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HomeMy WebLinkAboutAPPENDIX 2 - Adak Hydropower Feasibility and Conceptual design - appendices 2 Hatch Feb. 2013 report TDX Power 615 E. 82nd Avenue, Suite 200 Anchorage AK 99518 Reconnaissance Study - Final Report For TDX Power - Adak Reconnaissance Study H343115-0000-00-236-0001 Rev. 1 02/06/2013 TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 1 Project Report 02/06/2013 TDX Power Adak Reconnaissance Study Distribution Martin Miller, TDX Power Final Report Table of Contents Terms, Acronyms, and Abbreviations ...................................................................................................... 3  1. Introduction ........................................................................................................................................... 4  1.1 Community Overview .................................................................................................................... 4  1.1.1 Location: .............................................................................................................................. 4  1.1.2 History ................................................................................................................................. 4  1.1.3 Military Uses of Adak .......................................................................................................... 5  1.1.4 Climate: ............................................................................................................................... 6  1.1.5 Land Ownership: ................................................................................................................. 6  1.1.6 Facilities: ............................................................................................................................. 7  1.2 Previous Hydroelectric Studies ..................................................................................................... 7  2. Geography ............................................................................................................................................. 8  3. Geology ................................................................................................................................................. 9  4. Site Control ........................................................................................................................................... 9  5. Environmental and Aquatic Resources ........................................................................................... 10  6. Existing Infrastructure ....................................................................................................................... 11  6.1 Existing Generation and Demand ............................................................................................... 11  6.2 Water System ............................................................................................................................. 12  7. Water Use ............................................................................................................................................ 12  8. Hydrology ............................................................................................................................................ 14  9. Project Options and Initial Evaluation .............................................................................................. 18  10. Lake Bonnie Rose to Mitt Lake Project Analysis ............................................................................ 20  10.1 Description .................................................................................................................................. 20  10.2 Analysis ....................................................................................................................................... 21  10.3 Cost Estimate .............................................................................................................................. 23  10.4 Economic Value .......................................................................................................................... 24  11. Existing PRV Project .......................................................................................................................... 26  12. Recommendations ............................................................................................................................. 28  TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 2 13. References .......................................................................................................................................... 29  Table 1 - Lake Summary ............................................................................................................................... 8  Table 2 - Existing Applied, Permitted, or Certificated Water Rights, Lake Bonnie Rose and De Marie ..... 12  Table 3 - USGS Stream Gauge Summary .................................................................................................. 14  Table 4 - Rainfall Data ................................................................................................................................ 14  Table 5 - Project Stream Flow Derivation ................................................................................................... 17  Table 6 - Derived Monthly Average Stream Flows (cfs) for Each Project Location .................................... 17  Table 7 - Project Options and Analysis Matrix ............................................................................................ 18  Table 8 - Mitt Lake Project Cost Estimate ................................................................................................... 24  Table 9 - Mitt Lake Project Performance Summary (Town load only) ........................................................ 25  Table 10 - Mitt Lake Project Performance Summary (Town and Processor load) ..................................... 25  Table 11 - Existing PRV Cost Estimate ...................................................................................................... 26  Table 12 - Existing PRV Project Performance Summary (Town load only) ................................................ 27  Figure 1 - Adak Location ............................................................................................................................... 6  Figure 2 - Adak Demand Profile .................................................................................................................. 11  Figure 3 - USGS Monthly Average Stream Flow Chart .............................................................................. 16  Figure 4 - Lake Bonnie Rose Hydrograph .................................................................................................. 20  Figure 5 - Lake Bonnie Rose Flow Duration Curve .................................................................................... 21  Figure 6 - Mitt Lake Project Operation Chart without Environmental Flow Restrictions ............................. 22  Figure 7 - Mitt Lake Project Operation Chart with Environmental Flow Restrictions .................................. 22  Attachments Plate 1 - Location Map Plate 2 - Site Map Plate 3 - Project Map TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 3 Terms, Acronyms, and Abbreviations TERM MEANING ADNR Alaska Department of Natural Resources AEA Alaska Energy Authority Avg Average BTU British Thermal Unit cfs Cubic feet per second cyd Cubic yards Dia Diameter DIP Ductile Iron Pipe ea Each FERC Federal Energy Regulatory Commission gal Gallon gpd Gallons per day gpm Gallons per minute HDPE High density polyethylene ID Inside diameter kVA Kilo Volt-Amps kW Kilo Watt (1000 Watts) kWh Kilo Watt-hours lb Pound mgd Million gallons per day mi Mile mmBTU 1 million BTU's mo Month O&M Operation and Maintenance OD Outside Diameter SDR Sidewall Diameter Ratio sq ft Square feet sq mi Square miles sq yd Square yard TDX Tanadgusix Corporation TDX Power Subsidiary of TDX, owner and operator of regulated utilities in Sand Point, Manley, Adak, and Prudhoe Bay. USGS United States Geological Survey TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 4 1. Introduction TDX Power is evaluating renewable energy options for the city of Adak, Alaska and has tasked Hatch with an update to the July, 2011 Adak Reconnaissance Study, Final Report. The general purpose of this report update is to include recently collected demand information in the comparative analysis between the different potential hydroelectric developments, perform an initial cost estimate for the recommended project(s), and incorporate improved mapping that was used to identify the different alternatives into the report. It has been found that there are numerous hydroelectric generation possibilities on the island of Adak. This report identifies the different potential projects and performs a high level comparison of the options. While this report includes a brief analysis of the most likely option, most of the options should be vetted further with site visits and additional data collection and analysis before making a recommendation for future development. 1.1 Community Overview Current Population: 326 (2010 U.S. Census Population) Pronunciation/Other Names: (A-dack); formerly Adak Station Incorporation Type: 2nd Class City Borough Located In: Unorganized School District: Aleutian Region Schools Regional Native Corporation: Aleut Corporation The community incorporated as a second-class city in April 2001. 1.1.1 Location: Adak is the southern-most community in Alaska, on the latitude of Vancouver Island in Canada. The former Navy Air Facility Adak is located off the Alaskan mainland near the center of the Aleutian chain, approximately 1,200 miles west-southwest of Anchorage, Alaska. Flight time to Anchorage is three hours. Adak Island’s coordinates are latitude 51°53’0" N, at longitude 176° 38’46" W. The Bering Sea surrounds the island to the north and the Pacific Ocean to the south. Adak is located in the Aleutian Islands Recording District. The area encompasses 122.4 sq. miles of land and 4.9 sq. miles of water. 1.1.2 History The first inhabitants of Adak Island were the Aleuts. Archaeological evidence reflects occupation as early as 9,000 years ago. The Aleuts hunted whales, seals, otters and sea lions, as well as island birds, and fished Adak’s freshwater streams and the surrounding seas. They lived in large, communal, subterranean structures of grass and earth built over driftwood or whalebone frames. The Aleuts developed technologies such as sophisticated kayaks and waterproof clothing to deal with the cool marine environment. Aleut settlements were often located in coves along freshwater streams. Remnants of prehistoric Aleut settlements remain on Adak today. Russians first visited the Aleutian Islands in the early 1740s and were trading with the Aleuts by the 1750s. As recently as 1827, Adak was a busy trading settlement with a population of 193 Aleuts. By 1830, Russian settlers had occupied Adak and relocated the Aleuts to Russian settlements in Kodiak, the Pribilof Islands, and Sitka. Adak Island became part of the Alaska Territory, which was subsequently purchased from Russia by the United States in 1867. Even after the permanent Aleut villages were abandoned, seasonal and subsistence use of the island continued. By 1910, over hunting by outsiders had nearly depleted the once- abundant sea otter and fur seal populations. In 1913, Adak Island was included in the 2.9- TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 5 million-acre Aleutian Islands National Wildlife Refuge (renamed the Alaska Maritime National Wildlife Refuge in 1980) established by the President. This refuge was set aside as a preserve and breeding ground for native birds and fur-bearing animals and as an important fisheries habitat. Seasonal and subsistence use of the island by the Aleuts continued up until the time of World War II, when Aleuts in the island chain were evacuated to internment camps. 1.1.3 Military Uses of Adak Since the early 1940s, the northern half of Adak Island has been used for military operations. During World War II, Adak Island became the site of a military base operated by the Army Air Corps for defensive action against Japanese forces occupying Attu and Kiska Islands in the Aleutian chain. In the spring of 1944, Adak’s population included at least 32,000 military personnel. In preparation for a major offensive on the Japanese-occupied islands of Kiska and Attu, as many of 90,000 troops on ship or shore were mobilized to the Aleutian arena. Since the war, the military presence on Adak has fluctuated, depending on United States defense policy and federal appropriations, and has generally not exceeded 6,000 persons. After the war, the base was transferred to the U.S. Air Force (renamed Davis Air Force Base) and, according to Army Corps of Engineers records, encompassed all of Adak Island. The U.S. Air Force withdrew from Adak in 1950, and the Navy assumed all facilities on Adak Island. In 1953, only 15 officers and fewer than 200 enlisted men were assigned to the base. In 1959, Public Land Order No. 1949 withdrew land described as representing approximately 61,000 acres (the resurveyed land mass is 79,200 acres) of Adak Island (approximately the northern half) for use by the Navy. By 1966, military and civilian personnel totalled almost 1,000, a number that stayed fairly steady through the 1970s. By 1981, the population had doubled by 2,000. In 1984, the Adak Naval Station was renamed Naval Air Station (NAS) Adak. By 1990, over 5,000 people were at the base, almost 3,000 of whom were military, the remainder composed of military dependents and civilian employees. In 1994, NAS Adak was designated as Naval Air Facility (NAF) Adak. As of February 1996, following military draw down and closure of Naval Security Guard Activity (NSGA), approximately 500 military and 50 civilian personnel were stationed on Adak. Subsequent to its listing under Base Realignment and Closure in July 1995, the military mission at Adak was ended on March 31, 1997. The Aleut Corporation purchased Adak's facilities under a land transfer agreement with the Department of the Interior and the U.S. Navy/Department of Defense. This agreement was finalized in March, 2004. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 6 Figure 1 - Adak Location 1.1.4 Climate: The maritime climate on Adak is characterized by persistently overcast skies, high winds, and frequent, often violent, cyclonic storms originating in the northern Pacific Ocean and Bering Sea. Weather can be localized, with fog, low ceilings, precipitation, and clear weather all occurring within a distance of a few miles. Storms can occur during any season, although the most frequent and severe storms occur during the winter. Mean annual precipitation for Adak Island is about 66 inches, most of which falls as rain. Average monthly precipitation varies from a low of 3 inches in June and July to a high of 7 to 8 inches in November and December. Snowfall averages over 100 inches per year. Because of the relatively warm temperatures, snow rarely exceeds 1 to 2 feet in depth and is concentrated in the mountains. Mean monthly temperatures vary from a low of 32.9° F in February to a high of 51.3° in August. The highest temperature recorded on Adak is 75° F (August 1956), and the lowest temperature is 3 degrees F, recorded in January 1963 and February 1964. 1.1.5 Land Ownership: A land exchange between Aleut Corp., the U.S. Navy, and the Department of the Interior has transferred most of the naval facilities to the Aleut Corporation. A portion of the island remains within the national Maritime National Wildlife Refuge, managed by the U.S. Fish & Wildlife Service. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 7 1.1.6 Facilities: After World War II, the U.S. Navy developed facilities and recreation opportunities at Adak. A movie theater, roller skating rink, swimming pools, ski lodge, bowling alleys, skeet range, auto hobby shop, photo lab, and racquetball and tennis courts were developed. An $18-million hospital was built in 1990. As of 2009, all of these facilities are closed. Substantially all of the infrastructure and facilities on Adak are owned by Aleut Corporation, who is currently developing Adak as a commercial center via their subsidiary companies. The former base has two areas with extensive development. The first is the "downtown" area of Adak, where NAF was located and which includes the airfield, port facilities, landfills, sewage treatment facilities, light industrial, administration, commercial, recreational, and residential areas. The second main developed area, formerly used by NSGA, includes the northern part of the island and areas around Clam Lagoon. The NSGA area is no longer used. Water is derived from Lake Bonnie Rose, Lake De Marie, and Nurses Creek, stored in any of the seven water tanks throughout the community, and piped to facilities and housing units. The wastewater treatment system discharges through a marine outfall line to Kuluk Bay. Husky Road landfill is a class III permitted landfill. Adak provides a fueling port and crew transfer facility for fishing fleets, and an airport, docks, housing facilities, restaurant, grocery store, and ship supply store are available. The seafood processing facility can process about 500,000 pounds of fish per day. In 2010, two residents held commercial fishing permits. Adak Airport is a State of Alaska owned & maintained certificated airport. It has two asphalt paved runways; one measures 7,790' long by 200' wide, and the other runway measures 7,605' by 200' wide. Alaska Airlines operates passenger and cargo jet service. There are three deep water docks and fueling facilities. In 2009, the city was in the process of expanding the Sweeper Cove small boat harbor to include new breakwaters, a 315' dock, and new moorage floats. Adak has approximately 16 miles of paved roads, as well as gravel and dirt roads. 1.2 Previous Hydroelectric Studies A previous study by Ebasco Services Inc. (Ebasco, 1980) looked at four sites:  Sites 1 and 2 - run of river sites located on the west side of Mt. Moffett (not included in this report).  Site 3 - Lake Bonnie Rose to Lake De Marie.  Site 4 - Lake Betty to tidewater. The reported states "Sites does not have economic hydropower development potential." It also noted that there were environmental concerns with salmon migration in streams with hydropower potential. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 8 Information provided for sites 3 and 4 include the following: Site 3 4 Intake Location Lake Bonnie Rose Lake Betty Powerhouse Location Lake De Marie Tidewater Average Annual Streamflow (cfs) 14.8 12.8 Total Head (feet) 200 200 Net Head (feet) 180 180 Installed Capacity (kW) 192 166 No other studies investigating hydroelectric potential in Adak have been found. 2. Geography Adak Island was formed by extreme geologic events, including the tectonic collision of large sections (plates) of the earth’s crust and resulting volcanic eruptions. Advancing and receding glaciers, frequent rainfall, and high winds have shaped Adak Island into a dramatic landscape of hills, valleys, cliffs, and floodplains. Very few areas of the island are flat, and grading to create flat areas could not be done easily. The highest point on Adak Island is Mt. Moffett (elevation approximately 3,875 feet). Some coastal cliffs on the island rise 2,500 feet above sea level. Topographic data was obtained from CAD drawing files provided by TDX. The files were developed by PND Engineers and contained 20' interval contours for areas located within the naval base boundary. For areas outside the PND mapping area topographic data from the Shuttle Radar Topography Mission and USGS was used along with 1:50,000 scale U.S. Defense Mapping Agency maps of Adak (updated in 1974) containing 20 meter interval contour data. Plate 1 at the end of this document shows the USGS map for the island. The upland topography of Adak is typical of the Aleutian Islands with rolling, steep terrain, volcanic features, and shallow, but often sharp crested, stream valleys. The vegetation primarily consists of grass with no trees or shrubs. Some exposed bedrock and areas of eroding volcanic soils can be found. Several large lakes are formed in what are likely glacial carved depressions. These are primary candidates for hydropower development. The table below summarizes the lakes in the vicinity of the developed area of Adak. Table 1 - Lake Summary Sources Elevation, ft Basin Area (at outlet), sq mi Surface Area, acres Lake Bonnie Rose 739 1.55 139.2 Lake De Marie 234 3.59 86.7 Heart Lake 153 4.18 36.4 Lake Betty 159 4.43 136.6 Lake Leone 113 0.88 78.3 Mitt Lake 45 0.78 12.4 TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 9 3. Geology Adak Island was created during the last 60 million years by a complex set of geologic processes resulting from the collision of the North American and Pacific crustal plates. The resulting rock sequences consist primarily of volcanic rocks with some sedimentary rock. A relatively thin layer of unconsolidated material (generally less than 10 feet think) covers the entire island. Only the downtown area is known to have a thick sequence of unconsolidated material (greater than 100 feet). The northern region of Adak is dominated by the remnants of three volcanoes. Throughout most of the project area, a 2 to 3 meter thick mantle of tephra blankets other surficial deposits and bedrock. A 1995 geologic map for the area indicates bedrock and tephra deposits in the area around Lake Bonnie Rose and Mitt Lake. The following is reported about the surficial deposits and bedrock in Adak (Waythomas, 1995): Tephra deposits are usually 1.5 to 3.0 m thick and consist of thin beds of fine grained (mostly silt and clay size particles) ash and 3 to 5 beds of lapilli-sized (2-64 rnm) tephra. Locally interbedded with peat. Many of the ash layers are weathered to clay. Somewhat porous, but permeability is limited by fine particle size. Lapilli beds are more porous and permeable than the fine grained tephra layers. Locally water bearing, especially in low- lying areas. Areas of bedrock may include minor amounts of talus and colluviurn. In areas away from Mount Moffett and Mount Adagdak, most of the bedrock consists of Finger Bay Volcanics (Coats, 1956). These rocks are extensively fractured and faulted, and locally exhibit some weathering. Zones of bedrock where fracture density is high may be porous and permeable and may be water bearing. The hydroelectric projects envisioned in this report will require roads or trails to the powerhouse and intake locations. Pipelines can be located outside road access and laid on supports or directly on the ground or buried. Construction equipment use may be limited where pipelines are located off road in Tephra deposits without a solid base to support the equipment. Some difficulties may also be encountered burying pipelines within road footprints due to existing infrastructure. The cost estimate assumes no difference in cost for pipelines located off road versus pipelines buried within the roadway. 4. Site Control Land ownership and use has not been investigated as part of this study. All of the projects considered in this report are located outside the US Fish and Wildlife Refuge boundary and are presumably entirely owned by the Aleut Corporation or the City of Adak, both with an interest in lowering the cost of electricity generation in order to improve economic development and sustainability for Adak. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 10 5. Environmental and Aquatic Resources This report does not address in any detail the potential environmental impacts of the projects considered. A review of the ADF&G's catalog of anadromous habitat indicates that all of the project options are located on streams that have anadromous fish in their lower reaches. Approximate habitat locations based off the catalog are as follows. It is possible that the catalog is not entirely accurate with some reaches shorter or longer than stated.  Lake Bonnie Rose - Lake De Marie - Heart Lake drainage: The upper limit of anadromous habitat is estimated at about elevation 100', reach about 1000' long.  Lake Leone: The upper limit of anadromous habitat is estimated at elevation 60', reach about 630' long.  Lake Betty: The upper limit of anadromous habitat is estimated at elevation 30', reach about 2200' long.  Mt Reed Creek: The upper limit of anadromous habitat is estimated at elevation 250', reach about 1300' long (note: average gradient ~20%).  Mt Moffett Creek: The upper limit of anadromous habitat is estimated at elevation 20', reach about 1500' long. Additionally, many of the streams and lakes support resident fresh water species such as Dolly Varden and trout (HDR 2011). The protections for these non-anadromous aquatic resources are evident in the water use reservations for fish passage purposes identified later in this report. The presence of fresh water species found in the lake system, and likely in other streams as well, is the most significant concern for hydroelectric development. All of the potential hydro schemes are run of river projects that bypass natural stream reaches. Additional habitat and instream flow investigations, focused on hydro related impacts, must be undertaken for permitting any of the proposed projects. A potential concern with excavation for installation of pipelines and foundation structures is the presence of contaminated sites and unexploded ordinance. Extensive information regarding site assessment and cleanup activities is available at the environmental cleanup and closure of the former Naval Air Facility, Adak, Alaska website (http://www.adakupdate.com/). Water quality may be a concern in the design of pipe works and intake equipment. A report on the water system (Bristol, 2010) indicates that the water from Lake Bonnie Rose is "aggressive" with a low pH and a high amount of dissolved oxygen. Cathodic protection was strongly recommended for the water system. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 11 6. Existing Infrastructure 6.1 Existing Generation and Demand An updated demand profile consisting of hourly data, for a 12 month period, was provided by TDX for a time span between 2011 and 2012. This profile is based on metering of an operational fish processing plant and, because separate metering was not available for the town, a synthesized town load was developed by TDX. The synthesized profile was created using totalized sales data that was converted to hourly demand using daily load variations measured at the TDX power plant in St. Paul and scaled to Adak’s energy profile. This data is shown in the following figure. Figure 2 - Adak Demand Profile The existing generation equipment consists of oversized, for the current load, caterpillar 3516 diesel generators. TDX Power reports that one new high efficiency unit is being installed that will be sized for the current and expected future demand. Hydroelectric project benefits are evaluated using an operational model. The modeling of the existing diesel generation system ignores efficiency and is simplified to a single performance parameter of 14 kWh/gal. The model also includes a minimum diesel loading of 40 kW but does not include minimum run time, maintenance, and capital replacement costs. Both load cases (Town only, and Town with Processor) are considered in the analysis and presented in this report. 0 100 200 300 400 500 600 700 800 1/1 1/29 2/26 3/25 4/22 5/20 6/17 7/15 8/12 9/9 10/7 11/4 12/2 12/30Demand (kW)Date Adak Daily Average Demand Profile  Average Town  + Icicle Average Town Only TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 12 6.2 Water System Lake Bonnie Rose and Lake De Marie have existing dams at their outlets for collection of water. As indicated in the Design Analysis Report for the water system (Bristol, 2010), the current source of raw water is from Lake Bonnie Rose. The Lake Bonnie Rose dam has a crest elevation of 739' and is a concrete cantilever wall type structure. The outlet works of the existing Lake Bonnie Rose dam consists of a screened inlet in the reservoir connected to a 12" pipe penetration with an invert elevation of 731.25'. Water is conveyed through an existing 10" ductile iron pipeline, circa 1990's (Bristol 2010 and WHPacific, 2012), from Lake Bonnie Rose to a PRV located at elevation 306' and set to 70 psi (PRV-1). There are numerous tanks and PRV's that serve various distribution areas. Water tank capacity on Adak is 3.7 million gals with 1.9 million gallons in use ("A" and "B" tanks). The Adak system operator has reported that the overflow elevation of tanks A and B is 235.8' and 231.9' respectively. 7. Water Use The Alaska Department of Natural Resources (ADNR) Water Resources division manages water rights in Alaska and reports the following existing uses. Table 2 - Existing Applied, Permitted, or Certificated Water Rights, Lake Bonnie Rose and De Marie Month Potable Export - Bonnie Rose Export - Lake De Marie Environmental(a) - Lake Bonnie Rose(b) Environmental(a) - Lake De Marie(c) Jan 1.4 0.8 0.8 5 10 Feb 1.4 0.8 0.8 5 10 Mar 1.4 0.8 0.8 5 9 Apr 1.4 0.8 0.8 5 9 May 1.4 0.8 0.8 4 8 Jun 1.4 0.8 0.8 4 8 Jul 1.4 0.8 0.8 4 8 Aug 1.4 0.8 0.8 4 9 Sep 1.4 0.8 0.8 5 10 Oct 1.4 0.8 0.8 5 11 Nov 1.4 0.8 0.8 5 12 Dec 1.4 0.8 0.8 5 10 Notes: (a) Environmental flows from Lake Bonnie Rose and Lake De Marie exclude flows from Heart Lake. (b) Minimum of 2" over Lake Bonnie Rose spillway also established equal to 3.3 cfs1. (c) Minimum of 2" over Lake De Marie spillway established equal to 14 cfs2. Water rights for potable use by the City of Adak includes both Lake Bonnie Rose and Lake De Marie but the Lake De Marie water collection system is currently not operable. TDX Power reports, based on a discussion with the City of Adak Public Works Director, that water flow at 1 Lake Bonnie Rose Dam Safety Inspection Report indicating spillway width of 14.5' and a coefficient of 3.33. 2 Lake De Marie Dam Safety Inspection Report indicating spillway width of 51.5' and a coefficient of 4. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 13 PRV-1 is about 215 gpm (0.5 cfs). This includes continuous, unmetered overflow at the A- tanks. Actual potable water needs are unknown. Domestic water use is presumed to be 215 gpm in the analysis. Future modifications to the water system suggests construction of a new water treatment plant with design flows of 35 to 70 gpm (Bristol, 2010). Water use with the fish plant online is estimated, by the public works director, to be up to 800 gpm (1.8 cfs). The water system report (Bristol, 2010) indicates there are plans to convert the fish processing service to raw water supply. No information on the timing or future supply source of this use has been obtained and it is not included in the hydropower analysis. The water rights for export aren't fully representative of actual plans for export operations. TDX reports that the export plan is to tap into the existing raw water pipeline above PVR-1 and route approximately 1/2 mile of new 12” HDPE to discharge directly into an ocean vessel. Each vessel can hold 5 million gallons. Estimated fill time is 8 hours (23 cfs). It is noted that the export operation would station one person at the dam during each vessel filling operation to monitor lake level to ensure compliance with the water rights permit. The export operation expects to load one vessel (5 million gal) every 10 days. The export operation includes Lake Betty, with the largest average annual flow, as a potential source for water export. Unused water tank capacity could be used to store water for the export operation as well to reduce instantaneous demand from Lake Bonnie Rose when a vessel is in for filling. The assumed quantity of water used in this analysis for export is the amount of 0.5 mgd as described in the water rights application. In addition to the monthly environmental flows, the water rights include a minimum of 2" of water over the spillway of Lake De Marie, equivalent to 14 cfs, which also effectively establishes environmental flows at the outlet of Lake Bonnie Rose of 6.4 cfs based on the relative basin areas. The analysis of the selected project disregards this criteria and uses the less stringent monthly environmental flows established at Lake Bonnie Rose instead. Environmental flows have the most significant impact on hydroelectric operations. The minimum bypass flows established at the dams, particularly the minimums for overflow at Lake De Marie, significantly curtail the potential water available for hydropower. Additionally, the environmental flows practically eliminate the potential of using the existing dams as storage reservoirs. Environmental flows are excluded from the initial identification of projects and preliminary analysis. However, environmental flows are included in the detailed analysis for the selected project. Additional investigation of flows for fish passage requirements, which can result in changes in the existing environmental flows, will require significant data collection, analysis, and consultation with ADF&G and ADNR. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 14 8. Hydrology Short, steep-gradient streams draining radially from Mt. Moffett, Mt. Adagdak, and other upland areas characterize the surface water hydrology of the northern portion of Adak Island. Perennial flow is maintained by snowmelt in the mountains and seepage from the shallow surficial soils. Numerous lakes and sediment deposits occur along stream courses. The USGS has measured stream flows at two locations on Adak Island in addition to numerous sites on Amchitka, two on Shemya, and one at Cold Bay. The following table summarizes the data for these sites. Table 3 - USGS Stream Gauge Summary No. of Records Basin Area Unit Flow (cfs/mi^2) Station ID Station Name Begin Date End Date Days Years Sq Mi Avg Med 15297610 RUSSELL C NR COLD BAY AK(a) 10/1/1981 6/23/2011 7663 21.0 30.9 8.2 6.7 15297617 SWEEPER C AT ADAK IS AK 10/1/1992 4/22/1996 1300 3.6 1.0 4.1 2.7 15297625 MOFFETT C AT ADAK IS AK 10/1/1993 4/22/1996 935 2.6 4.5 6.0 4.9 15297640 LIMPET C ON AMCHITKA IS AK 11/1/1967 9/30/1972 1796 4.9 1.7 3.1 2.1 15297650 FALLS C ON AMCHITKA IS AK 4/1/1968 2/19/1972 1420 3.9 1.0 2.1 1.6 15297655 CLEVENGER C ON AMCHITKA IS AK 4/1/1968 5/23/1974 2244 6.1 0.3 3.8 2.7 15297680 BRIDGE C ON AMCHITKA IS AK 11/1/1967 8/28/1974 2493 6.8 3.0 1.5 0.8 15297690 WHITE ALICE C ON AMCHITKA IS AK 4/1/1968 8/27/1974 2340 6.4 0.8 2.8 2.0 15297767 LK C AT SHEMYA AFB AK 11/21/1970 11/30/1972 741 2.0 1.0 1.8 1.4 15297773 GALLERY C AT SHEMYA AFB AK 11/22/1970 11/30/1972 740 2.0 1.0 0.9 0.8 Notes: (a) Gauging at Russell Creek was discontinued on 12/31/1986 and restarted on 10/1/1995. The short data records for the Adak streams, only 3.6 years and 2.6 years for Sweeper Creek and Moffett Creek respectively, present a general concern that an average water year may not be represented. The Russell Creek drainage has data that spans 30 years but is missing 9 years from the period 1987 to 1996. There is about a 7 month overlap between the Russell Creek data and the Adak gauges. However, comparison of the two data sets over this short time does not reveal any meaningful comparison regarding year to year variability. An additional means of identifying adverse water years is through comparing rainfall data with streamflow measurements. The rainfall data for Adak is shown below. Table 4 - Rainfall Data ADAK, ALASKA-500026, Monthly Total Precipitation (inches) File last updated on Oct 22, 2010 *** Note *** Provisional Data *** After Year/Month 199603 a = 1 day missing, b = 2 days missing, c = 3 days, ..etc.., z = 26 or more days missing, A = Accumulations present Long-term means based on columns; thus, the monthly row may not sum (or average) to the long-term annual value. MAXIMUM ALLOWABLE NUMBER OF MISSING DAYS : 5 Individual Months not used for annual or monthly statistics if more than 5 days are missing. Individual Years not used for annual statistics if any month in that year has more than 5 days missing. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 15 YEAR(S) JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ANN 1949 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 6.45 7.30 7.93 12.96 34.64 1950 3.95 2.63 3.39 2.54 3.23 1.35a 2.44 6.42 10.04 5.58 2.54 7.65 51.76 1951 7.57 9.23c 4.65c 6.76g 4.20c 2.15b 3.42 3.22 4.22 10.62 8.65 11.63 69.56 1952 5.00a 5.86b 7.43a 2.48a 5.89a 9.38a 3.43 1.89 4.69 9.82 10.51a 2.54 68.92 1953 9.86 7.22 11.08 7.12 6.47 4.48 0.43a 5.78 5.49 6.41 12.92 4.37 81.63 1954 6.01 6.96 7.97a 2.44 16.10 5.62 4.79 4.59 7.75 6.79 6.12 13.78 88.92 1955 17.34 5.88 4.13 4.75 5.45a 3.20 5.11 2.33 4.80a 12.52a 11.66 13.47 90.64 1956 3.92 6.95 11.99 5.01a 6.82a 4.34 4.38 9.52 10.70 3.38a 5.51 9.46 81.98 1957 12.92 4.40 7.02 9.95 6.05 6.79 1.03b 2.71 5.21 7.10 4.68 8.78 76.64 1958 6.71 2.77 8.31 5.24 5.69 3.74 3.07 1.57 7.47 11.22 11.19 9.61 76.59 1959 3.13 7.15 7.38 3.88 5.25 3.80 2.50 4.44 7.44 7.15 7.23 4.62 63.97 1960 4.35 2.79 2.55 2.31 3.29 1.43 3.04 2.98 2.49 5.31 2.94 3.87 37.35 1961 5.74 2.81 2.33 2.26 2.82 2.97 4.86 2.41 4.74 6.85 7.85 4.90 50.54 1962 5.35 6.44 9.63 1.42 1.68 4.07 2.28 3.95 2.71 8.09 6.14 5.34 57.10 1963 5.30 1.97 8.67 3.79 5.98 3.52 2.17 0.00z 4.50 6.10 6.78 10.16 58.94 1964 4.30 6.10 7.10 6.87 1.12 2.50 2.15 3.68 11.30 5.87 7.12 8.65 66.76 1965 4.80 5.67 5.86 10.17 3.05 3.16 3.88 2.39 5.37 6.66 8.18 6.96 66.15 1966 5.71 8.21 2.57 4.43 5.76 1.36 2.16 6.72 3.76 3.02 11.65 6.72 62.07 1967 7.69 5.05 5.65 4.75 0.64 1.61 6.10 5.28 6.01 7.81 9.59 9.64 69.82 1968 8.89 3.75 3.67 4.99 1.34 1.91 2.37 2.49 3.10 4.95 6.65 8.09 52.20 1969 10.28 5.26 4.28 4.19 3.29 2.04 1.22 4.53 6.77 4.20 7.40 4.17 57.63 1970 6.10 3.76 3.39 6.25 1.55 1.92 2.81 4.75 0.00z 7.83 4.81 0.00z 43.17 1971 3.67 2.07 6.92 3.80 2.54 0.00z 3.41 2.25 6.72 5.47 10.62 0.00z 47.47 1972 6.20 2.93 3.43 2.57 3.01 3.02 2.33 3.78 0.00z 8.71 9.12 0.00z 45.10 1973 2.71 0.00z 6.06 0.00z 2.77 2.95 2.74 5.31 7.83 4.60 8.67 8.01 51.65 1974 5.58 3.78 3.76 5.89 5.37 1.63 4.66 7.34 4.57 3.02 9.89 6.71 62.20 1975 4.03 3.84 5.58 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 7.28 6.48 27.21 1976 3.92o 1.07q 3.89 3.34 2.60 1.55 3.56 3.81 4.56 7.49 3.16o 0.00z 30.80 1977 3.56 3.81 4.85 2.91 3.81 2.68 1.98 4.50 0.00z 6.07 4.98 5.87 45.02 1978 0.00z 4.44 3.99 3.93 3.37 3.17 1.84 2.99 0.00z 6.23 0.00z 8.19 38.15 1979 6.75 4.72 5.53 6.64 0.00z 3.04 2.86 0.00z 4.26 10.01 6.06 6.53 56.40 1980 0.00z 0.00z 6.44 4.36 3.53 3.46 1.68 5.34 4.55 5.66 9.21 5.90 50.13 1981 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00 1982 0.00z 0.00z 0.00z 0.00z 0.00z 3.74 4.92 4.53 6.21 4.08 8.34 4.21 36.03 1983 3.65 4.72 3.03 2.23 1.76 1.70a 2.35 3.60 4.74 7.66 7.34 6.59 49.37 1984 4.97 4.27 0.00z 4.55 2.74 1.67 1.76 0.00z 5.35 4.05 0.00z 6.79 36.15 1985 3.43 2.96a 4.77 3.65 3.71 3.37 1.34 0.00z 4.66 0.00z 0.00z 0.00z 27.89 1986 3.38 3.04 4.17 6.00 3.60 2.22 0.71 0.00z 4.74 0.00z 7.74 0.00z 35.60 1987 0.00z 3.96 0.00z 0.00z 1.92 4.88 0.00z 3.31 0.00z 7.47 0.00z 0.00z 21.54 1988 0.00z 2.80 4.66 2.92 4.43 0.00z 3.57 0.00z 0.00z 6.64 6.22 0.00z 31.24 1989 6.22 2.79 2.96 0.00z 2.76 0.00z 1.28 0.00z 7.34 3.30 0.00z 4.30 30.95 1990 6.60 3.62a 6.11 1.97 4.36 0.90 2.47 6.20 5.01 2.58 3.10 0.00z 42.92 1991 11.39 1.75 6.94 3.79 3.55 3.48 2.76 2.93 7.12 4.64 0.00z 5.74 54.09 1992 0.00z 4.91 5.63 1.61 1.58 5.37 0.00z 3.42 6.35 6.92 6.14 7.54 49.47 1993 9.35 5.35 4.91 3.61 2.30 3.17 3.89 7.62 4.84 9.81 7.02 4.46 66.33 1994 5.66 6.31 3.84 1.43 2.69 2.87 2.48k 4.89f 3.76h 5.40k 3.38f 4.81k 22.80 1995 1.41k 4.10i 1.38d 3.54a 1.73i 0.67d 1.71c 3.45a 7.38f 6.32e 2.69 7.00g 19.76 1996 3.57f 3.51f 4.98g 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00z 0.00 1997 to 2010 No Data MEAN 6.27 4.57 5.43 4.19 3.86 3.09 2.82 4.22 5.78 6.56 7.43 7.28 65.65 S.D. 3.05 1.81 2.34 2.05 2.53 1.66 1.30 1.79 2.01 2.30 2.55 2.80 13.77 SKEW 1.69 0.55 0.81 1.14 2.81 1.52 0.47 0.93 0.99 0.46 0.00 0.71 0.05 MAX 17.34 9.23 11.99 10.17 16.10 9.38 6.10 9.52 11.30 12.52 12.92 13.78 90.64 MIN 2.71 1.75 1.38 1.42 0.64 0.67 0.43 1.57 2.49 2.58 2.54 2.54 37.35 NO YRS 37 40 42 39 41 41 41 36 37 42 38 35 21 The lack of significant overlap between the rainfall data and Russell Creek, Sweeper Creek, and Moffett Creek prevents using the rainfall record for an evaluation of year to year variability in the stream flow records. However, a limited comparison can be made on a monthly basis. There appears to be a low deviation in the observed rainfall and runoff measurements compared with the long term mean rainfall. Based on this limited comparison and due to the general lack of data, it is concluded that the measured runoff at Sweeper TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 16 Creek and Moffett Creek are generally representative of long term average runoff quantities and patterns for the purpose of this analysis. The two Adak sites, despite being only 4 miles apart, exhibit significantly different runoff characteristics. The typical annual runoff profile from Moffett Creek has peaks and valleys inverted from that of Sweeper Creek. During the summer months Moffett Creek has higher unit runoff than during the winter months. Sweeper Creek is the opposite with higher runoff rates in the winter than in the summer. Moffett Creek also exhibits a higher amount of unit runoff overall on an annual basis. A review of the other USGS gauged drainages along the Aleutian Islands and Alaska Peninsula exhibit a similar trend with Russell Creek having a significantly higher unit runoff and all of the remaining sites exhibiting runoff similar to Sweeper Creek. This dichotomy is illustrated in the following chart. Figure 3 - USGS Monthly Average Stream Flow Chart A review of the locations of the drainages indicates that Moffet Creek and Russell Creek have catchment areas located in relatively high elevations with ridges and valleys whereas the other drainages are located in relatively flat and open areas. Notwithstanding other factors in the data sets, it is possible that the higher elevations, ridges, and valleys allow for snow drifting and accumulation that becomes a significant contributor to runoff in those drainages during the summer months. And during the winter months it is likely that the high altitude results in winter precipitation falling as snow and, with lower temperatures, results in reduced runoff. The drainages for Mt. Reed Creek and Lake Bonnie Rose both have catchments with ridges and valleys at higher elevations and therefore the runoff in these basins is expected to be 0.0 2.0 4.0 6.0 8.0 10.0 12.0 123456789101112Average Unit Runoff, cfs/sq miMonth LIMPET C ON AMCHITKA IS AK FALLS C ON AMCHITKA IS AK CLEVENGER C ON AMCHITKA IS AK BRIDGE C ON AMCHITKA IS AK WHITE ALICE C ON AMCHITKA IS AK LK C AT SHEMYA AFB AK GALLERY C AT SHEMYA AFB AK RUSSELL C NR COLD BAY AK MOFFETT C AT ADAK IS AK SWEEPER C AT ADAK IS AK TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 17 similar to the Moffet Creek drainage. The lower drainage areas of Heart Lake and Lake Leone are presumed to have runoff rates similar to the Sweeper Creek. And the mid altitude drainages of Lake De Marie and Lake Betty are expected to exhibit runoff rates that equal the average of the other two. The procedure for determining runoff rates for drainages in this analysis was to calculate the daily average3 unit flow from all years of the record for each of the Adak data sets. This resulted in two data sets, one for Moffett Creek and one for Sweeper Creek, containing an average year of daily unit runoff flows. Then, based on the general altitude for the basin, the unit runoff for each project option was calculated by combining the Moffett Creek and Sweeper Creek data sets appropriately and scaling by the appropriate basin area. The values to derive daily flows for each of the projects options are shown below. Table 5 - Project Stream Flow Derivation Source Daily Unit Flow Basin Area (sq mi) Tributary Flow Lake Bonnie Rose 25%*Sweeper Creek Average + 75%*Moffett Creek Average 1.55 Lake De Marie 50%*Sweeper Creek Average + 50%*Moffett Creek Average 2.04 (3.59 - 1.55) Lake Bonnie Rose Heart Lake 100%*Sweeper Creek Average + 0%*Moffett Creek Average 0.59 (4.18 - 3.59) Lake De Marie Lake Betty 50%*Sweeper Creek Average + 50%*Moffett Creek Average 4.43 Mt Reed 25%*Sweeper Creek Median + 75%*Moffett Creek Median 2.39 Moffett 0%*Sweeper Creek Median + 100%*Moffett Creek Median 2.78 The following table is the resulting monthly average flow for each of the project intake locations. Table 6 - Derived Monthly Average Stream Flows (cfs) for Each Project Location Month Lake Bonnie Rose Lake De Marie Heart Lake Lake Betty Mt Reed Moffet 1 6.7 15.9 18.7 20.0 8.8 10.3 2 7.5 18.3 21.9 23.4 10.3 11.2 3 5.8 13.5 15.8 16.8 7.8 9.3 4 5.7 13.2 15.4 16.4 8.2 10.0 5 6.8 14.1 15.3 15.9 10.4 14.5 6 12.6 24.7 25.6 26.3 19.3 28.7 7 14.0 28.1 29.6 30.5 21.3 31.2 8 9.4 19.8 21.7 22.7 13.8 19.4 9 10.4 22.2 24.6 25.8 15.4 21.0 10 10.8 24.0 27.3 28.8 14.8 18.9 11 9.2 20.8 23.8 25.1 13.4 16.7 12 7.3 16.9 19.6 20.7 10.3 12.4 Average 8.8 19.3 21.6 22.7 12.8 17.0 3 The average unit flow is appropriate if storage is utilized whereas for the run-of-river projects on Moffett Creek and Mt Reed Creek the median flow is used. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 18 9. Project Options and Initial Evaluation Initial analysis found about 13 individual hydroelectric project configurations near Adak. A simple approach to comparing these individual options was adopted to identify the options with the best potential for development. The following discussion presents this approach. Not included in this analysis is the multitude of options possible when the individual projects are combined. Current loads appear to have dropped enough from historic levels such that a single hydroelectric development should meet the majority of demand. The table below summarizes the results of the initial project identification and assessment. Table 7 - Project Options and Analysis Matrix No Source Elev Powerhouse Location Elev Design Flow Penstock Length Dia Net Head Power Electric Length Cost Score Energy Score Environ Score Avg Score ft ft cfs ft in ft kW ft 1 to 5 1 to 5 1 to 5 1 to 5 1 Lake Bonnie Rose 739 Lake DeMarie 249 10.6 5,270 16 445 320 2,500 2.3 3.2 3.5 3.0 2 Lake Bonnie Rose 739 Ocean 25 10.6 9,765 16 632 450 0 1.6 4.9 2.8 3.1 3 Lake Bonnie Rose 739 Ocean 25 10.6 15,032 18 644 460 7,500 0.0 5.0 2.0 2.3 4 Lake Bonnie Rose 739 Heart Lake 168 10.6 13,862 18 506 360 5,000 0.5 3.7 2.5 2.2 5 Lake DeMarie 234 Heart Lake 168 23.1 2,408 24 54 80 5,500 2.8 0.0 3.5 2.1 6 Lake DeMarie 234 Ocean 25 23.1 7,519 26 183 280 7,500 0.5 2.6 2.0 1.7 7 Lake Betty 159 Lake Betty PH 30 27.2 1,335 22 114 210 17,500 2.2 1.7 3.8 2.6 8 Lake Bonnie Rose 739 Exist PRV 315 3.5 0 10.6 364 90 0 5.0 0.9 4.5 3.5 9 Lake Bonnie Rose 739 Exist PRV 315 10.6 8,196 18 385 270 0 1.9 2.5 4.0 2.8 10 Lake Bonnie Rose 739 Mitt Lake 60 10.6 7,263 16 618 440 850 1.9 4.7 3.5 3.4 11 Heart Lake 153 Ocean 25 25.9 3,650 26 112 190 7,500 1.9 1.4 2.0 1.8 12 Mt Reed 400 Ocean 25 15.4 2,543 18 350 360 12,000 2.1 3.7 1.3 2.4 13 Moffet 400 Ocean 25 20.4 10,017 24 334 450 0 0.2 4.9 4.0 3.0 Scores shown in the table are ranked using a low number to representative a negative or detrimental aspect (such as high cost) and a high number to represent a positive aspect (such as high energy output or low environmental impact). Some of the projects utilize the same source and destination elevation but have different pipeline routes and powerhouse locations. It is expected that many of the above options would prove feasibly impractical. Due to the desktop level of analysis and the number and complexity of issues, particularly the uncertainty related to environmental flows and aquatic resources, other water uses, and electrical demand, all of the options that are possible have been retained in this report for reference purposes in future feasibility efforts. The initial analysis presented above does not include storage or useable energy (demand constrained) considerations. The design flow for each configuration, except option 8 using the existing pipeline, is selected as the average annual flow, as calculated previously for each basin, times 120%. The total annual energy production is based on the design flow times a capacity factor. The estimated capacity factor for option 8 is 100% while the other options use a 60% capacity determined from energy analysis using the estimated daily hydrology data. Actual useful capacity factors will be dictated by system load, local hydrology, water system demands, bulk water sales (if any), environmental bypass flows, and storage capability. Transmission lengths were determined by the shortest distance from the powerhouse location to the nearest building group. At this stage in the analysis the results are considered relatively accurate and should only be used for comparison among projects in this study and as a basis for future planning and TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 19 analysis efforts. A project scoring system was developed for assessing and ranking each project based on cost, energy produced, and environmental attributes. The environmental factors assigned are based on estimated impacts to aquatic issues and the physical footprint of the project. Scoring of cost is derived by calculating a cost factor that is based on the pipeline diameter, length, and transmission length. The project with the lowest cost factor has the highest score whereas the highest cost project has the lowest score. Similar to the cost scoring, the ranking of energy is derived by scoring the project with the highest energy output a 5 and the project with the lowest output a 0. Environmental scores are based on a qualitative evaluation of the amount of bypassed reach, the percentage of bypassed flows (excludes consideration of existing water use flows), and the amount of new trail required for the pipeline and transmission lengths combined. The results show that two developments rank the highest:  Option 10, 440 kW Mitt Lake Project - Constructing a storage project utilizing the existing dam at Lake Bonnie Rose for the intake and locating a powerhouse on Mitt Lake.  Option 8, 85 kW Exist PRV Project - Utilizing the existing 10" DIP water system pipeline and installing a turbine near the water treatment plant. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 20 10. Lake Bonnie Rose to Mitt Lake Project Analysis 10.1 Description Option 10 (Mitt Lake Project), the configuration with an intake at Lake Bonnie Rose and a powerhouse at Mitt Lake, with more capacity and higher energy output, appears to be the most feasible option for meeting a majority of energy generation needs economically at this stage of analysis. Option 10 could also be configured as a storage project and is analyzed in more detail in this section. The Mitt Lake Project would utilize a combination of HDPE and steel or ductile iron pipe with a total length nearly the same as that for the existing PRV-1 location. The project is modeled with the following parameters: Peak Flow 10.6 cfs Operating Head 613 ft Head water elevation 739 ft Lake area 139 acre-ft turbine centerline elevation 60 ft Active Storage 3 ft static head 679 ft Storage 418 acre-ft Penstock Length 7,300 ft Eff 0.8 Penstock Diameter 16 in Power 440 kW  Annual Energy Potential 3,209,499 kWh  The hydrograph and flow duration curve for Lake Bonnie Rose with the power potential of Option 10 (excluding other water uses) is shown in the figures below. Figure 4 - Lake Bonnie Rose Hydrograph 0 200 400 600 800 1000 1200 0 5 10 15 20 25 30 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Power Potential (kW)Stream Flow (cfs)Date Lake Bonnie Rose Hydrograph and Power Potential TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 21 Figure 5 - Lake Bonnie Rose Flow Duration Curve 10.2 Analysis The detailed analysis includes consideration of storage and the ability to meet the energy needs of the synthesized hourly demand. The estimated useable storage for the lake is the surface area times a depth of 3 feet. Also included in the analysis are options for supplying the 0.5 cfs of potable water, 0.8 cfs for export, and the monthly environmental flows. Storage in the reservoir is not included when considering environmental flows. The analysis of the performance using the hourly demand data and storage is an approximation that does not include varying efficiency, headloss, minimum diesel run time, or ice and snow effects on storage. For this level of study, the results are generally adequate to test the viability of the concept and assist future feasibility efforts. The charts below shows the results of the Mitt Lake Project operational model with the combined town and processor load and with and without existing environmental water uses. 0 200 400 600 800 1000 1200 0 5 10 15 20 25 30 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%Option 10 Potential Power (kW)Lake Bonnie Rose Inflow (cfs)% Time  Exceeded Lake Bonnie Rose Flow  Duration Chart TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 22 Figure 6 - Mitt Lake Project Operation Chart without Environmental Flow Restrictions Figure 7 - Mitt Lake Project Operation Chart with Environmental Flow Restrictions 735 735 736 736 737 737 738 738 739 739 740 0 100 200 300 400 500 600 700 800 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/1 Reservoir Elevation (ft)Power (kW)Date Mitt  Lake Project Operation Avg Diesel Generation Avg Hydro Generation Resvoir  Level 0 100 200 300 400 500 600 700 800 0 100 200 300 400 500 600 700 800 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/1 Reservoir Elevation (ft)Power (kW)Date Mitt  Lake Project Operation Avg Diesel Generation Avg Hydro Generation Resvoir  Level TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 23 10.3 Cost Estimate The opinion of construction cost (cost estimate) was prepared using cost estimates for other projects and general cost knowledge. This first stage of analysis lacks conceptual designs, a schedule, site visit, surveys, and other investigations that can significantly impact cost. The estimated construction effort spans a period of about 8 months with 5.5 months on location in Adak. The construction support includes housing and per diem at a unit cost $150 per day (the low cost is based on excess housing availability in Adak). Also included are costs for air travel every other week (13 trips) at a rate of $15,000 per trip. Mobilization is based on a presumed rate of $350,000 per trip for a vessel making two round trips from Seattle. The cost estimate for the modifications to the existing dam includes 50 cubic yards of concrete, valves, screens, controls, and a power and communications line from the powerhouse that would follow the pipeline alignment. The pipeline cost estimate includes 4,600 feet of HDPE and 2,650 of steel or ductile iron pipe. Miscellaneous fittings and anchor blocks are included as well. Access trails are included in the cost estimate based on a presumed length of 5,000' and a shot rock material volume of 1 cyd per foot of trail at a cost of $50/cyd. The turbine and generator costs include $500k for the turbine and generator and another $250k for controls, switchgear, and transformer. Equipment budgeted for the project includes a fusion machine, concrete mix truck, two excavators, an end dump, loader, generators, 2 light trucks, and a track drill with compressor all rented for 8 months. Also included is 20,000 gallons of fuel at an estimated retail cost of $7 per gallon (included under materials category of equipment). Due to the preliminary status of the project analysis and cost estimate a 25% contingency is added to the construction cost. A summary of the preliminary opinion of the development cost for the Mitt Lake Project is provided in the table below. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 24 Table 8 - Mitt Lake Project Cost Estimate Item Labor Labor Cost Equip Cost Material Cost Ship Cost Total Cost Construction Support 3,390 $ 322,000 $ 344,000 $ 670,000 Mobilization $ 700,000 $ 700,000 Powerhouse 1,620 $ 132,000 $ 350,000 $ 480,000 Intake 1,800 $ 142,000 $ 82,000 $ 220,000 Pipeline 2,400 $ 190,000 $ 334,000 $ 520,000 Access Trails 1,320 $ 101,000 $ 275,000 $ 380,000 Turbine And Generator 540 $ 51,000 $ 750,000 $ 800,000 Transmission 360 $ 29,000 $ 20,000 $ 50,000 Equipment $ 513,000 $ 140,000 $ 650,000 SUBTOTAL, Direct Costs 11,400 $ 968,000 $ 513,000 $ 1,950,000 $ 1,044,000 $ 4,470,000 Weather delay (% of Labor and Equip) 10% $ 150,000 Contingency 25% $ 1,120,000 Contractor profit 15% $ 670,000 SUBTOTAL, Construction $ 6,410,000 SUBTOTAL, Construction $ 6,410,000 Construction interest $ 140,000 Engineering 12% $ 800,000 Inspection and testing 4% $ 250,000 Owner admin 6% $ 400,000 TOTAL PROJECT $ 8,010,000 10.4 Economic Value The results indicate that storage has some value. The most significant consideration however is the amount of water available for hydropower. The instream flow requirements significantly affect the economics of the Mitt Lake Project and all of the diversion projects using water from the lake system. The tables below show the energy distribution with the hydroelectric project as part of the generation system and the estimated annual fuel savings with the various water use options. Table 9 is for the "town only" demand while Table 10 is for the combined "town and processor" demand. The estimated cost of diesel fuel in Adak is $5.00 per gallon. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 25 Table 9 - Mitt Lake Project Performance Summary (Town load only) Town Load Only Parameter No Competing Water Use Potable Water Use Added Water Export Added Environmental Flows Added Units Annual Energy Demand 2,000,000 2,000,000 2,000,000 2,000,000 kWh Demand Met by Hydro 2,000,000 2,000,000 2,000,000 780,000 kWh Demand Met by Diesel 0 0 0 1,230,000 kWh Current Diesel Use 142,857 142,857 142,857 142,857 gal Diesel Use with Hydro 0 0 0 87,900 gal Annual Fuel Savings (gal) 142,857 142,857 142,857 54,957 gal Annual Fuel Savings ($) $714,286 $714,286 $714,286 $274,786 Net Present Value $14,000,000 $14,000,000 $14,000,000 $5,400,000 Benefit / Cost Ratio (B/C) 1.7 1.7 1.7 0.7 Table 10 - Mitt Lake Project Performance Summary (Town and Processor load) Town and Processor Load Parameter No Competing Water Use Potable Water Use Added Water Export Added Environmental Flows Added Units Annual Energy Demand 3,310,000 3,310,000 3,310,000 3,310,000 kWh Demand Met by Hydro 2,880,000 2,700,000 2,520,000 910,000 kWh Demand Met by Diesel 440,000 630,000 810,000 2,400,000 kWh Current Diesel Use 236,429 236,429 236,429 236,429 gal Diesel Use with Hydro 31,400 45,000 57,900 171,400 gal Annual Fuel Savings (gal) 205,029 191,429 178,529 65,029 gal Annual Fuel Savings ($) $1,025,143 $957,143 $892,643 $325,143 Net Present Value $20,100,000 $18,800,000 $17,500,000 $6,400,000 Benefit / Cost Ratio (B/C) 2.5 2.3 2.2 0.8 From the tables it can be seen that, with the processor load added, the water export operation has some impact on the economics. However, with proper timing, use of additional sources and storage, the overall impact could be negligible. The environmental flow requirements are significant enough that it appears the export operation may be curtailed at times. The environmental flow restrictions reduce the value of the hydro by about $600,000 annually with the processor load considered. This equates to a net a present cost of preserving resident fish at about $11.7 million over 30 years. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 26 11. Existing PRV Project The Existing PRV project utilizes the existing raw water transmission pipeline from Lake Bonnie Rose to the water treatment plant. The pipeline is reported to be a 10" DIP. A standard wall thickness is assumed resulting in an internal diameter of 10.6". A hydraulic capacity of 3.5 cfs is selected for this option which results in a relatively high frictional loss but the turbine is not expected to operate over a wide range flows. The water available for power is reduced to 3 cfs when including the potable water needs of 0.5 cfs. This project is limited in the amount of power output due to the existing pipeline. It is sized to the practical maximum which varies from about 75 kW to 90 depending on the domestic water needs. This consideration must be taken into account when comparing with the Mitt Lake project size which is fairly flexible. It can be expected that the Mitt Lake project size, and economics, will be optimized with further feasibility analysis. The output of this project is lower than the towns demand and would require continuous diesel operation throughout the year. Since the operational model for this report did not include diesel engine maintenance, overhauls, and replacement costs the economical comparison to the Mitt Lake project is not entirely accurate. The Mitt Lake project will result in additional cost savings that is not accounted for in this analysis. A preliminary estimate of construction cost was prepared for the Existing PRV project using the cost estimate from the Mitt Lake project and is shown in the table below. The pipeline cost is zero in the estimate but a more appropriate comparison with the Mitt Lake project would consider the age of the existing pipeline and the remaining service life and replacement cost. Table 11 - Existing PRV Cost Estimate Item Labor Labor Cost Equip Materials t Shipping Total Cost Construction Support 450 $ 43,000 $ 135,000 $ 180,000 Mobilization $ 300,000 $ 300,000 Powerhouse 1,080 $ 88,000 $ 250,000 $ 340,000 Intake 600 $ 47,000 $ 59,000 $ 110,000 Pipeline Access Trails 660 $ 51,000 $ 100,000 $ 150,000 Turbine And Generator 540 $ 51,000 $ 345,000 $ 430,000 Transmission Equipment $ 66,000 $ 18,000 $ 80,000 SUBTOTAL, Direct Costs 3,300 $ 280,000 $ 66,000 $ 804,000 $ 435,000 $ 1,590,000 Weather delay (% of Labor and Equip) 10% $ 30,000 Contingency 25% $ 400,000 Contractor profit 15% $ 240,000 SUBTOTAL, Construction $ 2,250,000 SUBTOTAL, Construction $ 2,250,000 Construction interest $ 50,000 Engineering 13% $ 300,000 Inspection and testing 2% $ 50,000 Owner admin 4% $ 100,000 TOTAL PROJECT $ 2,750,000 The potential energy and economic benefit of the Existing PRV project has also been analyzed using the same model developed for the Mitt Lake project. As with the Mitt Lake TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 27 project, reservoir storage is assumed to be zero when including environmental flows. The results are shown in the table below for the town load only. Table 12 - Existing PRV Project Performance Summary (Town load only) Town Load Only Parameter No Competing Water Use Potable Water Use Added Water Export Added Environmental Flows Added Units Annual Energy Demand 2,000,000 2,000,000 2,000,000 2,000,000 kWh Demand Met by Hydro 760,000 650,000 650,000 330,000 kWh Demand Met by Diesel 1,240,000 1,350,000 1,350,000 1,660,000 kWh Current Diesel Use 142,857 142,857 142,857 142,857 gal Diesel Use with Hydro 88,600 96,400 96,400 118,600 gal Annual Fuel Savings (gal) 54,257 46,457 46,457 24,257 gal Annual Fuel Savings ($) $271,286 $232,286 $232,286 $121,286 Net Present Value $5,300,000 $4,600,000 $4,600,000 $2,400,000 Benefit / Cost Ratio (B/C) 2.1 1.9 1.9 1.0 The resulting benefit to cost ratios are somewhat similar to the Mitt Lake project. However, the overall value of the Exist PRV project is much lower with a Net Present Value (NPV) of $4.6 million compared with the NPV of $14 to $18.8 million for the Mitt Lake project. Even when including environmental flows, the NPV of the larger Mitt Lake is more than double that of the Existing PRV project. It is premature to recommend a proposed develop until further feasibility efforts are undertaken to optimize project sizing and efforts are made to reduce the environmental flows. However, considering that the life of a hydropower project is much longer than the economic term adopted in this report the most favourable development would be an appropriately sized Mitt Lake project even when considering environmental flow restrictions which are subject to change. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 28 12. Recommendations The preliminary analysis indicates that a hydroelectric project in Adak is economically viable without the environmental flow restrictions. The environmental flow restrictions significantly impact the hydro potential but it is worth pursuing development efforts and to try to reduce or eliminate the restrictions given the low value of the resident fresh water species and the high value of the use of water for power production. Additional consideration of many issues and more thorough feasibility analysis is necessary to determine the best development scenario. Additional feasibility study is warranted to collect site specific data, initiate permitting actions, and refine the analysis to determine recommended project(s), storage potential, conceptual designs, and costs. Recommendations include:  Obtain current satellite image and perform a satellite photogrammetric or LIDAR survey over the entire project area (from Moffet drainage south to the Aleutian Wilderness boundary).  Monitor and log 15 minute demand data to determine daily load fluctuations. Also log hourly or daily demand with peaks over a longer period.  Coordinate conceptual designs and development efforts with the water system and bulk sales.  Install and maintain stream gauges in Adak for a minimum of one to three years. At a minimum one should be placed at the outlet of Lake Bonnie Rose.  Initiate the additional permitting and mitigation for the removal of instream flow restrictions and allow for the diversion of water.  Perform feasibility level studies to further evaluate issues related to aquatic habitat, incorporate stream gauge work into the hydrology analysis, and develop more detailed project cost estimates, size, and storage recommendations, and conceptual designs.  Investigate future load growth (or decline), fish processor loads, and further evaluate demand requirements. TDX Power - Adak Reconnaissance Study Final Report Prepared by Hatch, 2/16/2013 H343115-0000-00-236-0001, Rev. 1 Page 29 13. References Alaska Department of Commerce, Community, and Economic Development, Division of Community & Regional Affairs. Alaska Community Database Community Information Summaries (CIS). http://www.commerce.state.ak.us/dca/commdb/CF_CIS.htm. Alaska Journal of Commerce. Wesley Loy. Aleut Corp wants to export Adak Water. http://www.alaskajournal.com/stories/082010/loc_adw.shtml. Bristol Environmental & Engineering Services Corporation. Adak Water and Sewer Improvements. Prepared for City of Adak. July, 2010. HDR Inc. Adak Island Lakes Draft Fisheries Field Report, August 2011. Peratrovich, Nottingham & Drage, Inc. Adak Lake Surveys. December 2010. URS Corp and US Navy, 2009. Environmental cleanup and closure of the former Naval Air Facility, Adak, Alaska. Website: http://www.adakupdate.com/ Waythomas, Christopher F., 1995. Surficial Geologic Map of Northern Adak Island, Alaska. U.S. Geological Survey Open-File Report 95-1 28. http://www.dggs.dnr.state.ak.us/pubs/quad/adak. WHPacific. Safety Inspection Report, Lake Bonnie Rose Dam, Adak, Alaska, NID ID No. AK 00108. Prepared for City of Adak. April 03, 2012. WHPacific. Safety Inspection Report, Lake De Marie Dam, Adak, Alaska, NID ID No. AK 00123. Prepared for City of Adak. April 03, 2012. 1225 East International Airport Rd., Suite 110 Anchorage, AK, USA 99518 Tel (907) 561 2800  Fax (907) 561 2802 McMillen Sept. 2013 report 2022 Adak Petroleum invoice Canyon Hydro Quote November 28, 2022 Loren A. Jalbert TDX Power Services, LLC 208-375-5323 ljalbert@tdxpowerservices.com Dear Mr. Jalbert, Thank you for contacting Canyon Hydro regarding the site evaluation requirements at Adak. As always, we welcome the opportunity to offer our expert assistance as listed below. • (1) Travel to the Adak site (Tuesday/Wednesday) • (1) Review site and note potential hydro options (Thursday/Friday) • (1) Travel from the Adak site (Saturday/Sunday) • (1) Airfare to and from Adak • (2) Hotel nights in Anchorage • (1) Lot meals and ground travel • We understand lodging and transportation will be provided in Adak Estimated price for the field services listed above……………………………………..................$15,650.00 Our normal terms are 50% payment prior to departure and 50% due upon return from the visit. We will waive this requirement if the City of Adak provides a purchase order to Canyon. If a PO is not an option, we will send an invoice for $7,825.00. Balance to be determined by actual time spent and travel costs. Our proposed engineer is Mike Maloney. Please find attached Mike’s resume. He is our electrical engineer and has a great deal of experience with evaluating hydroelectric sites. Mike’s experience will be used to prepare a report based on the findings noted during his visit. I welcome questions you may have regarding our proposed services. Sincerely, Eric Melander Vice President of Sales General Provisions for Field Service Effective January 1, 2022 Field Service Rates Technician $1,400 per day (based on 8 hour work day) Overtime/weekends $200 per hour Engineer or Executive $2,000 per day (based on 8 hour work day) Overtime/weekends $285 per hour Transportation Personal or Corporate automobile mileage charged at $0.625/mile. Air, rail, rental car, etc. will be charged at cost plus 15% processing charge. Lodging & Meals Charged at cost plus 15% processing charge. Travel Travel time will be billed at the straight time hourly rate Mondays through Fridays and at the weekend rate for Saturdays, Sundays, and Holidays. General Provisions Standby Time Any waiting time when the Representative is available to work, up to a maximum of eight (8) hours on any one working day, shall be regarded as time actually worked, even though the services are not actually utilized. The rate may not be prorated for partial days. Delays Canyon Industries, Inc. shall not be liable for delay in performance when such delay is occasioned by causes beyond its reasonable control, including but not limited to acts of God, acts of the customer, material shortages, transportation difficulties, flood, strikes, epidemics, war (declared or undeclared), riot, etc. Emergency Work The minimum time off for a representative during any 24 hour period must be eight (8) consecutive hours. Terms of Payment A deposit equal to 50% of anticipated charges due upon request for a field representative. Payment for services and material will be due upon presentation of invoices. Rates subject to change without notice. B/C Ratio file - 440 kW Hydroelectric Turbine *see attached Excel file B/C Ratio file - 100 kW Hydroelectric Turbine *see attached Excel file