12,260Equip Oper Cl 3 (Loader) 1.0 70.88 11,813Labor Cl 5 (Pipe) 4.0 57.03 38,020Truck Driver Cl 4 (Water) 1.0 55.70 9,2833.5 CY Loader (Cat 950) 1.0 58.84 9,8072.6 CY Backhoe (Cat 350) 1.0 98.70 16,450Jumping Jack Handheld Packer 1.0 4.12 68724" Smooth Drum Manual (Bomag 60) 1.0 6.41 1,0683/4 Ton Pickup Truck 2x2 1.0 11.14 1,8573000 Gallon Watertruck 1.0 27.83 4,638Access Road Pipe 2,000.0 LF 37.00 74,000Page 9 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost25 Access Road Gravel Surfacing 3,615.00 CY 145 9,895 5,974 180,750 196,6190.04 2.74 1.65 50.00 54.39Prod=150.00 CY/hour, 0.040MH/CY, 25.00 CY/MH, 24.10 hourPlace Compact Grade Road Base Gravel 1.00 EA 658.47Foreman 1.0 71.37 1,720Equip Oper Cl 3 (Grader) 1.0 70.88 1,708Equip Oper Cl 3 (Dozer) 1.0 70.88 1,708Equip Oper Cl 4 (Roller) 1.0 70.88 1,708Equip Oper Cl 4 (Gradechecker) 1.0 70.88 1,708Truck Driver Cl 4 (Water) 1.0 55.70 1,342170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 1,653200 Hsp Grader (Cat 14G) 1.0 87.75 2,11515 Ton Compactor 84" (Cat 563) 1.0 47.13 1,1363/4 Ton Pickup Truck 2x2 1.0 11.14 2685000 Gallon Watertanker 1.0 33.29 802Road Base Gravel 3,615.0 CY 50.00 180,75030 Access Road Stream Crossings 2.00 EA 20,000 20,00010,000.00 10,000.00Stream Crossings 2.0 EA 10,000.00 20,000Erosion Control & Restoration 1.00 LS 1,574 103,143 54,045 69,590 80,000 306,7771,574.15 103,142.55 54,044.91 69,590.00 80,000.00 306,777.4630 Erosion Control 1.00 LS 1,574 103,143 54,045 69,590 226,7771,574.15 103,142.55 54,044.91 69,590.00 226,777.46Prod=196.85 FT/hour, 0.020MH/FT, 49.21 FT/MH, 152.40 hourErect Silt Fence with Rubber Tire Backhoe 1.00 EA 303.07Foreman Roadwork 1.0 71.11 10,837Laborer Roadwork 2.0 57.03 17,383Backhoe Operator 1.0 73.56 11,2111.7 CY Backhoe Loader (Case680) 1.0 35.51 5,4121/2 Ton Pickup Truck 2x2 1.0 8.83 1,346Prod=10.00 EA/hour, 0.400MH/EA, 2.50 EA/MH, 50.00 hourPlace Straw Bales 1.00 EA 303.07Foreman Roadwork 1.0 71.11 3,556Laborer Roadwork 2.0 57.03 5,703Backhoe Operator 1.0 73.56 3,6781.7 CY Backhoe Loader (Case680) 1.0 35.51 1,7761/2 Ton Pickup Truck 2x2 1.0 8.83 442Prod=6.54 CY/hour, 0.382MH/CY, 2.62 CY/MH, 305.82 hourPlace Rock Protection 1.00 EA 313.405Skilled Laborer Roadwork 1.0 57.03 17,441Backhoe Operator 1.0 73.56 22,496Loader Operator 0.5 70.88 10,8382.0 CY Loader (CAT IT28) 0.5 38.33 5,8612.0 CY Backhoe ( Cat 330 ) 1.0 80.43 24,59720 Ton (10 CY) Tandem Truck-Operated 1.0 47.78 14,6129" Riprap (250mm) 4,000.0 TN 12.65 50,600Heavy Duty Silt Fence 30,000.0 FT 0.55 16,500Straw Bales 500.0 EA 3.98 1,990Stakes for Straw Bales (2" x 2" x 4 ft) 500.0 EA 1.00 50035 Restoration 20.00 AC 80,000 80,0004,000.00 4,000.00Seeding & Wood Fiber Mulch 20.0 AC 4,000.00 80,000Dam Excavation Backfill 1.00 LS 10,944 757,190 712,728 320,571 1,790,48910,944.09 757,190.49 712,727.76 320,571.00 1,790,489.25Page 10 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost40 Dam Excavation & Embankment 1.00 LS 10,110 705,283 699,693 195,150 1,600,12510,110.49 705,282.65 699,692.55 195,150.00 1,600,125.2010 Dam Excavation 69,155.00 CY 4,610 321,243 304,840 626,0830.07 4.65 4.41 9.05Prod=150.00 CY/hour, 0.067MH/CY, 15.00 CY/MH, 461.03 hourExcavation Crew 1.00 EA 1358Foreman 1.0 71.37 32,904Equip Oper Cl 3 (Backhoe) 1.0 73.56 33,914Equip Oper Cl 3 (Grader) 1.0 70.88 32,678Equip Oper Cl 3 (Dozer) 1.0 70.88 32,678Equip Oper Cl 7 Art truck 4.0 70.88 130,712Equip Oper Cl 6 Gradechecker 1.0 70.88 32,678Truck Driver Cl 4 (Water) 1.0 55.70 25,680170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 31,613200 Hsp Grader (Cat 14G) 1.0 87.75 40,4562.6 CY Backhoe (Cat 350) 1.0 98.70 45,50430 Ton Articulated Truck (Cat D300) 4.0 90.44 166,7833/4 Ton Pickup Truck 2x2 1.0 11.14 5,1365000 Gallon Watertanker 1.0 33.29 15,34815 Dam Embankment 65,252.00 CY 5,220 364,780 378,470 743,2510.08 5.59 5.80 11.39Prod=150.00 CY/hour, 0.080MH/CY, 12.50 CY/MH, 435.01 hourHaul Place Backfill Crew 1.00 EA 1708.57Foreman 1.0 71.37 31,047Equip Oper Cl 3 (Dozer) 2.0 70.88 61,667Equip Oper Cl 3 Grader) 1.0 70.88 30,834Equip Oper Cl 3 (Backhoe) 1.0 73.56 32,000Equip Oper Cl 4 (Roller) 1.0 70.88 30,834Equip Oper Cl 7 Art truck 4.0 70.88 123,335Equip Oper Cl 6 Gradechecker 1.0 70.88 30,834Truck Driver Cl 4 (Water) 1.0 55.70 24,230170 Hsp Bulldozer ( Cat D6 ) 2.0 68.57 59,658200 Hsp Grader (Cat 14G) 1.0 87.75 38,1722.6 CY Backhoe (Cat 350) 1.0 98.70 42,93630 Ton Articulated Truck (Cat D300) 4.0 90.44 157,37030 Ton Compactor 315 hsp (Cat 825) 1.0 140.24 61,0063/4 Ton Pickup Truck 2x2 1.0 11.14 4,8465000 Gallon Watertanker 1.0 33.29 14,48225 Dam Embankment Drainage Blanket 3,903.00 CY 280 19,259 16,382 195,150 230,7910.07 4.93 4.20 50.00 59.13Prod=97.58 CY/hour, 0.072MH/CY, 13.94 CY/MH, 40.00 hourExcavation Crew 1.00 EA 891.03Foreman 1.0 71.37 2,855Equip Oper Cl 3 (Dozer) 2.0 70.88 5,670Equip Oper Cl 3 Grader) 1.0 70.88 2,835Equip Oper Cl 4 (Roller) 1.0 70.88 2,835Equip Oper Cl 6 Gradechecker 1.0 70.88 2,835Truck Driver Cl 4 (Water) 1.0 55.70 2,228170 Hsp Bulldozer ( Cat D6 ) 2.0 68.57 5,486200 Hsp Grader (Cat 14G) 1.0 87.75 3,51030 Ton Compactor 315 hsp (Cat 825) 1.0 140.24 5,6103/4 Ton Pickup Truck 2x2 1.0 11.14 4465000 Gallon Watertanker 1.0 33.29 1,332Dam Embankment Drainage Blanket 3,903.0 CY 50.00 195,150Page 11 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost45 Remove Replace Dam Facing 568.00 CY 834 51,908 13,035 125,421 190,3641.47 91.39 22.95 220.81 335.1510 Remove Facing 568.00 CY 114 7,495 3,832 11,3270.20 13.19 6.75 19.94Prod=25.00 CY/hour, 0.200MH/CY, 5.00 CY/MH, 22.72 hourRemove facing 1.00 EA 498.55Foreman 1.0 71.37 1,622Equip Oper Cl 3 (Backhoe) 1.0 73.56 1,671Equip Oper Cl 3 (Loader) 1.0 70.88 1,610Labor Cl 5 (Pipe) 2.0 57.03 2,5913.5 CY Loader (Cat 950) 1.0 58.84 1,3372.6 CY Backhoe (Cat 350) 1.0 98.70 2,2423/4 Ton Pickup Truck 2x2 1.0 11.14 25320 Replace Fabform & Concrete Face 568.00 CY 720 44,413 9,203 125,421 179,0371.27 78.19 16.20 220.81 315.21Prod=4.73 CY/hour, 1.268MH/CY, 0.79 CY/MH, 120.00 hourPlace Slab Concrete with Pump 1.00 EA 446.8Concrete Foreman 1.0 71.11 8,533Concrete Laborer 4.0 57.03 27,374Concrete Pump Operator 1.0 70.88 8,506124 YPH Trailer Mounted Concrete Pump 1.0 65.75 7,890Concrete Vibrator-Normal 2.0 0.54 13010 KW Generator Set (Gas) 2.0 4.93 1,183Fabric 3,333.0 SY 9.00 29,9974000 PSI (30MPA) Readymix Concrete 596.4 CY 160.00 95,424Control Structure 1.00 LS 1,339 86,411 6,381 7,116 100,633 70,000 270,5421,339.44 86,411.16 6,381.13 7,116.00 100,633.30 70,000.00 270,541.5950 Outlet Tower 179.00 CY 1,339 86,411 6,381 7,116 100,633 200,5427.48 482.74 35.65 39.75 562.20 1,120.3410 Tower Concrete 179.00 CY 1,339 86,411 6,381 7,116 100,633 200,5427.48 482.74 35.65 39.75 562.20 1,120.3410 Tower Concrete 179.00 CY 1,339 86,411 6,381 7,116 100,633 200,5427.48 482.74 35.65 39.75 562.20 1,120.3410 Foundation Prep 225.00 SF 14 884 185 1,0690.06 3.93 0.82 4.75Prod=50.00 SF/hour, 0.060MH/SF, 16.67 SF/MH, 4.50 hourFoundation Prep 1.00 EA 237.54General Laborer 2.0 61.41 553Backhoe Operator 1.0 73.56 3311.7 CY Backhoe Loader (Case680) 1.0 35.51 16022" Smooth Drum Manual (Bomag 55) 1.0 5.65 2515 Build Base Slab Forms 240.00 SF 35 2,273 77 1,222 3,5720.15 9.47 0.32 5.09 14.88Prod=27.38 sf/hour, 0.146MH/sf, 6.84 sf/MH, 8.77 hourFabricate Light Formwork 1.00 EA 268.045Formsetter Foreman 1.0 66.60 584Formsetter 2.0 65.60 1,150Formsetter Helper 1.0 61.41 5385 Ton Flat Bed Truck 0.5 17.67 77Supply Light Wood Form 240.0 sf 5.09 1,22220 SSM Base Slab Forms 240.00 SF 61 3,961 155 240 4,3560.26 16.50 0.65 1.00 18.15Prod=27.38 sf/hour, 0.256MH/sf, 3.91 sf/MH, 8.77 hourSet Strip Slab on Grade Edge Forms 1.00 EA 469.49Formsetter Foreman 1.0 66.60 584Formsetter 4.0 65.60 2,300Formsetter Helper 2.0 61.41 1,0775 Ton Flat Bed Truck 1.0 17.67 155Form supply 240.0 SF 1.00 240Page 12 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost25 Place Concrete Base Slab 34.00 CY 19 1,219 166 5,712 7,0980.57 35.86 4.89 168.00 208.75Prod=15.70 CY/hour, 0.573MH/CY, 1.74 CY/MH, 2.17 hourPlace Slab Concrete with Pump 1.00 EA 639.6Concrete Foreman 1.0 71.11 154Concrete Laborer 3.0 57.03 371Vibrator Operator 2.0 61.41 266Concrete Truck Spotter 1.0 61.41 133Formsetter 1.0 65.60 142Concrete Pump Operator 1.0 70.88 154124 YPH Trailer Mounted Concrete Pump 1.0 65.75 142Concrete Vibrator-Normal 2.0 0.54 210 KW Generator Set (Gas) 2.0 4.93 214000 PSI (30MPA) Readymix Concrete 35.7 CY 160.00 5,71230 Finish Concrete Base Slab 225.00 SF 2 116 1160.01 0.52 0.52Prod=239.63 sf/hour, 0.008MH/sf, 119.81 sf/MH, 0.94 hourFinish Concrete with Trowel 1.00 EA 123.86Cement Finisher 2.0 61.93 11635 Cure Concrete Base Slab 465.00 SF 2 134 1340.00 0.29 0.29Cement Finisher 1.0 EA 61.93 2.17 hour40 Build Wall Forms 750.00 SF 139 9,068 410 38,348 47,8250.19 12.09 0.55 51.13 63.77Prod=32.29 SF/hour, 0.186MH/SF, 5.38 SF/MH, 23.23 hourFabricate Gang Formwork 1.00 EA 408.08Formsetter Foreman 1.0 66.60 1,547Formsetter 4.0 65.60 6,094Formsetter Helper 1.0 61.41 1,4265 Ton Flat Bed Truck 1.0 17.67 410Supply Circular Steel Form 750.0 SF 51.13 38,34845 SSM Wall Forms 5,100.00 SF 600 38,891 3,096 5,100 47,0860.12 7.63 0.61 1.00 9.23Prod=80.73 SF/hour, 0.118MH/SF, 8.50 SF/MH, 63.17 hourSet Strip Walls 1.00 EA 664.616Formsetter Foreman 1.0 66.60 4,207Formsetter 5.0 65.60 20,721Formsetter Helper 3.0 61.41 11,639Crane Operator Class A 0.5 73.56 2,32440 Ton Hydraulic Crane (Grove700) 0.4 78.34 1,9805 Ton Flat Bed Truck 1.0 17.67 1,116Form Supply 5,100.0 SF 1.00 5,10046 Waterstop at Walls 134.25 LF 11 734 987 1,7210.08 5.47 7.35 12.82Formsetter 2.0 EA 65.60 5.59 hour9" Waterstop 134.3 ft 7.35 98750 Joint Prep on Slab 215.00 SF 3 162 17 1790.01 0.75 0.08 0.83Prod=146.25 SF/hour, 0.014MH/SF, 73.13 SF/MH, 1.47 hourJoint Prep on Slab 1.00 EA 121.45General Laborer 1.0 61.41 90Helper 1.0 48.46 71150 CFM Diesel Compressor 1.0 11.58 17Page 13 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost55 Place Concrete Wall 140.00 CY 80 5,021 690 23,520 29,2310.57 35.86 4.93 168.00 208.79Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 8.92 hourPlace Retaining Wall Concrete with Pump 1.00 EA 640.22Concrete Foreman 1.0 71.11 634Concrete Laborer 3.0 57.03 1,526Vibrator Operator 2.0 61.41 1,096Concrete Truck Spotter 1.0 61.41 548Formsetter 1.0 65.60 585Concrete Pump Operator 1.0 70.88 632124 YPH Trailer Mounted Concrete Pump 1.0 65.75 5862-CY Concrete Bucket (Gravity) 1.0 0.62 6Concrete Vibrator-Normal 2.0 0.54 1010 KW Generator Set (Gas) 2.0 4.93 884,000 PSI (30 MPA) Readymix Concrete 147.0 cy 160.00 23,52060 Finish Concrete Wall 215.00 SF 2 91 910.01 0.42 0.42Prod=269.49 sf/hour, 0.007MH/sf, 134.75 sf/MH, 0.80 hourFinish Concrete with Float 1.00 EA 114.06Concrete Laborer 2.0 57.03 9165 Cure Concrete Wall 5,315.00 SF 27 1,646 532 2,1770.01 0.31 0.10 0.41Cement Finisher 1.0 EA 61.93 26.58 hourCure 5,315.0 SF 0.10 53270 Patch & Point Walls 5,100.00 SF 36 2,211 2,2110.01 0.43 0.43Cement Finisher 1.0 EA 61.93 35.70 hour75 Build Roof Forms 257.76 SF 36 2,328 876 4,142 7,3460.14 9.03 3.40 16.07 28.50Prod=28.70 sf/hour, 0.139MH/sf, 7.18 sf/MH, 8.98 hourFabricate Light Formwork 1.00 EA 356.725Formsetter Foreman 1.0 66.60 598Formsetter 2.0 65.60 1,178Formsetter Helper 1.0 61.41 55140 Ton Truck Crane 1.0 88.68 7965 Ton Flat Bed Truck 0.5 17.67 79Supply Symons Versiform 257.8 sf 15.57 4,013Jacks for shoring 257.8 sf 0.50 12980 SSM Roof Forms 257.76 SF 54 3,488 227 258 3,9720.21 13.53 0.88 1.00 15.41Prod=64.58 sf/hour, 0.209MH/sf, 4.78 sf/MH, 3.99 hourSet Strip Elevated Soffit Forms 1.00 EA 930.66Formsetter Foreman 1.0 66.60 266Formsetter 8.0 65.60 2,095Formsetter Helper 4.0 61.41 980Crane Operator Class A 0.5 73.56 14740 Ton Hydraulic Crane (Grove700) 0.5 78.34 1565 Ton Flat Bed Truck 1.0 17.67 71Form supply 257.8 SF 1.00 25885 Place Roof Concrete 5.00 CY 3 185 32 840 1,0570.60 37.03 6.37 168.00 211.40Prod=13.43 cy/hour, 0.596MH/cy, 1.68 cy/MH, 0.37 hourPlace Concrete with Truck Mounted Pump 1.00 EA 582.83Concrete Foreman 1.0 71.11 26Concrete Laborer 3.0 57.03 64Vibrator Operator 2.0 61.41 46Concrete Truck Spotter 1.0 61.41 23Concrete Pump Operator 1.0 70.88 26124 YPH Trailer Mounted Concrete Pump 1.0 65.75 24Concrete Vibrator-Normal 2.0 0.54 010 KW Generator Set (Gas) 2.0 4.93 41/2 Ton Pickup Truck 2x2 1.0 8.83 34,000 PSI (30 MPA) Readymix Concrete 5.2 cy 160.00 840Page 14 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost90 Finish Roof Concrete 44.75 SF 1 39 1 400.01 0.86 0.02 0.88Prod=143.73 sf/hour, 0.014MH/sf, 71.87 sf/MH, 0.31 hourFinish Concrete with a Power Screed 1.00 EA 127.2Cement Finisher 2.0 61.93 39Concrete Power Trowel-Walker 1.0 3.34 195 Cure Roof Concrete 229.12 SF 1 71 710.01 0.31 0.31Cement Finisher 1.0 EA 61.93 1.15 hour96 Patch & Point Roof 114.56 SF 1 50 500.01 0.43 0.43Cement Finisher 1.0 EA 61.93 0.80 hour98 Reinforcement 35,800.00 LB 213 13,842 449 26,850 41,1410.01 0.39 0.01 0.75 1.15Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 5.97 hourHandle Reinforcing Steel 1.00 EA 271.64Rodman Helper 2.0 61.41 733Crane Operator Class A 1.0 73.56 43920 Ton Truck Crane 1.0 58.07 3464 Tonne Forklift (JCB-8000lb) 1.0 17.19 103Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 32.49 hourPlace Reinforcing Steel 1.00 EA 390.01Rodman Foreman 1.0 66.52 2,161Rodman 4.0 65.52 8,514Rodman Helper 1.0 61.41 1,995Supply Rebar 35,800.0 LB 0.75 26,85055 Maintenance Building 80.00 SF 20,000 20,000250.00 250.0010 Maintenance Building 80.00 SF 20,000 20,000250.00 250.00Maintenance Building 80.0 SF 250.00 20,00058 Outlet Gates 2.00 EA 50,000 50,00025,000.00 25,000.00Outlet Gates 36in 2.0 EA 25,000.00 50,000Inlet/Outlet Pipe & Outlet1.00 LS 8,790 604,608 520,915 12,109 233,876 2,700 1,374,2088,789.76 604,608.28 520,914.81 12,109.00 233,876.40 2,700.00 1,374,208.4960 Outlet 1.00 LS 146 9,425 540 3,564 5,935 19,463146.04 9,424.75 539.84 3,564.00 5,934.61 19,463.2010 Outlet Structure Concrete 16.00 CY 146 9,425 540 3,564 5,935 19,4639.13 589.05 33.74 222.75 370.91 1,216.4510 Outlet Concrete 16.00 CY 146 9,425 540 3,564 5,935 19,4639.13 589.05 33.74 222.75 370.91 1,216.4510 Foundation Prep 154.00 SF 0 32 7 380.00 0.20 0.04 0.25Prod=960.00 SF/hour, 0.003MH/SF, 320.00 SF/MH, 0.16 hourFoundation Prep 1.00 EA 237.54General Laborer 2.0 61.41 20Backhoe Operator 1.0 73.56 121.7 CY Backhoe Loader (Case680) 1.0 35.51 622" Smooth Drum Manual (Bomag 55) 1.0 5.65 115 Build Base Slab Forms 50.00 SF 7 473 16 255 7440.15 9.47 0.32 5.09 14.88Prod=27.38 sf/hour, 0.146MH/sf, 6.84 sf/MH, 1.83 hourFabricate Light Formwork 1.00 EA 268.045Formsetter Foreman 1.0 66.60 122Formsetter 2.0 65.60 240Formsetter Helper 1.0 61.41 1125 Ton Flat Bed Truck 0.5 17.67 16Supply Light Wood Form 50.0 sf 5.09 255Page 15 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost20 SSM Base Slab Forms 50.00 SF 13 825 32 50 9080.26 16.50 0.65 1.00 18.15Prod=27.38 sf/hour, 0.256MH/sf, 3.91 sf/MH, 1.83 hourSet Strip Slab on Grade Edge Forms 1.00 EA 469.49Formsetter Foreman 1.0 66.60 122Formsetter 4.0 65.60 479Formsetter Helper 2.0 61.41 2245 Ton Flat Bed Truck 1.0 17.67 32Form Supplies 50.0 SF 1.00 5025 Place Concrete Base Slab 6.00 CY 3 215 29 1,008 1,2530.57 35.86 4.89 168.00 208.75Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 0.38 hourPlace Slab Concrete with Pump 1.00 EA 639.6Concrete Foreman 1.0 71.11 27Concrete Laborer 3.0 57.03 65Vibrator Operator 2.0 61.41 47Concrete Truck Spotter 1.0 61.41 23Formsetter 1.0 65.60 25Concrete Pump Operator 1.0 70.88 27124 YPH Trailer Mounted Concrete Pump 1.0 65.75 25Concrete Vibrator-Normal 2.0 0.54 010 KW Generator Set (Gas) 2.0 4.93 44000 PSI (30MPA) Readymix Concrete 6.3 cy 160.00 1,00830 Finish Concrete Base Slab 154.00 SF 1 80 800.01 0.52 0.52Prod=239.63 sf/hour, 0.008MH/sf, 119.81 sf/MH, 0.64 hourFinish Concrete with Trowel 1.00 EA 123.86Cement Finisher 2.0 61.93 8035 Cure Concrete Base Slab 204.00 SF 1 59 590.00 0.29 0.29Cement Finisher 1.0 EA 61.93 0.95 hour40 Build Wall Forms 200.00 SF 37 2,418 109 3,114 5,6410.19 12.09 0.55 15.57 28.21Prod=32.29 sf/hour, 0.186MH/sf, 5.38 sf/MH, 6.19 hourFabricate Gang Formwork 1.00 EA 408.08Formsetter Foreman 1.0 66.60 412Formsetter 4.0 65.60 1,625Formsetter Helper 1.0 61.41 3805 Ton Flat Bed Truck 1.0 17.67 109Supply Symons Versiform 200.0 sf 15.57 3,11445 SSM Wall Forms 400.00 SF 47 3,050 243 400 3,6930.12 7.63 0.61 1.00 9.23Prod=80.73 sf/hour, 0.118MH/sf, 8.50 sf/MH, 4.95 hourSet Strip Retaining Walls 1.00 EA 664.616Formsetter Foreman 1.0 66.60 330Formsetter 5.0 65.60 1,625Formsetter Helper 3.0 61.41 913Crane Operator Class A 0.5 73.56 18240 Ton Hydraulic Crane (Grove700) 0.4 78.34 1555 Ton Flat Bed Truck 1.0 17.67 88Form Supplies 400.0 SF 1.00 400Page 16 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost50 Joint Prep on Slab 50.00 SF 1 38 4 420.01 0.75 0.08 0.83Prod=146.25 SF/hour, 0.014MH/SF, 73.13 SF/MH, 0.34 hourJoint Prep on Slab 1.00 EA 121.45General Laborer 1.0 61.41 21Helper 1.0 48.46 17150 CFM Diesel Compressor 1.0 11.58 455 Place Concrete Wall 10.00 CY 6 359 49 1,680 2,0880.57 35.86 4.93 168.00 208.79Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 0.64 hourPlace Retaining Wall Concrete with Pump 1.00 EA 640.22Concrete Foreman 1.0 71.11 45Concrete Laborer 3.0 57.03 109Vibrator Operator 2.0 61.41 78Concrete Truck Spotter 1.0 61.41 39Formsetter 1.0 65.60 42Concrete Pump Operator 1.0 70.88 45124 YPH Trailer Mounted Concrete Pump 1.0 65.75 422-CY Concrete Bucket (Gravity) 1.0 0.62 0Concrete Vibrator-Normal 2.0 0.54 110 KW Generator Set (Gas) 2.0 4.93 64,000 PSI (30 MPA) Readymix Concrete 10.5 cy 160.00 1,68060 Finish Concrete Wall 50.00 SF 0 21 210.01 0.42 0.42Prod=269.49 sf/hour, 0.007MH/sf, 134.75 sf/MH, 0.19 hourFinish Concrete with Float 1.00 EA 114.06Concrete Laborer 2.0 57.03 2165 Cure Concrete Wall 450.00 SF 2 139 1390.01 0.31 0.31Cement Finisher 1.0 EA 61.93 2.25 hour70 Patch & Point Walls 400.00 SF 3 173 1730.01 0.43 0.43Cement Finisher 1.0 EA 61.93 2.80 hour75 Reinforcement 3,989.47 LB 24 1,542 50 2,992 4,5850.01 0.39 0.01 0.75 1.15Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 0.66 hourHandle Reinforcing Steel 1.00 EA 271.64Rodman Helper 2.0 61.41 82Crane Operator Class A 1.0 73.56 4920 Ton Truck Crane 1.0 58.07 394 Tonne Forklift (JCB-8000lb) 1.0 17.19 11Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 3.62 hourPlace Reinforcing Steel 1.00 EA 390.01Rodman Foreman 1.0 66.52 241Rodman 4.0 65.52 949Rodman Helper 1.0 61.41 222Supply Rebar 3,989.5 lb 0.75 2,99263 Inlet Outlet Pipe 536.00 LF 8,629 594,194 519,869 8,545 226,372 2,700 1,351,68016.10 1,108.57 969.90 15.94 422.34 5.04 2,521.7915 Inlet Outlet Pipe Lay Steel Pipe 536.00 LF 536 33,475 13,872 193,310 2,700 243,3571.00 62.45 25.88 360.65 5.04 454.02Prod=8.00 LF/hour, 1.000MH/LF, 1.00 LF/MH, 67.00 hourLay Pipe 1.00 EA 706.67Foreman 1.0 71.37 4,782Equip Oper Cl 3 (Backhoe) 1.0 73.56 4,929Equip Oper Cl 3 (Loader) 1.0 70.88 4,749Labor Cl 5 (Pipe) 4.0 57.03 15,284Truck Driver Cl 4 (Water) 1.0 55.70 3,7323.5 CY Loader (Cat 950) 1.0 58.84 3,9422.6 CY Backhoe (Cat 350) 1.0 98.70 6,613Jumping Jack Handheld Packer 1.0 4.12 27624" Smooth Drum Manual (Bomag 60) 1.0 6.41 4293/4 Ton Pickup Truck 2x2 1.0 11.14 7463000 Gallon Watertruck 1.0 27.83 1,865Pipe Bedding 114.2 CY 50.00 5,71036in Steel Pipe 536.0 LF 350.00 187,600Weld 36in Pipe 15.0 JTS 180.00 2,700Page 17 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost17 Inlet /Outlet Backfill 29,964.00 CY 2,397 167,509 173,795 341,3040.08 5.59 5.80 11.39Prod=150.00 CY/hour, 0.080MH/CY, 12.50 CY/MH, 199.76 hourHaul Place Backfill 1.00 EA 1708.57Foreman 1.0 71.37 14,257Equip Oper Cl 3 (Dozer) 2.0 70.88 28,318Equip Oper Cl 3 Grader) 1.0 70.88 14,159Equip Oper Cl 3 (Backhoe) 1.0 73.56 14,694Equip Oper Cl 4 (Roller) 1.0 70.88 14,159Equip Oper Cl 7 Art truck 4.0 70.88 56,636Equip Oper Cl 6 Gradechecker 1.0 70.88 14,159Truck Driver Cl 4 (Water) 1.0 55.70 11,127170 Hsp Bulldozer ( Cat D6 ) 2.0 68.57 27,395200 Hsp Grader (Cat 14G) 1.0 87.75 17,5292.6 CY Backhoe (Cat 350) 1.0 98.70 19,71630 Ton Articulated Truck (Cat D300) 4.0 90.44 72,26530 Ton Compactor 315 hsp (Cat 825) 1.0 140.24 28,0143/4 Ton Pickup Truck 2x2 1.0 11.14 2,2255000 Gallon Watertanker 1.0 33.29 6,65018 Inlet Outlet Pipe Excavation 74,412.00 CY 4,980 346,992 329,273 676,2650.07 4.66 4.43 9.09Prod=149.43 CY/hour, 0.067MH/CY, 14.94 CY/MH, 497.99 hourExcavation Crew 1.00 EA 1358Foreman 1.0 71.37 35,541Equip Oper Cl 3 (Backhoe) 1.0 73.56 36,632Equip Oper Cl 3 (Grader) 1.0 70.88 35,297Equip Oper Cl 3 (Dozer) 1.0 70.88 35,297Equip Oper Cl 7 Art truck 4.0 70.88 141,189Equip Oper Cl 6 Gradechecker 1.0 70.88 35,297Truck Driver Cl 4 (Water) 1.0 55.70 27,738170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 34,147200 Hsp Grader (Cat 14G) 1.0 87.75 43,6982.6 CY Backhoe (Cat 350) 1.0 98.70 49,15130 Ton Articulated Truck (Cat D300) 4.0 90.44 180,1513/4 Ton Pickup Truck 2x2 1.0 11.14 5,5485000 Gallon Watertanker 1.0 33.29 16,57820 Concrete Encase Outlet Pipe 93.00 CY 716 46,218 2,929 8,545 33,062 90,7547.70 496.97 31.49 91.88 355.50 975.8510 Concrete Encase Pipe 250LF 93.00 CY 716 46,218 2,929 8,545 33,062 90,7547.70 496.97 31.49 91.88 355.50 975.8510 Foundation Prep 1,250.00 SF 4 256 54 3090.00 0.20 0.04 0.25Prod=960.00 SF/hour, 0.003MH/SF, 320.00 SF/MH, 1.30 hourFoundation Prep 1.00 EA 237.54General Laborer 2.0 61.41 160Backhoe Operator 1.0 73.56 961.7 CY Backhoe Loader (Case680) 1.0 35.51 4622" Smooth Drum Manual (Bomag 55) 1.0 5.65 715 Build Wall Forms 1,000.00 SF 186 12,090 547 5,560 18,1970.19 12.09 0.55 5.56 18.20Prod=32.29 SF/hour, 0.186MH/SF, 5.38 SF/MH, 30.97 hourFabricate Gang Formwork 1.00 EA 408.08Formsetter Foreman 1.0 66.60 2,062Formsetter 4.0 65.60 8,126Formsetter Helper 1.0 61.41 1,9025 Ton Flat Bed Truck 1.0 17.67 547Supply Wood Form Wood Walers & Strongbacks 1,000.0 SF 5.56 5,560Page 18 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost20 SSM Wall Forms 2,600.00 SF 306 19,827 1,578 2,600 24,0050.12 7.63 0.61 1.00 9.23Prod=80.73 sf/hour, 0.118MH/sf, 8.50 sf/MH, 32.21 hourSet Strip Retaining Walls 1.00 EA 664.616Formsetter Foreman 1.0 66.60 2,145Formsetter 5.0 65.60 10,564Formsetter Helper 3.0 61.41 5,933Crane Operator Class A 0.5 73.56 1,18540 Ton Hydraulic Crane (Grove700) 0.4 78.34 1,0095 Ton Flat Bed Truck 1.0 17.67 569Form Supplies 2,600.0 SF 1.00 2,60025 Place Concrete 93.00 CY 53 3,335 458 15,624 19,4170.57 35.86 4.93 168.00 208.79Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 5.93 hourPlace Retaining Wall Concrete with Pump 1.00 EA 640.22Concrete Foreman 1.0 71.11 421Concrete Laborer 3.0 57.03 1,014Vibrator Operator 2.0 61.41 728Concrete Truck Spotter 1.0 61.41 364Formsetter 1.0 65.60 389Concrete Pump Operator 1.0 70.88 420124 YPH Trailer Mounted Concrete Pump 1.0 65.75 3902-CY Concrete Bucket (Gravity) 1.0 0.62 4Concrete Vibrator-Normal 2.0 0.54 610 KW Generator Set (Gas) 2.0 4.93 584,000 PSI (30 MPA) Readymix Concrete 97.7 cy 160.00 15,62430 Finish Concrete 1,250.00 SF 9 529 5290.01 0.42 0.42Prod=269.49 sf/hour, 0.007MH/sf, 134.75 sf/MH, 4.64 hourFinish Concrete with Float 1.00 EA 114.06Concrete Laborer 2.0 57.03 52935 Cure Concrete Wall 3,850.00 SF 19 1,192 385 1,5770.01 0.31 0.10 0.41Cement Finisher 1.0 EA 61.93 19.25 hourCure materials 3,850.0 SF 0.10 38540 Reinforcement 23,250.00 LB 138 8,989 292 17,438 26,7190.01 0.39 0.01 0.75 1.15Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 3.88 hourHandle Reinforcing Steel 1.00 EA 271.64Rodman Helper 2.0 61.41 476Crane Operator Class A 1.0 73.56 28520 Ton Truck Crane 1.0 58.07 2254 Tonne Forklift (JCB-8000lb) 1.0 17.19 67Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 21.10 hourPlace Reinforcing Steel 1.00 EA 390.01Rodman Foreman 1.0 66.52 1,403Rodman 4.0 65.52 5,529Rodman Helper 1.0 61.41 1,296Supply Rebar 23,250.0 lb 0.75 17,43865 Riprap Outlet 15.00 CY 15 990 506 1,570 3,0661.00 65.97 33.74 104.67 204.3810 Place Riprap & Bedding 15.00 CY 15 990 506 1,570 3,0661.00 65.97 33.74 104.67 204.38Prod=5.00 CY/hour, 1.000MH/CY, 1.00 CY/MH, 3.00 hourPlace RipRap 1.00 EA 498.55Foreman 1.0 71.37 214Equip Oper Cl 3 (Backhoe) 1.0 73.56 221Equip Oper Cl 3 (Loader) 1.0 70.88 213Labor Cl 5 (Pipe) 2.0 57.03 3423.5 CY Loader (Cat 950) 1.0 58.84 1772.6 CY Backhoe (Cat 350) 1.0 98.70 2963/4 Ton Pickup Truck 2x2 1.0 11.14 33Riprap 30.0 TN 45.00 1,350Bedding 4.4 CY 50.00 220Page 19 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total CostIntake 1.00 LS 159 10,240 610 2,323 10,313 35,000 58,487158.70 10,240.05 610.45 2,323.17 10,313.29 35,000.00 58,486.9570 Intake 1.00 LS 159 10,240 610 2,323 10,313 35,000 58,487158.70 10,240.05 610.45 2,323.17 10,313.29 35,000.00 58,486.9510 Intake Concrete 31.00 CY 159 10,240 610 2,323 10,313 23,4875.12 330.32 19.69 74.94 332.69 757.6410 Intake Concrete 31.00 CY 159 10,240 610 2,323 10,313 23,4875.12 330.32 19.69 74.94 332.69 757.6410 Foundation Prep 140.48 SF 0 29 6 350.00 0.20 0.04 0.25Prod=960.00 SF/hour, 0.003MH/SF, 320.00 SF/MH, 0.15 hourFoundation Prep 1.00 EA 237.54General Laborer 2.0 61.41 18Backhoe Operator 1.0 73.56 111.7 CY Backhoe Loader (Case680) 1.0 35.51 522" Smooth Drum Manual (Bomag 55) 1.0 5.65 115 Build Base Slab Forms 28.31 SF 1 90 3 48 1410.05 3.17 0.11 1.70 4.97Prod=27.38 sf/hour, 0.146MH/sf, 6.84 sf/MH, 0.35 hourFabricate Light Formwork 1.00 EA 268.045Formsetter Foreman 1.0 66.60 23Formsetter 2.0 65.60 45Formsetter Helper 1.0 61.41 215 Ton Flat Bed Truck 0.5 17.67 3Supply Light Wood Form 9.5 sf 5.09 4820 SSM Base Slab Forms 28.31 SF 7 467 18 4850.26 16.50 0.65 17.15Prod=27.38 sf/hour, 0.256MH/sf, 3.91 sf/MH, 1.03 hourSet Strip Slab on Grade Edge Forms 1.00 EA 469.49Formsetter Foreman 1.0 66.60 69Formsetter 4.0 65.60 271Formsetter Helper 2.0 61.41 1275 Ton Flat Bed Truck 1.0 17.67 1825 Place Concrete Base Slab 10.44 CY 6 375 51 1,754 2,1800.57 35.86 4.89 168.00 208.75Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 0.67 hourPlace Slab Concrete with Pump 1.00 EA 639.6Concrete Foreman 1.0 71.11 47Concrete Laborer 3.0 57.03 114Vibrator Operator 2.0 61.41 82Concrete Truck Spotter 1.0 61.41 41Formsetter 1.0 65.60 44Concrete Pump Operator 1.0 70.88 47124 YPH Trailer Mounted Concrete Pump 1.0 65.75 44Concrete Vibrator-Normal 2.0 0.54 110 KW Generator Set (Gas) 2.0 4.93 74000 PSI (30MPA) Readymix Concrete 11.0 CY 160.00 1,75430 Finish Concrete Base Slab 140.48 SF 1 73 730.01 0.52 0.52Prod=239.63 sf/hour, 0.008MH/sf, 119.81 sf/MH, 0.59 hourFinish Concrete with Trowel 1.00 EA 123.86Cement Finisher 2.0 61.93 7335 Cure Concrete Base Slab 168.79 SF 1 49 490.00 0.29 0.29Cement Finisher 1.0 EA 61.93 0.79 hour40 Build Wall Forms 447.71 SF 28 1,804 82 2,323 4,2090.06 4.03 0.18 5.19 9.40Prod=32.29 sf/hour, 0.186MH/sf, 5.38 sf/MH, 4.62 hourFabricate Gang Formwork 1.00 EA 408.08Formsetter Foreman 1.0 66.60 308Formsetter 4.0 65.60 1,212Formsetter Helper 1.0 61.41 2845 Ton Flat Bed Truck 1.0 17.67 82Supply Symons Versiform 149.2 sf 15.57 2,323Page 20 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost45 SSM Wall Forms 447.71 SF 53 3,414 272 3,6860.12 7.63 0.61 8.23Prod=80.73 sf/hour, 0.118MH/sf, 8.50 sf/MH, 5.55 hourSet Strip Retaining Walls 1.00 EA 664.616Formsetter Foreman 1.0 66.60 369Formsetter 5.0 65.60 1,819Formsetter Helper 3.0 61.41 1,022Crane Operator Class A 0.5 73.56 20440 Ton Hydraulic Crane (Grove700) 0.4 78.34 1745 Ton Flat Bed Truck 1.0 17.67 9850 Joint Prep on Slab 27.00 SF 0 20 2 220.01 0.75 0.08 0.83Prod=146.25 SF/hour, 0.014MH/SF, 73.13 SF/MH, 0.18 hourJoint Prep on Slab 1.00 EA 121.45General Laborer 1.0 61.41 11Helper 1.0 48.46 9150 CFM Diesel Compressor 1.0 11.58 255 Place Concrete Wall 16.15 CY 9 579 80 2,714 3,3730.57 35.86 4.93 168.00 208.79Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 1.03 hourPlace Retaining Wall Concrete with Pump 1.00 EA 640.22Concrete Foreman 1.0 71.11 73Concrete Laborer 3.0 57.03 176Vibrator Operator 2.0 61.41 126Concrete Truck Spotter 1.0 61.41 63Formsetter 1.0 65.60 68Concrete Pump Operator 1.0 70.88 73124 YPH Trailer Mounted Concrete Pump 1.0 65.75 682-CY Concrete Bucket (Gravity) 1.0 0.62 1Concrete Vibrator-Normal 2.0 0.54 110 KW Generator Set (Gas) 2.0 4.93 104,000 PSI (30 MPA) Readymix Concrete 17.0 CY 160.00 2,71460 Finish Concrete Wall 27.00 SF 0 11 110.01 0.42 0.42Prod=269.49 sf/hour, 0.007MH/sf, 134.75 sf/MH, 0.10 hourFinish Concrete with Float 1.00 EA 114.06Concrete Laborer 2.0 57.03 1165 Cure Concrete Wall 474.71 SF 2 147 1470.00 0.31 0.31Cement Finisher 1.0 EA 61.93 2.37 hour70 Patch & Point Walls 447.71 SF 3 194 1940.01 0.43 0.43Cement Finisher 1.0 EA 61.93 3.13 hour75 Reinforcement 7,729.61 LB 46 2,989 97 5,797 8,8830.01 0.39 0.01 0.75 1.15Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 1.29 hourHandle Reinforcing Steel 1.00 EA 271.64Rodman Helper 2.0 61.41 158Crane Operator Class A 1.0 73.56 9520 Ton Truck Crane 1.0 58.07 754 Tonne Forklift (JCB-8000lb) 1.0 17.19 22Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 7.01 hourPlace Reinforcing Steel 1.00 EA 390.01Rodman Foreman 1.0 66.52 467Rodman 4.0 65.52 1,838Rodman Helper 1.0 61.41 431Supply Rebar 7,729.6 lb 0.75 5,79720 Trashrack & Stoplogs 1.00 EA 35,000 35,00035,000.00 35,000.00Trashrack 1.0 LS 35,000.00 35,000Stetson Creek Diversion 1.00 LS 3,956 256,027 24,067 56,177 249,042 119,532 704,8453,956.31 256,027.19 24,067.06 56,177.14 249,041.73 119,532.00 704,845.10Page 21 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost85 Diversion Dam Stetson Creek 1.00 LS 3,956 256,027 24,067 56,177 249,042 119,532 704,8453,956.31 256,027.19 24,067.06 56,177.14 249,041.73 119,532.00 704,845.1010 Clearing 0.30 AC 85 5,531 1,977 7,508283.33 18,436.00 6,589.83 25,025.83Prod=0.06 AC/hour, 283.333MH/AC, 0.00 AC/MH, 5.00 hourClear Right of Way 1.00 EA 1501.55Pusher 1.0 75.00 375General Laborer 10.0 61.41 3,071Equipment Foreman 1.0 75.00 375Backhoe Operator 1.0 73.56 368Dozer Operator 1.0 70.88 354Truck Driver 2.0 63.37 634Oiler 1.0 70.88 354305 Hsp Bulldozer ( Cat D8 ) 1.0 136.76 6842.6 CY Backhoe (Cat 350) 1.0 98.70 49420 Ton (10 CY) Tandem Truck 1.0 38.17 19110 Ton All Terrain Vehicle ( Nodwell 110 ) 1.0 81.61 4083/4 Ton Pickup Truck 2x2 1.0 11.14 563/4 Ton Crew Cab Truck 1.0 11.34 575 Ton Flat Bed Truck 1.0 17.67 8812 Stetson Creek Structure Excavation 1,008.00 CY 121 8,412 7,707 8,532 24,6520.12 8.35 7.65 8.46 24.46Prod=75.00 CY/hour, 0.120MH/CY, 8.33 CY/MH, 13.44 hourExcavation Crew 1.00 EA 1199.37Foreman 1.0 71.37 959Equip Oper Cl 3 (Backhoe) 1.0 73.56 989Equip Oper Cl 3 (Dozer) 1.0 70.88 953Equip Oper Cl 7 Art truck 4.0 70.88 3,811Equip Oper Cl 6 Gradechecker 1.0 70.88 953Truck Driver Cl 4 (Water) 1.0 55.70 749170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 9222.6 CY Backhoe (Cat 350) 1.0 98.70 1,32730 Ton Articulated Truck (Cat D300) 4.0 90.44 4,8623/4 Ton Pickup Truck 2x2 1.0 11.14 1505000 Gallon Watertanker 1.0 33.29 447Drill & Shoot 711.0 CY 12.00 8,53215 Concrete Stetson Creek Diversion Structure 719.00 CY 3,707 239,210 14,158 56,177 239,202 548,7475.16 332.70 19.69 78.13 332.69 763.2110 Diversion structure Concrete 719.00 CY 3,707 239,210 14,158 56,177 239,202 548,7475.16 332.70 19.69 78.13 332.69 763.2110 Foundation Prep 3,258.21 SF 10 667 140 8060.00 0.20 0.04 0.25Prod=960.00 SF/hour, 0.003MH/SF, 320.00 SF/MH, 3.39 hourFoundation Prep 1.00 EA 237.54General Laborer 2.0 61.41 417Backhoe Operator 1.0 73.56 2501.7 CY Backhoe Loader (Case680) 1.0 35.51 12122" Smooth Drum Manual (Bomag 55) 1.0 5.65 1915 Build Base Slab Forms 656.56 SF 32 2,078 71 1,117 3,2660.05 3.17 0.11 1.70 4.97Prod=27.38 sf/hour, 0.146MH/sf, 6.84 sf/MH, 8.02 hourFabricate Light Formwork 1.00 EA 268.045Formsetter Foreman 1.0 66.60 534Formsetter 2.0 65.60 1,052Formsetter Helper 1.0 61.41 4925 Ton Flat Bed Truck 0.5 17.67 71Supply Light Wood Form 219.5 sf 5.09 1,11720 SSM Base Slab Forms 656.56 SF 168 10,836 424 11,2600.26 16.50 0.65 17.15Prod=27.38 sf/hour, 0.256MH/sf, 3.91 sf/MH, 23.98 hourSet Strip Slab on Grade Edge Forms 1.00 EA 469.49Formsetter Foreman 1.0 66.60 1,597Formsetter 4.0 65.60 6,293Formsetter Helper 2.0 61.41 2,9465 Ton Flat Bed Truck 1.0 17.67 424Page 22 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost25 Place Concrete Base Slab 242.19 CY 139 8,686 1,183 40,688 50,5570.57 35.86 4.89 168.00 208.75Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 15.43 hourPlace Slab Concrete with Pump 1.00 EA 639.6Concrete Foreman 1.0 71.11 1,097Concrete Laborer 3.0 57.03 2,640Vibrator Operator 2.0 61.41 1,895Concrete Truck Spotter 1.0 61.41 948Formsetter 1.0 65.60 1,012Concrete Pump Operator 1.0 70.88 1,094124 YPH Trailer Mounted Concrete Pump 1.0 65.75 1,015Concrete Vibrator-Normal 2.0 0.54 1710 KW Generator Set (Gas) 2.0 4.93 1524000 PSI (30MPA) Readymix Concrete 254.3 cy 160.00 40,68830 Finish Concrete Base Slab 3,258.21 SF 27 1,684 1,6840.01 0.52 0.52Prod=239.63 sf/hour, 0.008MH/sf, 119.81 sf/MH, 13.60 hourFinish Concrete with Trowel 1.00 EA 123.86Cement Finisher 2.0 61.93 1,68435 Cure Concrete Base Slab 3,914.77 SF 18 1,130 1,1300.00 0.29 0.29Cement Finisher 1.0 EA 61.93 18.25 hour40 Build Wall Forms 10,383.87 SF 643 41,840 1,894 53,882 97,6160.06 4.03 0.18 5.19 9.40Prod=32.29 sf/hour, 0.186MH/sf, 5.38 sf/MH, 107.17 hourFabricate Gang Formwork 1.00 EA 408.08Formsetter Foreman 1.0 66.60 7,137Formsetter 4.0 65.60 28,121Formsetter Helper 1.0 61.41 6,5815 Ton Flat Bed Truck 1.0 17.67 1,894Supply Symons Versiform 3,460.7 sf 15.57 53,88245 SSM Wall Forms 10,383.87 SF 1,222 79,183 6,303 85,4870.12 7.63 0.61 8.23Prod=80.73 sf/hour, 0.118MH/sf, 8.50 sf/MH, 128.63 hourSet Strip Retaining Walls 1.00 EA 664.616Formsetter Foreman 1.0 66.60 8,566Formsetter 5.0 65.60 42,189Formsetter Helper 3.0 61.41 23,697Crane Operator Class A 0.5 73.56 4,73140 Ton Hydraulic Crane (Grove700) 0.4 78.34 4,0315 Ton Flat Bed Truck 1.0 17.67 2,27350 Joint Prep on Slab 626.29 SF 9 470 50 5200.01 0.75 0.08 0.83Prod=146.25 SF/hour, 0.014MH/SF, 73.13 SF/MH, 4.28 hourJoint Prep on Slab 1.00 EA 121.45General Laborer 1.0 61.41 263Helper 1.0 48.46 208150 CFM Diesel Compressor 1.0 11.58 5055 Place Concrete Wall 374.64 CY 215 13,436 1,845 62,939 78,2210.57 35.86 4.93 168.00 208.79Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 23.87 hourPlace Retaining Wall Concrete with Pump 1.00 EA 640.22Concrete Foreman 1.0 71.11 1,697Concrete Laborer 3.0 57.03 4,084Vibrator Operator 2.0 61.41 2,932Concrete Truck Spotter 1.0 61.41 1,466Formsetter 1.0 65.60 1,566Concrete Pump Operator 1.0 70.88 1,692124 YPH Trailer Mounted Concrete Pump 1.0 65.75 1,5692-CY Concrete Bucket (Gravity) 1.0 0.62 15Concrete Vibrator-Normal 2.0 0.54 2610 KW Generator Set (Gas) 2.0 4.93 2354,000 PSI (30 MPA) Readymix Concrete 393.4 cy 160.00 62,939Page 23 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost60 Finish Concrete Wall 626.29 SF 5 265 2650.01 0.42 0.42Prod=269.49 sf/hour, 0.007MH/sf, 134.75 sf/MH, 2.32 hourFinish Concrete with Float 1.00 EA 114.06Concrete Laborer 2.0 57.03 26565 Cure Concrete Wall 11,010.16 SF 55 3,409 3,4090.00 0.31 0.31Cement Finisher 1.0 EA 61.93 55.05 hour70 Patch & Point Walls 10,383.87 SF 73 4,502 4,5020.01 0.43 0.43Cement Finisher 1.0 EA 61.93 72.69 hour75 Reinforcement 179,276.97 LB 1,066 69,316 2,249 134,458 206,0220.01 0.39 0.01 0.75 1.15Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 29.88 hourHandle Reinforcing Steel 1.00 EA 271.64Rodman Helper 2.0 61.41 3,670Crane Operator Class A 1.0 73.56 2,19820 Ton Truck Crane 1.0 58.07 1,7354 Tonne Forklift (JCB-8000lb) 1.0 17.19 514Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 162.68 hourPlace Reinforcing Steel 1.00 EA 390.01Rodman Foreman 1.0 66.52 10,822Rodman 4.0 65.52 42,636Rodman Helper 1.0 61.41 9,990Supply Rebar 179,277.0 lb 0.75 134,45880 Waterstop at Walls 312.20 LF 26 1,707 2,295 4,0010.08 5.47 7.35 12.82Formsetter 2.0 EA 65.60 13.01 hour9" Waterstop 312.2 ft 7.35 2,29520 Diversion Structure Mechanical 1.00 LS 43 2,874 224 9,840 111,000 123,93943.40 2,874.39 224.35 9,840.00 111,000.00 123,938.7410 48in Sluice Gate 1.00 EA 50,000 50,00050,000.00 50,000.00Sluice Gate 48in 1.0 EA 50,000.00 50,00015 36in Sluice Gate 1.00 EA 36,000 36,00036,000.00 36,000.00Sluice Gate 30in 1.0 EA 36,000.00 36,00020 Trashrack 28 x 28 1.00 EA 25,000 25,00025,000.00 25,000.00Trashrack 1.0 EA 25,000.00 25,00021 Safety Railing 60.00 LF 23 1,514 145 3,240 4,8990.38 25.23 2.42 54.00 81.65Prod=7.89 FT/hour, 0.380MH/FT, 2.63 FT/MH, 7.60 hourInstall Steel Railings 1.00 EA 218.27Welder 1.0 66.98 509Carpenter Foreman 1.0 66.60 506Carpenter 1.0 65.60 49910 KW Generator Set (Gas) 1.0 4.93 37250 Amp Diesel Welder 1.0 4.75 36Acetylene Cutting Torch 1.0 2.24 17Diamond Core Drill (Hilti) 1.0 7.17 54Galv Steel Rail 1.5in 60.0 FT 54.00 3,24022 Grating 264.00 SF 21 1,361 79 6,600 8,0400.08 5.15 0.30 25.00 30.45Prod=60.87 SF/hour, 0.078MH/SF, 12.82 SF/MH, 4.34 hourFloor Grating 1.00 EA 332.0075Ironworker Foreman 0.5 66.52 144Ironworker 4.0 65.52 1,137Crane Operator Class A 0.3 73.56 80250 Amp Diesel Welder 1.0 4.75 21Acetylene Cutting Torch 1.0 2.24 1020 Ton Hydraulic Crane (Grove58) 0.3 45.15 49Steel Grating 264.0 SF 25.00 6,600Page 24 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total CostInstrumentation 1.00 LS 210,000 210,000210,000.00 210,000.0086 Instrumentation (Floe Meters & Gauges) 1.00 LS 210,000 210,000210,000.00 210,000.00Instrumentation (Flow Meters & Gauges) 1.0 LS 210,000.00 210,000Stetson Creek Pipeline 1.00 LS 16,937 1,066,065 593,592 117,673 3,008,232 20,000 449,000 5,254,56316,937.23 1,066,065.33 593,592.28 117,672.80 3,008,232.49 20,000.00 449,000.00 5,254,562.9091 Bridge 1.00 LS 225,000 225,000225,000.00 225,000.0010 Bridge 1.00 LS 225,000 225,000225,000.00 225,000.00Bridge 1.0 LS 225,000.00 225,00092 Clearing 13.00 AC 905 58,022 12,779 70,80069.61 4,463.20 982.98 5,446.1910 Clearing 13.00 AC 905 58,022 12,779 70,80069.61 4,463.20 982.98 5,446.19Prod=262.64 ft/hour, 0.107MH/ft, 9.38 ft/MH, 32.32 hourClear Right of Way 1.00 EA 2190.65Pusher 2.0 75.00 4,848General Laborer 20.0 61.41 39,695Equipment Foreman 1.0 75.00 2,424Backhoe Operator 1.0 73.56 2,377Dozer Operator 1.0 70.88 2,291Truck Driver 2.0 63.37 4,096Oiler 1.0 70.88 2,291305 Hsp Bulldozer ( Cat D8 ) 1.0 136.76 4,4202.6 CY Backhoe (Cat 350) 1.0 98.70 3,19020 Ton (10 CY) Tandem Truck 1.0 38.17 1,23410 Ton All Terrain Vehicle ( Nodwell 110 ) 1.0 81.61 2,6383/4 Ton Pickup Truck 2x2 1.0 11.14 3603/4 Ton Crew Cab Truck 1.0 11.34 3675 Ton Flat Bed Truck 1.0 17.67 57195 Pipeline 11,910.00 LF 15,308 957,711 546,198 54,173 2,958,232 140,000 4,656,3141.29 80.41 45.86 4.55 248.38 11.75 390.9610 Pipeline Common Excavation 16,120.00 CY 927 61,539 67,563 129,1020.06 3.82 4.19 8.01Prod=102.58 CY/hour, 0.058MH/CY, 17.39 CY/MH, 157.14 hourMain Trench Excavation, Pipe 1.00 EA 821.568Equipment Foreman 1.0 75.00 11,786Packer Operator 0.3 70.88 3,341Spotter 1.0 57.03 8,962Water Truck Driver 0.3 63.37 2,987Backhoe Operator 1.0 73.56 11,559Off Hwy Truck Driver 2.3 63.37 22,9032.6 CY Backhoe (Cat 350) 1.0 142.59 22,40730 Ton Articulated Truck (Cat D300) 2.0 124.55 39,1448 Ton Compactor 66" (Cat 433) 0.3 46.37 2,1863/4 Ton Crew Cab Truck 1.0 11.34 1,7823000 Gallon Watertruck 0.3 43.37 2,04515 Pipeline Rock Excavation 13,680.00 CY 2,655 170,507 123,829 54,173 348,5090.19 12.46 9.05 3.96 25.48Page 25 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost10 Drill & Shoot 13,680.00 CY 1,250 77,857 21,658 54,173 153,6890.09 5.69 1.58 3.96 11.23Prod=262.64 CY/hour, 0.053MH/CY, 18.76 CY/MH, 52.09 hourDrill Rock 1.00 EA 1186.39Driller 4.0 62.13 12,945General Labor Foreman 1.0 58.00 3,021General Laborer 2.0 61.41 6,397Helper 4.0 59.98 12,497Truck Driver 1.0 63.37 3,301Mechanics Helper 1.0 65.00 3,386Oiler 1.0 70.88 3,692Hydraulic Drill 3" (AC1238/Tam400) 4.0 73.85 15,3873/4 Ton Pickup Truck 2x2 1.0 11.14 5803/4 Ton Crew Cab Truck 1.0 11.34 591Prod=262.64 FT/hour, 0.038MH/FT, 26.26 FT/MH, 52.09 hourBlast Rock 1.00 EA 724.17Powderman 2.0 62.13 6,472General Labor Foreman 1.0 58.00 3,021General Laborer 5.0 61.41 15,993Backhoe Operator 1.0 73.56 3,832Truck Driver 1.0 63.37 3,3011.7 CY Backhoe ( JD 790 ) 1.0 68.92 3,5903/4 Ton Crew Cab Truck 1.0 11.34 5915 Ton Flat Bed Truck 1.0 17.67 920Drill Bits & Steel (65mm) 2-1/2 inch 13,680.0 FT 0.72 9,850Ammonium Nitrate Fuel Oil 13,680.0 LB 0.50 6,840Electric Blasting Caps 13,680.0 EA 2.74 37,48315 Excavate Rock 13,680.00 CY 1,404 92,649 102,171 194,8200.10 6.77 7.47 14.24Prod=75.00 CY/hour, 0.103MH/CY, 9.74 CY/MH, 182.40 hourMain Trench Excavation, Pipe 1.00 EA 1068.093Equipment Foreman 1.0 75.00 13,680Dozer Operator 1.0 70.88 12,929Packer Operator 0.3 73.90 4,044Spotter 1.0 57.03 10,402Water Truck Driver 0.7 54.58 6,969Backhoe Operator 1.0 73.56 13,417Off Hwy Truck Driver 2.7 63.37 31,208170 Hsp Bulldozer ( Cat D6 ) 1.0 94.30 17,2002.6 CY Backhoe (Cat 350) 1.0 142.59 26,00830 Ton Articulated Truck (Cat D300) 2.0 124.55 45,4368 Ton Compactor 66" (Cat 433) 0.7 46.37 5,9213/4 Ton Crew Cab Truck 1.0 11.34 2,0683000 Gallon Watertruck 0.7 43.37 5,53716 Culvert Pipe 500.00 LF 333 20,968 11,854 24,351 57,1740.67 41.94 23.71 48.70 114.35Prod=11.25 LF/hour, 0.667MH/LF, 1.50 LF/MH, 44.44 hourExc Lay Backfill Culvert Pipe Crew 1.00 EA 738.505Foreman 1.0 71.37 3,172Equip Oper Cl 3 (Backhoe) 1.0 73.56 3,269Equip Oper Cl 6 Gradechecker 1.0 70.88 3,150Truck Driver Cl 4 (Water) 0.5 55.70 1,238Laborer 4.0 57.03 10,1392.6 CY Backhoe (Cat 350) 1.0 98.70 4,38730 Ton Compactor 315 hsp (Cat 825) 1.0 140.24 6,2333/4 Ton Pickup Truck 2x2 1.0 11.14 4955000 Gallon Watertanker 0.5 33.29 740Pipe Bedding 44.5 CY 50.00 2,226900 mm (36") x 3.5 mm Corrugated Steel Pipe (68mm x 13mm) 500.0 FT 44.25 22,12517 Rock Anchors 2,440.00 LF 397 22,958 12,309 48,831 84,0980.16 9.41 5.04 20.01 34.47Page 26 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost10 Rock Bolts 2,440.00 LF 397 22,958 12,309 48,831 84,0980.16 9.41 5.04 20.01 34.47Prod=24.56 FT/hour, 0.163MH/FT, 6.14 FT/MH, 99.36 hourDrill Install Rockbolts 1.00 EA 354.94Labor Foreman 1.0 58.03 5,766Laborer 1.0 57.03 5,667Driller 1.0 58.97 5,859Nozzleman 1.0 57.03 5,667Post-tensioning Jack 1.0 4.81 478Grout Pump 1.0 10.52 1,045Grout Plant 1.0 20.96 2,083Motorized Manlift 30 Ft 1.0 13.74 1,365Hydraulic Drill 3" (AC1238/Tam400) 1.0 73.85 7,338Nut Bolt Washer Plate 212.0 EA 10.00 2,120Resin Cartridge 212.0 EA 2.00 424Rockbolt 1-1/2" 2,440.0 FT 18.97 46,28718 Wire Mesh 21,200.00 SF 591 34,285 8,151 20,988 63,4230.03 1.62 0.38 0.99 2.99Prod=143.52 SF/hour, 0.028MH/SF, 35.88 SF/MH, 147.71 hourPin Wire Mesh to Rock off Muckpile 1.00 EA 287.28Labor Foreman 1.0 61.01 9,012Laborer 3.0 57.03 25,272375 CFM Diesel Compressor 1.0 36.56 5,4003/4 Ton Pickup Truck 4x4 1.0 18.62 2,750Draped Mesh 21,200.0 SF 0.99 20,98819 Pipeline Exc & Lay HDPE Pipe 42in 11,910.00 LF 6,312 392,255 233,740 2,224,193 2,850,1870.53 32.93 19.63 186.75 239.31Prod=15.10 FT/hour, 0.530MH/FT, 1.89 FT/MH, 788.99 hourPolyethylene 42in Pipe, Butt Fused 1.00 EA 724.97Backhoe Operator 1.0 77.44 61,099Labor Foreman 1.0 61.01 48,136Laborer 5.0 57.03 224,981Crane Operator Class A 1.0 73.56 58,0382.6 CY Backhoe (Cat 350) 1.0 142.59 112,50260 KW Diesel Generator Set 1.0 20.99 16,5613/4 Ton Pickup Truck 2x2 1.0 11.14 8,78925 Ton Pitman Boom Truck 1.0 53.09 41,88842 in HDPE Pipe 11,910.0 LF 186.75 2,224,193Fusion Machine Rental 4.0 MO 13,500.00 54,00020 Pipeline Bedding 1,450.00 CY 406 24,953 5,673 79,750 110,3760.28 17.21 3.91 55.00 76.12Prod=25.00 CY/hour, 0.280MH/CY, 3.57 CY/MH, 58.00 hourPlace Sand Bedding, per m3 1.00 EA 528.03Truck Driver Cl 4 (Water) 1.0 55.70 3,231General Labor Foreman 1.0 58.00 3,364General Laborer 4.0 61.41 14,247Loader Operator 1.0 70.88 4,1113.5 CY Loader (Cat 950) 1.0 58.84 3,4133/4 Ton Pickup Truck 2x2 1.0 11.14 6463000 Gallon Watertruck 1.0 27.83 1,614Sand Pipe Bedding 1,595.0 CY 50.00 79,75025 Pipeline Select Backfill 1.5 in Minus 10,184.00 CY 2,852 175,254 39,844 560,120 775,2180.28 17.21 3.91 55.00 76.12Prod=25.00 CY/hour, 0.280MH/CY, 3.57 CY/MH, 407.36 hourPlace Select Backfill 1.00 EA 528.03Truck Driver Cl 4 (Water) 1.0 55.70 22,690General Labor Foreman 1.0 58.00 23,627General Laborer 4.0 61.41 100,064Loader Operator 1.0 70.88 28,8743.5 CY Loader (Cat 950) 1.0 58.84 23,9693/4 Ton Pickup Truck 2x2 1.0 11.14 4,5383000 Gallon Watertruck 1.0 27.83 11,337Select backfill 1.5in Minus 11,202.4 CY 50.00 560,120Page 27 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost30 Pipeline Backfill Common 13,925.00 CY 836 54,993 43,234 98,2270.06 3.95 3.10 7.05Prod=50.00 CY/hour, 0.060MH/CY, 16.67 CY/MH, 278.50 hourCommon Backfill 1.00 EA 352.7Equip Oper Cl 3 1.0 70.88 19,740Truck Driver Cl 4 (Water) 1.0 55.70 15,512Loader Operator 1.0 70.88 19,740170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 19,0973.5 CY Loader (Cat 950) 1.0 58.84 16,3873000 Gallon Watertruck 1.0 27.83 7,75140 Gabion Walls 4,000.00 SF 140,000 140,00035.00 35.00Gabion Wall 4,000.0 SF 35.00 140,00096 Outlet Pipe in Reservoir 400.00 LF 724 50,333 34,616 63,500 50,000 20,000 44,000 262,4491.81 125.83 86.54 158.75 125.00 50.00 110.00 656.1210 Freight In & Out Fexifloats 18.00 LDS 54,000 54,0003,000.00 3,000.00Freight Fexifloats 9.0 LDS 6,000.00 54,00030 Assemble Dock & Crane Barge 1.00 LS 304 21,208 10,421 3,500 35,128304.00 21,207.60 10,420.88 3,500.00 35,128.48Prod=1.00 HR/hour, 7.000MH/HR, 0.14 HR/MH, 40.00 hourCrane Barge crew 1.00 EA 679.16Crane Operator Class-A 1.0 70.58 2,823Pile Driving Foreman 1.0 73.04 2,922Pile Driver 3.0 71.04 8,525Pile Driver Helper 1.0 61.00 2,440Oiler 1.0 70.88 2,835100 Ton Crawler Crane (Linkbelt218) 1.0 158.66 6,3461- Ton Mechanic Truck 1.0 31.88 1,275Prod=1.00 HR/hour, 3.000MH/HR, 0.33 HR/MH, 8.00 hourExcavate & Load Backhoe 1.00 EA 557.76Equipment Foreman 1.0 75.00 600Backhoe Operator 1.0 67.40 539Dozer Operator 1.0 65.45 524305 Hsp Bulldozer ( Cat D8 ) 1.0 193.10 1,5452.6 CY Backhoe (Cat 350) 1.0 142.59 1,1411/2 Ton Pickup Truck 4x4 1.0 14.22 114Crane Barge Misc Materials 1.0 LS 3,500.00 3,50031 Mobilize Crane 1.00 LS 6,000 6,0006,000.00 6,000.00Mobilize Crane 1.0 LS 6,000.00 6,00040 Pipeline HDPE Pipe 36in Fuze Pipe 400.00 LF 140 9,581 1,849 50,000 61,4290.35 23.95 4.62 125.00 153.57Prod=20.00 FT/hour, 0.350MH/FT, 2.86 FT/MH, 20.00 hourPolyethylene 900mm (36") Pipe, Butt Fused 1.00 EA 571.46Pipefitter Foreman 1.0 71.14 1,423Pipefitter 3.0 68.11 4,087Pipefitter Helper 2.0 65.00 2,600Crane Operator Class A 1.0 73.56 1,47160 KW Diesel Generator Set 1.0 20.99 420Large Dia. Polyethylene Fusion Machine 1.0 7.21 1443/4 Ton Pickup Truck 2x2 1.0 11.14 22325 Ton Pitman Boom Truck 1.0 53.09 1,06236 in HDPE Pipe 400.0 LF 125.00 50,00045 Set & Anchor Pipe to Lake Bottom 400.00 LF 280 19,545 22,346 20,000 44,000 105,8910.70 48.86 55.87 50.00 110.00 264.73Prod=1.00 HR/hour, 7.000MH/HR, 0.14 HR/MH, 40.00 hourCrane Barge crew 1.00 EA 1047.28Crane Operator Class-A 1.0 70.58 2,823Pile Driving Foreman 1.0 73.04 2,922Pile Driver 3.0 71.04 8,525Pile Driver Helper 1.0 61.00 2,440Oiler 1.0 70.88 2,835100 Ton Crawler Crane (Linkbelt218) 1.0 158.66 6,346250 Hsp Marine Workboat 1.0 175.00 7,00060 x 80 x 7 Crane Barge with anchors, air, lights 1.0 225.00 9,000Concrete Weights 20.0 EA 1,000.00 20,000Divers team 40.0 Hour 1,100.00 44,000Page 28 of 36 Estimate Line DetailStetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency: USD-United States-DollarItemDescription QuantityUOM Rate ManHrs Labor Equip Job Mat Perm Mat Mech Elec Eq Sub/Plug Total Cost97 Energy Dissipation Structure 1.00 LS 40,000 40,00040,000.00 40,000.00Energy Dissipation Structure 1.0 LS 40,000.00 40,000INDIRECTS 1.00 LS 1 484,857 4,538,250 5,023,1071.00 484,857.00 4,538,250.00 5,023,107.0098 Indirects 1.00 LS 1 484,857 1,080,850 1,565,7071.00 484,857.00 1,080,850.00 1,565,707.0010 Indirects 1.00 LS 1,080,850 1,080,8501,080,850.00 1,080,850.0020 Labor Overtime 1.00 LS 1 484,857 484,8571.00 484,857.00 484,857.00Labor Overtime 1.0 EA 484,857.00 1.00 hour99 Contingency 1.00 LS 3,457,400 3,457,4003,457,400.00 3,457,400.00Page 29 of 36 Markup SummaryEstimate: Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity OptionCurrency : USD - United States Dollar Date:1/13/2010General Information:*See BOE AssumptionsLabor Equipment Job Matls Perm Matls Subcontract Allowance % TotalDirect Costs: 3,030,360$ 1,979,371$ 264,988$ 4,197,418$ 1,336,232$ 1$ 87%Indirect Costs: 484,857$ -$ -$ -$ -$ 1,080,850$ 13%Subtotal (D + I): 3,515,200$ 11,979,400$ 2265,000$ 34,197,400$ 41,336,200$ 51,080,900$ 6100%Grand Total (1-6): 12,374,100$ 7-$ 80.00% Materials Sales Tax on Job Materials & Permanent Materials (% of 3, 4))26,700$ 92.00% Subcontractor Bonds (% of 5)186,000$ 101.50% Contractor Insurance Program (% of 7-9)106,900$ 118.00% General Contractor Markup On Subcontractors (% of 5)32%1,135,800$ 1210.00% General Contractor H/O OH&P (% of all less subs)-$ 130.00% Market Conditions / Owner Special Contractual Requirements (% of 7-12)3,457,400$ 1425.00%Estimating Accuracy / Scope Contingency (% of 7-13) 4.00-$ 150.00% Escalation Allowance to Estimated MPC (% of 7-14) Sub Total: 17,286,900$ 1639.70% Estimated Contractor's Bid (-10% to +15%)14,690,000$ 1715.0%Low Range (AACE)21,610,000$ 1825.00%High Range (AACE)MWH OPCC Disclaimer – Any opinions of probable construction costs (“OPCC”) prepared by MWH, including evaluations of Client’s project budget, represent MWH’s best judgment as a design professional familiar with the construction industry. Unless and to the extent otherwise indicated by MWH, such opinions or evaluations are based upon current market rates for labor, materials and equipment. The Client acknowledges that MWH has no control over the costs of labor, materials or equipment, construction contractor’s methods of determining bid prices, competitive bidding environments, unidentified field conditions, market conditions, inflation or any other factors that may affect the OPCC, the project budget or negotiating conditions at the time of execution of the construction contract. Furthermore, this OPCC is based on stable market conditions that exhibit predictable supply/demand relationships and does not attempt to capture the impacts of hyper-inflationary or deflationary market cycles. Client further acknowledges that the OPCC is a "snapshot in time" and that the reliability of the OPCC will degrade over time. Accordingly, MWH cannot and does not warrant or represent that construction bids or negotiated construction prices will not vary from Client’s project budget or MWH's good faith Class 4 OPCC.AACE International CLASS 4 Cost Estimate – Class 4 estimates are generally prepared based on limited information and subsequently have fairly wide accuracy ranges. Typically, engineering is 10% to 40% complete. They are typically used for project screening, determination of feasibility, concept evaluation, and preliminary budget approval. Virtually all Class 4 estimates use stochastic estimating methods such as cost curves, capacity factors, and other parametric and modeling techniques. Expected accuracy ranges are from –15% to –30% on the low side and +20% to 50% on the high side, depending on the technological complexity of the project, appropriate reference information, and the inclusion of an appropriate contingency determination. Ranges could exceed those shown in unusual circumstances.(AACE International Recommended Practices and Standards). Page 30 of 36 Labor Hour Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Labor Classification & Description Code Description Labor Hours Rate Total Cost 0 Other MWH3 Foreman 2,115.96 71.37 151,016.33 MWH5 Equip Oper Cl 3 278.50 70.88 19,740.08 MWH5 Equip Oper Cl 3 (Backhoe) 1,911.06 73.56 140,577.84 MWH5 Equip Oper Cl 3 (Dozer) 2,346.11 70.88 166,291.98 MWH5 Equip Oper Cl 3 (Grader) 1,123.92 70.88 79,663.39 MWH5 Equip Oper Cl 3 (Loader) 259.39 70.88 18,385.33 MWH5 Equip Oper Cl 3 Grader) 674.77 70.88 47,827.93 MWH6 Equip Oper Cl 4 (Gradechecker) 164.90 70.88 11,688.11 MWH6 Equip Oper Cl 4 (Roller) 839.67 70.88 59,516.05 MWH8 Equip Oper Cl 7 Art truck 6,428.93 70.88 455,682.57 MWH9 Equip Oper Cl 6 Gradechecker 1,691.68 70.88 119,906.06 MWH38 Labor Cl 5 (Pipe) 986.11 57.03 56,237.66 MWH43 Truck Driver Cl 4 (Water) 2,811.88 55.70 156,621.80 Sub-Total 21,632.88 1,483,155.14 3100 Formsetters FS Formsetter 37.20 65.60 2,440.58 Sub-Total 37.20 2,440.58 30000 Labourers Heavy120 Pusher 72.94 75.00 5,470.40 Heavy200 Powderman 104.17 62.13 6,472.36 Heavy210 Driller 208.35 62.13 12,944.72 Concrete100 Concrete Foreman 179.40 71.11 12,756.94 Concrete300 Concrete Labourer 674.28 57.03 38,454.39 Concrete400 Vibrator Operator 118.79 61.41 7,295.18 Concrete500 Concrete Truck Spotter 59.40 61.41 3,647.59 Road150 Foreman Roadwork 202.40 71.11 14,392.66 Road410 Skilled Labourer Roadwork 305.82 57.03 17,441.02 Road420 Labourer Roadwork 404.80 57.03 23,085.74 Road620 Spotter 339.54 57.03 19,364.00 General100 General Labour Foreman 569.53 58.00 33,033.00 General300 General Labourer 3,013.72 61.41 185,072.70 General410 Helper 214.63 59.64 12,801.05 Sub-Total 6,467.78 392,231.76 31000 Formsetters Form120 Formsetter Foreman 474.22 66.60 31,583.25 Form300 Formsetter 2,150.52 65.60 141,073.80 Form400 Formsetter Helper 990.82 61.41 60,846.40 Sub-Total 3,615.56 233,503.45 32000 Rodmen Rebar100 Rodman Foreman 226.90 66.52 15,093.52 Rebar200 Rodman 907.61 65.52 59,466.49 Rebar300 Rodman Helper 310.25 61.41 19,052.50 Sub-Total 1,444.76 93,612.51 33500 Cement Finishers Cement200 Cement Finisher 276.08 61.93 17,097.45 Sub-Total 276.08 17,097.45 50000 Iron & Steel Workers Iron100 Ironworker Foreman 2.17 66.52 144.25 Iron200 Ironworker 17.35 65.52 1,136.62 Sub-Total 19.52 1,280.87 Page 31 of 36 Labor Hour Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Labor Classification & Description Code Description Labor Hours Rate Total Cost 200000 Equipment Operators Operator010 Equipment Foreman 347.54 75.00 26,065.54 Crane110 Crane Operator Class-A 80.00 70.58 5,646.40 Backhoe100 Backhoe Operator 796.99 77.34 61,638.63 Dozer100 Dozer Operator 190.40 70.65 13,452.11 Packer100 Packer Operator 101.86 72.50 7,385.24 Sub-Total 1,516.79 114,187.92 210000 Pipefitters Pipefitter100 Pipefitter Foreman 20.00 71.14 1,422.80 Pipefitter200 Pipefitter 60.00 68.11 4,086.60 Pipefitter300 Pipefitter Helper 40.00 65.00 2,600.00 Sub-Total 120.00 8,109.40 300000 Labourers Labour110 Labour Foreman 1,036.07 60.72 62,914.32 Labour130 Labor Overtime 1.00 484,857.00 484,857.00 Labour130 Labourer 4,665.24 57.03 266,058.39 Driller210 Driller 99.36 58.97 5,859.34 Nozzle110 Nozzleman 99.36 57.03 5,666.58 Pile500 Pile Driving Foreman 80.00 73.04 5,843.20 Pile510 Pile Driver 240.00 71.04 17,049.60 Pile520 Pile Driver Helper 80.00 61.00 4,880.00 Sub-Total 6,301.03 853,128.44 312300 Equipment Operators Operator010 Equipment Foreman 40.62 75.00 3,046.45 Operator200 Crane Operator Class A 971.00 73.56 71,426.63 Operator310 Backhoe Operator 949.97 73.56 69,879.93 Operator410 Loader Operator 896.77 70.88 63,563.12 Operator420 Dozer Operator 40.62 70.88 2,879.10 Operator730 Concrete Pump Operator 179.40 70.88 12,715.68 Sub-Total 3,078.38 223,510.91 312350 Truck Drivers Truck310 Truck Driver 185.41 63.37 11,749.64 Sub-Total 185.41 11,749.64 335000 Welders Welder200 Welder 7.60 66.98 509.05 Sub-Total 7.60 509.05 580000 Mechanics Mechanic510 Mechanics Helper 52.09 65.00 3,385.67 Mechanic520 Oiler 92.71 70.88 6,571.05 Sub-Total 144.79 9,956.72 600000 Carpenters Carpenter100 Carpenter Foreman 7.60 66.60 506.16 Carpenter200 Carpenter 7.60 65.60 498.56 Sub-Total 15.20 1,004.72 3000000 Truck Drivers Water307 Water Truck Driver 174.82 56.95 9,956.17 OffHwy100 Off Hwy Truck Driver 853.90 63.37 54,111.85 Sub-Total 1,028.73 64,068.02 4000000 Mechanics Mechanic520 Oiler 80.00 70.88 5,670.40 Sub-Total 80.00 5,670.40 Totals:45,971.71 3,515,216.96 Page 32 of 36 Equipment Hour Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Equipment Classification & Description Code Description Equip Hours Average Rate Total Cost 810000 Earthmoving Equipment D6 170 Hsp Bulldozer ( Cat D6 ) 2,807.01 70.24 197,169.54 D8 305 Hsp Bulldozer ( Cat D8 ) 48.62 146.03 7,099.90 IT28 2.0 CY Loader (CAT IT28) 152.91 38.33 5,861.08 950 3.5 CY Loader (Cat 950) 1,003.25 58.84 59,031.03 14G 200 Hsp Grader (Cat 14G) 1,798.69 87.75 157,835.27 790 1.7 CY Backhoe ( JD 790 ) 52.09 68.92 3,589.85 330 2.0 CY Backhoe ( Cat 330 ) 305.82 80.43 24,597.25 350 2.6 CY Backhoe (Cat 350) 3,088.21 114.85 354,689.08 680 1.7 CY Backhoe Loader (Case680) 211.90 35.51 7,524.67 Tandem20Ton 20 Ton (10 CY) Tandem Truck 40.62 38.17 1,550.44 Tandem20Ton 20 Ton (10 CY) Tandem Truck-Operated 305.82 47.78 14,612.17 Articulated300 30 Ton Articulated Truck (Cat D300) 7,108.01 93.70 666,011.99 TAT10Ton 10 Ton All Terrain Vehicle ( Nodwell 110 ) 40.62 81.61 3,314.95 JumpJack20 Jumping Jack Handheld Packer 233.67 4.12 962.71 Compactor22I 22" Smooth Drum Manual (Bomag 55) 9.50 5.65 53.69 Compactor24I 24" Smooth Drum Manual (Bomag 60) 233.67 6.41 1,497.80 Compactor8To8 Ton Compactor 66" (Cat 433) 174.82 46.37 8,106.50 Compactor15T15 Ton Compactor 84" (Cat 563) 164.90 47.13 7,771.74 Compactor30T30 Ton Compactor 315 hsp (Cat 825) 719.22 140.24 100,863.10 Sub-Total 18,499.35 1,622,142.77 820000 Paving Equipment Trowel10 Concrete Power Trowel-Walker 0.31 3.34 1.04 Sub-Total 0.31 1.04 840000 Concrete Equipment ConcretePump124 YPH Trailer Mounted Concrete Pump 179.40 65.75 11,795.37 Bucket2CY 2-CY Concrete Bucket (Gravity) 40.38 0.62 25.04 VibratorNorma Concrete Vibrator-Normal 358.79 0.54 193.75 Jack110 Post-tensioning Jack 99.36 4.81 477.93 GroutPump10 Grout Pump 99.36 10.52 1,045.28 GroutPlant10 Grout Plant 99.36 20.96 2,082.62 Sub-Total 876.66 15,619.98 850000 Utility Equipment Generator10kw10 KW Generator Set (Gas) 366.39 4.93 1,806.33 Generator60kw60 KW Diesel Generator Set 808.99 20.99 16,980.71 Compressor15150 CFM Diesel Compressor 6.28 11.58 72.71 Compressor37375 CFM Diesel Compressor 147.71 36.56 5,400.45 WeldD250Amp250 Amp Diesel Welder 11.94 4.75 56.70 FusionWelder2Large Dia. Polyethylene Fusion Machine 20.00 7.21 144.20 CuttingTorch1 Acetylene Cutting Torch 11.94 2.24 26.74 Sub-Total 1,373.25 24,487.83 860000 Hoisting Equipment TruckCrane20 20 Ton Truck Crane 41.67 58.07 2,420.03 TruckCrane40 40 Ton Truck Crane 8.98 88.68 796.35 CrawlerCrane1100 Ton Crawler Crane (Linkbelt218) 80.00 158.66 12,692.80 HydraulicCran 20 Ton Hydraulic Crane (Grove58) 1.08 45.15 48.95 HydraulicCran 40 Ton Hydraulic Crane (Grove700) 95.80 78.34 7,504.85 Forklift4 4 Tonne Forklift (JCB-8000lb) 41.67 17.19 716.38 Manlift30 Motorized Manlift 30 Ft 99.36 13.74 1,365.23 Sub-Total 368.57 25,544.58 Page 33 of 36 Equipment Hour Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Equipment Classification & Description Code Description Equip Hours Average Rate Total Cost 870000 Foundation & Marine Equipment MarineWorkbo 250 Hsp Marine Workboat 40.00 175.00 7,000.00 Barge 60 x 80 x 7 Crane Barge with anchors, air, lights 40.00 225.00 9,000.00 Sub-Total 80.00 16,000.00 880000 Drilling & Tunneling Equipment DrillHyd3 Hydraulic Drill 3" (AC1238/Tam400) 307.71 73.85 22,724.41 CoreDrill10 Diamond Core Drill (Hilti) 7.60 7.17 54.49 Sub-Total 315.31 22,778.91 890000 Service & Maintenance Equipment Pickup30 1/2 Ton Pickup Truck 2x2 202.77 8.83 1,790.48 Pickup35 1/2 Ton Pickup Truck 4x4 8.00 14.22 113.76 Pickup50 3/4 Ton Pickup Truck 2x2 3,483.02 11.14 38,800.85 Pickup60 3/4 Ton Pickup Truck 4x4 147.71 18.62 2,750.45 Pickup70 3/4 Ton Crew Cab Truck 484.33 11.34 5,492.35 Flatbed5 5 Ton Flat Bed Truck 552.96 17.67 9,770.82 Mechanic1 1- Ton Mechanic Truck 40.00 31.88 1,275.20 Water20 3000 Gallon Watertruck 1,152.35 30.19 34,786.60 Water30 5000 Gallon Watertanker 1,834.35 33.29 61,065.67 Boomtruck25 25 Ton Pitman Boom Truck 808.99 53.09 42,949.31 Sub-Total 8,714.50 198,795.50 Totals:30,227.95 1,925,370.61 General Costs EQUIP Fusion Machine Rental N/A N/A 54,000.00 Sub-Total 54,000.00 Totals:30,227.95 1,979,370.61 Page 34 of 36 Material Quantity Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Material Classification & Description Code Description Quantity UOM Rate Total Cost 0 Other MAT 36 in HDPE Pipe 400.00 LF 125.00 50,000.00 MAT 36in Steel Pipe 536.00 LF 350.00 187,600.00 MAT 42 in HDPE Pipe 11,910.00 LF 186.75 2,224,192.50 MAT Access Road Pipe 2,000.00 LF 37.00 74,000.00 MAT Bedding 4.40 CY 50.00 220.00 MAT Concrete Weights 20.00 EA 1,000.00 20,000.00 MAT Cure 5,315.00 SF 0.10 531.50 MAT Cure materials 3,850.00 SF 0.10 385.00 MAT Dam Embankment Drainage Blanket 3,903.00 CY 50.00 195,150.00 MAT Fabric 3,333.00 SY 9.00 29,997.00 MAT Form Supplies 3,050.00 SF 1.00 3,050.00 MAT Form supply 5,597.76 SF 1.00 5,597.76 MAT Freight Fexifloats 9.00 LDS 6,000.00 54,000.00 MAT Mobilize Crane 1.00 LS 6,000.00 6,000.00 MAT Pipe Bedding 158.73 CY 50.00 7,936.49 MAT Riprap 30.00 TN 45.00 1,350.00 MAT Road Base Gravel 3,615.00 CY 50.00 180,750.00 MAT Sand Pipe Bedding 1,595.00 CY 50.00 79,750.00 MAT Select backfill 1.5in Minus 11,202.40 CY 50.00 560,120.00 ROCK BOLT Nut Bolt Washer Plate 212.00 EA 10.00 2,120.00 ROCK BOLT Resin Cartridge 212.00 EA 2.00 424.00 Sub-Total 56,954.29 3,683,174.25 100000 Indirect Items MAT Crane Barge Misc Materials 1.00 LS 3,500.00 3,500.00 Sub-Total 1.00 3,500.00 310000 Formwork FormSupply11Supply Light Wood Form 518.95 sf 5.09 2,641.44 FormSupply11Supply Wood Form Wood Walers & Strongbacks 1,000.00 SF 5.56 5,560.00 FormSupply13Supply Symons Versiform 4,067.63 sf 15.57 63,332.97 FormSupply13Supply Circular Steel Form 750.00 SF 51.13 38,347.50 Sub-Total 6,336.58 109,881.92 320000 Reinforcement Rebar11130 A Supply Rebar 250,046.05 lb 0.75 187,534.54 Sub-Total 250,046.05 187,534.54 331000 Ready Mix Concrete Readymix21134000 PSI (30MPA) Readymix Concrete 903.66 CY 160.00 144,586.11 Readymix21144,000 PSI (30 MPA) Readymix Concrete 670.73 cy 160.00 107,316.63 Sub-Total 1,574.39 251,902.74 336000 Concrete Accessories Waterstop61029" Waterstop 446.45 ft 7.35 3,281.39 Sub-Total 446.45 3,281.39 370000 Falsework Jack10020 Jacks for shoring 257.76 sf 0.50 128.88 Sub-Total 257.76 128.88 550000 Metal Fabrications MATL Galv Steel Rail 1.5in 60.00 FT 54.00 3,240.00 MATL Steel Grating 264.00 SF 25.00 6,600.00 Sub-Total 324.00 9,840.00 3125000 Erosion Control Riprap110 9" Riprap (250mm) 4,000.00 TN 12.65 50,600.00 SiltFence130 Heavy Duty Silt Fence 30,000.00 FT 0.55 16,500.00 Sediment110 Straw Bales 500.00 EA 3.98 1,990.00 Sediment120 Stakes for Straw Bales (2" x 2" x 4 ft) 500.00 EA 1.00 500.00 Sub-Total 35,000.00 69,590.00 3133000 Rock Stabilization ROCK BOLT Rockbolt 1-1/2" 2,440.00 FT 18.97 46,286.80 Mesh340 Draped Mesh 21,200.00 SF 0.99 20,988.00 Sub-Total 23,640.00 67,274.80 3139000 Rock Excavation DrillSteel130 Drill Bits & Steel (65mm) 2-1/2 inch 13,680.00 FT 0.72 9,849.60 Explosive1320Ammonium Nitrate Fuel Oil 13,680.00 LB 0.50 6,840.00 Detonator1410Electric Blasting Caps 13,680.00 EA 2.74 37,483.20 Sub-Total 41,040.00 54,172.80 3342000 Culverts CSP900x3.5 900 mm (36") x 3.5 mm Corrugated Steel Pipe (68m 500.00 FT 44.25 22,125.00 Sub-Total 500.00 22,125.00 Totals:4,462,406.31 Page 35 of 36 Subcontract Quantity Summary Stetson Creek Diversion and Cooper Lake Dam Facilities - Gravity Option Currency: USD-United States-Dollar Subcontract Classification & Description Code Description Quantity UOM Rate Total Cost 14000 Site Services INST Instrumentation (Flow Meters & Gauges) 1.00 LS 210,000.00 210,000.00 Mob Mobilization 1.00 LS 350,000.00 350,000.00 Sub-Total 560,000.00 51200 Structural Steel Cross Stream Crossings 2.00 EA 10,000.00 20,000.00 Steel320 Bridge 1.00 LS 225,000.00 225,000.00 Steel320 Outlet Gates 36in 2.00 EA 25,000.00 50,000.00 Steel320 Sluice Gate 30in 1.00 EA 36,000.00 36,000.00 Steel320 Sluice Gate 48in 1.00 EA 50,000.00 50,000.00 Steel320 Trashrack 1.00 EA 25,000.00 25,000.00 Steel320 Trashrack 1.00 LS 35,000.00 35,000.00 STR Maintenance Building 80.00 SF 250.00 20,000.00 Sub-Total 461,000.00 54500 Supply Detail & Fab Steel Bldgs Bldg140 Energy Dissipation Structure 1.00 LS 40,000.00 40,000.00 Sub-Total 40,000.00 312000 Removals Sub Divers team 40.00 Hour 1,100.00 44,000.00 Sub-Total 44,000.00 323200 Earth Walls BinWall10 Gabion Wall 4,000.00 SF 35.00 140,000.00 Sub-Total 140,000.00 329000 Landscaping Seed110 Seeding & Wood Fiber Mulch 20.00 AC 4,000.00 80,000.00 Sub-Total 80,000.00 335000 Pipeline Drill & Shoot Drill & Shoot 711.00 CY 12.00 8,532.00 Weld Weld 36in Pipe 15.00 JTS 180.00 2,700.00 Sub-Total 11,232.00 Total:1,336,232.00 Page 36 of 36 APPENDIX B2 2011 OPCC Siphon Option (excerpt) Markup Summary Report Estimated Assumed Schedule:na Estimate:STETSON CREEK DIVERSION UPDATE Estimated Date of NTP:na Currency : USD United States Dollar Date:3/16/2011 General Information: Labor Equipment Job Matls Perm Matls Subcontract Allowance Total Direct Costs: 2,206,418 1,145,079 318,964 4,150,140 1,038,532 8,859,133 Indirect Costs: 375,091 923,422 1,298,513 Subtotal:2,581,509 1 1,145,079 2 318,964 3 4,150,140 4 1,038,532 5 923,422 6 10,157,646 7 Running Total: 10,157,600 7 8 0.00% 9 0.00% 20,800 10 2.00% 152,700 11 1.50% 83,100 12 8.00% % of Labor 39%929,300 13 10.00% 14 0.00% Materials Sales Tax on Permanent Materials (% of 4) Materials Sales Tax on Temporary Job Materials (% of 3) Subcontractor Bonds (% of 5) Contractor Insurance Program (% of 7 10) General Contractor Markup On Subcontractors (% of 5) General Contractor H/O OH&P (% of 7 thru 11 minus 5) Market Conditions / Owner Reputation / Special Requirements (% of 7 13) S3-Markup/STETSON CREEK MARCH 2011 OPCC COST REPORT.xlsx 2,835,900 15 25.00% 8.20 yrs 16 0.00% Grand Total: 14,179,400 39.59% AACE Accuracy Range 12,760,000 17,720,000 10.00% +25.00% General Notes: 1) 2) 3) 4) AACE International CLASS 4 Cost Estimate – Class 4 estimates are generally prepared based on limited information and subsequently have fairly wide accuracy ranges. Typically, engineering is 10% to 40% complete. They are typically used for project screening, determination of feasibility, concept evaluation, and preliminary budget approval. Virtually all Class 4 estimates use stochastic estimating methods such as cost curves, capacity factors, and other parametric and modeling techniques. Expected accuracy ranges are from –15% to –30% on the low side and +20% to 50% on the high side, depending on the technological complexity of the project, appropriate reference information, and the inclusion of an appropriate contingency determination. Ranges could exceed those shown in unusual circumstances.(AACE International Recommended Practices and Standards). MWH OPCC Disclaimer – Any opinions of probable construction costs (“OPCC”) prepared by MWH, including evaluations of Client’s project budget, represent MWH’s best judgment asa design professional familiar with the construction industry. Unless and to the extent otherwise indicated by MWH, such opinions or evaluations are based upon current market rates for labor, materials and equipment. The Client acknowledges that MWH has no control over the costsof labor, materialsor equipment, construction contractor’s methods of determining bid prices, competitive bidding environments, unidentified field conditions, market conditions, inflation or any other factors that may affect the OPCC, the project budget or negotiating conditions at the time of execution of the construction contract. Furthermore, this OPCC is based on stable market conditions that exhibit predictable supply/demand relationships and does not attempt to capture the impacts of hyper inflationary or deflationary market cycles. Client further acknowledges that the OPCC is a "snapshot in time" and that the reliability of the OPCC will degrade over time. Accordingly, MWH cannot and does not warrant or represent that construction bids or negotiated construction prices will not vary from Client’s project budget or MWH's good faith Class _ OPCC Estimating Accuracy / Scope Contingency (% of 7 14) Escalation Allowance to Estimated MPC (% of 7 15) Estimated Contractor's Bid (10% to +15%) S3-Markup/STETSON CREEK MARCH 2011 OPCC COST REPORT.xlsx Bid Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Grand Total Price: 14,179,451 Tax (%) 0.00 0 Total Price 14,179,451 Total Markup 1,185,905 Markup (%) 11.67 0 Total Construction Cost 12,993,546 Total Indirect Costs (I) 12.78 4,134,413 Total Direct Costs (D) 87.22 8,859,133 Item Description Quantity UOM Unit Cost Total Cost DIRECTS SIPHON 1.00 LS 8,859,132.80 8,859,133 Mobilization 1.00 LS 350,000.00 350,000 D 10 Mobilization 1.00 LS 350,000.00 350,000 Main Access Road 1.00 LS 492,612.58 492,613 D 15 Main Access Road 4.50 Mile 109,469.46 492,613 Erosion Control & Restoration 1.00 LS 306,896.70 306,897 D 30 Erosion Control 1.00 LS 226,896.70 226,897 D 35 Restoration 20.00 AC 4,000.00 80,000 Spillway Excavation & Backfill for Pipe 1.00 LS 1,036,695.53 1,036,696 D 40 Spillway Excavation & Embankment 10,850.00 CY 32.04 347,667 D 41 Concrete Cut Off 52.00 CY 208.71 10,853 D 42 Concrete Encase Pipeline 378.00 CY 208.71 78,893 D 42 Concrete Slab Spillway 1,240.00 CY 421.02 522,068 D 43 30 in Bell & Sp Steel Pipe 775.00 LF 99.63 77,214 Inlet/Outlet & Siphon Pipe 1.00 LS 284,391.26 284,391 D 17 Inlet Outlet Channel Excavation 3,800.00 CY 9.06 34,443 D 60 Outlet 1.00 LS 58,304.21 58,304 5/29 ,, D 63 Exc Lay Backfill 30in Bell & SP Steel Pipe 725.00 LF 193.77 140,486 D 65 Riprap Outlet 250.00 CY 204.63 51,158 Intake 1.00 LS 77,568.83 77,569 D 70 Intake 1.00 LS 77,568.83 77,569 Stetson Creek Diversion 1.00 LS 778,763.42 778,763 D 85 Diversion Dam Stetson Creek 1.00 LS 778,763.42 778,763 Instrumentation 1.00 LS 210,000.00 210,000 D 86 Instrumentation ( Flow Meters & Guages) 1.00 LS 210,000.00 210,000 Stetson Creek Pipeline 1.00 LS 5,322,204.49 5,322,204 D 92 Clearing 15.00 AC 5,329.69 79,945 D 95 Pipeline 11,910.00 LF 414.78 4,940,004 D 96 Outlet Pipe in Reservoir 400.00 LF 655.64 262,256 D 97 Energy Dissapation Structure 1.00 LS 40,000.00 40,000 INDIRECTS 1.00 LS 1,298,513.00 4,134,413 D 99 Contingency 1.00 LS 2,835,900.00 2,835,900 I 98 Indirects 1.00 LS 1,298,513.00 1,298,513 5/29 Item Cost Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Item Description Quantity UOM ManHr Labor Equip Job Mat Perm Mat Sub/Plug Total Cost DIRECTS SIPHON Mobilization 10 Mobilization 1.00 LS 350,000 350,000 350,000.00 350,000.00 Section (Mobilization) Totals:1.00 LS 0 0 0 350,000 350,000 0.00 0.00 0.00 0.00 0.00 350,000.00 350,000.00 Main Access Road 15 Main Access Road 4.50 Mile 2,271 150,830 67,032 254,750 20,000 492,613 504.67 33,517.86 14,896.05 56,611.11 4,444.44 109,469.46 Section (Main Access Road) Totals:1.00 LS 2,271 150,830 67,032 254,750 20,000 492,613 2,271.03 150,830.37 67,032.21 0.00 254,750.00 20,000.00 492,612.58 Erosion Control & Restoration 30 Erosion Control 1.00 LS 1,574 103,262 54,045 69,590 226,897 1,574.15 103,261.78 54,044.91 69,590.00 226,896.70 35 Restoration 20.00 AC 80,000 80,000 4,000.00 4,000.00 Section (Erosion Control & Restoration) Totals:1.00 LS 1,574 103,262 54,045 69,590 80,000 306,897 1,574.15 103,261.78 54,044.91 69,590.00 0.00 80,000.00 306,896.70 Spillway Excavation & Backfill for Pipe 40 Spillway Excavation & Embankment 10,850.00 CY 2,514 165,903 113,798 67,966 347,667 0.23 15.29 10.49 6.26 32.04 41 Concrete Cut Off 52.00 CY 30 1,863 254 8,736 10,853 0.57 35.83 4.89 168.00 208.71 42 Concrete Encase Pipeline 378.00 CY 217 13,542 1,847 63,504 78,893 0.57 35.83 4.89 168.00 208.710 5 35 83 89 68 00 08 42 Concrete Slab Spillway 1,240.00 CY 2,473 159,535 13,993 348,540 522,068 1.99 128.66 11.28 281.08 421.02 43 30 in Bell & Sp Steel Pipe 775.00 LF 233 14,833 4,256 58,125 77,214 0.30 19.14 5.49 75.00 99.63 Section (Spillway Excavation & Backfill for Pipe) Totals:1.00 LS 5,466 355,676 134,148 67,966 478,905 0 1,036,696 5,466.48 355,676.11 134,148.42 67,966.00 478,905.00 0.00 1,036,695.53 Inlet/Outlet & Siphon Pipe 17 Inlet Outlet Channel Excavation 3,800.00 CY 254 17,628 16,815 34,443 0.07 4.64 4.43 9.06 60 Outlet 1.00 LS 186 12,651 1,154 3,564 40,935 58,304 186.04 12,651.36 1,154.24 3,564.00 40,934.61 58,304.21 63 Exc Lay Backfill 30in Bell & SP Steel Pipe 725.00 LF 725 46,562 15,349 78,575 140,486 1.00 64.22 21.17 108.38 193.77 65 Riprap Outlet 250.00 CY 250 16,558 8,434 26,167 51,158 1.00 66.23 33.74 104.67 204.63 Section (Inlet/Outlet & Siphon Pipe) Totals:1.00 LS 1,415 93,398 41,753 3,564 145,676 0 284,391 1,415.34 93,398.45 41,752.54 3,564.00 145,676.27 0.00 284,391.26 Intake 70 Intake 1.00 LS 189 12,708 1,225 2,323 26,313 35,000 77,569 188.70 12,707.53 1,224.85 2,323.17 26,313.29 35,000.00 77,568.83 Section (Intake) Totals:1.00 LS 189 12,708 1,225 2,323 26,313 35,000 77,569 188.70 12,707.53 1,224.85 2,323.17 26,313.29 35,000.00 77,568.83 Stetson Creek Diversion 85 Diversion Dam Stetson Creek 1.00 LS 4,444 287,935 39,288 56,177 275,832 119,532 778,763 4,444.16 287,934.58 39,287.98 56,177.14 275,831.73 119,532.00 778,763.42 Section (Stetson Creek Diversion) Totals:1.00 LS 4,444 287,935 39,288 56,177 275,832 119,532 778,763 4,444.16 287,934.58 39,287.98 56,177.14 275,831.73 119,532.00 778,763.42 6/29 Item Cost Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Item Description Quantity UOM ManHr Labor Equip Job Mat Perm Mat Sub/Plug Total Cost Instrumentation 86 Instrumentation ( Flow Meters & Guages)1.00 LS 210,000 210,000 210,000.00 210,000.00 Section (Instrumentation) Totals:1.00 LS 0 0 0 210,000 210,000 0.00 0.00 0.00 0.00 0.00 210,000.00 210,000.00 Stetson Creek Pipeline 92 Clearing 15.00 AC 1,044 65,201 14,745 79,945 69.61 4,346.71 982.98 5,329.69 95 Pipeline 11,910.00 LF 16,989 1,087,269 758,228 55,843 2,898,663 140,000 4,940,004 1.43 91.29 63.66 4.69 243.38 11.75 414.78 96 Outlet Pipe in Reservoir 400.00 LF 724 50,140 34,616 63,500 70,000 44,000 262,256 1.81 125.35 86.54 158.75 175.00 110.00 655.64 97 Energy Dissapation Structure 1.00 LS 40,000 40,000 40,000.00 40,000.00 Section (Stetson Creek Pipeline) Totals:1.00 LS 18,757 1,202,609 807,588 119,343 2,968,663 224,000 5,322,204 18,757.41 1,202,609.27 807,588.47 119,343.39 2,968,663.36 224,000.00 5,322,204.49 Section (DIRECTS SIPHON) Totals:1.00 LS 34,117 2,206,418 1,145,079 318,964 4,150,140 1,038,532 8,859,133 34,117.29 2,206,418.08 1,145,079.38 318,963.69 4,150,139.65 1,038,532.00 8,859,132.80 INDIRECTS 98 Indirects 1.00 LS 1 375,091 923,422 1,298,513 1.00 375,091.00 923,422.00 1,298,513.00 99 Contingency 1.00 LS 2,835,900 2,835,900 2,835,900.00 2,835,900.00 Section (INDIRECTS) Totals:1.00 LS 1 375,091 0 3,759,322 4,134,413 1.00 375,091.00 0.00 0.00 0.00 3,759,322.00 4,134,413.00 Grand Totals:1 00 LS 34 118 2 581 509 1 145 079 318 964 4 150 140 4 797 854 12 993 546GrandTotals:1.00 LS 34,118 2,581,509 1,145,079 318,964 4,150,140 4,797,854 12,993,546 2,581,509.08 1,145,079.38 318,963.69 4,150,139.65 4,797,854.00 12,993,545.80 7/29 Activity Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Item Description Quantity UOM Unit Cost Total Cost DIRECTS SIPHON 1.00 LS 8,859,132.80 8,859,132.80 Mobilization 1.00 LS 350,000.00 350,000.00 10 Mobilization 1.00 LS 350,000.00 350,000.00 10 Mobilization 1.00 LS 350,000.00 350,000.00 Main Access Road 1.00 LS 492,612.58 492,612.58 15 Main Access Road 4.50 Mile 109,469.46 492,612.58 10 Main Access Road Clearing 3.30 AC 2,082.28 6,871.52 15 Access Road Grading 42,240.00 SY 1.75 74,003.07 20 Access Road Drainage 2,000.00 LF 97.50 194,996.67 25 Access Road Gravel Surfacing 3,615.00 CY 54.42 196,741.31 30 Access Road Stream Crossings 2.00 EA 10,000.00 20,000.00 Erosion Control & Restoration 1.00 LS 306,896.70 306,896.70 30 Erosion Control 1.00 LS 226,896.70 226,896.70 35 Restoration 20.00 AC 4,000.00 80,000.00 Spillway Excavation & Backfill for Pipe 1.00 LS 1,036,695.53 1,036,695.53 40 Spillway Excavation & Embankment 10,850.00 CY 32.04 347,667.25 10 Drill & Shoot 10,850.00 CY 11.21 121,581.71 12 Spillway Rock Excavation 10,850.00 CY 9.03 97,967.54 15 Backfill 9,222.50 CY 11.18 103,118.00 25 Tempory Shoreing 1.36 LS 18,433.18 25,000.00 41 Concrete Cut Off 52.00 CY 208.71 10,852.99 25 Place Concrete 52.00 CY 208.71 10,852.99 42 Concrete Encase Pipeline 378.00 CY 208.71 78,892.86 25 Place Concrete 378.00 CY 208.71 78,892.86 42 Concrete Slab Spillway 1,240.00 CY 421.02 522,068.02 10 Foundation Preparation 16,275.00 SF 1.26 20,512.30 11 Reinforcement 186,000.00 LB 1.16 215,865.02 12 Place Concrete 1,240.00 CY 220.19 273,037.90 14 Fi i h C t B Sl b 16 275 00 SF 0 52 8 412 4014 Finish Concrete Base Slab 16,275.00 SF 0.52 8,412.40 16 Cure Concrete 1,240.00 CY 3.42 4,240.40 43 30 in Bell & Sp Steel Pipe 775.00 LF 99.63 77,214.41 Inlet/Outlet & Siphon Pipe 1.00 LS 284,391.26 284,391.26 17 Inlet Outlet Channel Excavation 3,800.00 CY 9.06 34,443.03 60 Outlet 1.00 LS 58,304.21 58,304.21 10 Outlet Structure Concrete 16.00 CY 1,218.91 19,502.51 10 Outlet Concrete 16.00 CY 1,218.91 19,502.51 10 Foundation Prep 154.00 SF 0.24 37.15 15 Build Base Slab Forms 50.00 SF 14.88 744.13 20 SSM Base Slab Forms 50.00 SF 18.15 907.61 25 Place Conrete Base Slab 6.00 CY 208.71 1,252.27 30 Finish Concrete Base Slab 154.00 SF 0.52 79.60 35 Cure Concrete Base Slab 204.00 SF 0.29 58.90 40 Build Wall Forms 200.00 SF 28.21 5,641.77 45 SSM Wall Forms 400.00 SF 9.21 3,683.00 50 Joint Prep on Slab 50.00 SF 0.91 45.33 55 Place Concrete Wall 10.00 CY 208.75 2,087.51 60 Finish Concrete Wall 50.00 SF 0.45 22.45 65 Cure Concrete Wall 450.00 SF 0.31 139.34 70 Patch & Point Walls 400.00 SF 0.43 173.40 75 Reinforcement 3,989.47 LB 1.16 4,630.04 20 Outlet 30in BFV Valve 1.00 EA 38,801.70 38,801.70 63 Exc Lay Backfill 30in Bell & SP Steel Pipe 725.00 LF 193.77 140,485.86 15 Exc Lay Backfill Pipeline 30in Bell & Sp Steel Pip 725.00 LF 193.77 140,485.86 65 Riprap Outlet 250.00 CY 204.63 51,158.17 10 Place Riprap & Bedding 250.00 CY 204.63 51,158.17 Intake 1.00 LS 77,568.83 77,568.83 70 Intake 1.00 LS 77,568.83 77,568.83 10 Intake Concrete 31.00 CY 760.15 23,564.63 8/29 Activity Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Item Description Quantity UOM Unit Cost Total Cost 10 Intake Concrete 31.00 CY 760.15 23,564.63 10 Foundation Prep 140.48 SF 0.24 33.88 15 Build Base Slab Forms 28.31 SF 4.98 140.84 20 SSM Base Slab Forms 28.31 SF 17.15 485.54 25 Place Conrete Base Slab 10.44 CY 208.71 2,179.39 30 Finish Concrete Base Slab 140.48 SF 0.52 72.61 35 Cure Concrete Base Slab 168.79 SF 0.29 48.73 40 Build Wall Forms 447.71 SF 9.40 4,208.98 45 SSM Wall Forms 447.71 SF 8.21 3,674.54 50 Joint Prep on Slab 27.00 SF 0.90 24.33 55 Place Concrete Wall 16.15 CY 208.75 3,371.87 60 Finish Concrete Wall 27.00 SF 0.45 12.13 65 Cure Concrete Wall 474.71 SF 0.31 146.99 70 Patch & Point Walls 447.71 SF 0.43 194.08 75 Reinforcement 7,729.61 LB 1.16 8,970.71 20 Intake 30in Check Valve 1.00 EA 19,004.20 19,004.20 20 Trashrack 1.00 EA 35,000.00 35,000.00 Stetson Creek Diversion 1.00 LS 778,763.42 778,763.42 85 Diversion Dam Stetson Creek 1.00 LS 778,763.42 778,763.42 10 Clearing 1.00 AC 24,619.67 24,619.67 12 Stetson Creek Structure Excavation 1,008.00 CY 24.43 24,623.17 13 Rockbolts 1,500.00 LF 31.73 47,596.29 14 Rock Face Drains 800.00 LF 9.26 7,408.46 15 Concrete Stetson Creek Diversion Structure 719.00 CY 765.71 550,548.69 10 Diversion structure Concrete 719.00 CY 765.71 550,548.69 10 Foundation Prep 3,258.21 SF 0.24 785.91 15 Build Base Slab Forms 656.56 SF 4.98 3,266.52 20 SSM Base Slab Forms 656.56 SF 17.15 11,261.42 25 Pl C t B Sl b 242 19 CY 208 71 50 547 6725 Place Conrete Base Slab 242.19 CY 208.71 50,547.67 30 Finish Concrete Base Slab 3,258.21 SF 0.52 1,684.14 35 Cure Concrete Base Slab 3,914.77 SF 0.29 1,130.26 40 Build Wall Forms 10,383.87 SF 9.40 97,621.22 45 SSM Wall Forms 10,383.87 SF 8.21 85,225.65 50 Joint Prep on Slab 626.29 SF 0.90 564.28 55 Place Concrete Wall 374.64 CY 208.75 78,205.73 60 Finish Concrete Wall 626.29 SF 0.45 281.24 65 Cure Concrete Wall 11,010.16 SF 0.31 3,409.30 70 Patch & Point Walls 10,383.87 SF 0.43 4,501.51 75 Reinforcement 179,276.97 LB 1.16 208,062.51 80 Waterstop at Walls 312.20 LF 12.82 4,001.33 20 Diversion Structure Mechanical 1.00 LS 123,967.15 123,967.15 10 48in Sluice Gate 1.00 EA 50,000.00 50,000.00 15 36in Sluice Gate 1.00 EA 36,000.00 36,000.00 20 Trashrack 28 x 28 1.00 EA 25,000.00 25,000.00 21 Safety Railing 60.00 LF 81.65 4,899.00 22 Grating 264.00 SF 30.56 8,068.14 Instrumentation 1.00 LS 210,000.00 210,000.00 86 Instrumentation ( Flow Meters & Guages) 1.00 LS 210,000.00 210,000.00 Stetson Creek Pipeline 1.00 LS 5,322,204.49 5,322,204.49 92 Clearing 15.00 AC 5,329.69 79,945.30 10 Clearing 15.00 AC 5,329.69 79,945.30 95 Pipeline 11,910.00 LF 414.78 4,940,003.59 10 Pipeline Common Excavation 50,000.00 CY 8.04 401,935.66 12 Pipeline Rock Excavation 25,000.00 CY 16.84 420,940.94 10 Drill and Shoot 25,000.00 CY 4.62 115,388.19 10 Drill and Shoot Production 25,000.00 CY 4.62 115,388.19 12 Excavate Rock 25,000.00 CY 12.22 305,552.75 14 Culvert Pipe 500.00 LF 115.57 57,785.86 9/29 Activity Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Item Description Quantity UOM Unit Cost Total Cost 16 Rock Anchors 7,500.00 LF 34.95 262,157.24 10 Rock Bolts 7,500.00 LF 34.95 262,157.24 18 Rock Face Drains 4,000.00 LF 9.26 37,042.29 22 Pipeline Exc & Lay HDPE Pipe 36in 11,270.00 LF 239.69 2,701,254.02 24 Pipeline Bedding 2,200.00 CY 76.50 168,300.88 26 Pipeline Select Backfill 1.5 in Minus 9,000.00 CY 76.50 688,503.60 28 Pipeline Backfill Common 7,400.00 CY 7.22 53,393.96 30 Gabion Walls 4,000.00 SF 35.00 140,000.00 35 Trench Under Drain 500.00 LF 17.38 8,689.15 96 Outlet Pipe in Reservoir 400.00 LF 655.64 262,255.60 10 Freight In & Out Fexifloats 18.00 LDS 3,000.00 54,000.00 30 Assemble Dock & Crane Barge 1.00 LS 35,078.80 35,078.80 31 Mobilize Crane 1.00 LS 6,000.00 6,000.00 40 Pipeline HDPE Pipe 36in Fuze Pipe 400.00 LF 153.36 61,345.60 45 Set & Anchor Pipe to Lake Bottom 400.00 LF 264.58 105,831.20 97 Energy Dissapation Structure 1.00 LS 40,000.00 40,000.00 INDIRECTS 1.00 LS 4,134,413.00 4,134,413.00 98 Indirects 1.00 LS 1,298,513.00 1,298,513.00 10 Indirects 1.00 LS 923,422.00 923,422.00 20 Labor Overtime 1.00 LS 375,091.00 375,091.00 99 Contingency 1.00 LS 2,835,900.00 2,835,900.00 10/29 Estimate Line Detail Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost DIRECTS SIPHON 1.00 LS 34,117 2,206,418 1,145,079 318,964 4,150,140 1,038,532 8,859,133 34,117.29 2,206,418.08 1,145,079.38 318,963.69 4,150,139.65 1,038,532.00 8,859,132.80 Mobilization 1.00 LS 350,000 350,000 350,000.00 350,000.00 10 Mobilization 1.00 LS 350,000 350,000 350,000.00 350,000.00 10 Mobilization 1.00 LS 350,000 350,000 350,000.00 350,000.00 Mobilization 1.0 LS 350,000.00 350,000 Main Access Road 1.00 LS 2,271 150,830 67,032 254,750 20,000 492,613 2,271.03 150,830.37 67,032.21 254,750.00 20,000.00 492,612.58 15 Main Access Road 4.50 Mile 2,271 150,830 67,032 254,750 20,000 492,613 504.67 33,517.86 14,896.05 56,611.11 4,444.44 109,469.46 10 Main Access Road Clearing 3.30 AC 89 5,567 1,305 6,872 27.00 1,686.89 395.39 2,082.28 Prod=1.00 AC/hour, 27.000MH/AC, 0.04 AC/MH, 3.30 hour Clear Right of Way 1.00 EA 2082.28 Pusher 1.0 61.51 203 General Labourer 20.0 60.51 3,994 Equipment Foreman 1.0 72.00 238 Backhoe Operator 1.0 69.38 229 Dozer Operator 1.0 69.38 229 Truck Driver 2.0 66.77 441 Oiler 1.0 70.88 234 305 Hsp Bulldozer ( Cat D8 ) 1.0 136.76 451 2.6 CY Backhoe (Cat 350) 1.0 98.70 326 20 Ton (10 CY) Tandem Truck 1.0 38.17 126 10 Ton All Terrain Vehicle ( Nodwell 110 ) 1.0 81.61 269 3/4 Ton Pickup Truck 2x2 1.0 11.14 37 3/4 Ton Crew Cab Truck 1.0 11.34 37 5 Ton Flat Bed Truck 1.0 17.67 58 15 Access Road Grading 42,240.00 SY 704 48,756 25,247 74,003 0.02 1.15 0.60 1.75 Prod=300.00 SY/hour, 0.017MH/SY, 60.00 SY/MH, 140.80 hour Grading Access 1.00 EA 525.59 Foreman 1.0 71.37 10,049 Equip Oper Cl 3 (Grader) 1.0 69.38 9,769 Equip Oper Cl 4 (Roller) 1.0 69.38 9,769 Equip Oper Cl 4 (Gradechecker) 1.0 69.38 9,769 Truck Driver Cl 4 (Water) 1.0 66.77 9,401 200 Hsp Grader (Cat 14G) 1.0 87.75 12,355 15 Ton Compactor 84" (Cat 563) 1.0 47.13 6,636 3/4 Ton Pickup Truck 2x2 1.0 11.14 1,569 5000 Gallon Watertanker 1.0 33.29 4,687 20 Access Road Drainage 2,000.00 LF 1,333 86,490 34,507 74,000 194,997 0.67 43.25 17.25 37.00 97.50 Prod=12.00 LF/hour, 0.667MH/LF, 1.50 LF/MH, 166.67 hour Exc Lay Backfill Pipe 1.00 EA 725.98 F 1 0 71 37 11 895Foreman 1.0 71.37 11,895 Equip Oper Cl 3 (Backhoe) 1.0 69.38 11,563 Equip Oper Cl 3 (Loader) 1.0 69.38 11,563 Labor Cl 5 (Pipe) 4.0 60.51 40,340 Truck Driver Cl 4 (Water) 1.0 66.77 11,128 3.5 CY Loader (Cat 950) 1.0 58.84 9,807 2.6 CY Backhoe (Cat 350) 1.0 98.70 16,450 Jumping Jack Handheld Packer 1.0 4.12 687 24" Smooth Drum Manual (Bomag 60) 1.0 6.41 1,068 3/4 Ton Pickup Truck 2x2 1.0 11.14 1,857 3000 Gallon Watertruck 1.0 27.83 4,638 Access Road Pipe 2,000.0 LF 37.00 74,000 25 Access Road Gravel Surfacing 3,615.00 CY 145 10,017 5,974 180,750 196,741 0.04 2.77 1.65 50.00 54.42 Prod=150.00 CY/hour, 0.040MH/CY, 25.00 CY/MH, 24.10 hour Place Compact Grade Road Base Gravel 1.00 EA 663.54 Foreman 1.0 71.37 1,720 Equip Oper Cl 3 (Grader) 1.0 69.38 1,672 Equip Oper Cl 3 (Dozer) 1.0 69.38 1,672 Equip Oper Cl 4 (Roller) 1.0 69.38 1,672 Equip Oper Cl 4 (Gradechecker) 1.0 69.38 1,672 Truck Driver Cl 4 (Water) 1.0 66.77 1,609 170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 1,653 200 Hsp Grader (Cat 14G) 1.0 87.75 2,115 15 Ton Compactor 84" (Cat 563) 1.0 47.13 1,136 3/4 Ton Pickup Truck 2x2 1.0 11.14 268 5000 Gallon Watertanker 1.0 33.29 802 Road Base Gravel 3,615.0 CY 50.00 180,750 30 Access Road Stream Crossings 2.00 EA 20,000 20,000 10,000.00 10,000.00 Stream Crossings 2.0 EA 10,000.00 20,000 Erosion Control & Restoration 1.00 LS 1,574 103,262 54,045 69,590 80,000 306,897 1,574.15 103,261.78 54,044.91 69,590.00 80,000.00 306,896.70 30 Erosion Control 1.00 LS 1,574 103,262 54,045 69,590 226,897 1,574.15 103,261.78 54,044.91 69,590.00 226,896.70 Prod=196.85 FT/hour, 0.020MH/FT, 49.21 FT/MH, 152.40 hour Erect Silt Fence with Rubber Tire Backhoe 1.00 EA 305.85 Foreman Roadwork 1.0 71.11 10,837 Labourer Roadwork 2.0 60.51 18,443 Backhoe Operator 1.0 69.38 10,574 1.7 CY Backhoe Loader (Case680) 1.0 35.51 5,412 1/2 Ton Pickup Truck 2x2 1.0 8.83 1,346 Prod=10.00 EA/hour, 0.400MH/EA, 2.50 EA/MH, 50.00 hour Place Straw Bales 1.00 EA 305.85 Foreman Roadwork 1.0 71.11 3,556 Labourer Roadwork 2.0 60.51 6,051 Backhoe Operator 1.0 69.38 3,469 1.7 CY Backhoe Loader (Case680) 1.0 35.51 1,776 1/2 Ton Pickup Truck 2x2 1.0 8.83 442 Prod=6.54 CY/hour, 0.382MH/CY, 2.62 CY/MH, 305.82 hour Place Rock Protection 1.00 EA 311.955 Skilled Labourer Roadwork 1.0 60.51 18,505 12/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost Backhoe Operator 1.0 69.38 21,218 Loader Operator 0.5 69.38 10,609 2.0 CY Loader (CAT IT28) 0.5 38.33 5,861 2.0 CY Backhoe ( Cat 330 ) 1.0 80.43 24,597 20 Ton (10 CY) Tandem Truck-Operated 1.0 47.78 14,612 9" Riprap (250mm) 4,000.0 TN 12.65 50,600 Heavy Duty Silt Fence 30,000.0 FT 0.55 16,500 Straw Bales 500.0 EA 3.98 1,990 Stakes for Straw Bales (2" x 2" x 4 ft) 500.0 EA 1.00 500 35 Restoration 20.00 AC 80,000 80,000 4,000.00 4,000.00 Seeding & Wood Fibre Mulch 20.0 AC 4,000.00 80,000 Spillway Excavation & Backfill for Pipe 1.00 LS 5,466 355,676 134,148 67,966 478,905 1,036,696 5,466.48 355,676.11 134,148.42 67,966.00 478,905.00 1,036,695.53 40 Spillway Excavation & Embankment 10,850.00 CY 2,514 165,903 113,798 67,966 347,667 0.23 15.29 10.49 6.26 32.04 10 Drill & Shoot 10,850.00 CY 991 61,438 17,178 42,966 121,582 0.09 5.66 1.58 3.96 11.21 Prod=262.64 CY/hour, 0.053MH/CY, 18.76 CY/MH, 41.31 hour Drill Rock 1.00 EA 1183.82 Driller 4.0 60.51 9,999 General Labour Foreman 1.0 61.51 2,541 General Labourer 2.0 60.51 5,000 Helper 4.0 59.68 9,862 Truck Driver 1.0 66.77 2,758 Mechanics Helper 1.0 65.00 2,685 Oiler 1.0 70.88 2,928 Hydraulic Drill 3" (AC1238/Tam400) 4.0 73.85 12,204 3/4 Ton Pickup Truck 2x2 1.0 11.14 460 3/4 Ton Crew Cab Truck 1.0 11.34 468 Prod=262.64 FT/hour, 0.038MH/FT, 26.26 FT/MH, 41.31 hour Blast Rock 1.00 EA 719.16 Powderman 2.0 60.51 5,000 General Labour Foreman 1.0 61.51 2,541 General Labourer 5.0 60.51 12,499 Backhoe Operator 1.0 69.38 2,866 Truck Driver 1.0 66.77 2,758 1.7 CY Backhoe ( JD 790 ) 1.0 68.92 2,847 3/4 Ton Crew Cab Truck 1.0 11.34 468 5 Ton Flat Bed Truck 1.0 17.67 730 Drill Bits & Steel (65mm) 2-1/2 inch 10,850.0 FT 0.72 7,812 Amonium Nitrate Fuel Oil 10,850.0 LB 0.50 5,425 Electric Blasting Caps 10,850.0 EA 2.74 29,729 12 Spillway Rock Excavation 10,850.00 CY 723 50,140 47,828 97,968 0.07 4.62 4.41 9.03 Prod=150.00 CY/hour, 0.067MH/CY, 15.00 CY/MH, 72.33 hour Excavation Crew 1.00 EA 1354.39 Foreman 1.0 71.37 5,162 Equip Oper Cl 3 (Backhoe) 1.0 69.38 5,018 Equip Oper Cl 3 (Grader) 1.0 69.38 5,018 Equip Oper Cl 3 (Dozer) 1.0 69.38 5,018 Equip Oper Cl 7 Art truck 4.0 69.38 20,074 E i O Cl 6 G d h k 1 0 69 38 5 018Equip Oper Cl 6 Gradechecker 1.0 69.38 5,018 Truck Driver Cl 4 (Water) 1.0 66.77 4,830 170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 4,960 200 Hsp Grader (Cat 14G) 1.0 87.75 6,347 2.6 CY Backhoe (Cat 350) 1.0 98.70 7,139 30 Ton Articulated Truck (Cat D300) 4.0 90.44 26,167 3/4 Ton Pickup Truck 2x2 1.0 11.14 806 5000 Gallon Watertanker 1.0 33.29 2,408 15 Backfill 9,222.50 CY 799 54,325 48,793 103,118 0.09 5.89 5.29 11.18 Prod=150.00 CY/hour, 0.087MH/CY, 11.54 CY/MH, 61.48 hour Haul Place Backfill Crew 1.00 EA 1677.17 Foreman 1.0 71.37 4,388 Equip Oper Cl 3 (Dozer) 2.0 69.38 8,531 Equip Oper Cl 3 (Backhoe) 1.0 69.38 4,266 Equip Oper Cl 4 (Roller) 1.0 69.38 4,266 Equip Oper Cl 7 Art truck 4.0 69.38 17,063 Equip Oper Cl 6 Gradechecker 1.0 69.38 4,266 Truck Driver Cl 4 (Water) 1.0 66.77 4,105 Labourer 2.0 60.51 7,441 170 Hsp Bulldozer ( Cat D6 ) 2.0 68.57 8,432 2.6 CY Backhoe (Cat 350) 1.0 98.70 6,068 30 Ton Articulated Truck (Cat D300) 4.0 90.44 22,242 26" Smotth Drum Manual (Bomag 65) 1.0 11.32 696 30 Ton Compactor 315 hsp (Cat 825) 1.0 140.24 8,622 3/4 Ton Pickup Truck 2x2 1.0 11.14 685 5000 Gallon Watertanker 1.0 33.29 2,047 25 Tempory Shoreing 1.36 LS 25,000 25,000 18,433.18 18,433.18 Tempory Shoreing 1.0 LS 25,000.00 25,000 41 Concrete Cut Off 52.00 CY 30 1,863 254 8,736 10,853 0.57 35.83 4.89 168.00 208.71 25 Place Concrete 52.00 CY 30 1,863 254 8,736 10,853 0.57 35.83 4.89 168.00 208.71 Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 3.31 hour Place Concrete with Pump 1.00 EA 638.98 Concrete Foreman 1.0 71.11 236 Concrete Labourer 3.0 60.51 601 Vibrator Operator 2.0 61.51 408 Concrete Truck Spotter 1.0 60.51 200 Formsetter 1.0 65.61 217 Concrete Pump Operator 1.0 60.51 200 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 218 Concrete Vibrator-Normal 2.0 0.54 4 10 KW Generator Set (Gas) 2.0 4.93 33 4000 PSI (30MPA) Readymix Concrete 54.6 cy 160.00 8,736 42 Concrete Encase Pipeline 378.00 CY 217 13,542 1,847 63,504 78,893 0.57 35.83 4.89 168.00 208.71 25 Place Concrete 378.00 CY 217 13,542 1,847 63,504 78,893 0.57 35.83 4.89 168.00 208.71 Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 24.08 hour Place Concrete with Pump 1.00 EA 638.98 13/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost Concrete Foreman 1.0 71.11 1,713 Concrete Labourer 3.0 60.51 4,372 Vibrator Operator 2.0 61.51 2,963 Concrete Truck Spotter 1.0 60.51 1,457 Formsetter 1.0 65.61 1,580 Concrete Pump Operator 1.0 60.51 1,457 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 1,583 Concrete Vibrator-Normal 2.0 0.54 26 10 KW Generator Set (Gas) 2.0 4.93 237 4000 PSI (30MPA) Readymix Concrete 396.9 cy 160.00 63,504 42 Concrete Slab Spillway 1,240.00 CY 2,473 159,535 13,993 348,540 522,068 1.99 128.66 11.28 281.08 421.02 10 Foundation Preparation 16,275.00 SF 252 15,673 4,120 720 20,512 0.02 0.96 0.25 0.04 1.26 Prod=323.39 SF/hour, 0.016MH/SF, 64.68 SF/MH, 50.33 hour Foundation Preparation Manual 1.00 EA 393.28 Loader Operator 1.0 69.38 3,492 Labourer 4.0 60.51 12,181 3.5 CY Loader (Cat 950) 1.0 73.65 3,707 22" Smooth Drum Manual (Bomag 55) 1.0 8.21 413 Granular Backfill 48.0 TN 15.00 720 11 Reinforcement 186,000.00 LB 1,106 74,032 2,333 139,500 215,865 0.01 0.40 0.01 0.75 1.16 Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 31.00 hour Handle Reinforcing Steel 1.00 EA 274.64 Rodman Helper 2.0 65.00 4,030 Crane Operator Class A 1.0 69.38 2,151 20 Ton Truck Crane 1.0 58.07 1,800 4 Tonne Forklift (JCB-8000lb) 1.0 17.19 533 Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 168.78 hour Place Reinforcing Steel 1.00 EA 402 Rodman Foreman 1.0 68.20 11,511 Rodman 4.0 67.20 45,369 Rodman Helper 1.0 65.00 10,971 Supply Rebar 186,000.0 lb 0.75 139,500 12 Place Concrete 1,240.00 CY 919 57,674 7,044 208,320 273,038 0.74 46.51 5.68 168.00 220.19 Prod=13.50 CY/hour, 0.741MH/CY, 1.35 CY/MH, 91.85 hour Place Concrete with Pump 1.00 EA 704.59 Concrete Foreman 1.0 71.11 6,532 Concrete Labourer 3.0 60.51 16,674 Vibrator Operator 2.0 61.51 11,300 Concrete Truck Spotter 1.0 60.51 5,558 Formsetter 2.0 65.61 12,053 Concrete Pump Operator 1.0 60.51 5,558 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 6,039 Concrete Vibrator-Normal 2.0 0.54 99 10 KW Generator Set (Gas) 2.0 4.93 906 4000 PSI (30MPA) Readymix Concrete 1,302.0 CY 160.00 208,320 14 Finish Concrete Base Slab 16,275.00 SF 136 8,412 8,412 0.01 0.52 0.52 Prod=239.63 sf/hour, 0.008MH/sf, 119.81 sf/MH, 67.92 hour Finish Concrete with Trowel 1.00 EA 123.86 C t Fi i h 2 0 61 93 8 412Cement Finisher 2.0 61.93 8,412 16 Cure Concrete 1,240.00 CY 62 3,744 496 4,240 0.05 3.02 0.40 3.42 Prod=80.49 CY/hour, 0.050MH/CY, 20.12 CY/MH, 15.41 hour Cure Slab Concrete 1.00 EA 275.25 Labour Foreman 1.0 61.51 948 Concrete Labourer 3.0 60.51 2,797 10 KW Generator Set (Gas) 2.0 5.94 183 3" Gas Water Pump 20,000 gph 1.0 6.11 94 1/2 Ton Pickup Truck 4x4 1.0 14.22 219 43 30 in Bell & Sp Steel Pipe 775.00 LF 233 14,833 4,256 58,125 77,214 0.30 19.14 5.49 75.00 99.63 Prod=20.00 LF/hour, 0.300MH/LF, 3.33 LF/MH, 38.75 hour Lay Pipe 1.00 EA 492.63 Foreman 1.0 71.37 2,766 Equip Oper Cl 3 (Backhoe) 1.0 69.38 2,688 Labor Cl 5 (Pipe) 4.0 60.51 9,379 2.6 CY Backhoe (Cat 350) 1.0 98.70 3,825 3/4 Ton Pickup Truck 2x2 1.0 11.14 432 30 in Bell & Sp Steel Pipe 775.0 LF 75.00 58,125 Inlet/Outlet & Siphon Pipe 1.00 LS 1,415 93,398 41,753 3,564 145,676 284,391 1,415.34 93,398.45 41,752.54 3,564.00 145,676.27 284,391.26 17 Inlet Outlet Channel Excavation 3,800.00 CY 254 17,628 16,815 34,443 0.07 4.64 4.43 9.06 Prod=149.43 CY/hour, 0.067MH/CY, 14.94 CY/MH, 25.43 hour Excavation Crew 1.00 EA 1354.39 Foreman 1.0 71.37 1,815 Equip Oper Cl 3 (Backhoe) 1.0 69.38 1,764 Equip Oper Cl 3 (Grader) 1.0 69.38 1,764 Equip Oper Cl 3 (Dozer) 1.0 69.38 1,764 Equip Oper Cl 7 Art truck 4.0 69.38 7,058 Equip Oper Cl 6 Gradechecker 1.0 69.38 1,764 Truck Driver Cl 4 (Water) 1.0 66.77 1,698 170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 1,744 200 Hsp Grader (Cat 14G) 1.0 87.75 2,232 2.6 CY Backhoe (Cat 350) 1.0 98.70 2,510 30 Ton Articulated Truck (Cat D300) 4.0 90.44 9,200 3/4 Ton Pickup Truck 2x2 1.0 11.14 283 5000 Gallon Watertanker 1.0 33.29 847 60 Outlet 1.00 LS 186 12,651 1,154 3,564 40,935 58,304 186.04 12,651.36 1,154.24 3,564.00 40,934.61 58,304.21 10 Outlet Structure Concrete 16.00 CY 146 9,464 540 3,564 5,935 19,503 9.13 591.50 33.74 222.75 370.91 1,218.91 10 Outlet Concrete 16.00 CY 146 9,464 540 3,564 5,935 19,503 9.13 591.50 33.74 222.75 370.91 1,218.91 10 Foundation Prep 154.00 SF 0 31 7 37 0.00 0.20 0.04 0.24 Prod=960.00 SF/hour, 0.003MH/SF, 320.00 SF/MH, 0.16 hour Foundation Prep 1.00 EA 231.56 General Labourer 2.0 60.51 19 14/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost Backhoe Operator 1.0 69.38 11 1.7 CY Backhoe Loader (Case680) 1.0 35.51 6 22" Smooth Drum Manual (Bomag 55) 1.0 5.65 1 15 Build Base Slab Forms 50.00 SF 7 473 16 255 744 0.15 9.47 0.32 5.09 14.88 Prod=27.38 sf/hour, 0.146MH/sf, 6.84 sf/MH, 1.83 hour Fabricate Light Formwork 1.00 EA 268.075 Formsetter Foreman 1.0 66.61 122 Formsetter 2.0 65.61 240 Formsetter Helper 1.0 61.41 112 5 Ton Flat Bed Truck 0.5 17.67 16 Supply Light Wood Form 50.0 sf 5.09 255 20 SSM Base Slab Forms 50.00 SF 13 825 32 50 908 0.26 16.51 0.65 1.00 18.15 Prod=27.38 sf/hour, 0.256MH/sf, 3.91 sf/MH, 1.83 hour Set Strip Slab on Grade Edge Forms 1.00 EA 469.54 Formsetter Foreman 1.0 66.61 122 Formsetter 4.0 65.61 479 Formsetter Helper 2.0 61.41 224 5 Ton Flat Bed Truck 1.0 17.67 32 Form Supplies 50.0 SF 1.00 50 25 Place Conrete Base Slab 6.00 CY 3 215 29 1,008 1,252 0.57 35.83 4.89 168.00 208.71 Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 0.38 hour Place Slab Concrete with Pump 1.00 EA 638.98 Concrete Foreman 1.0 71.11 27 Concrete Labourer 3.0 60.51 69 Vibrator Operator 2.0 61.51 47 Concrete Truck Spotter 1.0 60.51 23 Formsetter 1.0 65.61 25 Concrete Pump Operator 1.0 60.51 23 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 25 Concrete Vibrator-Normal 2.0 0.54 0 10 KW Generator Set (Gas) 2.0 4.93 4 4000 PSI (30MPA) Readymix Concrete 6.3 cy 160.00 1,008 30 Finish Concrete Base Slab 154.00 SF 1 80 80 0.01 0.52 0.52 Prod=239.63 sf/hour, 0.008MH/sf, 119.81 sf/MH, 0.64 hour Finish Concrete with Trowel 1.00 EA 123.86 Cement Finisher 2.0 61.93 80 35 Cure Concrete Base Slab 204.00 SF 1 59 59 0.00 0.29 0.29 Cement Finisher 1.0 EA 61.93 0.95 hour 40 Build Wall Forms 200.00 SF 37 2,418 109 3,114 5,642 0.19 12.09 0.55 15.57 28.21 Prod=32.29 sf/hour, 0.186MH/sf, 5.38 sf/MH, 6.19 hour Fabricate Gang Formwork 1.00 EA 408.13 Formsetter Foreman 1.0 66.61 413 Formsetter 4.0 65.61 1,625 Formsetter Helper 1.0 61.41 380 5 Ton Flat Bed Truck 1.0 17.67 109 Supply Symons Versiform 200.0 sf 15.57 3,114 45 SSM Wall Forms 400.00 SF 47 3,040 243 400 3,683 0.12 7.60 0.61 1.00 9.21 Prod=80.73 sf/hour, 0.118MH/sf, 8.50 sf/MH, 4.95 hour Set Strip Retaining Walls 1.00 EA 662.586 Formsetter Foreman 1.0 66.61 330 Formsetter 5.0 65.61 1,625 Formsetter Helper 3.0 61.41 913 Crane Operator Class A 0.5 69.38 172 40 Ton Hydraulic Crane (Grove700) 0.4 78.34 155 5 Ton Flat Bed Truck 1.0 17.67 88 Form Supplies 400.0 SF 1.00 400 50 Joint Prep on Slab 50.00 SF 1 41 4 45 0.01 0.83 0.08 0.91 Prod=146.25 SF/hour, 0.014MH/SF, 73.13 SF/MH, 0.34 hour Joint Prep on Slab 1.00 EA 132.6 General Labourer 2.0 60.51 41 150 CFM Diesel Compressor 1.0 11.58 4 55 Place Concrete Wall 10.00 CY 6 358 49 1,680 2,088 0.57 35.83 4.93 168.00 208.75 Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 0.64 hour Place Retaining Wall Concrete with Pump 1.00 EA 639.6 Concrete Foreman 1.0 71.11 45 Concrete Labourer 3.0 60.51 116 Vibrator Operator 2.0 61.51 78 Concrete Truck Spotter 1.0 60.51 39 Formsetter 1.0 65.61 42 Concrete Pump Operator 1.0 60.51 39 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 42 2-CY Concrete Bucket (Gravity) 1.0 0.62 0 Concrete Vibrator-Normal 2.0 0.54 1 10 KW Generator Set (Gas) 2.0 4.93 6 4,000 PSI (30 MPA) Readymix Concrete 10.5 cy 160.00 1,680 60 Finish Concrete Wall 50.00 SF 0 22 22 0.01 0.45 0.45 Prod=269.49 sf/hour, 0.007MH/sf, 134.75 sf/MH, 0.19 hour Finish Concrete with Float 1.00 EA 121.02 Concrete Labourer 2.0 60.51 22 65 Cure Concrete Wall 450.00 SF 2 139 139 0.01 0.31 0.31 Cement Finisher 1.0 EA 61.93 2.25 hour 70 Patch & Point Walls 400.00 SF 3 173 173 0.01 0.43 0.43 Cement Finisher 1.0 EA 61.93 2.80 hour 75 Reinforcement 3,989.47 LB 24 1,588 50 2,992 4,630 0.01 0.40 0.01 0.75 1.16 Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 0.66 hour Handle Reinforcing Steel 1.00 EA 274.64 Rodman Helper 2.0 65.00 86 15/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost Crane Operator Class A 1.0 69.38 46 20 Ton Truck Crane 1.0 58.07 39 4 Tonne Forklift (JCB-8000lb) 1.0 17.19 11 Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 3.62 hour Place Reinforcing Steel 1.00 EA 402 Rodman Foreman 1.0 68.20 247 Rodman 4.0 67.20 973 Rodman Helper 1.0 65.00 235 Supply Rebar 3,989.5 lb 0.75 2,992 20 Outlet 30in BFV Valve 1.00 EA 40 3,187 614 35,000 38,802 40.00 3,187.30 614.40 35,000.00 38,801.70 Prod=0.80 HR/hour, 5.000MH/HR, 0.20 HR/MH, 10.00 hour Install Valve 1.00 EA 380.17 Crane Operator Class-A 1.0 77.44 774 Pipefitter Foreman 1.0 81.79 818 Pipefitter 2.0 79.75 1,595 30 Ton Crawler Crane (Linkbelt98) 1.0 61.44 614 Outlet 30 BFV Valve 1.0 LS 35,000.00 35,000 63 Exc Lay Backfill 30in Bell & SP Steel Pipe 725.00 LF 725 46,562 15,349 78,575 140,486 1.00 64.22 21.17 108.38 193.77 15 Exc Lay Backfill Pipeline 30in Bell & Sp Steel Pipe 725.00 LF 725 46,562 15,349 78,575 140,486 1.00 64.22 21.17 108.38 193.77 Prod=7.00 LF/hour, 1.000MH/LF, 1.00 LF/MH, 103.57 hour Lay Pipe 1.00 EA 597.76 Foreman 1.0 71.37 7,392 Equip Oper Cl 3 (Backhoe) 1.0 69.38 7,186 Labor Cl 5 (Pipe) 4.0 60.51 25,068 Truck Driver Cl 4 (Water) 1.0 66.77 6,915 2.6 CY Backhoe (Cat 350) 1.0 98.70 10,223 Jumping Jack Handheld Packer 1.0 4.12 427 24" Smooth Drum Manual (Bomag 60) 1.0 6.41 664 3/4 Ton Pickup Truck 2x2 1.0 11.14 1,154 3000 Gallon Watertruck 1.0 27.83 2,882 Pipe Bedding 281.6 TN 25.00 7,040 30in Bell & SP Steel Pipe 725.0 LF 75.00 54,375 Granular Backfill 1,144.0 TN 15.00 17,160 65 Riprap Outlet 250.00 CY 250 16,558 8,434 26,167 51,158 1.00 66.23 33.74 104.67 204.63 10 Place Riprap & Bedding 250.00 CY 250 16,558 8,434 26,167 51,158 1.00 66.23 33.74 104.67 204.63 Prod=5.00 CY/hour, 1.000MH/CY, 1.00 CY/MH, 50.00 hour Place RipRap 1.00 EA 499.83 Foreman 1.0 71.37 3,569 Equip Oper Cl 3 (Backhoe) 1.0 69.38 3,469 Equip Oper Cl 3 (Loader) 1.0 69.38 3,469 Labor Cl 5 (Pipe) 2.0 60.51 6,051 3.5 CY Loader (Cat 950) 1.0 58.84 2,942 2.6 CY Backhoe (Cat 350) 1.0 98.70 4,935 3/4 Ton Pickup Truck 2x2 1.0 11.14 557 Riprap 500.0 TN 45.00 22,500 Bedding 73.3 CY 50.00 3,667 I t k 1 00 LS 189 12 708 1 225 2 323 26 313 35 000 77 569Intake 1.00 LS 189 12,708 1,225 2,323 26,313 35,000 77,569 188.70 12,707.53 1,224.85 2,323.17 26,313.29 35,000.00 77,568.83 70 Intake 1.00 LS 189 12,708 1,225 2,323 26,313 35,000 77,569 188.70 12,707.53 1,224.85 2,323.17 26,313.29 35,000.00 77,568.83 10 Intake Concrete 31.00 CY 159 10,318 610 2,323 10,313 23,565 5.12 332.83 19.69 74.94 332.69 760.15 10 Intake Concrete 31.00 CY 159 10,318 610 2,323 10,313 23,565 5.12 332.83 19.69 74.94 332.69 760.15 10 Foundation Prep 140.48 SF 0 28 6 34 0.00 0.20 0.04 0.24 Prod=960.00 SF/hour, 0.003MH/SF, 320.00 SF/MH, 0.15 hour Foundation Prep 1.00 EA 231.56 General Labourer 2.0 60.51 18 Backhoe Operator 1.0 69.38 10 1.7 CY Backhoe Loader (Case680) 1.0 35.51 5 22" Smooth Drum Manual (Bomag 55) 1.0 5.65 1 15 Build Base Slab Forms 28.31 SF 1 90 3 48 141 0.05 3.17 0.11 1.70 4.98 Prod=27.38 sf/hour, 0.146MH/sf, 6.84 sf/MH, 0.35 hour Fabricate Light Formwork 1.00 EA 268.075 Formsetter Foreman 1.0 66.61 23 Formsetter 2.0 65.61 45 Formsetter Helper 1.0 61.41 21 5 Ton Flat Bed Truck 0.5 17.67 3 Supply Light Wood Form 9.5 sf 5.09 48 20 SSM Base Slab Forms 28.31 SF 7 467 18 486 0.26 16.51 0.65 17.15 Prod=27.38 sf/hour, 0.256MH/sf, 3.91 sf/MH, 1.03 hour Set Strip Slab on Grade Edge Forms 1.00 EA 469.54 Formsetter Foreman 1.0 66.61 69 Formsetter 4.0 65.61 271 Formsetter Helper 2.0 61.41 127 5 Ton Flat Bed Truck 1.0 17.67 18 25 Place Conrete Base Slab 10.44 CY 6 374 51 1,754 2,179 0.57 35.83 4.89 168.00 208.71 Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 0.67 hour Place Slab Concrete with Pump 1.00 EA 638.98 Concrete Foreman 1.0 71.11 47 Concrete Labourer 3.0 60.51 121 Vibrator Operator 2.0 61.51 82 Concrete Truck Spotter 1.0 60.51 40 Formsetter 1.0 65.61 44 Concrete Pump Operator 1.0 60.51 40 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 44 Concrete Vibrator-Normal 2.0 0.54 1 10 KW Generator Set (Gas) 2.0 4.93 7 4000 PSI (30MPA) Readymix Concrete 11.0 CY 160.00 1,754 30 Finish Concrete Base Slab 140.48 SF 1 73 73 0.01 0.52 0.52 Prod=239.63 sf/hour, 0.008MH/sf, 119.81 sf/MH, 0.59 hour Finish Concrete with Trowel 1.00 EA 123.86 Cement Finisher 2.0 61.93 73 16/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost 35 Cure Concrete Base Slab 168.79 SF 1 49 49 0.00 0.29 0.29 Cement Finisher 1.0 EA 61.93 0.79 hour 40 Build Wall Forms 447.71 SF 28 1,804 82 2,323 4,209 0.06 4.03 0.18 5.19 9.40 Prod=32.29 sf/hour, 0.186MH/sf, 5.38 sf/MH, 4.62 hour Fabricate Gang Formwork 1.00 EA 408.13 Formsetter Foreman 1.0 66.61 308 Formsetter 4.0 65.61 1,213 Formsetter Helper 1.0 61.41 284 5 Ton Flat Bed Truck 1.0 17.67 82 Supply Symons Versiform 149.2 sf 15.57 2,323 45 SSM Wall Forms 447.71 SF 53 3,403 272 3,675 0.12 7.60 0.61 8.21 Prod=80.73 sf/hour, 0.118MH/sf, 8.50 sf/MH, 5.55 hour Set Strip Retaining Walls 1.00 EA 662.586 Formsetter Foreman 1.0 66.61 369 Formsetter 5.0 65.61 1,819 Formsetter Helper 3.0 61.41 1,022 Crane Operator Class A 0.5 69.38 192 40 Ton Hydraulic Crane (Grove700) 0.4 78.34 174 5 Ton Flat Bed Truck 1.0 17.67 98 50 Joint Prep on Slab 27.00 SF 0 22 2 24 0.01 0.82 0.08 0.90 Prod=146.25 SF/hour, 0.014MH/SF, 73.13 SF/MH, 0.18 hour Joint Prep on Slab 1.00 EA 131.77 General Labourer 1.0 60.51 11 Helper 1.0 59.68 11 150 CFM Diesel Compressor 1.0 11.58 2 55 Place Concrete Wall 16.15 CY 9 579 80 2,714 3,372 0.57 35.83 4.93 168.00 208.75 Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 1.03 hour Place Retaining Wall Concrete with Pump 1.00 EA 639.6 Concrete Foreman 1.0 71.11 73 Concrete Labourer 3.0 60.51 187 Vibrator Operator 2.0 61.51 127 Concrete Truck Spotter 1.0 60.51 62 Formsetter 1.0 65.61 68 Concrete Pump Operator 1.0 60.51 62 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 68 2-CY Concrete Bucket (Gravity) 1.0 0.62 1 Concrete Vibrator-Normal 2.0 0.54 1 10 KW Generator Set (Gas) 2.0 4.93 10 4,000 PSI (30 MPA) Readymix Concrete 17.0 CY 160.00 2,714 60 Finish Concrete Wall 27.00 SF 0 12 12 0.01 0.45 0.45 Prod=269.49 sf/hour, 0.007MH/sf, 134.75 sf/MH, 0.10 hour Finish Concrete with Float 1.00 EA 121.02 Concrete Labourer 2.0 60.51 12 65 Cure Concrete Wall 474.71 SF 2 147 147 0.00 0.31 0.31 Cement Finisher 1.0 EA 61.93 2.37 hour 70 Patch & Point Walls 447.71 SF 3 194 194 0.01 0.43 0.43 Cement Finisher 1.0 EA 61.93 3.13 hour 75 Reinforcement 7,729.61 LB 46 3,077 97 5,797 8,971 0.01 0.40 0.01 0.75 1.16 Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 1.29 hour Handle Reinforcing Steel 1.00 EA 274.64 Rodman Helper 2.0 65.00 167 Crane Operator Class A 1.0 69.38 89 20 Ton Truck Crane 1.0 58.07 75 4 Tonne Forklift (JCB-8000lb) 1.0 17.19 22 Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 7.01 hour Place Reinforcing Steel 1.00 EA 402 Rodman Foreman 1.0 68.20 478 Rodman 4.0 67.20 1,885 Rodman Helper 1.0 65.00 456 Supply Rebar 7,729.6 lb 0.75 5,797 20 Intake 30in Check Valve 1.00 EA 30 2,390 614 16,000 19,004 30.00 2,389.80 614.40 16,000.00 19,004.20 Prod=0.80 HR/hour, 3.750MH/HR, 0.27 HR/MH, 10.00 hour Install Valve 1.00 EA 300.42 Crane Operator Class-A 1.0 77.44 774 Pipefitter Foreman 1.0 81.79 818 Pipefitter 1.0 79.75 798 30 Ton Crawler Crane (Linkbelt98) 1.0 61.44 614 Outlet 30in Check Valve 1.0 LS 16,000.00 16,000 20 Trashrack 1.00 EA 35,000 35,000 35,000.00 35,000.00 Trashrack 1.0 LS 35,000.00 35,000 Stetson Creek Diversion 1.00 LS 4,444 287,935 39,288 56,177 275,832 119,532 778,763 4,444.16 287,934.58 39,287.98 56,177.14 275,831.73 119,532.00 778,763.42 85 Diversion Dam Stetson Creek 1.00 LS 4,444 287,935 39,288 56,177 275,832 119,532 778,763 4,444.16 287,934.58 39,287.98 56,177.14 275,831.73 119,532.00 778,763.42 10 Clearing 1.00 AC 283 18,030 6,590 24,620 283.33 18,029.83 6,589.83 24,619.67 Prod=0.06 AC/hour, 283.333MH/AC, 0.00 AC/MH, 16.67 hour Clear Right of Way 1.00 EA 1477.18 Pusher 1.0 61.51 1,025 General Labourer 10.0 60.51 10,085 Equipment Foreman 1.0 72.00 1,200 Backhoe Operator 1.0 69.38 1,156 Dozer Operator 1.0 69.38 1,156 Truck Driver 2.0 66.77 2,226 Oiler 1.0 70.88 1,181 305 Hsp Bulldozer ( Cat D8 ) 1.0 136.76 2,279 2.6 CY Backhoe (Cat 350) 1.0 98.70 1,645 20 Ton (10 CY) Tandem Truck 1.0 38.17 636 17/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost 10 Ton All Terrain Vehicle ( Nodwell 110 ) 1.0 81.61 1,360 3/4 Ton Pickup Truck 2x2 1.0 11.14 186 3/4 Ton Crew Cab Truck 1.0 11.34 189 5 Ton Flat Bed Truck 1.0 17.67 295 12 Stetson Creek Structure Excavation 1,008.00 CY 121 8,384 7,707 8,532 24,623 0.12 8.32 7.65 8.46 24.43 Prod=75.00 CY/hour, 0.120MH/CY, 8.33 CY/MH, 13.44 hour Excavation Crew 1.00 EA 1197.26 Foreman 1.0 71.37 959 Equip Oper Cl 3 (Backhoe) 1.0 69.38 932 Equip Oper Cl 3 (Dozer) 1.0 69.38 932 Equip Oper Cl 7 Art truck 4.0 69.38 3,730 Equip Oper Cl 6 Gradechecker 1.0 69.38 932 Truck Driver Cl 4 (Water) 1.0 66.77 897 170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 922 2.6 CY Backhoe (Cat 350) 1.0 98.70 1,327 30 Ton Articulated Truck (Cat D300) 4.0 90.44 4,862 3/4 Ton Pickup Truck 2x2 1.0 11.14 150 5000 Gallon Watertanker 1.0 33.29 447 Drill & Shoot 711.0 CY 12.00 8,532 13 Rockbolts 1,500.00 LF 229 13,888 6,918 26,790 47,596 0.15 9.26 4.61 17.86 31.73 Prod=26.25 FT/hour, 0.152MH/FT, 6.56 FT/MH, 57.14 hour Drill Install & Grout Rockbolts with Hydraulic Drill 1.00 EA 364.11 Labour Foreman 1.0 61.51 3,515 Labourer 1.0 60.51 3,458 Driller 1.0 60.51 3,458 Nozzleman 1.0 60.51 3,458 Hydraulic Drill 3" (AC1238/Tam400) 1.0 102.45 5,854 3/4 Ton Pickup Truck 4x4 1.0 18.62 1,064 14 Rock Face Drains 800.00 LF 61 3,719 3,690 7,408 0.08 4.65 4.61 9.26 Prod=26.25 FT/hour, 0.076MH/FT, 13.13 FT/MH, 30.48 hour Drill Install & Grout Rockbolts with Hydraulic Drill 1.00 EA 243.09 Labour Foreman 1.0 61.51 1,875 Driller 1.0 60.51 1,844 Hydraulic Drill 3" (AC1238/Tam400) 1.0 102.45 3,122 3/4 Ton Pickup Truck 4x4 1.0 18.62 567 15 Concrete Stetson Creek Diversion Structure 719.00 CY 3,707 241,011 14,158 56,177 239,202 550,549 5.16 335.20 19.69 78.13 332.69 765.71 10 Diversion structure Concrete 719.00 CY 3,707 241,011 14,158 56,177 239,202 550,549 5.16 335.20 19.69 78.13 332.69 765.71 10 Foundation Prep 3,258.21 SF 10 646 140 786 0.00 0.20 0.04 0.24 Prod=960.00 SF/hour, 0.003MH/SF, 320.00 SF/MH, 3.39 hour Foundation Prep 1.00 EA 231.56 General Labourer 2.0 60.51 411 Backhoe Operator 1.0 69.38 235 1.7 CY Backhoe Loader (Case680) 1.0 35.51 121 22" Smooth Drum Manual (Bomag 55) 1.0 5.65 19 15 Build Base Slab Forms 656.56 SF 32 2,079 71 1,117 3,267,,, 0.05 3.17 0.11 1.70 4.98 Prod=27.38 sf/hour, 0.146MH/sf, 6.84 sf/MH, 8.02 hour Fabricate Light Formwork 1.00 EA 268.075 Formsetter Foreman 1.0 66.61 534 Formsetter 2.0 65.61 1,052 Formsetter Helper 1.0 61.41 492 5 Ton Flat Bed Truck 0.5 17.67 71 Supply Light Wood Form 219.5 sf 5.09 1,117 20 SSM Base Slab Forms 656.56 SF 168 10,838 424 11,261 0.26 16.51 0.65 17.15 Prod=27.38 sf/hour, 0.256MH/sf, 3.91 sf/MH, 23.98 hour Set Strip Slab on Grade Edge Forms 1.00 EA 469.54 Formsetter Foreman 1.0 66.61 1,598 Formsetter 4.0 65.61 6,294 Formsetter Helper 2.0 61.41 2,946 5 Ton Flat Bed Truck 1.0 17.67 424 25 Place Conrete Base Slab 242.19 CY 139 8,676 1,183 40,688 50,548 0.57 35.83 4.89 168.00 208.71 Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 15.43 hour Place Slab Concrete with Pump 1.00 EA 638.98 Concrete Foreman 1.0 71.11 1,097 Concrete Labourer 3.0 60.51 2,801 Vibrator Operator 2.0 61.51 1,898 Concrete Truck Spotter 1.0 60.51 934 Formsetter 1.0 65.61 1,012 Concrete Pump Operator 1.0 60.51 934 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 1,015 Concrete Vibrator-Normal 2.0 0.54 17 10 KW Generator Set (Gas) 2.0 4.93 152 4000 PSI (30MPA) Readymix Concrete 254.3 cy 160.00 40,688 30 Finish Concrete Base Slab 3,258.21 SF 27 1,684 1,684 0.01 0.52 0.52 Prod=239.63 sf/hour, 0.008MH/sf, 119.81 sf/MH, 13.60 hour Finish Concrete with Trowel 1.00 EA 123.86 Cement Finisher 2.0 61.93 1,684 35 Cure Concrete Base Slab 3,914.77 SF 18 1,130 1,130 0.00 0.29 0.29 Cement Finisher 1.0 EA 61.93 18.25 hour 40 Build Wall Forms 10,383.87 SF 643 41,845 1,894 53,882 97,621 0.06 4.03 0.18 5.19 9.40 Prod=32.29 sf/hour, 0.186MH/sf, 5.38 sf/MH, 107.17 hour Fabricate Gang Formwork 1.00 EA 408.13 Formsetter Foreman 1.0 66.61 7,139 Formsetter 4.0 65.61 28,125 Formsetter Helper 1.0 61.41 6,581 5 Ton Flat Bed Truck 1.0 17.67 1,894 Supply Symons Versiform 3,460.7 sf 15.57 53,882 45 SSM Wall Forms 10,383.87 SF 1,222 78,922 6,303 85,226 0.12 7.60 0.61 8.21 Prod=80.73 sf/hour, 0.118MH/sf, 8.50 sf/MH, 128.63 hour 18/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost Set Strip Retaining Walls 1.00 EA 662.586 Formsetter Foreman 1.0 66.61 8,568 Formsetter 5.0 65.61 42,196 Formsetter Helper 3.0 61.41 23,697 Crane Operator Class A 0.5 69.38 4,462 40 Ton Hydraulic Crane (Grove700) 0.4 78.34 4,031 5 Ton Flat Bed Truck 1.0 17.67 2,273 50 Joint Prep on Slab 626.29 SF 9 515 50 564 0.01 0.82 0.08 0.90 Prod=146.25 SF/hour, 0.014MH/SF, 73.13 SF/MH, 4.28 hour Joint Prep on Slab 1.00 EA 131.77 General Labourer 1.0 60.51 259 Helper 1.0 59.68 256 150 CFM Diesel Compressor 1.0 11.58 50 55 Place Concrete Wall 374.64 CY 215 13,421 1,845 62,939 78,206 0.57 35.83 4.93 168.00 208.75 Prod=15.70 cy/hour, 0.573MH/cy, 1.74 cy/MH, 23.87 hour Place Retaining Wall Concrete with Pump 1.00 EA 639.6 Concrete Foreman 1.0 71.11 1,697 Concrete Labourer 3.0 60.51 4,333 Vibrator Operator 2.0 61.51 2,936 Concrete Truck Spotter 1.0 60.51 1,444 Formsetter 1.0 65.61 1,566 Concrete Pump Operator 1.0 60.51 1,444 124 YPH Trailer Mounted Concrete Pump 1.0 65.75 1,569 2-CY Concrete Bucket (Gravity) 1.0 0.62 15 Concrete Vibrator-Normal 2.0 0.54 26 10 KW Generator Set (Gas) 2.0 4.93 235 4,000 PSI (30 MPA) Readymix Concrete 393.4 cy 160.00 62,939 60 Finish Concrete Wall 626.29 SF 5 281 281 0.01 0.45 0.45 Prod=269.49 sf/hour, 0.007MH/sf, 134.75 sf/MH, 2.32 hour Finish Concrete with Float 1.00 EA 121.02 Concrete Labourer 2.0 60.51 281 65 Cure Concrete Wall 11,010.16 SF 55 3,409 3,409 0.00 0.31 0.31 Cement Finisher 1.0 EA 61.93 55.05 hour 70 Patch & Point Walls 10,383.87 SF 73 4,502 4,502 0.01 0.43 0.43 Cement Finisher 1.0 EA 61.93 72.69 hour 75 Reinforcement 179,276.97 LB 1,066 71,356 2,249 134,458 208,063 0.01 0.40 0.01 0.75 1.16 Prod=6,000.00 LB/hour, 0.001MH/LB, 2,000.00 LB/MH, 29.88 hour Handle Reinforcing Steel 1.00 EA 274.64 Rodman Helper 2.0 65.00 3,884 Crane Operator Class A 1.0 69.38 2,073 20 Ton Truck Crane 1.0 58.07 1,735 4 Tonne Forklift (JCB-8000lb) 1.0 17.19 514 Prod=1,102.00 lb/hour, 0.005MH/lb, 183.67 lb/MH, 162.68 hour Place Reinforcing Steel 1.00 EA 402 Rodman Foreman 1.0 68.20 11,095 Rodman 4.0 67.20 43,729 Rodman Helper 1.0 65.00 10,574 Supply Rebar 179,277.0 lb 0.75 134,458 80 Waterstop at Walls 312.20 LF 26 1,707 2,295 4,001 0.08 5.47 7.35 12.82 Formsetter 2.0 EA 65.60 13.01 hour 9" Waterstop 312.2 ft 7.35 2,295 20 Diversion Structure Mechanical 1.00 LS 43 2,903 224 9,840 111,000 123,967 43.40 2,902.80 224.35 9,840.00 111,000.00 123,967.15 10 48in Sluice Gate 1.00 EA 50,000 50,000 50,000.00 50,000.00 Sluice Gate 48in 1.0 EA 50,000.00 50,000 15 36in Sluice Gate 1.00 EA 36,000 36,000 36,000.00 36,000.00 Sluice Gate 30in 1.0 EA 36,000.00 36,000 20 Trashrack 28 x 28 1.00 EA 25,000 25,000 25,000.00 25,000.00 Trashrack 1.0 EA 25,000.00 25,000 21 Safety Railing 60.00 LF 23 1,514 145 3,240 4,899 0.38 25.23 2.42 54.00 81.65 Prod=7.89 FT/hour, 0.380MH/FT, 2.63 FT/MH, 7.60 hour Instal Steel Railings 1.00 EA 218.29 Welder 1.0 66.98 509 Carpenter Foreman 1.0 66.61 506 Carpenter 1.0 65.61 499 10 KW Generator Set (Gas) 1.0 4.93 37 250 Amp Diesel Welder 1.0 4.75 36 Acetylene Cutting Torch 1.0 2.24 17 Diamond Core Drill (Hilti) 1.0 7.17 54 Galv Steel Rail 1.5in 60.0 FT 54.00 3,240 22 Grating 264.00 SF 21 1,389 79 6,600 8,068 0.08 5.26 0.30 25.00 30.56 Prod=60.87 SF/hour, 0.078MH/SF, 12.82 SF/MH, 4.34 hour Floor Grating 1.00 EA 338.5225 Ironworker Foreman 0.5 68.20 148 Ironworker 4.0 67.20 1,166 Crane Operator Class A 0.3 69.38 75 250 Amp Diesel Welder 1.0 4.75 21 Acetylene Cutting Torch 1.0 2.24 10 20 Ton Hydraulic Crane (Grove58) 0.3 45.15 49 Steel Grating 264.0 SF 25.00 6,600 Instrumentation 1.00 LS 210,000 210,000 210,000.00 210,000.00 86 Instrumentation ( Flow Meters & Guages) 1.00 LS 210,000 210,000 210,000.00 210,000.00 Flow Meters & Guages 1.0 LS 210,000.00 210,000 19/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost Stetson Creek Pipeline 1.00 LS 18,757 1,202,609 807,588 119,343 2,968,663 224,000 5,322,204 18,757.41 1,202,609.27 807,588.47 119,343.39 2,968,663.36 224,000.00 5,322,204.49 92 Clearing 15.00 AC 1,044 65,201 14,745 79,945 69.61 4,346.71 982.98 5,329.69 10 Clearing 15.00 AC 1,044 65,201 14,745 79,945 69.61 4,346.71 982.98 5,329.69 Prod=262.64 ft/hour, 0.107MH/ft, 9.38 ft/MH, 37.29 hour Clear Right of Way 1.00 EA 2143.79 Pusher 2.0 61.51 4,588 General Labourer 20.0 60.51 45,130 Equipment Foreman 1.0 72.00 2,685 Backhoe Operator 1.0 69.38 2,587 Dozer Operator 1.0 69.38 2,587 Truck Driver 2.0 66.77 4,980 Oiler 1.0 70.88 2,643 305 Hsp Bulldozer ( Cat D8 ) 1.0 136.76 5,100 2.6 CY Backhoe (Cat 350) 1.0 98.70 3,681 20 Ton (10 CY) Tandem Truck 1.0 38.17 1,423 10 Ton All Terrain Vehicle ( Nodwell 110 ) 1.0 81.61 3,043 3/4 Ton Pickup Truck 2x2 1.0 11.14 415 3/4 Ton Crew Cab Truck 1.0 11.34 423 5 Ton Flat Bed Truck 1.0 17.67 659 95 Pipeline 11,910.00 LF 16,989 1,087,269 758,228 55,843 2,898,663 140,000 4,940,004 1.43 91.29 63.66 4.69 243.38 11.75 414.78 10 Pipeline Common Excavation 50,000.00 CY 2,876 192,373 209,562 401,936 0.06 3.85 4.19 8.04 Prod=102.58 CY/hour, 0.058MH/CY, 17.39 CY/MH, 487.41 hour Main Trench Excavation, Pipe 1.00 EA 824.638 Equipment Foreman 1.0 70.38 34,304 Packer Operator 0.3 69.38 10,145 Labourer 1.0 60.51 29,493 Water Truck Driver 0.3 66.77 9,763 Backhoe Operator 1.0 69.38 33,816 Off Hwy Truck Driver 2.3 66.77 74,852 2.6 CY Backhoe (Cat 350) 1.0 142.59 69,500 30 Ton Articulated Truck (Cat D300) 2.0 124.55 121,413 8 Ton Compactor 66" (Cat 433) 0.3 46.37 6,780 3/4 Ton Crew Cab Truck 1.0 11.34 5,527 3000 Gallon Watertruck 0.3 43.37 6,342 12 Pipeline Rock Excavation 25,000.00 CY 2,640 173,894 191,203 55,843 420,941 0.11 6.96 7.65 2.23 16.84 10 Drill and Shoot 25,000.00 CY 640 39,516 20,029 55,843 115,388 0.03 1.58 0.80 2.23 4.62 10 Drill and Shoot Production 25,000.00 CY 640 39,516 20,029 55,843 115,388 0.03 1.58 0.80 2.23 4.62 Prod=187.50 FT/hour, 0.043MH/FT, 23.44 FT/MH, 80.00 hour Drill & Blast Mass Rock with 3" Hydraulic Drill 1.00 EA 744.31 Equipment Foreman 1.0 70.38 5,630 Labourer 2.0 60.51 9,682 Powderman 1.0 60.51 4,841 Driller 3.0 60.51 14,522 Shotfirer 1.0 60.51 4,841 Hydraulic Drill 3" (AC1238/Tam400)3.0 73.85 17,724Hydraulic Drill 3 (AC1238/Tam400)3.0 73.85 17,724 3/4 Ton Pickup Truck 2x2 1.0 11.14 891 5 Ton Flat Bed Truck 1.0 17.67 1,414 Hydromite 880 Wet Holes 10% 2,500.0 LB 1.88 4,700 Shoot Line 3.3 EA 52.00 171 Between Holes QRC 1 for every 4 holes 165.8 EA 4.75 788 Drill Steel 4.0 EA 1,000.00 3,979 Drill Bits 9.3 EA 400.00 3,714 Anfo 75,000.0 LB 0.46 34,500 Booster 663.2 EA 4.85 3,217 Caps 663.2 EA 7.20 4,775 12 Excavate Rock 25,000.00 CY 2,000 134,378 171,175 305,553 0.08 5.38 6.85 12.22 Prod=100.00 CY/hour, 0.080MH/CY, 12.50 CY/MH, 250.00 hour Main Trench Excavation, Pipe 1.00 EA 1222.211 Equipment Foreman 1.0 70.38 17,595 Dozer Operator 1.0 69.38 17,345 Packer Operator 0.3 69.38 5,204 Labourer 1.0 60.51 15,128 Water Truck Driver 0.7 66.77 11,685 Backhoe Operator 1.0 69.38 17,345 Off Hwy Truck Driver 3.0 66.77 50,078 170 Hsp Bulldozer ( Cat D6 ) 1.0 94.30 23,575 2.6 CY Backhoe (Cat 350) 1.0 142.59 35,648 30 Ton Articulated Truck (Cat D300) 3.0 124.55 93,413 8 Ton Compactor 66" (Cat 433) 0.7 46.37 8,115 3/4 Ton Crew Cab Truck 1.0 11.34 2,835 3000 Gallon Watertruck 0.7 43.37 7,590 14 Culvert Pipe 500.00 LF 333 21,580 11,854 24,351 57,786 0.67 43.16 23.71 48.70 115.57 Prod=11.25 LF/hour, 0.667MH/LF, 1.50 LF/MH, 44.44 hour Exc Lay Backfill Culvert Pipeavation Crew 1.00 EA 752.28 Foreman 1.0 71.37 3,172 Equip Oper Cl 3 (Backhoe) 1.0 69.38 3,084 Equip Oper Cl 6 Gradechecker 1.0 69.38 3,084 Truck Driver Cl 4 (Water) 0.5 66.77 1,484 Labourer 4.0 60.51 10,757 2.6 CY Backhoe (Cat 350) 1.0 98.70 4,387 30 Ton Compactor 315 hsp (Cat 825) 1.0 140.24 6,233 3/4 Ton Pickup Truck 2x2 1.0 11.14 495 5000 Gallon Watertanker 0.5 33.29 740 Pipe Bedding 44.5 CY 50.00 2,226 900 mm (36") x 3.5 mm Corrugated Steel Pipe (68mm x 13mm) 500.0 FT 44.25 22,125 16 Rock Anchors 7,500.00 LF 1,222 74,228 37,835 150,095 262,157 0.16 9.90 5.04 20.01 34.95 10 Rock Bolts 7,500.00 LF 1,222 74,228 37,835 150,095 262,157 0.16 9.90 5.04 20.01 34.95 Prod=24.56 FT/hour, 0.163MH/FT, 6.14 FT/MH, 305.41 hour Drill Install Rockbolts 1.00 EA 366.92 Labour Foreman 1.0 61.51 18,786 Labourer 1.0 60.51 18,481 Driller 1.0 60.51 18,481 Nozzleman 1.0 60.51 18,481 Post-tensioning Jack 1.0 4.81 1,469 20/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost Grout Pump 1.0 10.52 3,213 Grout Plant 1.0 20.96 6,401 Motorized Manlift 30 Ft 1.0 13.74 4,196 Hydraulic Drill 3" (AC1238/Tam400) 1.0 73.85 22,555 Nut Bolt Washer Plate 651.6 EA 10.00 6,516 Resin Cartrage 651.6 EA 2.00 1,303 Rockbolt 1-1/2" 7,500.0 FT 18.97 142,275 18 Rock Face Drains 4,000.00 LF 305 18,594 18,449 37,042 0.08 4.65 4.61 9.26 Prod=26.25 FT/hour, 0.076MH/FT, 13.13 FT/MH, 152.38 hour Drill Install & Grout Rockbolts with Hydraulic Drill 1.00 EA 243.09 Labour Foreman 1.0 61.51 9,373 Driller 1.0 60.51 9,221 Hydraulic Drill 3" (AC1238/Tam400) 1.0 102.45 15,611 3/4 Ton Pickup Truck 4x4 1.0 18.62 2,837 22 Pipeline Exc & Lay HDPE Pipe 36in 11,270.00 LF 5,973 375,402 221,180 2,104,673 2,701,254 0.53 33.31 19.63 186.75 239.69 Prod=15.10 FT/hour, 0.530MH/FT, 1.89 FT/MH, 746.59 hour Polyethylene 42in Pipe, Butt Fused 1.00 EA 730.63 Backhoe Operator 1.0 69.38 51,799 Labour Foreman 1.0 61.51 45,923 Labourer 5.0 60.51 225,882 Crane Operator Class A 1.0 69.38 51,799 2.6 CY Backhoe (Cat 350) 1.0 142.59 106,457 60 KW Diesel Generator Set 1.0 20.99 15,671 3/4 Ton Pickup Truck 2x2 1.0 11.14 8,317 25 Ton Pitman Boom Truck 1.0 53.09 39,637 42 in HDPE Pipe 11,270.0 LF 186.75 2,104,673 Fusion Machine Rental 3.8 MO 13,500.00 51,098 24 Pipeline Bedding 2,200.00 CY 616 38,694 8,607 121,000 168,301 0.28 17.59 3.91 55.00 76.50 Prod=25.00 CY/hour, 0.280MH/CY, 3.57 CY/MH, 88.00 hour Place Sand Bedding, per m3 1.00 EA 537.51 Truck Driver Cl 4 (Water) 1.0 66.77 5,876 General Labour Foreman 1.0 61.51 5,413 General Labourer 4.0 60.51 21,300 Loader Operator 1.0 69.38 6,105 3.5 CY Loader (Cat 950) 1.0 58.84 5,178 3/4 Ton Pickup Truck 2x2 1.0 11.14 980 3000 Gallon Watertruck 1.0 27.83 2,449 Sand Pipe Bedding 2,420.0 CY 50.00 121,000 26 Pipeline Select Backfill 1.5 in Minus 9,000.00 CY 2,520 158,292 35,212 495,000 688,504 0.28 17.59 3.91 55.00 76.50 Prod=25.00 CY/hour, 0.280MH/CY, 3.57 CY/MH, 360.00 hour Place Select Backfill 1.00 EA 537.51 Truck Driver Cl 4 (Water) 1.0 66.77 24,037 General Labour Foreman 1.0 61.51 22,144 General Labourer 4.0 60.51 87,134 Loader Operator 1.0 69.38 24,977 3.5 CY Loader (Cat 950) 1.0 58.84 21,182 3/4 Ton Pickup Truck 2x2 1.0 11.14 4,010 3000 Gallon Watertruck 1.0 27.83 10,019 Select backfill 1.5in Minus 9,900.0 CY 50.00 495,000 28 Pipeline Backfill Common 7,400.00 CY 444 30,418 22,976 53,394 0.06 4.11 3.10 7.22 Prod=50.00 CY/hour, 0.060MH/CY, 16.67 CY/MH, 148.00 hour Common Backfill 1.00 EA 360.77 Equip Oper Cl 3 1.0 69.38 10,268 Truck Driver Cl 4 (Water) 1.0 66.77 9,882 Loader Operator 1.0 69.38 10,268 170 Hsp Bulldozer ( Cat D6 ) 1.0 68.57 10,148 3.5 CY Loader (Cat 950) 1.0 58.84 8,708 3000 Gallon Watertruck 1.0 27.83 4,119 30 Gabion Walls 4,000.00 SF 140,000 140,000 35.00 35.00 Gabion Wall 4,000.0 SF 35.00 140,000 35 Trench Under Drain 500.00 LF 61 3,794 1,350 3,545 8,689 0.12 7.59 2.70 7.09 17.38 Prod=49.15 FT/hour, 0.122MH/FT, 8.19 FT/MH, 10.17 hour Excavate & Install Sub Drains underground 1.00 EA 505.67 Backhoe Operator 1.0 69.38 706 Labour Foreman 1.0 61.51 626 Labourer 4.0 60.51 2,462 2.0 CY Backhoe ( Cat 330 ) 1.0 110.31 1,122 22" Smooth Drum Manual (Bomag 55) 1.0 8.21 84 1/2 Ton Pickup Truck 4x4 1.0 14.22 145 Geotextile 3,000.0 SF 0.10 300 Granular Backfill 50.0 TN 15.00 750 6" (150mm) CSP Perforated Pipe (1.3mm thick) 500.0 FT 4.99 2,495 96 Outlet Pipe in Reservoir 400.00 LF 724 50,140 34,616 63,500 70,000 44,000 262,256 1.81 125.35 86.54 158.75 175.00 110.00 655.64 10 Freight In & Out Fexifloats 18.00 LDS 54,000 54,000 3,000.00 3,000.00 Freight Fexifloats 9.0 LDS 6,000.00 54,000 30 Assemble Dock & Crane Barge 1.00 LS 304 21,158 10,421 3,500 35,079 304.00 21,157.92 10,420.88 3,500.00 35,078.80 Prod=1.00 HR/hour, 7.000MH/HR, 0.14 HR/MH, 40.00 hour Crane Barge crew 1.00 EA 677.66 Crane Operator Class-A 1.0 70.58 2,823 Pile Driving Foreman 1.0 73.04 2,922 Pile Driver 3.0 71.04 8,525 Pile Driver Helper 1.0 61.00 2,440 Oiler 1.0 69.38 2,775 100 Ton Crawler Crane (Linkbelt218) 1.0 158.66 6,346 1- Ton Mechanic Truck 1.0 31.88 1,275 Prod=1.00 HR/hour, 3.000MH/HR, 0.33 HR/MH, 8.00 hour Excavate & Load Backhoe 1.00 EA 559.05 Equipment Foreman 1.0 70.38 563 Backhoe Operator 1.0 69.38 555 Dozer Operator 1.0 69.38 555 305 Hsp Bulldozer ( Cat D8 ) 1.0 193.10 1,545 2.6 CY Backhoe (Cat 350) 1.0 142.59 1,141 1/2 Ton Pickup Truck 4x4 1.0 14.22 114 Crane Barge Misc Materials 1.0 LS 3,500.00 3,500 21/29 Item Description Quantity UOM Rate ManHrs Labor Equip Job Mat Perm Mat Sub/Plug Total Cost 31 Mobilize Crane 1.00 LS 6,000 6,000 6,000.00 6,000.00 Mobilize Crane 1.0 LS 6,000.00 6,000 40 Pipeline HDPE Pipe 36in Fuze Pipe 400.00 LF 140 9,497 1,849 50,000 61,346 0.35 23.74 4.62 125.00 153.36 Prod=20.00 FT/hour, 0.350MH/FT, 2.86 FT/MH, 20.00 hour Polyethylene 900mm (36") Pipe, Butt Fused 1.00 EA 567.28 Pipefitter Foreman 1.0 71.14 1,423 Pipefitter 3.0 68.11 4,087 Pipefitter Helper 2.0 65.00 2,600 Crane Operator Class A 1.0 69.38 1,388 60 KW Diesel Generator Set 1.0 20.99 420 Large Dia. Polyethylene Fusion Machine 1.0 7.21 144 3/4 Ton Pickup Truck 2x2 1.0 11.14 223 25 Ton Pitman Boom Truck 1.0 53.09 1,062 36 in HDPE Pipe 400.0 LF 125.00 50,000 45 Set & Anchor Pipe to Lake Bottom 400.00 LF 280 19,485 22,346 20,000 44,000 105,831 0.70 48.71 55.87 50.00 110.00 264.58 Prod=1.00 HR/hour, 7.000MH/HR, 0.14 HR/MH, 40.00 hour Crane Barge crew 1.00 EA 1045.78 Crane Operator Class-A 1.0 70.58 2,823 Pile Driving Foreman 1.0 73.04 2,922 Pile Driver 3.0 71.04 8,525 Pile Driver Helper 1.0 61.00 2,440 Oiler 1.0 69.38 2,775 100 Ton Crawler Crane (Linkbelt218) 1.0 158.66 6,346 250 Hsp Marine Workboat 1.0 175.00 7,000 60 x 80 x 7 Crane Barge with anchors, air, lights 1.0 225.00 9,000 Concrete Weights 20.0 EA 1,000.00 20,000 Divers team 40.0 Hour 1,100.00 44,000 97 Energy Dissapation Structure 1.00 LS 40,000 40,000 40,000.00 40,000.00 Energy Dissipation Structure 1.0 LS 40,000.00 40,000 INDIRECTS 1.00 LS 1 375,091 3,759,322 4,134,413 1.00 375,091.00 3,759,322.00 4,134,413.00 98 Indirects 1.00 LS 1 375,091 923,422 1,298,513 1.00 375,091.00 923,422.00 1,298,513.00 10 Indirects 1.00 LS 923,422 923,422 923,422.00 923,422.00 20 Labor Overtime 1.00 LS 1 375,091 375,091 1.00 375,091.00 375,091.00 Labor Overtime 1.0 EA 375,091.00 1.00 hour 99 Contingency 1.00 LS 2,835,900 2,835,900 2,835,900.00 2,835,900.00 22/29 Labor Hour Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Labor Classification & Description Code Description Labor Hours Rate Total Cost Other MWH3 Foreman 741.02 71.37 52,886.59 MWH5 Equip Oper Cl 3 148.00 69.38 10,268.24 MWH5 Equip Oper Cl 3 (Backhoe) 576.12 69.38 39,971.20 MWH5 Equip Oper Cl 3 (Dozer) 258.27 69.38 17,918.82 MWH5 Equip Oper Cl 3 (Grader) 262.66 69.38 18,223.63 MWH5 Equip Oper Cl 3 (Loader) 216.67 69.38 15,032.33 MWH6 Equip Oper Cl 4 (Gradechecker) 164.90 69.38 11,440.76 MWH6 Equip Oper Cl 4 (Roller) 226.38 69.38 15,706.48 MWH8 Equip Oper Cl 7 Art truck 690.75 69.38 47,924.19 MWH9 Equip Oper Cl 6 Gradechecker 217.13 69.38 15,064.60 MWH38 Labor Cl 5 (Pipe) 1,335.95 60.51 80,838.48 MWH43 Truck Driver Cl 4 (Water) 1,226.05 66.77 81,863.20 Sub-Total 6,063.91 407,138.51 3100 Formsetters FS Formsetter 26.02 65.60 1,706.68 Sub-Total 26.02 1,706.68 30000 Labourers Heavy120 Pusher 94.55 61.51 5,815.76 Heavy200 Powderman 162.62 60.51 9,840.37 Heavy210 Driller 405.25 60.51 24,521.53 Heavy220 Shotfirer 80.00 60.51 4,840.80 Concrete100 Concrete Foreman 161.26 71.11 11,467.34 Concrete300 Concrete Labourer 489.01 60.51 29,589.72 Concrete400 Vibrator Operator 322.52 61.51 19,838.45 Concrete500 Concrete Truck Spotter 161.26 60.51 9,757.96 Road150 Foreman Roadwork 202 40 71 11 14 392 66Road150Foreman Roadwork 202.40 71.11 14,392.66 Road410 Skilled Labourer Roadwork 305.82 60.51 18,505.28 Road420 Labourer Roadwork 404.80 60.51 24,494.45 General100 General Labour Foreman 530.62 61.51 32,638.67 General300 General Labourer 3,072.23 60.51 185,900.85 General410 Helper 169.71 59.68 10,128.56 Sub-Total 6,562.07 401,732.40 31000 Formsetters Form120 Formsetter Foreman 294.14 66.61 19,592.90 Form300 Formsetter 1,548.43 65.61 101,592.80 Form400 Formsetter Helper 599.24 61.41 36,799.38 Sub-Total 2,441.82 157,985.08 32000 Rodmen Rebar100 Rodman Foreman 342.10 68.20 23,331.33 Rebar200 Rodman 1,368.41 67.20 91,956.93 Rebar300 Rodman Helper 467.77 65.00 30,404.86 Sub-Total 2,178.28 145,693.12 33500 Cement Finishers Cement200 Cement Finisher 323.77 61.93 20,051.28 Sub-Total 323.77 20,051.28 50000 Iron & Steel Workers Iron100 Ironworker Foreman 2.17 68.20 147.89 Iron200 Ironworker 17.35 67.20 1,165.76 Sub-Total 19.52 1,313.65 200000 Equipment Operators Operator010 Equipment Foreman 825.41 70.38 58,092.26 Crane110 Crane Operator Class-A 100.00 71.95 7,195.20 Backhoe100 Backhoe Operator 764.77 69.38 53,059.47 Loader100 Loader Operator 50.33 69.38 3,491.63 Dozer100 Dozer Operator 258.00 69.38 17,900.04 Packer100 Packer Operator 221.22 69.38 15,348.42 24/29 Labor Hour Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Labor Classification & Description Code Description Labor Hours Rate Total Cost Sub-Total 2,219.72 155,087.02 210000 Pipefitters Pipefitter100 Pipefitter Foreman 20.00 71.14 1,422.80 Pipefitter200 Pipefitter 60.00 68.11 4,086.60 Pipefitter300 Pipefitter Helper 40.00 65.00 2,600.00 Sub-Total 120.00 8,109.40 300000 Labourers Labour110 Labour Foreman 1,317.59 61.51 81,044.70 Labour130 Labor Overtime 1.00 375,091.00 375,091.00 Labour130 Labourer 5,535.67 60.51 334,963.52 Driller210 Driller 545.41 60.51 33,003.01 Nozzle110 Nozzleman 362.56 60.51 21,938.33 Concrete300 Concrete Labourer 46.22 60.51 2,796.59 Pile500 Pile Driving Foreman 80.00 73.04 5,843.20 Pile510 Pile Driver 240.00 71.04 17,049.60 Pile520 Pile Driver Helper 80.00 61.00 4,880.00 Sub-Total 8,208.45 876,609.94 312300 Equipment Operators Operator010 Equipment Foreman 57.26 72.00 4,122.59 Operator200 Crane Operator Class A 900.07 69.38 62,447.08 Operator310 Backhoe Operator 1,347.90 69.38 93,517.39 Operator410 Loader Operator 748.91 69.38 51,959.44 Operator420 Dozer Operator 57.26 69.38 3,972.58 Operator730 Concrete Pump Operator 161.26 60.51 9,757.96 Sub-Total 3,272.66 225,777.04 312350 Truck Drivers Truck310 Truck Driver 197 14 66 77 13 163 06Truck310TruckDriver197.14 66.77 13,163.06 Sub-Total 197.14 13,163.06 335000 Welders Welder200 Welder 7.60 66.98 509.05 Sub-Total 7.60 509.05 580000 Mechanics Mechanic510 Mechanics Helper 41.31 65.00 2,685.27 Mechanic520 Oiler 98.57 70.88 6,986.65 Sub-Total 139.88 9,671.92 600000 Carpenters Carpenter100 Carpenter Foreman 7.60 66.61 506.24 Carpenter200 Carpenter 7.60 65.61 498.64 Sub-Total 15.20 1,004.87 2000000 Mechanical Pipefitter100 Pipefitter Foreman 20.00 81.79 1,635.80 Pipefitter200 Pipefitter 30.00 79.75 2,392.50 Sub-Total 50.00 4,028.30 3000000 Truck Drivers Water307 Water Truck Driver 321.22 66.77 21,448.03 OffHwy100 Off Hwy Truck Driver 1,871.04 66.77 124,929.33 Sub-Total 2,192.26 146,377.36 4000000 Mechanics Mechanic520 Oiler 80.00 69.38 5,550.40 Sub-Total 80.00 5,550.40 Totals:34,118.29 2,581,509.08 25/29 Equipment Hour Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Equipment Classification & Description Code Description Equip Hours Average Rate Total Cost 810000 Earthmoving Equipment D6 170 Hsp Bulldozer ( Cat D6 ) 656.27 78.37 51,432.98 D8 305 Hsp Bulldozer ( Cat D8 ) 65.26 143.67 9,375.44 IT28 2.0 CY Loader (CAT IT28) 152.91 38.33 5,861.08 950 3.5 CY Loader (Cat 950) 862.99 59.70 51,523.83 14G 200 Hsp Grader (Cat 14G) 262.66 87.75 23,048.77 790 1.7 CY Backhoe ( JD 790 ) 41.31 68.92 2,847.22 330 2.0 CY Backhoe ( Cat 330 ) 315.99 81.39 25,719.43 350 2.6 CY Backhoe (Cat 350) 2,125.38 129.51 275,258.94 26/29 Material Quantity Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Material Classification & Description Code Description Quantity UOM Rate Total Adj Cost 0 Other MAT Outlet 30 BFV Valve 1.00 LS 35,000.00 35,000.00 MAT Outlet 30in Check Valve 1.00 LS 16,000.00 16,000.00 MAT Tempory Shoreing 1.00 LS 25,000.00 25,000.00 DS Anfo 75,000.00 LB 0.46 34,500.00 DS Between Holes QRC 1 for every 4 holes 165.81 EA 4.75 787.60 DS Booster 663.25 EA 4.85 3,216.75 DS Caps 663.25 EA 7.20 4,775.38 DS Drill Bits 9.29 EA 400.00 3,714.00 DS Drill Steel 3.98 EA 1,000.00 3,978.69 DS Hydromite 880 Wet Holes 10% 2,500.00 LB 1.88 4,700.00 DS Shoot Line 3.29 EA 52.00 170.97 MAT 30 in Bell & Sp Steel Pipe 775.00 LF 75.00 58,125.00 MAT 30in Bell & SP Steel Pipe 725.00 LF 75.00 54,375.00 MAT 36 in HDPE Pipe 400.00 LF 125.00 50,000.00 MAT 42 in HDPE Pipe 11,270.00 LF 186.75 2,104,672.50 MAT Access Road Pipe 2,000.00 LF 37.00 74,000.00 MAT Bedding 73.33 CY 50.00 3,666.67 MAT Concrete Weights 20.00 EA 1,000.00 20,000.00 MAT Form Supplies 450.00 SF 1.00 450.00 MAT Freight Fexifloats 9.00 LDS 6,000.00 54,000.00 MAT Mobilize Crane 1.00 LS 6,000.00 6,000.00 MAT Pipe Bedding 44.52 CY 50.00 2,226.19 MAT Pipe Bedding 281.60 TN 25.00 7,040.00 MAT Riprap 500.00 TN 45.00 22,500.00 MAT Road Base Gravel 3,615.00 CY 50.00 180,750.00 MAT Sand Pipe Bedding 2,420.00 CY 50.00 121,000.00 MAT Select backfill 1.5in Minus 9,900.00 CY 50.00 495,000.00 ROCK BOLT Nut Bolt Washer Plate 651.64 EA 10.00 6,516.39ROCKBOLTNutBolt Washer Plate 651.64 EA 10.00 6,516.39 ROCK BOLT Resin Cartrage 651.64 EA 2.00 1,303.28 Sub-Total 112,799.59 3,393,468.42 100000 Indirect Items MAT Crane Barge Misc Materials 1.00 LS 3,500.00 3,500.00 Sub-Total 1.00 3,500.00 310000 Formwork FormSupply11010 Supply Light Wood Form 278.95 sf 5.09 1,419.84 FormSupply13020 Supply Symons Versiform 3,809.87 sf 15.57 59,319.65 Sub-Total 4,088.82 60,739.49 320000 Reinforcement Rebar11130 A Supply Rebar 376,996.05 lb 0.75 282,747.04 Sub-Total 376,996.05 282,747.04 331000 Ready Mix Concrete Readymix2113 4000 PSI (30MPA) Readymix Concrete 2,025.06 cy 160.00 324,010.11 Readymix2114 4,000 PSI (30 MPA) Readymix Concrete 420.83 cy 160.00 67,332.63 Sub-Total 2,445.89 391,342.74 336000 Concrete Accessories Waterstop61026 9" Waterstop 312.20 ft 7.35 2,294.65 Sub-Total 312.20 2,294.65 550000 Metal Fabrications MATL Galv Steel Rail 1.5in 60.00 FT 54.00 3,240.00 MATL Steel Grating 264.00 SF 25.00 6,600.00 Sub-Total 324.00 9,840.00 3125000 Erosion Control FilterFabric140 Geotextile 3,000.00 SF 0.10 300.00 Riprap110 9" Riprap (250mm) 4,000.00 TN 12.65 50,600.00 SiltFence130 Heavy Duty Silt Fence 30,000.00 FT 0.55 16,500.00 Sediment110 Straw Bales 500.00 EA 3.98 1,990.00 Sediment120 Stakes for Straw Bales (2" x 2" x 4 ft) 500.00 EA 1.00 500.00 Sub-Total 38,000.00 69,890.00 3128000 Structural Backfill Backfill130 Granular Backfill 1,242.00 TN 15.00 18,630.00 27/29 Material Quantity Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Material Classification & Description Code Description Quantity UOM Rate Total Adj Cost Sub-Total 1,242.00 18,630.00 3133000 Rock Stabilization Rockbolt220 Rockbolts 1" ( 25 mm) 517/690 Mpa Threadbar SCP Te 1,500.00 FT 17.86 26,790.00 ROCK BOLT Rockbolt 1-1/2" 7,500.00 FT 18.97 142,275.00 Sub-Total 9,000.00 169,065.00 3139000 Rock Excavation DrillSteel130 Drill Bits & Steel (65mm) 2-1/2 inch 10,850.00 FT 0.72 7,812.00 Explosive1320 Amonium Nitrate Fuel Oil 10,850.00 LB 0.50 5,425.00 Detonator1410 Electric Blasting Caps 10,850.00 EA 2.74 29,729.00 Sub-Total 32,550.00 42,966.00 3342000 Culverts CSP900x3.5 900 mm (36") x 3.5 mm Corrugated Steel Pipe (68mm x 500.00 FT 44.25 22,125.00 Sub-Total 500.00 22,125.00 3346000 Subdrains CSPS150 6" (150mm) CSP Perforated Pipe (1.3mm thick) 500.00 FT 4.99 2,495.00 Sub-Total 500.00 2,495.00 Totals: 4,469,103.34 28/29 Subcontract Quantity Summary Estimate: 03-2011 - STETSON CREEK DIVERSION UPDATE Currency: USD-United States-Dollar Subcontract Classification & Description Code Description Quantity UOM Rate Total Cost 14000 Site Services INST Flow Meters & Guages 1.00 LS 210,000.00 210,000.00 Mob Mobilization 1.00 LS 350,000.00 350,000.00 Sub-Total 560,000.00 51200 Structural Steel Cross Stream Crossings 2.00 EA 10,000.00 20,000.00 Steel320 Sluice Gate 30in 1.00 EA 36,000.00 36,000.00 Steel320 Sluice Gate 48in 1.00 EA 50,000.00 50,000.00 Steel320 Trashrack 1.00 EA 25,000.00 25,000.00 Steel320 Trashrack 1.00 LS 35,000.00 35,000.00 Sub-Total 166,000.00 54500 Supply Detail & Fab Steel Bldgs Bldg140 Energy Dissipation Structure 1.00 LS 40,000.00 40,000.00 Sub-Total 40,000.00 312000 Removals Sub Divers team 40.00 Hour 1,100.00 44,000.00 Sub-Total 44,000.00 323200 Earth Walls BinWall10 Gabion Wall 4,000.00 SF 35.00 140,000.00 Sub-Total 140,000.00 329000 Landscaping Seed110 Seeding & Wood Fibre Mulch 20.00 AC 4,000.00 80,000.00 Sub-Total 80,000.00 335000 Pipeline Drill & Shoot Drill & Shoot 711.00 CY 12.00 8,532.00 Sub-Total 8,532.00 Total: 1,038,532.00 29/29 APPENDIX C Avalanche Report APPENDIX D Dive Logs APPENDIX E Comparison of 2004 EPC and 2010 OPCC APPENDIX F Report of Geotechnical Engineering Services – Revised Draft Report STETSON CREEK DIVERSION AND COOPER LAKE DAM FACILITIES REPORT OF GEOTECHNICAL ENGINEERING SERVICES REVISED DRAFT REPORT MARCH 2011 PREPARED BY: Stetson Creek Diversion and Cooper Lake Dam Facilities Page i Report of Geotechnical Engineering Services – Revised Draft March 2011 TABLE OF CONTENTS ACRONYMS AND ABBREVIATIONS .................................................................................... iv DISCLAIMER................................................................................................................................v COPYRIGHT .................................................................................................................................v EXECUTIVE SUMMARY .................................................................................................... ES-1 1.0 INTRODUCTION............................................................................................................. 1-1 1.1 GENERAL ................................................................................................................. 1-1 1.2 HISTORY .................................................................................................................. 1-1 1.3 PROJECT DESCRIPTION ........................................................................................ 1-2 1.3.1 Background .................................................................................................... 1-2 1.3.2 Preliminary Design Project Improvements .................................................... 1-2 1.3.2.1 Diversion Dam ................................................................................ 1-2 1.3.2.2 Diversion Pipeline and Construction Access Road ........................ 1-3 1.3.2.3 Outlet Works ................................................................................... 1-3 1.4 PURPOSE AND SCOPE OF WORK........................................................................ 1-4 1.5 REPORT STRUCTURE ............................................................................................ 1-6 2.0 SITE CHARACTERIZATION ....................................................................................... 2-1 2.1 LITERATURE REVIEW .......................................................................................... 2-1 2.2 FIELD INVESTIGATIONS ...................................................................................... 2-2 2.2.1 Field Investigation Plan ................................................................................. 2-2 2.2.2 Geological Reconnaissance ........................................................................... 2-3 2.2.3 Geophysical Survey ....................................................................................... 2-3 2.2.4 Test Pit Explorations ...................................................................................... 2-3 2.2.5 Exploratory Drilling ....................................................................................... 2-3 2.2.6 Laboratory Testing ......................................................................................... 2-4 3.0 SITE CONDITIONS ......................................................................................................... 3-1 3.1 GEOLOGY ................................................................................................................ 3-1 3.1.1 Regional Geology .......................................................................................... 3-1 3.1.2 Seismicity Overview ...................................................................................... 3-2 3.1.3 Local Geology ................................................................................................ 3-4 3.2 SITE CONDITIONS .................................................................................................. 3-4 3.2.1 Surface Conditions ......................................................................................... 3-4 3.2.1.1 Diversion Dam ................................................................................ 3-4 3.2.1.2 Diversion Pipeline and Construction Access Road ........................ 3-4 3.2.1.3 Outlet Works ................................................................................... 3-5 3.2.2 Subsurface Conditions ................................................................................... 3-6 3.2.2.1 Diversion Dam ................................................................................ 3-6 3.2.2.2 Diversion Pipeline and Construction Access Road ........................ 3-7 3.2.2.3 Outlet Works ................................................................................... 3-8 3.2.2.4 Potential Borrow Sources ............................................................... 3-8 4.0 GEOTECHNICAL EVALUATIONS ............................................................................. 4-1 4.1 OVERVIEW .............................................................................................................. 4-1 4.1.1 Key Geotechnical Concerns ........................................................................... 4-1 Stetson Creek Diversion and Cooper Lake Dam Facilities Page ii Report of Geotechnical Engineering Services – Revised Draft March 2011 4.2 GEOLOGIC HAZARD ANALYSIS AND RECOMMENDATIONS ..................... 4-2 4.2.1 Seismic Hazards ............................................................................................. 4-2 4.2.1.1 Surface Rupture .............................................................................. 4-2 4.2.1.2 Liquefaction Potential ..................................................................... 4-2 4.2.1.3 Seismically Induced Settlement ...................................................... 4-2 4.2.1.4 Lateral Spreading ............................................................................ 4-3 4.2.1.5 Seiches ............................................................................................ 4-3 4.2.2 Geologic Hazards ........................................................................................... 4-3 4.3 GEOTECHNICAL ENGINEERING EVALUATIONS ........................................... 4-4 4.3.1 General ........................................................................................................... 4-4 4.3.2 Seismic Design Considerations ...................................................................... 4-4 4.3.3 Diversion Dam Foundation Design ............................................................... 4-4 4.3.3.1 Dam Foundation Excavation and Preparation ................................ 4-4 4.3.3.2 Dam Foundation Design Parameters .............................................. 4-5 4.3.4 Foundation Design Parameters for Other Facilities ....................................... 4-5 4.3.4.1 Diversion Pipeline Outlet and Siphon Intake Foundations ............. 4-6 4.3.4.2 Siphon Outlet and Butterfly Valve Structure Foundation ............... 4-7 4.3.4.3 General Foundation Recommendations .......................................... 4-7 4.3.4.4 Lateral Loads on Buried Foundation Walls .................................... 4-8 4.3.5 Diversion Pipeline and Construction Access Road ....................................... 4-9 4.3.6 Permanent Slopes ........................................................................................... 4-9 4.3.7 Excavation Evaluations ................................................................................ 4-10 4.3.7.1 General .......................................................................................... 4-10 4.3.7.2 Diversion Dam .............................................................................. 4-10 4.3.7.3 Diversion Pipeline and Construction Access Road ...................... 4-10 4.3.7.4 Outlet Works ................................................................................. 4-11 4.3.8 Borrow Sources ............................................................................................ 4-11 4.3.8.1 Borrow Material Properties and Volume ...................................... 4-11 4.3.8.2 Petrographic Evaluation of Aggregates ........................................ 4-12 4.3.8.3 Aggregate Abrasion and Soundness Testing ................................ 4-12 4.3.8.4 Soil Corrosion Potential ................................................................ 4-13 4.4 CONSTRUCTION CONSIDERATIONS ............................................................... 4-13 4.4.1 Site Preparation ............................................................................................ 4-13 4.4.2 Temporary Slopes and Excavation Support ................................................. 4-14 4.4.3 Dewatering ................................................................................................... 4-16 4.4.4 Drainage ....................................................................................................... 4-16 4.4.4.1 General .......................................................................................... 4-16 4.4.4.2 Trench Drains................................................................................ 4-16 4.4.4.3 Horizontal Drains .......................................................................... 4-17 4.4.5 Backfill Materials ......................................................................................... 4-17 4.4.5.1 Structural Fill ................................................................................ 4-17 4.4.5.2 Pipe Bedding ................................................................................. 4-18 4.4.5.3 Trench Backfill ............................................................................. 4-18 4.4.6 Protection and Preparation of Subgrades ..................................................... 4-19 5.0 RECOMMENDATIONS FOR CONSTRUCTION OBSERVATION ........................ 5-1 6.0 REFERENCES .................................................................................................................. 6-1 Stetson Creek Diversion and Cooper Lake Dam Facilities Page iii Report of Geotechnical Engineering Services – Revised Draft March 2011 TABLES Table 1 List of Recorded Earthquake Magnitudes .................................................................. 3-3 Table 2 Summary of 2009 IBC Seismic Design Paramters .................................................... 4-4 Table 3 Corrosion Testing Results ........................................................................................ 4-13 Table 4 OSHA Classification and Soil Parameters for Temporary Excavations .................. 4-15 Table 5 Summary of Rock Core Test Results ....................................................................... 4-15 FIGURES Sheet 1 Location Plan Sheet 2 Site Plan Sheet 3 Cooper Lake Dam Outlet Works - Plan Sheet 4 Cooper Lake Dam Outlet Works - Profile Sheet 5 Cooper Lake Dam Outlet Works - Sections Sheet 6 Diversion Dam and Intake Plan & Elevation Sheet 7 Diversion Pipeline STA 0+00 – STA 10+00 Plan & Profile Sheet 8 Diversion Pipeline STA 10+00 – STA 25+00 Plan & Profile Sheet 9 Diversion Pipeline STA 25+00 – STA 40+00 Plan & Profile Sheet 10 Diversion Pipeline STA 40+00 – STA 55+00 Plan & Profile Sheet 11 Diversion Pipeline STA 55+00 – STA 70+00 Plan & Profile Sheet 12 Diversion Pipeline STA 70+00 – STA 85+00 Plan & Profile Sheet 13 Diversion Pipeline STA 85+00 – STA 100+00 Plan & Profile Sheet 14 Diversion Pipeline STA 100+00 – STA 110+00 Plan & Profile Sheet 15 Diversion Pipeline STA 110+00 – STA 116+71 Plan & Profile Sheet 16 Diversion Pipeline Sections Sheet 17 Diversion Dam and Intake Geotechnical Schematics APPENDICES Appendix I 2010 Boring Procedures, Logs, and Photographs Appendix II 2010 Laboratory Testing Program and Results Appendix III 2010 Geophysical Seismic Refraction Survey & Video Core Logging Program Appendix IV 2009 Test Pit Procedures, Logs, and Photographs Appendix V 2009 Laboratory Testing Program and Results Appendix VI 2009 Geophysical Seismic Refraction Survey Program Appendix VII Selected Historical Exploration Logs Stetson Creek Diversion and Cooper Lake Dam Facilities Page iv Report of Geotechnical Engineering Services – Revised Draft March 2011 ACRONYMS AND ABBREVIATIONS AKDOT&PF Alaska Department of Transportation and Public Facilities AKOSH Alaska Occupational Safety and Health bgs Below the ground surface CAPA Central Alaska Power Association Chugach Chugach Electric Association, Inc. CMU Concrete masonry unit FERC Federal Energy Regulatory Commission fps Feet per second ft Foot (or feet) GFS Geotechnical Feasibility Study H horizontal HDPE High-Density Polyethylene M magnitude MSE Mechanically Stabilized Earth MWH MWH Americas, Inc. my Million years before present NEIC National Earthquake Information Center NGA Northwest Geophysical Associates OSHA Occupational Safety and Health Administration Project Stetson Creek Diversion and Cooper Lake Dam Facilities Project psf Pounds per square foot psi Pounds per square inch PVC Polyvinyl Chloride STA Station TAI TestAmerica, Inc. USACE U.S. Army Corps of Engineers USGS U.S. Geologic Survey V vertical Stetson Creek Diversion and Cooper Lake Dam Facilities Page v Report of Geotechnical Engineering Services – Revised Draft March 2011 DISCLAIMER This report has been prepared in accordance with the terms set out in the contract between Chugach Electric Association, Inc. (Chugach) and MWH. The findings of this report are based on new explorations, information provided by Chugach, and readily available data and information obtained from public and private sources. Additional studies (at greater cost) may or may not disclose information which may significantly modify the findings of this report. In the event that there are any changes in the nature, design, or location of the Project, or if additional subsurface data are obtained or any future additions are planned, the conclusions and recommendations contained in this report will need to be reevaluated by MWH in light of the proposed changes or additional information obtained. Neither MWH nor Chugach or any person acting on any of their behalf, make any warranty, express or implied, or assume any liability with respect to the use of any information, method, product, process, or statement contained in this report. MWH was neither requested to perform nor has performed environmental or regulatory investigations or assessments in connection with this investigation of the facilities described in this report. Also, MWH was neither requested to, nor has performed, any economic analyses or detailed evaluation of any permits or licenses in association with this report. The content of this report is governed by confidentiality clauses in the contract between MWH and Chugach. The contents of this document may not be disclosed to other parties in a manner not consistent with the terms of the confidentiality clauses of the contract. COPYRIGHT © 2011 Chugach Electric Association, Inc., Anchorage, Alaska. All rights reserved under U.S. and foreign law, treaties and conventions. The attached work was specifically ordered under an agreement with Chugach Electric Association, Inc., Anchorage, Alaska. All rights in the various work produced for or under this agreement, including but not limited to study plans and study results, drafts, charts, graphs and other forms of presentation, summaries and final work products, are the exclusive property of Chugach Electric Association. Stetson Creek Diversion and Cooper Lake Dam Facilities Page ES-1 Report of Geotechnical Engineering Services – Revised Draft March 2011 EXECUTIVE SUMMARY This report summarizes the investigation, methods, parameters, and results of evaluations conducted for the Stetson Creek Diversion and Cooper Lake Outlet Geotechnical Exploration Program. This report has been prepared in accordance with the task and scope of work authorized by Chugach Electric Association, Inc. (Chugach). Chugach intends to construct a diversion structure, diversion pipeline and access road, and reservoir outlet facility in accordance with an order from the Federal Energy Regulatory Commission outlined in their document to Chugach titled “Order on Offer of Settlement and Issuing of New License” dated August 24, 2007. The site improvements include a small diversion dam constructed on Stetson Creek, an approximate 2-mile long diversion pipeline to convey water from the diversion dam to Cooper Lake, a construction road to obtain access to the diversion dam and pipeline, and an outlet facility to allow for the passage of water from Cooper Lake downstream of Cooper Lake Dam to Cooper Creek. The results of this exploration program have determined that the Project, as conceived, is generally feasible from a geotechnical standpoint; however; it is noted that site conditions identified as part of this study may impact the initially estimated cost of construction and/or pose hazards to conceptual Project improvements. These site conditions include: Steep slopes near the diversion dam and along the diversion pipeline alignment Indications of shallow seated slope instability along the diversion pipeline alignment Difficult site access A preliminary study was conducted in 2009 to determine the geotechnical feasibility of the site improvements described above and documented in a separate Geotechnical Feasibility Study. To the extent feasible, explorations and analysis conducted as part of the 2009 site investigation and Geotechnical Feasibility Study have been incorporated into this current geotechnical evaluation. The exploration program was continued in 2010 and implemented earlier recommendations for additional geotechnical work to further investigate Project design feasibility and cost estimate assumptions. The 2010 exploration program included geological reconnaissance, geophysical seismic refraction surveys, drilling explorations and laboratory analyses. The 2010 investigations were used to characterize site conditions, evaluate potential rock excavation methods, and evaluate foundation conditions for key Project structures. The evaluations and investigations were used to help assess the Project feasibility and develop geotechnical engineering recommendations for the design of the envisioned Project. Findings of the two-season geotechnical exploration program and discussion of critical issues that may have an impact on the site improvements are described herein. In addition, geotechnical engineering recommendations for the design of the proposed Project facilities are presented. . Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-1 Report of Geotechnical Engineering Services – Revised Draft March 2011 1.0 INTRODUCTION 1.1 GENERAL This report presents MWH’s geotechnical findings and design recommendations for the Stetson Creek Diversion and Cooper Lake Dam Facilities Project (Project). The Project is located in Kenai Borough, Alaska, approximately 4 miles south of the community of Cooper Landing. The Project is located within Sections 16, 17 and 18 of Township 4 North, Range 3 West of the Seward Meridian. The Project location with respect to the surrounding physical features is shown on Figure 1. The major Project components consist of a diversion dam, a diversion pipeline, a construction access road between the existing Cooper Lake Dam and the diversion dam, and outlet works. These major components and their locations are depicted on Figures 2 and 3. Included in this report are MWH’s geotechnical evaluations and recommendations for the Project. Conclusions, interpretations, and recommendations presented in this report are based on the observations made during geological site reconnaissance, geophysical site investigations, test pit explorations, exploratory drilling, general site observations, laboratory soil and rock testing, geotechnical analyses, and engineering judgment. Two previous reports are referenced frequently in this document: Stetson Creek Diversion and Cooper Lake Dam Facilities Geotechnical Feasibility Report, January 2010 (MWH, 2010a); hereafter referred to as the 2010 GFS. Stetson Creek Diversion and Cooper Lake Dam Facilities Feasibility Report, February 2010 (MWH, 2010b); hereafter referred to as the 2010 Feasibility Study. The 2010 GFS presents a summary of the geotechnical investigations conducted during the 2009 field season. The data from the 2010 GFS are fully incorporated into this report. 1.2 HISTORY The concept of the Cooper Lake Hydroelectric Project was first suggested by the U.S. Geologic Survey (USGS) in 1915 (Ellsworth and Davenport, 1915). In 1955, the USGS published a second study of developing a hydroelectric facility near Kenai Lake, which included a study of Cooper Lake and three other nearby sites (Plafker, 1955). Ultimately, Cooper Lake was selected as the most feasible site of the four studied in 1955, and the design of the Cooper Lake Hydroelectric Project was commissioned by the Central Alaska Power Association (CAPA) on June 7, 1955 (NPC, 1955). The former Federal Power Commission, which is now the Federal Energy Regulatory Commission (FERC), granted CAPA a license for the Project on May 27, 1957, and construction began in September of 1958 (FERC, 2007). The completed Project was operational and brought online in April of 1961 (MWH, 2004). Since the Cooper Lake Project was completed, the dam has undergone at least one modification. A 6-inch thick concrete mat was added to the upstream face of the dam in 1980 (IECo, 1983). Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-2 Report of Geotechnical Engineering Services – Revised Draft March 2011 Recommendations for regrading the upstream slope and reconstructing the crest of the dam were made in 1965 (Jones, 1965). It is presumed that these recommendations were carried out during the 1980 modifications, but they may have occurred at an earlier time. Further, it is not clear to what extent these recommendations were carried out due to a lack of documentation from 1965 and 1983. The most recent proposed dam modifications were developed in 1997 (Stone & Webster, 1997). These proposed modifications were never implemented, but would have raised the crest of the dam to account for a revised, probable maximum flood while maintaining the reservoir at the licensed maximum pool elevation, which had been restricted to an elevation of 1,194 feet in previous years. 1.3 PROJECT DESCRIPTION 1.3.1 Background As part of the conditions stipulated in the first FERC relicense of the Cooper Lake Project, Chugach Electric Association (Chugach) is required to make improvements to the site in an attempt to improve downstream fish habitat. Prior to the construction of the Cooper Lake Dam, Cooper Lake was a significant source of water flow to Cooper Creek. Since the dam’s construction, flow from Cooper Lake to Cooper Creek has effectively stopped, making the glacial-fed Stetson Creek the primary source of water flowing in Cooper Creek. This shift in flow sources is believed to have caused a decrease in the downstream temperature of Cooper Creek, which in turn has reduced the quality of fish habitat. The preliminary design Project improvements are intended to increase the water temperature of Cooper Creek by diverting water from Stetson Creek to Cooper Lake and releasing warmer water from Cooper Lake downstream of Cooper Lake Dam to Cooper Creek. 1.3.2 Preliminary Design Project Improvements Preliminary design Project improvements include a diversion dam on Stetson Creek, a diversion pipeline to convey the diverted water from Stetson Creek to Cooper Lake, an access road to construct the diversion dam and pipeline, and an outlet facility to release water from Cooper Lake to Cooper Creek in a controlled manner. Descriptions of these preliminary design Project improvements are presented in the following paragraphs. 1.3.2.1 Diversion Dam The Project includes a low diversion dam that impounds water from Stetson Creek. The dam is located approximately 1.2 miles upstream of the confluence of Stetson Creek and Cooper Creek (Figure 2). The dam consists of a small concrete gravity structure with a weir spillway. The dam is fitted with a series of sluice gates to manage the flow of water being diverted to Cooper Lake. The diversion structure has a crest length of approximately 80 feet (ft), a spillway height of 13 ft and a cross-sectional base width of about 16 ft. Based on a previous preliminary Project evaluation, MWH understands that the minimum elevation of the dam needs to be around 1,294 ft in order to provide adequate flow from Stetson Creek to Cooper Lake (MWH, 2003). At the currently envisioned location, the base of the Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-3 Report of Geotechnical Engineering Services – Revised Draft March 2011 structure is approximately 1,424 ft. The crest elevation of the dam at this location is approximately 1,437 ft. A diversion dam at this site creates a minimum head differential of 227 ft between the base of diversion dam and the maximum licensed pool elevation of Cooper Lake. Anticipated foundation loads have not yet been developed for the diversion dam; however, it is anticipated that bearing pressures will be limited to approximately 4,500 pounds per square foot (psf). 1.3.2.2 Diversion Pipeline and Construction Access Road The diversion pipeline and construction access road extends from the sluice gates of the diversion dam to an outfall located approximately 1,500 ft south of Cooper Lake Dam. The pipeline generally follows slope contours sloping downward from the diversion dam to Cooper Lake at an average grade of approximately 1.8 percent (Figures 7 through 15). The pipeline follows the alignment of the associated construction access road, when feasible, and is 2.2 miles long in its current configuration. The pipeline and construction access road alignment varies from the alignment that was anticipated during the explorations conducted as part of the 2009 GFS. This revised alignment is a result of modifications to the diversion dam location and adjustments to minimize exposure to undesirable features along the alignment, including steep slopes and irregular topography, which may indicate signs of slope instability. The pipeline has a 36-inch inside diameter pipe and consists of steel, high-density polyethylene (HDPE) plastic, or a combination of the two. The pipeline is buried within road fill at a minimum depth of three feet. However, steeply dipping slopes between approximate pipeline Stations 0+00 and 37+00 may result in a minimal bench to support the diversion pipeline and construction access road along the Stetson Creek portion of the alignment. The diversion pipeline outlet is located approximately 1,500 ft south of the existing Cooper Lake Dam. The outlet facility consists of a concrete structure that will likely be supported by a slab- on-grade foundation. Structure loads were not available at the time of this report; however, it is anticipated that bearing pressures for the slab-on-grade foundation will be less than 500 psf. The construction access road will maintain a minimum cover of three feet over the diversion pipeline. The width of the road should be limited to that required by the Contractor to conduct the work safely while minimizing the impact to the surrounding areas. The Contractor will be in charge of constructing and maintaining the road such that it is adequate to support construction activities. Following construction the Contractor will grade and compact the road such that it is suitable for occasional passenger vehicle traffic at the time construction is complete and is graded to sheet water away from the road and Project improvements. MWH understands that the construction access road is not intended as a permanent feature of the Project, but may be used to access the diversion pipeline or diversion dam if feasible following construction. 1.3.2.3 Outlet Works The proposed site improvements include the construction of an outlet facility to convey water from Cooper Lake upstream of Cooper Lake Dam to Cooper Creek (Figure 3). The outlet works consists of a 30-inch diameter siphon within the existing spillway. Due to elevation constraints Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-4 Report of Geotechnical Engineering Services – Revised Draft March 2011 of siphon systems, this approach requires that a trench be excavated into the rock of the existing spillway. Siphon systems require a system to prime the outlet pipe. Priming the siphon will be accomplished by either using flow from the nearby diversion pipeline or a pump system. Flow through the conduit will be controlled from a butterfly valve constructed downstream of the existing spillway. Structures associated with the outlet works will include the siphon intake structure, butterfly valve, and outlet structure. It is anticipated that each of these facilities will be supported by slab- on-grade foundations. Structural loads for these facilities have not been developed at the time of this report, but foundation bearing pressures are anticipated to be less than about 500 psf for each of the three facilities. The 2010 GFS included a field investigation and laboratory testing for a gravity outlet system which would require excavation and backfill of a portion of the existing dam. This alternative was evaluated in the 2010 Feasibility Report and has been discarded as an option. However, the data collected specifically for this alternative has been retained and incorporated into this report for completeness. 1.4 PURPOSE AND SCOPE OF WORK The purpose of the two-season geotechnical exploration program was to conduct a feasibility and a design level geotechnical evaluation of the major components of the preliminary design Project. The results of the 2009 and 2010 field exploration and laboratory test programs have been combined along with information that was compiled as a part of the feasibility study to provide a basis for geotechnical engineering analysis that will be required by the design team during the course of design. This report has been developed to be appropriate for construction Contractors to review during preparation of construction bid documents. Engineering analyses conducted for this report address the following geotechnical design factors: Diversion Dam Strength parameters of the rock mass for foundation evaluation, abutment slope stability, and excavation methods Depth of excavation to reach competent rock on the foundation and abutments Stereographic projection of joints to identify predominant joint sets and evaluate the effect of jointing on rock strength and rock slope stability Hydraulic conductivity of foundation and abutment rock mass Disposal or re-use options for waste rock material Diversion Pipeline Rock strength parameters to assess slope stability and for bolting along Stetson Creek near the diversion dam Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-5 Report of Geotechnical Engineering Services – Revised Draft March 2011 Depth to bedrock in cut-and-cover portions of the pipeline alignment and required rock excavation methods Outlet Works Geotechnical parameters for the siphon intake, siphon pipeline, and diversion and siphon outlets including: foundation/bearing allowances; lateral earth pressures; cut and fill slope stability; and other traditional geotechnical parameters that will be used in design Condition assessment of the rock along the alignment of the proposed siphon outlet pipe, including the depth of highly-weathered profile, excavation method requirements, and disposal or re-use options for waste rock material (e.g. aggregate, trench backfill, road surfacing, erosion control, etc.) The specific scope of work conducted in support of this report includes the following: 2009 Work Literature review regarding the geology of the Project site, construction records, available geologic information, past FERC Part 12 Dam Safety reports and other supporting technical information. Geologic reconnaissance at the locations of the diversion dam, pipeline, and access road under consideration. Test pit explorations (5) along the alignment of the proposed gravity outlet facility (this option has since been discarded). Seismic refraction survey at the location of the potential borrow source located upstream of the right abutment of Cooper Lake Dam. Test pit explorations (4) of the potential borrow source located upstream of the right abutment of Cooper Lake Dam. Test pit explorations (2) of the potential borrow source located near the outfall of the proposed diversion pipeline. Laboratory testing of the samples collected during the test pit explorations. General assessment of the foundation and abutments of the proposed Stetson Creek diversion dam. Evaluation of the general range of depths to bedrock, rock rippability, and long-term side slope stability along the Diversion Pipeline Alignment. Evaluation of two potential aggregate borrow sources for use in concrete, pipe bedding, and road base during construction. Identification of needs for additional borrow sources. Estimation of the approximate quantity and potential uses for available borrow material at each borrow location. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 1-6 Report of Geotechnical Engineering Services – Revised Draft March 2011 2010 Work Two (2) vertical rock core borings, consisting of one at each abutment of the proposed final location of the Stetson Creek Diversion Dam. Two (2) water pressure tests, consisting of one test in each of the diversion dam bore hole. Televiewer log of bore hole B-2-2010 to record the orientation of joints, fissures, or other discontinuities in the rock mass and the overall condition of the rock. Two (2) seismic refraction lines along the axis of the proposed diversion dam, consisting of one on each abutment. Three (3) seismic refraction lines along the refined pipeline alignment (3) roughly parallel to Stetson Creek. Two (2) soil borings using mud-rotary drilling methods near the existing Cooper Lake Dam. California Modified split spoon penetration testing was conducted and soils samples obtained. Two (2) vertical rock core borings, including a televiewer log, at the location of B-5-2010 within the spillway channel. The borings were advanced using a track-mounted rotary drill rig to depths up to 30 feet below the ground surface. 1.5 REPORT STRUCTURE This report is divided into seven sections as follows: Section 1 – Introduction. This section introduces the Project and provides a description of the Project details and scope with respect to this geotechnical engineering report. Section 2 – Site Characterization. This section provides descriptions of the methods used to characterize the site. Section 3 – Site Conditions. This section presents the site conditions based on field investigations, previous work at the site by others, and readily available published data. Section 4 – Geotechnical Evaluations. This section presents a summary of the analyses, evaluation methods, and findings. Section 5 – Recommendations for Construction Observation. This section presents recommendations for geotechnical construction observation during construction of the Project. Section 6 – References. This section provides a list of reviewed Project documents and cited works. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-1 Report of Geotechnical Engineering Services – Revised Draft March 2011 2.0 SITE CHARACTERIZATION Site characterization was based on literature review and field investigations. Field investigations consisted of geologic reconnaissance, geophysical seismic refraction surveys, exploratory drilling, and test pit explorations. A summary and logs of our site explorations, laboratory testing, geophysical surveys, and selected historical exploration logs are present in Appendices I through VII. Key details and findings of our site characterization are described in the following paragraphs. 2.1 LITERATURE REVIEW Characterization of the Project site was based in part on a literature review of documents provided by Chugach, documents on file with MWH, and some publically available documents. Chugach provided documents including original design reports, available design and as-built construction plans, available FERC Part 12 and similar dam safety reports, and other Project- related documents. MWH also reviewed Project documents on-file such as the 2003 and 2008 FERC Part 12 dam safety reports and relicensing documents. Readily available USGS reports related to the site were also reviewed. A document search of the Alaska Department of Natural Resources’ database did not identify any documents applicable to the Project. A comprehensive list of the documents included in the literature review is presented in Section 6 “References” of this report. Previous subsurface evaluations of the site have included site reconnaissance, borings, trench explorations, and seismic refraction surveys. The following list indicates the known geotechnically-related site explorations in the vicinity of the planned Stetson Creek diversion and Cooper Lake outlet: 1915 – USGS conducts a reconnaissance to identify potential hydropower sites in south- central Alaska, which included an evaluation of Cooper Lake (Ellsworth and Davenport, 1915). 1955 – USGS conducts a geologic site reconnaissance of four lakes in the vicinity of Kenai Lake including Cooper Lake (Plafker, 1955). 1955 – Seven borings, four test pits, one trench and several seismic refraction surveys are conducted near the location of Cooper Lake Dam in association with the Project design (NPC, 1955). Investigations also included a reconnaissance for the potential siting of a Stetson Creek diversion system. The system included diverting water with a small gravity dam at an elevation of approximately 1,235 feet. Water would have been conveyed to Cooper Lake via an 8-foot wide canal. The preliminary canal intended to collect water from streams along the route to Cooper Lake, and was envisioned to include multiple overflow spillways to deal with precipitation events that would otherwise overwhelm the canal. The diversion system was considered infeasible at that time, presumably for financial reasons. 1965 – Fred O. Jones, the project geologist for the design of the dam, conducts the first safety review. The review includes a geologic reconnaissance and trench explorations on the upstream side of the dam (Jones, 1965). Exploration logs and site plans indicating Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-2 Report of Geotechnical Engineering Services – Revised Draft March 2011 their location were not included in the reviewed copy of the report. Significant findings of the review include areas of wave erosion, longitudinal tension cracks on the dam crest, deformation of the core material, mud spots on the crest of the dam, and a depression on the upstream face that is referred to as a “sinkhole”. The review also addresses the perceived impact of the 1964 Good Friday Earthquake on the dam. Mr. Jones makes recommendations for additional slope stability analyses and modifications to the upstream slope of the dam. 1983 – Three observation wells (piezometers) were installed to monitor groundwater levels at various locations within the dam (Stone & Webster, 1988). Exploration logs associated with the installation of the piezometers were not readily available. Details regarding the screen, filter pack, and seal intervals are not known. 2009 – MWH conducts a feasibility level evaluation of the Stetson Creek Diversion and Cooper Lake Dam Facilities Project. The study includes 12 test pit explorations, 9 seismic refraction surveys, and a preliminary geological site reconnaissance. As part of the study four diversion dam sites are identified, and a siphon outlet facility constructed through the spillway is identified as the most economically feasible option. 2.2 FIELD INVESTIGATIONS Field investigations associated with this report included the development of field investigation plans, geological reconnaissance, geophysical surveys, test pit explorations, exploratory borings, and laboratory testing. Descriptions of the field investigations and laboratory testing are described in the following paragraphs. 2.2.1 Field Investigation Plan For the 2009 work, a draft Field Investigation Plan was developed and provided to Chugach for submission to the Dam Safety Division of FERC. As part of FERC’s review process, MWH attended a meeting at FERC’s Portland, Oregon, office to discuss the Dam Safety Division’s concerns prior to the geotechnical fieldwork. As a result of this meeting, modifications were made to the Field Investigation Plan for final submittal to FERC, which excluded subsurface borings through Cooper Lake Dam and one test pit located near the toe of the dam at FERC’s request. MWH attended a second meeting with FERC dam safety officials in November 2009 to debrief FERC on the results of the field investigations and to allow for initial comments on the preliminary Project design. For the 2010 work, a similar Field Investigation Plan was provided to Chugach for submission to FERC. This investigation plan included a modification to the spillway siphon alignment, with associated locations for exploratory drilling. The 2010 Field Investigation Plan was ultimately approved by FERC in July 2010 and approval was granted to MWH to proceed with the work described herein. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-3 Report of Geotechnical Engineering Services – Revised Draft March 2011 2.2.2 Geological Reconnaissance MWH conducted a geological site reconnaissance of the proposed diversion dam location and pipeline alignment on September 22, 2009; September 25, 2009; October 7, 2009; and June 28 through June 30, 2010. The purpose of these reconnaissance visits was to evaluate and select a preferred diversion dam site, note the surface conditions at the diversion dam site alternatives, as well as along the accessible portions of the diversion pipeline, including grades and slopes, vegetation, stream crossings, and other visible geologic features. As a result of these field evaluations, the site of the Stetson Creek diversion dam and the pipeline alignment were modified from the original location proposed in early 2009 to better suit Project requirements. 2.2.3 Geophysical Survey MWH’s subconsultant, Northwest Geophysical Associates (NGA), conducted a total of nine geophysical seismic refraction surveys at the site between September 29 and October 2, 2009. These seismic refraction surveys were conducted in borrow areas, within the existing Cooper Lake Dam spillway, and along accessible portions of the diversion pipeline as it was envisioned in 2009. Locations of the 2009 seismic refraction surveys are indicated on Figure 2. Initial plans were to conduct seismic refraction surveys at the location of the diversion dam and along the diversion pipeline alignment adjacent to Stetson Creek. However, conducting seismic refraction surveys could not be conducted without the use of rope access equipment, which was not feasible within the schedule and budget constraints of the 2009 scope of work. NGA returned to the site in 2010 with appropriate gear for working on the steep slopes at the diversion site and within Stetson Canyon. Five geophysical seismic refraction surveys were conducted between July 27 and July 30, 2010. Two of the seismic refraction lines were conducted at the diversion dam site, one along the approximate centerline of each diversion dam abutment. The remaining three were conducted along the road/pipeline alignment within Stetson Canyon. Each of these three seismic lines was biased towards the uphill side of the approximate centerline to investigate the state of the cut materials. Locations of the 2010 seismic refraction surveys are indicated on Figures 2, 7,8, and 9. 2.2.4 Test Pit Explorations Test pit explorations were conducted during the 2009 site investigations at the locations of the proposed borrow areas, near the outfall of the diversion pipeline, and along the alignment of a previously considered gravity outlet through Cooper Lake Dam. Test pit explorations were used to identify and characterize subsurface conditions at these locations and to obtain soil samples for laboratory testing. A total of 12 test pits were excavated between October 5 and October 6, 2009. Test pit locations are indicated on F-3 and F-15. Test pit logs are presented in Appendix IV. 2.2.5 Exploratory Drilling A series of six subsurface borings were conducted during the 2010 site investigation. Two rock core borings were conducted at the location of the proposed diversion dam. Rock core borings Stetson Creek Diversion and Cooper Lake Dam Facilities Page 2-4 Report of Geotechnical Engineering Services – Revised Draft March 2011 were also conducted at two locations within the existing spillway channel along the alignment of the proposed siphon. Two soil borings were conducted along the alignment of the proposed siphon outlet. One of these soil borings was conducted upstream of the existing spillway near the proposed siphon intake. The other soil boring was conducted downstream of the spillway in the vicinity of the proposed butterfly valve and siphon outlet structures. The locations of the subsurface borings are presented on Figures 3 and 6. Subsurface boring logs are presented in Appendix I. 2.2.6 Laboratory Testing A laboratory testing program was developed to determine the physical and corrosion characteristics of the soil and rock encountered at the site. Disturbed grab and bulk soil samples were collected from the 2009 test pit explorations as described above in Section 2.2.4. The laboratory testing for these samples included moisture content, grain size distribution, liquid and plastic limits, and a suite of corrosion potential tests. Samples from the 2010 site investigation were collected from soil borings, rock core boring, and from surface bulk samples. Laboratory testing conducted on the soil borings included grain size analysis, moisture content, and Atterberg limits. Rock core samples were tested for unconfined compressive strength, Young’s modulus, and residual direct shear strength. Surface bulk samples from the potential borrow sources were evaluated for Los Angeles (LA) abrasion, coarse aggregate soundness, and petrographic composition. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-1 Report of Geotechnical Engineering Services – Revised Draft March 2011 3.0 SITE CONDITIONS Site conditions were explored and characterized as described in Section 2. Site conditions, based on MWH’s observations of the site including geology, surface conditions, and subsurface conditions are summarized in the following sections. 3.1 GEOLOGY 3.1.1 Regional Geology The glacially-carved mountains of the Kenai Peninsula in the Cooper Lake area summit at between 5,000 and 6,000 feet above sea level, with as much as 5,000 ft of local relief. Plafker stated “These mountains are a rugged mass with little apparent arrangement of form or drainage (1955).” Creeks of the area all drain to Cook Inlet via the Kenai River. In general, the valleys are heavily forested with spruce and an understory of alder, hemlock, birch, cottonwood, and willow up to an elevation of about 2,000 feet. Dense thickets of alder cover the range between the forest level and the more sparsely vegetated uplands. The Kenai Mountains in the Cooper Lake area are comprised of metasedimentary rocks that are likely from the Mesozoic Era. Plafker states that Quaternary glaciation has “modified the terrain and removed any chemically-altered material that may have been present up to an altitude of about 4,000 feet (1955).” Cooper Lake and several of the other local lakes are contained behind natural dams of glacial (moraines) and alluvial (outwash) materials within glacially-carved, U- shaped valleys. The crudely stratified glaciofluvial and the stratified alluvial deposits both consist of silt, sand, gravel, and boulder sediments. Talus of unstratified coarse rubble collects on the steeper slopes, a result of very common occurrences of mass-wasting (Plafker, 1955). Bedrock consists of thinly bedded metasediments of dark gray to black slate with interfingering lenticular beds of hard and massive, fine- to medium-grained graywacke (firmly indurated, angular/subangular grained, poorly sorted/well graded sandstone with dark rock/mineral fragments in compact clayey/slatey matrix, otherwise known as a dirty sandstone, typical of submarine turbidite currents). To a much lesser extent, there are interstratified lenticular bodies of conglomerate that are generally less than 10 feet thick. Locally, small veins and irregular masses of quartz can be found. Structurally, the rock has been tightly folded along a generally north-south axis and overturned to the west. Bedding attitudes in the region are somewhat variable, ranging between north-south to north 65 degrees east and dipping from 75 degrees west to 45 degrees east, but most commonly the dips are near vertical, ranging between 75 degrees west to 75 degrees east. While faulting is common, the displacement along these faults is typically covered quickly by sediments making them difficult to quantify. It is thought that much of the stress and Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-2 Report of Geotechnical Engineering Services – Revised Draft March 2011 displacement due to faulting is relieved by relatively small movements along established bedding or joint surfaces (Plafker, 1955). Jointing is typically well developed in the greywacke, while the fine-grained rock possesses an imperfect incipient cleavage that strikes essentially parallel to bedding. Two distinct, transverse sets of widely-spaced, high angle fractures are common. These conjugate joint sets “strike between east and southeast and between north and northwest (Plafker, 1955).” Given that there are many rectangular topographic features in the area, and that many of the local drainages appear to be controlled by these fractures, it appears likely that these joint sets are “probably open and constitute lines of weakness (Plafker, 1955).” A well-developed east-west striking set of vertical jointing is also common, particularly in the greywacke. 3.1.2 Seismicity Overview Regional seismicity is considered high, although no active faults are known with any certainty to be located near the Project site. The nearest possible known source of significant seismicity is the Shelikof Straight fault zone, approximately 12 miles west of the site. The Kenai Lineament, located approximately 15 miles east of the site, is also in close proximity. These features are approximately 350 and 55 miles long, respectively. The inferred trace of the Shelikof Straight fault zone has a southwest to northeast strike and extends from approximately Kodiak Island to near Palmer. This fault zone is believed to have been active in the Holocene (last 11,000 years). The Kenai Liniament includes the generally north to south valley aligned with Moose Pass, Seward, and Resurrection Bay. The Kenai Liniament is considered potentially active due to possibly-related shallow seismicity. Slightly east and parallel to the Kenai Lineament is the Placer River Fault, which offsets pre- Miocene (older than about 23 million years) Paleogene units, but for which there is no more recent record. Located about 80 miles to the northwest of Cooper Lake is the Holocene Castle Mountain Fault that is considered capable of producing moment magnitude (M) 6 to M7 earthquakes. The Aleutian Megathrust, the source of the M9.2 Good Friday Earthquake of 1964, is located about 170 miles to the southeast. Several active, relatively short faults (Johnstone, Hanning, and Patten Bay) are located in closer proximity (50 to 85 miles), but appear to have been offset during the 1964 event. The seismic records indicate that M5 to M6 events are relatively common within a 100 kilometer radius of the site. These records also indicate that M7 events have occurred within the last 111 years. Table 1 presents a list of recorded earthquakes within a 100 kilometer radius of Cooper Lake Dam that exceed a magnitude of 5.0 based on USGS National Earthquake Information Center (NEIC) records. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-3 Report of Geotechnical Engineering Services – Revised Draft March 2011 Table 1 List of Recorded Earthquake Magnitudes Date1,2 (dd/mm/yyyy) Distance From Site1,2 (kilometers) Magnitude1,2 (Moment) 07/14/1899 49 7.2 09/22/1911 46 6.9 01/27/1931 57 5.6 06/13/1933 90 6.2 06/19/1933 98 6.0 06/18/1934 65 6.7 10/11/1940 61 6.0 07/30/1941 90 6.2 09/27/1949 88 6.7 06/25/1951 75 6.2 10/03/1954 49 6.7 11/19/1958 59 5.9 06/30/1960 61 5.9 09/05/1961 91 6.1 03/28/1964 74 6.1 03/28/1964 79 5.6 03/28/1964 90 5.7 03/29/1964 76 5.5 04/26/1991 92 5.2 12/07/1991 64 5.1 05/18/1993 67 5.2 04/25/1994 88 5.4 05/24/1995 66 5.6 05/13/1997 86 5.0 12/05/1997 62 5.1 07/22/1999 99 5.3 02/09/2002 82 5.3 02/06/2002 83 5.0 07/27/2006 81 5.0 Key: 1 – Based on data from USGS/NEIC database for earthquakes between 1973 and 2010, database queried on 12/27/2010. 2 – Based on data from USGS database for significant earthquakes between 1568 and 1989, database queried on 12/27/2010. Includes magnitudes of 5.5 or Mercalli intensities of VI or greater. Events occurring prior to 1900 are assigned an epicenter based on the locations where damage occurred and magnitudes are derived from intensities for pre-instrumental events. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-4 Report of Geotechnical Engineering Services – Revised Draft March 2011 3.1.3 Local Geology Although the existing dam was built about 500 feet upstream of the location shown by Plafker, it appears that the dam is directly underlain mostly by unconsolidated glaciofluvial deposits, though alluvial sediments may lie within the former Cooper Creek channel (Plafker, 1955). The glaciofluvial deposits consist mainly of angular to subrounded, poorly-sorted, gravel, cobbles, and boulders in a sand and silt matrix. A well-developed post-glacial podsolic soil profile (severely leached and highly acidic with a gray ashy appearance; extending immediately south of tundra regions of the Northern Hemisphere, characteristically capped with an abundant surface accumulation of organic matter) often develops on the exposed ground surface, and can mark the interface with younger alluvial sediments. This soil horizon is characterized by a bleached, 1- to 2-inch thick, gray or white horizon lying immediately beneath the surficial organic horizon, and above an iron-rich, reddish-brown horizon that may be up to 2.5 feet thick. Bedrock beneath Cooper Lake Dam is fine-grained, well-consolidated, dark gray, blue-black, or black slate with minor, thin (trace to 1-inch) lenses of greywacke. Cleavage is imperfect and “the rock breaks into slabs with rough irregular surfaces (Plafker, 1955).” These slabs of slate are cut into angular pieces of 9 inches or smaller following closely-spaced cross-cutting joint planes. The slate is weathered mechanically to a depth of about 3 feet along the cleavage and joint planes. Cleavage and bedding strikes at between about north-south to north 10 degrees east and dips at between 85 degrees east and 85 degrees west. 3.2 SITE CONDITIONS 3.2.1 Surface Conditions 3.2.1.1 Diversion Dam Surface conditions at the proposed diversion dam location are characterized by a gorge with steep slopes. The natural slope of the left abutment slopes downward to the southeast at rate of 1.3 horizontal to 1 vertical (1.3H:1V), while the right abutment slopes downward to the northwest at a rate of approximately 0.8H:1V. The average grade of Stetson Creek at this location is approximately 6 percent, with localized portions exceeding 20 percent over short distances. Exposures of shallow bedrock are visible within the stream bottom and along lower portions of the slopes. Upper slopes appear to be mantled with a thin layer of overburden soil. Vegetation at the diversion dam site consists primarily of alder and tall grass. 3.2.1.2 Diversion Pipeline and Construction Access Road Surface conditions along the diversion pipeline and construction access can be divided into two reaches (Stetson Creek and Cooper Creek) divided by the ridgeline between the two drainage basins at approximate pipeline Station 37+00. The Stetson Creek reach of the diversion pipeline and construction access road alignment, located between pipeline Stations 0+00 and 37+00, is characterized by a gorge that is on the order of 200 feet deep. The southern slopes of the gorge generally dip downward toward Stetson Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-5 Report of Geotechnical Engineering Services – Revised Draft March 2011 Creek at an average rate of 1.4H:1V to the northwest. Slopes located immediately adjacent to the stream are commonly steeper than 1H:1V. Shallow bedrock can be seen within Stetson Creek and along many of the lower portions of the adjacent slopes. The upper slopes of the gorge are typically mantled with soil substrates. Surface indications of slope instability, including scars from recent sloughing and hummocks, are common along the diversion pipeline and construction access road alignment within the Stetson Creek gorge. These locations are discussed further in the “Geologic Hazards” section of this report. Vegetation along the Stetson Creek reach of the alignment is dominated by areas that alternate between alders with tall grass and stands of coniferous trees. The second reach of the diversion pipeline and access road is identified as the Cooper Creek reach. This portion of the alignment extends from pipeline Station 37+00 to the diversion outfall at Cooper Lake. The pipeline and construction access road alignment within the Cooper Creek reach transect relatively moderate to flat slopes relative to the Stetson Creek reach. Slopes within the Cooper Creek reach generally dip downward to the northeast at rates ranging from 3H:1V to 6H:1V, with steeper slopes in localized areas. Observations along this alignment revealed that shallow sloughing failures and hummocky surface topography, which can be an indicator of slope instability, are present at localized areas along the pipeline. These locations are discussed in further detail in Section 4.2.2 “Geologic Hazards” of this report. The ground surface within the Cooper Creek reach is generally covered by a thick layer of duff, with occasional bedrock outcroppings present near the location of the existing spillway. Vegetation along the Cooper Creek reach is similar to the Stetson Creek reach, varying between areas predominated by alder with tall grass and stands of coniferous trees. 3.2.1.3 Outlet Works The outlet facility is located within the Cooper Lake Dam spillway. Cooper Lake Dam is approximately 52 feet high, with a crest elevation of 1,220 feet. The crest is approximately 15 feet wide and 920 feet long. Slopes of Cooper Lake Dam are 2.5H:1V on the upstream slope, 2H:1V on the upper portions of the downstream slope, and 1.5H:1V on the lower portions of the downstream slope below the existing access road (Stone & Webster, 1988). The upstream slope is covered by a 6-inch thick, grouted erosion control apron. Rock fill material is present at the ground surface along the crest of the dam and upper portions of the downstream slope, while the lower portions of the downstream slopes are mantled with riprap. The upstream slope of the dam is void of vegetation. Vegetation on the crest and the downstream slope consists of sparse grass and low shrubs. The existing spillway is located at the left abutment of Cooper Lake Dam. The spillway is approximately 50 feet wide and nearly 600 feet long. Bedrock is located at the ground surface of the spillway, with the exception of a small earthen embankment located along the right side between siphon outlet Stations 9+70 and 10+50. The bedrock base of the spillway is situated at an elevation of 1,207 feet; however, water flow through the spillway is controlled by a 3-foot high concrete weir located approximately in-line with the axis of Cooper Lake Dam. Vegetation within the spillway is sparse and consists primarily of moss, grass, and small alders. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-6 Report of Geotechnical Engineering Services – Revised Draft March 2011 The spillway discharges into a heavily vegetated channel with alder and stands of deciduous and coniferous trees. The end of the spillway is characterized by a near vertical rock wall with a drop of approximately 10 feet into the vegetated channel. This feature can be noted near siphon outlet Station 11+25 of the siphon alignment (Figure 3). The vegetated channel extends approximately 250 feet where it intersects the natural Cooper Creek channel. 3.2.2 Subsurface Conditions Subsurface conditions at the diversion dam, along the diversion pipeline and access road, along the outlet facility, and two potential borrow areas were investigated with a series of seismic refraction surveys, test pit explorations, and exploratory drilling. The locations of each of these subsurface explorations are depicted on Figures 2, 3 and 6. A summary of the subsurface conditions encountered at these locations is presented in the following paragraphs. Exploratory 2010 drilling logs, 2010 laboratory data, 2009 test pit logs and 2009 laboratory tests results are presented in Appendices I,II,IV and V, respectively. Detailed reports of the 2010 and 2009 geophysical seismic surveys are presented in Appendix III and VI, respectively. Selected historical exploration logs were used for reference and aided in the preliminary subsurface characterization of the site. The locations of the select historical explorations are presented on Figure 3, and the original logs are included as Appendix VII. 3.2.2.1 Diversion Dam Subsurface conditions at the proposed diversion dam were evaluated by conducting two rock core explorations (B-1-2010 and B-2-2010) and two seismic refraction surveys (SL-10-1-1 and SL-10-1-2). The locations of these explorations are presented on Figure 6. Shallow rock is exposed in the streambed of Stetson Creek and in the lower elevations of each abutment. Based on observation, the rock at these locations consists of intact, moderately weathered, gray slate. The exposed moderately weathered rock is expected to be underlain by fresh to slightly weathered slate at a depth of about two feet. Explorations B-1-2010 and SL-10-1-2 were conducted on the slope of the left abutment. Explorations show that the fresh to slightly weathered slate is overlain by a layer of displaced rock that is approximately 13 ft thick. It is believed that this displaced rock is the result of a combination of factors including stress relief, freeze-thaw cycles, undercutting from Stetson Creek and slope creep. Intact, fresh to slightly weathered, moderately hard slate was encountered below the displaced rock to the depths explored of 40.4 ft. Above the proposed elevation of the diversion dam abutment, the displaced rock is mantled by a thin layer of overburden soils consisting primarily of colluvium and topsoil. Explorations B-2-2010 and SL-10-1-1 were conducted on the slope of the right abutment. Relatively low rock quality designations (RQD’s) in the upper five feet of B-2-2010 indicate the upper portions of the rock surface at this location have been somewhat disturbed. This disturbance is likely the result of both stress relief and freeze-thaw cycles. The disturbed rock was underlain by intact, fresh to slightly weathered, moderately hard slate to the depth explored Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-7 Report of Geotechnical Engineering Services – Revised Draft March 2011 of 30.0 ft. Similar to the left abutment, the rock is overlain by a relatively thin layer of overburden consisting of colluviums and topsoil at elevations above the proposed dam abutment. 3.2.2.2 Diversion Pipeline and Construction Access Road Stetson Creek Reach The Stetson Creek reach of the diversion pipeline and access road was explored by conducting a series of three seismic refraction surveys (SL10-2, SL10-3, and SL10-5) and by conducting a geologic reconnaissance. The locations of the seismic refraction surveys are depicted on Figures 2 and 7 through 9. In general, the seismic refraction surveys along the Stetson Creek reach of the diversion pipeline and access road indicate the presence of organic or poorly consolidated materials overlying slide deposits. These layers generally extend 3 to 10 feet below grade. Competent bedrock velocities were noted in SL10-2 at typical depths of 10 feet, with depths as shallow as zero feet. Bedrock velocities were noted in SL10-5 at typical depths of 50 to 60 feet. SL10-4 was eliminated from the exploration program in the field due to schedule and budget constraints. The presence of poorly consolidated slide deposits is consistent with observations made during the geologic reconnaissance. Landforms showing signs of previous slope movements are common within the Stetson Creek reach of the alignment and throughout much of the Kenai Peninsula. These areas included localized sloughing, hummocky terrain, pistol-butted trees, and historical headscarp features. Areas exhibiting landslide topography along the Stetson Creek reach are indicated on Figures 7 through 9. Cooper Creek Reach The Cooper Creek reach of the diversion pipeline and construction access road was explored by conducting a series of seven seismic refraction surveys (SL-3 through SL-9) and a geologic reconnaissance of the alignment. The locations of the seismic refraction surveys are depicted on Figure 2. Since seismic lines were completed, the alignment of the diversion pipeline and access road has been moved to accommodate the diversion dam location as well as to minimize exposure to undesirable features along the alignment, including steep slopes, wet areas, and irregular topography. However, the seismic lines conducted on the original alignment serve to sufficiently characterize the expected conditions along the revised alignment. In general, the seismic refraction surveys along the Cooper Creek reach of the diversion pipeline and access road indicate the presence of shallow bedrock mantled by a thin layer of overburden at most locations. Bedrock was typically interpreted to be approximately within about 10 feet of the ground surface or shallower. Notable exceptions to this include SL-7, where velocities characteristic of bedrock were not recorded, and SL-9, where the interpreted bedrock has a velocity that is approximately 60 percent of the average values observed at other site locations. Both SL-7 and SL-9 coincide with areas of observed hummocky topography, suggesting potential landslide deposits at these locations. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-8 Report of Geotechnical Engineering Services – Revised Draft March 2011 Interpretations of seismic velocities indicate that overburden materials likely consist of variable layers of organic material, unconsolidated sediment, and glacial till. Based on seismic velocities and observation of hummocky topographic features, it is likely that overburden soils at the location of SL-9 consist of a debris flow deposit approximately 10 feet thick. 3.2.2.3 Outlet Works Subsurface conditions at the proposed siphon outlet works were evaluated by conducting four borings (B-3-2010 through B-6-2010) and a seismic refraction survey (SL-2). Boring B-3-2010 was conducted near the siphon intake, borings B-4-2010 and B-5-2010 were conducted within the existing spillway, and boring B-6-2010 was conducted near the proposed siphon outlet. Seismic refraction survey (SL-2) was conducted within the existing spillway during the 2009 exploration program. Our subsurface characterization of the spillway area also considered information from previous borings conducted near this location (NPC, 1955). The locations of these explorations are presented on Figure 3. Subsurface conditions near the siphon intake consist primarily of medium dense sand and gravel glacial outwash deposits between the ground surface and a depth of about 28 ft. The glacial outwash deposits are visible at the ground surface extending from approximate siphon outlet Station 3+50 to the edge of Cooper Lake. Subsurface boring data indicates the glacial outwash deposits are underlain by fresh to slightly weathered, moderately hard, slate to the depth explored of 47.7 ft. Slate is visible at the surface of the existing spillway between approximate siphon outlet Stations 4+50 and 11+50. Borings B-4-2010 and B-5-2010 encountered fresh to moderately weathered and moderately hard slate from 0 to 30.0 ft in each hole. One seismic refraction survey conducted at this location indicates the underlying rock has an interpreted primary seismic velocity of 15,000 feet per second, which is consistent with sound rock. The downstream edge of the rock surface is marked by a pronounced drop off at approximate siphon outlet Station 11+50. Signs of shearing or displacement were not observed in the face of the cliff that forms this drop off suggesting that the pronounced feature could have been formed by glacial or fluvial erosion rather than by recent faulting. Boring B-6-2010 was conducted downstream of the existing spillway near the location of the proposed siphon outlet. The subsurface conditions at this location consist of medium dense sand with silt and gravel between the ground surface and a depth of 8.5 feet. The sand layer is underlain by very stiff silt and lean clay with occasional 1- to 3- inch thick gravel interbeds to a depth of 43 ft. The very stiff layer of silt and lean clay is underlain by very dense to dense sands and gravels to the depth explored of 50.5 ft. 3.2.2.4 Potential Borrow Sources The subsurface conditions of two potential borrow sources for possible use as construction aggregate were explored by excavating six test pits and one seismic refraction survey during the 2009 site investigation. The Right Abutment Borrow Source is located upstream of Cooper Lake Dam’s right abutment (Figures 2 and 3). It is presumed that this borrow source was used for fill Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-9 Report of Geotechnical Engineering Services – Revised Draft March 2011 material during the construction of the dam. The Outfall Borrow Source is located along the shoreline of Cooper Lake near the proposed outfall of the diversion pipeline (Figures 2 and 3). This borrow source could potentially extend from the upstream edge of the existing spillway to an alluvial fan near Test Pit TP-9. A summary of the conditions encountered at both of these potential borrow sources are presented in the following paragraphs. Right Abutment Borrow Source The potential borrow source near the right abutment of the Cooper Lake Dam was explored by excavating Test Pits TP-4 through TP-7 and conducting seismic refraction Survey SL-1. The near surface soil at TP-4, TP-5, and TP-6 consist of dense, poorly-graded sand with gravels, cobbles, and boulders and well-graded gravel with sand and boulders. The maximum boulder size encountered at this location was 14 inches in diameter. This soil unit was present at a depth of 2.5 feet in TP-7. The sand and gravel soils extend to depths of 10 and 11 feet in TP-6 and TP-7, respectively, and were present throughout the entire depths of TP-4 and TP-5. Moisture content of the sand and gravel ranges from 4 to 8 percent, with a fines content of approximately 8 percent. Near surface soil at Test Pit TP-7 consist of a 2.5-foot layer of organic topsoil consisting of low plasticity silt. This organic silt has a moisture content of 61 percent, based on one sample. The sand and gravel soil units that predominate the surface conditions of this borrow area are underlain by dense to very dense silty sand with varying amounts of gravel in explorations TP-6 and TP-7. This silty sand unit is present at depths of 10 and 11 feet in TP-6 and TP-7, respectively. The silty sand unit is present to the depth explored in both of these test pits. The silty sand has a moisture content ranging from 11 to 12 percent, based on two tests. Water was encountered in each of the test pits conducted in this borrow area. The depths where water was encountered ranged from 4 feet bgs in TP-6 to 10.4 feet bgs in TP-5. Water was encountered at 9 feet bgs in TP-4 and at 6 feet bgs in TP-7. Seismic refraction Survey SL-1 was conducted along a relatively flat area extending from near TP-4 to near TP-7. The results of this survey indicate that the soil profile within the Right Abutment Borrow Source extends to a depth of approximately 50 to 60 feet bgs. Outfall Borrow Source The second potential borrow source is located along the western shore of Cooper Lake in the vicinity of the diversion pipeline outfall. The subsurface conditions at this location were explored by excavating Test Pits TP-8 and TP-9. Medium dense, poorly-graded gravel with sand and cobbles was the only soil unit encountered in TP-8. This test pit was terminated at 11 feet bgs due to refusal on a large boulder. This soil unit had a moisture content that ranged from 2 to 7 percent and a fines content of 1 percent. Soils encountered in TP-9 consisted of medium dense, poorly-graded sand with gravel and cobbles to the depths explored. This test pit was terminated at 13 feet bgs due to excessive Stetson Creek Diversion and Cooper Lake Dam Facilities Page 3-10 Report of Geotechnical Engineering Services – Revised Draft March 2011 caving. The moisture content of the poorly-graded sand ranged from 5 to 8 percent based on two samples. Groundwater was encountered in both TP-8 and TP-9 at 10 and 8.5 feet bgs, respectively. Based on visual observations, these groundwater levels corresponded closely with the elevation of Cooper Lake at the time of the explorations. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-1 Report of Geotechnical Engineering Services – Revised Draft March 2011 4.0 GEOTECHNICAL EVALUATIONS 4.1 OVERVIEW This section describes our geotechnical engineering evaluation and design recommendations for the Project. These evaluations and recommendations were based on our site investigations, local engineering practice, and the observed soil and rock properties. 4.1.1 Key Geotechnical Concerns The Stetson Creek Diversion and Cooper Lake Dam Facilities Project is considered generally feasible from a geologic and geotechnical standpoint. However, there are of a number of geotechnical concerns with the Project that may have a significant impact on capital costs or construction timelines. Some of the key geotechnical concerns include: Diversion Site Access – The proposed diversion dam is located within a steep canyon. Significant cuts will be required to construct a diversion dam construction access road capable of supporting construction equipment. These cuts will result in the excavation and removal of a large volume of earth and rock. Steep Slopes – Steep slopes are present in numerous locations throughout the Project site. Locally unstable slopes could potentially impact the proposed development if not properly mitigated. The use of horizontal drains, trench drains, and maintaining safe cut and fill slope angles will be required to limit the impact of naturally steep and potentially unstable areas on the Project improvements. Controlled Rock Excavation – The proposed siphon outlet will be constructed through the existing rock spillway of Cooper Lake Dam. Heavy or uncontrolled blasting could potentially damage the rock formation and negatively impact the integrity of the dam. Controlled blasting is recommended to limit the risk of potential damage to the existing spillway facility. Underwater Structures – A number of the proposed site improvements will be located under water, or will be subjected to fluctuating water levels throughout the course of its service life. The design of these structures and Project features should be able to withstand the buoyant force of water. Further, structures and Project features should be designed or armored to withstand the erosional effects of water. Construction Dewatering – Construction dewatering and stream diversion will be required to construct a number of proposed site facilities. Design of construction dewatering and stream diversion systems will depend on a number of factors including rate of construction, use of shoring, and type of dewatering system. Construction dewatering system design is commonly and best established as the Contractor’s responsibility, as they will have control of construction means and methods. This allows the Contractor to provide a dewatering system that is compatible with their chosen construction and shoring equipment, and methods. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-2 Report of Geotechnical Engineering Services – Revised Draft March 2011 Dissimilar Foundation Materials – Based on the conditions observed in our site investigation, there is a potential of encountering dissimilar foundation materials (glacial deposits and rock) within the foundation footprint of the diversion pipeline outlet structure. If both rock and soil subgrades are encountered within the footprint of these facilities, we recommend that the rock be overexcavated and backfilled with structural fill to provide a uniform bearing surface. 4.2 GEOLOGIC HAZARD ANALYSIS AND RECOMMENDATIONS A number of geologic hazards, including earthquake related hazards, debris flows, and landslides could potentially impact the Project area. The following subsections present these potential hazards. 4.2.1 Seismic Hazards In addition to the direct effects on structures, strong ground shaking from earthquakes can also produce other side effects that include surface fault rupture, soil liquefaction, seismically induced settlement, lateral spreading, and seiches. 4.2.1.1 Surface Rupture Based on a review of available geologic maps, they are no known active faults that transect the Project area. The Shelikof Straight fault zone is the closest fault with suspected activity, which is located approximately 12 miles west of the site (Plafker et al. 1993). The Kenai Lineament is also in close proximity to the site, approximately 15 miles to the east. Based on the available data, the potential for surface rupture resulting from the movement of a previously unrecognized site is not known with certainty but is considered low. 4.2.1.2 Liquefaction Potential Soil liquefaction is a phenomenon that occurs when saturated cohesionless soil layers, located with about 50 feet of the ground surface lose strength during cyclic loading caused by earthquakes. During the loss of strength, the soil layer can be subjected to both lateral and vertical movements. Soils that are most susceptible to liquefaction are clean, loose, and uniformly graded, fine grained sands below the groundwater surface. The factors known to influence liquefaction potential include soil type, depth, grain size, density, groundwater level, degree of saturation, and duration and magnitude of ground motions. The soil at the site generally consists of medium dense to dense sand and gravel, and stiff silt. Accordingly, the risk of liquefaction at the site is considered low. 4.2.1.3 Seismically Induced Settlement Earthquake induced settlement typically occurs as a result of compression of underlying loose soil layers due to liquefaction or densification resulting from strong ground motions. This phenomenon can potentially cause uneven settlement of the ground surface in both saturated and Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-3 Report of Geotechnical Engineering Services – Revised Draft March 2011 unsaturated soil. Given the relatively dense and stiff soils encountered at the site, the risk of seismically induced settlement is considered low. 4.2.1.4 Lateral Spreading Seismically induced lateral spreading involves horizontal movement during an earthquake due to ground failure of the subsurface layers, typically associated with liquefaction. Lateral spreading typically occurs in saturated, loose, unconfined sedimentary and fill deposits that are adjacent to steep slopes, or in materials that overly these deposits. As a result of the failure, the overlying soil mass displaces laterally toward a free face. Given the low potential for soil liquefaction at the site, the risk of lateral spreading is correspondingly low. 4.2.1.5 Seiches Seiches are large waves generated in enclosed bodies of water due to tectonic offsets within the water body or by long-period seismic waves that match the natural frequency of the water body. Since there are no known active faults that transect the site, the risk of seiches due to tectonic offset is considered low. The risk of seiches due to harmonic oscillation within Cooper Lake or the proposed reservoir behind the Stetson Creek diversion dam are not known for certain, but are considered low. 4.2.2 Geologic Hazards Potential geologic hazards were identified at various locations along the access road alignment, as indicated on Figures 2 and 7 through 12. Steep slopes showing signs indicative of localized and shallow slope failures were observed in the field along the diversion pipeline alignment between approximate Stations 0+50 and 6+50 and near Station 8+00. Based on observations made along Stetson Creek, shallow slope failures are common. These observations are substantiated by topographic data including the presence of hummocky topography near Stations 12+00, 19+00, and 30+00. The pipeline alignment transects additional areas of hummocky topography within the Cooper Creek reach of the diversion pipeline alignment near Stations 49+00 and 78+00. The Project improvements are not anticipated to have a significant impact on the large scale slope stability of the site; however, the overall risk of slope instability is considered moderate, similar to the existing site conditions. It is likely that additional slope movement will occur over the design life of the Project. Recommended mitigation measures are discussed in Section 4.3.5 “Diversion Pipeline and Construction Access Road”. An active rock glacier was observed at approximately 1,400 ft above the diversion pipeline outfall. This rock glacier is a slowly moving mass of rock that is susceptible to mass wasting events such as sloughing of the toe, debris flows, and rock avalanches. Over geologic time, this rock glacier will likely produce debris flows and rock avalanches that will run out through the drainage that feeds the alluvial fan where the diversion pipeline outfall is located. While it is considered a very low risk to the diversion pipeline outfall, there is a slight risk for mass wasting events near the outfall of the diversion pipeline following very high precipitation events or during large earthquakes. If this event were to occur, it is most probable that the debris from the Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-4 Report of Geotechnical Engineering Services – Revised Draft March 2011 rock avalanche would come to rest approximately 500 feet southeast of the conceptual pipeline outfall location. 4.3 GEOTECHNICAL ENGINEERING EVALUATIONS 4.3.1 General Based on the results of our field investigations, laboratory testing, engineering analysis and judgment, it is our professional opinion that the construction of the proposed Stetson Creek Diversion and Cooper Lake Dam Facilities Project is feasible from a geotechnical standpoint. Our recommendations for the proposed Project facilities are presented in the following sections. 4.3.2 Seismic Design Considerations The spectral response accelerations for the site were determined in accordance with the 2009 International Building Code (IBC) using the USGS Seismic Hazards Curves and Uniform Hazard Response Spectra application Version 5.0.9a. The results of the analysis including site classifications, short period (0.2 second) spectral response, and 1-second spectra response for a 2 percent exceedance in 2,475 years in accordance with the IBC for each of the major Project components are summarized in Table 2. Table 2 Summary of 2009 IBC Seismic Design Paramters Site Site Class Ss1 (g) (0.2 Second Period) S11 (g) (1.0 Second Period) Diversion Dam B 1.773 0.657 Diversion Pipeline Outlet2 C 1.779 0.660 Siphon Intake2 C 1.778 0.660 Siphon outlet / Butterfly Valve D 1.185 0.660 Key: 1 – Ss and S1 are based on values for a Site Class B. These values should be adjusted during design based on site class in accordance with the 2009 IBC. 2 – Site class can be adjusted to B if structure is founded directly on rock. 4.3.3 Diversion Dam Foundation Design 4.3.3.1 Dam Foundation Excavation and Preparation Extensive foundation preparation will be required to provide adequate foundation support and abutment stability for the dam. The final foundation surface should consist of intact, fresh to slightly weathered, moderately hard slate with a uniform surface lacking protrusions or overhangs greater than one foot. All soil, debris, organic material, loose, disturbed, or moderately to highly weather rock, or other deleterious material should be removed from the location of the dam footprint and from areas located within 5 ft of the dam. Based on Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-5 Report of Geotechnical Engineering Services – Revised Draft March 2011 observations and subsurface data, it is expected that excavation depths will be on the order of 13 ft near the upper portions of the left abutment, 2 ft near the base of the stream, and 5 ft in the area of the right abutment. Excavated slopes should be limited to 0.5H:1V. Passive rock bolts and horizontal drains will be required to maintain this slope in rock excavations outside the footprint of the dam. These rock bolts and horizontal drains should be installed in accordance with the “Permanent Slopes” section of this report. Once excavations are complete, the dam foundation surface should be thoroughly cleaned to allow for inspection and mapping of the dam foundation. The foundation should be cleaned using picks, crowbars, shovels, brooms, air hammers, low pressure air or water, or other approved cleaning tools. Areas of soft, disintegrated, or otherwise unsuitable rock should be identified by a qualified geologist or geotechnical engineer during the mapping process. In addition, the mapping should identify any open or infilled joints, seams, faults, cracks, holes, cavities, or other features that would require dental excavation and treatment. Features that require dental treatment should be excavated to a depth of three times the width of the feature. Excavation should be backfilled with dental grout to match existing grades. 4.3.3.2 Dam Foundation Design Parameters The proposed diversion dam can be supported by undisturbed, intact, fresh to slightly weathered, moderately hard slate. Based on recent explorations of the diversion dam site, we anticipate that approximate excavation depths of 5 ft at the right abutment, 2 ft at the center of the stream, and 13 ft from the left abutment will be required to remove overburden soils, and disturbed or weathered rock. The diversion dam can be designed with an allowable bearing capacity of 12,000 pounds per square foot. This load may be increased by one third to 16,000 pounds per square foot when considering short term live loads such as earthquake and wind loads. A rock mass modulus of 4000 ksi can be used in the design of the dam foundation. Lateral loads can be resisted along the base of the dam using a coefficient of friction of 0.48. For the load conditions described within this report, total settlement of the diversion dam is expected to be less than ¼-inch. 4.3.4 Foundation Design Parameters for Other Facilities Structures associated with the diversion pipeline and the outlet works will likely consist of shallow spread or continuous footings, or slab-on-grade foundations. Subsurface conditions located upstream of the existing Cooper Lake Dam are expected to be comprised of glacial outwash deposits overlying shallow rock. Conditions downstream of the spillway are expected to consist of over 50 feet of silt with interbeds of gravel, sand and cobble. Accordingly, our recommendations for facilities located upstream of the dam (the diversion pipeline outlet and the siphon intake) and the facilities located downstream of the spillway (the butterfly valve structure and the siphon outlet structure) are presented separately in the following sections. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-6 Report of Geotechnical Engineering Services – Revised Draft March 2011 4.3.4.1 Diversion Pipeline Outlet and Siphon Intake Foundations Based on the results of our subsurface explorations the siphon intake will be founded on glacial outwash and the diversion pipeline outlet will be founded near the interface of the glacial outwash and the underlying rock. As a result, the potential for three foundation conditions are foreseen at the diversion pipeline outlet: 1) a subgrade comprised entirely of glacial outwash; 2) dissimilar foundation materials comprised of both rock and glacial outwash; and 3) a subgrade comprised entirely of rock. Recommendations for these conditions are presented in the following paragraphs. If the second condition is encountered (both glacial outwash and rock are present), we recommend over-excavating the rock foundation to a depth of two feet below finish grade. The resulting excavation should be backfilled with structural fill to provide a more uniform bearing surface as depicted on Figure 17. The foundations should then be designed in accordance with the recommendations presented for glacial outwash materials. The proposed diversion pipeline outlet and siphon intake, as well as any associated cast-in-place retaining walls can be supported by shallow continuous footings founded on native, undisturbed, medium dense to dense, granular, glacial outwash or structural fill placed on this material. The proposed diversion pipeline outlet and siphon intake may also be constructed on a slab-on-grade foundation founded on these materials. Shallow continuous or spread footings bearing on native, medium dense to dense, granular, glacial outwash soils or structural fill placed on this soil should be proportioned for an allowable bearing pressure of 3,500 psf. The bearing pressure applies to the total of dead and long-term live loads and may be increased by one-third to 4,650 psf for short-term loads such as those resulting from wind or seismic forces. For frost protection, slab-on-grade foundations should have a minimum depth of 34 inches and spread or continuous foundations should have a minimum depth of 62 inches below the lowest adjacent grade when not founded directly on rock. For the load conditions described in this report, total settlement of footings is anticipated to be less than 1 inch with differential settlement on the order of one-half of the total settlement. Slab-on-grade foundations supporting up to 1200 psf areal loading can be obtained from structural fill placed on undisturbed, native, medium dense sand with silt. This load may not be combined with other shallow foundation or fill loads. In our opinion, a subgrade reaction modulus of 250 pounds per cubic inch can be used for the design of the slab-on-grade foundation. The anticipated settlement of the slab-on-grade foundation is not expected to exceed 1 inch. Foundations bearing directly on rock can be proportioned for an allowable bearing capacity of 5,000 psf. The bearing pressure applies to the total of dead and long-term live loads and may be increased by one-third to 6,650 psf for short-term loads such as those resulting from wind or seismic forces. For the load conditions described in the introduction to this report, total settlement of footings is anticipated to be less than 1 inch with differential settlement on the order of one-half of the total settlement. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-7 Report of Geotechnical Engineering Services – Revised Draft March 2011 4.3.4.2 Siphon Outlet and Butterfly Valve Structure Foundation The proposed siphon outlet structure and butterfly valve structure, as well as cantilever retaining walls can be supported by shallow continuous footings founded on native, undisturbed, medium stiff to stiff silt, or structural fill placed on this soil. The proposed structures may also be constructed on a slab-on-grade foundation founded on these materials. Shallow continuous or spread footings bearing on native, medium dense to dense, granular, glacial outwash soils or structural fill placed on this soil should be proportioned for an allowable bearing pressure of 1,500 psf. The bearing pressure applies to the total of dead and long-term live loads and may be increased by one-third to 2,000 psf for short-term loads such as those resulting from wind or seismic forces. For frost protection, slab-on-grade foundations should have a minimum depth of 34 inches and spread or continuous foundations should have a minimum depth of 62 inches below the lowest adjacent grade. For the load conditions described in this report, total settlement of footings is anticipated to be less than 1 inch with differential settlement on the order of one-half of the total settlement. Slab-on-grade foundations supporting up to 500 psf areal loading can be obtained from structural fill placed on undisturbed, native, medium dense sand with silt. This load may not be combined with other shallow foundation or fill loads. In our opinion, a subgrade reaction modulus of 150 pounds per cubic inch can be used for the design of the slab-on-grade foundation. The anticipated settlement of the slab-on-grade foundation is not expected to exceed 1 inch. 4.3.4.3 General Foundation Recommendations All shallow and slab-on-grade foundations should be designed in accordance with the 2009 International Building Code (IBC). A qualified geotechnical engineer should observe the subgrade to verify that the exposed subgrade will support anticipated loads before backfilling the resulting excavation or casting footings. Soil that is soft, disturbed, or is yielding based on the Geotechnical Engineer’s observation should be excavated and replaced with structural fill. Footings should not be cast on loose, soft, frozen soil, slough, debris, or surfaces covered by standing water. We recommend that base rock be placed between the slab-on-grade and soil subgrades to provide a smooth bearing surface. The base rock should be a minimum of 6 inches thick and consist of aggregate that is well-graded from coarse to fine, contains no organic matter or debris, has a maximum particle size of 1½ inches, and has less than 5 percent passing the U.S. Standard No. 200 Sieve. The base rock should be placed and compacted in accordance with the “Structural Fill” section of this report. Base rock is not required for foundations cast directly on undisturbed rock. Water and groundwater levels are expected to fluctuate in response to rain events, power demands, and the volume of water diverted into Cooper Creek. As a result, the proposed foundations will be subjected to variable water and groundwater fluctuations. These facilities are expected to be submerged under typical or periodic loading conditions. Accordingly, the Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-8 Report of Geotechnical Engineering Services – Revised Draft March 2011 proposed structures should be designed to withstand variable water levels, including wet and dry conditions resulting from typical use and maintenance. 4.3.4.4 Lateral Loads on Buried Foundation Walls Our cantilever retaining wall design recommendations assume that the walls consist of conventional, cantilevered retaining walls or embedded building walls that are less than 20 ft in height, and the wall backfill consists of granular, free-draining gravel or sand material compacted as structural fill. Given the site elevations and the depth of the proposed facilities, some walls will be located below groundwater elevation and will be subjected to hydrostatic forces. Re-evaluation of our recommendations will be required if the Project retaining walls vary from these assumptions. In general, cantilever retaining walls yield under lateral loads and should be designed with active lateral earth pressure. Restrained walls, such as embedded building walls and vaults should be designed to withstand at-rest lateral earth pressure. These pressures act over the entire back of the wall and vary with the back slope inclination. Our recommendations for lateral earth pressures are presented on Figure 17. When computing lateral loads, a coefficient of friction of 0.42 can be used for shallow footings poured directly on structural fill. When founded directly on intact, fresh to slightly weathered, moderately hard slate, the coefficient of friction can be increased to 0.48. Wall drains should be installed in locations where gravity drains are feasible. Where drainage is not feasible, walls should be designed to resist hydrostatic forces. Wall drains should consist of a perforated pipe embedded in a minimum 1-ft wide zone of drain rock that is wrapped in a geotextile filter and sloped to drain toward a suitable outfall. The drain rock should consist of course sand or gravel containing not more than 3 percent fines (material by weight passing the U.S. Standard No. 200 Sieve by washed analysis). The geotextile filter should be a non-woven fabric with an apparent opening size (AOS) between the U.S. Standard No. 70 and No. 100 Sieve size and a water permittivity of greater than 1.5 sec-1. Backfill for retaining walls should extend a horizontal distance of H, where H is the wall height, and should consist of medium sand, sand and gravel, or well-graded sand or gravel, with not more than 5 percent fines. Geotextile filter fabric should be placed between the granular materials and the native soil to prevent migration of fines into the clean granular material. Backfill should be placed and compacted to 92 percent of the maximum dry density, as determined by ASTM D1557, with the exception of backfill placed immediately adjacent to walls. To reduce pressure on the walls, backfill located within a horizontal distance of 3 ft from the retaining walls should be compacted to approximately 90 percent of the maximum dry density, as determined by ASTM D1557. Backfill placed within 3 ft of the wall should be compacted in lifts less than 6 inches thick using hand-operated tamping equipment (such as a jumping jack or vibratory plate compactor). If flat work (slabs, sidewalk, or pavement) will be placed adjacent to the wall, we recommend that the upper 2 ft of fill be compacted to 95 percent of the maximum dry density, as determined by ASTM D1557. Settlements of up to 1 percent of the wall height commonly occur immediately adjacent to the wall as the wall rotates and Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-9 Report of Geotechnical Engineering Services – Revised Draft March 2011 develops active lateral earth pressures. Consequently, we recommend that construction of flat work adjacent to retaining walls be postponed at least four weeks after construction or until survey data indicates that settlement is complete. Static lateral earth pressures acting on a retaining wall should be increased to account for surcharge loadings resulting from any traffic, construction equipment, material stockpiles, or structures located within a horizontal distance equal to the wall height. The retaining wall design parameters provided above are not intended for use in designing mechanically stabilized earth (MSE) or un-reinforced concrete masonry unit (CMU) retaining walls. 4.3.5 Diversion Pipeline and Construction Access Road The diversion pipeline and construction access road transect a number of locations that exhibit signs of shallow seated landslides and hummocky topography indicating historical slope movements. It is likely that further slope movement will occur at these locations over the design life of the Project. To mitigate the impacts of these movements on the diversion pipeline, it is recommended that the final design of the pipeline include flexible couplings to allow for deflection of the pipeline at the locations marked as having hummocky topography on Figures 7 through 12. Shallow seated landslide topography was observed along the pipeline and construction access road between Stations 0+50 and 6+50 and near Station 8+00. The shallow seated landslides in this area are expected to be controlled primarily by fluctuations in groundwater levels. Accordingly, it is recommended that trench drains be installed at these locations in accordance with the recommendations presented in Section 4.4.4.2 “Trench Drains” of this report. 4.3.6 Permanent Slopes Permanent cut slopes in the glacial till and outwash deposits can be constructed at 2H:1V. Permanent cut slopes in the undisturbed native silt and clay soil observed downstream of the spillway should be limited to 2.5H:1V. Fill slopes constructed in accordance with the “Structural Fill” sections of this report should not exceed a grade of 2H:1V. Recommendations for permanent cut and fill slopes assume structural loads will not be located within 10 ft of the slope face. The slopes should be planted with appropriate vegetation or armored with riprap to provide protection against erosion. Surface water runoff should be collected and directed away from slopes steeper than 3H:1V to prevent water from running down the face of the slope. MWH assessed rock slope stability using RocScience SWedge® version 5.002 software based on observed joint and bedding orientations. Based on the results of this analysis rock slopes can be cut as steep as 0.5H:1V provided that the slopes are reinforced. The analysis included passive rock bolts installed on 8-ft centers with a working load capacity of 40 kips and a plunge (dipping downward into the slope) of 10 degrees. Rock slope stability should be confirmed once the final design of the rock bolts has been completed. Further, field testing of rock bolts is recommended to confirm rock bolt design capacities. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-10 Report of Geotechnical Engineering Services – Revised Draft March 2011 Fill slopes should be founded directly on undisturbed native soil subgrade. Fill slopes constructed on slopes steeper than 3H:1V should be benched into the existing native ground for a distance of at least 10 feet and should be keyed into undisturbed native soil at the toe of the slope to a depth of 2 feet bgs as shown on Figure 17. A 4-inch diameter perforated pipe drain should be placed at the base of constructed slopes over 4 ft in height and wherever seepage is observed. All perforated pipe drains should be directed to a suitable discharge. The perforated pipe drain should be enveloped with uniformly graded drain rock with a maximum particle size of 1-1/2 inches, having no more than 3 percent passing the U.S. Standard No. 200 Sieve (wet wash method). The drain rock should extend at least 12 inches on all sides of the pipe. The gravel envelope should be wrapped with geotextile filter fabric to reduce the migration of fines from the surrounding soil into the drain. The geotextile filter should be a non-woven fabric with an AOS between the U.S. Standard No. 70 and No. 100 Sieve size and a water permittivity of greater than 1.5 sec-1. Horizontal drains should be installed at locations where seepage is encountered in cut slopes steeper than 3H:1V and in all permanent rock excavations steeper than 1.5H:1V in accordance the “Horizontal Drains” section of this report. 4.3.7 Excavation Evaluations 4.3.7.1 General An analysis of potential rock excavation methods was conducted for the diversion dam, the diversion pipeline and the siphon outlet. The analyses were based on rock velocities obtained from the seismic refraction surveys conducted at these locations. The excavation analysis was conducted following the methods outlined by the U.S. Army Corps of Engineers (USACE, 1983) using the most recent equipment updates provided by the Caterpillar Performance Handbook (Caterpillar, 2009). Our analysis was based on the performance statistics for a Caterpillar D8R or D8T bulldozer with a multi or single shank No. 8 ripper. 4.3.7.2 Diversion Dam Seismic refraction surveys conducted along the axis of the diversion dam indicate an upper layer of overburden and disturbed rock overlying more intact rock. Velocities for the overburden and disturbed rock layer have a seismic velocity of 300 to 400 feet per second (fps). This material is considered rippable. The rock underlying the right abutment has an interpreted seismic velocity of 4,200 fps. The velocity indicates that this rock is rippable. Interpreted seismic velocities of the left abutment were 7,000 fps, indicating marginally rippable rock. 4.3.7.3 Diversion Pipeline and Construction Access Road Based on the seismic refraction surveys conducted along the Cooper Creek reach or the diversion pipeline and access road alignment, bedrock is commonly located within 10 feet or less of the existing ground surface. Seismic refraction surveys indicate the depth to rock along the Stetson reach or the diversion pipeline and access road is highly variable. Where encountered, the depth Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-11 Report of Geotechnical Engineering Services – Revised Draft March 2011 to rock at the locations surveyed ranged from 0 to approximately 60 feet bgs. The seismic velocity of the overlying soil ranged from 1,000 to 2,800 fps. These velocities indicate that the overlying soil is rippable. Interpreted seismic velocities of the underlying rock ranged from 8,600 to 13,000 fps. These velocities indicate that this bedrock is not rippable. It is expected that drilling and blasting techniques will be required to excavate trenches and road benches at many locations along the proposed diversion pipeline and access road alignment. 4.3.7.4 Outlet Works Based on a single seismic refraction survey conducted within the spillway (SL-2), the bedrock has an interpreted seismic velocity of 15,000 fps. This seismic velocity indicates that this bedrock is not rippable as defined by the USACE and Caterpillar guidelines. Accordingly, controlled drilling and blasting techniques will be required to excavate rock within the spillway. Blasting within the existing Cooper Lake Dam spillway should be carefully controlled and monitored to limit the potential damage to the rock formation. We recommend that an initial maximum velocity due to blasting be limited to accepted guidelines to limit the potential damage to rock that is to remain in place. 4.3.8 Borrow Sources Two potential borrow sources were identified and explored during the first season of geotechnical work. Selected samples were collected from the test pit excavations at that time. An additional three bulk samples were collected at the ground surface at the proposed borrow areas for additional aggregate testing as part of the 2010 field investigations. The bulk samples were subjected to additional testing and examination to help determine their suitability for use as construction aggregates. The results of the current aggregate testing program and a summary of the previous evaluation of the borrow areas are presented in the following sections. 4.3.8.1 Borrow Material Properties and Volume Based on observations and laboratory testing, the two potential borrow sources investigated consist of poorly-graded sand and poorly- to well-graded gravels – with varying amounts of cobbles and boulders. This material is suitable for use in applications such as structural and common fill if processed to remove oversized and minor amounts of deleterious materials. Once processed, the borrow source aggregates may be suitable for concrete aggregate provided they meet the strength and characteristic requirements of the concrete mix designs for the Project. Volume calculations of the potential borrow areas near the right abutment and the diversion outfall have been conducted based on available topographic data using AutoCAD Civil 3D software by assuming a base excavation elevation of 1,182 feet. This elevation was selected based on the observed groundwater elevation at the time of the test pit excavations. Additional borrow material may be realized if dewatering techniques are implemented, or if the reservoir elevation is lowered. Calculations indicate the in-place volume of potential borrow material within the right abutment borrow source is as much as 70,000 cubic yards from above the Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-12 Report of Geotechnical Engineering Services – Revised Draft March 2011 anticipated groundwater elevation. An additional 9,500 cubic yards could be mined from the outfall borrow source. 4.3.8.2 Petrographic Evaluation of Aggregates A thin-section petrographic evaluation was conducted on Bulk Sample No. 2, which was collected upstream of the existing spillway. The evaluation was conducted by Terra Firma Testing of Anchorage, Alaska. A report of this analysis is presented in Appendix II. The results of the petrographic evaluation indicate that the aggregate is comprised of a calcarious, fine grained, deformed sandstone (slate). The sample was estimated to consist of about 50 percent calcite, 35 percent angular to subrounded strained detrital quartz, and minor amounts (6 percent or less) of feldspar, muscovite and sericite, opaques (magnetite, ilmenite/leucoxene, limonite, hematite), and other occasional constituents. The evaluation noted some low level metamorphism; however, the specimen still exhibits sedimentary textures. As noted above, the aggregates are primarily comprised of calcite, which is a relatively soft mineral. Additional evaluations should be conducted to determine if the aggregate meets the requirements of the specific concrete mix designs required for the Project. The aggregate also contains a significant amount of strained detrital quartz. If not properly mitigated, strained quartz in concrete can potentially lead to alkali-silica reaction (ASR). ASR can cause expansion of concrete resulting in major structural damage. The effects of ASR can be mitigated with certain pozzolans and through proper concrete mix designs. Further testing of the aggregates from the potential borrow areas should be conducted and reviewed by a qualified concrete expert to assess the need for pozzolans in the Project mix designs. 4.3.8.3 Aggregate Abrasion and Soundness Testing Aggregates from the potential borrow sources were collected and tested for abrasion and soundness. Laboratory test results are presented in Appendix II of this report. A summary of these test results is presented below. Bulk Sample No. 1 was collected from the potential borrow area near the diversion pipeline outfall. A Los Angeles abrasion test was conducted on this sample, which resulted in a loss of 22 percent. This result meets the ASTM C33 requirements of not exceeding 50 percent loss for Class 4S structures (includes waterfront structures exposed to frequent wetting in severe weathering regions). Bulk Sample No. 3 was collected from the potential borrow area upstream of the right abutment of the existing dam. This sample was tested for soundness in accordance with ASTM C88, resulting in a loss of three percent over five test cycles. This result meets the requirements of ASTM C33 of 18 percent for Class 4S structures. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-13 Report of Geotechnical Engineering Services – Revised Draft March 2011 4.3.8.4 Soil Corrosion Potential Corrosion testing was conducted on a total of four selected soil samples from the potential borrow sources as part of our 2009 site investigation. Samples were tested for parameters including pH, specific conductivity (inverse of resistivity), chloride, sulfate, sulfide, oxidation/reduction potential, and corrosivity. The results of the corrosion testing are summarized in Table 3. Testing details are presented in Appendix V. In general, the test results indicate the borrow materials have a low potential for corrosion based on each parameter analyzed. Accordingly, the borrow sources explored are suitable for concrete aggregate and pipe backfill with respect to corrosion potential. Table 3 Corrosion Testing Results Sample pH (pH units) Specific Conductivity (µS/cm) Chloride (mg/Kg) Sulfate (mg/Kg) Sulfide (mg/Kg) Oxidation- Reduction Potential (mV) Corrosivity (pH units) Test Pit Depth (ft) 4 2 5.84 ND ND ND ND 438.8 5.99 7 4 6.78 ND ND ND ND 390.0 6.98 8 2.5 6.18 ND ND ND ND 401.4 6.81 9 12.5 6.70 ND ND ND ND 391.4 6.80 Key: µS/cm – microSiemens per centimeter ft – feet mg/Kg – milligrams per kilogram mV – millivolts ND – not detected 4.4 CONSTRUCTION CONSIDERATIONS 4.4.1 Site Preparation Overburden soil, vegetation, disturbed rock, and weathered rock should be removed to expose fresh, undisturbed, and intact rock in the foundation area of the proposed diversion dam and from areas located within five feet of the diversion dam. Based on our recent explorations, we anticipate that the depth of excavation for the diversion dam will be approximately 2 ft at the base of Stetson Creek, 5 ft at the right abutment, and 13 ft at the left abutment. Unsuitable soil including fill, disturbed soil, organic soil, or soil that contains deleterious material should be stripped and removed from all other structural areas including proposed intake and outlet foundations, retaining walls, and fill slopes. The removal of these soils should extend for a five-foot margin around such areas. Excavated unsuitable soil should be replaced with structural fill to meet proposed subgrade elevations. Stripping depths are generally expected to range from 8 to 18 inches to remove roots and organic debris, although greater stripping depths may be required to remove localized zones of organics or heavily rooted soil. The actual stripping depth should be based on field observations at the Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-14 Report of Geotechnical Engineering Services – Revised Draft March 2011 time of construction. Stripped material should be transported off site for disposal or used in landscaped areas. Trees, shrubs, brush, and other vegetation should be removed from all structural areas. Organic debris and roots should be removed entirely from the diversion dam area. In other structural areas, root balls should be grubbed out to a depth such that all roots or parts of roots greater than ½-inch in diameter are removed. The depth of excavation to remove root balls of trees could exceed 3 ft bgs. Depending on the methods used, considerable disturbance and loosening of the subgrade could occur during site grubbing. Soil disturbed during grubbing should be removed to expose firm undisturbed subgrade. Where appropriate, the resulting excavations should be backfilled with structural fill. A qualified geotechnical engineer should observe the exposed subgrade and excavations after stripping, grubbing, and site cutting have been completed to identify any areas of unsuitable soil. The Geotechnical Engineer will observe a proofroll of these areas with a fully-loaded dump truck or suitable substitute when space constraints dictate. Areas of soft soil or excessive yielding should be excavated and replaced with structural fill. Proofrolling of the subgrade should not be performed during wet weather or if wet ground conditions exist to avoid disturbing the subgrade. Soil or rock that has been disturbed during site preparation activity, or soft or loose zones identified should be removed and replaced with structural fill were appropriate. 4.4.2 Temporary Slopes and Excavation Support Table 4 presents the soil types for each soil observed at the site based on the Occupational Safety and Health Administration (OSHA) classification system, provided site conditions comply with the scope and application specified by OSHA Standard 1926 Subpart P during the time of construction. All temporary excavations should be conducted in accordance with all appropriate OSHA and Alaska Department of Occupational Safety and Health (AKOSH) regulations. Surcharge loads, such as stockpiled backfill or excavation spoils, should not be located within 5 ft or a horizontal distance equal to the depth of the trench, whichever is greater, from the top of the slopes, unless the excavation is properly shored to resist such loads. The stability of temporary rock slopes will be governed by both rock strength parameters and the geometry of the excavation. Our testing of rock core samples include four unconfined compression tests and one saw-cut direct shear test. The results of these tests are presented in Appendix II and are summarized in Table 5. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-15 Report of Geotechnical Engineering Services – Revised Draft March 2011 Table 4 OSHA Classification and Soil Parameters for Temporary Excavations Soil Type OSHA Soil Type Moisture Content (percent) Dry Unit Weight (pcf) Internal Friction Angle (degrees) Cohesion (psf) Structural Fine Grained Fill B (C when water is present) 20 98 30 0 Structural Coarse Grained Fill C 10 115 38 0 Undisturbed Native Silt B (C when water is present) 30 92 33 0 Undisturbed Glacial Outwash C 8 115 36 0 Undisturbed Glacial Till C 9 120 39 0 Table 5 Summary of Rock Core Test Results Boring Depth (feet) Unconfined Compressive strength (psi) Young’s Modulus (psi) Saw Cut Shear Strength (degrees) c (psf) B-1-2010 17 8,384 14,117,000 - - B-2-2010 18.5 13,807 11,278,000 - - B-4-2010 12 987 1,746,000 - - B-5-2010 29 6,992 12,269,000 - - B-1-2010 21 - - 36.1 380 It is important to note that the soil, rock and groundwater conditions may vary significantly across the site. Our soil classifications are based solely on the materials encountered at the specific boring and test pit locations at the time of the explorations. The Contractor should verify that similar conditions exist throughout the proposed area of excavation. If different conditions are encountered at the time of construction, we recommend that shoring methods be modified to suit the conditions encountered at the time of the excavation. It is recommended that any required temporary shoring be designed by a Professional Engineer licensed in the State of Alaska working on the Contractors behalf. We recommend that all appropriate OSHA and AKOSH requirements be incorporated into the design of temporary shoring systems. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-16 Report of Geotechnical Engineering Services – Revised Draft March 2011 4.4.3 Dewatering Construction of the proposed diversion dam will require the temporary diversion of Stetson Creek around the construction area. In addition, excavations for the other proposed site developments will extend below the existing static groundwater level. The Contractor will be responsible for maintaining a dry, undisturbed subgrade. To avoid disturbance to the subgrade, a groundwater should be maintained below the subgrade elevation during the entire period of excavation and fill placement. Dewatering may consist of sumps, wells, wellpoints, cofferdams, sheet pile walls or other means and methods developed by the Contractor, and approved by the Engineer, that is capable of lowering the groundwater below the lowest level of the excavation as required. Design of construction dewatering and stream diversion systems will depend on a number of factors including rate of construction, use of shoring, and type of dewatering system. It is recommended that the dewatering system design be the Contractor’s responsibility, as they will have control of construction means and methods. This will allow the Contractor to provide a dewatering system that is compatible with construction and shoring methods. 4.4.4 Drainage 4.4.4.1 General We recommend foundation drains be placed around the foundations of the diversion pipeline and siphon outlet structures to reduce the effects of pore pressures resulting from varying water levels. The foundation drain should be installed at least 2 ft below the finished floor grade, constructed at a minimum slope of ½ percent, and routed to a suitable discharge. The drains should consist of a perforated drain pipe surrounded by a minimum of 2-ft wide zone of uniformly graded, rock aggregate containing not more than 3 percent fines (material by weight passing the U.S. Standard No. 200 sieve). The aggregate drain rock should be wrapped in a non- woven geotextile filter fabric with an AOS between the U.S. Standard No. 70 and No. 100 sieves. The Contractor should take care to avoid disturbance of the exposed subgrade soils by scheduling excavations to limit the duration of open cuts, sloping the bottoms of the excavations to facilitate drainage, and provide berms to limit runoff into the excavation. In addition, excavated material to be reused as fill should be stockpiled in such a manner that promotes runoff and limits saturation of the materials. 4.4.4.2 Trench Drains The proposed diversion pipeline and construction access road will cross a number of areas that exhibit signs of slope instability. Based the observed site conditions, it is believed that many of these slopes likely experience small movements resulting from high groundwater levels that generally occur on an annual or longer period on average. Where transecting these features is unavoidable, we recommend installing trench drains to help minimize groundwater elevations. Specific locations where trench drains are recommended are presented on Figure 7; however, Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-17 Report of Geotechnical Engineering Services – Revised Draft March 2011 additional drains should be installed as necessary as determined by the Engineer during construction. Trench drains should be at least 18 inches wide and should extend to a depth of 10 ft unless impeded by intact rock. Trench should not extend to elevations below five feet above any adjacent stream or water body. A six-inch diameter perforated pipe drain should be placed near the base of the excavation on at least six inches of free draining pipe bedding material have less than three percent fines. Both the base of the trench and the pipe should be constructed at an out of slope grade of at least three percent. The perforated pipe drain should be routed to a suitable discharge point. The trench and pipe drain should be backfilled to two feet of the original ground surface using free draining, granular backfill containing less than three percent fines. This free draining granular backfill should be wrapped in a non-woven geotextile filter fabric with an AOS between the U.S. Standard No. 70 and No. 100 sieves. The uppermost two feet of backfill should consist of soil having at least 15 percent fines to prevent run-off from overwhelming the drain. A schematic showing typical trench drain cross-sections is presented on Figure 16. 4.4.4.3 Horizontal Drains Horizontal drains should be installed at locations where seepage is encountered in soil cut slopes steeper than 3H:1V and in all permanent rock excavations steeper than 1.5H:1V. In general, horizontal drains should consist of 30-ft deep, 3-inch diameter, PVC cased drains. The drains should be installed with an out of slope dip of 10 degrees and should be spaced on 15-ft centers. The PVC casing should consist of schedule 80 pipe perforated with 0.02-inch slots. Drains should be modified to suit field conditions when determined necessary by the Engineer. 4.4.5 Backfill Materials 4.4.5.1 Structural Fill The on-site gravel, sand, and sandy silt is suitable for use as structural fill provided it can be properly moisture-conditioned and is free of debris and organic material. Structural fill, excluding free draining base rock pads, placed below the diversion outlet, siphon intake, siphon butterfly valve, and siphon outlet should be restricted to on-site gravel and sand containing less than 20 percent fines (silt or clay sized particles), or imported crushed rock aggregate. Soils containing more than about five percent fines (silt or clay sized particles) are sensitive to small changes in moisture content and may be difficult, if not impossible, to compact during wet weather or when the moisture content is more than a few percentage points above the optimum moisture content. We recommend using imported or granular material containing less than five percent fines for structural fill if the on-site material cannot be properly moisture conditioned. During dry weather, structural fill material may consist of virtually any relatively well-graded soil that is free of debris, highly plastic fines, and organic matter that can be compacted to the specified density. Typical structural fill material includes sand, gravel, washed rock, crushed rock, quarry spalls, well-graded mixtures of sand and gravel (commonly called "gravel borrow" or "pit-run"), and miscellaneous mixtures of silt, sand, and gravel. Fill material placed during Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-18 Report of Geotechnical Engineering Services – Revised Draft March 2011 wet weather generally should consist of granular material with a fines content of less than five percent by weight. The maximum particle size should be restricted to 6 inches. All structural fill containing cobble sized particle should be matrix supported. In other words, cobble sized particles should be fully supported by well graded mixture of gravel, sand and fine grained soil. The matrix of structural fill containing cobble sized particles should be compacted as recommended below. Fill containing clast supported cobbles (cobbles that are directly contact and capable of imposing loads on one-another) should be removed from structural areas. Material containing a significant amount of fines, such as silt, clay, or combinations of silt, clay, sand, gravel, and/or cobbles, should be placed in lifts with a maximum uncompacted thickness of 8 inches, and granular fill should be placed in lifts with a maximum uncompacted thickness of 12 inches. Fill material should be brought to within three percent of the optimum moisture content and compacted to not less than 92 percent of the maximum dry unit weight density as determined by ASTM D1557. Regardless of material or location, all structural fill should be placed over firm, unyielding subgrade prepared in accordance with the "Site Preparation" section of this report. A qualified geotechnical engineer should verify the condition of all subgrade before filling begins. Fill soil compaction should be verified by in-place density tests performed during fill placement so that adequacy of soil compaction efforts may be evaluated as earthwork progresses. 4.4.5.2 Pipe Bedding Pipe bedding material should consist of sand, gravel, crushed aggregate, or native free draining granular material conforming to section 703-2.10 “Porous Backfill Material” of the Alaska Department of Transportation and Public Facilities (AKDOT&PF) Standard Specifications for Highway Construction (AKDOT&FG, 2004). It is anticipated that the onsite sand and gravel located in the proposed borrow areas would be suitable for this purpose with some processing. Backfill of the pipe embedment zone, including the bedding zone and pipe zone, should be placed and compacted in maximum lifts of six inches. 4.4.5.3 Trench Backfill Granular trench backfill for the siphon outlet within the existing spillway and in trench drain applications should consist of shot rock, imported crushed rock, or processed onsite gravel. These materials should be well-graded, granular, have less than 3 percent fines (clay and silt sized soil), and have a maximum particle size of 6 inches. Other trench backfill applications should consist of well-graded granular material with a maximum particle size of 1.5-inch and less than 5 percent by weight passing the U.S. Standard No. 200 Sieve. All trench backfill materials should be free of roots, organic matter, and other unsuitable materials. Within the spillway portion of the siphon outlet, trench backfill should be compacted in accordance with the “Structural Fill” section of this report. In other trench backfill applications, backfill above the pipe zone should be placed and compacted with a minimum of two lifts. A Stetson Creek Diversion and Cooper Lake Dam Facilities Page 4-19 Report of Geotechnical Engineering Services – Revised Draft March 2011 minimum cover of 3 ft over the top of the pipe should be placed before compacting with a vibratory plate, or other approved compactor. Within structural areas, trench backfill within 4 ft of the invert elevation of the pipe should be compacted to 92 percent of the maximum dry density as determined by ASTM D1557. Backfill located within structural areas and in excess of 4 ft above the invert elevation of the pipe should be compacted to at least 92 percent of the maximum dry density, as determined by ASTM D1557. In all other areas, trench backfill should be compacted to at least 90 percent of ASTM D1557, unless recommended otherwise by the pipe manufacturer. 4.4.6 Protection and Preparation of Subgrades Care should be taken to minimize traffic on the excavated subgrade prior to placement of the structural fill or concrete foundations. Subgrades should be proof rolled to verify that subgrades are suitable prior to placement of structural fill or concrete foundations. Any unstable or unsuitable material present should be removed and replaced with compacted structural fill or aggregate base. We recommend that the exposed subgrade be scarified to a minimum depth of 6 inches and be compacted to at least 92 percent relative compaction as determined by ASTM D1557. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 5-1 Report of Geotechnical Engineering Services – Revised Draft March 2011 5.0 RECOMMENDATIONS FOR CONSTRUCTION OBSERVATION Satisfactory performance of the proposed Project improvements depends to a large degree on the quality of construction. Sufficient monitoring of the Contractor’s activities is a key part of determining that the work is completed in accordance with construction drawings and specifications. We recommend that a qualified geotechnical engineer be retained to observe excavation, cut slopes, rock bolt installation, compaction and fill placement, subgrade preparation, foundation preparation, and to conduct foundation mapping. Subsurface conditions observed during construction should be compared with those encountered during the subsurface explorations. Recognition of changed conditions often requires experience; therefore, qualified personnel should be present during construction to detect whether subsurface conditions change significantly from those anticipated. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-1 Report of Geotechnical Engineering Services – Revised Draft March 2011 6.0 REFERENCES Alaska Department of Transportation and Public Facilities (AKDOT&PF), 2004. Standard Specifications for Highway Construction. Caterpillar, 2009.Caterpillar Performance Handbook No. 39. Caterpillar, Inc., Peoria, Illinois. Ellsworth, C.E., and Davenport, R.W, 1915. Waterpower Reconnaissance in South Central Alaska. USGS Water Supply Paper 372. Fell, R., MacGregor, P., Stapledon, D. and Bell, G. (Fell, et al.), 2007. Geotechnical Engineering of Dams. A. A. Balkema Publishers, New York, NY. Federal Energy Regulatory Commission (FERC), 2006. Environmental Assessment, Cooper Lake Hydroelectric Project, Alaska (Project No. 2170-029). FERC, 2007. Letter to Chugach Electric Association: Order on Offer of Settlement and Issuing New License, Project No. 2170-029. GEO-SLOPE International, Ltd. (GSI), 2008. Stability Modeling with SLOPE/W 2007 Version, An Engineering Methodology. GEO-SLOPE International, Ltd. Calgary, Alberta. HDR Alaska, Inc. (HDR), 1998. Cooper Lake Hydroelectric Project, Part 12 Safety Inspection Report (Seventh Five-Year Review), FERC Project 2170. September. HDR, 2001. Cooper lake Hydro Project Supplement to 1988 Part 12 Safety Inspection Report. May 18. HDR, 2005. Proposed Stetson Creek Diversion, 2005 Studies Technical Memoranda, Cooper Lake Project (FERC No. 2170). August. HDR and Northern Ecological Services (HDR and NES), 2004. Draft Interim Report: Cooper creek Instream Flow Study and Preliminary Evaluation of Potential Aquatic Habitat Benefits, Cooper Lake Project (FERC No. 2170). August. Inter-Fluve, Inc., 2004.Final Report, Cooper Creek Sediment and Geomorphology Investigation, Cooper Lake Project (FERC No. 2170). June. International Engineering Company, Inc. (IEC), 1983. Cooper Lake Hydroelectric Project, FERC No. 2170, Kenai Peninsula, Alaska, Periodic Safety Inspection Report. August 5. Jones, Fred O. 1965. Inspection of Cooper Lake Hydroelectric Project, Kenai Peninsula, Alaska. August 1. LaCroix and Horn, 1973. Direct Determination and Indirect Evaluation of Relative Density and Its Use on Earthwork Construction Projects: in Evaluation of Relative Density and Its Role in Geotechnical Projects Involving Cohesionless Soils. ASTM Special Technical Publication 523, p. 251-280. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-2 Report of Geotechnical Engineering Services – Revised Draft March 2011 MWH, 2003. Cooper Lake Hydroelectric Project Part 12 Safety Inspection Report, Eighth Five- Year Review, FECR Project No. 2170, October. MWH, 2004. Cooper Lake Project, FERC No. 2170, Potential Cooper Creek Protection, Mitigation, and Enhancement Measures, DRAFT. August. MWH, 2008. Cooper Lake Hydroelectric Project Part 12 Safety Inspection Report, Ninth Five- Year Review, FERC Project No. 2170. August. MWH, 2010a. Stetson Creek Diversion and Cooper Lake Dam Facilities Geotechnical Feasibility Report. January. MWH, 2010b. Stetson Creek Diversion and Cooper Lake Dam Facilities Feasibility Report. February. Nelson, Steven W., Dumoulin, J.A., and Miller, Marti L., 1985. Geologic Map of the Chugach National Forest, Alaska. USGS MF-1645-B. North Pacific Consultants (NPC), 1955. Definite Project Report on Cooper Lake Hydroelectric Project, Kenai Peninsula, Alaska. December 29. NPC, 1958. Geology of the Cooper Lake Tunnel Site cooper Lake Hydroelectric Project, Kenai Peninsula, Alaska, Information for Bidders. August 28. NPC, 1958b. Cooper Lake Project Alaska 8 “H” Chugach, Project Roads, Report on Construction Materials. September 2. NPC, 1959. Cooper Lake Project, F.P.C. License No. 2170, R.E.A. Project: Alaska 8H Chugach, Design Report, Cooper Lake Dam. March. Plafker, George, 1955. Geologic Investigations of Proposed Power Sites at Cooper, Grant, Ptarmigan and Crescent Lakes Alaska. Geology of Power Sites in Alaska, USGS Bulletin 1031-A. Stone & Webster, 1987. Cooper Lake Dam, Technical Specification for Spillway Enlargement and Parapet Wall Installation, Issued for Bid. May 23. Stone & Webster, 1988. Fifth Periodic Safety Inspection Report, Cooper Lake Hydroelectric Project, FERC Project No. 2170, Kenai Peninsula, Alaska. September 1. Stone & Webster, 1997. Cooper Lake Dam, Technical Specification for Spillway Enlargement and Parapet Wall Installation, Issued For Bid. May. U.S. Army Corps of Engineers (USACE), 1983. Engineering and Design, Rock Mass Classification Data Requirements for Rippability. Engineering Technical letter No. 1110- 2-282. June 30. Stetson Creek Diversion and Cooper Lake Dam Facilities Page 6-3 Report of Geotechnical Engineering Services – Revised Draft March 2011 U.S. Bureau of Reclamation (USBR), 1998. Engineering Geology Field Manual. Second Edition, volume 1. U.S. Department of Agriculture – Natural Resources Conservation Service (USDA-NRCS), 1994.National Engineering Handbook. Part 633, Chapter 26. U.S. Geologic Survey – National Earthquake Information Center (USGS-NEIC), 2010a. Recorded Earthquake Database (1973 to 2010). Queried December 27, 2010. USGS-NEIC, 2010b. Significant U.S. Earthquakes Database (1568-1989). Queried December 27, 2010. U.S. Society on Dams (USSD), 2007. Strength of Materials for Embankment dams. USSD Committee on Materials for Embankment Dams. Weaver, Kenneth D. and Bruce, Donald A., 2007. Dam Foundation Grouting: Revised and Expanded Edition. American Society of Civil Engineers, Reston, VA. Wilson, Frederic H. and Chad P. Hults (Compilers), 2007. (Draft) Geology of the Prince William Sound and Kenai Peninsula Region, Alaska. USGS. FIGURES APPENDIX I 2010 Boring Procedures, Logs, and Photographs . Stetson Creek Diversion and Cooper Lake Dam Facilities Report of Geotechnical Engineering Services – Revised Draft March 2011 APPENDIX I 2010 BORING PROCEDURES, LOGS, AND PHOTOGRAPHS The design level geotechnical exploration program included six (6) subsurface boring explorations (B-1-2010 through B-6-2010). Borings B-1-2010 and B-2-2010 were conducted using a platform-mounted CME 45 drill rig using NQ triple tube rock coring methods to depths of 40.4 and 30.0 ft, respectively. Borings B-3-2010 through B-6-2010 were conducted using a track-mounted CME 850 drill rig. Boring B-3-2010 was conducted using both mud-rotary and HQ triple tube rock coring methods to a depth of 47.7 ft. Borings B-4-2010 and B-5-2010 were conducted using HQ triple tube rock coring methods to a depth of 30.0 feet in each hole. Boring B-6-2010 was conducted using mud-rotary drilling methods to a depth of 51.5 ft. The subsurface boring explorations were conducted by Discovery Drilling of Anchorage, Alaska between July 6, 2010 and July 13, 2010. Borings B-3-2010 and B-6-2010 were backfilled with hydrated bentonite chips. The remaining borings were backfilled with cement-bentonite grout. The location of each boring was surveyed by McClane Consulting, Inc. of Soldotna, Alaska. Boring locations are shown on Figures 3 and 6. Down-hole televiewer surveying was conducted on borings B-2-2010 and B-5-2010 by Northwest Geophysical Associates, Inc. of Corvallis, Oregon. Televiewer surveys of the remaining rock core borings were not completed due to caving conditions at the time of the surveys. Down-hole televiewer survey logs are presented in Appendix III. Soils encountered were classified in accordance with the ASTM International (ASTM) D 2488, Practice for Description and Identification of Soils (Visual-Manual Procedure). Soil samples were collected from disturbed, California Modified split-spoon samplers driven with a 300-lb hammer at regular intervals. Collected samples were packaged and shipped to laboratories for testing in general accordance with the procedures outlined by ASTM D 4220, Standard Practices for Preserving and Transporting Soil Samples. Rock conditions encountered were classified in accordance with the United States Bureau of Reclamation’s (USBR’s) Engineering Geology Field Manual (1998). Continuous rock core samples were collected and classified from each of the rock core borings. Rock drilling, sample storage, and sample transport were conducted in general accordance with ASTM D 2113, Standard Practice for Diamond Core Drilling for Site Investigation. Exploration logs and photographs of borings B-1-2010 through B-6-2010 are presented in the following pages. 1 2 3 4 5 6 7 8 9 10 11 12 13 1 2 3 4 5 6 7 8 9 10 11 12 13 Depth: Distance in feet below the collar of the boring. Graphic Log: A depiction of material encountered in boring using symbols to represent individual groups of rock and soil stratigraphy. Material Description: Lithologic description of the rock and soil encountered. Sample Type/Number: Type and identification number of sample collected at depth interval shown. Recovery/RQD: Actual soil recovery in sampler as a percentage of the sampler penetration. Refer to Key to Rock Core Logs for description of RQD. Blow Counts: Number of blows to advance a Modified California sampler each six-inch drive interval, or distance noted, using a 300-lb auto-trip hammer with a 30-inch drop. Pocket Pen.: Index test results for a pocket penetrometer expressed in tons per square foot. Dry Unit Weight: Unit weight of soil determined by ASTM D4767. Expressed in pounds per cubic foot. Moisture Content: Laboratory moisture content expressed as a percentage determined by ASTM D2216. Liquid Limit: Laboratory liquid limit of soil determined by ASTM D5731. Expressed as a percentage. Plastic Limit: Laboratory plastic limit of soil determined by ASTM D5731. Expressed as a percentage. Plastic Index: Plastic index of soil (Liquid Limit - Plastic Limit) determined by ASTM D5731. Expressed as a percentage. Fines Content: Amount of soil passing a Standard US No. 200 Sieve as determined by ASTM D422 and D1140. GEOLOGICAL TESTING COLUMN DESCRIPTIONS TYPICAL ROCK GRAPHIC SYMBOLS Run No.: Number of the individual coring interval. Depth of top and Slate bottom of coring interval in parentheses. Claystone/Mudstone Bit: Core or drill bit used during coring interval. Siltstone Recovery: Amount (in percent) of core recovered from the coring interval; calculated as length of core recovered divided by length of run. Sandstone RQD: (Rock Quality Designation) Amount (in percent) of intact core (pieces of sound core greater than 4 inches long) in each coring ABBREVIATIONS interval; calculated as the sum of lengths of intact core divided by length of core run. Ck Creek E Easting Depth: Distance (in feet) below the collar of the borehole.FD_Fracture Density Descriptor ft Feet Geology: Graphic log of material encountered in boring using H_Hardness/Strength Descriptor symbols to represent individual groups rock stratigraphy.HL_Fracture Healing Descriptor in Inch Degree of Weathering: Condition of rock mass with respect to J Joint decomposition in accordance with the USBR classification system. Lk Lake Refer to Key to Rock Descriptions for additional details.MB Mechanical Break N Northing Discontinuities Per Foot: (Fracture Index or Fracture Frequency) NQTT NQ Triple Tube The number of naturally occurring discontinuities per foot of core.O_Fracture Openness Descriptor R_Joint Roughness Descriptor Discontinuity Type: Indicates type of imperfection in the rock core. S Shear May include joints, faults, shears, bedding, mechanical breaks etc.SP_Joint Spacing Descriptor T_Fracture Filling Thickness Descriptor Discontinuity Dip: Angle formed between the discontinuity and a W_Weathering Descriptor (ft) Geology Degree of Weathering Discontinuities Description Discont./ft. Type Dip KEY TO ROCK CORE LOGS DRILLING/GEOMECHANICAL Run No. (Start - Stop)BitRecovery (%)RQD (%)Depth 0 2 4 6 8 60 20 80 40 60 20 80 40 W1 W5 W9 W3 W7 1 2 3 4 5 6 7 8 9 10 12 13 1 2 3 4 5 6 7 8 9 10 11 Testing Notes: Drilling Rate Blocking Water loss plane orthogonal to the boring axis. Discontinuity Column: Provides a graphical depiction of the discontinuities observed in the core. Geologic Description: Detailed description of the rock conditions encountered in the core. Descriptions are in accordance with USBR field manual. Refer to Key to Rock Descriptions for additional detail. Testing: Indicates depths that field or laboratory tests were conducted. Also provides notes on related field observations and drilling data. PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 1 of 9 0 2 4 6 8 60 20 80 40 60 20 80 40 W1 W5 W9 W3 W7 1 2 3 4 5 6 7 8 9 10 12 13 1 2 3 4 5 6 7 8 9 10 11 11 12 13 Testing Notes: Drilling Rate Blocking Water loss GRAIN SIZE DESCRIPTORS BEDDING, FOLIATION, OR FLOW TEXTURE DESCRIPTORS Descriptor Grain Size Descriptor Thickness Very Coarse Grained or Pegmatitic >3/8 in Massive >10 ft Coarse Grained 3/16 to 3/8 in Very Thickly, Bedded, Foliated, or Banded 3 to 10 ft Medium Grained 1/32 to 3/16 in Thickly 1 to 3 ft Fine Grained 0.04 to 1/32 in Moderately 0.3 to 1 ft Aphanitic <0.04 in Thinly 0.1 to 0.3 ft Very Thinly 3/8 in to 0.1 ft Laminated (Intensely Foliated or Banded) <3/8 in WEATHERING DESCRIPTORS Numeric Descriptor Description Fresh No discoloration or oxidation. No change to texture or solutioning. Slightly Weathered to Fresh Slightly Weathered Discoloration or oxidation is limited to surface or short distance from fractures. Some feldspars are dull. Texture is preserved. Minor leaching of some soluble minerals. Moderately to Slightly Weathered Moderately Weathered Discoloration or oxidation extends from fractures, usually throughout. Feldspars are cloudy. Texture is generally preserved. Soluble minerals may be mostly leached. Intensely to Moderately Weathered Intensely Weathered Discoloration or oxidation throughout. All feldspars and Fe-Mg minerals are altered to clay to some extent. All fractured surfaces are discolored or oxidized. Texture is altered by chemical disintegration. Leaching of soluble minerals may be complete. Very Intensely Weathered Decomposed Discolored or oxidized throughout. Resembles soil. Partial or complete remnant rock structure may be preserved. Leaching of soluble minerals usually complete. ROCK HARDNESS/STRENGTH DESCRIPTORS Numeric Descriptor Description E t l H d C t b t h d ith k if b hi d ith t d h h blH1 W4 W5 W6 W7 W8 W9 KEY TO ROCK CORE LOGS ROCK DESCRIPTORS W1 W2 W3 Extremely Hard Cannot be scratched with knife; can be chipped with repeated heavy hammer blows. Very Hard Cannot be scratched with knife; Core or fragment breaks with repeated heavy hammer blows. Hard Can be scratched with knife or sharp pick with difficulty; Heavy hammer blow required to break specimen. Moderately Hard Can be scratched with knife or sharp pick with light or moderate pressure. Core or fragment breaks with moderate hammer blow. Moderately Soft Can be grooved 1/16 in deep by knife or sharp pick with moderate or heavy pressure. Core or fragment breaks with light hammer blow or heavy manual pressure. Soft Can be grooved or gouged easily by knife or sharp pick with light pressure, can be scratched with fingernail. Breaks with light to moderate manual pressure. Very Soft Can be readily indented, grooved or gouged with fingernail, or carved with knife. Breaks with light manual pressure. H1 H7 H5 H6 H2 H3 H4 PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 2 of 9 FRACTURE DENSITY DESCRIPTORS Numeric Descriptor Description Unfractured No observed fractures. Very Slightly Fractured Core recovered mostly in lengths greater than 3 ft. Slightly to Very Slightly Fractured Slightly Fractured Core recovered mostly in lengths from 1 to 3 ft with few exceptions. Moderately to Slightly Fractured Moderately Fractured Core recovered mostly in lengths from 0.33 to 1 ft with most lengths about 0.67 ft. Intensely to Moderately Fractured Intensely Fractured Lengths average from 0.1 to 0.33 ft with fragmented intervals. Core recovered mostly in lengths less than 0.33 ft. Very Intensely to Intensely Fractured Very Intensely to Intensely Fractured Core recovered mostly as chips and fragments with a few scattered short core lengths. JOINT SPACING DESCRIPTORS Numeric Descriptor Description Extremely Widely Spaced >10 ft Very Widely Spaced 3 to 10 ft Widely Spaced 1 to 3 ft Moderately Widely Spaced 0.3 to 1 ft Closely Spaced 0.1 to 0.3 ft Very Closely Spaced <0.1 ft FRACTURE OPENNESS DESCRIPTORS Numeric Descriptor Description Tight No visible separation. Slightly Open < 1/32 in Moderately Open 1/32 to 1/8 in Open 1/8 to 3/8 in M d t l Wid 3/8 i t 0 1 ft SP5 O1 O2 O3 O4 SP6 O0 FD8 SP1 SP2 SP3 FD9 SP4 FD0 FD1 FD2 FD4 FD5 FD7 FD3 FD6 KEY TO ROCK CORE LOGS ROCK DISCONTINUITY DESCRIPTORS Moderately Wide 3/8 in to 0.1 ft Wide >0.1 ft FRACTURE FILLING THICKNESS DESCRIPTORS Numeric Descriptor Description T0 Clean No film coating. T1 Very Thin <1/32 in T2 Moderately Thin 1/32 to 1/8 in T3 Thin 1/8 to 3/8 in T4 Moderately Thick 3/8 in to 0.1 ft T5 Moderately Thick >0.1 ft O4 O5 PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 3 of 9 FRACTURE HEALING DESCRIPTORS Numeric Descriptor Description Totally Healed Completely healed or recemented to a degree at least as hard as surrounding rock. Moderately Healed Greater than 50 percent of the fracture material, fracture surfaces, or healed filling is healed or recemented; and/or strength of the healing agent is less hard than surrounding rock. Partially Healed Less than 50 percent of fractured material, filling, or fracture surface is healed or recemented. Not Healed Fracture surface, fracture zone, or filling is not healed or recemented; rock fragments or filling (if present) is held in place by its own angularity and/or cohesiveness. FRACTURE ROUGHNESS DESCRIPTORS Numeric Descriptor Description Stepped Near normal steps and ridges occur on the fracture surface. Rough Large, angular asperities can be seen. Moderately Rough Asperities are clearly visible and fractured surface feels abrasive. Slightly Rough Small asperities on the fracture surface are visible and can be felt. Smooth No asperities, smooth to the touch. Polished Extremely smooth and shiny. R3 R4 R5 R6 R1 R2 HL0 HL2 HL3 HL5 KEY TO ROCK CORE LOGS ROCK DISCONTINUITY DESCRIPTORS (CONTINUED) PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 4 of 9 Stetson Ck./Cooper Lk ELEVATION 1453.5 ft DRILLING CONTRACTOR: Discovery Drilling, Inc. Diversion Lt. Abutment INCLINATION Vertical RIG: CME 45 - Platform Mounted N 2349989 DIRECTION N/A START: July 7, 2010 E 525565.2 LOGGED BY P. Richards FINISH: July 8, 2010 GEOLOGICAL TESTING SLATE: Dark gray, fine grained, slightly weathered to fresh (W2), moderately hard (H4), very intensely 26 0 fractured (FD9); Discontinuities are very closely spaced (SP6), tight to slightly open (O0 to O1), clean to thinly J 25 filled (T0 to T1), partly healed (HL3), slightly rough (R4), 50 0 and predominately dip at 25-30 degrees. (Potentially Water loss at 5 to displaced rock)7 ft 27 0 Blocked off at 7.5 ft 60 0 60 0 J 20,50 J 25, 30, 90 SLATE: Dark gray, fine grained, slightly weathered to J/MB 80/0 fresh (W2), moderately hard (H4), intensely to MB 0 moderately fractured (FD6); Discontinuities are Packer Test 15 to J/MB 20/20 moderately to closely spaced (SP3 to SP4), tight to 40.4 ft = 100 58 S 20 moderately open (O0 to O2), clean to very thinly filled (T0 0.5 Lugeons to T1), partly healed (HL3), slightly rough (R4), predominately dip at 30, 50 to 60, and 75 degrees, and J/MB 20/10 are occasionally slickensided. MB 20 100 56 S 30 Moderately rough (R3) at 22.2 ft. J 15 J 70 MB 60 J/MB 40/20 100 100 S 55 MB 60 J/MB 40/70,80 J/MB 20/0 98 86 S 10 MB 0, 20 PROJECT Discont./ft. DRAFT LOG OF COREHOLE NO. B-1 DRILLING/GEOMECHANICAL Description COORDINATES (ft) Depth LOCATION Run No. (Start - Stop)BitRecovery (%)RQD (%)1 (0.0 - 5.0)25 (10.0 - 15.0)DipGeology DiscontinuitiesDegree of Weathering Type 0 2 4 6 8 5 10 15 20 25 30 35 60 20 80 40 60 20 80 40 34NQTT6 (15.0 - 20.2)7 (20.2 - 25.2)9 (30.4 - 35.4) 8 (25.2 - 30.4) W1 W5 W9 W3 W7 Testing Notes: Drilling Rate Blocking Water loss S 30 S/J 85/10,80 100 52 S/J 10,65/30 S/J 5/15 J/MB 85/10, 30 Terminal Depth = 40.4 ft Packer Test Conducted from 15 to 40.4 ft Notes Run 2 from 5.0 to 7.0 ft Run 3 from 7.0 to 8.5 ft Run 4 from 8.5 to 10.0 ft THIS SUMMARY APPLIES ONLY AT THE LOCATION OF THIS BORING AT THE TIME OF DRILLING. SUBSURFACE CONDITIONS MAY DIFFER AT OTHER LOCATIONS AND MAY CHANGE AT THIS LOCATION WITH THE PASSAGE OF TIME. THE DATA PRESENTED IS A SIMPLIFICATION OF ACTUAL CONDITIONS ENCOUNTERED. PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 5 of 9 0 2 4 6 8 5 10 15 20 25 30 35 40 45 60 20 80 40 60 20 80 40 55 5034NQTT6 (15.0 - 20.2)7 (20.2 - 25.2)9 (30.4 - 35.4) 8 (25.2 - 30.4)10 (35.4 - 40.4) W1 W5 W9 W3 W7 Testing Notes: Drilling Rate Blocking Water loss Stetson Ck./Cooper Lk ELEVATION 1437.8 ft DRILLING CONTRACTOR: Discovery Drilling, Inc. Diversion Rt. Abutment INCLINATION Vertical RIG: CME 45 - Platform Mounted N 2349922 DIRECTION N/A START: July 6, 2010 E 525566.7 LOGGED BY P. Richards FINISH: July 7, 2010 GEOLOGICAL TESTING J 60 SLATE: Dark gray, fine grained, slightly weathered to J 50, 90 fresh (W2), moderately hard (H4), intensely to 92 24 moderately fractured (FD6); Discontinuities are J 0,10 moderately to closely spaced (SP3 to SP4), tight to J 50 moderately open (O0 to O2), clean to very thinly filled J 5, 10, 80 (T0 to T1), partly healed (HL3), slightly rough (R4), J 5 predominately dip at 30, 50 to 60, and 75 degrees, 98 60 J 40 and are occasionally slickensided. J/MB 75/10 J 10, 45 J/MB 10/5 Packer test 10.0 J 0 to 30.0 ft = 100 88 J/MB 30/10 0.0 Lugeons J 20 J 30,75 J 10 100 76 J/MB 35/30 J/MB 35, 70/30 Blocked off at 90 86 MB 30 17.9 ft. J/MB 50,70/45 S 70 -Clay infilling at 20.8 ft. J/MB 65/30 92 38 J 10, 50, 60 J 10, 50, 60 Very intensely fractured (FD9) between 22.5 and 23.2 ft. 100 50 J 30 Blocked off at 25.8 ft. 100 88 J 30,50 Terminal Depth = 30.0 ft Packer Test Conducted from 10.0 to 30.0 ft DRAFT LOG OF COREHOLE NO. B-2 PROJECT LOCATION COORDINATES Run No. (Start - Stop)BitRecovery (%)RQD (%)Depth Degree of Weathering Description Discont./ft. Type DipGeology Discontinuities (ft)1 (0.0 - 5.0)0 2 4 6 8 5 10 15 20 25 30 35 60 20 80 40 60 20 80 40 2 (5.0 - 10.0)NQTT4 (15.0 - 17.9)6 (20.0 - 25.0)73 (10.0 - 15.0)58 (25.8 - 30.0) W1 W5 W9 W3 W7 Testing Notes: Drilling Rate Blocking Water loss Notes: Run 5 from 17.9 to 20.0 ft Run 7 from 25.0 to 25.8 ft THIS SUMMARY APPLIES ONLY AT THE LOCATION OF THIS BORING AT THE TIME OF DRILLING. SUBSURFACE CONDITIONS MAY DIFFER AT OTHER LOCATIONS AND MAY CHANGE AT THIS LOCATION WITH THE PASSAGE OF TIME. THE DATA PRESENTED IS A SIMPLIFICATION OF ACTUAL CONDITIONS ENCOUNTERED. PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 6 of 9 0 2 4 6 8 5 10 15 20 25 30 35 40 45 60 20 80 40 60 20 80 40 55 502 (5.0 - 10.0)NQTT4 (15.0 - 17.9)6 (20.0 - 25.0)73 (10.0 - 15.0)58 (25.8 - 30.0) W1 W5 W9 W3 W7 Testing Notes: Drilling Rate Blocking Water loss Stetson Ck./Cooper Lk ELEVATION 1189.7 ft DRILLING CONTRACTOR: Discovery Drilling, Inc. Near Siphon Intake INCLINATION Vertical RIG: CME 850 - Track Mounted N 2350220.0 DIRECTION N/A START: July 11, 2010 E 532275.3 LOGGED BY P. Richards FINISH: July 12, 2010 GEOLOGICAL TESTING See Boring Log for Description of B-3 between depths of 0.0 and 28.0 ft. J 50 SLATE: Dark gray, fine grained, slightly weathered to J 50 fresh (W2), moderately hard (H4), intensely to 100 22 J/MB 60,70 moderately fractured (FD6); Discontinuities are J 40,50 moderately to closely spaced (SP3 to SP4), tight to J 50,60,70 moderately open (O0 to O2), clean to very thinly filled J 50,60 (T0 to T1), partly healed (HL3), slightly rough (R4), Geology Degree of Weathering Discontinuities Description BitRecovery (%)RQD (%)Depth Discont./ft. Type Dip DRAFT LOG OF COREHOLE NO. B-3 PROJECT LOCATION COORDINATES (ft)Run No. (Start - Stop)0 2 4 6 8 5 10 15 20 25 30 35 60 20 80 40 60 20 80 40 HQTT7(28.8-30.0)1(28.0 - 32.5)- 37.5) W1 W5 W9 W3 W7 Testing Notes: Drilling Rate Blocking Water loss 86 0 J 40, 50 predominately dip at 30 to 65 degrees, and are J 30,40,50 occasionally slickensided.Lost circulation at J 50 -Very intensely fractured zone 32.5 to 34.5 ft.35 ft. J 50,60 -Very intensely fractured zone 37.0 to 37.5 ft. J/MB 30 -Very intensely fractured zone 38.5-41.2 ft. 100 0 J 40,50 Blocked off at 41.2 95 0 J 50, 60 ft. J 40, 60 J 60 92 0 J 45,60,70 -Very intensely fractured zone 46.0 to 47.0 ft. J 30,50,60 Terminal Depth = 47.7 ft. Boring Backfilled with hydrated bentonite chips. Notes: Run 3 from 37.5 to 38.5 ft Run 5 from 41.2 to 43.2 ft THIS SUMMARY APPLIES ONLY AT THE LOCATION OF THIS BORING AT THE TIME OF DRILLING. SUBSURFACE CONDITIONS MAY DIFFER AT OTHER LOCATIONS AND MAY CHANGE AT THIS LOCATION WITH THE PASSAGE OF TIME. THE DATA PRESENTED IS A SIMPLIFICATION OF ACTUAL CONDITIONS ENCOUNTERED. PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 7 of 9 0 2 4 6 8 5 10 15 20 25 30 35 40 45 60 20 80 40 60 20 80 40 55 50HQTT7(28.8-30.0)1(28.0 - 32.5)2(32.5 - 37.5)3100 30 4 (38.5 - 41.2)56 (43.2 - 47.7) W1 W5 W9 W3 W7 Testing Notes: Drilling Rate Blocking Water loss Stetson Ck./Cooper Lk ELEVATION 1206.1 ft DRILLING CONTRACTOR: Discovery Drilling, Inc. Southeastern Spillway INCLINATION Vertical RIG: CME 850 - Track Mounted N 2350263.9 DIRECTION N/A START: July 10, 2010 E 532063.3 LOGGED BY P. Richards FINISH: July 10, 2010 GEOLOGICAL TESTING J 50 SLATE: Dark gray, fine grained, slightly weathered to J 50,40 fresh (W2), moderately hard (H4), intensely to 92 50 J 40 moderately fractured (FD6); Discontinuities are J/MB 0,20/40 moderately to closely spaced (SP3 to SP4), tight to S/J 35/40,85 moderately open (O0 to O2), clean to very thinly filled J 45 (T0 to T1), partly healed (HL3), slightly rough (R4), J/MB 40,50/30 predominately dip at 30 to 60 75 degrees, and are 100 16 J 30,60 occasionally slickensided. S/J 55/40,45,60 -Very intensely fractured (FD9) zones at 4.1 to 4.2, 4.7 to Blocked off at 9.9 J 40 4.9, 5.4 to 5.6, 9.0 to 9.9, 11.5 to 11.6, 14.5 to 15.7, 22.7 ft. J 50 to 23.1, 23.8 to 25.3, and 28.8 to 30.0 ft. 100 70 J 25,40 J 40,50,60 Blocked off at J 50 14.5 ft. 100 60 J 40,45,50 J 40 Thin iron-oxide stain at 18.0 ft.Blocked off at J 60,70 18.8 ft. S/J/MB 45/20/40 100 42 S 45 -1/8-inch gouge at 21.9 ft. J 45 J 20 100 60 J 30,40 J/MB 20,50/10 J 20,40,60 67 0 J 60 Terminal Depth = 30.0 ft Notes: DRAFT LOG OF COREHOLE NO. B-4 PROJECT LOCATION COORDINATES Run No. (Start - Stop)BitRecovery (%)RQD (%)Depth Degree of Weathering Description Discont./ft. Type DipGeology Discontinuities (ft)1 (0.0 - 5.0)0 2 4 6 8 5 10 15 20 25 30 35 60 20 80 40 60 20 80 40 2 (5.0 - 9.9)HQTT4 (14.5-18.8)6 (23.8 - 28.8)73 (9.9-14.5)5 (18.8-23.8)W1 W5 W9 W3 W7 Testing Notes: Drilling Rate Blocking Water loss Run 7 from 28.8 to 30.0 ft THIS SUMMARY APPLIES ONLY AT THE LOCATION OF THIS BORING AT THE TIME OF DRILLING. SUBSURFACE CONDITIONS MAY DIFFER AT OTHER LOCATIONS AND MAY CHANGE AT THIS LOCATION WITH THE PASSAGE OF TIME. THE DATA PRESENTED IS A SIMPLIFICATION OF ACTUAL CONDITIONS ENCOUNTERED. PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 8 of 9 0 2 4 6 8 5 10 15 20 25 30 35 40 45 60 20 80 40 60 20 80 40 55 502 (5.0 - 9.9)HQTT4 (14.5-18.8)6 (23.8 - 28.8)73 (9.9-14.5)5 (18.8-23.8)W1 W5 W9 W3 W7 Testing Notes: Drilling Rate Blocking Water loss Stetson Ck./Cooper Lk ELEVATION 1205.9 ft DRILLING CONTRACTOR: Discovery Drilling, Inc. Northwestern Spillway INCLINATION Vertical RIG: CME 850 - Track Mounted N 2350508.4 DIRECTION N/A START: July 10, 2010 E 531822.8 LOGGED BY P. Richards FINISH: July 10, 2010 GEOLOGICAL TESTING J 60 SLATE: Dark gray, fine grained, slightly weathered to J/MB 65/60 fresh (W2), moderately hard (H4), intensely to 100 54 J/MB 60/20,0 moderately fractured (FD6); Discontinuities are S 35,65 moderately to closely spaced (SP3 to SP4), tight to 100 55 J/MB 45/30 moderately open (O0 to O2), clean to very thinly filled (T0 to T1), partly healed (HL3), slightly rough (R4), J 35,50 predominately dip at 30 to 65 degrees, and are 100 88 J/MB 50,55/45 occasionally slickensided. J/MB 40,55,80/40 -Very intensely fractured (FD9) from 0.0 to 0.9 feet. J 40 -3/4-inch thick silty clay infilling at 3.8 ft.Blocked off at S/J 50,65/50,70 3.9 ft. 100 58 J 50,70 J/MB 50,65/0 J/MB 50/30 J/MB 20,30,70/0 J 20,30,65,70 -Very intensely fractured (FD9) at 16.0 to 16.1 ft. 90 33 -Very intensely fractured (FD9) at 17.6 to 18.5 ft. J 30 J 20,50 J 60 100 96 MB 40 J/MB 50 100 0 J 50 Blocked off at J 50 25.2 ft. 100 100 MB 10 J 40,50 Terminal Depth = 30.0 ft DRAFT LOG OF COREHOLE NO. B-5 PROJECT LOCATION COORDINATES (ft) Description DiscontinuitiesDegree of Weathering Discont./ft. Type DipGeology Run No. (Start - Stop)BitRecovery (%)RQD (%)Depth 0 2 4 6 8 5 10 15 20 25 30 35 60 20 80 40 60 20 80 40 Testing Notes: Drilling Rate Blocking Water loss 2HQTT5 (14.5-20.0)77(28.8-30.0)3 (5.0 - 10.0)6 (20.0 - 25.0)1(0.0 - 3.9)4 (10.0 - 14.5)8 (25.2 - 30.0) W1 W5 W9 W3 W7 Notes: Run 2 from 3.9 to 5.0 ft Run 7 from 25.0 to 25.2 ft THIS SUMMARY APPLIES ONLY AT THE LOCATION OF THIS BORING AT THE TIME OF DRILLING. SUBSURFACE CONDITIONS MAY DIFFER AT OTHER LOCATIONS AND MAY CHANGE AT THIS LOCATION WITH THE PASSAGE OF TIME. THE DATA PRESENTED IS A SIMPLIFICATION OF ACTUAL CONDITIONS ENCOUNTERED. PROJECT NO. 1007059 CHUGACH ELECTRIC ASSOCIATION STETSON CREEK DIVERSION AND COOPER LAKE OUTLET KENAI BOROUGH, ALASKA PAGE 9 of 9 0 2 4 6 8 5 10 15 20 25 30 35 40 45 60 20 80 40 60 20 80 40 55 50 Testing Notes: Drilling Rate Blocking Water loss 2HQTT5 (14.5-20.0)77(28.8-30.0)3 (5.0 - 10.0)6 (20.0 - 25.0)1(0.0 - 3.9)4 (10.0 - 14.5)8 (25.2 - 30.0) W1 W5 W9 W3 W7 APPENDIX II 2010 Laboratory Testing Program and Results Stetson Creek Diversion and Cooper Lake Dam Facilities Report of Geotechnical Engineering Services – Revised Draft March 2011 APPENDIX II 2010 LABORATORY TESTING PROGRAM Primary geotechnical laboratory testing of soil and aggregate was conducted by Terra Firma Testing, Inc. of Anchorage, Alaska. Additional confirmation testing of selected soil samples was conducted by ACS Testing, Inc. of Tigard, Oregon. Rock core testing was conducted by Cooper Testing Labs, Inc. of Palo Alto, California. All tests were conducted in accordance or in general accordance with applicable ASTM standards. Descriptions of the laboratory tests conducted on selected soil samples are presented below. Test results are summarized in the exploration logs in Appendix I and are detailed in the following pages. California Modified Spilt Spoon Penetration Tests California Modified split spoon penetration tests were conducted in regular intervals within soil substrates in general accordance with methods prescribed by ASTM for Standard Penetration Testing (ASTM D1586). The test involves driving a 3-inch outside diameter split spoon sampler for three intervals of six inches using a 340-lb auto hammer with a drop height of 30 inches. The number of hammer blows required to drive the sample each 6-inch interval is recorded, and the sum of the blow counts over the second and third interval is presented as a raw blow count or “N-value”. This raw value can then be related to standard penetration test N-values using relationships such as that presented by LaCroix and Horn (1973). Water Pressure Testing Water pressure testing was performed in two rock core borings located at the proposed diversion dam. The tests were performed of a selected interval that was isolated from the remainder of the boring using a pneumatic, rubber seal packer. Each of the water pressure tests were comprised of five pressure stages: Stage 1 – 5 psi; Stage 2 – 10 psi; Stage 3 – 15 psi; Stage 4 – 10 psi; and Stage 5 – 5 psi. The water flow for each stage was measured from an analog water meter and recoded manually. The data from each test is presented in Lugeons, a unit of permeability used to evaluate rock groutability and the effectiveness of grouting programs in rock. One Lugeon is defined as 1 liter (0.26 gallons) of water loss per minute, per meter (3.28 feet) of bore hole at a pressure of 1 megapascal (145 psi). Moisture Testing Moisture content tests were performed on a number of samples recovered from the test pits. The results of these tests were used to aid in evaluating soil properties. Moisture content tests were conducted in accordance with ASTM D 2216. Sieve Analysis Sieve analyses (combined sieve with hydrometer analyses and material passing a US Standard No. 200 sieve) were performed on selected samples of the subsurface materials. These tests were performed to evaluate the gradation characteristics of the soils and to aid in their classification. These tests were performed in accordance with ASTM D 422 and ASTM D 1140. Stetson Creek Diversion and Cooper Lake Dam Facilities Report of Geotechnical Engineering Services – Revised Draft March 2011 Atterberg Limits Testing (Liquid Limit, Plastic Limit and Plasticity Index) Atterberg limits are used primarily for classifying and indexing cohesive soil. The liquid and plastic limits, which are defined as the moisture content of a cohesive soil at established limits for liquid and plastic behavior, respectively, were determined for a core material sample from Cooper Lake Dam. Atterberg limits testing was conducted in accordance with the guidelines presented in ASTM D 4318. Plasticity Index (PI) is defined as the difference in water content between the liquid limit (LL) and plastic limit (PL). Soil Classification Visual soil classifications were conducted on all soil samples in the field and confirmed with laboratory testing. All soils were classified in accordance with the Unified Soil Classification System as described by ASTM D 2487 and ASTM D 2488 as appropriate, which includes: stiffness/ relative density, color, major soil type (based on grain size), minor soil types, and relative moisture content. Classifications and sampling intervals are shown in the exploration logs presented in Appendix I of this report. The logs indicate the depths at which the soils or their characteristics change at the location of the exploration, although the changes may actually be gradual. If the change occurred between sample locations, the depth of change was interpreted. Unconfined Rock Strength The unconfined strength and elastic modulus of intact rock core samples was tested on four selected samples. This test was used to determine the compressive strength and deformation properties of intact rock core samples. These tests were conducted in accordance with ASTM D 7012. Direct Shear Strength of Rock Direct shear strength of rock was conducted on a selected saw-cut core sample. This test was conducted to approximate the minimum shear strength of the rock along existing joints within the rock mass. This test was conducted in accordance with ASTM D 5607. Petrographic Examination of Aggregates A petrographic examination of a selected bulk sample was conducted on a sample collected at the ground surface at the location of a proposed borrow area. The petrographic examination was used to determine the chemical and mineral characteristics of the bulk sample to aid in the evaluation of the aggregates suitability for use on the proposed Project. The petrographic examination was conducted in accordance with ASTM C 295. Los Angeles Abrasion of Aggregates A Los Angeles Abrasion test was conducted on one bulk sample collected at the ground surface within the proposed borrow areas. This test method evaluates the aggregates resistance to abrasion using a standardized testing machine. Los Angeles abrasion testing was conducted in accordance with ASTM C 131/C 535. Stetson Creek Diversion and Cooper Lake Dam Facilities Report of Geotechnical Engineering Services – Revised Draft March 2011 Soundness of Aggregates The soundness of a selected bulk sample was evaluated to determine the aggregate’s resistance to weathering. The selected bulk sample was collected at the ground surface at the location of a proposed borrow area. This test simulates the effect of weathering by subjecting the sample to either sodium sulfate or magnesium sulfate for a minimum of five cycles. The soundness of aggregate testing was conducted in accordance with ASTM C 88. APPENDIX III 2010 Geophysical Seismic Refraction Survey and Video Core Logging Program . Stetson Creek Diversion and Cooper Lake Dam Facilities Report of Geotechnical Engineering Services – Revised Draft March 2011 APPENDIX III 2010 GEOPHYSICAL SEISMIC REFRACTION SURVEY AND VIDEO CORE LOGGING PROGRAM As part of a design level exploration program, MWH conducted five geophysical seismic refraction surveys (SL-10-1-1, SL-10-1-2, SL-10-2, SL-10-3 and SL-10-5). The surveys were conducted by Northwest Geophysical Associates of Corvallis, Oregon, between July 28 and July 30, 2010. Geophysical surveys were located in the field using Global Positioning System-based survey equipment with sub-meter accuracy. The geophysical survey locations are shown on the Figure 2 of this report. Video televiewer core logging was conducted on borings B-2-2010 and B-5-2010. Details are provided in the report of geophysical services attached. Northwest Geophysical Associates, Inc. 1600 SW Western Boulevard, Suite 200 PO Box 1063, Corvallis, OR 97339-1063 Phone: (541) 757-7231 FAX: (541) 757-7331 www.nga.com October 26, 2010 NGA Ref: 744 Paul D. Richards, P.E. Senior Geotechnical Engineer MWH Americas, Inc. 5100 SW Macadam Ave, No. 420 Portland, Oregon 97239 2010 Geophysical Investigation Stetson Creek Diversion Project Kenai Peninsula Borough, Alaska Dear Mr. Richards: This letter report presents the results of the seismic refraction and borehole televiewer survey that Northwest Geophysical Associates, Inc. (NGA) performed for the Stetson Creek Diversion Project (Figure 1 – Site Location) near Cooper Lake, Kenai Peninsula Borough, Alaska. This is a follow up investigation to the seismic refraction survey which NGA performed in fall of 2009. That work was presented to MWH in a report dated October 28, 2009. The Stetson Creek Diversion Project will include a diversion dam on Stetson Creek and pipeline from the diversion dam to Cooper Lake. The geophysical investigation was to aid MWH America’s geotechnical investigations of site conditions along the pipeline route, at the Cooper Lake spillway structure, and at the Stetson Creek diversion structure. The geophysical work included two tasks: 1) seismic refraction on 4 lines in the Stetson Creek canyon and 2) optical televiewer logging of borings at the Stetson Creek diversion structure and at the Cooper Lake spillway. Results of the two tasks are presented as separate sections of this report. SEISMIC REFRACTION The objective of the seismic refraction survey was to estimate depth-to-bedrock as well as to characterize overburden and bedrock materials with seismic velocities. An NGA technical note describing the seismic refraction method is attached (Attachment A). 2010 Geophysical Investigation Page 2 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 26, 2010 Field Methodology Field work was performed along four seismic lines during the period July 27-29, 2010. The locations of the four seismic lines (Lines SL10-1, SL10-2, SL10-3, and SL10-5) are shown on Figure 2, Seismic Line Locations. The seismic lines are numbered as proposed with the prefix “10” added to the number to differentiate the 2010 seismic lines from the 2009 seismic lines. Line SL10-1 crosses Stetson Creek at the diversion dam site, and SL10-2, SL10-3 and SL10-5 run along the pipeline alignment on the east side of Stetson Creek approximately 400, 1200 and 2200 feet downstream from the diversion dam respectively. SL10-4 was omitted due to time and access constraints at the time of the field survey. The proposed seismic line alignments were surveyed and brushed by an independent surveyor prior to the geophysical field work. Survey lath marking the start and end of the 300 foot long alignment were placed by the surveyors. Actual seismic geophone locations were then referenced to those endpoints using a 300-fiberglass tape. Final seismic line locations, as well as the surveyed alignment endpoints, are shown on Figure 2. NGA measured relative elevations along each line using a handheld inclinometer and measuring tape. Those relative elevations were tied to the surveyed elevations of the alignment endpoints. The seismic field investigation was performed using a 24-channel Geometrics Geode seismograph to record the data. A 30kg slide hammer was used as the primary seismic source to generate a seismic wave at regular intervals along each seismic line and also at some distance from both ends of each line. On SL10-1-1 NGA used 24 geophone receivers spaced at 5 foot intervals, yielding a line length of 115 feet. On SL10-1-2 NGA used 20 geophone receivers spaced at 5 foot intervals, yielding a line length of 95. At SL10-2, -3, and -5 NGA used 24 geophone receivers spaced at 10 foot intervals, yielding a line length of 230 feet. INTERPRETATION RESULTS The results of the seismic survey are shown on the interpretated profiles (Figures 3-6). The profiles show the geophone locations along the ground surface, the interpreted depths/thicknesses of each layer, and interpreted velocities. Seismic Stratigraphy Interpretations For these seismic lines along Stetson Creek we see the same basic units as those reported in the 2009 survey along the pipeline alignment closer to Cooper Lake. Those units are summarized in Table 1: 2010 Geophysical Investigation Page 3 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 26, 2010 TABLE 1 Seismic Stratigraphy GRAPHIC PATTERN LAYER DEISGNATION & SEISMIC VELOCITY POSSIBLE CLASSIFICATION (Feet/Second) Dot Fill V1 - 300 – 1,200 V1 - Unconsolidated soil and/or organic material. Angled Hatch V2 - 2,150 – 2,800 V2 – Poorly consolidated overburden, landslide material. Solid Grey V3 - 4,200 – 13,000 Weathered or Competent Rock (Phyllite – Slate, per conversation with MWH). Seismic Profile Interpretations Seismic Line 10-1 Seismic Line 10-1 was run crossing Stetson Creek at the planned site of the diversion structure. The line was run in two spreads with SL10-1-1 on the left bank to the west and SL10-1-2 on the right bank to the east. Both spreads used a 5-foot geophone spacing. The spread lengths were 115 and 95 feet (slope distance) respectively. Geophone elevations were measured in the field with a handheld inclinometer. However, the final interpretation used elevations taken from the topographic map, Figure 2. The interpretation shows a low velocity surface layer (300 ft/sec to 1,200 ft/sec). This corresponds to a thick organic mat and possibly some unconsolidated slide material. The lower layer velocities, 7,000 ft/sec and 4,200 ft/sec, are interpreted as bedrock and weathered bedrock. A phyllite-slate is observed at the surface in the two boreholes on that line, B1 and B2. Data quality on this line was fair, with strong attenuation in the organic mat and excessive seismic noise due to the fast flowing creek. 2010 Geophysical Investigation Page 4 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 26, 2010 Seismic Line 10-2 The interpreted seismic profile for Seismic Line 2, extending 230 linear feet, is displayed on Figure 4. Seismic Line 2 was run along the east side of Stetson Creek 400 feet north (downstream) of the proposed diversion dam site. The line was run on a steep side slope. The seismic interpretation indicates the presence of lower velocity materials: V1=1,000 ft/sec and V2=2,600 ft/sec. These layers combined are 3 to 10 feet thick and are interpreted as organic materials overlying slide deposits. Layer 3 is interpreted as competent bedrock with a representative velocity of 8,600 ft/sec. Seismic Line 10-3 The interpreted seismic velocity profile for Seismic Line 3, extending 230 linear feet, is displayed on Figure 5. Seismic Line 3 was run along the east side of Stetson Creek 1200 feet downstream (north) of the proposed diversion dam site. The line was run on a steep side slope. No bedrock velocities were observed at this site. The velocities of 1,000 ft/sec and 2,150 ft/sec are interpreted as organic mat and poorly consolidated, possibly landslide materials. Seismic Line 10-5 The interpreted seismic velocity section for Seismic Line 5, extending 230 linear feet, is displayed on Figure 4. Seismic Line 5 was run along the east side of Stetson Creek 2,200 feet downstream of the proposed diversion dam site. The line was run on a steep side slope. The interpretation shows competent bedrock, with velocities of 13,000 ft/sec, at depths from 50 to 60 feet. Above that is a thick overburden, possibly poorly consolidated landslide debris. Resolution of Interpretation While the accuracy of the interpretation depends on site-specific conditions, geophysical methods in general provide an accuracy of +/- 10% under good conditions. Extreme changes in topography or depth to subsurface interfaces will affect the accuracy. As with any geophysical technique, these results are interpretive in nature and represent the best estimate of subsurface conditions considering the limitations of the geophysical method employed. Only direct observations using borings or test pits or other means can ultimately characterize subsurface conditions, using the geophysical results as a guide. 2010 Geophysical Investigation Page 5 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 26, 2010 TELEVIEWER LOGGING Field Methodology Field work was performed at two borehole locations during the period July 25-26, 2010. Borehole B-2 is located on the right bank (east side) of Stetson Creek at the proposed diversion damn site. Borehole B-5 is located in the Cooper Lake spillway adjacent to the existing dam on the west end of Cooper Lake. It was originally planned to log four borings: B1 and B2 at the diversion structure and B4 and B5 at the Cooper Lake spillway. However, the high water in Stetson Creek at the time of the survey prevented access to B1 on the left bank of the creek. Boring B4 at the spillway was plugged at a depth of approximately 6 feet and the logging tools could not get past that depth. The borehole logging was performed using a Mount Sopris/ALT model OBI40 Optical Borehole Televiewer, and a Poly Caliper Probe. A Matrix Portable Digital Logger console and side-by-side winch were used to control those probes. The caliper log, which measures the diameter of the borehole, was run prior to the televiewer to assure that the boring was not obstructed. Caliper boring diameter information was also used to correct the dip angles measured from the televiewer logs. Both borings were water filled to within 2 feet of the surface. Boring logs have been corrected to true north using the magnetic declination of 18.7° E. The depth is referenced to the ground surface at the boring. Televiewer Interpretation Results Televiewer images are presented in Figures 7 and 8 for borings B2 and B5 respectively. Regular foliation can be seen in both borings. We have indicated strike and dip of several of the foliation features in each log. The foliation direction was very consistent within each borehole. Boring B2 foliation generally had a dip direction of about 290° with dips near 70°. Boring B5 foliation generally had a dip direction of about 100° with dips near 70°. Those directions are referenced to the true north direction. CLOSURE Northwest Geophysical Associates, Inc. has performed this work in a manner consistent with the level of skill ordinarily exercised by members of the profession currently practicing under similar conditions. No warranty, express or implied, beyond exercise of reasonable care and professional diligence, is made. This report is intended for use only in accordance with the purposes of the study described within. 2010 Geophysical Investigation Page 6 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 26, 2010 Please feel free to contact us if you have any questions or comments regarding this information, or if you require further assistance. We appreciated the opportunity to work with you on this project and look forward to providing you with geophysical services in the future. Sincerely, Northwest Geophysical Associates, Inc. Rowland French, R.G. President Attachments: Figures 1-8 Attachment A: Seismic Refraction Technical Note File: CooperLake 2010_Rpt02.doc NGA Project: 744 ELEVATION (feet) ELEVATION (feet) ELEVATION (feet) ELEVATION (feet) APPENDIX IV 2009 Test Pit Procedures, Logs, and Photographs . Stetson Creek Diversion and Cooper Lake Dam Facilities Report of Geotechnical Engineering Services – Revised Draft March 2011 APPENDIX IV 2009 TEST PIT PROCEDURES, LOGS, AND PHOTOGRAPHS As part of a previous exploration program, MWH conducted 12 test pit excavations (TP-1 through TP-12). Each test pit was excavated using a Komatsu PC-120, track-mounted excavator on October 5 and 6, 2009. The excavator was operated by Dan Hayes of D&R Construction of Seward, Alaska. Test pits were backfilled with excavated soil and compacted to the extent feasible with the excavator. Test pit locations were determined in the field using a hand-held Global Positioning System receiver and by pacing from features identified on site drawings. Test pit elevations shown in the explorations logs were based on elevation values shown on available topographic surveys of the site. Test pit locations are shown on Figures 2,3 and 15 of the report. Test pit locations and elevations should be considered approximate. Soils encountered were classified in accordance with the ASTM D 2488, Practice for Description and Identification of Soils (Visual-Manual Procedure). Soil samples were collected directly from the test pit or from the bucket of the excavator at selected locations and depths. Collected samples were packaged and shipped to laboratories for testing in general accordance with the procedures outlined by ASTM D 4220, Standard Practices for Preserving and Transporting Soil Samples. Exploration logs and photographs of test pits TP-1 through TP-12 are presented in the following pages. Letter Name Hatching GW Well-graded gravels or gravel-sand mixtures, little or no fines T GP Poorly-graded gravels or gravel-sand mixtures, little or no fines GM Silty gravels, gravel-sand-silt mixtures D GC Clayey gravels, gravel-sand-silt mixtures SW Well-graded sands or gravelly sands, little or no fines Ring Sample: 1.5" ID ring sampler R SP Poorly-graded sands or gravelly sands, little or no fines Grab Sample G SM Silty sands, sand-silt mixtures Bulk Sample B SC Clayey sands, sand-silt mixtures ML Inorganic silts & very fine sands, rock flour, silty or clayey fine sands, or clayey silts with slight plasticity Moisture Content M CL Inorganic clays of low to medium plasticity, gravelly clays, sandy or silty clays, lean clays Grain Size Analysis GS OL Organic silts and organic silt-clays of low plasticity Atterberg Limits A Corrosion Testing C Sand and Sandy Soils Laboratory Test Type Fine-grained SoilsSilt, Clay, Silty Soils, Clayey Major Divisions Symbol Sample Type Coarse-grained SoilsGravel and Gravelly Soils Standard Penetration Test: split spoon sampler, 2.0" OD/ 1-3/8" ID, driven with 140 lb. weight, 30" drop Modified California Sampler: Split spoon sampler, 3.0" OD, driven with 140 lb. weight, 30" drop MH Inorganic silts and organic silt-clays of low plasticity Corrosion Testing C CH Inorganic clays of medium to high plasticity, organic silts OH Peat and other highly organic silts Pt Peat and other highly organic soils Sandstone Siltstone Claystone Shale or Chert Water level at time of exploration Fill Fill-landfill refuse Equilibrated water level FillFine-grained SoilsClayey Soils Bedrock PROJECT NO. 1007059Geotechnical Investigation Report Stetson Creek Diversion and Cooper Lake Outlet Chugach Electric Association, Inc. Anchorage, Alaska UNIFIED SOIL CLASSIFICATION SYSTEM AND EXPLORATION LOG EXPLANATION LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: 1195.1 ft TP-1 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: 1195.1 ft TP-1 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: 1184 ft TP-2 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: 1184 ft TP-2 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-3 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-3 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-4 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-4 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-5 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-5 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-6 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-6 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-7 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-7 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-8 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-8 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-9 DATE DRILLED: Oct. 5, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-9 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 6, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-10 DATE DRILLED: Oct. 6, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-10 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 6, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-11 DATE DRILLED: Oct. 6, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-11 LOG OF EXPLORATION NO. DATE DRILLED: Oct. 6, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-12 DATE DRILLED: Oct. 6, 2009 EQUIPMENT: Komatsu PC-120 Excavator ELEVATION: TP-12 APPENDIX V 2009 Laboratory Testing Program and Results Stetson Creek Diversion and Cooper Lake Dam Facilities Report of Geotechnical Engineering Services – Revised Draft March 2011 APPENDIX V 2009 LABORATORY TESTING PROGRAM The 2009 geotechnical laboratory soil testing was conducted by Duane Miller Associates of Anchorage, Alaska. Corrosion-related analytical laboratory testing was submitted to TestAmerica Inc. (TAI) of Anchorage, Alaska. TAI’s corrosion testing was conducted in their Beaverton, Oregon, Laboratory. All tests were conducted in accordance with applicable ASTM or U.S. Environmental Protection Agency (EPA) testing standards. Descriptions of the laboratory tests conducted on selected soil samples are presented below. Test results are summarized in the 2009 exploration logs in Appendix IV and are detailed in the following pages. Moisture Testing Moisture content tests were performed on a number of samples recovered from the test pits. The results of these tests were used to aid in evaluating soil properties. Moisture content tests were conducted in accordance with ASTM D 2216. Sieve Analysis Sieve analyses (combined sieve with hydrometer analyses) were performed on selected samples of the subsurface materials. These tests were performed to evaluate the gradation characteristics of the soils and to aid in their classification. These tests were performed in accordance with ASTM D 422. Atterberg Limits Testing (Liquid Limit, Plastic Limit and Plasticity Index) Atterberg limits are used primarily for classifying and indexing cohesive soil. The liquid and plastic limits, which are defined as the moisture content of a cohesive soil at established limits for liquid and plastic behavior, respectively, were determined for a core material sample from Cooper Lake Dam. Atterberg limits testing was conducted in accordance with the guidelines presented in ASTM D 4318. Plasticity Index (PI) is defined as the difference in water content between the liquid limit (LL) and plastic limit (PL). Soil Classification Visual soil classifications were conducted on all soil samples in the field and confirmed with laboratory testing. All soils were classified in accordance with the Unified Soil Classification System as described by ASTM D 2487 and ASTM D 2488 as appropriate, which includes: stiffness/ relative density, color, major soil type (based on grain size), minor soil types, and relative moisture content. Classifications and sampling intervals are shown in the test pit exploration logs presented in Appendix IV of this report. The logs indicate the depths at which the soils or their characteristics change at the location of the exploration, although the changes may actually be gradual. If the change occurred between sample locations, the depth of change was interpreted. APPENDIX VI 2009 Geophysical Seismic Refraction Survey Program . Stetson Creek Diversion and Cooper Lake Dam Facilities Report of Geotechnical Engineering Services – Revised Draft March 2011 APPENDIX VI 2009 GEOPHYSICAL SEISMIC REFRACTION SURVEY PROGRAM As part of the 2009 exploration program, MWH conducted nine geophysical seismic refraction surveys (SL-1 through SL-9). The surveys were conducted by Northwest Geophysical Associates of Corvallis, Oregon, between September 29 and October 2, 2009. Geophysical surveys were located in the field using Global Positioning System-based survey equipment with sub-meter accuracy. The survey locations are shown on Figure 2 of this report. Details are provided in the report of geophysical services attached. Northwest Geophysical Associates, Inc. 1600 SW Western Boulevard, Suite 200 PO Box 1063, Corvallis, OR 97339-1063 Phone: (541) 757-7231 FAX: (541) 757-7331 www.nga.com October 28, 2009 NGA Ref: 715 Paul D. Richards, PE Senior Geotechnical Engineer MWH Americas, Inc. 5100 SW Macadam Ave, No. 420 Portland, Oregon 97239 Final Report Geophysical Investigation Stetson Creek Diversion Project Kenai Peninsula Borough, Alaska Dear Mr. Richards: This letter report presents the results of the seismic refraction survey that Northwest Geophysical Associates, Inc. (NGA) performed for the Stetson Creek Diversion Project (Figure 1 – Site Map) near Cooper Lake, Kenai Peninsula Borough, Alaska. NGA was assisted in the field effort by Mr. Thomas Williams of Northland Geophysical PLLC. The Stetson Creek Diversion Project will include a diversion dam on Stetson Creek and pipeline from the diversion dam to Cooper Lake. The geophysical investigation was to aid MWH America’s geotechnical investigations of site conditions along the pipeline route, potential borrow locations at Cooper Lake, the Cooper Lake Dam, and the pipeline terminus at Cooper Lake. The objective of the investigation was to estimate depth-to-bedrock as well as to characterize overburden and bedrock materials with seismic velocities. A description of the seismic refraction method is attached (Attachment A). Interpreted results are described in this report and presented on Figures 2-10. Field Methodology Field work was performed along nine seismic lines during the period September 29, 2009 to October 2, 2009. The locations of the nine seismic lines (Lines SL-1 through SL-9) are shown on the Site Map (Figure 1). The seismic lines are numbered in the order they were run in the field, with SL-1 at the proposed borrow area near Cooper Lake Dam, SL- Geophysical Investigation Page 2 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 28, 2009 2 at the spillway next to Cooper Lake Dam, and SL-3 at the pipeline lake access location. Seismic lines 4-9 are along the pipeline alignment. The locations of the seismic lines were selected by Paul Richards of MWH. The seismic lines were established in the field using 300-foot tape measures. NGA mapped the positions of the line ends using a Trimble PRO XRS GPS, which has sub-meter accuracy. NGA measured relative elevations along each line using a transit level. The field investigation was performed using a 24-channel Geometrics Geode seismograph to record the data. A Betsy Seisgun was used as the primary seismic source, firing an 8 gauge shotgun blank (400 grains of black powder) with the muzzle 2-3 feet into the surface soils to generate a seismic wave at regular intervals along each seismic line, and also at some distance from both ends of each line. Where surface soils were shallow (Seismic Lines 1-3), a slide-hammer (30 kg weight) source was used to generate a seismic wave at regular intervals along each seismic line, and also at some distance from both ends of each line. Geophones were spaced at 10-foot intervals along each of the seismic lines. On Seismic Lines 1, 2, and 5-10 NGA used 24 geophone receivers spaced at 10 foot intervals, yielding line lengths of 230 feet. On Seismic Line 3 NGA used 14 geophone receivers spaced at 10 foot intervals, yielding a line length of 130 feet due to limited physical access (e.g. thick forest and lake water) on either end of the survey alignment. At Seismic Line 4 NGA used 22 geophone receivers spaced at 10 foot intervals, yielding a line length of 210 feet due to limited physical access (e.g. rock wall and thick forest) on either end of the survey alignment. Interpretation Results The results of the seismic survey are shown on the interpretation profiles (Figures 2-10). The profiles show the geophone locations along the ground surface, the interpreted depths/thicknesses of each layer, and interpreted velocities. The possible geologic units were identified based on the interpreted seismic velocities (in feet/second) and conversation with MWH engineer Paul Richards. Their interpreted velocity range (in feet per second), graphic pattern, and possible classification are indicated in the following table. Geophysical Investigation Page 3 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 28, 2009 TABLE 1 Seismic Stratigraphy GRAPHIC PATTERN LAYER DEISGNATION & SEISMIC VELOCITY POSSIBLE CLASSIFICATION (Feet/Second) Dot Fill V1 - 820 – 1,460 V1 - Unconsolidated soil and/or organic material. Angled Hatch V2 - 2,700 – 3,250 V2a – 4,900 – 6,850 V2 - More consolidated overburden and/or weathered material. V2a – Till and/or slide material. Solid Grey 8,500 – 16,000 Competent Rock (Phyllite – Slate, per conversation with MWH). Seismic Stratigraphy Interpretations Layer 1 – Organic and unconsolidated soil overburden Layer 1exhibits lower velocities ranging from 820 feet/second to 1,460 feet/second. We have interpreted this layer as organic and unconsolidated soil overburden. Layer 1 was observed on all nine seismic profile alignments with the exception of Seismic Line 2, at the dam spillway. Layer 1 thickness varied across the individual profile alignments, usually representing the upper 2-8 feet of the interpreted profile. Layer 2 –Consolidated overburden material Layer 2 displayed moderate velocities ranging from 2,700 feet/second to 3,200 feet/second. We have interpreted this layer as overburden material. Layer 2 was observed on Seismic Lines 3, 8, and 9. Layer 2 thicknesses varied greatly across the site and even across individual profiles, with layer thickness ranging from 10 to 25 feet Layer 2a –Till and/or Slide Material Layer 2a displayed moderate to high velocities ranging from 4,900 feet/second to 6,800 feet/second. We have interpreted this layer as till and/or slide material. Layer 2a was observed only on Seismic Lines 1 and 7. Where interpreted, Layer 2a thickness was substantial (20 feet or greater) and extended near the maximum depth of the interpreted seismic profiles. Geophysical Investigation Page 4 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 28, 2009 Layer 3 – Competent Rock The high velocities exhibited by Layer 3 ranged from 8,500feet/second to 16,000 feet/second. We have interpreted this layer as competent rock, likely correlated to the phyllite-slate material common throughout the site. Layer 3 was interpreted across eight of the nine profile alignments: Seismic Lines 1-6 and 8-9. Layer 3 was not observed on Seismic Line 7. The interpreted competent rock layer (Layer 3) has a range of high seismic velocities (8,500 – 16,000 ft/sec). These values likely correlate to the phyllite- slate material observed throughout the site, and are in the range of values for similar rock units observed elsewhere in the Chugach Formation. Profile Interpretations Seismic Line 1 The interpreted seismic velocity profile for Seismic Line 1, extending 230 linear feet, is displayed on Figure 2. Seismic Line 1 was run across a flat surface northeast of the existing dam at the northern end of Cooper Lake, a location being considered for material excavation and supply. A low velocity (1,100 feet/second) material, which we have interpreted as Layer 1, appears in the upper 5 feet of the profile alignment. The interface between Layer 1 and Layer 2a mirrors the generally flat surface topography. A zone of moderate velocity material (6,850 feet/second) was observed nearly to the maximum depth of investigation (approximately 50-60 feet). We have interpreted this moderate velocity zone as Layer 2a (till). As access was clear off the ends of this alignment, and data from near off end shot points indicated a possible third layer beneath the interpreted Layer 2a, NGA collected data from far off end shotgun shell energy sources. These additional data were taken at distances approximately 100 feet off either end of the spread, distances which were not possible on any of the other seismic alignments due to limiting physical surface features (e.g. rock walls, dense forest). Additional data from these far off end data points seems to indicate the presence of a third layer at depths of 45 feet and greater; however, at such interpretation depths and source distances off the end of the seismic receiver array, resolution of the third layer was limited. As a result of this limited resolution, NGA has indicated the Layer 2a-Layer 3 contact with a dashed interpreted contact line on Figure 2. The estimated representative velocity for velocity Layer 3 and dipping (from West to East) interface contact represent the best model available from the data that were collected. As the interface contact and velocity layer are near the depth limit of investigation with available energy sources, their actual depth, interface geometry, and material velocities may vary from the interpretations we have provided. Geophysical Investigation Page 5 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 28, 2009 Seismic Line 2 The interpreted seismic velocity section for Seismic Line 2, extending 230 linear feet, is displayed on Figure 3. Seismic Line 2 was run along the long axis of the spillway at the west end of the existing dam at the northern end of Cooper Lake. Interpretation of the seismic data indicates the presence of a single high velocity layer. We have interpreted this material as velocity Layer 3 (competent rock), and estimate a representative velocity of 15,000 feet per second. Seismic Line 3 The interpreted seismic velocity section for Seismic Line 3, extending 130 linear feet, is displayed on Figure 4. Seismic Line 3 was run at the site where the proposed pipeline outfall to Cooper Lake. The west end of the seismic alignment was bounded by dense forest, and the east end of the seismic alignment terminated near the edge of Cooper Lake, leaving only a 130 foot survey alignment. Interpretation of the seismic data indicates the presence of three velocity layers across the alignment which itself slopes significantly on its eastern half. Velocity Layer 1 (organic material and unconsolidated overburden) exhibited a low velocity (820 feet/second) and varied from 1-5 feet in thickness, generally mirroring the sloping topography. Velocity Layer 2 (consolidated overburden) exhibited a moderate velocity (2,400 feet/second) and layer thickness of approximately 20 feet. The upper limit of velocity Layer 2 tapers with the sloping topography on the east end of the profile while the lower limit of velocity Layer 2 trends gently downward from west to east between stations 0 and 60, and remains fairly flat from station 60 to station 130. The faster material (11,100 feet/second) interpreted below velocity Layer 2 to the maximum depth of detection we have interpreted as velocity Layer 3 (competent rock). Seismic Lines 4-6 The interpreted seismic velocity sections for Seismic Lines 4, 5, and 6, extending 210, 230, and 230 linear feet respectively, are displayed on Figures 5, 6, and 7 respectively. Seismic Lines 4-6 were run at different locations along the proposed pipeline alignment which runs between Stetson Creek and Cooper Lake (Figure 1). Interpretation of the seismic data indicates the presence of two velocity layers across each of these profile alignments. We have interpreted the low velocity (820-880 feet/second) material in the upper 2-8 feet of each of these profiles as velocity Layer 1 (organic material and unconsolidated overburden) and the high velocity material (13,000- 13,900 feet/second) extending from beneath Layer 1 to the maximum interpretation depths (20-40 feet below ground surface) of each profile alignment as velocity Layer 3 (competent rock). The Layer 1 – Layer 3 contacts for all three profiles generally mirror Geophysical Investigation Page 6 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 28, 2009 the topography profile, except at the topographic low which appears along Seismic Line 5 at station 35. As this topographic low occurs at a creek/stream crossing, it is likely that Layer 1 is missing from the interpreted section due to erosion. Seismic Line 7 The interpreted seismic velocity section for Seismic Line 7, extending 230 linear feet, is displayed on Figure 8. Seismic Line 7 was run along a section of the proposed pipeline alignment which runs between Stetson Creek and Cooper Lake (Figure 1). Interpretation of the seismic data indicates the presence of two velocity layers. We have interpreted the lower velocity material (1,460 feet/second) as velocity Layer 1 (organic material and unconsolidated overburden), which appears along other interpreted sections across the site. Layer 1 is approximately 10 feet in thickness, and generally mirrors surface topography at depth. We have interpreted the layer of moderate velocities (4,900 feet/second) beneath velocity Layer 1 as possible till or slide material. This layer, Layer 2a, is similar to materials found at similar depths on Seismic Line 1. While exhibiting a significant velocity contrast from velocity Layer 1, Layer 2a does not fall within the range of the interpreted competent rock values seen in Layer 3 elsewhere across the site, but instead better fits a range of values more commonly exhibited by till and/or slide materials. Seismic Line 8 The interpreted seismic velocity section for Seismic Line 8, extending 230 linear feet, is displayed on Figure 9. Seismic Line 8 was run along a section of the proposed pipeline alignment which runs between Stetson Creek and Cooper Lake (Figure 1), and is located between Seismic Lines 6 and 7. Similar to Seismic Lines 4-6, Seismic Line 8 exhibits a thin (2 feet) zone of low velocity (1,050 feet/second) material at the surface, and a zone of fast velocity (14,700 feet/second) material at depth. We have interpreted these two zones as velocity Layer 1 (organic material and unconsolidated overburden) and velocity Layer 3 (competent rock). Similar to Seismic Line 3, Seismic Line 8 also exhibits a zone of moderate velocity (2,750 feet/second) between Layers 1 and 3. The Layer 1-Layer 2 contact mirrors surface topography while the Layer 2-Layer 3 contact gradually thickens at depth from west (station 230) to east (station 0) across the profile alignment. We have interpreted this zone as velocity Layer 2 (consolidated overburden). Seismic Line 9 The interpreted seismic velocity section for Seismic Line 9, extending 230 linear feet, is displayed on Figure 10. Seismic Line 9 was run along a section of the proposed pipeline Geophysical Investigation Page 7 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 28, 2009 alignment which runs between Stetson Creek and Cooper Lake (Figure 1), and is located between Seismic Lines 4 and 5. Seismic Line 9 exhibited three velocity zones of 925 feet/second, 3,250 feet/second, and 8,500 feet/second, which we have interpreted as velocity Layers 1, 2, and 3 respectively. The layers have respective thickness of 1-2 feet, 6-8 feet, and <15 feet while the interface boundaries mirror the irregular and undulating surface topography. We have interpreted the layers as organic and unconsolidated soils, consolidated overburden, and competent rock respectively. While the interpreted velocity for Layer 2, 3,250 feet/second best corresponds to consolidated overburden; a second interpretation is that this material can be related to velocity Layer 2a (till and/or slide material). Resolution of Interpretation While the accuracy of the interpretation depends on site-specific conditions, geophysical methods in general provide an accuracy of +/- 10% under good conditions. Extreme changes in topography or depth to subsurface interfaces will affect the accuracy. As with any geophysical technique, these results are interpretive in nature and represent the best estimate of subsurface conditions considering the limitations of the geophysical method employed. Only direct observations using borings or test pits or other means can ultimately characterize subsurface conditions, using the geophysical results as a guide. CLOSURE Northwest Geophysical Associates, Inc. has performed this work in a manner consistent with the level of skill ordinarily exercised by members of the profession currently practicing under similar conditions. No warranty, express or implied, beyond exercise of reasonable care and professional diligence, is made. This report is intended for use only in accordance with the purposes of the study described within. Geophysical Investigation Page 8 Stetson Creek Diversion Project, Kenai Peninsula Borough, Alaska October 28, 2009 Please feel free to contact us if you have any questions or comments regarding this information, or if you require further assistance. We appreciated the opportunity to work with you on this project and look forward to providing you with geophysical services in the future. Sincerely, Northwest Geophysical Associates, Inc. Rowland French, R.G. President Neil McKay Project Geophysicist Attachments: Figures 1-10 Attachment A: Seismic Refraction Technical Note File: CooperLake_Rpt02.doc NGA Project: 715 RELATIVE ELEVATION (feet) RELATIVE ELEVATION (feet) RELATIVE ELEVATION (feet) RELATIVE ELEVATION (feet) RELATIVE ELEVATION (feet) RELATIVE ELEVATION (feet) RELATIVE ELEVATION (feet) RELATIVE ELEVATION (feet) RELATIVE ELEVATION (feet) Seismic Refraction Survey Stetson Creek Diversion Project Kenai Peninsula Borough, Alaska Attachment A NGA Technical Note Seismic Refraction Northwest Geophysical Associates, Inc. P.O. Box 1063, Corvallis, OR 97339-1063 (541) 757-7231 Fax: (541) 757-7331 www.nga.com info@nga.com © 2006 Northwest Geophysical Associates, Inc. Geophysical Services Environmental Groundwater Geotechnical Seismic Refraction TECHNICAL NOTE COVER rev.2B, AUG. 2006 Depth-to-Bedrock Competence of Bedrock Fault Mapping Groundwater Investigations © Northwest Geophysical Associates, Inc. DISCUSSION OF GEOPHYSICAL TECHNIQUES Revision: August 2006 SEISMIC REFRACTION Page 1 HEAD WAVE DIRECT WAVE RECIEVERS SEISMIC SOURCE REFRACTED WAVE IMPULSIVE WAVE BEDROCK OVERBURDEN Figure 1 Seismic Refraction Geometry DISCUSSION OF GEOPHYSICAL TECHNIQUES SEISMIC REFRACTION INTRODUCTION Seismic refraction is a commonly used geophysical technique to determine depth-to- bedrock, competence-of-bedrock, depth-to- water table, or depth to other seismic velocity boundaries. Seismic refraction is widely used in geotechnical and groundwater investigations. It is one of the classic geophysical techniques, presented in most introductory geophysical courses and texts. PHYSICAL PRINCIPLES The seismic refraction technique is illus- trated in the schematic drawing, Figure 1. An impulsive source creates a seismic wave (sound wave), which travels through the earth. When source to receiver separation is small, the first arrival is generally the direct wave propagating through the surface layer. When the wave-front reaches a layer of higher velocity (e.g. bedrock), a portion of the energy is refracted, or bent, and travels along the refractor as a head wave, at the seismic velocity of the refractor (bedrock). Energy from the propagating head wave leaves the refractor at the critical angle of refraction and returns to the surface, where its arrival is detected by a series of geophones and recorded on a seismograph. The angle of refraction depends on the ratio of velocities in the two materials (Snell’s Law). Travel times for the impulsive wave-front to reach each geophone are measured from the seismograph records. From those travel times, seismic velocities in each layer, and depths to each layer can be cal- culated. Seismic refraction differs from seismic reflection, which is widely used in petroleum exploration. In reflection seismic the waves re- flected off the geologic interface are utilized rather than the refracted arrivals. FIELD PROCEDURES When acquiring seis- mic refraction data a series of 12 or 24 geophones (re- ceivers) are placed along the seismic line at set intervals, the geophone interval. Each of these set-ups of 12 or more geophones is termed a spread. The geophone interval is generally 5 to 50 feet de- pending on the desired resolution and the desired depth of exploration. Due to the geometry of refraction (governed by Snell’s Law), it is necessary for the length of © Northwest Geophysical Associates, Inc. DISCUSSION OF GEOPHYSICAL TECHNIQUES Revision: August 2006 SEISMIC REFRACTION Page 2 the seismic spread to be approximately 3 to 5 times the depth of the overburden in order to detect the primary refractor (i.e., the bedrock). A series of 5 to 11 shots are initiated for each spread, one at each end, one or more be- yond the ends (off end), and one or more along the spread. These additional shotpoints allow dipping interfaces, changes in overburden mate- rials, and intermediate layers to be identified and resolved, increasing the accuracy of the depth- to-bedrock interpretation. Several spreads may be put together to form a longer refraction profile line. Several options are available for the seismic energy source. A sledge hammer strik- ing an metal plate is one of the simplest and most common sources. An airless jackhammer (Figure 2) provides additional energy and may be effective if the bedrock is 30 or 40 feet, par- ticularly if the overburden is sufficiently con- solidated. A higher energy source, such as an elastic weight drop (Figure 3) or 8-gauge seis- mic shells, may be required if the overburden is loose and poorly consolidated, or if the bedrock interface is significantly deeper. Small explo- sive charges may be used where depth of explo- ration, near surface attenuation, or high ambient noise demand a stronger source. DATA PROCESSING & INTERPRETATION Processing begins with picking the time of the first arrival. While several automated picking programs are available, the first arrival times must be checked for accuracy and consis- tency and adjusted as needed. Two basic methods of processing first arrival data are available, each with its strengths and limitations. These can be classified as delay-time techniques and tomographic tech- niques. Figures 4 and 5 show delay-time and tomographic interpretations of the same data. Figure 2 Airless Jack Hammer Figure 3 Elastic Weight Drop © Northwest Geophysical Associates, Inc. DISCUSSION OF GEOPHYSICAL TECHNIQUES Revision: August 2006 SEISMIC REFRACTION Page 3 Delay-Time Techniques Delay-time methods treat the earth as discrete layers, with refracted waves coming off each layer. Generally, these methods assume laterally continuous, constant velocity repre- sentations of the subsurface. Delay-time methods are sometimes referred to as the plus- minus method or the time-term method. The generalized reciprocal method (GRM) is based on the delay-time approach. Historically, the delay-time is the classic method of interpreting seismic refraction data. Redpath, 1973, is an excellent reference for the basic delay-time technique. Picked first arrivals are assigned a specific subsurface layer from which that seismic wave was refracted. This is a critical step in the interpretation process. Layer as- signment is based on the slope of the travel-time curves and the recognition of parallel curve segments from adjacent shots. Reduced traveltimes are calculated using refracted arrivals from each direction, effec- tively removing changing layer thickness on the velocity curve and leading to a better velocity 101091010910108101081010710107101061010610105101051010410104101031010310102101021010110101OAK CREEKOAK CREEK -20 00 100 DISTANCE (FEET)DEPTH (FEET)20-20 20 40 60 80 120 SOUTHWEST NORTHEAST -20 00 100 DISTANCE (FEET)DEPTH (FEET)20-20 20 40 60 80 120 SOUTHWEST NORTHEAST V1 = 1100 ft/secV1 = 1100 ft/sec V2 = 6100 ft/secV2 = 6100 ft/sec Figure 4 Layered Earth Interpretation SEISMIC P-WAVE VELOCITY FT/SEC 1200 1800 2400 3000 3600 4200 4800 5400 6000-20 00 100 DISTANCE (FEET)DEPTH (FEET)20-20 20 40 60 80 120 SOUTHWEST NORTHEAST Figure 5 Tomographic Interpretation © Northwest Geophysical Associates, Inc. DISCUSSION OF GEOPHYSICAL TECHNIQUES Revision: August 2006 SEISMIC REFRACTION Page 4 determination. Refractor depth is computed from the velocity and delay time, at each geophone. A common enhancement to the delay time method is to refine the model, using ray tracing. The ray tracing procedure adjusts the depth of the interface at the point the ray enters or emerges from the refractor. Tomographic Techniques Tomographic techniques partition the earth model into a mesh of finite-element or finite-difference elements, each with an assigned velocity. Element velocities are iteratively adjusted, altering the theoretical ray path(s) through the model. Velocities are adjusted until a best fit between the observed travel-times, and the modeled travel-times is arrived at. Tomographic methods evolved rapidly in the late 1990s (Zhu et al., 2000). Today there are several commercial software packages available. Each has its own variation of the inversion method, choice of the starting model, and introduction of geologic constraints(see Sheehan et al., 2005). Tomographic solutions allow for both lateral and vertical changes in velocity. Thus, they can approximate complex geologic situa- tions such as faulting and weathering. However, where sharp geologic/velocity boundaries are present, tomographic interpretations will tend to represent them as gradational boundaries. Tomographic solutions are inherently non-unique. Several earth models may yield similar travel-time curves. Therefore, it is often useful to look at the layered earth/delay-time solution along with the tomographic solution and geologic constraints to select the most appropriate. APPLICATIONS The product or deliverable from a seismic refraction survey is generally a profile, or cross section, along the seismic line showing depth-to- bedrock (or other primary refractor) at each geophone, and seismic velocities in the bedrock and the overburden. Often layers with interme- diate velocities (corresponding to layers or units with varying consolidation or lithology) can be identified and resolved. Seismic velocities relate to the soundness or competence of rock, and to the degree of con- solidation, cementation, and/or saturation in soils. The Caterpillar Tractor Co. has developed a series of tables which empirically relate seismic velocities to the rippability of bedrock with their equipment (such as a D8 or D9 with one or several ripper teeth). Figure 6 is an example of those rippability tables. In geotechnical engineering, depth-to- bedrock and rippability surveys are commonly used for design and cost estimates for road cuts, pipelines, and other civil engineering projects. Groundwater applications of seismic refraction include mapping bedrock channels, identifying faults and fracture zones, and delineation of geologic boundaries to constrain hydrogeologic models. LIMITATIONS There are several inherent limitations to the seismic refraction technique. Fortunately, for most projects, the required geologic condi- tions are met, and the seismic refraction program can be successfully. However, these conditions must always be considered when planning a refraction survey, and when examining refraction data. Velocity contrast A velocity contrast between strata is re- quired to refract the seismic wave. Hence, similar stratigraphic units are difficult to differentiate. Weathering zones with grada- tional changes present problems. Tomo- graphic techniques can now handle some of the weathering zone problems © Northwest Geophysical Associates, Inc. DISCUSSION OF GEOPHYSICAL TECHNIQUES Revision: August 2006 SEISMIC REFRACTION Page 5 Velocity reversals Standard refraction velocity analysis as- sumes that the velocity of successive layers increases with depth. Hidden layers Thin layers with small velocity contrast between adjacent layers may be hidden lay- ers, and no first arrival refracted from that layer will be present. These layers are diffi- cult to detect without additional borehole data. Lateral velocity variations Most standard interpretation software does not do a good job at handling geology with gross lateral variations in lithology. Fault zones can be detected from slower velocities in the brecciated fault gouge zones, but of- ten are poorly imaged unless a detailed sur- vey with short geophone spacing is carried out. Shot points coverage Tomographic models require dense shot coverage to properly constrain the models. This is an operational or cost constraint rather than a constraint inherent in the method. Urban Noise Urban noise (traffic, railways, construction, etc.) and natural noise (wind, waves, moving water, etc.) often limit the depth of ex- ploration, or dictate a more energetic source. D9L Ripper Performance Multi or Single Shank Ripper Estimated by Seismic Wave Velocities TOPSOIL CLAY GLACIAL TILL IGNEOUS ROCKS SEDIMENTARY ROCKS METAMORPHIC ROCKS MINERALS & ORES GRANITE BASALT TRAP ROCK SHALE SANDSTONE SILTSTONE CLAYSTONE CONGLOMERATE BRECCIA CALICHE LIMESTONE SCHIST SLATE COAL IRON ORE RIPPABLE MARGINAL NON-RIPPABLE Velocity in Meters Per Second x 1000 Velocity in Feet Per Second x 1000 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 2 3 4 Taken From: Caterpillar Performance Handbook, 1983 Caterpillar Tractor Company Note: Seismic compression wave analysis serves as only one indicator of rippability and the only proven test is a machine trial. Figure 6 Example of Caterpillar Rippability Tables © Northwest Geophysical Associates, Inc. DISCUSSION OF GEOPHYSICAL TECHNIQUES Revision: August 2006 SEISMIC REFRACTION Page 6 Borehole or ground truth data is very use- ful in constraining the seismic interpretation. Seismic data is often used very effectively to interpolate between borings or to extrapolate away from borings. Downhole seismic veloci- ties surveys are even more effective at constraining refraction interpretations. FURTHER READING: Caterpillar Tractor Company, 2004, Caterpillar Performance Handbook, Edition 35, Peoria, Illinois. Dobrin, M.B. and Savit, C.H., 1988, Intro- duction to Geophysical Prospecting, 4th Edition, McGraw-Hill, New York, NY, 867 pp Kassenaar, Dirk, and John Luttinger, 1993, Practical considerations in GRM refraction surveys in glacial terrains: in Proceedings of the Symposium on the Application of Geophysics to Engineering and Environmental Problems, Environmental and Engineering Geophysical Society, San Diego, California, April 18-22, pp. 355-371. Langston, Robert W., 1990, High Resolution refraction seismic data acquisition and interpretation:in Ward, S., ed., Geotechnical and Environmental Geophysics, Society of Exploration Geophysicists, Tulsa, OK, pp. 45-73. Palmer, Derecke, 1980, The Generalized Reciprocal Method of Seismic Refraction Interpretation: Society of Exploration Geophysicists, Tulsa, Oklahoma, 104 pp. Redpath, Bruce B., 1973, Seismic Refraction Exploration for Engineering Site Investigations: U.S. Army Engineer Waterways Experiment Station, Explosive Excavation Research Laboratory, Livermore, California, Technical Report E- 73-4, (NTIS AD-768710) 51 pp. Sheehan, J. R., Doll, W. E. and Mandell, W. A., 2005, An Evaluation of Methods and Available Software of Seismic Refraction Tomography Analysis, Journal of Environmental and Engineering Geophysics, v.10(1):21-34. Zhu, T., Cheadle, S., Petrella, A., and Gray, S., 2000, First-arrival tomography: method and application: Expanded Abstracts SEG 70th Annual Meeting, 2028-2031p. DISCUSSION OF GEOPHYSICAL TECHNIQUES SEISMIC REFRACTION Northwest Geophysical Associates, Inc. P.O. Box 1063 Corvallis, Oregon 97339 http://www.nga.com phone: (541) 757-7231 Rowland B. French, PhD, R.G. Senior Geophysicist Mark J. Villa Project Geophysicist Revision: August 2006 Printed :August 4, 2006 refraction_teq_2006-08A.doc APPENDIX VII Selected Historical Exploration Logs