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Whitman Lake Hydroelectric Project Feasibility Study August 1998 Final Report
WHITMAN LAKE HYDROELECTRIC PROJECT FEASIBILITY STUDY Ketchikan Public Utilities August 1998 Final Report WESCORP WHITMAN LAKE HYDROELECTRIC PROJECT FEASIBILITY STUDY Ketchikan Public Utilities August 1998 Final Report WESCORP WHITMAN LAKE HYDROELECTRIC PROJECT FEASIBILITY STUDY Table of Contents Section Page EXECUTIVE SUMMARY «000.20... 2c. istessecseseersecssssssescstsscesseses i 1 PROJECT DESCRIPTION Project Location and Existing Facilities... eee 1-1 Site Specific Factors Considered in the Project Layout ............. 1-1 Preferred Project Arrangement................:.::escceseeeeeeeeeeneeeees 1-2 2 BASIN HYDROLOGY EEREPCRCICITEIED | etdetcrtateeesdtesictate nstascloaie anteereeleicie ala ete snicrerersicarieters 2-1 Methodology............... 2-1 Inflow to Whitman Lake .00....... cece eee ceeeeeeeeeeeesteeeteeeeseneeeeneeees 2-2 3 ENERGY GENERATION ANALYSIS Plant Operation Assumptions ................:ceeceeseeteeeeteeeeteeeeneeeeneeees 3-1 Methodology................ceee we de Average Annual Energy. 1 3-2 Plant Factor...............ccsscccsscssssesccerssetcoseceseseeerees 1. 3-2 Comparison With Existing Generation Resources. ................... 3-3 4 PROJECT COST ESTIMATE Direct Construction and Investment Costs Basis of Cost Estimate ..........0.. ee ae KPU / SSRAA Agreement ............. ce ceseesseesceeeecsseesesseseseeesene 5 COST OF ENERGY ANALYSIS First Year Cost of Energy «2. 5-1 Sensitivity AnalySis .......0..... cece cceeseceeecseecseeseecseeeeeeeeeeseeneeeees 5-1 6 PROJECT DEVELOPMENT SCHEDULE .......000.0.... cece 6-1 7 ENVIRONMENTAL AND REGULATORY ISSUES Introduction 7-1 Water Quality and Quantity .. wo Fisheries...........0...::cceeeeeee 2 T3 Botanical Resources... kl SIRI FRIRRIII eselcatanss oniosnitectalcinns-ssasneetene ens extiansnnsas seoruadnenenseanenie 7-6 Table of Contents (Continued) Section Page 7 ENVIRONMENTAL AND REGULATORY ISSUES Land Use and Ownership.......... oe 7-10 Recreational Resources . 7-11 Visual Resources ............... 7-12 Historic/Cultural RESOUICES ...........ececeeeseeceseeeeeeeeeteeeeseeeeeteee 7-13 FERC Licensing Alternatives..........................:.--csccscceeosesensoeeee 7-14 8 CONCLUSIONS AND RECOMMENDATIONS ......0000...oc eee 8-1 APPENDIX A - Alternative Project Configurations APPENDIX B - Geotechnical Report APPENDIX C - Turbine Vendor Cost Data EXECUTIVE SUMMARY EXECUTIVE SUMMARY WHITMAN LAKE HYDROELECTRIC PROJECT FEASIBILITY STUDY INTRODUCTION In August 1997, Ketchikan Public Utilities (KPU) retained WESCORP to conduct an engineering study to determine the feasibility of developing three hydroelectric power projects in the Ketchikan area. This report presents the results of the study for the Whitman Lake Project. Whitman Lake is located about 4 miles east of Ketchikan, Alaska. KPU’s decision to study the hydropower potential at Whitman Lake was based on conclusions and recommendations presented in KPU’s 1996 Power Supply Planning Study prepared by R.W. Beck in December 1996. Based on the recommendations, KPU applied for, and received, a Preliminary Permit from the Federal Energy Regulatory Commission (FERC). Obtaining the Preliminary Permit was the first step in the FERC licensing process, and provides KPU priority over any competing License Application during the three year term of the permit. BASIS OF ANALYSIS The study findings and conclusions presented herein were based on the following principal objectives, criteria and assumptions: 1. Determine the optimum project arrangement that would generate the greatest average annual energy for the least cost. 25 The project would be operated primarily in response to lake inflow. Maximizing the annual energy output from the project was considered more important than developing firm capacity to help meet peak power demands. 3: KPU will be able to utilize the full energy generating capability of the plant by year 2003, the scheduled on-line date. 4. The existing water rights held by the Herring Cove Hatchery and Herring Cove Water Association shall not be adversely impacted. Also, the hatchery’s existing control of water temperature and water chemistry shall not be impacted. 5. The selected project arrangement and mode of operation should be compatible with the existing fishery resource, and should provide a reasonable balance between the value of energy and value of environmental resources to the region and local community. Whitman Lake Hydroelectric Project i Feasibility Study August 1998 RECOMMENDED PROJECT ARRANGEMENT Four alternative project arrangements were analyzed with the principal difference being the method in which water is conveyed from Whitman Lake to a new powerhouse located at Herring Cove. The conveyance alternatives were: 1) A lake tap and tunnel arrangement, 2) A surface penstock following generally the same alignment as the existing water supply pipelines from Whitman Dam to the hatchery. 3) Utilizing the existing hatchery pipelines together with a new surface penstock paralleling the pipelines. 4) A least cost arrangement, with no integration of the hydro facilities with the existing hatchery. The first two project alternatives listed above were initially studied and described in the January 1998 draft report. The third and fourth alternatives were evaluated, at the request of KPU, after submitting the draft report. Based on detailed analysis of the four project arrangements, the third alternative listed above is recommended for development, and is hereinafter referred to as the “Preferred Alternative”. The project will consist of the following major elements: 1. Existing Whitman Dam. This 40-foot high concrete gravity dam was constructed in 1927 at the outlet to Whitman Lake, and provides 2,500 acre- feet of regulated storage capability. The volume of storage is equivalent to 17 days of average inflow to the lake with no releases from the dam. Some work will be needed to rehabilitate the existing dam to ensure its long- term stability and reliability. The recent dam safety inspection report identified, among other things, a concern with leakage though concrete joints, and measures to monitor or correct the problem. 2: New 45-inch diameter penstock. The new steel penstock will be 2,220 feet in length and will generally follow the same alignment of the two existing water supply pipelines from the dam to the existing vacuum valve house. The penstock will need to be buried up to a maximum depth of about 20 feet near the valve house to ensure that the penstock has sufficient pressure head to convey the full design flow to the turbines. Ss Two new diversion structures. The natural drainage area into Whitman Lake is 4.1 square miles. A portion of the flow from two creeks that do not naturally flow into the lake will be diverted to the lake via small diameter pipelines in order to increase the amount of flow available for power generation. The two diversions combined will effectively augment the natural basin flow by 30 percent. Whitman Lake Hydroelectric Project ii Feasibility Study August 1998 4. Powerhouse. A 2,800 square foot composite concrete and steel-framed powerhouse will be located immediately uphill from the existing PRV building. The powerhouse will contain a 3.9 MW unit and a 0.7 MW unit for a total installed capacity of 4.6 MW. The larger unit will operate within a flow range between 50 and 150 cfs, and the small unit will operate between 12 and 30 cfs. Both turbines will be horizontal Francis type machines, which are the most appropriate type unit with the given head and flow conditions. In order to suppress the magnitude of hydraulic transient pressures in the penstock when flow is abruptly changed, an 18-inch diameter synchronous bypass valve will be installed to automatically open if the turbine wicket gates suddenly close due to a line fault or other reasons. Tailwater level exiting the powerhouse will be controlled at about El. 40 for the small unit, and at El. 20 for the larger unit. Discharge from the small unit will be conveyed to the hatchery. 5: Switchyard and Transmission Line. The plant switchyard will be located adjacent to the powerhouse and will contain a power transformer, circuit breakers and disconnect switches. About 1,200 feet of existing distribution line will need to be reconductored. AVERAGE ANNUAL ENERGY The project will annually generate an average of 19,641,000 kWh. Average annual energy was determined based on synthesizing monthly streamflow records from actual USGS monthly and daily records on Beaver Falls Creek and Mahoney Creek because there do not exist any long-term actual streamflow records above the mouth of Whitman Creek. The Beaver Falls and Mahoney Creek basins are located immediately north of the Whitman Lake basin and are similar to the Whitman basin in size, terrain, average elevation and orientation to prevailing winds. The close similarities and proximity of these three basins provided an excellent basis from which to develop synthetic streamflow data for the Whitman Lake basin. Based on an installed plant capacity of 4.6 MW, the project will operate at a 49 percent plant factor. DEVELOPMENT SCHEDULE Project development will occur in three major phases; licensing, final design/contract documents, and construction. The project will need to be licensed with FERC prior to beginning construction. KPU currently holds a Preliminary Permit, issued by the Federal Energy Regulatory Commission, to study the project. It is currently anticipated that an application for license could be submitted to FERC by May 2000, assuming no major issues arise during the licensing process requiring lengthy study. Assuming a normal licensing process, without any major surprises, the project could be place into service by December 2003. CONSTRUCTION COST ESTIMATE A construction cost estimate was prepared based on experience data and vendor budget quotes for major equipment and materials. Turbine and generator costs were Whitman Lake Hydroelectric Project iii Feasibility Study August 1998 determined based on review of budget quotations from five reputable turbine vendors. Vendor quotes for steel pipe, the synchronous bypass valve and the steel-framed powerhouse superstructure were also obtained. Based on engineering analysis of the recommended project arrangement, and a January 1998 bid price level, the Direct Construction Cost, including contingency, is estimated to be $6,349,000. The Total Investment Cost, including engineering, interest during construction and escalation to a 2002 bid date, is estimated to be $8,786,000. COST OF ENERGY The Total Capital Requirements (bond issue size), and first year annual cost was determined based on 20 year bonds sold at 6 percent annual interest. Total Capital Requirements are estimated to be $9,964,000, and the first year annual cost is $1,006,000. The annual cost includes debt service, earnings on reserves, operation and maintenance, administration and general expenses, FERC compliance expenses, plant interim replacements and insurance. Based on an average annual delivered energy of 19,641,000 kWh, the first year cost of power is 5.1 cents per kWh. CONCLUSIONS Based on the studies conducted for this feasibility report, the following conclusions can be made: 1; The Whitman Lake Hydroelectric Project is technically and economically feasible, and can be constructed without significant adverse environmental impacts. 2. The preferred project arrangement includes rehabilitation measures to existing Whitman Dam, constructing two diversion structures, a new 2,220-foot long steel penstock, a powerhouse containing two units totaling 4.6 MW of capacity, a switchyard and 1,200-foot long transmission line. 3. Design of the recommended project arrangement can be made compatible with the operating objectives of the Herring Cove hatchery and local water user’s association. 4. The project will generate 19,641,000 kWh of deliverable energy on an average annual basis. 5. The Total Investment Cost for the project is $8,786,000 based on escalation to a year 2002 bid date. 6. First year cost of power is 5.1 cents per kWh. 7 The project can be placed into service by December 2003. Whitman Lake Hydroelectric Project iv Feasibility Study August 1998 SECTION 1 Project Description SECTION 1 PROJECT DESCRIPTION PROJECT LOCATION AND EXISTING FACILITIES Whitman Lake is located near the southeast end of Revillagigedo Island, approximately four miles east of the City of Ketchikan, Alaska, as shown on Fig. 1-1. The lake is naturally formed, but the normal water surface elevation was raised about 18 feet in 1927 with the construction of a 46-foot high concrete gravity arch dam at the lake outlet. The dam was originally part of a 1,500 kW hydroelectric project owned by New England Fish Company. The Ketchikan Utilities Board purchased the project in 1957 and the plant was retired from service shortly thereafter. The original penstock and powerhouse have, for the most part, been demolished and removed from the site, but the dam remains in service providing water supply to the Herring Cove Fish Hatchery, owned and operated by the Southern Southeast Regional Aquaculture Association, Inc. (SSRAA), and to the Herring Cove Water User’s Association for domestic use. Existing facilities currently in operation include the dam and two parallel above-ground steel pipelines supplying water to the hatchery. Both pipelines are about 2,260 feet in length. The larger pipeline is 24 inches in diameter at the dam, and reduces to 18 inches diameter over the lower 900 feet. The smaller pipeline is 10 inches in diameter at the dam, and reduces to 8 inches over the lower 900 feet. In addition to these facilities, a small concrete diversion structure is located on Whitman Creek about 3,000 feet downstream of Whitman Dam to supply water for domestic use to 21 homeowners in the Herring Cove area. SITE SPECIFIC FACTORS CONSIDERED IN THE PROJECT LAYOUT In developing project layouts the following were considered: ile The December 8, 1978 Water and Land Use Agreement between SSRAA and KPU contemplated future hydro development of Whitman Lake and provides SSRAA the right to take water downstream of the future powerhouse, or upstream if the two parties agree. 2 Minimize impacts to current water temperature and chemistry controls at the hatchery. 3. Minimize impacts to the Herring Cove Water User's Association water right. 4. The elevation of the original lake outlet, at about El 362, presents a physical constraint to reservoir operation. Whitman Lake Hydroelectric Project 1-1 Feasibility Study August 1998 5. Resource agencies will likely require a minimum instream flow release from the lake. 6. The existing hatchery complex presents both physical and access constraints for siting project facilities. We Penstock design and hydraulics need to consider a high point in the existing pipeline about 1300 feet downstream from the dam. PREFERRED PROJECT ARRANGEMENT In its 1996 Initial Draft Power Supply Planning Study, R.W. Beck investigated several preliminary design concepts for developing the power potential at Whitman Lake. Those concepts were reviewed for this present study, together with other concepts, to make an initial judgment on which arrangements appeared to be the most promising. Based on initial review of information and site conditions, four alternative project arrangements were given further consideration with the principal differences being the method in which water is conveyed from Whitman Lake to a new powerhouse located at Herring Cove and integration of the project with existing hatchery operations. After evaluating the technical, economic and environmental attributes of the four alternative project arrangements, a preferred arrangement was selected. The preferred arrangement (hereinafter referred to as the Preferred Alternative) is described below, and the three other alternatives are presented in Appendix A. General Description The Preferred Alternative involves constructing a new 45” steel penstock from Whitman Dam to a powerhouse at Herring Cove containing two turbine/generator units totaling 4.6 MW. The penstock will follow the same general alignment as the existing hatchery water supply pipelines. The general layout of project facilities is shown on Fig. 1-2. Dimensions and sizes of principal project features are presented in Table 1- 1. Specific features are described as follows: Existing Whitman Dam The existing 70-year old dam shows signs of deterioration, but with proper rehabilitation measures and maintenance, it can be made a reliable structure through one or several 30 year FERC license terms. In the most recent dam safety inspection report, published in January 1997, it was reported that areas of leakage were observed through the dam, which may indicate potentially deteriorating concrete joints. It was recommended that the leakage be monitored and the joints be eventually grouted. Since the dam will become an important feature of the hydro project, dam repairs and maintenance items should include, at a minimum, grouting the joints, repairing rock pockets, painting exposed metalwork, and installing new safety grating and railings on the dam crest. Whitman Lake Hydroelectric Project 1-2 Feasibility Study August 1998 Table 1-1 Project Statistics Preferred Alternative Drainage Area Natural Drainage Area Diversion Area (2 sites) Average Annual Natural Outflow at Dam Combined Average Annual Flow at Diversion Sites Reservoir Normal Maximum Operating Elevation Normal Minimum Operating Elevation Active Storage at El. 380 Surface Area at El. 380 Surface Area at El. 362 Existing Dam Dam Type Maximum Structural Height Crest Length Dam Crest Elevation Spillway Type Spillway Crest Elevation Spillway Width Outlets Penstock Existing Pipelines New Penstock Diameter/Length Powerhouse Type Size (footprint) Unit 1: (Horizontal Francis) Rated Capacity Rated Head Maximum Discharge Unit 2: (Horizontal Francis) Rated Capacity Rated Head Maximum Discharge Transmission Line Voltage Length Whitman Lake Hydroelectric Project 1-3 Feasibility Study 4.1 square miles 1.25 square miles 78 cfs 23 cfs 380 362 2,500 acre-feet 148 acres 129 acres Concrete Gravity Arch 46 feet 220 feet 385 Ogee Sill within Dam 380 40 feet 2-36” dia. and 1-42” dia. 18-inch / 2,260 feet 8-inch / 2,260 feet 45-inch / 2,220 feet Above Ground Concrete 2,800 sq. ft. 3,900 kW 345 feet 150 cfs 700 kW 310 feet 30 cfs 34.5 kV 1,200 feet August 1998 Based on recent dam safety inspection reports, it appears that the structural stability of the dam has been analyzed, but possibly not to standards required by FERC for licensed hydroelectric projects. Development of a hydroelectric project utilizing Whitman Lake may require additional structural analysis of the dam under seismic and Probable Maximum Flood loading conditions in accordance with FERC’s Engineering Guidelines. If results from previous analyses do not meet FERC’s accepted methods and factors of safety, then such analyses will be required. Remove Timber Crib Dam When Whitman Dam was constructed in 1927 it inundated a timber crib dam located immediately upstream. Remnants of the timber crib dam are still visible below the water surface. Based on a 1926 sketch showing the location of both dams, the crest of the timber crib dam was set at about El. 370, or about 8 feet above the proposed minimum operating pool level. In order to ensure sufficient flow is made available to the Whitman Dam intake down to the proposed minimum operating pool level, El. 362, any flow restrictions caused by the timber crib dam, large trees, root balls or other material, will need to be removed. New Diversion Structures The natural drainage area into Whitman Lake is 4.1 square miles. A portion of flow from two creeks that do not naturally flow into the lake will be diverted to the lake via small diameter pipelines in order to increase the amount of flow available for power generation. The two diversions combined will augment the natural basin inflow by as much as 30 percent. A plan of these diversions is shown on Fig. 1-2. One of the diversions will be located about 1,300 feet northeast of Whitman Dam on a tributary that feeds Whitman Creek below the dam. The diversion structure will be capable of diverting up to 35 cfs through a 1,600-foot long, 24- inch diameter, high density polyethylene (HDPE) pipe. The drainage area above the diversion site is 0.95 square miles. The second diversion site will be located about 4,800 feet southwest of the dam on a creek that flows to Herring Cove. The drainage area above this diversion is 0.3 square miles. Streamflow up to 10 cfs will be diverted to Whitman Lake via a 16-inch diameter, 1,760-foot long, HDPE pipe. Both diversions will be rockfill structures constructed from boulders, rock fragments and gravel that can be easily excavated nearby. The diversion structure will have a concrete or HDPE liner blanket on the upstream face to act as an impervious barrier. Future field studies should investigate the availability of sufficient clay as an alternative impervious barrier. At each diversion there will be a small gated intake structure, spillway slot with flashboards, and a gated sluice pipe. All gates will be manually operated. The Whitman Lake Hydroelectric Project 1-4 Feasibility Study August 1998 intake gate will be normally in the full open position and will be used primarily to dewater the diversion pipeline for maintenance or repair. Sediment, tree limbs and other debris that collects behind the diversion structure will need to be periodically removed by sluicing or manual means. It may be possible to “walk-in” a small dozer to construct the larger diversion, but materials and equipment will need to be hauled in by air to construct the smaller diversion. Because of the higher cost of hauling equipment and materials by air, and the relatively smaller drainage area, future studies should confirm the economic feasibility of constructing the smaller diversion. The diversion pipelines will be laid at a 1 to 2 percent slope generally following the contours of the land. The pipe will be buried or mounded where feasible to provide protection from falling trees or boulders. The pipe will be anchored to minimize displacement. During the study a third diversion site was considered. The site is located north of Whitman Lake and would divert a portion of streamflow below the outlet of two small lakes at El. 1850. After further study the diversion site was eliminated from consideration for three reasons. First, field observations indicated the terrain to be steeper and more difficult for pipeline construction and long-term maintenance than expected. Second, based on discussions with fishery resource agencies, the potential for costly fishery studies and mitigation was apparent. Lastly, Tongass Coast Aquarium, Inc. has plans to utilize a portion of the streamflow for freshwater needs at the aquarium as well as its own small hydropower project. It was concluded that these factors, combined with the limited amount of flow that would actually be diverted, indicate this diversion alternative would not provide any marginal benefits to the project. New 45-inch Diameter Penstock A new 45-inch diameter, 2,220-foot long, steel penstock will be constructed from the dam to the powerhouse at Herring Cove. A plan and profile of the new penstock is shown on Fig. 1-3. The penstock will be supported above ground on piers founded on bedrock. Based on geotechnical evaluation of the penstock route (Appendix B), an above ground penstock is more suitable due to the presumed shallow depth to bedrock. It will generally parallel the same alignment of the two existing water supply pipelines from the dam to the existing vacuum valve house. At the valve house, about 200 feet of the new penstock will be buried up to a maximum depth of about 20 feet to ensure that the penstock has sufficient pressure head to convey the full design flow to the turbines. The buried section of penstock will likely require rock blasting. Existing Hatchery Pipelines The two existing pipelines serving the hatchery’s water supply and temperature requirements will continue to serve these functions. The existing valves at the dam used to control temperature and flow rate will be automated to make Whitman Lake Hydroelectric Project 1-5 Feasibility Study August 1998 operations more convenient for the hatchery. Instead of delivering water to the hatchery at high pressure, a small turbine unit will be installed on the lower end of the existing pipelines to convert the high potential energy to useful kinetic energy. In order to optimize the amount of hydroelectric generation, the lower 890 feet of the existing 18-inch diameter pipeline will be replaced with 24-inch diameter pipe. The proposed design concept would maintain the same flow rate to the hatchery that they currently require, but the flow will be under a lower pressure head. This will require replacing some of the hatchery piping with larger diameter pipe in order to convey the hatchery’s current maximum flow rate. Other design challenges that will need to be addressed in order to integrate the hatchery’s water supply needs with the hydro project's needs include minimizing nitrogen supersaturation and ensuring that dissolved oxygen levels do not become too low. Benefits that SSRAA could realize from constructing the project include automatation of existing inlet valves serving the hatchery, replacement of about 900 feet of 18-inch diameter pipeline with 24-inch diameter pipe, better knowledge of available lake storage during critical low flow periods, and possibly a reduction in the magnitude of de-gassing required because the turbines will not entrain any significant volume of air into the water. Intake Connection There are three existing outlets through the dam. Two 36-inch diameter outlets have inverts at about El. 349, and a single 42-inch diameter outlet has an invert at about El. 354. The 42-inch outlet and one of the 36-inch outlets are currently being used to collectively supply up to 27 cfs to the hatchery. Flow through the outlets is manually regulated to control the temperature of water delivered to the hatchery. The 42-inch outlet draws from the top portion of the lake and the 36-inch outlet draws from deeper waters through an approximate 1,500-foot pipe connected to it on the upstream side. The unused 36-inch outlet will serve as the inlet to the new 45-inch diameter penstock. Further study will be needed to determine if the existing outlet could be enlarged to provide better hydraulic conditions at the intake. A trashrack will be installed on the upstream face of the dam to prevent large woody debris from entering the penstock and potentially damaging the turbine runner. Instream Flow Release Valve In order to maintain flow in the channel below the dam, a remote operated 8- inch diameter throttling valve will be tapped into the new penstock and the existing 24-inch pipeline at the dam to enable a continuous flow of 4 cfs below the dam. A 4 cfs instream flow is assumed at this time to satisfy fishery concerns and water rights held by the Herring Cove Water User’s Association. The assumed instream flow rate appears reasonable based on negotiated rates at other nearby projects. However, the actual rate of flow will be subject to negotiation during preparation of the FERC license application. Whitman Lake Hydroelectric Project 1-6 Feasibility Study August 1998 Powerhouse A 2,800 square foot composite concrete and steel-framed powerhouse will be located immediately uphill from the existing PRV building. A site plan of the powerhouse and hatchery facilities is shown on Fig. 1-4. The powerhouse will contain a 3.9 MW unit and a 0.7 MW unit for a total installed capacity of 4.6 MW. The larger unit will operate within a flow range between 50 and 150 cfs, and the small unit will operate between 12 and 30 cfs. Both turbines will be horizontal Francis type machines, which are the most appropriate type unit with the given head and flow conditions. In order to suppress the magnitude of hydraulic transient pressures in the penstocks when flow is abruptly changed, an 18-inch diameter synchronous bypass valve will be installed to automatically open if the turbine wicket gates suddenly close due to a line fault or other reasons. A plan and section view of the powerhouse is shown on Fig. 1-5. Tailwater level exiting the powerhouse will be controlled at about El. 40 for the small unit, and at El. 20 for the larger unit. Discharge from the small unit will be conveyed to the hatchery for its use, with any excess flow diverted to the lower tailrace. Discharge from the large unit will be conveyed in a buried concrete box culvert running from the powerhouse to a point immediately east of the existing fish ladder entrance. Discharging adjacent to the fish ladder will minimize any confusion to returning fish. Switchyard and Transmission Line The plant switchyard will be located adjacent to the powerhouse and will contain a power transformer, circuit breakers and disconnect switches. Transmission line work will involve reconductoring approximately 1,200 feet of the existing distribution line serving the hatchery and several residences along Powerhouse Road. The 34.5 kV transmission line will be constructed from the switchyard to an intertie with the 34.5 kV Beaver Falls line along Tongass Highway. Plant Operation A main premise of this alternative is that plant operation, in response to reservoir inflow, takes precedence over the operation of all other KPU-owned generating resources. KPU would still purchase power from the Swan Lake Project in accordance with terms under the Four-Dam Pool Agreement. Adopting this operating philosophy will maximize energy generation and minimize spill. Because of the relative lack of storage with this project alternative, the project will operate similar to a run-of-river project, which more or less respond to inflow rather than load. A reservoir level sensing device, installed at the dam and hard-wired to the powerhouse, will periodically transmit water surface elevation and rate of change in elevation to a programmable logic controller (PLC) in the powerhouse. The PLC will transmit a signal to gradually open or close the Whitman Lake Hydroelectric Project 1-7 Feasibility Study August 1998 turbine wicket gates based on a series of pre-programmed logical arguments that take into account variables such as current rate of reservoir inflow, current reservoir level, target reservoir level, hatchery flow demand, and optimum turbine efficiency. Programming the units to respond to reservoir inflow will make more efficient use of inflow and reduce spill. For example, if an inflow of 400 cfs to the reservoir (not an unusual event) were sustained for 4 hours, the reservoir would rise about 1 foot in that time period assuming there were no releases from the dam. If sustained over 24 hours, then the rise would be 6 feet. With reservoir level sensing, wicket gates on the two units would automatically open in an effort to maintain the targeted reservoir level until the full combined maximum turbine discharge of 180 cfs is attained. The reservoir level would still rise because inflow (400 cfs) exceeds outflow (180 cfs), but the rise over 24 hours would be only about 3 feet versus 6 feet. This type of operation will reduce overall spill. Hatchery Operation The hydroelectric project will be hydraulically integrated with the hatchery’s water supply needs. Water for the hatchery will continue to be taken from the two existing pipelines, however the larger (18” diameter) pipeline will be connected to the 700 kW turbine unit. Water from the small (8-inch diameter) pipeline will not be used for hydropower generation, but will continue to feed the hatchery. Typical monthly hatchery water demands, according to SSRAA, are presented in Table 1-2. Table 1-2 Typical Hatchery Water Demands, cfs Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Spt | Oct | Nov | Dec 18” pipeline To raceways 25 25 25] 20 20 8 15 26 tet 25 25 To incubation | 1.6 | 1.6 0.9] 0.9 | 0.5 2. 0 0 | 05 | 2:5 | 2.5 | 2:5 8” pipeline To raceways 0 0 0 0 0 0 0 0 0 0 0 0 To incubation | 3.1 | 3.1 | 2.2 | 2.2 | 1.4 CO [i474 273 [ie ec E Total 29.7 | 29.7 | 28.1 | 23.1 | 21.9 | 10 | 17.2 | 28.2 | 27.7 | 32.6 | 30.6 | 30.6 Potential Construction Impacts on Hatchery Operations Construction of the hydro project will be an inconvenience to hatchery personnel and operations, but with proper construction planning and scheduling there should be no need to cause any significant disruption or loss of production. The greatest risk to fish production will occur if there is an interruption in the water supply or temperature Whitman Lake Hydroelectric Project Feasibility Study 1-8 August 1998 control capability. This risk can be reduced by carefully specifying in the construction contracts what construction time windows will be acceptable, such as time of year and allowable number of consecutive days, hours or minutes for certain interruptions. Other potential impacts may include elevated noise and dust levels around the hatchery, inconveniences caused by the movement and storage of additional heavy equipment and supplies close to existing hatchery buildings, and potential contamination of the water supply through work on the intakes, dam, and submerged timber crib dam. Construction specifications will describe the safeguards needed to minimize these potential construction impacts. Whitman Lake Hydroelectric Project 1-9 Feasibility Study August 1998 ¥ TALBOT. LAKE, of REVILLAGIGEDO ISLAND QO MAHONEY LAKE Lake Vg = PERSEVERANCE f- UPPER ql METCHKAN '@ LOWER SILIS LAKE ED CARLANNA LAKE (Pp LOWER KETCHIKAN 2 UPPER SILUS LAKE KETCHIKAN, GRAVINA ISLAND PROJECT LOCATION ALASKA , \ ° | ANCHORAGE ey i) zl Z \uneau <a PROJECT LOCATION KETCHIKAN a v Oa Q ea PAIGE MOLCIE ALN) KEY MAP KETCHIKAN PUBLIC UTILITIES WHITMAN LAKE HYDROELECTRIC PROJECT FERC PROJECT NO. 11597 PROJECT LOCATION MAP FIGURE 1-1 WESCORP WHITMAN LAKE NORMAL MAX. W.S. EL 380 _. *—"ExIsTING WHITMAN LAKE DAM SCALE IN FEET KETCHIKAN PUBLIC UTILITIES WHITMAN LAKE HYDROELECTRIC PROJECT FERC PROJECT NO. 11597 PROJECT GENERAL ARRANGEMENT FIGURE 1-2 NEW 34.5-kV JANSMISSION LINE / \ \\ / re / ee PLAN SCALE: 1"=400° 400 ORIGINAL GROUND ube =a _ 320 = + | \ | N PENSTOCH € GRAPHIC SCALE: x 240 # | \ z \ 400 0 400 é el < \ SCALE IN FEET az 160 a 100 0 ; | ee - . + + \ SCALE IN FEET | | \ 80 KETCHIKAN PUBLIC UTIUTIES | | \ POWERHOUSE WHITMAN LAKE HYDROELECTRIC PROJECT | } | = FERC PROJECT NO. 11597 | | | | | | | || L | | | | ft |_| | PENSTOCK PLAN AND PROFILE 3 | 0+00 5+00 10+00 15+00 20+00 25+00 30+00 FIGURE 1-3 STATION PROFILE ALONG € PENSTOCK SCALE: HORIZ. 1"=400° VERT. 1"=100" WESCORP chsme 18” STEEL “= — a — | EXISTING 8* STEEL PIPELINE =~ NEW POWERHOUSE ;—~ | NEW ACCESS ROAD NEW SWITCHYARD —$\ — LOT 31 INCUBATION ~~ _ BUILDING SHOP) - | | YA | RACEWAYS Y + : i \\ — NEW TAILRACE | SN F'SH LADDER SCALE IN FEET KETCHIKAN PUBLIC UTILITIES WHITMAN LAKE HYDROELECTRIC PROJECT FERC PROJECT NO. 11597 POWERHOUSE AREA LAYOUT FIGURE 1-4 weyers 40'-0 j 780 kVA EXISTING 8"@ TEMPERATURE CONTROL PIPELINE CENERATOR S| vie 24"@ SUPPLY LINE 3 TO HATCHERY zi ° —— it : 8 GEN. FLR. oe EL. 45.0 NEW 24°6 TEMPERATURE CONTOL PIPELINE (REPLACES EXISTING 18°8 PIPELINE) J 1 co 7 —=—STAIRS H z < = it [2 18"@ SYNCHRONOUS ir BYPASS er - fv aes y 15 NEW 45"@ STEEL PENSTOCK oS MH 2 TAILRACE TAILWATER eee neo 8 CONTROL WEIR EL 18 = | Q = : i pene | GEN. FLR. Oo EL. 23.0 6 H EQUIPMENT LEGEND 4330 kVA J 1 VATE 1 CONTROL AND RELAY PANEL 2 SWITCHGEAR AND STATION SERVICE POWER CENTER ae ; 3 MOTOR CONTROL CENTER Moriroe nocd 4 BATTERY BANK AND CHARGER PLAN 5 HYDRAULIC PRESSURE UNIT 6 SUMP PUMP 0 16 32 SCALE IN FEET KETCHIKAN PUBLIC UTILITIES WHITMAN LAKE HYDROELECTRIC PROJECT FERC PROJECT NO. 11597 POWERHOUSE PLAN AND SECTION FIGURE 1-5 WESCORP SECTION 2 Basin Hydrology SECTION 2 BASIN HYDROLOGY INTRODUCTION In order to estimate average annual energy from the proposed hydroelectric project, long-term streamflow records are required. Unfortunately, there does not exist any published streamflow records above the mouth of Whitman Creek. Therefore, synthesized monthly streamflow records were developed for the area above Whitman Dam based on correlation of recorded streamflow from an adjacent basin. METHODOLOGY Inflow to Whitman Lake was synthesized based on correlation of actual USGS published monthly records on Beaver Falls Creek during the period October 1920 through December 1925, and October 1927 through September 1932. Based on precipitation records at Ketchikan, this period was within 1 percent of the long term average annual precipitation. Therefore, the selected period of record can be considered representative of a long-term average. The Beaver Falls Creek gage was located about 4 miles north of Whitman Dam and measured streamflow from a 5.8 square mile drainage area. Annual streamflow averages 18.8 cfs per square mile. Beaver Falls Creek is the next major drainage north of Whitman Creek, and is the most appropriate gage for synthesizing Whitman Creek records because of the close proximity of the two basins, and the terrain, average basin elevation, basin size, percentage of lake surface, and geographic orientation are all very similar. In order to develop a continuous 12 year record of monthly flows, synthetic monthly streamflows for the Beaver Falls Creek gage were developed for the period January 1926 to September 1927. Monthly flows for the period January 1926 through August 1926 were developed based on regression analysis of monthly precipitation at Ketchikan and 10 years of monthly streamflow records at the Beaver Falls Creek gage. Correlating precipitation and streamflow can sometimes render poor results, particularly where measurement of snowfall and snowmelt skew the figures. But there are no other historical streamflow or precipitation records in the immediate Ketchikan area during the period in question. Fortunately, based on regression analysis of each month, the correlation coefficients varied within an acceptable range of 0.64 to 0.92 for every month. The resulting regression equations were therefore used to predict monthly streamflow at the Beaver Falls Creek gage for the period January 1926 through August 1926 based on the monthly precipitation at Ketchikan. Whitman Lake Hydroelectric Project 2-1 Feasibility Study August 1998 A separate regression analysis was performed for the months of September 1926 through September 1927. For this period, monthly streamflow records on Mahoney Creek were available. The Mahoney Creek basin is the next major basin north of the Beaver Falls Creek basin, and is also similar in character to the Whitman Creek basin. The Mahoney Creek gage measured streamflow from a 5.7 square mile drainage area. Annual streamflow averages 18.3 cfs per square mile. Based on regression analysis, the correlation coefficients for each month, except June, were all above 0.90 indicating a strong correlation exists. The June coefficient was still an acceptable 0.68. The resulting regression equations were then applied to develop monthly streamflows at the Beaver Falls Creek gage for the missing period of record. INFLOW TO WHITMAN LAKE The similarities of the Whitman Creek and Beaver Falls Creek basins are very strong. For example, the weighted average elevation of each basin is the same, 1,600 feet, and the terrain and geographic orientation with respect to mountain ridges are also nearly identical. For these reasons the average monthly streamflow in the Whitman Creek basin was estimated based on the ratio of the drainage areas, or 0.71 times the monthly streamflow at the Beaver Falls Creek gage. Table 2-1 presents estimated inflow to Whitman Lake for the period October 1920 to September 1932. These flows were used in the energy generation analysis and adjusted to account for the estimated distribution of daily peak flows in a given month. Whitman Lake Hydroelectric Project 2-2 Feasibility Study August 1998 6st 68! e6r e92 V6e 981 vel eet 0°92 e92 eer Ex! bE Let ws7s}9 | vLL SLL ore ezor leett |roaz oss ZZ S901 |e6o' |Zvs bp sor ‘(lets “Bay “OW 108 lek 2b 86 6It OF v9 6e $9 9 zoel 8°66 ZZL 6e i] beh eZ 9 29 SZ 91 ZL 9b 69 sor 16h 69 08 18h Z91 8S} GZ 8h ss 1eL cr) 8S Se €S 8 Os6t 8°99 SOL ge 1ST Zél i Zth ZL 68 69 ee 6e Ol se 6261 9°69 ZLL 82 r8 601 Ip 9b 9 08 6It 8b 26 Sb 61h 8z6l 69 Ve9 9€ ee 6hh €6 29 08 Ol 26 9b iy tz 6e Ze6t Vee Zel eZ v9 Zit 6h Sb 08 16 ézt 6p 29 6p gZ 9261 Z19 vel 9Zt zer s9 2 €s zor zor git 0s ze rm te Sz6h 768 zZ8 1S eal Ll bbl iy 68 26 gst 9b 6e v8 2s peel 86Z £08 98 |Szt eZ Z8 2s 2p oor Gal 101 cg 2s Zk €z6h 18 PSL Ov ct zel vel 9b g9 6el or 1S SI on gt z26h eeZ S06 sel 06 9Zt 80! OZ v8 1st 06 ee 62 +6 €@ 1261 fll ce S POL 0261 rewoL | (eioL d N O $ Vv c cr W Vv W 4 cr TeOX AM __ | 4epue|ea [ GNOOSS Had 1434 OIGND NI MOTINI SOVESAV i SV NVWLIHM OL MOTANI TVHNLYN ATHLNOW G3ZISSHLNAS be eqeL SECTION 3 Energy Generation Analysis SECTION 3 ENERGY GENERATION ANALYSIS PLANT OPERATION ASSUMPTIONS The project configuration and operation for this study was developed based on maximizing average annual energy generation at the least cost. In order to achieve this goal it was further assumed that operating the plant with reservoir level sensors will minimize spill past the dam and that plant operation will have priority over all other KPU-owned generating resources. For example, if all reservoirs in KPU’s system are full and system load is low, then Whitman Lake Project generation will be fully utilized at the expense of spilling at one of KPU’s other hydro projects. In accordance with the Four-Dam Pool Agreement, KPU is required to purchase power from the Swan Lake Project before using power from any of its own generating resources. This requirement should have no impact on the ability to maximize energy generation at the Whitman Lake Project because even in very wet years coupled with low system demand the Swan Lake Project could deliver only about 70 percent of the system energy requirements. In average years Swan Lake serves about 50 percent of the load. METHODOLOGY Average annual energy generation from the project was estimated based on a 12-year simulation of plant operation for water years 1920 through 1932. Reasons for selecting this time period are discussed in Section 2. A custom spreadsheet program was developed specifically for the Whitman Lake Project and results are presented in Table 3-1. : The program performs calculations based on a multitude of user-supplied input variables. Fixed program values include reservoir storage-elevation data and monthly inflow. The program user selects the number of units, turbine efficiency as a function of discharge, generator efficiency, length and diameter of the penstock, penstock friction factor, reservoir elevation operating range, a monthly reservoir rule curve, average tailwater elevation, monthly instream flow release, monthly releases for hatchery water supply, and a percentage of monthly inflow designated as “excess flow above turbine capacity”. The monthly excess flow values were developed to reduce the monthly inflow values by a factor that accounts for periodic high inflows that are in excess of the maximum turbine hydraulic capacity. The program places that portion of the excess flow volume that can be stored into storage then spills the remaining volume. One of the key variables that affects annual energy generation is the reservoir rule curve, or “target end-of-month (EOM) reservoir elevation”. The target elevations Whitman Lake Hydroelectric Project 3-1 Feasibility Study August 1998 TABLE 3-1 KPU HYDROELECTRIC FEASIBILITY STUDY ANNUAL ENERGY GENERATION ANALYSIS Whitman Lake Project - Preferred Alternative ANALYSIS SUMMARY: Physical and Operating Statistics: Target EOM Reservoir El. AVERAGE ANNUAL GENERATION = 19,641 MWH Unit 1 Rated Capacity = 3900 kW Jan UNIT 1 GENERATION = 13,900 MWH Unit 2 Rated Capacity = 700 kW Feb UNIT 2 GENERATION = 5,741 MWH Unit 1 Design Discharge = 150 cfs "Mar AVERAGE SPILL = 5.3 cfs Unit 2 Design Discharge = 30 cfs Apr AVG. EOM RES. EL. = 374.0 ft Penstock Diameter = 45 inches May AVG. NET HEAD, UNIT 1 = 347.0 ft Penstock Length = 2220 feet ~ Jun AVG. NET HEAD, UNIT 2 = 306.9 ‘Spillway Crest El. = 380 | Jul |AVG. ANNUAL PLANT FACTOR = 0.49 Minimum Oper. Res. El. = 362 Aug Unit 1 Tailwater El. = 20 Spt Unit 2 Tailwater El. = 40 _ Oct Hatchery Flow = 27 cfs Nov Dec Hatchery Excess Hatchery flow Instream Flow Average Unit 2 Unit 1 Total Total Calculated | Storage | Average | Flow from| withdrawn] Flow in Above Available Monthly | Average | Average Monthly Annual Calculated EOM surplus or Turbine Turbine 1 Turbine 2 Spillway Net Net Unit 1 Unit 2 Delivered | Delivered EOM Storage Flow, Discharge, Discharge, | Discharge} Head, Head, | Generation | Generation | Generation | Generation Res. El. cfs cfs cfs cfs feet feet MWH MWH MWH MWH 159] 129 298.0 | 3278 | 2,326 475 2,724 18,661 Whitman Lake Hydroelectric Project Hatchery Excess Hatchery flow Instream| Flow Average | Unit 2 Unit 1 Total Total Available Monthly | Average | Average Monthly Annual Turbine Turbine 1 Turbine 2 | Spillway Net Net Unit 1 Unit 2 Delivered | Delivered Flow, Generation | Generation cfs MWH 20,823 a) _ 0 0 30) wt 30) 20,455 30} 22,053 Page 2 of 5 Whitman Lake Hydroelectric Project Hatchery Excess Hatchery flow instream} Flow Average | Unit 2 | Unit 1 Total Total Calculated | Storage | Average] Flow from] withdrawn] Flow in | Above | Available Monthly | Average | Average Monthly } Annual Calculated Excess Turbine Spillway Unit 1 Unit 2 Delivered | Delivered EOM of Spill, Discharge Generation | Generation | Generation | Generation Res. El. cfs MWH 222 _| 17,557 20,621 17,692 Page 3 of 5 Whitman Lake Hydroelectric Project Hatchery Excess Hatchery} flow | instream} Flow Average | Unit 2 | Unit 1 Total Total Calculated | Storage | Average| Flow from| withdrawn] Flow in | Above | Available Monthly | Average | Average Monthly | Annual Target | Calculated] Target EOM | surplus or | Monthly | Whitman] from | Excess | Turbine | Turbine Turbine 1 | Turbine2 | Spillway | Net Net |} Unit 1 Unit 2. | Delivered | Delivered Eom | EOM EOM Storage | shortage | Inflow, | inflow | storage | of Spill, | Capacity,} Flow, Discharge, | Discharge, | Discharge] Head, | Head, | Generation} Generation| Generation | Generation Res. El MWH 17.871 16,968 17,481 Page 4 of 5 Whitman Lake Hydroelectric Project Hatchery Excess Hatchery flow Instream| Flow Average | Unit 2 Unit 1 Total Total Calculated | Storage | Average] Flow from| withdrawn] Flow in | Above | Avai Monthly | Average | Average Monthly | Annual Target | Calculated} Target EOM surplus or | Monthly | Whitman from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Net Unit 1 Unit 2 Delivered | Delivered EOM EOM EOM Storage shortage Inflow, inflow ‘storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge} Head, Head, | Generation} Generation | Generation | Generation Month | Year | Res. El. | Res. El. Storage af at cfs cts cfs cfs cfs cfs cfs cfs cfs feet feet MWH MWH MWH MWH Oct | 1930] 368 | 3677 5435 5388 966 204.2 27.0 00 00 547 178 148 30] 113 | 2965 | 3206 | 2645 489 3,048 Nov | 1930] 378 381.1 6846 7300 71458 216.2 27.0 00 00) 33.5 168} 150 30] 4.4 306.7 | 3302 | 2,634 489 _3,037 Dec | 1930] 380 395.5 7140 9560 160 2346) 27.0) 00) 0.0 15.2 220} 150 30} 179 | 3206 | 3441 | 2,836 528 3,272 Jan | 1931] 379 | 3788 6993 | 6969 2567 136.2 oo] oo 39 135 105 _ 30} 433 | 3194 | 3553 | 2,102 | 527 2,556 Feb | 1931 378 377.7 6846 6805 123 89.1 00) 24 47) 88} 58 30 16 310.5 354.6 907 462 1,332 Mar | 1931| 379 | 3787 6993 6955 -187 59.4 00} 40 06 53 23 30] 00 | 3105 | 3576 | 402 512 888 Apr_| 1931] 377 376.8 6701 6674 254 100.3 00 07; 64 101 71 30] 33 3100 | 3523 | 1,289 495 1,734 May | 1931| 375 | 3746 | oat2 6357 261 150.0 oo} oof — 187 151 121 30] 44 3080 | 3399 | 2,338 508 2.767 Jun | 1931 378 3778 6846 6809 489 96.6 0.0} 40) 96 85) 55] 30) 00 | 3085 352.9 918 492 1,371 Jul | 1931 369 368.9 5572 5559 1237 _ 86.7 0.0 34 6.0) 103 73 30) 06 305.6 347.6 1,351 504 1,804 Aug | 1931] 371 | 3709 5848 5838 -290 84.5 oo 40 12.9} 76 46 30] 00 | 3022 | 3476 | 781 498 1,244 Spt_| 1931 361 360.6 4510 4455 1328 948 00) 40) 157 114 84) 30) 0.0 298.0 338.1 1,494 475 }__ 1,915 24,969 Oct | 1931] 368 | 3678 5435 5402 980 156.4 27.0 oo} = 40} at. 137, 107| 30} 00 296.5 | 331.9 | 2,001 489 2,421 Nov | 1931] 378 | 3777 | 6846 6807 “1444 966] 27.0 oo} 40] 150] 39 30] 0.0 305.0 | 351.1 647 487 1,103 Dec | 1931] 380 379.7 7140 7090 -333 506 27.0 00 40) 33 42 _12| 30], 0.0 311.0 | 3585 210 513 | 703 Jan | 1932] 379 3787 6993 | 6954 97 828) 27.0 00 24] 24) 81 51 30} 16 311.5 | 3564 888 513 1,363 Feb | 1932| 378 377.8 6846 _ 6823 108 83.7 27.0 00) 28 44 82 52 30} 12 310.5 | 355.3 844 479 1,287 Mar | 1932] 379 378.9 6993, 6983 -169 50.6 27.0) 00} 40 05] 44 14 30} 00 | 3106 | 3581 245 512 736 Apr | 1932] 377 377.0 6701 6695 282, 83.2 27.0 00 13 53] 84] 54 30} 27 310.2 | 3548 906 495 1,362 May | 1932 375 3747 6412 6363 283 142.6 27.0) 00 01 44 My 144 114! 30) 39 308.1 341.8 2,208 508 2,641 Jun | 1932] 378 | 3778 6846 6818 483 153.6 27.0 0.0 18 15.2 142, 112 30] 22 308.5 | 3427 | 2,105 492 2,526 Jul_| 1932] 369 3687 | 5572 5524 1246 127.0 27.0 00 os} 8a] 144 114 30] 35 305.5 | 3392 | 2,191 504 2,621 Aug | 1932] 371 3706 5848 5798 324 615 27.0 00 40] a7] 53] 23 30] 0.0 301.9 | 3491 | 392 498 865 Spt_| 1932 361 360.6 4510 4454 1288 156.4) 27.0 0.0) 06) 26.0) 175) 145 30) 34 297.9 322.9 2,526 475 2,919 20,547 Page 5 of 5 Average Annual Energy (MW) 26,000 25,000 24,000 23,000 22,000 21,000 20,000 19,000 18,000 17,000 16,000 15,000 14,000 20 Figure 3-1 Annual Energy Probability Curve Preferred Alternative 30 40 50 60 70 80 90 100 Probability of Annual Generation Exceeding Y-axis Value Whitman Lake Hydroelectric Project shown in Table 3-1 are the optimum monthly values that result in the highest average annual generation. Other target elevations can be input to estimate average firm capacity in any given month or to maximize the amount of energy that can be generated over a select series of months. The minimum operating elevation will be set at El. 362, which is 18 feet below the spillway crest. Both the shallow and deep water intakes currently serving the hatchery should be unaffected by the hydro operation. The deep water intake should remain submerged at El. 362, and no unfavorable vortices should develop at the shallow intake. The more critical design element may be the hydraulics of the intake serving the new 45-inch penstock. AVERAGE ANNUAL ENERGY The project will generate an average of 19,641 MWh annually, including station service requirements and estimated transmission losses. The lowest annual energy generated during the 12-year simulation period was 16,968 MWh, which is 86 percent of average. The highest single year generated 24,969 MWh, or 27 percent above the average. The range of annual energy generation values indicates that annual project output will be relatively consistent from one year to the next. A summary of average monthly energy generation is shown in Table 3-2. Table 3-2 Lake Whitman Hydroelectric Project Average Monthly Energy Generation, MWh Jan Feb Mar Apr May — Jun Jul Aug Spt Oct Nov Dec Annual 1,205 944 846 1,131 2,542 2,190 2,030 1,062 1,905 2,328 1,910 1,548 19,641 The annual amount of energy generated from a hydroelectric project is dependent on the amount of annual precipitation that falls in the project drainage basin. Wet years result in above average amounts of generation and dry years result in lower than average expectations. In order to get a feel for the degree of variance in annual generation from the Whitman Lake Project, a probability curve was developed based on the 12 year period of analysis. An Annual Energy Probability Curve for the project was developed and is shown on Fig. 3-1. The curve was developed from a relatively small data base, but provides a good indication of the variance in generation that can be expected from year to year. PLANT FACTOR Based on an installed plant capacity of 4.6 MW, the project will operate at a 49 percent plant factor. By comparison, the Swan Lake Project operates at about a 37 percent plant factor. Lower capacity generating units were evaluated, but provided no distinct economic advantage over the recommended size units. For example, budget quotations obtained from turbine vendors showed virtually no difference in costs for units in the 3.0 to 4.0 MW range. Civil costs will also be about the same. Given the Whitman Lake Hydroelectric Project 3-2 Feasibility Study August 1998 ability to regulate up to 2,500 acre-feet of storage in Whitman Lake, the larger capacity generating unit will provide KPU better value and a little more flexibility in the future to shave peak loads. COMPARISON WITH EXISTING GENERATION RESOURCES Table 3-3 is a comparison of Whitman Lake Project generation and plant capacity to other hydro plants in the KPU system during calendar years 1992 through 1996. Table 3-3 Comparison with KPU Hydroelectric Resources Average Annual Estimated Avg. Generation, 1992-96} Annual Energy | Plant Capacity Resource MWh MWh MW Plant Factor Ketchikan Lakes 17,884 - 4.2 49 Silvis 10,383 - el 56 Beaver Falls 37,548 - 5.6 tale Swan Lake 72,032 - 22.5 .37 Whitman Lake - 19,641 4.6 49 Whitman Lake Hydroelectric Project 3-3 Feasibility Study August 1998 SECTION 4 Project Cost Estimate SECTION 4 PROJECT COST ESTIMATE DIRECT CONSTRUCTION AND INVESTMENT COSTS An estimate of construction and associated development costs was prepared for the Preferred Project based on experience data and vendor budget quotes for major equipment and materials. Based on engineering analysis and a January 1998 bid price level, the Direct Construction Cost is estimated to be $6,349,000. The Total Investment Cost, including engineering, construction contingency, interest during construction and escalation to a 2002 bid date, is estimated to be $8,786,000. The Direct Construction Cost is the estimated bid price a qualified contractor would submit today in a competitive construction market after fully understanding the specific job conditions and requirements. The Total Investment Cost is the total project development cost prior to adding in costs associated with selling bonds. Detailed construction cost estimates are presented in Tables 4-1 and 4-2. BASIS OF COST ESTIMATE The cost estimates prepared for the Preferred Alternative and the other project alternatives described in Appendix A were prepared based on a combination of vendor quotes and experience data for hydroelectric projects constructed in Alaska. Turbine and generator costs were determined based on review of budget quotations from five reputable turbine vendors. After sorting out the basis of each vendor's response, it was found that the spread between quotations was generally within 10 percent. Copies of turbine vendor responses are presented in Appendix C. Vendor quotes for steel pipe, the synchronous bypass valve and the steel-framed powerhouse superstructure were also obtained. Contingencies of 10 percent on turbine and generator equipment and 20 percent on all other items were included in the estimate. The lower contingency for the generating equipment reflects greater certainty that vendors understand the scope of the equipment contract. A 20 percent contingency for all other items reflects the degree of uncertainty in estimating final design quantities, subsurface conditions and other project design criteria that will become more clear in later stages of development. The Total Investment Cost was escalated at 3 percent annually from January 1998 to April 2002 to account for inflation over that period. KPU / SSRAA AGREEMENT The Preferred Project arrangement and associated construction cost estimates were prepared assuming the project would be integrated with the existing hatchery facilities Whitman Lake Hydroelectric Project 4-1 Feasibility Study August 1998 so as not to significantly impair current or future operation of the Herring Cove Fish Hatchery. However, it should be noted that a “Water and Land Use Agreement” signed in 1978 by SSRAA and KPU would require SSRAA to bear all costs to accommodate KPU. Section 10 of the Agreement states in part that “...Southern Southeast Regional Aquaculture Association, Inc., shall inform Ketchikan Public Utilities in writing, of the reasonable time necessary for SSRAA to proceed with due diligence to remove its facilities and operations from the site, or to modify its facilities to be compatible with those plans for construction as proposed by Ketchikan Public Utilities.” Other sections of the Agreement require SSRAA to subordinate its interests in leasehold agreements, rights of way and water rights in favor of KPU for the purpose of constructing and operating a hydroelectric power generating facility at Herring Cove. The estimated direct construction cost of the project can be reduced and average annual energy increased if terms of the Agreement are enforced. The “Least Cost” project alternative described in Appendix A is based on KPU exercising its full rights under the Agreement. Whitman Lake Hydroelectric Project 4-2 Feasibility Study y August 1998 Table 4-1 WHITMAN LAKE HYDROELECTRIC PROJECT CONSTRUCTION COST ESTIMATE PREFERRED ALTERNATIVE FERC FERC ACCT. ACCT NO. DESCRIPTION QUANTITY TOTAL 330 Land and Land Rights USFS Special Use Permit, Lot Easements LS $25,000 Total Acct. 330 $25,000 331 Structures and Improvements Care of Water LS $20,000 Clearing and Grubbing LS $8,000 Excavation Powerhouse 2100} CY 40 $84,000 Tailrace 350) CY 25 $8,750 Backfill 600} CY 18 $10,800 Gravel Surfacing 60 CY 20 $1,200 Landscaping and Revegetation LS $3,000 Riprap 200} CY 75 $15,000 Concrete Substructure 750 CY 450 $337,500 Tailrace 120 CY 450 $54,000 Insulated Metal Building Superstructure 2800 SF 65 $182,000 Miscellaneous Metals LS $25,000 Grounding Grid and Connections LS $8,000 Fire Protection Ls $12,000 Drainage System Ls $8,000 Office Equipment LS $10,000 Hatchery Improvements Modify Distribution Piping LS $150,000 Valve Automation for Temp. Control LS $45,000 Water Chemistry Controls LS $75,000 Construction Surveying - General Cont. LS $40,000 Mob/Demob - General Contract LS $300,000 Total Acct. 331 $1,397,250 Continued next page Whitman Lake Hydroelectric Project Feasibility Study Page 1 of 3 August 1998 Table 4-1 (continued) Preferred Alternative FERC ACCT NO. Reservoirs, Dams and Waterways DESCRIPTION QUANTITY FERC ACCT. TOTAL Care of Water Ls $15,000 Clearing and Grubbing LS $40,000 Dredging and Removal of Timber Crib Dam LS $60,000 Structural Improvements to Existing Dam LS $125,000 Excavation Shallow/Common Excavation 900} CY 20/}$ 18,000 Rock Excavation (buried pipe section) 680 CY 50}$ 34,000 Backfill Select Fill 270} CY 22/$ 5,940 Random Fill (from trench excavation) 300 CY 12) $ 3,600 45-inch Diameter Steel Pipe Bare Pipe 3/16" wall thickness 1700 LF 73) $ 124,100 1/4" wall thickness 320 Ce 86]}$ 27,520 5/16" wall thickness 200 LF 100}$ 20,000 24-inch Diameter Stee! Pipe 1050 LF 45|$ 47,250 Pipe Shipping 1 LS 65,000} $ 65,000 Pipe Installation LS $ 263,000 Concrete Pipe Supports 33 EA 3,500} $ 115,500 Concrete Pipe Anchors 16 EA 4,500}$ 72,000 Expansion Joints Ls $ 5,000 Additional Supports for 24" Pipe Ls $ 40,000 Pipe Connection to Existing Outlets LS $ 25,000 Trashrack LS $ 20,000 Diversion Facilities (two sites) Diversion and Care of Water Ls $ 10,000 Clearing and Grubbing LS $ 20,000 Excavation (at check dams) 100 CY 120}$ 12,000 Backfill (at check dams) 240 cY 40/$ 9,600 Concrete Check Dams 10] CY 1,500} $ 15,000 Pipe supports/anchors 35 cY 1,500} $ 52,500 Gates/Miscellaneous Metal Ls $ 9,000 16" Dia. HDPE Pipe 1760 LF 18}$ 31,680 24" Dia. HDPE Pipe 1600} LF 30|}$ 48,000 Pipe Installation LS $ 119,520 Revegetation LS $ 10,000 Total Acct. 332 $1,463,210 333 Turbines and Generators 3900 kW Turbine/Generator Unit LS $ 770,000 700 kW Turbine/Generator Unit LS $ 340,000 Generator Cooling System Ls $ 60,000 42" Turbine Inlet Butterfly Valve Ls $ 26,000 18" Turbine Inlet Butterfly Valve Ls $ 12,000 18" Synchronous Bypass Valve, Piping LS $ 80,000 Equipment Installation LS $ 70,000 Units Testing and Startup LS $ 15,000 Construction Surveying - Equip. Cont. LS $ 14,000 Mob/Demob - Equipment Contract LS $ 161,000 Total Acct. 333 |$ 1,548,000 334 Accessory Electrical Equipment Control and Protection System LS $ 320,000 4.16 kV Metal-Clad Switchgear LS $ 85,000 Station Service Power System LS $ 90,000 DC Power System LS $ 32,000 Cables, Conduits, Trays, Accessories LS $ 60,000 Reservoir Level Measurement System LS $ 30,000 Lighting Ls $ 18,000 Unit Heaters Ls $ 4,000 Total Acct. 334 | $ 639,000 Continued next page Whitman Lake Hydroelectric Project Feasibility Study Page 2 of 3 August 1998 Table 4-1 (continued) Preferred Alternative FERC FERC ACCT. ACCT NO. DESCRIPTION QUANTITY TOTAL Miscellaneous Power Plant Equipment 7.5 ton Hoist, Rails and Structural Supports LS $ 18,000 Ventilation Fans and Louvers LS $ 4,000 Sump Pump and Oil Separator LS $ 15,000 Total Acct. 335 | $ 37,000 336 Roads, Railroads and Bridges Gravel Surface Access Road 500 LF 16) $ 8,000 18" Culvert and Erosion Protection LS $ 3,000 Total Acct. 336 | $ 11,000 353 Switchyard Grading and Gravel Surfacing LS $ 3,000 Concrete Equipment Pads LS $ 6,000 Transformer, Circuit Breakers, Disconnects LS $ 280,000 Grounding Grid and Connections LS $ 15,000 Fencing, Gate LS $ 4,000 Lighting LS $ 8,000 _| Total Acct. 353 | $ 316,000 355 Poles and Fixtures LS $ 22,000 Total Acct. 355 | $ 22,000 356 Overhead Conductors and Devices LS $ 15,000 Total Acct. 356 | $ 15,000 DIRECT CONSTRUCTION COST $5,473,460 Whitman Lake Hydroelectric Project Feasibility Study Page 3 of 3 August 1998 Table 4-2 WHITMAN LAKE HYDROELECTRIC PROJECT Preferred Alternative PROJECT COST ESTIMATE SUMMARY FERC TOTAL ACCT DESCRIPTION COST COSTS 330 Land and Land Rights $25,000 331 Structures and Improvements $1,397,000 332 Reservoirs, Dams and Waterways $1,463,000 333 Turbines and Generators $1,548,000 334 Accessory Electrical Equipment $639,000 335 Miscellaneous Power Plant Equipment $37,000 336 Roads, Railroads and Bridges $11,000 353. Switchyard $316,000 355 Poles and Fixtures $22,000 356 Overhead Conductors and Devices $15,000 Direct Construction Cost $5,473,000 Contingency (Accounts 333,334), 10% $219,000 Contingency (All other Accounts), 20% $657,000 Direct Construction Cost Plus Contingencies $6,349,000 Owner Administration $100,000 Engineering and Licensing: FERC Licensing and Other Permits $210,000 Final Design and Field Studies $450,000 Construction Management $230,000 Total Construction Cost $7,339,000 Interest During Construction (6%/yr) $410,000 Total Investment Cost (bid Jan 98, on-line Spt 99) $7,749,000 Escalation to Proposed Bid Date (3.0%/yr) $1,037,000 Total Investment Cost (bid Apr 02, on-line Dec 03) $8,786,000 Total Investment Cost per Installed kW $1,910 Whitman Lake Hydroelectric Project Feasibility Study August 1998 SECTION 5 Cost of Energy Analysis SECTION 5 COST OF ENERGY ANALYSIS FIRST YEAR COST OF ENERGY The first year cost of energy was estimated, and results are presented in Table 5-1. The Total Capital Requirements (bond issue size), and first year annual cost were determined assuming KPU would issue 20 year bonds at 6 percent annual interest. For the Preferred Alternative arrangement, Total Capital Requirements are estimated to be $9,964,000, and the first year annual cost is $1,006,000 based on selling bonds and beginning construction in April 2002. The annual cost includes debt service, earnings on reserves, operation and maintenance, administration and general expenses, FERC compliance expenses, plant interim replacements and insurance. Based on an average annual delivered energy of 19,641,000 kWh, the first year cost of energy is 5.1 cents per kWh. This is significantly below the present cost of diesel generation. SENSITIVITY ANALYSIS The recommended project alternative was analyzed assuming an annual bond interest rate of 7 percent (versus 6 percent), and increasing the annual inflation rate from 3 percent to 4 percent. These higher values are reasonable considering the bond sale and construction contract awards would not occur for about another 3 years. When these assumptions are made Total Capital Requirements increase 6 percent to $10,558,000 and the first year cost of energy increases to 5.7 cents per kWh. Whitman Lake Hydroelectric Project 5-1 Feasibility Study August 1998 Table 5-1 WHITMAN LAKE HYDROELECTRIC PROJECT PREFERRED ALTERNATIVE ESTIMATED CAPITAL AND ANNUAL COSTS CAPITAL COSTS Total Investment Cost Financing Expenses Bond Reserve Working Capital Reserve TOTAL CAPITAL REQUIREMENTS ANNUAL COSTS Fixed Costs Debt Service Less Earnings on Reserves Total Fixed Costs Variable Costs Operation and Maintenance Administrative and General Expenses FERC Compliance Interim Replacements Insurance Total Variable Costs TOTAL ANNUAL COSTS (First Year) $8,786,000 $249,000 $869,000 $60,000 $869,000 $56,000 $120,000 $25,000 $8,000 $25,000 $15,000 FIRST YEAR COST OF ENERGY (cents/kWh) Assumptions: Annual Interest Rate on Bonds 6% Bond Term 20 years Reinvestment Rate 6% Financing Expenses 2.5 % of TCR Bond Reserve 1 year of debt service Working Capital Reserve 6 months of O&M costs Average Annual Energy 19,641 MWH Whitman Lake Hydroelectric Project Feasibility Study $9,964,000 $813,000 $193,000 $1,006,000 5.1 August 1998 SECTION 6 Project Development Schedule SECTION 6 PROJECT DEVELOPMENT SCHEDULE Project development will occur in three major phases; licensing, final design/contract documents, and construction. A schedule to complete all phases of development is shown on Fig. 6-1. The project will need to be licensed with FERC prior to beginning construction. Based on our knowledge of the issues that would need to be addressed in a License Application for the Whitman Lake Hydroelectric Project, we estimate it would take until May 2000 to file the license application with FERC. Once the license application is filed with FERC it has typically taken them between 12 and 20 months to process an Application of this type and issue the license. The elements of project construction should be divided into three major contracts; a Turbine/Generator supply contract, penstock supply contract and general construction contract. The Turbine/Generator contract will need to be sent out for bid as early as possible after the FERC license is issued because of the long lead times required for fabrication. Preparation of the Turbine/Generator supply contract will take about 3 months to prepare, and contract documents for all three construction contracts will take between 8 and 10 months to complete. Construction contracts will be executed over an approximate 18 month period depending on time of year the contracts are awarded. Based on these time frames, the project can be placed into service by December 2003. Whitman Lake Hydroelectric Project 6-1 Feasibility Study August 1998 FIGURE 6-1 WHITMAN LAKE HYDROELECTRIC PROJECT PROJECT DEVELOPMENT SCHEDULE 1998 1999 2000 2001 2002 2003 ACTIVITY JEMAMJJASONDIJFMAMJJASOND|IJFMAMJJASONDIJFMAMJJASONDIJFMAMJJASOND|JFMAMJJASOND _ pt ft _- ttt} tft} itp | hehe {14 14 |FERC LICENSING FERC 6-mo. Reports __ FERC Preliminary Permit Expires | License Application Preparation - "License Application Processing FINAL DESIGN _Turbine/Generator P&S Penstock Supply P&S ~ General Construction P&S CONSTRUCTION | Turbine/Generator Supp Penstock Supply . _ General Construction | | 2 tit pt ttt ‘Unit Testing and Startup _ Plant On-Line SECTION 7 Environmental and Regulatory Issues SECTION 7 ENVIRONMENTAL AND REGULATORY ISSUES INTRODUCTION This section presents the preliminary environmental and regulatory issues that would likely need to be addressed in order to develop the project. It is typical for this type of project to encounter other issues not yet identified at this time, but will be brought to KPU’s attention during the FERC license preparation process. Unless otherwise noted, the issues discussed herein relate to the Preferred Project Alternative. WATER QUALITY AND QUANTITY Existing Information Whitman Lake is the water supply for the Southern Southeast Regional Aquaculture Association (SSRAA) Herring Cove hatchery and is monitored for water quality. Water from Whitman Lake was described as cold, clear and clean by Jay Creasy, hatchery manager (SSRAA, pers. comm. 1997). SSRAA collects water quality data from a station 80 feet deep. Table 7-1 provides ranges of some of their data: Table 7-1 Water Quality Data for Whitman Lake (Source: SSRAA, pers. Comm. 1997). STATION TEMP DISSOLVED |DISSOLVED PH OXYGEN OXYGEN (°C) (mg/l) (% saturation) Lake Whitman 80 feetdepth [45-65 |9.1- 10.1 80 -90 5.9 -6.1 The quantity of precipitation combined with steep slopes and shallow soils allow surface water to drain quickly into the lakes and reduces the time for water to concentrate dissolved ions and minerals (Dames and Moore, 1990). Though the existing information does not include chemical analysis of the water samples, it is likely that chemical conditions of these lakes are consistent with federal and state water quality standards. Currently, SSRAA has a water right for 39 cfs for their Herring Cove salmon hatchery. The Herring Bay Water Users Association has a water right for 100,000 gpd (.15 cfs). A permit was granted to the Herring Bay Water Users Association from the U.S. Forest Whitman Lake Hydroelectric Project 7-1 Feasibility Study August 1998 Service on February 17, 1971 for the diversion and water system. Currently, KPU does not have a water right for appropriations from this system. Median monthly flows (50% exceedence) in Whitman Creek range from a low of 19.2 cfs in August to a high of 88 cfs in October. Water supply available for diversion in the low flow summer months may be greatly reduced or not available. Water Quality/Quantity Issues and Agency Concerns Water issues that have been identified by Alaska Department of Fish and Game (ADFG) and by SSRAA are temperature, gas saturation and water quantity. These concerns can be managed with project design features and monitoring of water quality. The proposed Whitman Lake Project will not likely have long-term impact on water quality of the lake or bypass reaches. Project construction may cause short-term impacts such as increased turbidity and suspended solids. An erosion and sediment control plan will need to be developed and strict adherence to best-management practices (BMPs) will need to be followed to avoid excessive impacts to the waterbodies during the construction phase. The lake tap alternative presents issues concerning potential impacts of water withdrawal from the mid-depth of Whitman Lake and impacts to downstream water users. Withdrawing water from mid-depth may impact the natural stratification of Whitman Lake which may have an effect on the lake’s ecosystem. Also, a group of homes in Herring Cove utilize Whitman Creek for their domestic water supply. Drawing the lake below the original lake outlet would eliminate the ability to release water downstream until the lake level rises above the natural outlet. Additional Studies A request from USEPA is on record (USEPA, 1997) for baseline water quality studies to include physical, chemical and biological characteristics of all water bodies and tributaries which would be impacted by the project and by-pass reaches. These studies would include temperature, pH, gas saturation, dissolved solids, alkalinity, acidity, chemical analysis for heavy metals, ammonia, nitrates, sulfates, and carbonate. In addition to these studies, macroinvertebrate analysis will give a baseline indication of the biological health of the water systems and will be useful to the fisheries and wildlife portions of these studies. Although the agencies have not specifically requested macroinvertebrate analysis, it has increasingly become a focus of aquatic studies during licensing and relicensing procedures. The agencies may request macroinvertebrate studies during formal consultation. Water quality studies should be conducted in July or August when water temperature will be at a maximum and dissolved oxygen might be at a minimum. This period would give a “worse case” situation and would compare to historical data collected by ADFG. Water quality investigations can be conducted in conjunction with fisheries and wildlife studies which will make field work more efficient and cost effective. Whitman Lake Hydroelectric Project 7-2 Feasibility Study August 1998 Water quality certification will need be obtained from the Alaska Department of Environmental Conservation (ADEC) as part of the permitting process. Water rights will also need to be obtained from Alaska Department of Natural Resources (ADNR). Potential Mitigation/Enhancement Measures An erosion and sediment control plan will need to be developed and strict adherence to best-management practices (BMPs) will need to be followed to avoid excessive impacts to the waterbodies during the construction phase. FISHERIES Existing Information Anadromous fish have access to Whitman Creek only as far as the South Tongass Highway bridge. There is a waterfall which acts as a total anadromous barrier at this point. ADFG believes there may be intertidal spawning at the mouth of Whitman Creek. No site-specific studies of resident fisheries resources in Whitman Lake and Whitman Creek were found to exist. Jay Creasy of SSRAA stated that there are Dolly Varden in Whitman Lake, and that below the dam, there are a few Dolly Varden. Fisheries Issues and Agency Concerns ADFG believes there may be intertidal spawning at the mouth of Whitman Creek, and that it will be necessary to provide adequate flows for this spawning activity. Due to the lack of knowledge of existing resident fish resources in the bypass reach, ADFG would need surveys to identify the fisheries resources of the creek. Once these resources are known, flows would need to be provided for these fish. Another concern expressed by the agencies was the potential of spawners in Whitman Lake tributaries. Lake fluctuations caused by the project could either deny access to these tributaries or dewater redds. The location and timing of fish spawning in these tributaries would need to be studied and identified. The timing of fry emergence would also need to be determined. Instream Flow Requirements Surveys will need to be conducted to determine the status of resident fish present in Whitman Creek, and their distribution and abundance if present. If resident salmonids are present, an instream flow study may be required by the agencies to indicate appropriate flows. Due to a significant amount of runoff entering Whitman Creek downstream of the dam, appropriate instream flows would not be comprised totally of releases from the lake. Whitman Lake Hydroelectric Project 7-3 Feasibility Study August 1998 If surveys indicate an absence of resident salmonids in the bypass reach of Whitman Creek, the resource agencies will not allow a total diversion of flow (i.e., dewatering), but instream flow releases from Whitman Lake would be minimal. For the purpose of this study it was assumed that a constant 4 cfs would be released from storage to supplement runoff from the area downstream of Whitman Dam. Additional Studies Several studies would need to be conducted by KPU before instream flows can be negotiated for the project: e Fish and physical stream survey of Whitman Creek from Whitman Lake downstream to saltwater to determine species composition, distribution, and abundance of resident fish, if present, and a description of the physical habitat of Whitman Creek. e Spawner surveys of Whitman Creek tributaries to identify spawning locations and to determine spawning and emergence timing of resident trout. e An instream flow study may be needed in Whitman Creek if the agencies determine that a significant resource is present downstream of Whitman Lake. Costs for fish surveys of Whitman Creek would be minimal, requiring a two-person crew two days or less to electroshock Whitman Creek and quantify the habitat. Costs to survey Whitman Lake could be minimized by contracting with a local resident familiar with Dolly Varden to conduct the surveys Results of the fisheries investigations described above will be instrumental in determining whether an instream flow study would be required for Whitman Creek. Potential Mitigation/Enhancement Measures Minimum instream flows in Whitman Creek will be required by the agencies. The quantity of instream flow required will depend on if a significant resident fish population is found downstream of Whitman Lake. It does not appear that ADFG would require screening of the intake or outflow from the penstocks, based upon previous comments to the Beaver Falls and Mahoney Lakes projects. BOTANICAL RESOURCES Existing Information Botanical resources within the project area include a variety of mixed aged conifer forests ranging from mature and old growth stands, with dense canopies and open subcanopy layers, to younger generation tree plantations. Native species of conifer trees found in the area include; Sitka spruce (Picea sitkensis), western hemlock Whitman Lake Hydroelectric Project 7-4 Feasibility Study August 1998 (Tsuga heterphylla), western red cedar (Thuja plicata) and yellow cedar (charmaecyparis nootkatensis). The western hemlock-Sitka spruce forest system extends from sea level to treeline. Other conifer species found in lower densities include: Alaska cedar, mountain hemlock, alpine fir, pacific fir and lodgepole pine. Deciduous trees species includes red alder, sitka alder, and cottonwood. These forest typically have very dense canopy and understory layers. Species comprising the understory vegetation include; huckleberry, blueberry, devils club, copper bush, juniper, skunk cabbage, ferns, mosses, grasses and sedges. Intermediate plant communities that combine elements of forest and bog habitat grow near the forest edge and along the shorelines of Whitman Lake. Wetland delineation maps do not distinguish between the acidic peat-moss (spagnum spp.) bogs and the emergent vegetation wetlands, the latter of which generally supports greater wildlife diversity and richness than the former habitat type. Bogs are also expected to be the more plentiful wetland type found near the project area. Botanical Resources Issues and Agency Concerns Some vegetation will likely be lost to due to construction activities associated with building the powerhouse, pipeline and access road. Revegetation of disturbed areas will occur as soon as construction activities are completed. Threatened, endangered or sensitive plant species could potentially be a concern. Table 7-2 details sensitive plants known or suspected to occur within the project area. Additional Studies Sensitive plant surveys would need to be conducted in locations where development, construction, or environmental changes are expected to occur. This includes construction of roads and pipeline, inundation of shoreline and riparian areas, and clearing of right-of-ways. The location of sensitive plants found within the project area will be mapped, photographed and data submitted to the Alaska Natural Heritage Program. Potential Mitigation/Enhancement Measures The majority of sensitive plant species listed above are found in wet, moist habitats such as wetlands, bogs, riparian areas and shorelines. In many cases these areas can be avoided when planning roads, trails, and access routes for the project, particularly since these areas also contain high wildlife values. However, in cases where the project development route cannot avoid a sensitive area, steps will need to be taken to minimize impacts to that area and on-site mitigation or near-site mitigation will need to be provided. Whitman Lake Hydroelectric Project 7-5 Feasibility Study August 1998 Table 7-2 Sensitive Plants Known or Suspected to Occur within the Project Area (Source: Alaska Natural Heritage Program, 1997 and USFS, pers. comm. 1997a) Choris bog orchid (Plantanthera chorisiana) Circumpolar strwort (Stellaria ruscifolia ssp. aleutica) Bog orchid (Platanthera gracilis) Calder lovage (/igusticum calderi) Goose-grass sedge (Carex lenticularis var. dolia) Pale poppy (papaver alboroseum) Edible thistle (Cirsium edule) Loose-flowered bluegrass (Poa laxiflora) Davy mannagrass (Glyceria leptostachya) Northern bog clubmoss (Lycopodium inundatum) Two-flowered marsh marigold (Caltha biflora) Watershield (Brasenia schreberi) Douglas spiraea (Spiraea douglasii) Poverty oat-grass (Danthonia spicata) Straight-beak buttercup (Ranunculus orthorhynchus var. alaschensis) Western paper birch (Betula papyrifera var commutata) Water lobelia (Lobelia dortmanna) Cassiope lycopodioides Small cranberry (Vaccinium oxycoccos) Prairie lupine (Lupinus lepidus) Northern bugleweed (Lycopus uniflorus) Mexican hedge-nettle (Stachys mexicana) Kamchatka spike-rush (Eleocharis kamtschatica) Water bulrush (Scirpus subterminalis) False solomon’s-seal (Smilacina racermosa) Bog bluegrass (Poa leptocoma) Asplenium viride Alaska holly fern (Polystichum setigerum) Boreal bedstraw (Galium kamtschticum) Lewis monkeyflower (Mimulus lewisii) Sxifraga occidentalis Cascade beardtongue (Penstemon serrulatus) Subalpin fir (Abies lasiocarpa) Pacific yew (Taxus brevifolia) Wright filmy fern (Hymenophyllum wrightii) Black hawthorn (Crateagus douglasii var douglasii) WILDLIFE RESOURCES Existing Information Wildlife habitat in the vicinity of the project area can be divided into seven broad categories: alpine, subalpine, estuary, riparian forest, upland forest, open water, and wetland. The alpine category encompasses lands above the timberline, including cliff and talus slopes. The subalpine category includes forested and scrub covered areas, with some unvegetated terrain lying between the alpine zone and the upland forest. The upland forest includes all forested and non-forested habitat below the subalpine zone and outside of riparian and wetland areas. Open water habitat includes all lakes, rivers, streams, and coastal waters. Riparian and wetland habitats include those lands adjacent to streams, lakes, and estuaries that support plant and animal species requiring more mesic habitat conditions. Estuaries are comprised of all lands lying within the zone of tidal influence. Whitman Lake Hydroelectric Project 7-6 Feasibility Study August 1998 Very little wildlife information exists specific to the project area. As such the following species information is more general. In cases where specific information exists for the project area, the species, location and source for the reference is provided. Endangered and Threatened Wildlife There are no endangered or threatened wildlife species known to occur in the vicinity of the project (USFWS 1997; USFS, pers. comm. 1997a; ADFG, pers. comm. 1997). Birds: Peregrine Falcon (Falco peregrinus pealei) is the only listed species with the potential to occur in the vicinity of the project. This species may occur as a transient in Southeast Alaska, primarily during seasonal migration. No critical habitat has been designed for this species and there have been no historical records of peregrine falcons in the project area. Preliminary review of photographs and topographic maps did not reveal suitable nesting habitat (cliff eyries) and relatively low usage of waterfowl in the project area indicates that there may not be much of a prey base to support peregrine falcons. Bald Eagle (Haliaeetus leucocephalus): Although the bald eagle is not a threatened or endangered species in Alaska, it is protected by the state and therefore surveys will likely be requested by the various state and federal agencies in the area. The marbled murrelet (Branchyramphus mamrmoratus) and the Northern goshawk (Accipiter gentilis laingi) are both species of special interest to the USFS and the USFWS due to their association with old growth and mature conifer forest habitats. It is assumed that marbled murrelets and northern goshawks are nesting in the vicinity of the project area (ADFG, pers, comm. 1997; USFS, pers. comm. 1997a). One known nest site has been documented for Northern Goshawk on the west side of Herring Bay near Whitman Lake. Raptor and marbled murrelet surveys may need to be conducted in order to document the presence or absence of these birds within the project area. Harlequin Duck (Histrionicus histrionicus) was also mentioned as a species of special interest and might warrant surveys due to its close association with open water and riparian habitats (ADFG, pers, comm. 1997) Surveys for this species can be combined with stream habitat inventories. Mammals: The Alexander Archipelago wolf (Canis /upus ligoni) is a high profile species known and/or suspected to occur in the vicinity of the project (ADFG, pers, comm. 1997). Whitman Lake is expected to contain a relatively large number of wolves with the highest usage, as compared to the Connell Lake area Whitman Lake Hydroelectric Project 7-7 Feasibility Study August 1998 (moderate usage) and the Carlanna Lake area (low usage). Sitka black-tailed deer is the primary food source for wolves which might also explain the high rating for Whitman Lake (high carrying capacity for deer). Therefore, studies of wolf populations and range are good indicators of the overall deer population and habitat sustainability. The USFS and USFWS have both identified the Alexander wolf as a possible species for federal listing, which also makes surveying for this species important. Revillagigedo Island red-backed vole (Clethrionomys gapperi solus) is a subspecies of the red-backed vole and is only found on Revillagigedo Island. There is a mapped record for this vole in Ketchikan (Natural Heritage Database, 1997) and therefore may occur within the project area. These voles appear to prefer mesic areas in coniferous, deciduous and mixed forests with dense cover and abundant litter, stumps, rotting logs, exposed roots, and a dense leaf litter. Habitat availability does not appear to be a limiting factor for this species and there was no mention of declining population status in the literature. Therefore surveys for red-backed vole may not be warranted in the project area. Opportunistic sightings and areas with good habitat suitability could be documented in conjunction with other studies. Although Ketchikan is not classified as a subsistence community, many residents rely on hunting in the surrounding Tongass to provide food for their families. Sitka black-tailed deer and black bear are two primary game species with importance to local residents of Ketchikan. Habitat mapping and field reconnaissance surveys would be useful for identifying baseline conditions and providing an analysis tool for managing deer and bear habitat within the project area (ADFG pers. comm. 1997). Amphibians: Spotted Frog is a species of special interest to the agencies (USFWS, ADFG, USFS). Opportunistic searches and dip-netting of selected areas will identify presence of the species and project related effects. Wildlife Resources Issues and Agency Concerns Potential impacts associated with the Whitman Lake Project include: increased road and trail access which may impact local deer hunting and rearing, landscape clearing which may result in a direct loss of habitat for some wildlife species, and fluctuating water levels which may cause inundation or dewatering of nesting and denning habitats. The USFWS area biologist has also identified Whitman lake as an area with high usage for the Alexander Archipelago wolf (Canis lupus ligoni) a potential species for federal listing (ADFG, pers. comm. 1997). The agencies will also be concerned about the project’s transmission line and their impacts on birds. Powerline designs that minimize the chance of bird collision and/or electrocution should be developed using current state of the art practices (Avian Powerline Interaction Committee, 1992). Whitman Lake Hydroelectric Project 7-8 Feasibility Study August 1998 The status of threatened and endangered species is a concern for the natural resource agencies and most likely will need to be addressed during the licensing phase. Additional Studies For project licensing, wildlife and habitat field studies would likely include the following: e Qualitative surveys of wildlife habitats and plant communities e Inventory of individual plant and animal species, including threatened and endangered ° Obtaining information on topography and historical land use ° Special habitats (wetlands, old growth forests, etc..) will be located, mapped and described ° Ancillary observation (including identification of calls, tracks, scat, and raptor pellet analysis). Specific studies and analysis for animal species will need to be determined through consultation with the agencies. Potential Mitigation/Enhancement Measures Protecting high wildlife use areas such as emergent vegetation wetlands, riparian corridors and old growth forests will help maintain good biodiversity and species richness within the project area. New transmission line construction should be built using state of the art practices to avoid and minimize avian collisions with powerlines as well as providing nesting platforms, territorial boundaries, and hunting perches for raptors. Proper design of roads, pipelines and other project facilities can also reduce the amount of habitat fragmentation which could occur. Gating new and existing roads coupled with seasonal access restrictions may help prevent over hunting and protect rearing habitats for deer, bear, mountain goat, waterfowl, and other game species. Currently waterfowl habitat appear to be limited within the project area due to a lack of forage and refuge cover at certain times of the year. Nevertheless, the project may be a good candidate for enhancement efforts to improve waterfowl production around the reservoir. These efforts may include increasing water depths in certain areas for diving ducks, reducing water elevations in other areas to allow for more emergent vegetation growth along shorelines, create island habitats to reduce predation and provide cover, and constructing nest boxes and platforms to promote nesting. Another effective strategy for improving wildlife resources is instituting an effective monitoring program to evaluate changes (both positive and negative) in the environment. Establishing photopoint monitoring stations and Habitat Suitability Index (HSI) sites are two proven methods for documenting baseline (pre-project) habitat conditions and assessing the effectiveness of management prescriptions and enhancement efforts within the project area. In-kind mitigation plans can also be developed for individual species following a more precise assessment of project related impacts. Whitman Lake Hydroelectric Project 7-9 Feasibility Study August 1998 LAND USE AND OWNERSHIP Existing Information Land Use in the Whitman Lake Project area generally consists of dispersed recreation and fish rearing. Some locals are known to hike on an unimproved trail to Whitman Lake to fish, hunt and sight-see. A hatchery occupies the intertidal area off of Powerhouse Road. The hatchery leases Mental Health Trust lands from the Alaska Department of Natural Resources (ADNR). The proposed powerhouse sites and the lower portion of the pipeline would be located on these lands. The upper portion of the existing pipeline route is on lands owned by the State of Alaska. The upper portion of the tunnel route in the lake tap alternative is located on lands owned by the U.S. Forest Service, Tongass National Forest (USFS). Whitman Lake is within the boundaries of the USFS. The USFS has designated lands around Whitman Lake as Old-Growth Habitat. The primary goal of the Old-Growth Habitat land use designation is to “maintain old-growth forests in a natural or near-natural condition for wildlife and fish habitat”(USFS, 1997b). To the extent feasible, roads, facilities and permitted uses are to be limited to those compatible with Old-Growth Habitat management objectives. New road construction is generally inconsistent with Old-Growth Habitat land use designation objectives, but new roads may be constructed if no feasible alternative is available. The proposed project facilities are located on Future Development Zone lands as designated by the Ketchikan Gateway Borough. Under this designation, hydroelectric generation is considered a permitted use. The Whitman Lake area has been designated as an environmentally sensitive area in the Ketchikan District Coastal Management Program (Ketchikan Gateway Borough, 1983). According to the Environmentally Sensitive Areas Map, the Whitman Lake environmentally sensitive area is located near the outlet of Whitman Creek, along George Inlet. The Whitman Lake area is considered an environmentally sensitive area because the shoreline serves as critical winter range for deer, heavy sportfishing occurs along the shore, and potential avalanche or landslide area exists. Development is not precluded in environmentally sensitive areas. However, special consideration must be given to the identified concerns. No National Wild and Scenic Rivers Systems, National Trails Systems or Wilderness Areas are located within the Whitman Lake Project area. Land Use Issues and Agency Concerns No major concerns regarding land use are anticipated. Construction activities for the pipeline and powerhouse may temporarily disrupt hatchery operations and trail users. Whitman Lake Hydroelectric Project 7-10 Feasibility Study August 1998 Additional Studies No significant land use studies are expected as part of project licensing. Only an update of the information presented in this section would be expected. A Special Use Permit would be required from the USFS. Potential Mitigation/Enhancement Measures No mitigation or enhancement measures are expected. RECREATIONAL RESOURCES Existing Information Activities such as hiking, fishing, boating, hunting, camping, and picnicking are popular among residents and tourists of Ketchikan. The USFS Tongass National Forest, which surrounds Ketchikan, has constructed many hiking trails and cabins for public use in southeast Alaska. No developed recreation facilities are located near the proposed Whitman Lake Project area. Mainly local residents hike an unimproved trail to Whitman Lake to fish and hunt. The hike is approximately one-half mile long and the use is low. Alaska Department of Fish and Game (ADFG) Sports Fishing Division and others have discussed improving the recreation access to Whitman Lake. The USFS Recreation Opportunity Spectrum (ROS) designation is Semi-Primitive Non- Motorized (SPNM) around Whitman Lake, and Rural at the lower end of Whitman Lake and in the areas where the pipeline alternatives would be located. Under the SPNM designation, alterations are few and subordinate to the landscape, trails and lakes are closed to motorized use, and human use is noticeable but not degrading to the resources elements. Under the Rural designation, alterations to landform and vegetation dominate the landscape, all methods of access and travel may occur, and there is moderate to high concentrations of people. (USFS, 1997b) Recreation Issues and Agency Concerns No significant impacts to recreation activities in the area are expected. Construction activities at the dam and for the pipeline and powerhouse may temporarily disrupt trail users for short periods of time. Additional Studies No significant recreation studies are expected to be required for project licensing. However, additional details on recreation use and demands in the area will likely be required for the License Application. Whitman Lake Hydroelectric Project 7-11 Feasibility Study August 1998 Potential Mitigation/Enhancement Measures Agencies may request trail improvements as part of the project. VISUAL RESOURCES Existing Information The project area consists of western hemlock-sitka forests that extend from the tidewater to the treeline. The forests extend to the edge of Whitman Lake. Whitman Creek is relatively steep with numerous cataracts, waterfalls and rapids. The creek is surrounded by dense forest. The existing dam structure and pipeline to the hatchery are visible from the air and by those who hike up to the lake. The lower portion of the pipeline can be seen extending down the hill to the hatchery. The tunnel portion of the lake tap alternative will not be visible. The penstock will be above ground and will require clearing in currently undisturbed areas. The powerhouse site will also require clearing. The USFS has assigned the Visual Quality Objective of Retention to the project area. Under the Retention designation, design activities should not be visually evident to the casual observer. Exceptions for small areas of non-conforming developments may be made on a case by case basis. Developments must use designs and materials that are compatible with forms, colors, and textures found in the characteristic landscape (USFS, 1997b). Visual Issues and Agency Concerns Clearing for the pipeline route and access road will produce visual impacts. Changes in the lake elevation will also have visual impacts. Reductions in flows into Whitman Creek would also have visual impacts. These impacts are expected to be minor since they would only be viewed from the air and from those who hike to the lake. The lower portion of the pipeline route and the powerhouse would be visible from the hatchery. Additional Studies No major visual resource studies are anticipated for the license application. Only minor updates to the information presented in this section are anticipated. Potential Mitigation/Enhancement Measures Revegetation following any clearing activities would be required to reduce any visual impacts resulting from construction of the project. Whitman Lake Hydroelectric Project 7-12 Feasibility Study August 1998 HISTORIC/CULTURAL RESOURCES Existing Information Little is recorded regarding the prehistoric period for southeast Alaska, although it is known that the Tlingit Indians for years had fish camps near the present City of Ketchikan and that they had a village at Ketchikan Creek. White settlements formed around canneries and mines in early Alaska. Ketchikan was founded near the salmon saltery at the mouth of Ketchikan Creek and canneries gradually relocated to Ketchikan because of its convenience for shipping. The State Historic Preservation Officer (SHPO) was contacted regarding reported historic and prehistoric sites within the project area. A review of the Alaska Heritage Resources Survey (AHRS) database and maps by the SHPO revealed one reported petroglyph site near the intertidal area at Herring Bay. It is not expected that construction and operation of the proposed project would impact this site. Additional sites that may have cultural significance in the project area that are not included on the AHRS database include an old cribbing dam that is submerged in Whitman Lake and remnants of the old wood stave pipeline. Cultural Resources Issues and Agency Concerns No cultural resources issues or agency concerns are anticipated unless additional eligible cultural resources sites are identified during field surveys. Additional Studies Routine cultural surveys will need to be performed as part of the license application process. Potential Mitigation/Enhancement Measures If cultural resources are identified during surveys, compliance under Section 106 of the National Historic Preservation Act would be required. The site’s eligibility under the National Register and the effects of activities on the property would need to be determined. If the property is found eligible, avoidance or mitigation measures would need to be developed in consultation with the State of Alaska Department of Natural Resources Office of History and Archaeology. If during construction, it is determined that the project will have an effect on a previously unidentified but eligible property, work will be suspended and the responsibilities under Section 106 of the National Historic Preservation Act would need to be followed. Whitman Lake Hydroelectric Project 7-13 Feasibility Study August 1998 FERC LICENSING ALTERNATIVES There are two strategies to licensing the Whitman Lake Hydroelectric Project; 1) the conventional approach, or 2) the Applicant Prepared Environmental Assessment (APEA) approach. The main difference in the two approaches is the entity preparing the environmental assessment pursuant to NEPA and related statutes. Under the conventional approach, the Federal Energy Regulatory Commission (FERC) performs the environmental review. With the APEA approach, the applicant (KPU) is responsible for preparing the environmental assessment. Under the APEA process, there is more intensive consultation with resource agencies, tribes and non- governmental organizations. The main advantage of the APEA approach is that agencies become more involved during preparation of the license application and NEPA document, which results in better certainty about what terms and conditions FERC will impose when it issues the license. For these reasons, it is recommended that KPU proceed with development in accordance with the APEA process. Whitman Lake Hydroelectric Project 7-14 Feasibility Study August 1998 SECTION 8 Conclusions and Recommendations SECTION 8 CONCLUSIONS AND RECOMMENDATIONS Based on the studies conducted for this feasibility report, the following conclusions can be made: As The Whitman Lake Hydroelectric Project is technically and economically feasible, and can be constructed without significant adverse environmental impacts. 2. The recommended project arrangement includes rehabilitation measures to existing Whitman Dam, constructing two diversion structures, a new 2,220-foot long steel penstock, a powerhouse containing two units totaling 4.6 MW of capacity, a switchyard and 1,200-foot long transmission line. 3. Design of the recommended project arrangement can be made compatible with the operating objectives of the Herring Cove hatchery and local water user's association. 4. The lake tap alternative, described in Appendix A is significantly less feasible than the Preferred Project arrangement. 5: The Preferred Project arrangement will generate 19,641,000 kWh on an average annual basis. This is about 15 percent of KPU’s 1996 load. 6. The Total Investment Cost for the project is $8,786,000 based on escalation to a year 2002 bid date. Ve First year cost of power is 5.1 cents per kWh. 8. The project can be placed into service by December 2003. Based on the findings and conclusions of this study, KPU should pursue development of the Whitman Lake Hydroelectric Project as described for the Preferred Alternative. Whitman Lake Hydroelectric Project 8-1 Feasibility Study August 1998 APPENDIX A Alternative Project Configurations APPENDIX A ALTERNATIVE PROJECT CONFIGURATIONS 1. Introduction In order to develop the optimum configuration of project facilities for the Whitman Lake Hydroelectric Project, several alternative configurations were evaluated for cost, energy generation, environmental impacts and ability to be integrated with the existing hatchery. In addition to the Preferred Alternative described in the main body of this report, three alternative configurations were studied. The alternatives are: Initial Surface Penstock Alternative — This is a variation to the Preferred Alternative that was initially evaluated. Lake Tap Alternative — This is an alternative that has been considered since first introduced in the 1950's. Least Cost Alternative — This alternative assumes KPU enforces its 1978 agreement with SSRAA to the full extent, which would disregard the water supply needs of the existing hatchery. The following is a description of these three alternative project configurations. 2. Initial Surface Penstock Alternative 2.1 Description This project alternative involves constructing a new 48” steel penstock from Whitman Dam to a powerhouse at Herring Cove containing two turbine/generator units totaling 5.3 MW. The penstock will follow the same general alignment as the existing hatchery water supply pipelines. Dimensions and sizes of principal project features are presented in Table A-1. The following is a description of facilities associated with this alternative. Existing Whitman Dam The existing dam would be utilized in the same manner described for the Preferred Alternative. The existing timber crib dam would also be removed. New Diversion Structures The two diversion structures described in the Preferred Alternative would be used to augment water supply to Whitman Lake. Whitman Lake Hydroelectric Project A-1 Feasibility Study Appendix A Table A-1 Project Statistics Initial Surface Penstock Alternative Drainage Area Natural Drainage Area Diversion Area (2 sites) Average Annual Natural Outflow at Dam Combined Average Annual Flow at Diversion Sites Reservoir Normal Maximum Operating Elevation Normal Minimum Operating Elevation Active Storage at El. 380 Surface Area at El. 380 Surface Area at El. 362 Existing Dam Dam Type Maximum Structural Height Crest Length Dam Crest Elevation Spillway Type Spillway Crest Elevation Spillway Width Outlets Penstock Penstock Diameter Penstock Length Powerhouse Type Size Unit 1: (Horizontal Francis) Rated Capacity Rated Head Maximum Discharge Unit 2: (Horizontal Francis) Rated Capacity Rated Head Maximum Discharge Transmission Line Voltage Length Whitman Lake Hydroelectric Project A-2 Feasibility Study 4.1 square miles 1.25 square miles 78 cfs 23 cfs 380 362 2,500 acre-feet 148 acres 129 acres Concrete Gravity Arch 46 feet 220 feet 385 Ogee Sill within Dam 380 40 feet 2-36” dia. And 1-42” dia. 48 inches 2,290 feet Steel-Frame Metal Building 3,000 square feet 3,900 kw 330 feet 150 cfs 1,400 kw 350 feet 53 cfs 34.5 kV 1,500 feet Appendix A New 48-inch Diameter Penstock A new 48-inch diameter, 2,290-foot long, steel penstock will be constructed from the dam to the powerhouse at Herring Cove. Water supply to the hatchery would be conveyed in the new penstock, and the existing supply lines would remain in operation principally as backup for water supply or temperature control. Intake Connection The existing temperature control system is designed to mix up to 27 cfs from the two existing outlets. Not enough is known about the existing design to know if it could be readily adapted to handle the 203 cfs maximum powerhouse flow, but for this feasibility study it was assumed that modifications will be necessary. Modifications would involve installing a new selective withdrawal system on the existing 36-inch outlet not currently being used by the hatchery and modifying the existing deep water intake piping at the dam. A new selective withdrawal system may be needed because the 42-inch outlet the current system is tied to is too high. Under conditions of high powerhouse flow and low reservoir level a strong vortex would form and draw unwanted air into the penstock. Using the lower 36-inch conduit can minimize this problem. A specially fabricated steel bifurcation will connect the two existing 36-inch conduits at the base of the dam to the new 48-inch diameter penstock. The right conduit (looking downstream) will still draw water from the deeper part of the lake, and the left conduit will be capable of drawing water from shallow depths, although the hydraulic capacity of this conduit will diminish at higher elevations. The existing valves will be used to control the proportion of flow to the penstock, but the turbine wicket gates will still control the rate of flow. The temperature control needs of the hatchery, and how they can be incorporated into the design of a new hydroelectric project, need to be analyzed further. Currently, it appears that the hydro project’s much greater demand for water will overwhelm the smaller capacity temperature control system now being used by the hatchery. Although the intake valves will be automated to instantaneously control the proportion of high and low temperature water, there will be operating constraints imposed on the selective withdrawal system that at times could impact either the hatchery’s temperature needs or the hydro plant’s ability to generate at the desired flow rate. Instream Flow Release Valve The method of making releases at the base of the dam is the same as described in the Preferred Alternative. Powerhouse A 3,000 square foot steel-framed powerhouse will be located near the existing hatchery about 150 feet north of the furthest western raceway. The Whitman Lake Hydroelectric Project A-3 Feasibility Study Appendix A powerhouse will contain a 3.9 MW unit and a 1.4 MW unit for a total installed capacity of 5.3 MW. The larger unit will operate within a flow range between 50 and 150 cfs, and the small unit will operate between 22 and 53 cfs. Both turbines will be horizontal Francis type machines, which are the most appropriate type unit with the given head and flow conditions. In order to suppress the magnitude of hydraulic transient pressures in the penstock when flow is abruptly changed, an 18-inch diameter synchronous bypass valve will be installed to automatically open if the turbine wicket gates suddenly close due to a line fault or other reasons. Tailwater level exiting the powerhouse will be controlled at about El. 40. This is about 20 feet higher in elevation than what would normally be selected if hatchery water demands were not a factor, but the layout allows hatchery flow requirements to be met without bypassing the turbines. A 24-inch pipe will connect the tailrace to the existing hatchery water distribution piping to convey up to 27 cfs. According to hatchery personnel the existing 14-inch diameter primary water distribution piping at the hatchery operates under a maximum pressure head of 70 psi (161 feet). This piping will need to be replaced with 24-inch diameter piping in order to convey the required hatchery flow under the lower pressure head. Switchyard and Transmission Line The plant switchyard will be located adjacent to the powerhouse and will contain a power transformer, circuit breakers and disconnect switches. A new 1,500 foot long 34.5 kV transmission line will be constructed from the switchyard to an intertie with the 34.5 kV Beaver Falls line along Tongass Highway. Plant Operation Plant operation will be the same as described for the Preferred alternative. 2.2 Estimated Energy Generation The Initial Surface Penstock Alternative will generate an average of 19,339 MWh annually. Based on an installed plant capacity of 5.3 MW, the project will operate at a 42 percent plant factor. Results of the energy generation analysis are presented in Table A-2. 2:3) Project Costs The Direct Construction Cost of this alternative, including contingencies, is estimated to be $6,183,000 based on a January 1998 bid price level. Total Capital Requirements are estimated to be $9,739,000. Detailed project costs are shown in Tables A-3 through A-5. First year cost of energy is 5.1 cents/kWh. Whitman Lake Hydroelectric Project A-4 Feasibility Study Appendix A TABLE A-2 KPU HYDROELECTRIC FEASIBILITY STUDY ANNUAL ENERGY GENERATION ANALYSIS Whitman Lake Project - Initial Surface Penstock Alternative ANALYSIS SUMMARY: Physical and Operating Statistics: Target EOM Reservoir El. AVERAGE ANNUAL GENERATION = 19,339 MWH Unit 1 Rated Capacity = 3900 kW UNIT 1 GENERATION = 16,133 MWH Unit 2 Rated Capacity = 1400 kW UNIT 2 GENERATION = 3,206 MWH Unit 1 Design Discharge = 150 cfs AVERAGE SPILL = 4.7 cfs Unit 2 Design Discharge = 53 cfs AVG. EOM RES. EL. = 373.4 ft Penstock Diameter = 48 inches May 375 AVG. NET HEAD = 324.4 ft Penstock Length = 2290 feet ae MES ZO AVG. ANNUAL PLANT FACTOR = 0.42 Spillway Crest El. = 380 Jul 369 Minimum Oper. Res. El. = 362 Ac unns 70 Average Tailwater El. = 40 _ Spt 362 Instream Flow = 4 cfs Oct 371 Hatchery Flow = 27 cfs Nov 378 Dec 378 Hatchery Excess Hatchery} flow Instream| Flow Average Total Total Calculated | Storage | Average] Flow from| withdrawn] Flow in | Above | Available Monthly | Average Monthly }| Annual Calculated] Target EOM surplus or | Monthly | Whitman | from | Excess | Turbine | Turbine Turbine 1 Turbine 2 | Spillway | Net Unit 1 Unit 2. | Delivered | Delivered EOM EOM Storage shortage Inflow, inflow storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge] Head, | Generation | Generation | Generation | Generation Res. El. | Storage af cfs feet MWH MWH MWH MWH 117 3172 | 2103 | 0 saa | o | esa 336.5 0 741 3369 | 0 18,443 Whitman Lake Hydroelectric Project Initial Surface Penstock Alternative Hatchery Excess flow Instream Flow Average Total Total Calculated Storage withdrawn | Flow in Above Available Monthly | Average Monthly Annual Target | Calculated} Target EOM surplus or from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Unit 1 Unit 2 Delivered | Delivered EOM EOM EOM Storage shortage storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge} Head, | Generation | Generation | Generation | Generation Res. El. cfs MWH 0.0) 0} 61.1 . 53 18.1] 7 ith O.7) 20,126 19,942 22,080 Page 2 of 5 Whitman Lake Hydroelectric Project Initial Surface Penstock Alternative Calculated EOM Storage Storage ‘surplus or shortage af Average Monthly Hatchery flow withdrawn from storage cfs Instream Flow in Excess of Spill, cfs Available Turbine Flow, Turbine 1 Discharge, cfs Turbine 2 Discharge, Average Monthly Spillway Discharge cfs Unit 1 Unit 2 Generation | Generation MWH Total Monthly Delivered Generation Total Annual Delivered Generation MWH —— oo 0.0) O41 13.2 00 0.0) 0.0) ae 00 00] 0.0) 9 ue] £0 146 ak Blolaoolo 47 25 2,519 16,738 00 0.0 0.0 0.0] | | | | | | colo 20,344 17,625 Page 3 of 5 Whitman Lake Hydroelectric Project Initial Surface Penstock Alternative Calculated EOM Storage Storage surplus or shortage at Hatchery flow withdrawn from Instream Flow in Excess of Spill, cfs Available Turbine Flow, Turbine 1 Discharge, | Discharge, Average Monthly Spillway Discharge Average Net Head, feet Unit 1 Generation MWH Unit 2 Generation Total Monthly Delivered Generation Total Annual Delivered Generation MWH 71234 3.7 4.0) 40) a0 2,312 17,566 17,141 16.0) 17,175 Page 4 of 5 Whitman Lake Hydroelectric Project Initial Surface Penstock Alternative Hatchery Excess Hatchery] flow | Instream| Flow Average Total Total Calculated Storage Average] Flow from] withdrawn} Flow in Above Available Monthly | Average Monthly Annual Target | Calculated} Target —OM ‘surplus or | Monthly | Whitman from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Unit 1 Unit 2 Delivered | Delivered EOM EOM EOM Storage | shortage | Inflow, inflow | storage | of Spill, | Capacity, Flow, Discharge, | Discharge, | Discharge] Head, | Generation] Generation | Generation | Generation af cfs feet MWH MWH 5818 g ; 547 2.471 8145 234, : 15.2 3.9 47 os] 24,697 Spt | 1932 | i 4] q - 20,190 Page 5 of 5 Table A-3 WHITMAN LAKE HYDROELECTRIC PROJECT CONSTRUCTION COST ESTIMATE INITIAL SURFACE PENSTOCK ALTERNATIVE FERC FERC ACCT. ACCT NO. DESCRIPTION QUANTITY TOTAL 330 Land and Land Rights USFS Special Use Permit, Lot Easement LS $25,000 Total Acct. 330 $25,000 331 Structures and Improvements Care of Water LS $20,000 Clearing and Grubbing LS $8,000 Excavation Powerhouse 1900 CY 40 $76,000 Tailrace 450} CY 25 $11,250 Backfill 600} CY 18 $10,800 Gravel Surfacing 60} CY 20 $1,200 Landscaping and Revegetation LS $3,000 Riprap 200 CY 75 $15,000 Concrete Substructure 350 CY 450 $157,500 Tailrace 150} CY 450 $67,500 Insulated Metal Building Superstructure 3000 SF 60 $180,000 Miscellaneous Metals LS $25,000 Grounding Grid and Connections LS $8,000 Fire Protection LS $12,000 Drainage System LS $8,000 Office Equipment LS $10,000 Hatchery Improvements Modify Distribution Piping LS $150,000 Valve Automation for Temp. Control LS $45,000 Water Chemistry Controls LS $75,000 Construction Surveying - General Cont. Ls $40,000 Mob/Demob - General Contract LS $300,000 Total Acct. 331 $1,223,250 Continued next page Whitman Lake Hydroelectric Project Feasibility Study Page 1 of 3 August 1998 Table A-3 (continued) Initial Surface Penstock Alternative FERC FERC ACCT. ACCT NO. DESCRIPTION QUANTITY TOTAL Reservoirs, Dams and Waterways Care of Water Ls $15,000 Clearing and Grubbing LS $40,000 Dredging and Removal of Timber Crib Dam LS $60,000 Structural Improvements to Existing Dam LS $125,000 Excavation Shallow/Common Excavation 850 CY 20} $ 17,000 Rock Excavation (buried pipe section) 600 CY 50] $ 30,000 Backfill Select Fill 230 CY 22|$ 5,060 Random Fill (from trench excavation) 280 CY 12) $ 3,360 48-inch Diameter Steel Pipe Bare Pipe 3/16" wall thickness 1600 LF 77| $ 123,200 1/4" wall thickness 400 LF 911 $ 36,400 5/16" wall thickness 290 LF 105} $ 30,450 Shipping i LS 45,000} $ 45,000 Installation LS $ 228,000 Concrete Pipe Supports 35 EA 3,500] $ 122,500 Concrete Pipe Anchors 18 EA 4,500} $ 81,000 Expansion Joints LS $ 5,000 Pipe Connection to Existing Outlets LS $ 25,000 Trashrack LS $ 20,000 Diversion Facilities (two sites) Diversion and Care of Water Ls $ 10,000 Clearing and Grubbing LS $ 20,000 Excavation (at check dams) 100 CY 120] $ 12,000 Backfill (at check dams) 240 CY 40) $ 9,600 Concrete Check Dams 10 CY 1,500} $ 15,000 Pipe supports/anchors 35 (e 1,500} $ 52,500 Gates/Miscellaneous Metal LS $ 9,000 16" Dia. HDPE Pipe 1760 LF 18} $ 31,680 24" Dia. HDPE Pipe 1600 LF 30) $ 48,000 Pipe Installation LS $ 119,520 Revegetation LS $ 10,000 Total Acct. 332 $1,349,270 333 Turbines and Generators 3900 kW Turbine/Generator Unit LS $ 770,000 1400 kW Turbine/Generator Unit LS $ 470,000 Generator Cooling System LS $ 60,000 42" Turbine Inlet Butterfly Valve LS $ 26,000 24" Turbine Inlet Butterfly Valve LS $ 18,000 18" Synchronous Bypass Valve, Piping LS $ 80,000 Equipment Installation LS $ 75,000 Units Testing and Startup LS $ 15,000 Construction Surveying - Equip. Cont. LS $ 14,000 Mob/Demob - Equipment Contract LS $ 175,000 Total Acct. 333 | $ 1,703,000 Continued next page Whitman Lake Hydroelectric Project Feasibility Study Page 2 of 3 August 1998 Table A-3 (continued) Initial Surface Penstock Alternative FERC FERC ACCT. ACCT NO. DESCRIPTION QUANTITY TOTAL Accessory Electrical Equipment Control and Protection System LS $ 320,000 4.16 kV Metal-Clad Switchgear LS $ 85,000 Station Service Power System LS $ 90,000 DC Power System LS $ 32,000 Cables, Conduits, Trays, Accessories LS $ 60,000 Reservoir Level Measurement System LS $ 30,000 Lighting LS $ 18,000 Unit Heaters LS $ 4,000 Total Acct. 334 | $ 639,000 335 Miscellaneous Power Plant Equipment 7.5 ton Hoist, Rails and Structural Supports LS $ 18,000 Ventilation Fans and Louvers Ls $ 4,000 Sump Pump and Oil Separator LS $ 15,000 Total Acct. 335 | $ 37,000 336 Roads, Railroads and Bridges Gravel Surface Access Road 750 LF 16} $ 12,000 18" Culvert and Erosion Protection LS $ 3,000 Total Acct. 336 | $ 15,000 353 Switchyard Grading and Gravel Surfacing Ls $ 3,000 Concrete Equipment Pads LS $ 6,000 Transformer, Circuit Breakers, Disconnects LS $ 280,000 Grounding Grid and Connections LS $ 15,000 Fencing, Gate LS $ 4,000 Lighting LS $ 8,000 Total Acct. 353 | $ 316,000 355 Poles and Fixtures LS $ 25,000 Total Acct. 355 | $ 25,000 356 Overhead Conductors and Devices LS $ 16,000 Total Acct. 356 | $ 16,000 DIRECT CONSTRUCTION COST $5,348,520 Whitman Lake Hydroelectric Project Feasibility Study Page 3 of 3 August 1998 Table A-4 WHITMAN LAKE HYDROELECTRIC PROJECT Initial Surface Penstock Alternative PROJECT COST ESTIMATE SUMMARY FERC TOTAL ACCT DESCRIPTION COST COSTS 330 Land and Land Rights $25,000 331 Structures and Improvements $1,223,000 332 Reservoirs, Dams and Waterways $1,349,000 333 Turbines and Generators $1,703,000 334 Accessory Electrical Equipment $639,000 335 Miscellaneous Power Plant Equipment $37,000 336 Roads, Railroads and Bridges $15,000 353 Switchyard $316,000 355 Poles and Fixtures $25,000 356 Overhead Conductors and Devices $16,000 Direct Construction Cost $5,348,000 Contingency (Accounts 333,334), 10% $234,000 Contingency (All other Accounts), 20% $601,000 Direct Construction Cost Plus Contingencies $6,183,000 Owner Administration $100,000 Engineering and Licensing: FERC Licensing and Other Permits $210,000 Final Design and Field Studies $450,000 Construction Management $230,000 Total Construction Cost $7,173,000 Interest During Construction (6%/yr) $400,000 Total Investment Cost (bid Jan 98, on-line Spt 99) $7,573,000 Escalation to Proposed Bid Date (3.0%/yr) $1,014,000 Total Investment Cost (bid Apr 02, on-line Dec 03) $8,587,000 Total Investment Cost per Installed kW $1,620 Whitman Lake Hydroelectric Project Feasibility Study August 1998 Table A-5 WHITMAN LAKE HYDROELECTRIC PROJECT Initial Surface Penstock Alternative ESTIMATED CAPITAL AND ANNUAL COSTS CAPITAL COSTS Total Investment Cost Financing Expenses Bond Reserve Working Capital Reserve TOTAL CAPITAL REQUIREMENTS ANNUAL COSTS Fixed Costs Debt Service Less Earnings on Reserves Total Fixed Costs Variable Costs Operation and Maintenance Administrative and General Expenses FERC Compliance Interim Replacements Insurance Total Variable Costs TOTAL ANNUAL COSTS (First Year) $8,587,000 $243,000 $849,000 $60,000 $849,000 $55,000 $120,000 $25,000 $8,000 $25,000 $15,000 FIRST YEAR COST OF ENERGY (cents/kWh) Assumptions: Annual Interest Rate on Bonds 6% Bond Term 20 years Reinvestment Rate 6% Financing Expenses 2.5 % of TCR Bond Reserve 1 year of debt service Working Capital Reserve 6 months of O&M costs Average Annual Energy 19,339 MWH Whitman Lake Hydroelectric Project Feasibility Study $9,739,000 $794,000 $193,000 $987,000 5.1 August 1998 3. Lake Tap Alternative 3.1 Description Constructing a lake tap can be an economic alternative for sites with deep natural lakes and competent rock for tunneling. Over 300 lake taps have been constructed in Norway where these prerequisite conditions are prevalent. The primary benefit to constructing a lake tap is it provides access to a large amount of storage without the cost of a dam, or raising an existing dam, to develop an equivalent amount of storage. Based on bathymetric survey mapping of Whitman Lake in September 1997, it was found that a lake tap can develop 7,100 acre-feet of active storage without increasing the height of the existing dam. The bathymetric map shows steep side slopes and a large flat bottom at depths between 120 and 140 feet. Project Statistics for the Lake Tap alternative are presented in Table A-6. Existing Whitman Dam and Reservoir Structural modifications to the existing dam, as discussed in the Preferred Alternative, will be needed. In addition, an 8-inch diameter throttling valve will be tapped onto the existing 24-inch diameter pipeline at the dam to provide a 4 cfs instream flow release when the reservoir level is above El. 362, the approximate natural outlet elevation of the lake. It will not be possible to make reservoir releases at the dam when the lake level is below El. 362. This presents problems for meeting the hatchery’s needs, supplying sufficient water to meet domestic needs at Herring Cove, and meeting fishery and aquatic culture needs within Whitman Creek below the dam. The hatchery will obtain its supply of water from the powerhouse tailrace, in much the same manner as described in the Preferred Alternative. However, the existing deep water intake and selective withdrawal system currently used by the hatchery for temperature and water chemistry control cannot be incorporated in a lake tap arrangement because the systems are too far away from the tunnel to be of any use and they would not be functional when the lake level falls below El. 362. Minimum operating level for this project alternative is El. 320. Therefore, a new selective withdrawal system would need to be constructed near the tunnel intake that would involve separate piping from the lake to the powerhouse via the tunnel. The drainage area below the dam may be sufficient to maintain water supply to the diversion intake operated by the Herring Cove Water User’s Association provided none of the streamflow is diverted to Whitman Lake as proposed in the Preferred Alternative. Based on discussions with the Association's representative, Dave Pflaum, they do not rely on regulated releases from Whitman Dam except during extreme cold periods. Freezing temperatures reduce the flow rate and makes the water uncomfortably cold for domestic use. During those periods the Association opens a 6-inch valve in the valve house at the base of the dam to provide a little warmer water and ensure sufficient supply to its members. If the lake tap arrangement is constructed, the Whitman Lake Hydroelectric Project A-5 Feasibility Study Appendix A Table A-6 Project Statistics Lake Tap Alternative Drainage Area Natural Drainage Area Diversion Area Average Annual Natural Outflow at Dam Average Annual Flow at Diversion Site Reservoir Normal Maximum Operating Elevation Normal Minimum Operating Elevation Active Storage at El. 380 Surface Area at El. 380 Surface Area at El. 320 Existing Dam Dam Type Maximum Structural Height Crest Length Dam Crest Elevation Spillway Type Spillway Crest Elevation Spillway Width Outlets Tunnel and Penstock Lake Tap Invert Elevation Tunnel Section Type Tunnel Length Penstock Diameter Penstock Length Powerhouse Type Size Unit 1 Rated Capacity Unit 1 Rated Head Unit 1 Maximum Discharge Unit 2 Rated Capacity Unit 2 Rated Head Unit 2 Maximum Discharge Transmission Line Voltage Length Whitman Lake Hydroelectric Project A-6 Feasibility Study 4.1 square miles 0.3 square miles 78 cfs 5 cfs 380 320 7,140 acre-feet 148 acres 96 acres Concrete Gravity Arch 46 feet 220 feet 385 Ogee Sill within Dam 380 40 feet 2-36” dia. and 1-42” dia. 295 8-foot horseshoe 1,800 feet 48 inches 700 feet Steel-Frame Metal Building 3,000 square feet 3,900 kW 330 feet 150 cfs 1,400 kw 350 feet 53 cfs 34.5 kV 1,500 feet Appendix A Association may periodically lose the ability to augment supply during extreme cold periods. Storage releases from the dam to meet fishery needs would not be possible when the reservoir is drawn down below El. 362. When this occurs, the drainage area below the dam would be the only source of runoff to the creek, which may be sufficient for much of the year, but may occasionally be a problem in July and August. New Diversion Structure The 0.3 square mile diversion area described in the Preferred Alternative will be included in the lake tap alternative. The larger diversion area included in the Preferred Alternative is not included in this alternative because diverting the stream would impact on water rights held by the Herring Cove Water User's Association, and on releasing minimum instream flows when the reservoir is drawn below El. 362. Lake Tap, Tunnel and Penstock Topographic and geologic conditions are good for constructing a lake tap. Based on bathymetric mapping, a good location for a lake tap would be on the south face of the lake approximately 1,000 feet upstream from the dam and at a depth of 85 feet. In order to gain access to the downstream portion of the lake tap a 1,800-foot long tunnel would be excavated from an entrance portal located about 900 feet northwest of the existing hatchery. The tunnel needs to be a minimum of 6 feet diameter to maintain acceptable head losses and maximum tunnel flow velocities. Although contractors would be given the flexibility, within guidelines, to select the most economical tunnel cross section size and shape, an 8-foot horseshoe shaped tunnel was assumed for this study because it is about the smallest size tunnel that can be excavated and still accessed with vehicles and other large equipment. As the tunnel advances toward the lake it can be expected that fractured areas, shear zones and other areas of weak rock may be encountered and require temporary or permanent structural support or lining. Grouting and rock bolting is anticipated. Based on observation of surface outcrops by R&M Engineering, Inc. (Appendix B), it is estimated that less than 10 percent of the tunnel will require concrete lining. A rock pit will be excavated in the floor of the tunnel large enough to capture rock from blasting the final plug. A few weeks prior to blasting the final plug the lake level will be lowered as far as possible, to about El. 362, by opening the existing 36-inch outlet at the dam. This will help to reduce hydrostatic pressures in the rock as the tunnel face gets closer to the lake. Whitman Lake Hydroelectric Project A-7 Feasibility Study Appendix A A concrete plug will be constructed at the downstream end of the tunnel and will encase a 48-inch diameter steel pipe, which will connect to a 48-inch above-ground steel penstock. The penstock will be 700 feet long, conveying flow to the powerhouse located near the existing hatchery. Powerhouse The powerhouse location, size and arrangement will be the same as described in the Initial Surface Penstock Alternative. The powerhouse will contain a 3.9 MW unit and a 1.4 MW unit with capability of discharging up to 203 cfs at full load. Switchyard and Transmission Line The plant switchyard will be located adjacent to the powerhouse and contain a power transformer, circuit breakers and disconnect switches. A new 1,500 foot long 34.5 kV transmission line will be constructed from the switchyard to an intertie with the 34.5 kV Beaver Falls line along Tongass Highway. 3.2 Estimated Energy Generation The Lake Tap Alternative will generate an average of 16,158 MWh annually. Based on an installed plant capacity of 5.3 MW, the project will operate at a 35 percent plant factor. A detailed reservoir operation and energy generation analysis is shown in Table A-7. The main reason why this project alternative generates less energy than the recommended project arrangement is because it does not include diverting streamflow from the 0.95 square mile drainage area north of Whitman Dam. As discussed in Paragraph 3.1, constructing the diversion as part of the lake tap arrangement would adversely impact current domestic water supply needs as well as minimum flows for fishery needs. Despite these difficulties, an average annual energy analysis was performed for the lake tap alternative assuming both diversion sites would be constructed and the resulting impacts could be mitigated. With both diversion sites contributing inflow to Whitman Lake average annual energy generation would be about 20,130 MWh. This is essentially the same energy output as the Preferred Alternative, but the marginal costs of the Lake Tap Alternative are significantly higher. An interesting conclusion about the lake tap analysis is that the additional reservoir storage does not result in any greater energy generation than the recommended project alternative. This occurs because there is lower average head with the lake tap and the use of reservoir level control significantly reduces the volume of spill. 3.3 Project Costs The Direct Construction Cost of this alternative, including contingencies, is estimated to be $8,096,000 based on a January 1998 bid price level. Total Capital Requirements are estimated to be $12,783,000. Detailed project costs are shown in Tables A-8 through A-10. First year cost of energy is 7.7 cents/kWh. Whitman Lake Hydroelectric Project A-8 Feasibility Study Appendix A TABLE A-7 KPU HYDROELECTRIC FEASIBILITY STUDY ANNUAL ENERGY GENERATION ANALYSIS Whitman Lake Project - Lake Tap Alternative Physical and Operating Statistics: ANALYSIS SUMMARY: Unit 1 Rated Capacity = 3900 kw Target EOM Unit 2 Rated Capacity = 1400 kW Reservoir El. AVERAGE ANNUAL GENERATION = 16,158 MWH Unit 1 Design Discharge = 150 cfs UNIT 1 GENERATION = 13,046 MWH Unit 2 Design Discharge = 53 cfs UNIT 2 GENERATION = 3,113 MWH Penstock Diameter = 48 inches AVERAGE SPILL = 1.8 cfs Penstock Length = 700 feet AVG. EOM RES. EL. = 359.8 ft Spillway Crest El. = 380 |AVG. NET HEAD = 317.8 ft Minimum Oper. Res. El. = 320 AVG. ANNUAL PLANT FACTOR = 0.35 Average Tailwater El. = 40 Instream Flow = 4 cfs Hatchery Flow = 27 cfs Tunnel Nom. Diameter = 8 feet Tunnel Length = 1800 feet Hatchery Excess Hatchery} flow | Instream| Flow Average Total Total Calculated | Storage | Average | Flow from] withdrawn] Flowin | Above | Available Monthly | Average Monthly }| Annual Target | Calculated} Target EOM surplus or | Monthly | Whitman | from | Excess | Turbine Turbine Turbine 1 Turbine 2 | Spilway | Net Unit 1 Unit 2 | Delivered | Delivered EOM EOM EOM Storage shortage Inflow, inflow storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge} Head, | Generation | Generation | Generation | Generation Month | Year | Res. El Res. El. Storage af af cfs cfs cfs cfs cfs cfs cfs cfs cfs feet MWH MWH MWH MWH Fee 835 15,026 Whitman Lake Hydroelectric Project Lake Tap Alternative Hatchery Excess Hatchery] flow | Instream| Flow Average Total Total Calculated Storage | Average | Flow from} withdrawn| Flow in Above Available Monthly Monthly Annual Target | Calculated} Target EOM ‘surplus or | Monthly | Whitman. from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Unit 1 Unit 2 Delivered | Delivered EOM EOM EOM Storage shortage Inflow, inflow storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge Generation | Generation | Generation | Generation af cfs MWH 5416 0.0) 15 5388 0.0 4601 17,185 16,620 18,645 Page 2 of 5 Whitman Lake Hydroelectric Project Lake Tap Alternative Hatchery Excess instream Flow Average Total Calculated Flow in | Above | Available Monthly | Average Annual Target | Calculated] Target EOM Excess Turbine 1 Turbine 2} Spilway | Net Unit 1 Unit 2 Delivered EOM EOM EOM Storage of Spill, Discharge, Generation af cfs cfs MWH 5414 0.0 119 5383 40 - 128 4595 et) 83 3500 0.0 ol 2023 00 o 2035 0.0 Oo} ___00 oO 0.0 106 9.0} _ - 15} 40 105 40 57 40 53 14,116 __ 0.0} o _ 4.0 138) 40 144 00} . 101 0.0) __79} _9.0 72 __0.0) ol oo 90 40) 2 __40 9 40 oO 17,225 0.0) nt04 409) 65) 40 87 . 00} 60 a) oO 00} oO 00] oO 00 =) 00 - _ 78 40) 81 __ 40 - 67 40 129] 14,304 Page 3 of 5 Whitman Lake Hydroelectric Project Lake Tap Alternative Hatchery Excess Hatchery flow Instream Flow Average Total Total Calculated Storage Average | Flow from| withdrawn| Flow in Above Available Monthly | Average Monthly Annual Calculated} Target EOM surplus or | Monthly | Whitman from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Unit 1 Unit 2 Delivered | Delivered EOM EOM Storage shortage Inflow, inflow storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge} Head, | Generation | Generation | Generation | Generation Res. El. Storage af cfs MWH MWH 367.9 542 5055 4615 0.0. 0.0 0.0 1,859 410 _ 52} oO |____—50) 0} 14,467 _ 0 oO | 37| 12 27 “al 0 0 o - 13,998 14,364 Page 4 of 5 Whitman Lake Hydroelectric Project Lake Tap Alternative Hatchery Excess Hatchery flow instream Flow Average Total Total Calculated Storage | Average | Flow from| withdrawn} Flow in Above Available Monthly | Average Monthly Annual Target | Calculated] Target EOM surplus or | Monthly | Whitman from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Unit 1 Unit 2 Delivered | Delivered EOM EOM EOM Storage | shortage | Inflow, | inflow | storage | of Spill, | Capacity, Flow, Discharge, | Discharge, | Discharge} Head, | Generation| Generation} Generation | Generation Res. El. cfs feet MWH MWH MWH 367.9 oo} 317.5 —o | 2531 40) 320.4 aS 21,003 16,946 Page 5 of 5 Table A-8 WHITMAN LAKE HYDROELECTRIC PROJECT CONSTRUCTION COST ESTIMATE LAKE TAP ALTERNATIVE FERC FERC ACCT. ACCT NO. DESCRIPTION QUANTITY TOTAL 330 Land and Land Rights USFS Special Use Permit LS $15,000 Lots 107, 108 and 112 Easements LS $12,000 Total Acct. 330 $27,000 331 Structures and Improvements Care of Water LS $20,000 Clearing and Grubbing LS $8,000 Excavation Powerhouse 1900 CY 40 $76,000 Tailrace | 450 cy 25 $11,250 Backfill | 600 CY 18 $10,800 Gravel Surfacing 60 CY 20 $1,200 Landscaping and Revegetation LS $3,000 Riprap 200 CY 75 $15,000 Concrete Substructure 350 cY 450 $157,500 Tailrace || 150 cY 450 $67,500 Insulated Metal Building Superstructure | 3000 SF 60 $180,000 Miscellaneous Metals LS $25,000 Grounding Grid and Connections LS $8,000 Fire Protection LS $12,000 Drainage System LS $8,000 Office Equipment LS $10,000 Hatchery Improvements Modify Distribution Piping LS $150,000 New Water Supply Line LS $90,000 Water Chemistry Controls LS $75,000 Construction Surveying - General Cont. LS $40,000 Mob/Demob - General Contract LS $300,000 I Total Acct. 331 $1,268,250 Continued next page Whitman Lake Hydroelectric Project Feasibility Study Page 1 of 3 August 1998 Table A-8 (continued) Lake Tap FERC ACCT NO. Reservoirs, Dams and Waterways DESCRIPTION QUANTITY FERC ACCT. TOTAL Care of Water Ls $40,000 Clearing and Grubbing LS $35,000 Structural Improvements to Existing Dam LS $125,000 Tunnel Excavation 3900 CY 250] $ 975,000 Tunnel Muck Disposal 5100 CY 15| $ 76,500 Concrete Lining 600 CY 1200} $ 720,000 Concrete Plug 45| CY 1200] $ 54,000 Rock Bolts 3500 LF 22| $ 77,000 Lake Tap LS $250,000 Tunnel Portal and Penstock Transition LS $65,000 Intake Vent LS $25,000 Penstock Excavation Shallow/Common Excavation 200 CY 20] $ 4,000 Rock Excavation 100} CY 50} $ 5,000 48-inch Diameter Steel Pipe Bare Pipe 1/4" wall thickness 300 LF 91) $ 27,300 5/16" wall thickness 400 LF 105} $ 42,000 Shipping LS $ 25,000 Installation LS $ 83,000 Concrete Pipe Supports 12 EA 3,500} $ 42,000 Concrete Pipe Anchors 5 EA 4,500} $ 22,500 Expansion Joints LS $ 2,500 Trashrack Ls $ 45,000 Diversion Facility Diversion and Care of Water LS $ 5,000 Clearing and Grubbing Ls $ 10,000 Excavation (at check dam) 50 CY 120] $ 6,000 Backfill (at check dam) 120 CY 40| $ 4,800 Concrete Check Dam 5 CY 1,500] $ 7,500 Pipe supports/anchors 18 CY 1,500] $ 27,000 Gates/Miscellaneous Metal LS $ 4,500 16" Dia. HDPE Pipe 1760 LF 18} $ 31,680 Pipe Installation LS $ 47,520 Revegetation LS $ 6,000 ae Total Acct. 332 $2,890,800 333 Turbines and Generators 3900 kW Turbine/Generator Unit LS $ 770,000 1400 kW Turbine/Generator Unit LS $ 470,000 Generator Cooling System LS $ 60,000 42" Turbine Inlet Butterfly Valve LS $ 26,000 24" Turbine Inlet Butterfly Valve LS $ 18,000 18" Synchronous Bypass Valve, Piping LS $ 80,000 Equipment Installation LS $ 75,000 Units Testing and Startup LS $ 15,000 Construction Surveying - Equip. Cont. LS $ 14,000 Mob/Demob - Equipment Contract LS $ 175,000 Total Acct. 333 | $ 1,703,000 Whitman Lake Hydroelectric Project Feasibility Study Page 2 of 3 Continued next page August 1998 Table A-8 (continued) Lake Tap FERC ACCT NO. DESCRIPTION Accessory Electrical Equipment QUANTITY FERC ACCT. TOTAL Control and Protection System LS $ 320,000 4.16 kV Metal-Clad Switchgear LS $ 85,000 Station Service Power System LS $ 90,000 DC Power System Ls $ 32,000 Cables, Conduits, Trays, Accessories LS $ 60,000 Reservoir Level Measurement System LS $ 35,000 Lighting LS $ 18,000 Unit Heaters LS $ 4,000 Total Acct. 334 | $ 644,000 335 Miscellaneous Power Plant Equipment 7.5 ton Hoist, Rails and Structural Supports LS $ 18,000 Ventilation Fans and Louvers LS $ 4,000 Sump Pump and Oil Separator LS $ 15,000 Total Acct. 335 | $ 37,000 336 Roads, Railroads and Bridges Gravel Surface Access Road 750 LF 16} $ 12,000 18" Culvert and Erosion Protection LS $ 3,000 Total Acct. 336 | $ 15,000 353 Switchyard Grading and Gravel Surfacing LS $ 3,000 Concrete Equipment Pads LS $ 6,000 Transformer, Circuit Breakers, Disconnects LS $ 280,000 Grounding Grid and Connections LS $ 15,000 Fencing, Gate LS $ 4,000 Lighting LS $ 8,000 Total Acct. 353 | $ 316,000 355 Poles and Fixtures LS $ 25,000 Total Acct. 355 | $ 25,000 356 Overhead Conductors and Devices LS $ 16,000 Total Acct. 356 | $ 16,000 Whitman Lake Hydroelectric Project Feasibility Study Page 3 of 3 Direct Construction Cost $6,942,050 August 1998 Table A-9 WHITMAN LAKE HYDROELECTRIC PROJECT Lake Tap Alternative PROJECT COST ESTIMATE SUMMARY FERC TOTAL ACCT DESCRIPTION COST COSTS 330 Land and Land Rights $27,000 331 Structures and Improvements $1,268,000 332 Reservoirs, Dams and Waterways $2,891,000 333 Turbines and Generators $1,703,000 334 Accessory Electrical Equipment $644,000 335 Miscellaneous Power Plant Equipment $37,000 336 Roads, Railroads and Bridges $15,000 353 Switchyard $316,000 355 Poles and Fixtures $25,000 356 Overhead Conductors and Devices $16,000 Direct Construction Cost $6,942,000 Contingency (Accounts 333,334), 10% $235,000 Contingency (All other Accounts), 20% $919,000 Direct Construction Cost Plus Contingencies $8,096,000 Owner Administration $100,000 Engineering and Licensing: FERC Licensing and Other Permits $375,000 Final Design and Field Studies $525,000 Construction Management $280,000 Total Construction Cost $9,376,000 Interest During Construction (6%/yr) $580,000 Total Investment Cost (bid Jan 98, on-line Nov 99) $9,956,000 Escalation to Proposed Bid Date (3.0%/yr) $1,333,000 Total Investment Cost (bid Apr 02, on-line Feb 04) $11,289,000 Total Investment Cost per Installed kW $2,130 Whitman Lake Hydroelectric Project Feasibility Study August 1998 Table A-10 WHITMAN LAKE HYDROELECTRIC PROJECT Lake Tap Alternative ESTIMATED CAPITAL AND ANNUAL COSTS CAPITAL COSTS Total Investment Cost Financing Expenses Bond Reserve Working Capital Reserve TOTAL CAPITAL REQUIREMENTS ANNUAL COSTS Fixed Costs Debt Service Less Earnings on Reserves Total Fixed Costs Variable Costs Operation and Maintenance Administrative and General Expenses FERC Compliance Interim Replacements Insurance Total Variable Costs TOTAL ANNUAL COSTS (First Year) $11,289,000 $320,000 $1,114,000 $60,000 $1,114,000 $70,000 $120,000 $25,000 $8,000 $25,000 $15,000 FIRST YEAR COST OF ENERGY (cents/kWh) Assumptions: Annual Interest Rate on Bonds 6% Bond Term 20 years Reinvestment Rate 6% Financing Expenses 2.5 % of TCR Bond Reserve 1 year of debt service Working Capital Reserve 6 months of O&M costs Average Annual Energy 16,158 MWH Whitman Lake Hydroelectric Project Feasibility Study $12,783,000 $1,044,000 $193,000 $1,237,000 Tan August 1998 4. Least Cost Alternative 4.1 Description This alternative assumes full enforcement of the 1978 agreement between KPU and SSRAA, whereby KPU could construct its hydroelectric facility without regard for SSRAA’s water supply or facility needs. If KPU elected to pursue this course of action, the three main features of the Preferred Alternative that we would recommend modifying are the turbine capacity, powerhouse location and reservoir operating criteria. A single turbine/generator unit, rated at 3,900 kW, would be more economical than installing an additional smaller unit as proposed in the Preferred Alternative. The need for the smaller unit is justified wnen the purpose of the project is to minimize impact to the hatchery’s water supply. However, if the hatchery’s water supply is not considered in the design criteria for the hydroelectric project, then the reservoir operating criteria can be modified to respond more to the rate of precipitation and watershed runoff than to hatchery water supply demands. Consequently, a single turbine could be justified. In addition to downsizing the plant capacity in this project alternative, the ideal powerhouse location would be where the existing pressure reducing valve (PRV) building is now located. This is approximately the same location that the original powerhouse was constructed in the early 1900's. 4.2 Estimated Energy Generation The Least Cost Alternative will generate an average of 19,946 MWh annually. Based on an installed plant capacity of 3.9 MW, the project will operate at a 58 percent plant factor. Results of the energy generation analysis are presented in Table A-11. 4.3 Project Costs The Direct Construction Cost of this alternative, including contingencies, is estimated to be $5,253,000 based on a January 1998 bid price level. Total Capital Requirements are estimated to be $8,488,000. Detailed project costs are shown in Tables A-12 through A-14. First year cost of energy is 4.4 cents/kWh. Whitman Lake Hydroelectric Project A-9 Feasibility Study Appendix A TABLE A-11 KPU HYDROELECTRIC FEASIBILITY STUDY ANNUAL ENERGY GENERATION ANALYSIS Whitman Lake Project - Least Cost Alternative ANALYSIS SUMMARY: Physical and Operating Statistics: Target EOM Reservoir El. AVERAGE ANNUAL GENERATION = 19,946 MWH Unit 1 Rated Capacity = 3900 kW Jan 380 UNIT 1 GENERATION = 19,946 MWH Unit 2 Rated Capacity = 0 kW | Feb 376 UNIT 2 GENERATION = 0 MWH Unit 1 Design Discharge = 150 cfs Mar 375 AVERAGE SPILL = 7.6 cfs Unit 2 Design Discharge 0 cfs Apr 368 AVG. EOM RES. EL. = 374.5 ft Penstock Diameter = 48 inches May 374 AVG. NET HEAD, UNIT 1 = 346.6 ft Penstock Length = 2220 feet “Jun 378 AVG. NET HEAD, UNIT 2 = 374.5 Spillway Crest El. = 380 Jul 369 |AVG. ANNUAL PLANT FACTOR = 0.58 Minimum Oper. Res. El. = 362 Aug 371 Unit 1 Tailwater El. 20 Spt 362, Unit 2 Tailwater El. = 0 Oct 370 Hatchery Flow = 0 cfs Nov 376 Dec 379 Hatchery Excess Hatchery] flow | instream] Flow Average | Unit 2 | Unit 1 Total Total Calculated | Storage | Average| Flow from| withdrawn] Flow in | Above | Available Monthly | Average | Average Monthly | Annual i Turbine Turbine 1 Turbine 2 | Spillway | Net Net Unit 1 | Delivered | Delivered Flow, Discharge, | Discharge, | Discharge] Head, | Head, | Generation] Generation | Generation cts cfs. cts cts feet feet_| MWH MWH MWH __ 120 o} 4.5 52 o} 00 34 o} 00 23 o} 00 127 ) 36 0} 00 55 o| 00 99 ) 181 o| 46 127 o| 324 82 o| 00 156 o| 08 18,720 Whitman Lake Hydroelectric Project Least Cost Alternative Hatchery Excess Hatchery flow instream Flow Average Unit 1 Total Total Calculated | Storage Average] Flow from] withdrawn} Flow in | Above Available Monthly Average Monthly Annual Target | Calculated} Target EOM surplus or | Monthly | Whitman from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Unit 1 Delivered | Delivered EOM EOM EOM Storage shortage Inflow, inflow storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge Head, | Generation | Generation | Generation Month | Year | Res. El. | Res.El. | Storage af af cfs cfs cfs cfs cfs cfs cfs cfs cfs feet MWH MWH MWH oct | 1921] 370 | 3869 | s710 | ates | 745 | 2282] oof oof, oto, wt.a] ton] tof =o as | 2714 ‘Nov | 1921] 376 | 3758 | 6556 | 6529 1630 1168] 00! ~~ 00 0.0 18.4 109] 109 on) __ 2,037 179.4 147] 168 oO} 17 2,756 23.0) 07 23} of 396 12.4 orf tof 0 281 02 ee: 18 0 303 42) 78} i) 1,354 nay 125 ol 0 2.340 - o| 24 2,651 - Oo} 163 1,985 0} 00 843 2,597 o 20,268 149} __ 150 2 : 52} 0 _ a} pF] 0 - 7o| iO 0. __ 148} __ o 116} si — oO oO 0 20,794 0 21,896 Page 2 of 5 Whitman Lake Hydroelectric Project Least Cost Alternative Hatchery Excess Hatchery flow Instream Flow Average | Unit 2 Unit 1 Total Total Calculated Storage Average] Flow from] withdrawn} Flow in Above Available Monthly | Average | Average Monthly Annual Calculated} Target EOM surplus or | Monthly | Whitman from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Net Unit 1 Delivered | Delivered EOM EOM Storage shortage Inflow, inflow storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge] Head, Head, | Generation | Generation | Generation Res. El. Storage af af cfs cfs cfs cfs cfs cfs cfs cfs cfs feet feet MWH MWH MWH __ 369.9 __ 5710 | 5700 1773 _ 170.2} 0.0) 00} 00 456 148) 148) 0) 51.2 376.1 | 3394 | 2,800 2,723 | 3759 | 6556 | 6543 856 | 159.2) 00 oo} 35] 247] 141 05 | 3729 | 3377 | 2569 | 2498 _ 3787 | 6993 | 6949 450 | 656 00] oof 40} 954 927 3799 | 7140 | 7125 -191 26.9) oo] oo 40 08 351 341 3756 6556 6503 569 138] 0.0] =~ 0.0],— 35] 7} 331 | 322 3749 | 6412 | 6404 90 414 oo} 0.0 40 04 675 | 656 367.6 4.0 42 1,393 1,355 717 697 17,841 2 & lo ° } e 4 a n os: S ‘2 a a 2 lololo 650 20,964 = elolololo 765 521 _856__ 1,270 1,898 2,231 2,271 _ 1,289 2399 | 18,462 Page 3 of 5 Whitman Lake Hydroelectric Project Least Cost Alternative Hatchery Excess Hatchery flow Instream Flow Average | Unit 2 Unit 1 Total Total Calculated Storage Average} Flow from} withdrawn} Flow in Above Available Monthly | Average | Average Monthly Annual Target | Calculated] Target EOM surplus or | Monthly | Whitman. from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Net Unit 1 Delivered | Delivered Storage shortage Inflow, inflow storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge} Head, Head, | Generation | Generation | Generation af af cfs cfs cfs cfs cfs cfs cfs cfs cfs feet feet MWH MWH MWH _ 5656 | 1072 154.6 oo] 33 41.4) 134) 134] o| 07 365.8 | 3321 | 2,510 2,441 18,662 18,025 4 4 a) Stee _9 —_9 _ Of _ i — ol oe 0 0} 17,930 Page 4 of 5 Whitman Lake Hydroelectric Project Least Cost Alternative Hatchery Excess Hatchery flow instream Flow Average | Unit 2 Unit 1 Total Total Calculated Storage Average} Flow from} withdrawn} Flow in Above Available Monthly | Average | Average Monthly Annual Target | Calculated} Target —EOM surplus or | Monthly | Whitman. from Excess | Turbine Turbine Turbine 1 Turbine 2 Spillway Net Net Unit 1 Delivered | Delivered EOM EOM EOM Storage shortage Inflow, inflow storage | of Spill, | Capacity, Flow, Discharge, Discharge, | Discharge] Head, Head, | Generation | Generation | Generation Month | Year | Res. El. | Res. El. Storage af af cfs cfs cfs cfs cfs cfs cfs cfs cfs feet feet MWH MWH MWH 0.0 13.5 33.0 | 469 24,814 20,970 Page 5 of 5 Table A-12 WHITMAN LAKE HYDROELECTRIC PROJECT CONSTRUCTION COST ESTIMATE LEAST COST ALTERNATIVE FERC FERC ACCT. ACCT NO. DESCRIPTION QUANTITY TOTAL 330 Land and Land Rights USFS Special Use Permit, Lot Easement LS $25,000 Total Acct. 330 $25,000 331 Structures and Improvements T Care of Water LS $20,000 Clearing and Grubbing LS $8,000 Excavation Powerhouse 2100 CY 40 $84,000 Tailrace 350 CY 25 $8,750 Backfill 600 CY 18 $10,800 Gravel Surfacing 60 CY 20 $1,200 Landscaping and Revegetation LS $3,000 Riprap 200 CY 75 $15,000 Concrete Substructure 520 cY 450 $234,000 Tailrace 100 CY 450 $45,000 Insulated Metal Building Superstructure 2400 SF 65 $156,000 Miscellaneous Metals LS $25,000 Grounding Grid and Connections LS $8,000 Fire Protection LS $12,000 Drainage System LS $8,000 Office Equipment LS $10,000 Construction Surveying - General Cont. LS $40,000 Mob/Demob - General Contract LS $300,000 Total Acct. 331 $988,750 Continued next page Whitman Lake Hydroelectric Project Feasibility Study Page 1 of 3 August 1998 Table A-12 (continued) Least Cost Alternative FERC FERC ACCT. ACCT NO. DESCRIPTION QUANTITY TOTAL Reservoirs, Dams and Waterways Care of Water LS $15,000 Clearing and Grubbing LS $40,000 Dredging and Removal of Timber Crib Dam LS $60,000 Structural Improvements to Existing Dam LS $125,000 Excavation Shallow/Common Excavation 850} CY 20] $ 17,000 Rock Excavation (buried pipe section) 600 CY 50} $ 30,000 Backfill Select Fill 230 cY 22) $ 5,060 Random Fill (from trench excavation) 280 CY 12) $ 3,360 48-inch Diameter Steel Pipe Bare Pipe 3/16" wall thickness 1700 LF 77| $ 130,900 1/4" wall thickness 320 LF 91) $ 29,120 5/16" wall thickness 200 LF 105} $ 21,000 Pipe Shipping 4 LS 43,000} $ 43,000 Pipe Installation LS $ 217,000 Concrete Pipe Supports 33 EA 3,500] $ 115,500 Concrete Pipe Anchors 16 EA 4,500} $ 72,000 Expansion Joints LS $ 5,000 Pipe Connection to Existing Outlets LS $ 25,000 Trashrack Ls $ 20,000 Diversion Facilities (two sites) Diversion and Care of Water LS $ 10,000 Clearing and Grubbing LS $ 20,000 Excavation (at check dams) 100 CY 120] $ 12,000 Backfill (at check dams) 240 CY 40/$ 9,600 Concrete Check Dams 10 CY 1,500} $ 15,000 Pipe supports/anchors 35} CY 1,500} $ 52,500 Gates/Miscellaneous Metal LS $ 9,000 16" Dia. HDPE Pipe 1760 LF 18} $ 31,680 24" Dia. HDPE Pipe 1600 LF 30} $ 48,000 Pipe Installation LS $ 119,520 Revegetation LS $ 10,000 Total Acct. 332 $1,311,240 333 Turbines and Generators 3900 kW Turbine/Generator Unit LS $ 770,000 Generator Cooling System LS $ 60,000 42" Turbine Inlet Butterfly Valve LS $ 26,000 18" Synchronous Bypass Valve, Piping Ls $ 80,000 Equipment Installation LS $ 68,000 Units Testing and Startup LS $ 15,000 Construction Surveying - Equip. Cont. LS $ 14,000 Mob/Demob - Equipment Contract LS $ 150,000 Total Acct. 333 | $ 1,183,000 Whitman Lake Hydroelectric Project Feasibility Study Page 2 of 3 Continued next page August 1998 Table A-12 (continued) Least Cost Alternative FERC ACCT NO. DESCRIPTION Accessory Electrical Equipment QUANTITY FERC ACCT. TOTAL Control and Protection System LS $ 310,000 4.16 kV Metal-Clad Switchgear LS $ 80,000 Station Service Power System LS $ 90,000 DC Power System LS $ 32,000 Cables, Conduits, Trays, Accessories LS $ 55,000 Reservoir Level Measurement System LS $ 30,000 Lighting LS $ 18,000 Unit Heaters LS $ 4,000 Total Acct. 334 | $ 619,000 335 Miscellaneous Power Plant Equipment 7.5 ton Hoist, Rails and Structural Supports LS $ 18,000 Ventilation Fans and Louvers LS $ 4,000 Sump Pump and Oil Separator LS $ 15,000 Total Acct. 335 | $ 37,000 336 Roads, Railroads and Bridges Gravel Surface Access Road 500 LF 16] $ 8,000 18" Culvert and Erosion Protection LS $ 3,000 Total Acct. 336 | $ 11,000 353 Switchyard Grading and Gravel Surfacing LS $ 3,000 Concrete Equipment Pads LS $ 6,000 Transformer, Circuit Breakers, Disconnects LS $ 280,000 Grounding Grid and Connections LS $ 15,000 Fencing, Gate LS $ 4,000 Lighting LS $ 8,000 Total Acct. 353 | $ 316,000 355 Poles and Fixtures LS $ 22,000 Total Acct. 355 | $ 22,000 356 Overhead Conductors and Devices LS $ 15,000 Total Acct. 356 | $ 15,000 Whitman Lake Hydroelectric Project Feasibility Study Page 3 of 3 DIRECT CONSTRUCTION COST $4,528,000 August 1998 Table A-13 WHITMAN LAKE HYDROELECTRIC PROJECT Least Cost Alternative PROJECT COST ESTIMATE SUMMARY FERC TOTAL ACCT DESCRIPTION COST COSTS 330 Land and Land Rights $25,000 331 Structures and Improvements $989,000 332 Reservoirs, Dams and Waterways $1,311,000 333 Turbines and Generators $1,183,000 334 Accessory Electrical Equipment $619,000 335 Miscellaneous Power Plant Equipment $37,000 336 Roads, Railroads and Bridges $11,000 353 Switchyard $316,000 355 Poles and Fixtures $22,000 356 Overhead Conductors and Devices $15,000 Direct Construction Cost $4,528,000 Contingency (Accounts 333,334), 10% $180,000 Contingency (All other Accounts), 20% $545,000 Direct Construction Cost Plus Contingencies $5,253,000 Owner Administration $100,000 Engineering and Licensing: FERC Licensing and Other Permits $210,000 Final Design and Field Studies $450,000 Construction Management $230,000 Total Construction Cost $6,243,000 Interest During Construction (6%/yr) $350,000 Total Investment Cost (bid Jan 98, on-line Spt 99) $6,593,000 Escalation to Proposed Bid Date (3.0%/yr) $883,000 Total Investment Cost (bid Apr 02, on-line Dec 03) $7,476,000 Total Investment Cost per Installed kW $1,411 Whitman Lake Hydroelectric Project Feasibility Study August 1998 TABLE A-14 WHITMAN LAKE HYDROELECTRIC PROJECT Least Cost Alternative ESTIMATED CAPITAL AND ANNUAL COSTS CAPITAL COSTS Total Investment Cost Financing Expenses Bond Reserve Working Capital Reserve TOTAL CAPITAL REQUIREMENTS ANNUAL COSTS Fixed Costs Debt Service Less Earnings on Reserves Total Fixed Costs Variable Costs Operation and Maintenance Administrative and General Expenses FERC Compliance Interim Replacements Insurance Total Variable Costs TOTAL ANNUAL COSTS (First Year) $7,476,000 $212,000 $740,000 $60,000 $740,000 $48,000 $120,000 $25,000 $8,000 $25,000 $15,000 FIRST YEAR COST OF ENERGY (cents/kWh) Assumptions: Annual Interest Rate on Bonds 6% Bond Term 20 years Reinvestment Rate 6% Financing Expenses 2.5 % of TCR Bond Reserve 1 year of debt service Working Capital Reserve 6 months of O&M costs Average Annual Energy 19,946 MWH Whitman Lake Hydroelectric Project Feasibility Study $8,488,000 $692,000 $193,000 $885,000 4.4 August 1998 APPENDIX B Geotechnical Report KETCHIKAN PUBLIC UTILITIES HYDROELECTRIC RECONNAISSANCE GEOTECHNICAL STUDY WHITMAN, CARLANNA & CONNELL LAKES Prepared for: WESCORP 18021 15th Ave., N.E., Suite 101 Shoreline, WA 98155 Prepared by: R&M ENGINEERING, INC. 6205 Glacier Highway P.O. Box 34278 Juneau, AK 99803 R&M Project No. 972116 December 19, 1997 TABLE OF CONTENTS INTRODUCTION Score aecess eee ee erro eee niet ce ceenee nce enee 1 PURPOSE Spm cricei aie sais aie sie ites iiieetae eae nein aieieree Giereiee ar 1 SCOPE OF GEOTECHNICAL STUDY ................. 0.000 1 REGIONAL IGEQLOGY, Wrens a see ee eels orice ee eae dele seine 2 AREA BEDROCK GEOLOGY ... 2.20006. 2 GLACIATION Fogg ssaae ae eerie ace eae sae cca ee oeelce ia oe 2 SEISMICIGY Serre aaron ies son ace ame ie ere gee eerie 2 SITE SPECIFIC GEOTECHNICAL CONSIDERATIONS ................00000 0000 c eee eeee 3 IW EET MAIN SICAKSE pre cetere ter ctiatey sit Greve sree sited ale) oleate oeaseieireiereisrsnieer ail 3 CARLANNA LAKE .... 2.0... 006 cee ee ce eee e teens tense eee eeeeeees 5 GCONNELE RAKE n eger se ee Cerise nee oro eee enero eee eeee 6 (2) HON ON Sep otopice cnc ciceou ce Ges eMoeennc one cnadcccocicioe code com moron cine ertce naenr: 8 SELECTED REFERENCED feces does ee oe ee aeiaee soba ae sete eee sue dae 9 DIVISIONIGE eee een oe eee Oe eee eee eee ern ee nee eee MAPS DIVISION I Sosa ose eee cae nie eee ae oe eee sae PHOTOGRAPHS KETCHIKAN PUBLIC UTILITIES HYDROELECTRIC RECONNAISSANCE GEOTECHNICAL STUDY Whitman, Carlanna & Connell Lakes INTRODUCTION PURPOSE Ketchikan Public Utilities (KPU) is currently operating their hydroelectric generating facilities near maximum capacity. In an effort to locate additional hydroelectric resources, KPU has asked Wescorp of Seattle, Washington to conduct preliminary studies of three potential hydro sites. R&M Engineering was engaged by Wescorp to provide geotechnical services in connection with this study. The purpose of this geotechnical report is to provide a preliminary evaluation of the geologic conditions at the three hydroelectric sites. The sites being considered are Whitman Lake, Carlanna Lake and Connell Lake (See location map Drawing 1). Specifically, information was provided about foundation conditions, geologic hazards, sources of borrow materials, tunneling conditions (Whitman Lake) and scope of future geotechnical investigations. No sampling or test drilling was conducted in conjunction with this study. SCOPE OF GEOTECHNICAL STUDY Our geotechnical evaluation assessed the foundation conditions at proposed powerhouse, penstock and intake sites. Geologic hazards that could affect the location, alignment, or design of project features were discussed. Sources of borrow and usability of excavated material were assessed. Geologic conditions along the proposed Whitman Lake tunnel were assessed based on map and surface observations. Two field trips were accomplished: a preliminary site visit (August 20, 1997 - summarized in letter to Wescorp August 26, 1997) and a second trip to evaluate the powerhouse sites on November 5 and 6, 1997. Additionally a review of available topographic maps, aerial photographs and geologic reports/maps was conducted. This was a preliminary investigation to evaluate geotechnical aspects of the three sites, but is not intended to provide specific design or foundation recommendations. No test holes were drilled nor was any laboratory testing conducted. The on site studies were limited to observing existing outcrops and geomorphology. REGIONAL GEOLOGY AREA BEDROCK GEOLOGY Southeast Alaska is underlain by Quaternary surficial deposits and by sedimentary, volcanic, intrusive and metamorphosed rocks ranging in age from Quaternary to Precambrian (Gehrels, 1992). The area is within an active tectonic belt than borders the north Pacific Basin. The bedrock outcrop pattern is the result of late Mesozoic and Tertiary deformation and intrusive events (Brew, 1966). Large scale right-lateral strike-slip faulting is common. Most of this tectonic activity is the result of the North American continental plate colliding with the Pacific plate. The physical manifestation in the bedrock structure is the general northwest- southeast trend of the major mountain ranges and waterways of Southeast Alaska. The pre-Cenozoic strata (basically the bedrock) in the Ketchikan area has been divided into five fault bounded rock assemblages: Alexander terrain, Gravina-Nutzotin belt, Taku terrain, Tracy Arm terrain and Stikine terrain (Berg and others, 1988). All three hydroelectric sites are in the Taku terrain (Drawing 1). In the study area the Taku terrain consist of Tertiary gabbro and Cretaceous granodiorite and quartzdiorite igneous intrusive rocks, Mesozoic or Paleozoic metasedimentary rocks and Mesozoic or Paleozoic metavolcanic rocks (Drawing 2). GLACIATION Southeast Alaska, except for the highest peaks, was covered by ice during the late Pleistocene ice ages. The glacier ice varied in maximum thickness from 2000 feet near the outside coast line to 6000 feet in the Coast Mountains (Drawing 4). In the Ketchikan area the surface of the ice was 3500 feet above present day sea level (Coulter and others, 1962). The present day topography of deep fiords, elongated lakes and steep sided U-shaped valleys reflect the effects of glaciation. When the ice begin melting 10,000 years ago the glacial gouged valleys begin filling with sea water. At the time sea level was over 300! higher than it is today. Over time the land rose relative to sea level due to the unloading of the ice and tectonic forces. Large amounts of silt and sand were deposited by outwash streams into the sea water, concurrently wave cut sand and gravel beaches were being formed along some of the shorelines. The bedrock mantling deposits left behind by the glaciers, outwash streams and seawater include glacial till, alluvium filled fiords, marine deposits and elevated beach deposits. Bedrock in the Ketchikan area is often exposed or at relatively shallow depths, the land having been scrapped bare by the passage of the glaciers. SEISMICITY Evaluating earthquake probability, strength and destructive affects is difficult if not impossible. The most common approach has been to review the area's earthquake history and its proximity to major active faults. With this information seismic zone maps are prepared that define design parameters for structures in each zone. See Drawing 5 for 1994 UBC Seismic Zone Map of Southeast Alaska. = aQWZMVM Southeast Alaska lies in one of the two most seismically active areas in Alaska. Since the turn of the century 8 earthquakes with magnitudes of 7 or greater have occurred and 23 with magnitudes between 7 and 5. However there are no recorded epicenters of earthquakes in the immediate Ketchikan area (Lemke, 1975). Within a radius of 100 miles there have been 2 quakes recorded with magnitudes between 6 and 7, other 100 mile radius earthquakes have been less than magnitude 5 (Drawing 4). Geologic mapping has indicated the existence of several faults in the Ketchikan area (Drawing 6). Most of these faults are structural manifestations of faulting that occurred in the Mesozoic Era. However they do represent weak zones along which faulting could again occur. An active fault, and the one along which Southeast Alaska's strongest recent earthquakes have occurred, is the Fairweather-Queen Charlotte fault system. This fault roughly parallels the coast line, and at its closest point is over 100 miles from Ketchikan. An earthquake strong enough to cause major damage in Ketchikan would most likely occur along the Fairweather-Queen Charlotte Fault. Predicting the effects of such an earthquake is problematical. Some of the destructive events associated with strong ground motion are: surface displacement, ground shaking, compaction, liquefaction, slides, slumps, water ejection and seismic waves. SITE SPECIFIC GEOTECHNICAL CONSIDERATIONS WHITMAN LAKE Whitman Lake is located four miles east of Ketchikan . It's outlet stream flows into Herring Bay on Carroll Inlet. Two alternative projects arrangements are being considered. The first is a lake tap with a 1,650' long tunnel and 900' long steel penstock conveying water to a powerhouse at Herring Cove. The second is to take water from the base of the existing dam, or new dam just downstream of it, and convey the water in a penstock following the existing hatchery pipeline alignment. The powerhouse would be located near the SSARAA hatchery incubation building. The current dam is a concrete arch structure that is approximately 35' high. The structure is keyed into bedrock. The bedrock outcropping at the base of the dam is a hard dense metagraywacke with garnet inclusions. The apparent bedding strikes 276 degrees and dips 80 degrees north. This structural orientation is nearly perpendicular to the face of the dam. The outlet stream coarse is a steep sided bedrock canyon. The bedrock is a relatively massive metagraywacke with widely spaced fractures (1' to 10'). The rock is generally hard, unweathered and strong, but tends to part along preferred cleavages. Dam construction will require the removal of loose rock and stream bed deposits. The bedrock should provide a suitable foundation for the proposed dam. Some grouting may be required to seal the fractures. The existing penstock route is over shallow bedrock. Holes dug for the hatchery pipeline support improvements showed thin organics and roots over shallow colluvial angular cobble sized rocks mixed with sand and silt. Those excavations observed were less than 2.0' deep to bedrock. Penstock burial would require blasting and is not considered a good alternative to above ground placement of the penstock. The proposed lake tap tunnel would be thru metamorphosed phyllite and homfels. The phyllite contains some schistose zones. The bedrock is in a contact metamorphism aureole surrounding the Tertiary gabbro pluton north of Whitman Lake. The major manifestation of this metamorphism are the large (0.1" to 0.5") pyroxene crystals in the fine grained groundmass (hornfels texture). The bedrock outcropping at the cliff near the proposed tunnel outlet portal is cut by widely spaced joints (1' to 4’). A tunnel in this bedrock will require some grouting to seal the joints and rock bolting in some fractured areas to prevent rock falls. Some schistose zones may require lining. It is estimated from surface outcrops that less than 10% of the tunnel will require lining. However, a minimum of three test borings along the tunnel alignment are required to further assess the tunneling conditions. Test borings are recommended to extend at least 5' below the proposed tunnel floor elevation. The waste rock from the tunneling operation will be suitable for embankment and rock fill dam core material. However much of it will be phyllite which is unsuitable for concrete aggregate. The penstock route from the tunnel portal to the powerhouse is over hornfels/phyllite bedrock and colluvium covered with thin forest soils and roots. The vegetation is spruce and hemlock trees with an understory of blueberry, devils club and other brush. The depth to bedrock along the entire penstock route is unknown. However surface indications are that it is generally shallow, indicating that an above ground penstock would be most feasible. Two powerhouse sites were considered. Both are immediately north of the Southern Southeast Alaska Regional Aquaculture Association (SSARAA) salmon hatchery at Herring Bay. The alternate | site is northeast of the rearing ponds and the alternate 2 site is immediately north of the main hatchery building. The #1 site is in line with the lake tap tunnel option. The #2 site is near the routing for the dam intake option, adjacent to the terminus of the present hatchery water line. Geotechnically both the areas "behind" the hatchery being considered for powerhouses are similar. Spruce/hemlock forest growing from thin forest soils. Bedrock is shallow, covered with colluvium and blocky boulders to 6'. The powerhouses will be founded on bedrock after the organics, forest soil and colluvium are removed. Some blasting may be required to provide level footing pads. The tail race near the powerhouses could be blasted from the bedrock. However some grouting will be required to prevent leakage in the rocks natural fracture zones. A portion of the tailraces will cross the man made fill and marine estuary zone, some type of lining will be required in these areas to prevent erosion of these soft deposits. Both powerhouses should be relocated 200' east of their proposed sites to more suitable terrain. This would place the alternate 1 site on a natural bench approximately 40' above the hatchery rearing ponds. Moving the alternate 2 site 200' east will move it off a steep boulder covered hillside to gentler sloping terrain. A quarry could be developed in the project area to procure material suitable for a rock fill dam. Bedrock in the area is generally near the surface (covered with less than 2.0' of overburden). However, phyllite is one of the rock types known to react deleteriously when used as concrete aggregate (Concrete Manual, US Bureau of Reclamation). Therefore concrete aggregate will have to be acquired from another source. 2M fat Generally sand and gravel deposits suitable for the production of concrete aggregate are not available along the Ketchikan road system. Aggregate is either produced from quarry rock or imported by barge. Ketchikan Ready Mix is the commercial source of concrete in the Ketchikan area. The three possible diversion dam sites are all on steep terrain. Insufficient data is available to accurately evaluate all the factors affecting slope stability. Slope angle, soil type, soil depth, bedrock type, bedrock structure, faults, fractures, water availability, soil moisture. However some generalizations can be made. The slope angles in the areas of the diversions range from 22 degrees to 30 degrees. Generally slopes steeper than 30 degrees are considered potentially unstable. The general geology of the area is one of shallow forest soils over bedrock. Two types of slides are common in these conditions, Transnational slides and debris slides. Transnational slides are controlled by the interface between surficial material and bedrock. Slides of this type are shallow but may extend a considerable distance. Heavy rainfall is often the triggering mechanism. Debris slides begin as small slides on steep thinly mantled bedrock slopes. They tend to follow steep "V" notched gullies picking up material as they accelerate downslope. They are also often triggered by heavy rainfall. A third factor affecting small diversion dams in steep narrow drainages is the large bedloads transported during periods of heavy rainfall. Our experience with small water supply and hydro dams in the steep canyons of Southeast Alaska is that after a period of a few years small dams (less than 5' high) become plugged with granular soils (silt to cobbles) and organic debris. Diversion dams in steep canyons would require at least annual cleaning to remain effective. The diversion dams are in areas potentially threatened by slides and will require clearing of bedload debris to remain effective. The major detrimental affect of a strong earthquake to the proposed facilities would be caused by the triggering of slides. The only structures in areas likely to be impacted by slides are the diversion structures. However slides could impact Whitman Lake causing a potentially damaging seiche wave to impact or overtop the dam. In 1949 a earthquake caused a 2 foot high seiche wave in Ward Lake, 5 miles northwest of Ketchikan. CARLANNA LAKE Carlanna Lake is located 2.5 miles northwest of downtown Ketchikan. Its outlet creek flows approximately | 3/4 mile south into Tongass Narrows. Carlanna Creek is contained in a steep sided gorge as much as 100! deep. The proposed project will utilize the existing dam with a steel penstock carrying water to a powerhouse near Carlanna Creek and Hunt Way (one block upstream of Tongass Ave.). The dam is a concrete faced rockfill structure founded on bedrock, The bedrock is a gray massive metagraywacke with an irregular joint pattern. No changes are planned for the existing dam structure. The upper portion (approximately 200') of the penstock may have to be above ground. Bedrock out crops are numerous in this area, indicating shallow soils. A test pit will be required to accurately determine if there is sufficient suitable soil for pipeline burial. es — UV) The lower portion of the penstock can be buried. This portion begins at the access gate on Canyon Road and extends to the cliff just above the powerhouse. Much of this alignment is in an existing utility corridor. The proposed powerhouse location is at the base of a cliff on the bank of Carlanna Creek, approximately 800' from Tongass Narrows. The bedrock outcropping in the vicinity of the proposed powerhouse is brown irregularly banded metasediment with abundant quartz stringers. Cliffs and scaled rock slopes in the are standing at 1/4:1 slopes. The soils in the area of the proposed powerhouse are a mixture of rock fall and stream flood deposits. They are poorly consolidated and will require removal and replacement before the foundation is constructed. Indications from the Carlanna Creek cut bank are that these deposits are on the order of 8' thick over bedrock. The rock slope behind the powerhouse site could be cleared of loose rock and organics and be stable at 1/4:1 slopes. Scaling and reshaping of this cliff slope may jeopardize the house at the top of the cliff (on Tower Rd). Moving the powerhouse 50! east to the site now occupied by a trailer house (201 Hunt Street) has two geotechnical advantages. First it will position the powerhouse far enough from the cliff to eliminate the need to disturb the cliff below the house on Tower Road. Second it will likely place the powerhouse on stable foundation soils eliminating requirement to excavate and replace the soil at the presently proposed location. Test borings will be required to determine the exact foundation soil conditions. There is one proposed diversion structure planned to increase the area of the projects drainage basin. The proposed diversion dam is at the base of a 30 degree slope. It is subject to potential transnational and debris slides as discussed for the Whitman Lake diversions. The diversion dam is in an area potentially threatened by slides and will require clearing of bedload debris to remain effective. Ketchikan Ready Mix is located 1/2 mile northwest and is probably the most economical source of construction material for this project. CONNELL LAKE (WARD COVE) Ward Cove is approximately 8 miles northwest of Ketchikan. The Ward Cove facility proposes to use the existing Ketchikan Pulp wood stave pipeline from Connell Lake to the pulp mill site at Ward Cove as a source of generation water. The wood stave pipe will be connected to a steel penstock leading to the powerhouse. The existing dam is a large reinforced concrete structure founded in bedrock. The bedrock is graywacke and phyllite with some schistose zones. No changes are planned for the existing dam. The wood stave pipeline is approximately 3.1 miles long. With the exception of two tunnels (totaling 0.3 mi) it is founded on concrete footings resting on a roadbed type embankment. Total embankment width is 12', providing room for the pipeline and an 8' wide maintenance road. In two locations the pipeline has been impacted by transnational slides (0.2 mi and 0.6 mi from the dam). The first slide averages 100' wide and released from the 775' high knob just east of the dam. It crossed the access road and pipeline and traveled an additional 250' to Ward Creek. The second slide is similar in nature but much smaller, only 35' wide. Both slides bared the slopes down to weathered and fractured schistose bedrock. The pipeline in both these sections has been converted to 48" plastic and buried in a protective berm averaging 10' thick. These defensive structures are adequate to protect it from potential future slides. Since its completion in 1952 the pipeline has not been impacted by any slides other than the two already discussed (conversation with Dan Loitz, KP Planning and Engineering). However over most of its length the pipeline is within 1000' of the base of slope of a steep (average 35 degrees) high (1300') ridge. Slides with runouts long enough to reach the pipeline are possible, especially during periods of heavy rainfall. Two powerhouse locations are being considered. One on KP property at Ward Cove and the other at the upper end of the Ward Cove estuary . Dan Loitz, Engineer for KP, thought that citing the powerhouse on the KP property at Ward Cove seems unlikely because of site commitments to the KP Sawmill and planned usages of the pulp mill site for a veneer mill. The KP property at Ward Cove can be divided into three broad foundation soils situations. The sloping higher elevation terrain is generally bedrock or shallow soils over bedrock. The level areas below elevation 30' were constructed by end dumping shot rock on top of in-situ intertidal and marine sediments. The shot rock was not consolidated (November 11, 1996 interview with Ralph Dale, KP Engineer). In November of 1995 R&M Engineering drilled a test hole adjacent to the machine shop that indicated 41' of shot rock over 20' of marine sediments. The third area is presently occupied by the KP Sawmill. This area was used for disposal of overburden soils and waste during construction of the pulpmill. Pilings for recently constructed sawmill building were driven to over 115' (November 6, 1997 interview - Dan Loitz, KP Engineer). The second powerhouse site at the upper end of the Ward Cove estuary will be connected to the existing pipeline by a 1700' long steel penstock. The soils for the penstock route and the powerhouse site are very similar. The area being considered for these structures is second growth spruce and hemlock forest growing out of thin forest soils. Bedrock outcrops and large surface boulders are common. The exception to this is the section starting at the under construction forest road and extending 150' downhill of it. This area is a forested wetland with organic soils that may be as much as S' thick. It appears from our reconnaissance that the steel penstock should be above ground. The foundation for the powerhouse will most likely be on bedrock. We recommend drilling at least two test holes at the final powerhouse locations to obtain the soils information necessary for foundation design. Construction materials for this site will most likely be from processed shot rock from an as yet unidentified source. To increase runoff area a diversion dam and pipeline are planned for the headwaters of the White River drainage. The dam is planned for a wide low swale with muskeg soils on the east side and diorite bedrock outcrops on the west side. The stream bed is composed of subrounded sand and gravel. A rock fill dam will probably be constructed diverting water into a pipeline. Due to the variety of soils evident at the site general soils conditions cannot be estimated. SSM We recommend a geotechnical investigation that includes at least two test borings be conducted to obtain the required dam foundation information. The diversion pipeline as planned does not traverse any slide hazard areas. CLOSURE It has been a pleasure working with you on this project. Should there be questions, or if we may be of further assistance, please do not hesitate to contact us at your convenience. Sincerely, R&M ENGINEERING, INC. pif! Ralph Swedell Malcolm A. Menzies, P.E. Engineering Geologist Civil Engineer Ysh Sise™M SELECTED REFERENCES Berg, H. C., Elliott, R. L., and Koch, R. D., 1988 Geologic Map of the Ketchikan and Prince Rupert Quadrangles, Southeastern Alaska, USGS Map I-1807. Buddington, A. F. and Chapin, T., 1929, Geology and Mineral Deposits of Southeastern Alaska, USGS Bulletin 800. Coulter, H. W. and others, 1965, Map Showing Extent of Glaciation in Alaska, USGS Map I-415. Gehrels, G. E. and Berg, H. C., 1992, Geologic Map of Southeastern Alaska, USGS Map I-1876, 1992. Lemke, R. W., 1974, Reconnaissance Engineering Geology of the Wrangell Area, Alaska, USGS Open File Report 74-1062. Open File Report. Lemke, R. W., 1975, Reconnaissance Engineering Geology of the Ketchikan Area, Alaska, USGS Open File Report 75-250. Lemke, R. Wk. and Yehle, L. A., 1972, Regional and Other General Factors Bearing on Evaluation of Earthquake and Other Geologic Hazards to Coastal Communities of Southeastern Alaska, USGS, USGS Open File Report Preliminary. Selkregg, L. L. and others, 1977, Alaska Regional Profiles, Southeast Region, University of Alaska. Terzaghi, K., Peck, R. B., Mesri, G., 1996, Soil Mechanics in Engineering Practice. Turner, A. K., Schuster, R. L., 1996, Landslides Investigation and Mitigation, Transportation Research Board Special Report 247. US Bureau of Reclamation, 1966, Concrete Manual. Wolff, E. N. and Heiner, L. E., 1971, Mineral Resources of Southeastern Alaska, University of Alaska MIRL Report No. 28. C:AWP61\REPORTSI972116.REP 2S at R & M ENGINEERING, INC. CONNELL == ee ur LAKE “Ar j GP AS ttt CARLANNA LAKE SITE LOWER KETCHIKAN LAKE WHITMAN SCALE IN MILES LOCATION MAP KPU HYDROELECTRIC 0 . 75 FEASIBILITY STUDY DATE DRAWN BY CHECKED BY PROJECT NO. ( 11-24-97 K.P. | R.S. 972116 | 1 OF 10 9721 16/LOCMAP. DWG/FIT LEGEND; R & M ENGINEERING, INC. TECTONOSTRATIGRAPHIC TERRAINE GN_| GRAVINA—NUTZOTIN BELT ALEXANDER TERRAINE eee HIGH-ANGLE FAULT ra CRAIGSUBTERRAINE Aa | ANNETTE SUBTERRAINE ae THRUST FAULT TK | TAKU TERRAINE —?A— —?— UNDEFINED BOUNDARY OF TERRAINE Ta_| TRACEY ARM TERRAINE ST} STIKINE TERRAINE Revillagigedo Island Ketchika SAXMAN BASED ON 1994 UNIFORM GEOLOGIC TERRAINE BUILDING CODE, FIGURE 16-2 UNITS SCALE IN MILES KPU HYDROELECTRIC FEASIBILITY STUDY CHECKED BY 5 R.S. 972116 2 OF 10 9721 16/KET—GEO.DWG/1:1 R & M ENGINEERING, INC. CONNELL LAKE SITE WHITMAN LAKE SITE PLAGICLASE—PORPHYRITIC GRANODIORITE AND \ QUARTZ DIORITE (CRETACEOUS) nl GABBRO (TERTIARY) METAVOLCANIC ROCKS SCALE IN MILES GEOLOGIC MAP — KPU HYDROELECTRIC ; = : FEASIBILITY STUDY Crzesr | normo | ee | es | arene | 3 oF 10 972116/GEO.UWG/FIT ors 2 c\ oS aon (ee) NZ INSOVNN Y, SCALE IN MILES BB)? 7% y, 0 25 50 75 100 125 150 é eS tt FIGURE 3 ‘ TA MAP SHOWING SURFACE ’ (2 ss ELEVATION OF PLEISTOCENE 4 GLACIATION IN ™ * SOUTHEAST ALASKA (AFTER COULTER, 1962) DATE SCALE ~ DRAWN BY PROJECT NO. “DRAWING NO. ( 11-21-97 NOTED L K.P. »S- 972116 | 0 | y ¥ Ketchikan wow 972116/SE-GLAC.OWG/FIT NOTE; BASED ON 1994 UNIFORM BUILDING CODE, FIGURE 16-2 SCALE IN MILES 50° 75 + =100 125 150 FIGURE 6 SOUTHEAST ALASKA SEISMIC ZONE MAP DATE $eaLE DRAWH BY CHECKED BF PROTECT WO. DRAW WO. ( 11-20-97 NOTED | K.P. RS. ] 972116 5 OF 10 } 972116/SE-EARTH.OWG/FIT 134° | KPU HYDROELECTRIC FEASIBILITY STUDY CHECKED BY 5 2Se 972116 6 oF 10 pixon Entrance LEGEND WELL-DEFINED INFERRED pated Zee THRUST FAULT MAP OF SOUTHEASTERN ALASKA AND ADJACENT CANADA SHOWING MAJOR FAULTS CHECKED BY PROUECT WO. | 972116 DIVERSION “DAM —/ _ aad | PIPELINE “DIVERSION DAM PIPE! LINES se OL y DIVERSION GAM —srett Pree rT Air protect AL w...7 POWERHOUSE “yy S.SARAA. \\ HATCHERY Me ? J WHITMAN LAKE’ SITE K. corn HYDROELECTRIC FEASIBILITY STUDY CHECKED BY PROTECT WO 12/18/97 1” = 20 “P. RS. | 972116 972116/WHITMAN. DWG/1:2 APPENDIX C Turbine Vendor Cost Data BOUVIER HYDROPOWER, INC. BH [- . P lvania 19355 3 Spruce Road « Malvern, Pennsylv Fe SSINES Telephone: (610) 889-9900 « Fax: (610) 889-9901 &R EQUIPMENT November 5, 1997 WESCORP 18021 15th Avenue N.E., Suite 101 Seattle, WA 98155 Attention: Mr. D. Thompson Subject: Whitman Lake Hydro Project Dear Mr. Thompson: Thank you for your recent inquiry requesting budgetary price and technical information on hydroturbine equipment for the subject application. Based on the site net head data and discharge requirements submitted with your FAX of October 30, 1997, we propose two horizontal Francis type turbines each including synchronous generator and hydraulic pressure unit for operation of the wicket gates. Also included is a controls/switchgear package. The turbine configuration proposed has the turbine runner mounted directly onto the generator shaft resulting in a compact arrangement. The following data is submitted: Unit 1 Turbine Type - Horizontal Francis Runner Diameter - 775 mm Speed - 600 rpm Max. Turbine Output (@ 330 feet Net Head) - 3750 KW (150 cfs) Runner Centerline Setting to Tailwater - 6.5 ft above Tailwater Intake Type - Spiral Case Draft Tube Type - Elbow Runner Material - Stainless Steel Mr. D. Thompson Unit 1 (continued) Unit November 5, Turbine Performance at 330 feet Net Head: Output (KW) 3750 90.0 3450 92.0 3078 Sead 2438 92.0 1814 88.0 1153 83.0 Generator Type Generator Rating Speed Voltage Temperature Rise Power Factor Excitation 2 Turbine Type Runner Diameter Speed Max. Turbine Output (@ 350 feet Net Head) Runner Centerline Setting to Tailwater Efficiency (%) Flow (cfs) L510 135) 119) 95.4 74.2 50.0 Horizontal Synchronous 3700 KW (Nominal) 600 rpm 4160 V 80°C over 40°C Ambient 0.90 Brushless Horizontal Francis 450 mm 1200 rpm 1386 KW (53 cfs) 3.5 ft above Tailwater 1997 Mr. D. Thompson =-3- November 5, 1997 Unit 2 (continued) Intake Type - Spiral Case Draft Tube Type - Elbow Runner Material - Stainless Steel Turbine Performance at 350 feet Net Head: Output (KW) Efficiency (%) Flow (cfs 1386 88.0 53.50 1255 92.0 45.9 1163 92.7 42.2 930 910 34.4 802 89.0 30.3 637 85.7 25 Generator Type - Horizontal Synchronous Generator Rating - 1350 KW (Nominal) Speed - 1200 rpm Voltage - 4160 V Temperature Rise - 80°C over 40°C Ambient Power Factor - 0.90 Excitation - Brushless Our budgetary price for the above equipment is as follows: Turbines, Generators, HPU's and controls/switchgear - USS 1,570,000 Prices are F.O.B. Ketchikan, Alaska and include import duties. Delivery for the proposed approximately 11 months after contract award. The controls/switchgear will have full manual operation capability. Station service equipment transformer are not included. any applicable equipment is and automatic and main power Mr. D. Thompson -4- November 5, 1997 Should you have any questions or require additional information, please contact us. Very truly yours, BOUVIER HYDROPOWER, INC. Mark S. Barandy cc Mr. W. Benning; BHP BOUVIER HYDROPOWER, INC. [3 bf [> 3 Spruce Road « Maivem, Pennsylvania 19355 Telephone: (610) 889-9900 « Fax: (610) 889-9901 November 11, 1997 WESCORP 18021 15th Avenue N.E., Suite 101 Seattle, WA 98155 Attention: Mr. D. Thompson HYDRO TURBINES & EQUIPMENT Subject: Whitman Lake Hydro Project Dear Mr. Thompson: In reference to our recent discussions we have resized the larger Unit #1 to achieve a total powerhouse discharge of 175 cfs. The smaller unit (Unit #2) remains unchanged from that quoted in our letter of November 5. The following data is submitted: Unit 1 Turbine Type Runner Diameter Speed Max. Turbine Output (@ 330 feet Net Head) Runner Centerline Setting to Tailwater Intake Type Draft Tube Type Runner Material Horizontal Francis 730 mm 600 rpm 3021 KW (125 cfs) 6.5 ft above Tailwater Spiral Case Elbow Stainless Steel Turbine Performance at 330 feet Net Head: Output (KW) Efficiency (%) 3021 97. 2745 91. 23/35 93. 1760 a 1403 88. 1192 85. mnooouo Flow (cfs) 125 108 90.3 69.6 57.4 50.0 Mr. D. Thompson . -2- November 11, 1997 Unit 1 (continued) Generator Type — Horizontal Synchronous Generator Rating - 3000 KW (Nominal) Speed a 600 rpm Voltage - 4160 V Temperature Rise - 80°C over 40°C Ambient Power Factor _ 0.90 Excitation - Brushless Unit 2 Same as described in our letter of November 5, 1997. Our budgetary price for the above equipment is as follows: Turbines, Generators, HPU's and controls/switchgear - US$ 1,519,000 Prices are F.O.B. Ketchikan, Alaska and include any applicable import duties. Delivery for the proposed equipment is approximately 11 months after contract award. The controls/switchgear will have full manual and automatic operation capability. Station service equipment and main power transformer are not included. Should you have any questions or require additional information, please contact me at: Telephone: (973) 403-8210 FAX No.: (973) 403-7914 Very truly yours, BOUVIER HYDROPOWER, INC. Mark S. Barandy cc Mr. W. Benning; BHP Date To From lo. of pages Fax November 18, 1997 WESCORP Mr. Don Thompson Phone Fax 206 361-8990 Edy O. Sennhauser Phone (415) 441-7230 Fax (415) 441-8868 15 (including this one) Ketchikan Public Utilities Your Oct. 29, 1997 Fax SULZER Technology Corporation Sulzer USA Inc. 1255 Post Street, Suite 946 San Francisco, CA 94109 For your projects we recommend Compact Turbines in each case. The corresponding data are listed on the attachments. Unfortunately, we do not yet have a dimension sketch for the 6-jet Pelton turbine. Scope of Supply e 1x Compact Turbine with the following sub-assemblies: stainless steel runner assembly distributor assembly spiral case and stay ring draft tube elbow and liner e 1x horizontal synchronous generator e 1x hydraulic pumping unit Delivery 12 months after award of contract. Please note that these are Compact Turbines and, therefore, the turbine would be shipped to site with the generator completely assembled except for the draft tube. SULZER Technology Corporation Page 2 of 2 /November 18, 1997 Budget Price Budget prices are for equipment delivered fob project site. Local taxes and fees are not included. Field service (Supervisor, commissioning and start-up) are estimated to be $ 18,000 per unit for any of the options. Electrical Package Sulzer Hydro can supply electrical packages to complete the water to wire supply for each project. If each unit is in a separate powerhouse then the cost for each powerhouse would be about $ 300,000. If the units are all within a single powerhouse then the package costs would be about $ 450,000 for Whitman and $ 375,000 for Lake Connell. The supply would include 5 KV metalclad switchgear line-up and turbine/generator controls for automatic operation of an unmanned plant. We shall be happy to provide you with any further information which you may require. Regards. ITEM WHITMAN LAKE ul WHITMAN LAKE v2 LAKE CONNELL ul LAKE CONNELL u2 CARLANNA LAKE Net head (ft) | 330 350 195 205 450 Discharge 150 55 130 100 40 . (cfs) Turbine Compact Compact Compact Compact Compact 6-jet Compact Francis Francis Francis Francis Francis Pelton Runner 781 477 781 720 663 659 diameter (mm) Speed (rpm) 900 1200 900 900 900 a Turbine 3926 1473 4315 1970 1580 1360 output (kW) Generator Synchronous Synchronous Synchronous Synchronous Synchronous Induction Voltage (V) 4160 4160 4160 4160 4160 4160 Output (kW) 3800 1400 4200 1900 1500 1300 Speed (rpm) 900 1200 900 900 900 720 Budget Price |$ 762,850.- $ 463,600.- $ 762,850.- $ 496,500.- $ 474,200.- $ 587,700.- 11/18/97 sch -3> a3 3 STLNES inc. Pee2<0 Fax Message Gilbert Gilkes & Gordon Ltd. Canal Iron Works T k 0 WESCORP Kendal Cumbria Attention of © 9M: Don Thor-pson England LA9 7BZ From Maanperrss Fax : 01539 732110 Tel : 01539 720028 Far Number : 00 1 28] $84 6£77 (Interuational +44 1539) Date : 25 November, 1997 E-mail: chris@gilkes.com Sheet 1 of : 3 web site: http//www.pilkesu-aet.com Telefax FO. a0 SUBJECT : Request for Budgetary Price Qusutions for KPU Ketchikan, Alaska Dear Don, We are pleased to supply che following budget y ‘res in response to your fax enquiry sent to Mr David Priestley of Gilkes Inc. USA We have provided prices for both Francis Turbines etd Turgo Impulse Turbines for all three projects for your consideration. In general the Turgo Imoulse Turbine equipment prices are higher than the Francis prices. The price difference varies on each site option due to differences in turbine p:ices for the curbines required. To compensate for the higher turbine cost the Terge cffers cther important technical and financial advantages aver Francis turbines on project civ sos!* and running costs. The other important technicai and financial advantages offered by the Turgo Impulse turbine are .- a) The Turgo does not require a surce :¢er incorporating in the penstock pipeline design to accommodate turbine pressurs surges Being an Impulse type turbine the Turgo does not preduce sufficient surz= pressures to necessitate this feature b) The Turgo is more capable in walutsi .g clectrical supply frequency stability dunng load changes than a Franc's because fas speed governing is possible by regulation of the jet dedlector mechanism withovi ‘cducing any oressure surge in the penstock ©) The Turgo does no: have close rnnb.y surfaces round :he runner periphery as a Francis dees so is able to hancle avasive -vater without undue wear taking place a) The Turgo is a rugged machine spec ‘tically designed tw provide reliable trouble Tee Operation withour the need of Feaien: maintenance on projects which cperate with abrasive water ec er Being an Impulse Turvine desig. the Turo Lmpulse turbine do not suffer from cavitation wear as a Francis turbine does @1 am GILKES INC. 23 as revs SOF 142300 PRON GILEEPT WiLnes 2 { To P2306 NIP/T$522,3 & 4 page > 21 November 1997 f) Turgo Impulse turbines de net ha-e 2 imit on the minimum opcrable flow rate a3 a Francis Turbine does If these turbine yenerator sets are required to ze! with speed governing to assist in maintaining electrical supply frequency and are “quired iu up- ci a wide flow range thea the Turgo Impulse turbine has much co offer If the supply warm, vertalas abrasives then they offer considerable advartages over Francis Turbines The scope of equipment we have included in the following package prices is - Francis and Turgo Impulse Turbir > Qari ns. Maun Inlet Valves with Faul-sale tu close operators. Electronic Speed Govermng Equipmen: Hydraulic Control Module Systems 4.16kV Synchronous Generators Lubricating Oil Systems Electrical Control & Switch-gear Pa-els Expon Packing USA Import Duty Sea-freigh: to USA interaatiora! «ap. 4 sohage is at the outgoing terminals of the The electrical termination point of the above ; :, Tracsformers oc any other outgoing clectncal Swiichboards, please note we have not inciudes! S: items, We submit the following Turbine Generazor packazes fur the three projects requested :- Whitman Lake Gilkes Ref. 13522 Whitman Lake Unit 1 Number of Units 2 each for L150 cfs = 300 cfs total. 2 Gilkes 700G19¢ Francis Turbire, 3640 kW Syachronous Generator Packages — 2,090,0)0.00 USD 2 Gukes 38HCTIT/J Turgo Turbine, 3360 KW S.-chrcnous Generator Packages = 2,890,000.C0 USD Whitman Lake Unit 2 Number of Units 1 1 Gilkes $00G150 Francis Turbine, 1400 kW Synchronous Generator Package 640,000.90 USD a —_— —_—— ~ 765,000.0) USD 1 Gikes 2SHCTIT/J Turgo Turbine, 1285 kW Syr brencus Generator Package Whitman Lake Alternative to Unit I Nusaber of Units 2 each for 125 cfs = 250 cfs total. 2 Gilkes 760G190 Francis Turbine. 308C xW Sync*ranous Generator Packages = 2.010,000.00 USD 2 Gilxes 78HCTIT'J Turgo Turbine, 2720 KW S,ach uous Generator Packages 2,828,000 0) USD S-97 89:62 AM GILKES INC. 2815546577 esha 997 14:5 FROM GILBERT oiiye: eae adoes TO GILEES [her P.O4 NIP'T3522,3&4 Peec3 2. November 1997 Lake Connell Gilkes Ref. T3523 Lake Connell Unit J Number of Units 1 1 Gilkes 675G270 Francis Turbine, 1870 kW S: act or.cus Generator Package 805,000.00 USD 1 Gilkes 43HCTIT/S Turgo Turbine, 1710 kW Synchronous Generatur Package = -1.519,000.00 USD Lake Connell Alternative Alternative Unit 1 Number of Units 1 i Gilkes 625G276 Francis Turbine, 1520 kW Syornry ious Generator Package 726,590.00 USD 1 Gikes 38HCTIT,J Turgo Turbine, 1410 kW Somchrenous Generator Package i, ]05,090.C0 USD Calanna Lake Gi 3824 Calanna Lake Unit 1 Number of Units 1 2 Gilkes 45¢Gi30 Francis Turbine, 1310 kW S-ncironaus Generator Package 657.000.00 LSD 1 Gilkes 22 SHCUILYS Lurgo Turbine, 1216 kW Synchrencus Generator Package 706,000.09 USD For Whitman Lake we hope that we have inierprsiec sour requirements curecily as in your enquiry the number of units stated is 2 with a design max discharge as 150 cfs. We have offered two units each capable of passing 150 cis for Umit | and 2 two units each capable of passing 125 cfs for Alternative to Unit | We hope that the above prices provide everythin you require but if you require any clarification or modification please contact us Best Regards, han Tan Porter, Hydro & Power Systems Division. Gilbert Gilkes & Gorcon Lid TOTAL P. VOITH HYDRO vot yao, ne POWER GENERATION Telephone: 509 255 6398 Teletax: 509 255 6399 Voith Hyaro, Inc., 203 N. Kelsea Court. Liberty Lake, Washington 9901 Email: pymegrath@vorthyork.com November 11, 1997 Wescorp 18021 15" Ave. N.E., Suite 101 Shoreline, WA 98155 Attn: Mr. Don Thompson Dear Mr. Thompson, Thank you for your inquiry, dated October 31, 1997 regarding three projects being studied for Ketchikan Public Utilities. Enclosed are some brochures describing the range of impulse and Francis turbines we can offer for small hydro applications. These would be considered our “standard” designs for such smaller turbines. The brochures will aid you in getting a feel for the physical size of the machines you are interested in, as well as the nominal performance of the machines. Budgetary pricing for a complete water-to-wire package including turbine, generator, exciter, governor, unit controls, switchgear, and inlet valve, would be as follows: Whitman Lake - Unit #1, Horizontal Francis, approx. 4 MW at 720 RPM: $1,400,000.00 Unit #2, Horizontal Francis, approx. 1.5 MW at 720 RPM: $700,000.00 Unit #3, Horizontal Francis, approx. 4.5 MW at 720 RPM: . $1,400,000.00 Lake Connell - Unit #1, Horizontal Francis, approx. 2 MW at 720 RPM: $800,000.00 Unit #2, Horizontal Francis, approx. 1.7 MW at 720 RPM: $700,000.00 Carlanna Lake - Unit #1, Horizontal Francis, approx. 1.4 MW at 1800 RPM: $700,000.00 The above prices are exclusive of any applicable taxes or duties, are FOB Ketchikan, and do not include installation/commissioning. VOITH GROUP OF COMPANIES —~ Kvaerner Hydro Power November 5, 1997 Mr. Don Thompson Wescorp 18021 15" Ave. NE, Suite 101 Shoreline, WA 98155 Subject: Whitman Lake Project Lake Connell Project Carianna Lake Project Dear Mr. Thompson: Please find below our reply to your telefax dated 29-Oct-97. Due to our current workload, the information is very limited and preliminary, however should the project go ahead we would be very interested to have the opportunity to put together a firm proposal. The following is for a water-to-wire equipment package, based on the head and flow given in your fax. The water-to-wire package includes supply of turbine, turbine shut-off valve, hydraulic power unit, generator, and switchgear/controls: Whitman Lake Project Unit 1: horizontal Francis; 3.9 MW; 720 rpm Unit 2: horizontal Francis; 1.5 MW; 1200 rpm Unit 3: horizontal Francis; 4.4 MW; 720 rpm Preliminary budget price = USD$ 3,000,000. Lake Connell Project Unit 1: horizontal Francis; 2 MW; 720 rpm Unit 2: horizontal Francis; 1.6 MW; 900 rpm Preliminary budget price = USD$ 1,500,000. Carianna Lake Project Unit 1: horizontal 2-jet Pelton; 1.4 MW; 360 rpm Preliminary budget price = USD$ 1,250,000. This estimate is very preliminary and additional work is required to come up with a more accurate cost. . KVAERNER Kvaerner Hydro Power Inc 49 Stevenson Street Suite 1075 San Francisco, CA 94105 USA