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HomeMy WebLinkAbout5 - Proposed ProjectDRAFT Application for Preliminary Permit – Silver Lake Project Exhibit 1 – Description of Proposed Project Copper Valley Electric Association 7/22/2009 © 2009 Copper Valley Electric Association, exclusive of U.S. government maps 1 APPLICATION FOR PRELIMINARY PERMIT SILVER LAKE PROJECT COPPER VALLEY ELECTRIC ASSSOCIATION EXHIBIT 1 – DESCRIPTION OF PROPOSED PROJECT 1. PROJECT LOCATION Silver Lake is situated in a glacially formed bowl surrounded by steep mountains on three sides approximately 15 miles southwest of Valdez, Alaska. The eastern-most section of the lake is bordered by a low lying delta. The lake is approximately 3 miles long, has a maximum width of about 0.7 miles. The natural normal pool elevation of Silver Lake is El. 306 with a surface area of about 978 acres. The outlet of Silver Lake forms the Duck River which flows westerly for about 1.5 miles where it discharges into the lagoon at the head of Galena Bay. The upper portion of the Duck River flows through steep rock canyons and has 5 waterfalls of at least 10- feet in height. The highest waterfall is approximately 60-feet-high located about 3000 feet upstream of the lagoon. This waterfall has been considered by many to be the first impassible fish barrier on the Duck River.1 See Exhibit 3.1 Project Location Map. 2. PROPOSED PROJECT The primary purpose of this Application for Preliminary Permit is to secure the right to investigate the power potential at Silver Lake and determine the best adapted use of that power potential in the geographic area. The project study area is shown on Exhibits 1.1 and 1.2. Detailed maps showing the project boundary are provided in EXHIBIT 3 – PROJECT MAPS AND PHOTOGRAPHS: Exhibit 3.1 Location Map Exhibit 3.2 Project Map 2.1 Project Description FEATURE DESCRIPTION 1.A Dam 1.A.1 – Dam 125-foot high roller-compacted concrete 1.A.2 – Spillway Non-gated overflow on the southwest abutement 1. B Water Conveyances 1.B.1 – Intake Conventional intake south of the Silver Lake outlet 1.B.2 – Penstock 9-foot diameter buried steel penstock / 6,000-feet-long 1.C Powerhouse 1 Allison Lake Reconnaissance Study, Silver Lake Appendix B, prepared for the State of Alaska and the Al aska Energy Authority. September 1992. DRAFT Application for Preliminary Permit – Silver Lake Project Exhibit 1 – Description of Proposed Project Copper Valley Electric Association 7/22/2009 © 2009 Copper Valley Electric Association, exclusive of U.S. government maps 2 FEATURE DESCRIPTION 1.C.1 Powerhouse Located 3000 feet upstream from the mouth of the Duck River at low tide and located at the foot of the last downstream major natural falls at elevation 65 feet. Powerhouse contains three Francis turbines, each with a total rated head of 353 feet. Rated installed capacity of the powerhouse would be 15 MW. 1.C.2 Tailrace Open channel 1.D – Other Project Structures 1.D.1 Ecological return flow facility An ecological return flow facility would be provided at the base of the dam for resident species within Duck River. The powerhouse will be located above salmon spawning areas and will be operated as required to accommodate the respective life cycles thereof below the powerhouse. 2. Reservoir – Silver Lake 2.A – Surface Area - raised 1678 acres 2.B – Storage capacity - raised 165,200 acre-feet 2.C – Normal max surface elevation - raised 425 feet 3. Transmission Transmission to Soloman Gulch would be via 25 miles of overhead transmission line. 4. Generating Equipment 4.A – Estimated Average Energy 44.8 GWh/year 4.B – Number of generating units Three Francis turbines, each with a total head of 353 feet. 4.C – Turbine rating for each unit 3 units @ 5 MW each 4.D – Generator rating for each unit 3 units @ 5 MW each 4.E – Single capacity rating for each unit 3 units @ 5 MW each 4.F – Existing and/or proposed 3 proposed units; No existing units 4.G – Hydraulic head Design head =~ 353 feet 5. List of Federal Lands within Project Boundary None Site Access Existing access is by water or air only. A dock would be located on the south bank of Galena Bay for loading and unloading people and supplies from a boat. Access would be provided by the construction of a permanent access road to the powerhouse and dam . During operation, the project would be operated remotely from Valdez. Other Structures Switchyard and appurtenant facilities Housing would be provided for power plant operators Staging areas for construction and substation facilities DRAFT Application for Preliminary Permit – Silver Lake Project Exhibit 1 – Description of Proposed Project Copper Valley Electric Association 7/22/2009 © 2009 Copper Valley Electric Association, exclusive of U.S. government maps 3 3. PROJECT TRANSMISSION Transmission to Soloman Gulch would be via 25 miles of overhead transmission line. 4. TOTAL ESTIMATED ENERGY PRODUCTION The estimated annual energy production under average water conditions is 44.8 GWh. 5. LANDS PROPOSED TO BE OCCUPIED BY THE PROPOSED PROJECT The following lands are indicated on the maps in Exhibit 3 of this Application for Preliminary Permit. Lands owned by the Chugach Alaska Corporation (CAC) and Tatitlek Native Corporation (TNC) as indicated below. PROJECT SECTION TOWNSHIP RANGE OWNERSHIP FACILITIES Reservoir S31 10S 7W CAC Reservoir S32 10S 7W CAC Reservoir S3 11S 7W CAC Reservoir S4 11S 7W CAC Reservoir S5 11S 7W CAC Reservoir S6 11S 7W CAC Reservoir S9 11S 7W CAC Reservoir S10 11S 7W CAC Reservoir S11 11S 7W CAC Reservoir S14 11S 7W CAC Reservoir S15 11S 7W CAC Dam, reservoir, intake, access road, penstock S6 11S 7W CAC Access roads, dock S11 11S 6W TNC Access road S12 11S 6W TNC Access road, penstock, powerhouse & related facilities S1 11S 6W TNC, CAC 6. DEVELOPMENT OF REGIONAL WATER RESOURCES CVEA would use power generated by the proposed Silver Lake Project to replace its current dependency on diesel generation. Discuss other geographic areas that could be served. DRAFT Application for Preliminary Permit – Silver Lake Project Exhibit 1 – Description of Proposed Project Copper Valley Electric Association 7/22/2009 © 2009 Copper Valley Electric Association, exclusive of U.S. government maps 4 EXHIBIT 1 PROJECT MAPS Exhibit 1.1 Project Location Map Exhibit 1.2 Study Area Silver Lake Project PROJECT LOCATION MAP Exhibit 1.1 PROJECT LOCATION Project Area Silver Lake Project STUDY AREA Exhibit 1.2 110 Mile Map is based on USGS Cordova (D-7) ALASKA. Contours are in 100 foot intervals Legend Chugach Alaska Corp. Land Tatitlek Native Corp. Land Dock Site Study Boundary Intake Powerhouse Dam Access Road Buried Penstock