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Old Harbor Hydroelectric Reconnaissance and Feasibility Report - Jul 2011 - REF Grant 2195431
ISO 9001 Alaska Village Electric Cooperative Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report FERC Project Number P-13272 Alaska Energy Authority REF Grant 2195431 Project Permitee: ALASKA VILLAGE ELECTRIC COOPERATIVE Anchorage, Alaska July, 2011 Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page ii © Hatch 2011/07 Table of Contents Terms, Acronyms, and Abbreviations ........................................................................................................... iv 1. Introduction ............................................................................................................................................ 1 2. Feasibility Issues ...................................................................................................................................... 1 2.1 Project Size .................................................................................................................................... 2 2.2 Turbine Configuration .................................................................................................................... 3 3. Cost Information ..................................................................................................................................... 4 3.1 Overview ....................................................................................................................................... 4 3.2 Schedule ........................................................................................................................................ 5 3.3 Equipment and shipping................................................................................................................. 5 3.4 Powerhouse ................................................................................................................................... 6 3.5 Turbine Cost .................................................................................................................................. 6 3.6 Intake ............................................................................................................................................. 6 3.7 Pipeline ......................................................................................................................................... 7 3.8 Transmission and Roads ................................................................................................................. 7 3.9 Indirect Costs ................................................................................................................................. 8 4. Power Study ............................................................................................................................................ 9 4.1 Methodology ................................................................................................................................. 9 4.2 Old Harbor Demand ...................................................................................................................... 9 4.3 Hydrology .................................................................................................................................... 11 4.4 Power Production ........................................................................................................................ 13 4.5 Project Selection .......................................................................................................................... 14 5. Results ................................................................................................................................................... 16 5.1 Cost Comparison .......................................................................................................................... 16 5.2 Cost Detail ................................................................................................................................... 16 5.3 Project Benefits ............................................................................................................................ 17 6. Economic Analysis ................................................................................................................................. 19 6.1 Diesel Integration ......................................................................................................................... 19 6.2 Economic inputs .......................................................................................................................... 19 6.3 Economic Results ......................................................................................................................... 20 6.4 Sensitivity Analysis ....................................................................................................................... 21 7. Conclusions and Recommendations ...................................................................................................... 22 7.1 Conclusions ................................................................................................................................. 22 7.2 Recommendations ....................................................................................................................... 22 8. References ............................................................................................................................................. 23 Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page iii © Hatch 2011/07 Appendix A Opinion of Probable Cost 525 kW Project with 50% Installed Capacity .......................... A-1 Appendix B Construction Schedules ........................................................................................................ B-1 Appendix C Project Drawings .................................................................................................................. C-1 Appendix D Project Description ............................................................................................................. D-1 Appendix E Mountain Creek Hydrology Report, Old Harbor, Alaska ...................................................... E-1 Table 1 – Turbine and Generator Price Schedule ............................................................................................ 6 Table 2 – Indirect Costs .................................................................................................................................. 8 Table 3 – Old Harbor Demand Summary ..................................................................................................... 10 Table 4 – Adjustment Factors for Measured Stream Flows at Intake .............................................................. 12 Table 5 – Pipe Selection Along Project Alignment ........................................................................................ 13 Table 6 – Pipe Diameters, Flows, Losses, and Power Output ........................................................................ 14 Table 7 – Project Alternatives Comparison ................................................................................................... 16 Table 8 – Opinion of Probable Cost Summary – 525 kW Project with 50% Installed Capacity ..................... 16 Table 9 – Annual Fuel Savings with Hydro Project ....................................................................................... 17 Table 10 – Economic Parameters .................................................................................................................. 20 Table 11 – Economic Summary .................................................................................................................... 21 Table 12 – Benefit to Cost Ratio Sensitivity Analysis ..................................................................................... 21 Table 13 - Monthly Average Mountain Creek In-stream Flow and Diversion Potential (cfs) ......................... D-2 Figure 1 – Project Capacity and Installed Capacity ......................................................................................... 4 Figure 2 – Photo of Water Tank Access Road and Quarry at Beginning of Project (Old Harbor Native Corp) .. 8 Figure 3 – Old Harbor Average Daily Demand Fluctuations ......................................................................... 10 Figure 4 – Old Harbor Project Hydrograph and Approximate Power Potential ............................................. 12 Figure 5 – Flow Duration Curve for the East Fork of Mountain Creek ........................................................... 12 Figure 6 – Old Harbor Hydro Annual Energy Potential ................................................................................. 14 Figure 7 – Project Optimization Chart .......................................................................................................... 15 Figure 8 – Hydro Output (Adjusted Hydrology Data) and Diesel Generation Requirements ......................... 18 Figure 9 – Hydro Output (Unadjusted Hydrology Data) and Diesel Generation Requirements ..................... 18 Figure 10 – Chart of Mountain Creek In-stream Flow and Diversion Potential (cfs) ..................................... D-3 Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page iv © Hatch 2011/07 Terms, Acronyms, and Abbreviations TERM MEANING AEA Alaska Energy Authority AVEC Alaska Village Electric Cooperative BTU British Thermal Unit cfs Cubic feet per second cyd Cubic yards ea Each FERC Federal Energy Regulatory Commission gal Gallon HDPE High density polyethylene ID Inside diameter kVA Kilo Volt-Amps kW Kilo Watt (1000 Watts) kWh Kilo Watt-hours lb Pound mi Mile mmBTU 1 million BTU's mo Month O&M Operation and Maintenance OD Outside Diameter OPC Opinion of Probable Cost SDR Sidewall Diameter Ratio sq ft Square feet sq mi Square mile sq yd Square yard . Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 1 © Hatch 2011/07 1. Introduction This feasibility study and cost estimate has been prepared for Alaska Village Electric Cooperative (AVEC) to facilitate project financing, permitting, and final design. The scope of this report is primarily limited to a technical analysis of costs, selection of project size, and estimate of displaced diesel generated electrical energy. More general information on the Old Harbor project can be found in the Federal Energy Regulatory Commission (FERC) e-library under the current license number P-13272. The study is based on preliminary concept drawings and assumed construction methods. The study describes various project alternatives, analyzes the amount of power produced by each alternative, estimates the cost of each alternative, and provides a recommended project configuration. The report is organized with an overview of the primary issues related to feasibility, discussion of cost estimating and pricing details for major components followed by the power study methodology and the analysis of demand, hydrology, hydroelectric power modeling, and a rationale for selection of a project size. Finally, a comparison of the alternatives is provided with a discussion of the results of the study and details of the project benefits and results of the economic analysis. 2. Feasibility Issues Of the many issues that determine the feasibility and selection of project size to construct, this report focuses on the cost, energy, and economic issues. The broader range of issues relating to the development are briefly addressed below. Geotechnical: Soils in Old Harbor consist of a uniform layer of organics and peat approximately 2 feet deep overlying rock formations. Environmental: The Old Harbor project diverts water from the East Fork of Mountain Creek to the Lagoon Creek basin for power production. Extensive environmental investigations were performed as part of the previous FERC licensing effort, P-11690. A final environmental assessment was issued as part of the FERC issued original license for a 500 kW project utilizing 13.2 cfs. A summary of this work is included in the Preliminary Application Document and the results of additional investigations will be submitted under the current licensing effort. Documentation sources are found in the reference section. Site Control: Acquisition of property rights will be required from the US Fish and Wildlife Service, the State of Alaska, Old Harbor Native Corporation, and the City of Old Harbor. Acquisition is dependent on AVEC receiving a license to construct from FERC, a Right of Way permit from the USFWS, and a conservation easement waiver from the Exxon Valdez Trustee Council. The previously licensed project received, or was close to receiving, these and other property permissions therefore it is expected that the same will come about through the licensing process for this project. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 2 © Hatch 2011/07 Permitting: Permitting follows the FERC licensing effort as well. The final environmental assessment will form the basis for the FERC license, USFWS Right of Way permit, USACE permits, and permits from the State of Alaska and Kodiak Island Borough. Cultural: Cultural resources investigations have been performed as part of the FERC licensing process and reports of investigations and recommendations can be obtained through the FERC elibrary system. Operation and Maintenance: AVEC will be responsible for operation and maintenance of the project. Details on O&M will materialize at the end of the FERC licensing process and design effort where any required monitoring and mitigation will be determined. An analysis of O&M related to the existing diesel plant and the proposed hydro is included in this report. The long term operation and maintenance of the hydroelectric project will be less than that of diesel operation. Financing and Economics: A brief analysis of the economics is included in this report but final financing terms and economic evaluation will be a work in progress that will also depend on the outcome of the licensing and efforts. Conceptual Design: Conceptual plan maps are included in Appendix C along with conceptual drawings for the intake and the access trail. While the conceptual design drawings are preliminary, this report is based on a detailed analysis of pipeline and turbine performance. The high level of detail in the analysis is expected to approximate actual project operation closely. 2.1 Project Size The initial analysis found that even the smallest project configuration considered would displace about 90% of Old Harbor's current diesel generation. After the cost estimate was completed, it was also apparent that construction involved a large amount of fixed costs that were independent of project size. Consequently, increasing the capacity of the project well above current demand requirements could be done with only small incremental increases in total cost. Due to the high overall cost of the project and the relatively small demand requirements, configuring the project to be as economical as possible is also a critical factor. Determining the size of project to construct became a central issue of the analysis. Future demand growth is a key factor in determining overall economics and project size. The estimation of demand growth is quite difficult because it is highly dependent on future funding scenarios, population, industrial and commercial development, and the cost of fuel over a very long time period. In lieu of considering potential demand growth, this report focuses on selecting a project size determined by maximizing energy output with the least capacity and cost. Implicit with this assumption is that future load growth, although undefined at this point, will occur if this project is constructed. This approach results in a project size that is generally consistent with past project development efforts1. 1 Locher Interests / Harza Northwest / ISER report of 1998 recommended a 500 kW project using an average pipe ID of 16". Voxland (Locher Interests report) recommended a 600 kW project. A 330 kW project using a 16" OD pipeline was recommended by Polarconsult (1995 Feasibility Study). Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 3 © Hatch 2011/07 The purpose of analyzing various project sizes, all of which meet current demand requirements, is to determine an optimal project size that would accommodate future load increases without constructing too much stranded capacity. This approach is adopted based on the assumption that the pipeline is not expandable. Due to the very long length of the pipeline, the remote location, and the complex topography it would be cost prohibitive to either replace the pipeline with a larger size or add a second pipeline alongside the original at some point in the future for marginal gains in capacity. 2.2 Turbine Configuration Initial analysis focused on whether installation of the full project capacity in a single or dual turbine configuration was preferable. Subsequent findings indicated that the cost of the project was quite high and that all reasonable efforts should be made to remain economical. Given that the present day peak demand in Old Harbor is substantially less than the proposed project capacity, the analysis includes construction of partial capacity by planning for two turbines but installing only one of the units. Selection of the generation capacity was chosen on the basis of meeting current peak demand (160 kW) plus 25% while maintaining identical generation units in any multiple turbine configuration. While the peak capacity of the pipeline is fixed, an additional turbine and generator can be added easily if planned for. This approach allows for lower initial construction costs without sacrificing future capacity potential. Future costs and revenue associated with supplying the additional turbine to meet future load growth is not included in the economic analysis. Although only one turbine is included in the cost estimate, tables and charts depicting the amount of energy produced are based on the full project capacity with both turbines installed. This approach, explained in the previous section, is based on comparing project potential as opposed to project utilization. Estimated project utilization, based on current demand, is the same regardless of project size. Tables and charts showing the cost of the project are based on one of two turbines installed when dual turbines are recommended. The project capacity and generation capacity used in this report are depicted graphically in the following chart. Details regarding the turbine configurations are included in the Cost Information section. Multiple Turbine Configurations A dual turbine installation allows for continuous operation while performing inspection or maintenance on the other unit. Typical downtime for inspection is about one day a year and expected failures may result in a week offline A dual turbine configuration as a base load project needs to synchronize 2 units. If a diesel is added to supplement the turbines then there are 3 generators to control and synchronize adding to the complexity of the system. A single 680 kW turbine could operate with reasonable efficiency down to the minimum flows. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 4 © Hatch 2011/07 Figure 1 Project Capacity and Installed Capacity 3. Cost Information 3.1 Overview The physical layout of the project is based on the March 2010 project drawings found in the FERC e- library for the Old Harbor Hydroelectric Project (P-13272). Copies of the drawings are included in Appendix C. The overall approach taken in the development of this estimate is from a contractors construction perspective where quantities and pricing have been examined in detail. Also, the estimate has been prepared to reflect a traditional construction project and there is no attempt to reduce the total cost through value engineering methods or possible lower cost alternatives. This results in an estimate that should equate to the average to high range of responsive construction bids. Overall logistics for the construction involve shipping all materials from Seattle directly to Kodiak. From there, materials would be unloaded from containers and shipped by landing craft barge to Old Harbor. Equipment will be shipped to and from Kodiak and remain on site for a 6 month period. As discussed above, no attempt has been made to reduce costs by optimizing equipment utilization and shipping schedules. The opinion of probable cost (OPC) is based on the single season construction schedule in Appendix B. A number of different project sizes were evaluated as part of this cost estimate to facilitate the selection of pipeline size and turbine capacity for inclusion in the FERC License application. The comparison includes determination of potential annual energy generation, displaced diesel generation, and construction costs associated with each project size. The cost estimate accounts for changes in the project size by adjusting the following variables: Pipeline material cost by weight. Pipeline shipping cost to Kodiak by number of containers. Pipeline staging cost along the alignment by helicopter placement. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 5 © Hatch 2011/07 Turbine and generator cost. Variables not subject to change in the OPC include pipeline installation and assembly cost. The reason being that trenching would probably be done in a single pass using a bucket sized for the pipeline resulting in negligible changes in excavation time. Also, fusing times for the HDPE are primarily based on setup times and thicknesses which do not vary much for the small sizes being considered. The steel pipe is assumed to be assembled by mechanical couplings that will require very nearly the same time to assemble for all the pipe sizes considered. Differences in the intake size, valves, powerhouse, transmission, and tailrace sizes are all considered too minor to evaluate for the low flow rates and power differences being considered and as a percentage of total project costs. 3.2 Schedule A schedule for the construction was developed to assist with the cost estimating. The construction window for work in the upper reaches of the project extends from about June through October. Equipment and labor were adjusted to ensure that production rates met this limitation. The intake and pipeline construction and the required intake access trail are the primary drivers for the schedule. The actual start of the project is set for the beginning of May. The date for material mobilization is based on a 4 month procurement window after license issuance for pipe and other materials (including the powerhouse) from Seattle. The schedule is included in Appendix B. Although not used in the OPC, a two season construction schedule is also included in Appendix B. 3.3 Equipment and shipping Mobilization is based on shipping all materials from Seattle to Kodiak. Samson quoted $5000/container although $6000 is used in the estimate. Equipment is expected to originate in Kodiak. Subsequent shipping of materials and equipment to Old Harbor is accomplished by landing craft. The landing craft is capable of handling loads of up to 80k pounds or up to an equivalent of 4 containers when stacked (containers must be unloaded). This estimate assumes that, on average, 2 containers can be shipped at once for material and that 5 trips each at the beginning and end of the project are required to haul equipment. Each trip with the landing craft to Old Harbor is $6000 (M/V Lazy Bay) although the cost estimate uses $7500 to account for additional costs associated with unloading and dock fees. A helicopter quote was obtained from Maritime helicopters in Homer. Haul time is based on 40' pipe sections and load carrying capacity. In lieu of using a helicopter, track haulers (Marookas) could be used to haul pipe resulting in some potential savings. The adequacy of the access trail will dictate whether this is a viable option. The helicopter option has the potential to reduce the amount of shot rock used on the construction trail although this potential savings is not included in the estimate. Equipment rental rates listed in the estimate are based on published rental rates from Craig Taylor equipment and a quote from Brechan for the Marookas. Housing costs are estimated based on the rental of 4 houses for 6 months. Contractor air travel is based on 2 charters per month from Kodiak. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 6 © Hatch 2011/07 3.4 Powerhouse Concrete material costs of $200/cyd are based on pricing of similar projects. The Old Harbor cost estimate includes 6 weeks of labor to construct the powerhouse. The building cost of $130/sq ft is based on past experience with building construction. This is likely higher than most industrial metal buildings but the building is also relatively small. A price quote for the crane was not obtained. The tailrace construction is based on creating a stream channel from the powerhouse to the pond and from the pond to the existing upper limit of the Lagoon Creek Tributary. Material costs are estimated based on a preliminary design ($21/ft). A culvert is included at the powerhouse to allow for vehicle travel over the tailrace. An earthen dike is also included to confine tailrace flows to the Lagoon Creek Tributary. In lieu of a constructed stream channel a 30" culvert ($30/ft) could be used to discharge tailrace waters into Lagoon Creek. 3.5 Turbine Cost Turbine and generator costs are based on a budgetary quote from Canyon Industries for a 500 kW unit with controls for standalone operation. Other size turbines are based on separate price quotes and interpolation. Where dual turbines are considered, the cost includes only one of the turbines but adds an estimated bifurcation and equipment cost. The following table shows the price of the turbine and generator used in the cost estimate for various size projects. An additional $150k is included elsewhere for additional controls and integration with the existing diesel power plant. Switchgear price, not included in the turbine pricing, is fixed (independent of project output) and is estimated at $50k. Table 1 Turbine and Generator Price Schedule Pipe Size Project Capacity Turbine Arrangement Installed Capacity Turbine Package Piping/Acc Total Turbine Package Cost 12 172 Single 172 $350,000 $0 $350,000 14 266 Single 266 $460,000 $0 $460,000 16 381 Single 381 $570,000 $0 $570,000 18 525 Dual 262 $450,000 $40,000 $490,000 20 669 Dual 335 $530,000 $60,000 $590,000 22 821 Dual 410 $590,000 $83,000 $673,000 24 994 Dual 497 $670,000 $113,000 $783,000 3.6 Intake The cost of the intake works is based on hauling premixed bags of aggregate and cement in using Marooka's and mixing on site using water from the creek and a 1/3 yard mobile mixer for construction of the concrete diversion structure. Additional work includes construction of a screening/desander box with a trachrack, screens, and gates for filtering of the water. Concrete material pricing at the intake is doubled to account for the remote location. Other prices on the intake works are estimated based on past experience. A preliminary intake concept design with quantity estimates in included in Appendix C. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 7 © Hatch 2011/07 Communication to the intake is required to transmit head level information to the turbine controller. Additional data channels, including IP data connectivity, are desirable for monitoring purposes. The cost estimate includes pricing of a direct bury 4 pair communications cable. The estimate also includes price information based on budgetary quote for a direct bury aluminum conductor and two 15 kVA single phase transformers to provide power to the intake. 3.7 Pipeline Pipeline material costs were quoted on a budgetary per pound basis. This facilitated cost estimation of different project sizes. HDPE cost was quoted $1.00/pound by ISCO pipe with a projected increase in the near future of about 10%. The cost estimate uses $1.20/pound. The estimated rental rate of the fusion machine in the OPC is very close to the quoted purchase cost of a new 20" tracstar machine. The option of supplying HDPE in Seattle with flanged ends and ductile iron backing rings fused onto the pipe by the factory was considered. An analysis of the labor and equipment savings associated with elimination of the fusion machine indicates a small potential savings for the smallest pipe sizes (12 and 14) only. Steel pipe was quoted by Northwest at $1.25/pound coated. The estimate uses $1.50/pound based on expected near term price increases. Steel pipe coupling prices are based on using Victaulic painted style 77 couplers. The coupler prices for each pipe size adjust accordingly. Although not suitable for all of the joints in the steel pipe, the cost per coupling should approximate welded alternatives. Other pipeline material costs are estimated including thrust and restraint anchors. The cost estimate assumes installing rock anchors at each bend. A total of 50 anchors, 3 minor thrust blocks, and a major thrust block near the powerhouse are estimated. Labor cost for the construction of the pipeline, after completion of the trail, is based on a production rate of 20' per hour. 3.8 Transmission and Roads The access trail to the intake represents a significant portion of the construction cost for the project. The quality of the trail affects the productivity of hauling materials and laborers to the work site and impacts pipeline installation. Without a stabilized trail, erosion becomes a problem during construction and future maintenance is negatively impacted. Construction methods can be employed that can reduce the effort put into the trail. With placement of materials by helicopter and mechanical pipe joints the level of effort put into the trail may be lessened. Such decisions are more appropriately addressed during the design and construction phase and, to remain somewhat conservative, the construction of a fully stabilized trail is incorporated into the cost estimate. A preliminary concept drawing for the trail is included in Appendix C. Costs for the pipeline access trail include a quoted, all inclusive cost for shot rock from Brechan Enterprises in Kodiak, developed and staged at the pit near the water tank (beginning of project) of $15 per cubic yard (Brechan developed the pit and constructed the water tank access road in 2010). Volume of shot rock is based on a 12' wide trail with 2' of fill. Other estimated costs for the access trail include geo-textile filter fabric and soil stabilization over the entire length, culverts, and an access gate. Labor is based on a production rate for three Marooka track haulers capable of hauling a 5 yard load at a speed of 2.5 mph up and 5 mph down. Rock excavation in the upper portions of the access trail, particularly in the section near the intake, represents a potential material savings that is Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 8 © Hatch 2011/07 not included in the estimate. An additional 2 weeks is budgeted for culvert installation and erosion control. Figure 2 Photo of Water Tank Access Road and Quarry at Beginning of Project (Old Harbor Native Corp) As with the pipeline trail, the powerhouse access road is based on a fill over fabric on existing grade. Width is 24' and depth of 1.5' of shot rock and 6" of crushed rock. The cost estimate uses the Brechan quote of $25 per cubic yard for using a crusher brought to the site. Labor production rate for the road is estimated at about 40' per hour. Overhead transmission line costs are estimated and equate to about $140,000 per mile. 3.9 Indirect Costs Overhead costs include a mix of percentages applied to the direct construction costs and flat fees. It is assumed that the owner will procure the turbine, generator, and controls work directly. Indirect construction costs include the following: Table 2 Indirect Costs Indirect construction costs Rate Note Weather delay 5% Applied to Labor and Equipment Cost contingency 15% High level of detail in estimate warrants a lower contingency contractor profit 15% Standard profit margin for construction contract bonding 2% Performance bond and other Insurance Indirect project costs Rate Note construction interest 2.25% Finance half the cost of construction at a 9% rate for 6 months engineering Flat fee Fees for design and procurement documents inspection and testing Flat fee Fees for asbuilts, O&M manuals, and startup costs owner admin Flat fee Owner supervision, inspection, and training Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 9 © Hatch 2011/07 4. Power Study 4.1 Methodology The model created to evaluate the costs and selection of the hydroelectric project requires an evaluation of the hydrology and calculating performance for each configuration of the hydroelectric project. Modeling is based on daily values although daily fluctuations in demand are included as well in the benefit analysis. The following sections describe the details of the model development and results. 4.2 Old Harbor Demand Demand growth is expected to remain flat (based on historical trends). AVEC provided 2010 load information consisting of monthly summaries and 15 minute average kW readings. The monthly summary data shows that total energy production with diesel in 2010 was approximately 810,000 kWh with a peak load of 160 kW. The primary generator in Old Harbor is a 1,200 rpm electronic fuel injected Detroit diesel. Installed in 2005, this unit is designed to operate efficiently over a wide range and at low load. Older mechanically injected Caterpillar units provide backup. AVEC also provided 15 minute average data for 12/26/2009 through 12/29/2010. Data was missing from 3/6/2010-3/27/2010 and 12/1/2010-12/8/2010. The missing data was filled in by copying data from other dates with similar loads. With a complete data set a daily average load profile was calculated to determine the magnitude and duration of peak demand in comparison to average daily demand. Differences in the monthly summaries and 15 minute data were minor except monthly peak loads in the 15 minute data set are about 93% of those reported in the monthly summary. This is likely due to instantaneous peaks occurring within the 15 minute intervals. Modeling of displaced diesel to determine the potential benefit gained from the hydro project involved determining how much diesel usage would occur during hydro operation. The model assumes a diesel must come online before the demand actually meets the hydro output and the diesel will run at a specified minimum load for a minimum amount of time. Using the 15 minute data set, if the daily peak demand exceeded 90% of the hydro output then the model assumes that a diesel generator will be started and run at no less than 10% load for at least the number of peak hours in the day, which is about 16 based on the daily load fluctuation. AVEC reports that the diesel generators installed in Old Harbor are 235 kW. The following table compares the monthly and 15 minute demand data provided by AVEC while the following figure shows the daily load profile in Old Harbor using the 15 minute demand data. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 10 © Hatch 2011/07 Table 3 Old Harbor Demand Summary Old Harbor Monthly Demand Summary (kW, kWh, gal) 15 Minute Demand Data Month Generation Peak Average Fuel Peak Average Jan-10 72,592 146 98 5,238 140 96 Feb-10 63,784 142 95 4,573 138 95 Mar-10 70,261 145 94 4,995 132 92 Apr-10 65,624 140 91 4,754 131 91 May-10 66,398 135 89 4,623 127 89 Jun-10 61,534 133 85 4,476 124 85 Jul-10 64,689 145 87 4,627 127 87 Aug-10 70,255 147 94 4,990 137 94 Sep-10 70,768 160 98 5,026 147 98 Oct-10 64,466 140 87 4,715 127 87 Nov-10 66,371 149 92 4,766 138 92 Dec-10 70,474 147 95 5,072 133 94 Total 807,216 160 92 57,855 50 60 70 80 90 100 110 120 130 140 150 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Hour of Day weekday weekend peak Figure 3 Old Harbor Average Daily Demand Fluctuations Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 11 © Hatch 2011/07 4.3 Hydrology The hydrology data used for the analysis is the median of the daily flow values for the East Fork of Mountain Creek published in the Mountain Creek Hydrology Report (Polarconsult, May 4, 2010). The report analyzes about 5 years of stream flow data measured from 7/14/1993 through 5/6/1996 (Alaska Department of Natural Resources) and from 6/15/1998 through 8/16/2000 (Polarconsult). The report compares the data with Kodiak rainfall and other USGS gauged streams. After comparison with USGS data, the report recommended adjustment factors be applied to the measured hydrology data based on a comparative analysis to the other gauge sites on Kodiak Island. The report also found flow measurements on Mountain Creek occurred during wetter (by about 20%) than normal rainfall years in Kodiak, AK. Based on those findings, this analysis uses the recommended adjustment factors with at least a 20% reduction in the summer and fall to account for the higher than normal precipitation. As stated in the May 2010 report, the conservative adjustments applied to the measured data can be adopted in lieu of performing additional flow measurements to confirm winter and spring low flows. The resulting adjusted hydrology data set is on par with a predicted hydrograph for Old Harbor in the absence of flow measurement data. However, it should be noted that real differences may exist between the Mountain Creek basin and the comparison basins as well as in the precipitation for Old Harbor compared with Kodiak. Such differences may prove that the 5 years of measured data on Mountain Creek is more representative of the long term average. For comparison purposes, this report presents an alternative analysis that does not use the adjustment factors. It is noted that the amount of useable energy from the hydroelectric development varies very little with either data set. The rationale for presenting an analysis using the measured data (unadjusted) as well as the adjusted data is in the event that excess energy utilization is considered. Given that the selection of project size is based on the presumption of additional energy utilization at some point, the unadjusted hydrology may assist in evaluating how much excess capacity would be available and the timing of such capacity. The accompanying charts show the hydrograph and flow duration curve for each hydrology scenario. The power potential axis on the hydrograph does not include the effects of changes in the dynamic head and efficiency of the turbine. The power production model discussed in the next section does include those dynamic variables as well as specific pipeline parameters for each alternative project configuration. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 12 © Hatch 2011/07 Table 4 Adjustment Factors for Measured Stream Flows at Intake Month 1 2 3 4 5 6 7 8 9 10 11 12 Adjustment 57% 56% 61% 74% 80% 80% 80% 68% 50% 55% 69% 53% Figure 4 Old Harbor Project Hydrograph and Approximate Power Potential Figure 5 Flow Duration Curve for the East Fork of Mountain Creek Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 13 © Hatch 2011/07 4.4 Power Production Power production is based on using both sets of daily hydrology data, above, and the various pipeline sizes and corresponding flow rates under consideration. Hydropower is then calculated daily taking into consideration friction, minor losses, and turbine efficiency at the given flow rate. Pipe diameter and thickness selection is based on the static pressure of the project with peak flow rates determined by constraining velocity in the pipeline to about 8.5 feet per second and limiting head loss to 15%. A nominal pipeline size of 18" results in the following selected pipe diameters and thicknesses along the project alignment. The increased pipe size in the first section of the project is required to prevent vacuum conditions during operation. Alternative size scenarios follow a similar pattern in pipe selection. Table 5 Pipe Selection Along Project Alignment Start Station End Station End Elevation Static Pressure Pipe OD Type Min SDR Selected SDR Thickness Pipe ID 0 1100 845 2 20 PE3608 32.5 26 0.769 18.46 1100 2200 835 6 20 PE3608 32.5 26 0.769 18.46 2200 3000 805 19 18 PE3608 32.5 26 0.692 16.62 3000 3500 730 52 18 PE3608 26.0 26 0.692 16.62 3500 4100 630 95 18 PE4710 21.0 21 0.857 16.29 4100 4500 585 115 18 PE4710 17.0 17 1.059 15.88 4500 5000 540 134 18 PE4710 15.5 15.5 1.161 15.68 5000 5500 520 143 18 PE4710 13.5 13.5 1.333 15.33 5500 6100 480 160 18 PE4710 13.5 13.5 1.333 15.33 6100 6500 495 154 18 PE4710 13.5 13.5 1.333 15.33 6500 7000 525 141 18 PE4710 13.5 13.5 1.333 15.33 7000 7500 505 149 18 PE4710 13.5 13.5 1.333 15.33 7500 7700 475 162 18 PE4710 11.0 11 1.636 14.73 7700 9500 275 249 16 steel 134.2 128 0.125 15.75 9500 10350 85 331 16 steel 100.8 64 0.250 15.50 Minor losses due to screens, valves, and bends are calculated in addition to the pipeline friction losses. The total minor loss factor, K, is 6.55. Other inefficiencies in the production of power include transformer and line losses of 2%, generator efficiency of 95%, and turbine peak efficiency of 89%. All of the scenarios ignore the potential gain in efficiency using dual turbines and are based on a single turbine operating at all times. Varying of efficiency versus flow rate is included in the analysis using the efficiency factors shown in the table. Shut off load for a single turbine is assumed to be 10% of rated capacity. The minimum flow at the intake is 2 cfs so multiple turbine configurations are not required to maintain year round operation for the project sizes analyzed. The following table shows the details of each project size evaluated. Turbine nameplate capacity will be slightly higher than the values in the table. % Power Turbine Efficiency 10% 63% 20% 78% 30% 85% 40% 87% 50% 89% 90% 89% 100% 87% Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 14 © Hatch 2011/07 Table 6 Pipe Diameters, Flows, Losses, and Power Output Base Pipe Diameter (in) Flow Rate (cfs) Headloss (ft) Peak Output (kW) 12 3.9 115 172 14 6.0 115 266 16 8.5 115 381 18 11.8 115 525 20 14.8 105 669 22 17.8 92 821 24 21.3 84 994 Conversion to potential energy includes evaluation of the dynamic head at each flow rate and the interpolation of turbine efficiency. Using the daily median flow values for the East Fork of Mountain Creek the following chart shows the annual potential energy output for various project sizes. Figure 6 Old Harbor Hydro Annual Energy Potential 4.5 Project Selection The 2010 annual energy demand in Old Harbor was approximately 810 MWh with a peak demand of 160 kW. All of the project sizes under consideration are able to offset about the same amount of Plant Capacity Plant Factor, Adjusted Plant Factor, Unadjusted 172 91% 99% 266 81% 92% 381 70% 84% 525 60% 76% 669 53% 68% 821 46% 62% 990 41% 55% Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 15 © Hatch 2011/07 diesel generation and provide about the same net benefit. Except for the smallest project considered, the alternatives include a significant amount of stranded plant. In lieu of determining how much of the surplus energy may be utilized, a simple unconstrained approach to selecting a project size is adopted that maximizes annual energy production with the least amount of initial cost and capacity. For the purpose of selecting a project, all the energy produced by the various configurations is assumed to have the same value. From this assumption, a relationship chosen to optimize the resource is to maximize the ratio of total energy produced per unit capacity to the cost per unit energy. This relationship is represented as kWh^2 / (capacity * cost). When this is done, as seen in the following chart, the adjusted hydrology data produces a flat area representing a range of projects that provide the best economic return with the 16" pipeline (381 kW) project being optimal. The optimal project for the unadjusted hydrology data utilizes an 18" pipeline (525 kW). The OPC provided with this report is for the 525 kW project which utilizes an 18" pipeline and approximately 11.8 cfs of flow. Figure 7 Project Optimization Chart Constructability aspects such as fusion machine capabilities (20" being a breakpoint) and the numerous bends favor the smaller range of pipe diameters whereas, operationally, the larger pipe diameters are preferable to reduce the dynamic pressure range at the turbine. Overall, the optimum project of 525 kW is reasonable from both an operational and constructability viewpoint. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 16 © Hatch 2011/07 5. Results 5.1 Cost Comparison Total cost of construction, including indirect costs, for all the project configurations are presented below. Table 7 Project Alternatives Comparison Pipe Size Installed Capacity, kW Potential Capacity, kW Installed Cost Potential Energy, kWh % Increase in Potential Energy % Increase in Installed Cost 12 172 172 $7,270,000 1,500,000 0% 0% 14 266 266 $7,510,000 2,150,000 43% 3% 16 381 381 $7,860,000 2,800,000 87% 8% 18 262 525 $7,970,000 3,470,000 131% 10% 20 335 669 $8,430,000 4,000,000 167% 16% 22 410 821 $8,780,000 4,430,000 195% 21% 24 497 994 $9,140,000 4,800,000 220% 26% It is evident from the table above that there is a large amount of fixed costs that are independent of project size. A relatively small incremental cost increase of 10% is associated with a more than doubling (131% increase) of the potential annual energy output. The cost of meeting Old Harbor base load requirements (160 kW) with the hydro project are relatively high, but the cost of obtaining surplus energy is very low. 5.2 Cost Detail The table below summarizes the OPC for the Hydroelectric Project. A more detailed estimate is included in Appendix A. Table 8 Opinion of Probable Cost Summary 525 kW Project with 50% Installed Capacity Item Labor Hours Labor Cost Equip Cost Materials Cost Ship Cost Total Cost PRECONSTRUCTION AND CONSTRUCTION SUPPORT $ 444,450 MOBILIZATION $ 423,000 POWERHOUSE $ 349,041 INTAKE $ 433,007 PIPELINE $ 981,278 ACCESS TRAIL $ 465,039 TURBINE AND GENERATOR INSTALLATION $ 166,300 ROADS, TAILRACE $ 425,889 TRANSMISSION $ 208,675 EQUIPMENT $ 614,900 SUBTOTAL, Contractor Direct Costs 18,218 $ 1,495,017 $ 644,900 $ 1,814,562 $ 557,100 $ 4,511,579 Weather delay (% of Labor and Equip) 5% $ 106,996 contingency 15% $ 676,737 contractor profit 15% $ 676,737 bonding 2% $ 90,232 SUBTOTAL, Construction Contract $ 6,062,280 SUBTOTAL, Owner Procurement, Turbine and Generator $ 640,000 Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 17 © Hatch 2011/07 Item Labor Hours Labor Cost Equip Cost Materials Cost Ship Cost Total Cost SUBTOTAL, Construction $ 6,702,280 construction finance interest $ 150,801 engineering 10% $ 649,400 inspection and testing 3% $ 217,200 owner admin 4% $ 250,000 TOTAL PROJECT $ 7,969,681 5.3 Project Benefits Calculation of the potential benefit gained from the hydro project involved determining how much diesel usage would occur during hydro operation. The unadjusted hydrology data set results in no diesel makeup energy required (the hydro would meet 100% of the existing demand requirement). The table below shows summarizes the project benefits. Table 9 Annual Fuel Savings with Hydro Project Existing Annual Generation 807,216 kWh Existing Annual Fuel Use 57,855 gal Fuel Price 4.08 $/gal Existing Annual Expenditures $235,911 Adjusted Hydrology Unadjusted Hydrology Annual Diesel Generation with Hydro 34,852 0 kWh Fuel Used 3,168 0 gal Cost $12,919 $0 Annual Fuel Savings with Hydro Project $222,992 $235,911 Displaced Diesel Fueled Generation 95% 100% Old Harbor's fuel consumption for diesel electric generation in 2010 was 57,855 gallons. The hydroelectric project would reduce fuel use by at least 95%. All of the project configurations analyzed result in the same benefit with regard to offsetting existing diesel generation. The high availability of the hydro project results in a significant amount of stranded plant. Evaluating possible uses and economic values of the surplus energy from the hydro will add to the overall economic benefit. The following charts, one for each hydrology scenario, show the expected daily potential hydro output and the expected amount of diesel generation with the hydro to meet current demand using the 525 kW hydro project. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 18 © Hatch 2011/07 Figure 8 Hydro Output (Adjusted Hydrology Data) and Diesel Generation Requirements Figure 9 Hydro Output (Unadjusted Hydrology Data) and Diesel Generation Requirements Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 19 © Hatch 2011/07 6. Economic Analysis 6.1 Diesel Integration As shown in Table 8, the expected annual fuel savings from the hydro project ranges from $222,992 to $235,911 depending on the actual hydrology. If the past hydrology measurements prove to be correct then the hydro project will displace about 100% of the current diesel generation. If the past hydrology measurements over represented actual runoff, then the amount of diesel generation displaced is expected to drop to about 95%. Because the hydro project and diesel plant may operate simultaneously at times, the amount of displaced diesel generation also depends on the configuration of the existing system. The smallest generator in the Old Harbor power plant is 235 kW. Using the adjusted hydrology set, the typical minimum output of the hydro project in the winter is about 90 kW. This is enough power to meet Old Harbor's average load but not the peak loads. Therefore a diesel generator must come online during the peak loading times to supply, on average, about an extra 22 kW. Under this scenario, the 235 kW diesel generator is operating at the desired minimum load rating of 10%. Efficiency at this low load is estimated to be 11 kWh/gal. 6.2 Economic inputs Operation and maintenance (O&M) costs can become a large part of the project economics over the long term. Several factors to consider include diesel engine repair and replacement, oil changes, hydro intake cleaning, repair, maintenance, and complying with the additional permitting requirements of the hydro project. Data for non fuel expenses related to diesel generation was obtained from AVEC PCE Annual Reports for the years 2008 through 2010 filed with the Regulatory Commission of Alaska. The reports include non fuel expenses for the entire AVEC system and therefore should be representative of annualized costs. Over the course of 2008-2010 the non fuel costs ranged from 0.096 $/kWh to 0.117 $/kWh with an average of 0.107 $/kWh. The cost are divided among 26 different accounts and a reduction factor was applied to each account to calculate reduced diesel non fuel expenses. Reduction factors ranged from 0% to 90% with the weighted average equal to 52%. The resulting non fuel cost for diesel with the hydro in operation is 0.056 $/kWh. O&M costs for the hydro project are estimated based on annualized costs and include 1.5% of the turbine cost for parts, $15,000 for FERC compliance and reporting, and $5,400 in miscellaneous engineering and permitting support. Labor associated with operating the hydro plant is accounted for in the existing diesel non fuel category by partial reduction of daily checks and other maintenance. A study by the University of Alaska Anchorage ISER in 2011 projects real fuel prices for 2011-2030 in individual communities in Alaska. The projected prices are in 2010 dollars and range from $4.08/gal in 2014 to $5.32/gal in 2030. For this analysis, the fuel price projection is extended to $5.52/gal in 2040 and flat from there on. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 20 © Hatch 2011/07 Like other major infrastructure projects, the hydro project has a very long project life. The project's economic life is assumed to be 50 years and all values are discounted to present day dollars using a 3% rate. The following tables summarize the economic inputs and first year results. Table 10 Economic Parameters Diesel Costs Fuel Price in 2014, First Year of Hydro ($/gal) 4.08 kWh Energy Generated, 2010 807,216 Fuel Used (gal) 57,855 Efficiency (kWh/gal) 13.95 Annual Fuel Cost $235,911 O&M rate ($/kWh) 0.10659 Current Annual O&M Costs $86,041 Total Diesel Annual Operational Cost, 2014 $321,952 Hydro Costs Initial Construction Cost $7,970,000 FERC Compliance and Reporting $15,000 Hydro O&M Cost Annual Parts (1.5% of turbine cost) $7,350 Labor (already inlcuded in Diesel non fuel) $0 Engineering (1 weeks/yr @ $135/hr) $5,400 Diesel O&M rate with Hydro ($/kWh) 0.05575 Diesel O&M Costs with Hydro $45,002 Total Annual O&M Costs with Hydro $72,752 Annual Diesel Usage with Hydro (gal) 3,168 Annual Fuel Cost with Hydro $12,919 Annual Displaced Diesel Fuel 54,687 Annual Fuel Savings $222,992 Combined Hydro and Diesel Annual Operational Cost $85,672 Annual Savings with Hydro $236,281 6.3 Economic Results Using the simplest economic analysis, the cost of the project divided by the annual savings provides a simple payback period. Using the total project cost, the annual savings results in a simple payback period of about 35 years. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 21 © Hatch 2011/07 Using a more detailed analysis, where costs are calculated annually and then discounted, results in a benefit to cost ratio ranging from 0.94 to 1.00. The results of the detailed economic analysis are summarized below. Table 11 Economic Summary Net Present Value (NPV) of Electrical Generation Costs Using Existing Diesel (Base) Using Hydro with Exist Diesel Adjusted Hydrology Unadjusted Hydrology Fuel $7,596,754 $416,023 $0 O&M $2,213,819 $1,871,899 $1,871,899 Total $9,810,573 $2,287,922 $1,871,899 Benefit $0 $7,522,651 $7,938,673 Capital Cost $0 $7,970,000 $7,970,000 Ratio 0.94 1.00 6.4 Sensitivity Analysis A sensitivity analysis of changes to the benefit to cost ratio due to varying demand and construction cost has been performed using the projected fuel prices, discount rate, and term above. The table below shows the Benefit to Cost Ratio (NPV Savings / Initial Cost) for various percent changes in the demand (applied to both the average and peak) and the construction cost. The sensitivity analysis is based on using the hydro with a new diesel and the adjusted hydrology. Table 12 Benefit to Cost Ratio Sensitivity Analysis % change in demand 0.93 -10% -5% 0% 5% 10% 15% 20% 25% 30% % change in cost -10% 0.9 1.0 1.0 1.1 1.1 1.2 1.2 1.2 1.3 -5% 0.9 0.9 1.0 1.0 1.1 1.1 1.1 1.2 1.2 0% 0.8 0.9 0.9 1.0 1.0 1.0 1.1 1.1 1.2 5% 0.8 0.8 0.9 0.9 1.0 1.0 1.0 1.1 1.1 10% 0.8 0.8 0.8 0.9 0.9 1.0 1.0 1.0 1.1 15% 0.7 0.8 0.8 0.8 0.9 0.9 0.9 1.0 1.0 20% 0.7 0.7 0.8 0.8 0.8 0.9 0.9 0.9 1.0 25% 0.7 0.7 0.7 0.8 0.8 0.8 0.9 0.9 0.9 30% 0.6 0.7 0.7 0.7 0.8 0.8 0.8 0.9 0.9 Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 22 © Hatch 2011/07 7. Conclusions and Recommendations 7.1 Conclusions The Old Harbor Hydroelectric Project has been investigated numerous times over the last two decades and has been actively pursued to the point of having a FERC license issued. A recurring result of the past work has been the high cost of the project as compared with the alternative of diesel generation. This investigation demonstrates that the project is still on the margin of being economical. However, the recognition of the secondary benefits and added security of locally generated energy weigh favorably for the hydro project and, while difficult to put into economic terms, are considered worthy of some additional cost. It is concluded that the Old Harbor Hydroelectric Project will prove to be a positive asset for the community and meet nearly all of the communities energy needs at a fixed cost. Once constructed, the benefits of the project will accrue for the indefinite future, and with the capacity to support additional growth, the project will result in a significant reduction in the cost of electrical energy generation in Old Harbor. 7.2 Recommendations The following recommendations are made: 1. Proceed with a project size using an 18" pipeline and a dual turbine configuration with only one 262 kW unit installed (50% of projects 525 kW capacity). An updated project description and analysis of environmental flows is included in Appendix D. 2. The near term demand growth can have a significant impact on the economics. It can also be an important consideration in selection of project size. Investigate the possible uses of surplus energy taking into consideration the timing of use. Revise project size recommendation as appropriate. 3. Continue with project development with a focus on obtaining financing, completing FERC licensing and permitting with the goal of minimizing post construction annual expenses, and proceeding with final design work for timely construction readiness. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page 23 © Hatch 2011/07 8. References Alaska Energy Authority, Alaska Energy Pathway 2010. ftp://ftp.aidea.org/2010AlaskaEnergyPlan/2010AlaskaEnergyReport.html Alaska Village Electric Cooperative, PCE Annual Reports for 2008, 2009, and 2010. Regulatory Commission of Alaska. Federal Energy Regulatory Commission, Final Environmental Assessment, Old Harbor Project P- 11690, June 26 2000. http://elibrary.ferc.gov:0/idmws/file_list.asp?document_id=3105779 Federal Energy Regulatory Commission, Order issuing original license re Alaska Village Electric Cooperative's Old Harbor Hydroelectric P-11690, December 12 2000. http://elibrary.ferc.gov:0/idmws/file_list.asp?document_id=2109984 Locher Interests LTD (with Harza Northwest and UAA ISER), Rural Hydroelectric Assessment and Development Study: Phase II Report, March 27, 1998, ADCRA Division of Energy. Polarconsult Alaska, Inc., Mountain Creek Hydrology Report, prepared for Alaska Village Electric Cooperative Inc., May 4, 2010. http://elibrary.ferc.gov/idmws/common/OpenNat.asp?fileID=12339741 Polarconsult Alaska, Inc., Project Maps, Prepared for Alaska Village Electric Cooperative, March 2 2010. http://elibrary.ferc.gov:0/idmws/file_list.asp?document_id=13800685 Polarconsult Alaska, Inc., Notice of Intent and Preliminary Application Document under P-13272, August 21 2009. http://elibrary.ferc.gov:0/idmws/file_list.asp?document_id=13748178 Solstice Alaska Consulting Inc., Proposed Study Plan, Old Harbor Hydroelectric Project, FERC Project P-13272, prepared for Alaska Village Electric Cooperative, January 4, 2010. http://elibrary.ferc.gov/idmws/common/OpenNat.asp?fileID=12339737 State of Alaska, Alaska Division of Community and Regional Affairs, Community Information Summaries, 2011. http://www.commerce.state.ak.us/dca/commdb/CF_CIS.htm University of Alaska Anchorage, Institute of Social and Economic Research (ISER), Alaska Fuel Price Projections 2011-2030, January 25, 2011. US Department of Labor, Bureau of Labor Statistics, Consumer Price Index, Fuel Oil, US City Average, Series ID CUSR0000SEHE01. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page A-1 © Hatch 2011/07 Appendix A Opinion of Probable Cost 525 kW Project with 50% Installed Capacity Old Harbor Hydroelectric ProjectReconnaissance and Feasibility StudyFinal ReportOld Harbor Hydroelectric ProjectEstimated Construction CostBase Labor Rate / hour 75 (includes directs, indirects, allowance for overtime & per diem)Super and specialist 95Work week 60 hoursNo. Labor HoursLaborRateLabor Cost Unit Cost Equip Cost Unit Unit Cost Materials Cost Unit Cost Ship CostPRECONSTRUCTION AND CONSTRUCTION SUPPORT$444,450Procurement, Submittals 2 3 wks 360 $95 $34,200 $34,200SWPP 1 2 wks 120 $95 $11,400 $11,400Survey 2 4 wks 480 $95 $45,600 $45,600Planning 1 2 wks 120 $95 $11,400 $11,400Construction Support 1 18 wks 1080 $95 $102,600 $102,600Asbuilt 1 1 wks 60 $95 $5,700 $5,700Mechanic 0.5 6 mos 810 $95 $76,950 $76,950Housing, Travellabor housing 720 Days $150 $108,000 $108,000contractor travel 54 trips $900 $48,600 $48,600MOBILIZATION$423,000Equipment transportlanding barge to Old Harbor 5 ea $7,500 $37,500 $37,500Operator 2 75 $75 $5,625 $5,625Laborer 2 75 $75 $5,625 $5,625Materials ShippingPipe 19 cont $6,000 $114,000 $114,000Jet Fuel 1 cont $6,000 $6,000 $6,000Building 4 cont $6,000 $24,000 $24,000Concrete 1 cont $6,000 $6,000 $6,000Diversion 3 cont $6,000 $18,000 $18,000Power Poles 2 cont $6,000 $12,000 $12,000Wire and Electrical 1 cont $6,000 $6,000 $6,000Turbine and Generator 1 cont $6,000 $6,000 $6,000Transformer, Switchgear 1 cont $6,000 $6,000 $6,000landing barge to Old Harbor 17 cont $7,500 $127,500 $127,500Demob Equipmentlanding barge to Old Harbor 5 ea $7,500 $37,500 $37,500Operator 2 75 $75 $5,625 $5,625Laborer 2 75 $75 $5,625 $5,625331POWERHOUSE$349,041sitework 400 cydconcrete and forms, building 104 cyd $200 $20,741 $20,741metal building shell 1200 sq ft $60 $72,000 $72,000architectural 1200 sq ft $20 $24,000 $24,000electrical, mechanical 1200 sq ft $20 $24,000 $24,000water, waste 1200 sq ft $20 $24,000 $24,000doors 1200 sq ft $10 $12,000 $12,000crane 1 ea $40,000 $40,000 $40,000Super 0.5 6 wks 180 $95 $17,100 $17,100Labor 3 6 wks 1080 $75 $81,000 $81,000Specialty 1 6 wks 360 $95 $34,200 $34,200Item CostDurationItemLabor Equipment MaterialShipping Total7/22/2011 Page A2 Old Harbor Hydroelectric ProjectReconnaissance and Feasibility StudyFinal ReportNo. Labor HoursLaborRateLabor Cost Unit Cost Equip Cost Unit Unit Cost Materials Cost Unit Cost Ship CostItem CostDurationItemLabor Equipment MaterialShipping Total332INTAKE$433,007coffer dam/construction diversion 1 ea $5,000 $5,000 $5,000impoundment structuresheet pile 420 sq ft $12 $5,040 $5,040concrete footing 11.1 cyd $400 $4,444 $4,444impoundment wall/spillway 50 ft $50 $2,500 $2,500flush gate 1 ea $5,000 $5,000 $5,000anchors 10 ea $1,000 $10,000 $10,000sealing 1 ea $2,000 $2,000 $2,000intake/desanderbase slab 4.7 cyd $400 $1,896 $1,896box structure 342 sq ft $50 $17,100 $17,100trashrack 1 ea $1,500 $1,500 $1,500screens 1 ea $2,000 $2,000 $2,000flush gate 1 ea $2,500 $2,500 $2,500insulation 342 sq ft $5 $1,710 $1,710access hatch/grating 1 ea $2,000 $2,000 $2,000air relief 1 ea $1,000 $1,000 $1,000transition to pipeline 1 ea $3,000 $3,000 $3,000concrete 7 cyd $400 $2,667 $2,667shut off gate 1 ea $2,500 $2,500 $2,500controls 1 ea $20,000 $20,000 $20,000equipment/storage shed 1 ea $5,000 $5,000 $5,000power line, communications 10350 ft $5.00 $51,750 $51,750Super 0.5 12 wks 360 $95 $34,200 $34,200Labor 4 12 wks 2880 $75 $216,000 $216,000Specialty 0.5 12 wks 360 $95 $34,200 $34,200332PIPELINE10350 ft $981,278HDPE 7700 ftSteel 2650 fthelicopter (includes fuel) 1 1 ea $180,000 $180,000 $180,000Labor 2 1.2 wks 145 $75 $10,850 $10,850hdpe 175,241 lb $1.20 $210,289 $210,289flange kits 4 ea $1,200 $4,800 $4,800drains/air reliefs 12 ea $500 $6,000 $6,000anchors 40 ea $1,200 $48,000 $48,000coated steel pipe 73,892 lb $1.50 $110,838 $110,838thrust block at powerhouse 1 ea $10,000 $10,000 $10,000intermediate thrust blocks 3 ea $3,000 $9,000 $9,000anchors 10 ea $2,000 $20,000 $20,000victaulic standard couplings 67 ea $1,300 $87,100 $87,100Super 0.5 12 wks 360 $95 $34,200 $34,200Labor 4 12 wks 2880 $75 $216,000 $216,000Specialty 0.5 12 wks 360 $95 $34,200 $34,2007/22/2011 Page A3 Old Harbor Hydroelectric ProjectReconnaissance and Feasibility StudyFinal ReportNo. Labor HoursLaborRateLabor Cost Unit Cost Equip Cost Unit Unit Cost Materials Cost Unit Cost Ship CostItem CostDurationItemLabor Equipment MaterialShipping Total332ACCESS TRAIL12000 ft $465,039Hydro ax operator 1 2.2 wks 133 $95 $12,667 $12,667geofabric 20000 sq yd $1.50 $30,000 $30,000culverts 10 ea $400 $4,000 $4,000shot rock 9000 cyd $15 $135,000 $135,000soil stabilization 20000 sq yd $0.50 $10,000 $10,000reseeding 20000 sq yd $0.50 $10,000 $10,000large culvert at gully 60 ft $100 $6,000 $6,000gate 1 ea $7,000 $7,000 $7,000rock blasting 1481 cyd $15.00 $22,222 $22,222Super 0.5 9 wks 270 $95 $25,650 $25,650Labor 5 9 wks 2700 $75 $202,500 $202,500333TURBINE AND GENERATOR INSTALLATION$166,300switchgear 1 ea $50,000 $50,000 $50,000transformer 1 ea $50,000 $50,000 $50,000main valve 1 ea $15,000 $15,000 $15,000Super 1 3 wks 180 $95 $17,100 $17,100specialty 2 3 wks 360 $95 $34,200 $34,200336ROADS, TAILRACE$425,889tailrace constructionstream channel construction 3000 ft $13.00 $39,000 $39,000bank stabilization 3000 ft $8.00 $24,000 $24,000embankment dike, south side pond 1000 ft $5.00 $5,000 $5,000fish access control or ph bypass option 1 ea $5,000 $5,000 $5,000culvert or concrete box from ph 30 ft $100 $3,000 $3,000Super 1 2 wks 120 $95 $11,400 $11,400Labor 3 2 wks 360 $75 $27,000 $27,000access road6200 ftclearing 5.7 acregeofabric 16533 sq yd $1.50 $24,800 $24,800shot rock 8267 cyd $15 $124,000 $124,000crushed or screened gravel 2756 cyd $25 $68,889 $68,889communications line 6200 ft $1.00 $6,200 $6,200signage 2 ea $1,500 $3,000 $3,000Super 1 3 wks 180 $95 $17,100 $17,100Labor 5 3 wks 900 $75 $67,500 $67,5007/22/2011 Page A4 Old Harbor Hydroelectric ProjectReconnaissance and Feasibility StudyFinal ReportNo. Labor HoursLaborRateLabor Cost Unit Cost Equip Cost Unit Unit Cost Materials Cost Unit Cost Ship CostItem CostDurationItemLabor Equipment MaterialShipping Total356TRANSMISSION$208,675overhead transmission line 1.46 mipoles, foundations, and hardware 52 ea $2,000 $104,000 $104,000wire 23100 ft $1.25 $28,875 $28,875guys/anchors 26 ea $700 $18,200 $18,200Super 1 3 wks 180 $95 $17,100 $17,100Labor 3 3 wks 540 $75 $40,500 $40,500EQUIPMENT$614,900fusion machine 1 5 mo $15,000 $75,000 $75,0004 wheelers 4 1 ea $9,000 $36,000 $36,0001/3 yard mixer 1 6 mo $1,000 $6,000 $6,000mix truck 1 6 mo $5,500 $33,000 $33,000small generator 2 1 ea $2,000 $4,000 $4,000large generator 2 6 mo $2,000 $24,000 $24,000loader 1 8 mo $7,000 $56,000 $56,000excavator 2 5 mo $6,000 $60,000 $60,000end dump 1 6 mo $4,500 $27,000 $27,000rock hammer 1 6 mo $1,000 $6,000 $6,000flatbed truck 2 6 mo $800 $9,600 $9,600trackhauler (marooka) 3 5 mo $3,500 $52,500 $52,500dozer 1 6 mo $4,000 $24,000 $24,000hydro ax 1 2 mo $5,000 $10,000 $10,000fuel 30000 gal $5.00 $150,000 $150,000air compressor 1 6 mo $800 $4,800 $4,800air track drill 1 6 mo $2,000 $12,000 $12,000miscellaneous tools 1 1 ea $25,000 $25,000 $25,000SUBTOTAL, Contractor Direct Costs 18,218 $1,495,017 $644,900 $1,814,562 $557,100 $4,511,579Weather delay (% of Labor and Equip) 5% $106,996contingency 15% $676,737contractor profit 15% $676,737bonding 2.0% $90,232SUBTOTAL, Construction Contract $6,062,280333OWNER PROCURED TURBINE AND GENERATORturbine and generator 1 ea $490,000 $490,000 $490,000controls 1 ea $150,000 $150,000 $150,000SUBTOTAL, Owner Procurement, Turbine and Generator $640,000SUBTOTAL, Construction $6,702,280construction finance interest 2.25% $150,801engineering 9.7% $649,400inspection and testing 3.2% $217,200owner admin 3.7% $250,000TOTAL PROJECT$7,969,6817/22/2011 Page A5 Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page B-1 © Hatch 2011/07 Appendix B Construction Schedules Task NameStartFinishFERC License Application Submitted1/23/121/23/12FERC License Issued1/17/131/17/13Grant/Funding Available7/2/127/2/12Plans/Procurement Documents10/19/1210/19/12Construction Contract Awarded1/17/131/17/13Procurement - Turbine (Owner)1/17/131/17/13Procurement - Pipe, Bldg, Materials2/16/132/16/13Equipment Mobilization5/6/135/11/13Quarry Development5/11/135/25/13Material Mobilization5/17/136/7/13Access Road Grading/Clearing5/11/135/18/13Access Road Construction5/25/136/8/13Pipeline Trail Clearing5/18/135/25/13Pipeline Trail Construction5/25/137/27/13Pipeline Construction7/27/1310/19/13Intake7/27/1310/19/13Powerhouse6/8/137/20/13Tailrace7/13/137/27/13Powerline6/8/136/29/13Turbine Installation11/13/1311/20/13Startup/Testing11/20/1312/4/13Demob Equipment10/19/1310/26/131/17/20131/17/20131/17/20132/16/2013JanFebMarAprMayJunJulAugSepOctNovDecQtr 1, 2013Qtr 2, 2013Qtr 3, 2013Qtr 4, 2013TaskSplitProgressMilestoneSummaryProject SummaryExternal TasksExternal MilestoneDeadlineSingle Season Construction Schedule Old Harbor Hydroelectric ProjectReconnaissance and Feasibility StudyFinal Report7/20/11 Page B-2Project: Project1Date: 7/20/11 Task NameStartFinishFERC License Application Submitted6/29/126/29/12FERC License Issued6/24/136/24/13Grant/Funding Available7/2/127/2/12Plans/Procurement Documents3/26/133/26/13Construction Contract Awarded6/24/136/24/13Procurement - Turbine (Owner)6/24/136/24/13Procurement - Pipe, Bldg, Materials7/24/137/24/13Equipment Mobilization8/8/138/13/13Quarry Development8/13/138/27/13Material Mobilization5/18/146/8/14Access Road Grading/Clearing8/13/138/20/13Access Road Construction8/27/139/10/13Pipeline Trail Clearing8/20/138/27/13Pipeline Trail Construction8/27/135/27/14Pipeline Construction6/8/148/31/14Intake5/27/148/17/14Powerhouse6/8/147/20/14Tailrace7/13/147/27/14Powerline6/8/146/29/14Turbine Installation8/31/149/7/14Startup/Testing9/7/149/21/14Demob Equipment8/31/149/7/146/24/20136/24/20136/24/20137/24/2013JunJulAugSepOctNovDecJanFebMarAprMayJunJulAugSepOctQtr 3, 2013Qtr 4, 2013Qtr 1, 2014Qtr 2, 2014Qtr 3, 2014Qtr 4, TaskSplitProgressMilestoneSummaryProject SummaryExternal TasksExternal MilestoneDeadlineTwo Season Construction Schedule Old Harbor Hydroelectric ProjectReconnaissance and Feasibility StudyFinal Report7/20/11 Page B-3Project: Project1Date: 7/20/11 Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page C-1 © Hatch 2011/07 Appendix C Project Drawings Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page D-1 © Hatch 2011/07 Appendix D Project Description Alaska Village Electric Cooperative (AVEC), the electric utility provider in Old Harbor, Alaska is seeking to develop a hydroelectric resource near the community of Old Harbor on Kodiak Island. Old Harbor is accessible by small airplanes and boats. Old Harbor is located about 50 miles southwest of Kodiak, AK. The intake is located at about 57°14.7' N and 153°20.7' W at an elevation of about 850'. The powerhouse is located at about 57°14.0' N and 153°18.4' W at an elevation of about 85'. The project diversion and intake works will consist of a concrete, or other suitable material, for a diversion/cut off weir with integral spillway. The height of the weir will be approximately 4-6 feet with a length across the creek and floodplain valley of about 100'. A water filtering system consisting of a trash rack and/or coanda screens, diversion gates, and secondary screens will be incorporated into the weir structure as a separate desanding box that will be partially exposed above grade. A below grade transition with an above ground air relief inlet pipe will convey water to a buried High Density Polyethylene Pipe (HDPE) pipeline. The pipeline consists of buried HDPE pipe with diameters of 18" to 20" and buried steel pipe with a diameter of 16". A total of 7,700' of HDPE and 2,650' of steel pipe will be installed along a constructed access trail. The access trail will consist of a 12' wide rock fill about 1' to 2' deep placed over a geo-textile filter fabric. Rock cuts and fill will be required in areas of significant terrain and cross slopes. The trail also includes culverts and an access gate. The powerhouse is expected to be a 25' by 35' metal building or similar structure to house the two turbines and associated equipment, switchgear, controls, and tools. The building height is expected to be about 12'. A new 24' wide access road constructed of 2' of rock over a geo-textile will extend from the existing water tank access road to the powerhouse. The 7.2 kV 3 phase overhead transmission line will follow the access road alignment. The power generation equipment will consist of two 262 kW units with a 480 V generator and switchgear for each unit. Only one unit will initially be installed. Each unit will have a hydraulic capacity of 5.9 cfs for a total project peak flow rate of 11.8 cfs capable of producing 525 kW of power. A bypass flow system for maintaining environmental flows, if any are required, is not proposed at this time. A tailrace structure and culvert or constructed stream bed will convey the project flows to the nearby unnamed lake (swimming pond). A constructed tailrace stream or culvert will convey project flows from the unnamed lake to the headwaters of the Lagoon Creek Tributary. The project is a run-of-river hydro that will be operated automatically and primarily in standalone mode as the communities primary source of electrical generation. Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page D-2 © Hatch 2011/07 The following is a summary description of the project components. Estimated dependable capacity of 130 kilowatts (kW). Project peak capacity of 525 kW utilizing 11.8 cfs of water with a static head of 765'. Initial installed capacity of 262 kW utilizing up to 5.9 cfs of water. A 6' high by 100' long cut off (diversion) wall that will not create any significant impoundment of water. A 10,350' long pipeline consisting of 7,700' of 18" and 20" HDPE pipe and 2,650' of 16" steel pipe. A 12' wide, 11,700' long (approximate) intake access trail. A single 262 kW Pelton turbine with a hydraulic capacity of 5.9 cubic feet per second (cfs) coupled directly to a 480 volt, 3 phase generator with a provision for a second 262 kW turbine. A 25'x35' (approximately 900 square-foot) powerhouse. A culvert or constructed stream tailrace into a lake and subsequent lowlands with final discharge to the Lagoon Creek Tributary. A 7,700' long (1.5 mile), 7.2 kV three phase overhead power line. A 24' wide, 6,200' long access road. Project Flow Diversion Based on the demand profile in 2010, the following chart and table provide predicted diversion flows resulting from project operation. The operation is based on a flat daily total output about 10 kW higher than peak daily demand with a load controller absorbing and releasing loads to handle daily fluctuations. Table 13 - Monthly Average Mountain Creek In-stream Flow and Diversion Potential (cfs) Monthly Average Mountain Creek In-stream Flow and Diversion Potential (cfs) Month Avg Existing Flow at Intake Avg Maximum Potential Diverted by Project Avg Diverted based on 2010 Demand 1 3.0 3.0 2.6 2 2.2 2.2 2.2 3 2.5 2.5 2.1 4 3.1 3.1 2.4 5 11.1 9.3 2.5 6 40.6 11.8 2.5 7 19.2 11.5 2.5 8 8.9 7.8 2.6 9 10.9 8.7 2.7 10 8.7 8.4 2.5 11 9.8 8.1 2.6 12 3.9 3.9 2.6 Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page D-3 © Hatch 2011/07 Figure 10 Chart of Mountain Creek In-stream Flow and Diversion Potential (cfs) Project Operational Flow 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 1/1 2/20 4/10 5/30 7/19 9/7 10/27 12/16 Date Mountain Creek Existing Flow Diverted Flow for Energy, 2010 Demand Based Maximum Potential Flow Diversion Old Harbor Hydroelectric Project Reconnaissance and Feasibility Study Final Report ISO 9001 Page E-1 © Hatch 2011/07 Appendix E Mountain Creek Hydrology Report, Old Harbor, Alaska POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4,2010 PAGE 1 M OUNTAIN C REEK H YDROLOGY R EPORT O LD H ARBOR , A LASKA May 4, 2010 prepared by polarconsult alaska, inc. 1503 West 33rd Avenue, Suite 310 Anchorage, Alaska 99503 Phone: (907) 258-2420 prepared for ALASKA VILLAGE ELECTRIC COOPERATIVE 4831 Eagle Street Anchorage, Alaska 99503 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE I TABLE OF CONTENTS 1. INTRODUCTION......................................................................................................................... 1 2. PURPOSE...................................................................................................................................... 1 3. METHODOLOGY........................................................................................................................ 1 4. EXISTING DATA.......................................................................................................................... 3 4.1. EAST FORK OF MOUNTAIN CREEK ............................................................................................ 3 4.2. USGS DATA FOR KODIAK ISLAND ............................................................................................ 3 5. COMPARATIVE ANALYSIS........................................................................................................ 6 5.1. CORRELATION WITH KODIAK RAINFALL DATA ........................................................................... 6 5.2. CORRELATION WITH USGS DATA SETS ..................................................................................... 7 6. ADJUSTMENTS AND FINAL HYDROGRAPH.......................................................................... 9 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 1 1. Introduction As part of updated feasibility study and conceptual design for the Old Harbor Hydroelectric Project, Polarconsult undertook a review of the hydrology data to identify whether the data was sufficient to quantify the economic benefits of the hydroelectric project. Additionally, there have been recent study requests by resource agencies in the Federal Energy Regulatory Commission (FERC) licensing process for additional information on the hydrology. The resource agencies seek to quantify the amount of water for the purpose of both economic and fishery resource evaluation. Figure 1 shows the location of the proposed hydroelectric project and the Mountain Creek drainage. 2. Purpose This report provides a summary and analysis of the hydrology data collected on the East Fork of Mountain Creek. The purpose of this analysis is to: 1. Determine the water quantity from the East Fork of Mountain Creek for hydroelectric production, and 2. Whether additional data collection efforts should be performed for the purpose of quantifying water supply for hydroelectric production. The analysis associated with the first goal is a review and, if necessary, adjustment of the existing data to provide a reasonably confident estimate of water quantity at the intake site on the East Fork of Mountain Creek. This is done using a comparative analysis of the East Fork of Mountain Creek with other know stream flow data sets on Kodiak Island. The work associated with the second goal is to perform a risk assessment on the estimated water quantity for providing hydroelectric power for the community of Old Harbor and a recommendation on whether additional hydrology data should be collected. This is done by looking at the impacts to the benefits of the hydro project with the uncertainties in the hydrograph for Mountain Creek. 3. Methodology The steps to arrive at the recommended hydrograph for Old Harbor are summarized below: 1. AKDNR data was scaled by the relative basin area of the East Fork of Mountain Creek. 2. The Polarconsult data was aggregated with the AKDNR data and a daily median per basin square mile was calculated. 3. All USGS data sets were collected for Kodiak Island. Data from Terror Lake and River and sites with less than 500 records were excluded. 4. A daily median per basin square mile was calculated for each data set. 5. A daily mean and median was calculated from the aggregate of all USGS medians per basin square mile. 6. The aggregated Mountain Creek data was scaled to more closely fit USGS data. POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 2 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 3 4. Existing Data 4.1. East Fork of Mountain Creek The data for stream flow on the East Fork of Mountain Creek is collected from the Alaska Department of Natural Resources, Division of Mining and Water Management, Alaska Hydrologic Survey, October 1996 Final Report, "Old Harbor Stream Gaging Project". The AKDNR gaged Mountain Creek just below the East and West fork confluence. The elevation at this location is approximately 490' and the drainage area is about 4.6 square miles. The data set begins on 7/14/1993 and extends through 5/6/1996 giving a total of 921 records. This data has been scaled by the East Fork sub basin percentage to arrive at a presumed data set for the East Fork. While not exactly data from the East Fork, the AKDNR installed a gage on the East Fork concurrently with this gage from 10/17/1995 through 5/6/1996. The correlation in stage and flow measurements from the two locations indicated that scaling the lower gage site data to the East Fork is reasonable. The stream flow data set that was actually collected at the intake comes from the licensing effort performed by Polarconsult. This data set begins on 6/15/1998 and extends through 8/16/2000 consisting of 794 daily records in total. Five stage discharge points were used to develop the stage discharge relationship. The data collected is presented in the Appendix. When combined with the existing AKDNR data, there are a total of 1715 daily records that have been aggregated to daily median values to compare with the USGS data sets. 4.2. USGS Data for Kodiak Island Table 1 lists all of the available data sets from the USGS for Kodiak Island. Only data sets with at least 500 records are used in the comparative analysis. The location of the gage sites is shown USGS Gage Location Map in the Appendix. Each USGS data set was sorted by day and then analyzed to provide the median flow value for each day. This was then divided by the drainage area to arrive a median flow per square mile. The median method of aggregating the data for each day is chosen because the distribution of the data is not normal. It is more typical of a lognormal or gamma distribution. This method of comparison excludes large runoff events from storms skewing the average. Figure 1 shows the resulting median daily flows per square mile for each of the USGS sites. A large amount of variability exists even though the gaged basins are relatively close together. This is due to a noticeable trend towards decreasing precipitation on Kodiak Island when going from the southeast coast to the northwest coast. However, the USGS data exhibits much less variability during the winter and spring low flows which are, at present, the most critical flows when analyzing the Old Harbor Hydroelectric Project economics because those are the lowest flows that occur during the year. POLARCONSULTALASKA, INC. MOUNTAINCREEKHYDROLOGYREPORTOLDHARBOR, AKMAY4, 2010 PAGE4Table 1 - USGS Stream Gage Sites on Kodiak IslandUSGS Site Number Site NameDecimalLatitudeDecimalLongitudeGaugeAltitudeDrainageAreaBeginningof RecordEnd of RecordNumber of Records15295500L KITOI C NR AFOGNAK AK58.1951-152.3670152.610/1/19609/30/196136515295600TERROR R NR KODIAK AK57.6506-153.0320123015.06/20/19629/30/1986530915295700TERROR R AT MOUTH NR KODIAK AK57.6940-153.16403030.71/8/196410/9/20071119315296000 UGANIK R NR KODIAK AK 57.6843 -153.4220 20 123.0 4/11/1951 9/30/1978 999415296300 SPIRIDON LK OUTLET NR LARSEN BAY AK 57.6771 -153.6520 440 23.3 5/23/1962 7/15/1965 115015296480 LARSEN BAY C NR LARSEN BAY AK 57.5151 -153.9880 800 3.9 8/22/1980 9/30/1984 150115296500FALLS C NR LARSEN BAY AK57.2742-153.98603805.77/25/19749/30/197543315296520 CANYON C NR LARSEN BAY AK 57.2826 -153.9830 450 8.8 7/25/1974 9/30/1976 79915296550 UPPER THUMB R NR LARSEN BAY AK 57.3501 -153.9700 380 18.8 7/27/1974 9/30/1982 298815296600 KARLUK R AT OUTLET NR LARSEN BAY AK 57.4429 -154.1140 360 100.0 8/21/1975 9/30/1982 186815296950AKALURA C AT OLGA BAY AK57.1659-154.22902018.48/22/19759/30/197640615297000DOG SALMON C NR AYAKULIK AK57.2076-154.073035072.912/10/19599/30/196148915297100 HIDDEN BASIN C NR PORT LIONS AK 57.5942 -153.0150 1500 3.0 8/1/1982 1/31/1984 54915297110HIDDEN BASIN C NR MOUTH NR KODIAK AK57.5626-152.961020011.93/1/19831/31/198433715297200 MYRTLE C NR KODIAK AK 57.6026 -152.4060 20 4.7 5/22/1963 9/30/1986 853315297450 MF PILLAR C NR KODIAK AK 57.7987 -152.4520 175 2.0 10/1/1968 5/31/1970 60815297470 MONASHKA C NR KODIAK AK 57.8420 -152.4480 20 5.5 6/25/1972 9/30/1976 155915297482FALLS C NR PORT LIONS AK57.6681 -152.9360 1500 4.3 10/1/1980 9/30/1983 109515297485 KIZHUYAK R NR PORT LIONS AK 57.7098 -152.8710 15 47.5 4/1/1980 9/30/1994 5296E FORK MOUNTAIN C (COMBINED) 57.2450 -153.3442 840 1.8 7/14/1993 8/16/00 1715Notes:Strikeout gage stations excluded in analysis because of small number of records. POLARCONSULTALASKA, INC. MOUNTAINCREEKHYDROLOGYREPORTOLDHARBOR, AKMAY4, 2010 PAGE5Figure 10.010.020.030.040.050.060.01/1 1/31 3/2 4/1 5/2 6/1 7/2 8/1 9/1 10/1 11/1 12/1Day of YearUnit Flow (cfs/ sq mi)UGANIK R NRSPIRIDON LKLARSEN BAY CANYON C NRUPPER THUMBKARLUK R ATHIDDEN BASIMYRTLE C NRMF PILLAR CMONASHKA C FALLS C NR KIZHUYAK R East Fork Mountain POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 6 5. Comparative Analysis 5.1. Correlation with Kodiak Rainfall Data Rainfall in Kodiak showed a strong correlation with the runoff data collected in Old Harbor during the summer of 1998. This correlation is shown in the following chart. The entire Kodiak rainfall record is shown in the chart below. The wettest year of record occurred in 1998. Thus the limited hydrology data collected on Mountain Creek is probably slightly skewed to indicate more runoff than average. In fact, the average total rainfall for the years 1993 through 1996 and 1998 through 2000 is 80" versus the average for the period of record which is 65". Thus, the observed runoff may actually need to be adjusted down by about 20%. Summer 1998 Old Harbor Project Stream Flows 0 20 40 60 80 100 120 140 160 180 6/17 6/24 7/1 7/8 7/15 7/22 7/29 8/5 8/12 8/19 8/26 9/2 9/9 9/16 9/23 9/30 10/7 DateFlow (cfs)0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Rainfall (in)Mountain Creek, Canyon Intake Mountain Creek, Mouth Kodiak Rainfall (in) Kodiak Rainfall Data 0 20 40 60 80 100 120 1931 1941 1951 1961 1971 1981 1991 2001 YearRainfall (in)0 50 100 150 200 250 300 350 400 Number of Observationsrainfall (in) daily count POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 7 5.2. Correlation with USGS Data Sets The comparison of the East Fork Mountain Creek data with the combined USGS data sets shows that the Mountain Creek data set has higher than average flows year round but is still within the range of the observed USGS gage site data. The most significant deviation appears to be summer flows that are quite higher than average for all of the USGS basins as shown in Figure 1. Table 2 gives an indication as to a likely reason this. The Mountain Creek intake is located at a fairly high elevation. Three other USGS gage sites are at similar elevations - Larsen Bay Creek, Hidden Basin Creek, and Falls Creek. Larsen Bay Creek is noticeably drier mainly due to its location on the middle northwest coast, which puts it in the lee of the predominant flow pattern across the island. The other two locations exhibit significantly higher than average summer flows. Therefore, it is not unexpected that Mountain Creek has higher than average summer flows as well. Fall flows at Mountain Creek represent the second highest when included in the USGS data set. The location of Mountain Creek, near the highest peaks on the southeast coast is certainly a reasonable explanation for the high rates of runoff during fall because of the predominant flow pattern coming in from the Pacific Ocean and the high altitude of the basin. The most concerning aspect of the Mountain Creek data set is the higher than average winter flows. Mountain Creek ranks 3rd out of the 12 USGS sites and is 33% higher than the average. The disparity is especially apparent when it is observed that the highest winter producing gage sites are very near sea level. Given that both the AKDNR and Polarconsult rating curves lacked low flow resolution it seems that the most likely reason for the unusually high winter flows is a deficient rating curve in the low flow readings. In other words, the Mountain Creek data set should have winter time flows that are closer to the average of the USGS sites. POLARCONSULTALASKA, INC. MOUNTAINCREEKHYDROLOGYREPORTOLDHARBOR, AKMAY4, 2010 PAGE8Table 2 - Seasonal Average Unit FlowsUSGS Site Number Site NameGaugeAltitudeDrainageArea Jun-Aug Sep-Nov Dec-Mar Apr-MayAnnualAverage15296000 UGANIK R NR KODIAK AK 20 123.0 10.1 3.7 1.1 4.1 4.515296300 SPIRIDON LK OUTLET NR LARSEN BAY AK 440 23.3 2.1 1.9 1.9 2.7 2.115296480 LARSEN BAY C NR LARSEN BAY AK 800 3.9 2.1 2.2 1.5 3.5 2.215296520 CANYON C NR LARSEN BAY AK 450 8.8 7.7 5.7 1.3 4.6 4.615296550 UPPER THUMB R NR LARSEN BAY AK 380 18.8 6.5 4.2 1.7 4.8 4.115296600 KARLUK R AT OUTLET NR LARSEN BAY AK 360 100.0 4.3 3.8 1.9 3.2 3.215297100 HIDDEN BASIN C NR PORT LIONS AK 1500 3.0 31.4 7.8 1.5 7.8 11.615297200 MYRTLE C NR KODIAK AK 20 4.7 6.3 6.3 3.4 9.2 5.815297450 MF PILLAR C NR KODIAK AK 175 2.0 6.4 9.0 4.1 10.1 6.915297470 MONASHKA C NR KODIAK AK 20 5.5 8.4 5.6 2.1 10.7 6.015297482 FALLS C NR PORT LIONS AK 1500 4.3 23.9 6.5 1.9 6.5 9.315297485 KIZHUYAK R NR PORT LIONS AK 15 47.5 8.4 3.6 2.7 4.1 4.6E FORK MOUNTAIN C 840 1.8 15.6 8.3 2.8 6.2 7.9Average 9.8 5.0 2.1 5.9 5.4 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 9 6. Adjustments and Final Hydrograph Based on the comparison above and the known lack of stage discharge measurements below 6cfs for the AKDNR data (40% of 15cfs) and 10cfs for the Polarconsult data it is recommended that the existing Mountain Creek data should be adjusted to match the USGS for during winter months. Although only the winter data appears to require an adjustment, we recommend that all of the data be adjusted down to a varying degree to account for the lack of a longer term and more focused effort to obtain stream flow data on Mountain Creek. The adjustments made bring the data set more in line with the average of the USGS data sets. While this is a conservative approach, it is reasonable to opt for this reduced data set in lieu of performing additional streamflow measurements. The following table shows the adjustments applied to the monthly averages of the Mountain Creek data. Table 3 - Mountain Creek Adjustments to Mean Monthly Unit Flows Month USGS Mean USGS Median Mountain Creek Mean Adjustment Factor Adjusted Mean 1 2.0 1.7 3.0 57% 1.70 2 1.8 1.5 2.7 56% 1.50 3 1.8 1.5 1.8 61% 1.10 4 2.9 2.2 2.7 74% 2.00 5 9.0 6.7 9.6 93% 9.00 6 14.6 11.4 25.9 85% 22.00 7 10.5 6.2 14.1 85% 12.00 8 4.4 2.9 6.7 68% 4.50 9 5.8 4.4 11.0 50% 5.50 10 5.2 4.3 9.1 55% 5.00 11 4.0 3.1 4.6 69% 3.20 12 2.8 2.2 3.8 53% 2.03 Figure 2 shows the final recommended unit hydrograph with the median and average of the USGS data sets included and Figure 3 shows the final recommended hydrograph at the intake site of Mountain Creek. POLARCONSULTALASKA, INC. MOUNTAINCREEKHYDROLOGYREPORTOLDHARBOR, AKMAY4, 2010 PAGE10 Figure 2 - Mountain Creek Adjusted Unit Flows Compared with USGS Mean and Median0.010.020.030.040.050.060.01/1 1/31 3/2 4/1 5/2 6/1 7/2 8/1 9/1 10/1 11/1 12/1Day of YearUnit Flow (cfs/sq mi)USGS MeanUSGS MedianAdjusted Unit Flow POLARCONSULTALASKA, INC. MOUNTAINCREEKHYDROLOGYREPORTOLDHARBOR, AKMAY4, 2010 PAGE11Figure 3 - Final Hydrograph and Power Output for Old Harbor Hydroelectric Project0.05.010.015.020.025.030.035.040.045.050.01/1 1/31 3/2 4/1 5/2 6/1 7/2 8/1 9/1 10/1 11/1 12/1Day of YearMedian Stream Flow (cfs)050100150200250300350Power Output (kW)Final Recommended FlowPower Output POLARCONSULTALASKA, INC. MOUNTAINCREEKHYDROLOGYREPORTOLDHARBOR, AKMAY4, 2010 PAGE12If constructed and operated at full potential year round, the project would have the following impact on median flows at the canyon of Mountain Creek.0.05.010.015.020.025.030.035.040.045.050.01/1 1/31 3/2 4/1 5/2 6/1 7/2 8/1 9/1 10/1 11/1 12/1Day of YearMedian Stream Flow (cfs)0%10%20%30%40%50%60%70%80%90%100%% Reduction in Moutain Creek Flows at CanyonWater Use for HydroCanyon Mountain Creek Median Flows% Reduction in Canyon Mountain Creek Flows POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 13 APPENDIX Polarconsult Mountain Creek Stream Gage Data 7 Pages USGS Gage Location Map 1 Page POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 14 STAGE DISCHARGE DATA Location Date Recorder Depth Flow intake 8/16/2000 0.78 10.6 intake 6/3/1999 1.18 24.8 intake 10/7/1998 0.82 11.7 intake 8/14/1998 0.8 9.5 intake 6/15/1998 1.42 45.3 y = 1.6207e2.335x R2 = 0.9897 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Depth (ft)Discharge (cfs) POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 15 POLARCONSULT EAST FORK MOUNTAIN CREEK FLOW DATA Date Flow 6/15/1998 43.31 6/16/1998 46.78 6/17/1998 53.26 6/18/1998 51.06 6/19/1998 50.63 6/20/1998 53.83 6/21/1998 53.16 6/22/1998 47.69 6/23/1998 42.47 6/24/1998 38.76 6/25/1998 40.52 6/26/1998 44.03 6/27/1998 50.02 6/28/1998 56.96 6/29/1998 68.08 6/30/1998 67.84 7/1/1998 57.28 7/2/1998 49.65 7/3/1998 63.23 7/4/1998 54.00 7/5/1998 42.50 7/6/1998 36.30 7/7/1998 31.58 7/8/1998 27.54 7/9/1998 25.35 7/10/1998 24.57 7/11/1998 23.52 7/12/1998 24.05 7/13/1998 27.34 7/14/1998 29.93 7/15/1998 32.49 7/16/1998 30.66 7/17/1998 27.45 7/18/1998 24.00 7/19/1998 21.30 7/20/1998 24.54 7/21/1998 71.42 7/22/1998 59.30 7/23/1998 44.24 7/24/1998 35.39 7/25/1998 32.05 7/26/1998 31.37 7/27/1998 28.96 7/28/1998 25.90 Date Flow 7/29/1998 22.71 7/30/1998 21.29 7/31/1998 21.20 8/1/1998 20.66 8/2/1998 19.67 8/3/1998 18.78 8/4/1998 17.57 8/5/1998 16.18 8/6/1998 14.73 8/7/1998 14.49 8/8/1998 14.58 8/9/1998 14.03 8/10/1998 13.11 8/11/1998 12.24 8/12/1998 11.43 8/13/1998 10.74 8/14/1998 10.35 8/15/1998 9.90 8/16/1998 9.66 8/17/1998 9.29 8/18/1998 9.27 8/19/1998 9.08 8/20/1998 9.17 8/21/1998 8.89 8/22/1998 8.54 8/23/1998 8.29 8/24/1998 8.15 8/25/1998 7.95 8/26/1998 7.64 8/27/1998 7.48 8/28/1998 7.36 8/29/1998 7.32 8/30/1998 7.66 8/31/1998 9.58 9/1/1998 10.40 9/2/1998 14.07 9/3/1998 19.36 9/4/1998 19.32 9/5/1998 18.39 9/6/1998 16.62 9/7/1998 14.67 9/8/1998 13.06 9/9/1998 12.14 9/10/1998 14.63 Date Flow 9/11/1998 14.98 9/12/1998 18.08 9/13/1998 17.90 9/14/1998 15.54 9/15/1998 13.49 9/16/1998 12.05 9/17/1998 11.29 9/18/1998 11.85 9/19/1998 25.09 9/20/1998 58.77 9/21/1998 44.18 9/22/1998 30.31 9/23/1998 23.10 9/24/1998 19.28 9/25/1998 17.16 9/26/1998 15.61 9/27/1998 14.56 9/28/1998 13.48 9/29/1998 12.77 9/30/1998 11.92 10/1/1998 11.05 10/2/1998 10.33 10/3/1998 9.80 10/4/1998 10.26 10/5/1998 10.27 10/6/1998 10.26 10/7/1998 10.90 10/8/1998 11.44 10/9/1998 11.00 10/10/1998 10.51 10/11/1998 9.78 10/12/1998 10.00 10/13/1998 9.56 10/14/1998 9.25 10/15/1998 9.63 10/16/1998 10.33 10/17/1998 10.82 10/18/1998 11.54 10/19/1998 13.35 10/20/1998 15.49 10/21/1998 16.76 10/22/1998 17.67 10/23/1998 16.20 10/24/1998 15.12 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 16 Date Flow 10/25/1998 14.15 10/26/1998 14.50 10/27/1998 14.84 10/28/1998 14.17 10/29/1998 13.33 10/30/1998 12.51 10/31/1998 12.08 11/1/1998 13.23 11/2/1998 16.88 11/3/1998 70.96 11/4/1998 81.24 11/5/1998 43.95 11/6/1998 30.76 11/7/1998 23.63 11/8/1998 20.82 11/9/1998 38.55 11/10/1998 56.56 11/11/1998 41.83 11/12/1998 30.45 11/13/1998 23.44 11/14/1998 19.23 11/15/1998 16.43 11/16/1998 14.42 11/17/1998 14.21 11/18/1998 14.51 11/19/1998 15.76 11/20/1998 16.69 11/21/1998 15.75 11/22/1998 14.11 11/23/1998 12.54 11/24/1998 11.15 11/25/1998 10.26 11/26/1998 9.40 11/27/1998 9.16 11/28/1998 8.83 11/29/1998 8.38 11/30/1998 7.95 12/1/1998 7.74 12/2/1998 7.46 12/3/1998 7.24 12/4/1998 7.28 12/5/1998 6.95 12/6/1998 6.88 12/7/1998 6.69 12/8/1998 6.50 12/9/1998 6.39 Date Flow 12/10/1998 6.19 12/11/1998 6.07 12/12/1998 5.91 12/13/1998 5.80 12/14/1998 5.73 12/15/1998 5.60 12/16/1998 5.52 12/17/1998 5.44 12/18/1998 5.38 12/19/1998 5.98 12/20/1998 6.17 12/21/1998 6.38 12/22/1998 6.53 12/23/1998 6.62 12/24/1998 6.68 12/25/1998 6.69 12/26/1998 6.58 12/27/1998 6.49 12/28/1998 6.34 12/29/1998 6.16 12/30/1998 5.91 12/31/1998 5.74 1/1/1999 5.61 1/2/1999 5.45 1/3/1999 5.33 1/4/1999 5.22 1/5/1999 5.38 1/6/1999 5.45 1/7/1999 5.44 1/8/1999 5.64 1/9/1999 6.02 1/10/1999 6.15 1/11/1999 6.20 1/12/1999 5.99 1/13/1999 5.83 1/14/1999 5.63 1/15/1999 5.50 1/16/1999 5.34 1/17/1999 5.23 1/18/1999 5.09 1/19/1999 4.98 1/20/1999 4.85 1/21/1999 4.76 1/22/1999 4.83 1/23/1999 5.49 1/24/1999 5.04 Date Flow 1/25/1999 4.97 1/26/1999 4.84 1/27/1999 4.71 1/28/1999 4.57 1/29/1999 5.33 1/30/1999 10.32 1/31/1999 4.31 2/1/1999 4.22 2/2/1999 4.14 2/3/1999 4.06 2/4/1999 4.03 2/5/1999 3.96 2/6/1999 3.92 2/7/1999 3.87 2/8/1999 3.84 2/9/1999 3.77 2/10/1999 3.75 2/11/1999 3.71 2/12/1999 3.68 2/13/1999 3.67 2/14/1999 3.68 2/15/1999 3.67 2/16/1999 3.67 2/17/1999 3.64 2/18/1999 3.59 2/19/1999 3.59 2/20/1999 3.60 2/21/1999 3.69 2/22/1999 3.50 2/23/1999 3.50 2/24/1999 3.50 2/25/1999 3.48 2/26/1999 3.46 2/27/1999 3.43 2/28/1999 3.42 3/1/1999 3.42 3/2/1999 3.41 3/3/1999 3.37 3/4/1999 3.34 3/5/1999 3.31 3/6/1999 3.29 3/7/1999 3.27 3/8/1999 3.27 3/9/1999 3.26 3/10/1999 3.27 3/11/1999 3.26 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 17 Date Flow 3/12/1999 3.22 3/13/1999 3.19 3/14/1999 7.58 3/15/1999 3.57 3/16/1999 4.47 3/17/1999 3.12 3/18/1999 3.15 3/19/1999 3.19 3/20/1999 3.17 3/21/1999 3.12 3/22/1999 3.12 3/23/1999 3.05 3/24/1999 3.12 3/25/1999 3.07 3/26/1999 3.03 3/27/1999 3.00 3/28/1999 2.99 3/29/1999 2.98 3/30/1999 2.97 3/31/1999 2.97 4/1/1999 2.99 4/2/1999 4.53 4/3/1999 2.93 4/4/1999 2.91 4/5/1999 2.94 4/6/1999 3.00 4/7/1999 21.25 4/8/1999 3.35 4/9/1999 2.91 4/10/1999 2.93 4/11/1999 2.93 4/12/1999 2.91 4/13/1999 2.91 4/14/1999 2.91 4/15/1999 2.86 4/16/1999 2.84 4/17/1999 2.92 4/18/1999 3.92 4/19/1999 5.21 4/20/1999 5.25 4/21/1999 4.84 4/22/1999 4.60 4/23/1999 4.13 4/24/1999 4.06 4/25/1999 4.12 4/26/1999 4.17 Date Flow 4/27/1999 4.25 4/28/1999 4.16 4/29/1999 4.13 4/30/1999 4.21 5/1/1999 4.27 5/2/1999 4.21 5/3/1999 4.12 5/4/1999 4.03 5/5/1999 3.94 5/6/1999 3.90 5/7/1999 3.96 5/8/1999 4.07 5/9/1999 4.34 5/10/1999 5.80 5/11/1999 5.97 5/12/1999 6.44 5/13/1999 6.93 5/14/1999 7.75 5/15/1999 9.32 5/16/1999 11.48 5/17/1999 13.61 5/18/1999 15.43 5/19/1999 20.44 5/20/1999 26.10 5/21/1999 30.65 5/22/1999 26.28 5/23/1999 23.57 5/24/1999 21.38 5/25/1999 19.95 5/26/1999 20.57 5/27/1999 20.70 5/28/1999 20.93 5/29/1999 20.70 5/30/1999 25.92 5/31/1999 26.80 6/1/1999 25.71 6/2/1999 24.39 6/3/1999 25.13 6/4/1999 24.65 6/5/1999 26.91 6/6/1999 29.11 6/7/1999 28.24 6/8/1999 31.38 6/9/1999 38.50 6/10/1999 63.65 6/11/1999 85.37 Date Flow 6/12/1999 98.45 6/13/1999 157.22 6/14/1999 169.45 6/15/1999 154.77 6/16/1999 91.31 6/17/1999 53.30 6/18/1999 41.83 6/19/1999 38.27 6/20/1999 39.34 6/21/1999 38.56 6/22/1999 41.07 6/23/1999 40.48 6/24/1999 34.74 6/25/1999 29.65 6/26/1999 25.86 6/27/1999 22.11 6/28/1999 20.49 6/29/1999 20.69 6/30/1999 22.19 7/1/1999 21.89 7/2/1999 21.64 7/3/1999 23.97 7/4/1999 30.89 7/5/1999 32.57 7/6/1999 28.04 7/7/1999 23.54 7/8/1999 20.20 7/9/1999 17.86 7/10/1999 16.81 7/11/1999 16.92 7/12/1999 19.11 7/13/1999 18.75 7/14/1999 16.94 7/15/1999 15.54 7/16/1999 15.12 7/17/1999 14.96 7/18/1999 14.61 7/19/1999 13.91 7/20/1999 13.43 7/21/1999 12.93 7/22/1999 12.71 7/23/1999 12.76 7/24/1999 12.37 7/25/1999 11.66 7/26/1999 11.07 7/27/1999 10.73 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 18 Date Flow 7/28/1999 10.28 7/29/1999 9.92 7/30/1999 9.49 7/31/1999 9.19 8/1/1999 8.85 8/2/1999 8.66 8/3/1999 8.73 8/4/1999 80.81 8/5/1999 139.21 8/6/1999 49.29 8/7/1999 31.31 8/8/1999 23.06 8/9/1999 18.70 8/10/1999 15.77 8/11/1999 13.73 8/12/1999 12.60 8/13/1999 11.64 8/14/1999 10.60 8/15/1999 10.12 8/16/1999 9.62 8/17/1999 9.22 8/18/1999 8.80 8/19/1999 8.42 8/20/1999 8.42 8/21/1999 8.92 8/22/1999 9.70 8/23/1999 9.91 8/24/1999 10.36 8/25/1999 11.40 8/26/1999 11.47 8/27/1999 10.78 8/28/1999 10.12 8/29/1999 9.38 8/30/1999 9.04 8/31/1999 8.64 9/1/1999 8.34 9/2/1999 8.15 9/3/1999 7.93 9/4/1999 7.80 9/5/1999 7.63 9/6/1999 7.50 9/7/1999 7.39 9/8/1999 7.28 9/9/1999 7.12 9/10/1999 12.41 9/11/1999 26.55 Date Flow 9/12/1999 35.41 9/13/1999 24.91 9/14/1999 19.73 9/15/1999 16.31 9/16/1999 14.69 9/17/1999 28.96 9/18/1999 77.37 9/19/1999 59.25 9/20/1999 45.18 9/21/1999 43.01 9/22/1999 51.55 9/23/1999 43.54 9/24/1999 32.65 9/25/1999 24.35 9/26/1999 19.17 9/27/1999 16.04 9/28/1999 14.10 9/29/1999 12.74 9/30/1999 12.14 10/1/1999 13.77 10/2/1999 19.32 10/3/1999 26.75 10/4/1999 43.60 10/5/1999 59.58 10/6/1999 41.60 10/7/1999 34.06 10/8/1999 26.26 10/9/1999 20.30 10/10/1999 16.99 10/11/1999 15.41 10/12/1999 14.85 10/13/1999 14.00 10/14/1999 13.36 10/15/1999 12.97 10/16/1999 12.80 10/17/1999 13.79 10/18/1999 18.96 10/19/1999 20.93 10/20/1999 23.27 10/21/1999 20.11 10/22/1999 16.88 10/23/1999 14.52 10/24/1999 12.61 10/25/1999 11.33 10/26/1999 10.25 10/27/1999 9.56 Date Flow 10/28/1999 9.01 10/29/1999 8.58 10/30/1999 8.18 10/31/1999 7.86 11/1/1999 7.67 11/2/1999 7.35 11/3/1999 7.09 11/4/1999 7.10 11/5/1999 6.76 11/6/1999 6.64 11/7/1999 6.46 11/8/1999 6.32 11/9/1999 6.14 11/10/1999 5.88 11/11/1999 5.78 11/12/1999 6.30 11/13/1999 7.47 11/14/1999 7.85 11/15/1999 7.63 11/16/1999 7.07 11/17/1999 6.77 11/18/1999 6.74 11/19/1999 6.66 11/20/1999 6.44 11/21/1999 6.17 11/22/1999 5.93 11/23/1999 5.69 11/24/1999 5.53 11/25/1999 5.46 11/26/1999 5.43 11/27/1999 5.24 11/28/1999 5.02 11/29/1999 4.94 11/30/1999 4.81 12/1/1999 4.74 12/2/1999 4.62 12/3/1999 4.59 12/4/1999 4.52 12/5/1999 4.42 12/6/1999 4.36 12/7/1999 4.53 12/8/1999 4.53 12/9/1999 4.53 12/10/1999 4.53 12/11/1999 4.50 12/12/1999 5.45 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 19 Date Flow 12/13/1999 4.42 12/14/1999 4.45 12/15/1999 4.52 12/16/1999 5.73 12/17/1999 4.53 12/18/1999 4.60 12/19/1999 4.54 12/20/1999 4.49 12/21/1999 8.46 12/22/1999 19.41 12/23/1999 13.10 12/24/1999 12.91 12/25/1999 13.93 12/26/1999 14.64 12/27/1999 18.77 12/28/1999 13.79 12/29/1999 12.28 12/30/1999 11.31 12/31/1999 10.01 1/1/2000 8.85 1/2/2000 8.16 1/3/2000 7.58 1/4/2000 7.05 1/5/2000 6.69 1/6/2000 6.36 1/7/2000 6.08 1/8/2000 5.79 1/9/2000 5.61 1/10/2000 5.42 1/11/2000 5.26 1/12/2000 5.06 1/13/2000 4.95 1/14/2000 4.82 1/15/2000 4.72 1/16/2000 4.58 1/17/2000 4.53 1/18/2000 4.52 1/19/2000 4.43 1/20/2000 4.33 1/21/2000 4.25 1/22/2000 4.19 1/23/2000 4.13 1/24/2000 4.06 1/25/2000 4.03 1/26/2000 4.34 1/27/2000 4.18 Date Flow 1/28/2000 3.86 1/29/2000 3.83 1/30/2000 4.19 1/31/2000 4.99 2/1/2000 3.78 2/2/2000 3.98 2/3/2000 3.82 2/4/2000 3.76 2/5/2000 3.75 2/6/2000 3.68 2/7/2000 4.08 2/8/2000 4.51 2/9/2000 4.35 2/10/2000 4.39 2/11/2000 4.39 2/12/2000 4.68 2/13/2000 4.57 2/14/2000 4.54 2/15/2000 4.52 2/16/2000 4.45 2/17/2000 4.32 2/18/2000 4.27 2/19/2000 4.20 2/20/2000 4.09 2/21/2000 4.03 2/22/2000 3.94 2/23/2000 3.85 2/24/2000 3.83 2/25/2000 3.75 2/26/2000 3.67 2/27/2000 3.68 2/28/2000 3.67 2/29/2000 3.60 3/1/2000 3.57 3/2/2000 3.61 3/3/2000 3.57 3/4/2000 3.50 3/5/2000 3.55 3/6/2000 3.64 3/7/2000 3.51 3/8/2000 3.48 3/9/2000 3.43 3/10/2000 3.43 3/11/2000 3.87 3/12/2000 3.46 3/13/2000 3.41 Date Flow 3/14/2000 3.40 3/15/2000 25.63 3/16/2000 9.36 3/17/2000 3.36 3/18/2000 3.30 3/19/2000 6.67 3/20/2000 3.28 3/21/2000 3.26 3/22/2000 3.20 3/23/2000 3.19 3/24/2000 3.17 3/25/2000 3.12 3/26/2000 3.82 3/27/2000 7.63 3/28/2000 3.05 3/29/2000 3.05 3/30/2000 3.04 3/31/2000 3.04 4/1/2000 2.97 4/2/2000 5.09 4/3/2000 3.08 4/4/2000 2.98 4/5/2000 2.97 4/6/2000 2.93 4/7/2000 2.92 4/8/2000 2.92 4/9/2000 2.91 4/10/2000 3.04 4/11/2000 3.22 4/12/2000 3.32 4/13/2000 4.24 4/14/2000 4.73 4/15/2000 5.12 4/16/2000 5.19 4/17/2000 4.90 4/18/2000 4.60 4/19/2000 4.54 4/20/2000 4.62 4/21/2000 4.95 4/22/2000 4.97 4/23/2000 4.97 4/24/2000 4.95 4/25/2000 4.97 4/26/2000 5.03 4/27/2000 5.25 4/28/2000 5.41 POLARCONSULT ALASKA, INC. MOUNTAIN CREEK HYDROLOGY REPORT OLD HARBOR, AK MAY 4, 2010 PAGE 20 Date Flow 4/29/2000 5.69 4/30/2000 6.05 5/1/2000 6.66 5/2/2000 7.70 5/3/2000 8.32 5/4/2000 9.20 5/5/2000 9.95 5/6/2000 10.39 5/7/2000 12.14 5/8/2000 13.63 5/9/2000 13.13 5/10/2000 13.19 5/11/2000 13.23 5/12/2000 13.30 5/13/2000 14.45 5/14/2000 14.72 5/15/2000 15.49 5/16/2000 16.51 5/17/2000 16.51 5/18/2000 17.22 5/19/2000 17.02 5/20/2000 15.69 5/21/2000 14.81 5/22/2000 14.33 5/23/2000 13.75 5/24/2000 13.17 5/25/2000 13.08 5/26/2000 13.50 5/27/2000 14.50 5/28/2000 16.95 5/29/2000 20.11 5/30/2000 23.66 5/31/2000 23.76 6/1/2000 22.58 6/2/2000 20.61 6/3/2000 19.96 6/4/2000 20.54 6/5/2000 21.67 6/6/2000 23.39 6/7/2000 37.69 6/8/2000 67.61 6/9/2000 53.78 6/10/2000 42.51 6/11/2000 44.58 6/12/2000 135.24 6/13/2000 109.42 Date Flow 6/14/2000 86.20 6/15/2000 64.74 6/16/2000 51.62 6/17/2000 43.12 6/18/2000 36.81 6/19/2000 46.96 6/20/2000 69.32 6/21/2000 47.65 6/22/2000 37.08 6/23/2000 34.71 6/24/2000 123.50 6/25/2000 98.56 6/26/2000 61.96 6/27/2000 64.83 6/28/2000 49.90 6/29/2000 58.18 6/30/2000 68.50 7/1/2000 50.32 7/2/2000 42.81 7/3/2000 41.28 7/4/2000 37.83 7/5/2000 34.80 7/6/2000 35.89 7/7/2000 37.49 7/8/2000 35.83 7/9/2000 32.90 7/10/2000 28.58 7/11/2000 28.31 7/12/2000 35.18 7/13/2000 40.20 7/14/2000 37.48 7/15/2000 30.71 7/16/2000 26.57 7/17/2000 24.03 7/18/2000 22.15 7/19/2000 19.84 7/20/2000 17.89 7/21/2000 16.39 7/22/2000 15.61 7/23/2000 15.02 7/24/2000 15.12 7/25/2000 15.33 7/26/2000 14.92 7/27/2000 14.35 7/28/2000 14.14 7/29/2000 14.21 Date Flow 7/30/2000 13.93 7/31/2000 13.52 8/1/2000 12.87 8/2/2000 48.64 8/3/2000 65.59 8/4/2000 38.49 8/5/2000 28.33 8/6/2000 22.22 8/7/2000 18.55 8/8/2000 16.26 8/9/2000 14.54 8/10/2000 13.52 8/11/2000 12.93 8/12/2000 12.25 8/13/2000 11.62 8/14/2000 11.00 8/15/2000 10.51 8/16/2000 10.06