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HomeMy WebLinkAboutAPA2974')\< 1~'Zs­ ,':/6 p\2? ~-,J.'2.4:t"l SOUTHCENTRAL RAILBELT AREA ALASI(li--_....,.... , .UPPER SUSITNA RIVER BASIN ·.INTERIM FEASIBIliTY·REPORr .APfP>EINJD~11· ,!PART :2 SECTION GI SECTION H. SECTION II MARKETABILITY ANALYSES TRANSMISSION SYSTEM ENVIRONMENTAL ASSESSMENT FOR TRANSMISSION SYSTEMS 1/.>.~ / /l ; ARLIS ( Alask3 Resources Library [i.J InfofmatlOll Ser.-vi_ce_s.....--....... Anchorage,Aiask ~.CORPS OF £10- .~G"l HYDROELECTRIC POWER .a II :\1 §I !!!I J II :i I~I ~' AN"D RELATED P1[[RJPOSES,5\i 00 .-~. tfll'NiAL'177 5 ~ SECTION G MARKETABILITY ANALYSES UNITED STATES DEPARTMENT OF THE INTERIOR Alaska Power Administration Upper Susitna River Hydroelectric Studies Report on Markets for Project Power December 1975 Contents Title Part I -INTRODUCTION . . . . . . . . . . . . . . Purpose and Scope . Alternative Plans for Upper Susitna Hydroelectic Development Previous Studies . Part II -SUMMARY Part III -POWER MARKET AREAS Anchorage -Cook Inlet Area Fairbanks -Tanana Valley Area Valdez -Glennallen Area.. . . Part IV -EXISTING POWER SYSTEMS Utility Systems and Service Areas National Defense Power Systems Industrial Power Systems Existing and Planned Generation Part V -POWER REQUIREMENTS Power Requirements Data Annual Requirements Load Distribution Data. Studies for Alaska Power Survey Factors Influencing Power Demands Population Change . . . . . . Economic Growth . Changes in Use of Electric Energy 1975 Estimates of Future Power Requirements Copper Valley Power Requirements Existing Situations . Future Utility Loads . . . . . Industrial Loads . . . . . . . Criteria for Capacity and Energy Distribution Energy Distribution Capacity Requirements . . . . . . . . . i Page No. G-l G-l G-l G-S G-7 G-7 G-8 G-9 G-IO G-IO G-12 G-13 G-13 G-17 G-17 G-17 G-23 G-30 G-36 G-36 G-37 G-39 G-41 G-52 G-52 G-52 G-53 G-54 G-54 G-56 Part VI -ALTERNATIVE POWER SOURCES Power Survey Studies . . . . . . . Energy and Power Cost Trends . . . Review of Fuel Costs and Availability . Review of Available Alternatives Coal-fired Steamplants Hydro . Nuclear . Other Alternatives Part VII -FINANCIAL ANALYSES Market for Project Power . . . Scoping Analysis . . . . . . Comparison with May 1974 Status Report Revised Cost Estimates . . . . . . . . . Average Rate Determination for Proposed Plan Power Marketing Considerations Market Aspects of Other Transmission Alterna ti ves . . . . . . . . . . . . . . . . Anchorage-Cook Inlet Area . . . . . . . . . . . Glennallen and Other Points on the Richardson Highway . Exhibit ]:Partial Bibliography of Related Studies Exhibit 2:Report on Operation,Maintenance,and Replacements i i G-59 G-59 G-62 G-63 G-65 G-65 G-72 G-72 G-73 G-74 G-74 G-77 G-85 G-87 G-87 G-89 G-90 G-90 G-90 List of Tables Page No. I.Alternative System Plans --Installed Capacity and Firm Energy .G-3 2.Summary of Existing Generating Capacity G-14 3.Anchorage and Fairbanks Area Load data,1964-1974 G-18 4.Utility Sales and Customers -Railbelt Area,1965-1973 G-21 5.Energy Use per Customer,J.965-1973 G-22 6.Monthly Peak Loads,1971 to 1974 G-25 7.Monthly Load Factors,1972 and 1973 G-29 8.Utility System Requirements,1960-1972 G-32 9.Regional Utility Load Estimates,1972-2000, (Alaska Power Survey).G-34 10.Regional Total Load Estimates,1972-2000, (Alaska Power Survey)G-35 II.Estimated Utility,National Defense,and Industrial Power Requirements,1974-2000 .G-42 12.Assumed Industrial Development G-49 13.Estimated Industrial Power Requirements G-51 14.Monthly Energy Requirements as Percent of Annual Requirements .G-55 15.Future Generation Cost Estimates (Alaska Power Survey)G-60 16.Alternative Generation Costs for Conventional Coal-fired Steamplants G-f,7 17.Assumed Market for Upper Susitna Power G-76 18.Average Rates for Repayment for Alternative Development Plans..G-78 19.Cost Summaries for Alternative Systems G-79 20.Comparison with May 1974 Status Report G-86 21.Average Rate Determination -System #5 G-88 List of Figures 1.Location Map -Upper Susitna Project and Railbelt Power Markets G-2 2.Areas Presently Served by Railbelt Utilities G-ll 3.Monthly Peak Loads,1963 to 1974 G-24 4.System Daily Generation Curves G-26 5.Alaska Planning Regions . . . .G-31 6.Estimated Utility,National Defense,and Industrial Power Requirements,1974 to 2000 G-45 ; i i Part I INTRODUCTION Purpose and Scope This study will analyze the power market of an Upper Susitna hydroelectric development.Two major areas of concern will be investigated.These are: 1.Project design in relation to the use of the project power;and 2.Financial feasibility under existing repayment criteria. Study elements include: 1.estimates of future power requirements a.timing b .magnitude c.load characteristics 2.estimates of future power sales and rates required for repayment 3.analysis of costs of alternative sources of power The level of detail is that required for demonstration of project feasibility for purposes of consideration by the Congress for project authorization. Alternative Plans for Upper Susitna Hydroelectric Development Figure 1 shows general locations of the potential units of the Upper Susitna Project in relationship to the Alaska Railbelt.The four key Upper Susitna damsites are Devil Canyon,Watana,Vee,and Denali. Several alternative systems for developing the Upper Susitna Project were evaluated.Table 1 summarizes data on energy and power capability for these alternative systems. The Corps of Engineers proposes an initial development including the Devil Canyon and Watana sites.(System #5) System #1 (Devil Canyon and Denali)is analogous to the intitial development plan advanced in earlier studies by the Bureau of Reclamation and APA. System #4 is the four-dam ultimate development plan identified in previous USBR-APA studies. Appendix I G-l U.S.DEPARTMENT OF THE INTERIOR A LA SKA POWE R ADM IN I STRAT ION UPPER SUSITNA BASIN LOCATION MAP ! / ") I ) Appendix I FIGUREG-l G-2 SCALE ~-----o 50 2 IOOMile5 APA 2-74 _.. - Table1.AlternativeSystemPlansInstalledCapacity&FirmEnergyW.S.el.P.O.L.DevilSystem.M.S.L.DateCanyonWatanaVeeSystemTotalInstalledFirmInstalledFirmInstalledFirmInstalledFirmSecondaryCapacityEnergyCapacityEnergyCapacityEnergyCapacityEnergyEnergy1000Million1000Million1000Million1000MillionMillionkwkwhkwkwhkwkwhkwkwhkwhSystem#1DevilCanyon145019855802497Denali253519905802497701System#2DevilCanyon14501985--6002628Watana20501990470205910704687946System#3DevilCanyon145019857003066Watana205019906702935Denali2535199513706001350System#4DevilCanyon145019857133119Denali25351990Vee230019953001314.Watana19052000421184014346273640System#5.Watana220019867923101DevilCanyon145019907763048G)---j:t>15686149701I:t>-ow0::1-01mrT1::lNo~:s:System#5istheproposedinitialdevelopmentplan.Cl..G)-'.IXDataisfromCorpsofEngineersstudies.-.l....... Previous Studies There is a fairly substantial backlog of power system and project studies relevant to the current evaluation of the Upper Susitna River Project. A partial bibliography is appended.The previous studies most relevant to power market considerations include: 1.Advisory Committee studies completed in 1974 for the Federal Power Commission's (FPC)new Alaska Power Survey.The studies include evaluation of existing power systems and future ,needs through the year 2000,and the main generation and transmission alternatives available to meet the needs.The power requirement studies and alternative generation system studies for the new power survey were used extensively in the current study.The FPC summary report for its new survey is not yet available. 2.A series of utility system studies for Railbelt area utilities include assessments of loads,power costs,and generation and transmission alternatives. 3.Previous work by the Alaska Power Administration,the Bureau of Reclamation,the utility systems,and industry on studies 'of various plans for Railbelt transmission interconnections and the Upper Susitna hydroelectric potential.The most recent of these are the May 1974! Status Report ~,the Devil Canyon Project by APA and the September 1974, Reassessment Report on Upper 'Susitna River Hydroelectric Development prepared for the State of Alaska by the Henry J.Kaiser Company. It should be noted that many of the studies listed in the bibliography represent a period in history when there was very little concern about energy conserva- tion,growth,and needs for conserving oil and natural gas resources. Similarly,many of these studies reflected anticipation of long term,very low cost energy supplies.In this regard,the studies for the new power survey are considered particularly significant in that they provide a first assessment of Alaska power system needs reflecting the current concerns for energy and fuels conservation and the environment,and the rapidly increasing costs of energy ih the economy. Appendix I G-4 Part II SUMMARY 1.Studies of future power requirements prepared for the FPC Alaska Power Survey were reviewed in light of new data for the years 1973 and 1974.New estimates of power requirements through the year 2000 were prepared reflecting the best current estimates of loads that would actually be served from an interconnected Railbelt power system serving the Fairbanks-Tanana Valley area and the Anchorage- Cook Inlet area.These new estimates are summarized on Table 11. 2.Additional data was compiled for potential loads in the Copper Valley area,and a preliminary analysis of electric service from the Upper Susitna Project to this area was made.It does not appear feasible to include service to this area during initial stages of the project. 3.Available data on area load characteristics were examined in light of future system operation;estimates of monthly energy distri- bution were prepared for sizing project reservoirs;and an annual plant factor of 50 percent was selected for sizing project power plants. 4.Studies of alternative power sources prepared for the FPC Alaska Power Survey were reviewed in light of recent studies and trends in energy.It was concluded that oil and natural gas fired generation is not a desirable alternative for major new power supplies in the Alaska Railbelt in 1985 and later years.It is considered that coal-fired steanlplants would be the most likely alternative in lieu of Susitna hydro.The power survey steamplant cost estimates were updated for comparison purposes. 5.A set of preliminary rate studies was made for use in the scoping analysis of alternative Susitna hydro development plans.These studies are premised on September 1975 plans and cost estimates do not reflect latest estimates for the final project report.The studies indicated an average rate of 19.7 mills per kilowatt hour for the Corps proposed plan of development (System #5)and average rates ranging from 20.9 to 24.5 mills for the alternative systems. The studies also indicated that alternative staging assumptions utilizing the same designs and cost estimates would narrow the range to 20.9 to 22.8 mills per kilowatthour,a difference of less than ten percent. These rates are substantially higher than present natural gas-fired generation in the Cook Inlet area,but significantly lower than current estimates for new coal-fired plants. Appendix I G-5 6.The above values were reviewed in light of the final plans and cost estimates,with the indication that the proposed plan (System #5) would have approxin'.ately a 10 percent advantage over the alternative hydro systems from the viewpoint of cost of power to the consumer. 7.APP.estin:.ates that an average rate for firm energy of 21.1 mills per kilowatthour would be required to repay costs of the project under current Federal repayment criteria.This is premised on cost estimates using January 1975 price levels a.nd includes amorti7.ation of the investment and annual costs for operation,maintenance,and replacements.The compilations for the average firm energy rate appear on Table 21. 8.The studies reflect very rapidly changing values in energy and costs of doing business.It is estirrated that increase iI')costs and Federal interest rate for repayment amount to over a 40 percent increase in rates for repayment as compared with conditions reported in AP A IsMay 1974 status report on Devil Canyon.If the pres en t costs are escalated at 5 percent per year,average rates for Upper Susitna power would likely exceed 40 mills per kilowatthour when the project is actually brought on line. 9.The changing costs for hydro development must be considered in light of the rapid changes in costs for other power producing facilities and fuels.It appears reasonable to assume that future cost escalation for hydro construction will be at a slower rate than for average energy costs in the economy.After completion, any increases in costs for the hydro power would likely be very small. 10.With the prevailing intersts rates,power rates are very sensitive to any stretch-out of construction period and the si2'e of invest- ment accumulated prior to start of revenues.Careful attention to staging opportunities will be needed in final design of the project. 11.,1..2 A also prepared estimates of annual costs for operation,mainte- nance,power markets,and interim replacements for use in the project economic and financial analysis.This date is summarized in Exhibit 2 of this report. Appendix G-6 Part III POWER MARKET AREAS Throughout its history of investigations,the Upper Susitna River Project has been of interest for its central location to the Fairbanks and Anchorage areas which have Alaska 1 s largest concentrations of population,economic activity,services,and industry.Under any plan of development,major portions of the project power would be utilized in these two areas.Additionally, the basic project transmission system servicing Anchorage and Fairbanks could provide electric service to present and future developments between the two points.Electrification of the Alaska Railroad is another possibility. These major market areas are referred to as the Anchorage-Cook Inlet area and the Fairbanks-Tanana Valley area. Additional potential markets are utility and industrial loads along the pipeline corridor between Delta Junction and Valdez. Anchorage-Cook Inlet Area Generally,this has reference to the developed areas around Upper Cook Inlet including the Anchorage area,the Kenai Peninsula,and the Matanuska and Susitna valleys.This includes most of the population and economic activity in the Matanuska-Susitna,Greater Anchorage Area,and Kenai Peninsula Boroughs. This general area has been the focal point for most of the State's growth in terms of population,business,services,and industry since World War II. Major building of defense installations,expansion of government services, discovery and development of natural gas and oil in the Cook Inlet area, and emergence of Anchorage as the State's center of government,finance, travel,and tourism are major elements in the history of this area. Because of its central role in business,commerce,and government,the Anchorage area is directly influenced by economic activity elsewhere in the State.Much of the buildup in anticipation of the Alyeska pipeline, much of growth related to Cook Inlet oil development,and much of the growth in State and local government services since Statehood have occurred in the immediate Anchorage vicinity.The Greater Anchorage Area Borough estimated its July 1,1974,population at 162,500,or an increase of nearly 30%since the 1970 census.This is over 45 percent of total estimated State population in 1974. Appendix I G-7 The Matanuska-Susitna Borough includes several small cities (Palmer, Wasilla,Talkeetna)and the state's largest agricultural community.Other economic activities include a recreation industry and some light manufacturing. Much recent growth in the Borough has been in residential and recreation homes for workers in the Anchorage area.Estimated 1974 population was 9,787. The Kenai Peninsula Borough includes the cities of Kenai,Soldatna,Homer, Seldovia,and Seward with important fisheries,oil and gas,and recreation industries.Estimated 1974 population was 13,962. Both the Matanuska-Susitna and Kenai Peninsula Boroughs will have some urban expansion over the next few decades.Pressures for urban development would be substantially increased if the proposed surface crossings of the Knik and Turnagain Arms were constructed. Present and proposed activities indicate likelihood of rapid growth in this general Cook Inlet area for the foreseeable future.Much of this activity is related to oil and natural gas including expansion of the refineries at Kenai,proposals for major LNG exports to the south"48"and probable additional offshore oil and gas development.The State's Capital Site Selection Committee has narrowed their search to four sites for the new capital city, of which three locations are in the Susitna Valley.The area will continue to serve as the transportation hub of westward Alaska,and tourism demands will likely continue to increase rapidly.Major local development seems probable. Fairbanks-Tanana Valley Area Fairbanks is Alaska's second largest city,the trade center for much of Alaska's Interior,service center for two major military bases,and site of the U ni versity of Alaska and its associated research center.Several outlying communities including Nenana,Clear,North Pole,and Delta Junction are loosely included in the "Fairbanks-Tanana Valley"area.Historically, the area is famous for its gold.Currently,it is in a major boom connected with the construction of Alyeska pipeline. The Fairbanks-North Star Borough had an estimated 1974 population of 50,762 and the outlying communities within the power market area probably totaled about 10,000 population at that time. Appendix I G-8 - ,..-It is generally felt that post-pipeline growth in the Fairbanks area will be at a slower pace than the Anchorage-Cook Inlet area.However,major future resource developments in the Interior and the North Slope would have direct impact on the Fairbanks economy. Valdez-Glennallen Like Fairbanks,the two communities are heavily impacted by pipeline construction,especially Valdez because of the concentration of work on the pipeline terminal.Longer range prospects probably include a more stable economy associated with the pipeline and terminal operations and the immensely valuable recreation resources of this area. Appendix I G-9 Part IV EXISTING POWER SYSTEMS Utility Systems and Service Areas - The electric utilities in the power market area are listed below and areas presently receiving electric service are indicated on Figure 2. An chorage Area - Anchorage Municipal Light and Power (AML&P) Chugach Electric Association (CEA) Matanuska Electric Association (MEA) Homer Electric Association (HEA) Seward Electric System (SES) Fairbanks Area - Fairbanks Iv1unicipal Utility System (FMUS) Golden Valley Electric Association (GVEA) Valdez and Glennallen Area - Copper Valley Electric Association (CVEA) Alaska Power Administration operates the Eklutna Hydroelectric Project and markets wholesale power to CEA,AML&P,and MEA. AML&P serves the Anchorage Municipal area.CEA supplies power to the Anchorage suburban and surrounding rural areas and provides power at wholesale rates to HEA,SES,and MEA.The HEA service area covers the western portion of the Kenai Peninsula including Seldovia,across the bay from Homer.r-.fEA serves the town of Palmer,the surrounding rural area in the Matanuska and Susitna Valleys. The utilities serving the Anchorage-Cook Inlet area are presently loosely interconnected through facilities of APA and CEA.An emergency tie is available between the AML&P and Anchorage area military installations. For this study it is assumed that Upper Susitna power would be delivered at a new substation on the CEA system in the vicinity of Point HacKenzie on the north side of Knik Arm,and that project power would be wheeled over the CEA system to other utilities in the general Cook Inlet area. Appendix I G-10 '00 MiI.s ---2 Appendix I FIGURE G-2 G-ll --_./ SCALE ~-----......--.-o 50 U.S.DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION UPPER SUSITNA RIVER PROJECT AREAS PRESENTLY SERVED BY RAILBELT UTILITIES ,,-.. FMlfS serves the Fairbanks municipal area,while GVEA provides service to the rural areas.The Fairbanks area power suppliers have the most complete power pooling agreement in the State.FMUS,GVEA, the University of Alaska and the military bases have an arrangement which includes provisions for sharing reserves and energy interchange In addition,GVEA operates the Fort Wainwright steamplant under an agreement with the army. The delivery point for Upper Susitna power to the GVEA and FMUS systems is assumed at the existing Gold Hill substation of GVEA near Fairbanks. The Copper Valley Electric Association serves both Glennallen and Valdez.Radial distribution lines of CVEA extend from Glennallen 30 miles north on the Copper River,55 miles south on the Copper River to Lower Tonsina and 70 miles west on Glenn Highway.For this study, it is assuwed that project power would be delivered to the CVEA system at Glenallen. National Defense Power Systems The six major national defense installations in the power market area are: (there are numerous smaller installations) Anchorage area - Elmendorf Air Force Base Fort Richardson Fairbanks area - Clear Air Force Base Eielson Air Force Base Fort Greeley Fort Wainwright Each of the major bases has its own steamplant used for power and for central space heating source.Except for Clear Air Force Base,each is interconnected to provide power to or receive power from the local utilities. In the past,national defense electric generation has been a major portion of the total installed capacity.With the projected stability of military sites and the growth of the utilities,the national defense installation will become a less significant part of the total generation capacity. Appendix I G-12 - Industrial Power Systems Three industrial plants on the Kenai Peninsula maintain their own powerplants,but are interconnected with the HEA system.Colliers chemical plant generates its basic power and energy needs receiving only standby capacity from HEA.Kenai Liquified Natural Gas plant buys energy from HEA,but has its own standby .generation.Tesoro Refinery does both;buys from HEA and furnishes part of its own needs. Other self-supplied industrial generators include oil platform and pipeline terminal facilities in the Cook Inlet area.The Valdez pipeline terminal will have a sizable powerplant,and most of the pumping stations on the Alyeska pipeline will have small powerplants. Existing and Planned Generation Table 2 provides a summary of existing generating capacity.The table was generally current as of mid-1974.The Anchorage-Cook Inlet area had a total installed capacity of 414.8 MW in 1974.Natural gas fired turbines were the predominant energy source with 341.7 MW of installed capacity.Hydroelectric capacity of 45 MW was available from two projects,Eklutna and Cooper Lake.Steam turbines comprised 14.5 MW of capacity and diesel generation,mostly in standby service accounted for the remaining 13.5 MW. The Fairbanks-Tanana Valley area utilities had a total installed capacity of 127.7 MW in 1974.Steam turbines provided the largest block of power in the area with an installed capacity of 53.5 MW.Gas turbine generation Coil-fired)provided 42.1 MW of power and diesel generators contributed 32.1 MW to the area. Appendix I G-13 Table 2.Summary of Existing Generating Capacity -, Installed Capacity -1000 kw Diesel Gas Steam Hydro IC Turbine Turbine Total Anchorage-Cook Inlet Area: Utility System 45.0 13.5 341.7 14.5 414.8 National Defense 9.3 49.5 58.8 Industrial System 10.1 2.3 12.4 Subtotal 45.0 32.9 344.0 64.0 486.0 Fairbanks-Tanana Valley Area: Utility System 32.1 42.I 53.5 127.7 National Defense 14.9 63.0 77 .9 Subtotal Valdez and Glennallen 47.0 6.2 42.1 116.5 205.6 6.2 Notes:The majority of the diesel generation is in standby status except at Valdez and Glennallen. Source:1974 Alaska Power Survey,Technical Advisory Report,Resources and Electric Power Generation,Appendix A and Alaska Electric Power Statistics,1960-1973,APA. Appendix I TABLE G-2 G-14 - Generation facili ties will need to be ins taIled to meet requirements between 1975 and 1985 when the first Susitna River hydro unit could be on the line.Current plans of the utilities include the following units: Planned Capaci ty,MW Utilities Anchorage Area: 1975 1976 1977 Chugach Electric Association (CEA) Unit 4 10 Units 5 & 6 53 53 Anchorage Municipal Light &Power (AML&P) Units 8 & 9 Unit 10 Fairbanks Area: Golden Valley Electric Association (GVEA) North Pole 15 78 15 40 53 161 53 53 -- Source:Environmental impact statements.public meetings and APA personal contacts. The AML&P 15 MW units are steam turbine heat recovery units. The remainder of the units are gas turbines.The 53 MW ratings are baseload ratings.Winter peak load ratings are 70 MW.The Anchorage area units are natural gas fired,while the Fairbanks units are oil fired. Estimates of future power requirements indicate substantial additional capacity needs by 1985 over and above the present plans.Studies of other generation,mainly coal fired steamplants,have been made by the utilities but commitments to longer range generation with coal have not been made. Append;x I . G-15 Natural gas supply contracts have been secured by Chugach Electric Association through 1998 in the Beluga area.The natural gas available under present contracts could meet the expected 1982 CEA generation needs of approximately 536 !\'fW.1/ CVEA recently installed 1,000 kw and 2,624 kw diesel generators at Valdez and ordered two 2,624 kw diesel electric generators for Glennallen.Studies are undenvay on a 6,000 kw Solomon Gulch hydrc project near Valdez. In addition to the utility plans,some new self-supplif'd industrial plants art'planned or under construction.These include power supplies for the Alyeska pipeline terminal (oil-fired steam)and for pumping stations (small diesel plants).Electric service requirements for the pumping stations in the immediate vicinity of Glennallen and Fairbanks are to be supplied by CVEA and GVEA,respectively. There also may be new industrial powerplants in connection with refinery e>.-pansion and the proposed new LNG plants on the Kenai Peninsula. Generally,industry has shown a willingness to purchase power from the utilities if adequate reliable supplies can be guaranteed. 1/CEA Environmental Analysis of Proposed 230 kv Transmission Line from Teeland substation to Reed substation,page 8. Appendix I G-16 - - Part V.POWER REQUIREMENTS Power requirement studies for this report included:a review of the regional power requirement studies for the new FPC Alaska Power Survey and other recent load estimates;analyses of recent trends in power consumption;and preparation of a new set of load estimates reflecting the present best estimates of future area requirements through the year 2000. The studies also included analysis of load characteristics as needed to develop criteria for installed capacity and reservoir regulation for power production from the proposed hydroelectric development. Power Requirements Data This section summarizes data used in estimating future power requirements and determining criteria for energy distribution and peaking capacity for the Susitna hydroelectric development.The estimates of future requirements are premised on assumed data and annual future growth trends.Energy distribution and peaking capacity criteria are estimated from load distribution data. Annual Requirements Table 3 summarizes annual power requirement data for the Anchorage- Cook Inlet and Fairbanks-Tanana Valley areas for the years 1964 to 1974.The table includes:utility system annual energy requirements, annual peak load,annual load factor,and rates of increase in energy requirements;similar data for representative years for the national defense installations in the two areas;and 1972 requirements for the self-supplied industrial plants on the Kenai Peninsula. Table 3 also includes a summation of these loads for the years 1964, 1972,and 1974 (assuming industrial loads in 1972 and 1974 are equal). The total area electrical energy requirements increased by a factor of 2.63 during the 1964-1974 period,for an average increase of just nine percent per year.The utility requirements increased at an average rate of 14.2 percent per year and exceeded 12 percent growth in all but two years of that period.Average growth was 14.5 percent and 13.2 percent for Anchorage and Fairbanks,respectively. Appendix I G-17 Table 3.Anchorage and Fairbanks Area Load Data,1964 -1974 - Energy Peak Load 1 f illion Load Factor Annual Increase Year Kwh 1v1W Percent Million-kwh % Utility Requiremen ts -Anchorage Area 1964 338.2 83.6 46.1 1965 401.0 91.9 49.8 62.8 18.6 1966 450.3 103.0 49.9 49.8 12.3 1967 497.1 112.1 50.6 46.8 10.4 1968 563.6 129.9 49.4 66.5 13.4 1969 630.5 139.6 51.6 66.9 11.9 1970 741.2 165.3 51.2 110.7 17.6 1971 887.1 189.3 53.5 145.9 19.7 1972 984.3 223.9 50.2 97.2 11.0 1973 1134.2 252.0 51.4 149.9 15.2 1974 1305.3 284.0 52.5 171.1 15.1 Utility Requirements -Fairbanks Area 1964 95.7 23.6 46.2 1965 103.7 26.5 44.7 8.0 8.4 1966 115.9 27.8 47.6 12.2 11.8 1967 128,6 31.8 46.2 12.7 11.0 1968 158.2 42.7 42.2 29.6 23.0 1969 186.0 45.6 46.6 27.8 17 .6 1970 231.0 57.0 46.3 45.0 24.2 1971 267.3 71.2 43.1 36.3 15.7 1972 305.5 71.9 48.4 38.2 14.3 1973 315.0 71.5 50.2 9.5 3.1 1974 330.0 82.9 45.4 15.0 4.8 Utility Requirements -Anchorage &Fairbanks Area 1964 433.9 107.2 64.1 1965 504.7 118.4 48.7 70.8 16.3 1966 566.2 130.8 49.4 61.5 12.2 1967 625.7 143.9 49.6 59.5 10.5 1968 721.8 172 .6 47.6 96.1 15.4 1969 816.5 185.2 50.3 94.7 13.1 1970 972.2 272.3 49.9 155.7 19 .1 1971 1156.4 260.5 50.7 184.2 18.9 1972 1289.8 295.8 49.6 133.4 11.5 1973 1449.2 323.5 51.1 159.4 12.4 1974 1635.3 366.9 50.9 186.1 12.8 - Appendix I TABLE G-3 G-18 Table 3.Anchorage and Fairbanks Area Load Data,1964 -1974 (corit.) Net Peak Load Million Load Factor Year Kwh MW .Percent Self-Supplied Industry -Kenai Peninsula 1972 54.3 9.7 53.2 National Defense -Anchorage 1964 141 32 50.2 1972 166.5 33.9 55.9 1974 155.1 32.6 '54.3 National Defense -Fairbanks 1964 197 37 60.6 1972 203.3 41.4 55.9 1974 197 .0 40.8 55.1 Total Requirements -Utility,Industrial and National Defense 1964 772 176 50.1 1972 1,705 381 51.0 1974 1/2,033 450 51.6 1/Assumes Industrial loads in 1974 same as 1972. Notes:II Anchorage ll utility data reflects requirements of CEA,AML&P, MEA,HEA,and SES. IIFairbanks li utility date reflects sum of GVEA and FMUS. Appendix I G-19 The data in Table 3 indicates that National Defense requirements have been quite stable over the period.National Defense requirements totaled 44 percent of total area requirements in 1964,but only 17 percent in 1974. With the exception of the self-supplied industry in the Kenai Peninsula, area industrial loads are supplied by the utilities and included in the utility statistics. Tables 4 and 5 illustrate the major components of growth in the utility requirements increase in customers and increase in use per customer. Number of customers is generally analogous to increase in area population and economic activities.Use per customer will reflect a variety of factors such as additional appliances,a general trend towards better housing and expanding business in the new suburban areas. Table 5 shows energy use per customer and annual increased use for the period 1965 through 1973.The main observation is that the use per customer has increased significantly,and is still increasing.The Anchorage area customer averaged 5.2 percent annual increase while the Fairbanks area averaged 9.8 percent annual increase.The combined weighted annual growth was 6.2 percent. Estimates of future power requirements presented subsequently assume this large rate of growth will not continue indefinitely,and that saturation of home appliances and conservation efforts will stabilize the per customer use. The peak load data on Table 3 represents the sum of annual peaks from the various systems.Area total peak load would be somewhat smaller in most cases due to diversity. The data shown on Table 3 indicated that both area load centers have a fluctuating annual utility load factor very close to 50 percent.The industry on the Kenai Peninsula has been slightly higher at 53 percent. National Defense has the highest at 55 percent.Area total load factor would be somewhat higher due to diversity. The data in Table 3 indicates that for 1974,approximately 74 percent of the total system energy is used in the Anchorage area and 26 percent in the Fairbanks area.Comparable figures for the utility portion was 80 percent in the Anchorage area and 20 percent in the Fairbanks area. Appendix I G-20 - - \\JJTable4.Utility-SalesandCustomers-RallbeltArea,1965-1973ResidentialCommercial/IndustrialTotal1965197019731965ill.Q..!lli.1965.!2lQ..!ill.AnchorageArea(e)(e)(e)AHl&P1000KWH34,65654.51884.000( )92.889159,538231•OOO( )133.083222,200325.200(e)Customers6,6648,86011,400e2,0712,2212,540e8.74211.23314.100CEA1000KWH111.587 198.856287.87949.74799.387174,187 164.507-309.049483.029Customers15.44923.35829.0771.0281,7912.46516.55925.26331.665MEA1000KWH17.11529.70252.30516.70819.68129.50133.95249.56482.018Customers2.6383.6645,0294115467303.0504.2135.765HEA1000KWH6.17619.29031.84816.74953.84573,94323.85575.000108.407Customers1.4132.7073.8913585428301.8323.3294.822TOTAL1000KWH169.534302.366456.032176.093332.451508,631355,397655.813998.65"Customers26.16438.58949,3973.8685.1006.56530.18344.03856.352FairbanksArea._-FMU1000KWH16.17223.61927.300(e)41.500(e)43.96271.408(e)22.10937.94183.000( )Customers4.1474.4434.500(e)7958749004.9985.4925.600eGVEA1000KWH23,14267.123106.8822).85069.06498.74449.357136.486206.108Customers3.9085.8467,3825238179734.478.6,6718.363TOTAL1000KWH39.31490.742134.18247.959107.005140.24493.319207.894289.108Customers8.05510,28911.8821.318I,6911.8739.47612.16313.963Rai1beItArea~.Q-!:PTOTAL1000KWH208,848393.108590.214224.052439.456648.875448.716863.707'.287.762I;:P"OCustomers34.21948.87861.2795.1866.7918.43839.65956.20170.315NOJ"O-'r(1)-fTl::3Cl..Q-I.I'x(e)Estimated+::>I-l Source:REAandAPAdata.}) Load Distribution Data Figure 3 shows monthly peak utility loads,1963 to 1974,for the Anchoragt'- Cook Inlet and Fairbanks-Tanana Valley areas.Table 6 summarizes monthly peak data for the 1971 to 1974 period.The prominent aspect is that summer peaks are running about 60 percent of annual peak.This indicates that summer peaking requirements will not be very influential in determining capacity requirements.Winter peaks shown in the table probably reflect a combination of growth and climate differences.It is of interest that the 1973-]974 peaks in November,December,January,and February were of about the same magnitude,while January peaks the preceding two winters were very prominent. Figure 4 shows representative weekly load curves for Anchorage area utilities.Summer and winter load shapes appear similar except that the winter show a more pronounced evening peak.The daily peaks in both summer and winter tend to be broad. Data on Figure 4 indicates the minimum hourly load during summer ranging from 29 to 31 percent of the winter peak. Table 7 shows representative monthly load factors.These are uniformly high throughout the year,in the range of 70 to 76 percent.It is anticipated that similar data on a weekly basis would show weekly load factors are frequently above 80 percent. Appendix I G-23 r---~---~--~-~-~-~-~-------------------~-----------,- N.... 0> o.... 0> .... 0> oo N o of" I n.~« :>;W !~ , U <tl -'-.'" %L9~ %00<; o Q o 0:!N %8<;L Ul..oz I %Lt>6 ii: Il3 ...J <i.~ii: ~-I.i Il3 -:>:.J~<i.::i~W... ~loJ ~c:<i._ d?~U;O ~::i..,:~Gi~ c:c:~:li00..u :.=:~.-0 Q..-~U'J_Ul ..,Ul""u :'::<x c:.~:.J 0 ::l u O:~Ul -:-=Ul -~ &.<x 0-..c:_ o.U ""::l :~.~.-..:.JU-U·-loJc:_c:U- ::>U ::>>-.-£I ::lE~::E~£0: ..loJ Ul 0 .. ""W c:o..c:...>0 ~U c:C~0 0 0 c: £I".....c:..c:""~..,Ul UU::>0-C:..c:·00 -..<xu u..c><x~ U >:~0 W 0 ~en..<x~0 (;.. ~.~~ c:.!:iii..I 0 U .. -=c:..c:0 -;::>... 0 ::>0 "---en >-en I %£~01_==:::::=-:- (/) Cl«o -l :ll::« I.LIa. ~ :I: I- Zo ~ %6L9 o N N 9/oc;1£1 M>I .:lO SONVSnOHl Append;x I FIGU,RE G-3 G-24 Table 6 . Monthly Peak Loads,1971 to 1974...- 1971 -1972 1972 -1973 1973 -1974 Peak %Annual Peak %Annual Peak %Annual Month MW Peak MW Peak MW Peak July 143.6 56 146.8 52 162.8 59 Aug.143.3 56 154.5 54 175.9 64 Sept.161.7 63 179.6 64 194.5 71 Oct.185.8 73 209.2 74 224.3 82 Nov.222.8 88 236.3 83 269.6 98 Dec.236.2 93 260.7 92 266.9 97 Jan.254.5 100 283.0 100 274.5 100 Feb.224.5 88 259.6 92 264.2 96 Mar.222.8 87 225.1 80 249.4 91 Apr.176.7 69 196.4 69 201.6 73 May 157.9 62 176.7 62 180.4 66 June 152.1 60 165.2 58 176.2 64 Note:Represents sum of loads for AML&P,CEA,FMUS,and GVEA as published in Alaska Electric Power Statistics,1960-1973,APA, December 1974.Peaks within individual systems may have occurred at different times during the months. ~- Appendix I TABLE G-6 G-25 SYSTEMDAILYGENERATIONCURVEANCHORAGEAREAo36A9N36P9 I36A9N3609 I3EA9N36P9 I36A9N3EP9 I36A9N36P936A9N3EO936~9N36''lSUNDAYMONDAYnJESDAYWEDNESDAYTHURSDAYFRIDAYSATU,qDt.Y250IIIIIiI1II1II!II!III~!i·iII'I';IIIiI;II:I,;.;I'IIIIiiiilTTiIIII'IIIIiITIIII.i'':I.,i.,I,I.'IIIiI~iTIiTI!:1I ,:IJ,I,iI I140'i:iIIIIii!:~iIIiII!ii,i'I:ii',:i::1"I,iIIIi:IIiIII11111,:IiII!IIII:IiiI,!I:'I:iii:I:IiiIIi1II1!Ii!I;IIII'IIi!II1I11IIIIIiIIIiIII;III:II:I,i!'I.j.;;I~I.:_11'!111II1U.L:l!i'1111I[IIIIII11j,11::II,iiiiii1111II:III::I'.I1IIIInol.!.IITII!f!II IIIillI':I'!=R:''IliT--;TIi1i1I,~'~~,r-r-;II!;I~llIlrll~JlW'-'-I-;:-~--r---:1,~iD~·-r~~liq:,:;llIi':11Ii:'Irllld~I!,t:!:iIii'I1mI~~'I,11"iI I~I,I'I220Ii.II.II!U.l':r-T-"-r':-I ,',-, "~:~ttH~mrl:III:~I'~':!,III1III,I'"ii,i1'II11'111IiI1,.,11-•.1.:__..-....•III.Lp__"It'LIII,:II iI'II",,I'I'I11I ";-rIIIII'IIIIIII'II~-,r~•II,,-1I'IIII"1 :IIiii",III1'\111111111";--1I"-+-t'I"""'~I;'hn,11!':lr41~lt~,11,,1',dc!;11I,II'I,','II,,,"11III.Ir1UIULlIn.PJ(-j-·':JI'·i-~·-~h,~Hti~hT1TI:~:HLf~ltI11~~'llU+1ili',II)Ih,'11'1,-:,':1100111lJj~lD11.lit!"II-'"r-I--~L\4";1,~j··tll+II:IU1~~~~I'Ii1~1',1'1,,1"1UI~IIjlLl~l~H'~f"-~~J~IL-1~jIHfM'l!)1i!L~iI1~LLllj.~.1H-:4~.'liIIICLgtfbfili:,'111:1;1II~rI IIltl"i~ri'~i;i-1:n-iJ"jI:"I'~'l~I'IIIIIH'u.uw..11:1,IfITlll1IIIt'II,Iri~i:~1'.VIII III~II II Il'!1I"mu"IIII+'' ,rlI'III,III,'II'11II"I'"I+"W...+~'I...1'iiiIII-1,~,,IIIII'~",~~i'ttd:;::_.~J.liIJlliitfttth'7[trjUf[1tIllli'~jqJ1\il!IiIiIIIii,,1111:'1;;',:-rIIIJ'n'II11iII,IfL14JII+-114+1I;~1l.IiII"ii"Ir1:I~'I~.~~.'.I'I",~III I ''-tJ...:~_~..J:::EI'1I'Ull~.,-'u.u~L :III 'I:D.cember2-8.1913Iitii"TI'illii'.II I '[L""--'iI11I~110~L1•__lII...JJ.U::iiiIIiII!IIT~I ''I,II" 'I'2:I11rt;1.•I-:II'·I]'III II'I!IIIiIIIII,iIIi,'I'~I._•••--.-1.-1'1iIII'I'•I-r150•,IIiII'l'"l,;r,III'I I II ;,II',I!'I,IITII'i:I " ,\;.iIt:'L'~ill----_.ll...IIIIIII'~, " I IIIJ.,,;it!I!!ii'ii,I~iI'ii"I'III",I'ii"::Ii'II,,~,II''-n••Z,L,,'........,I~~~_~'' ,'IJ'L",IH~14li.J-rTLLLlill~lj±''I:'I"'I',I II~IJII(LI_~Ilill,il.1.1I.'1'11:11IiIIIit,:,I'I!I.I~P],IIIiT!II...~nf.--Ll._•I II IJ~._-.lI,i,':;,If,I!:'I"~-1-W~.Lci-'~~.;II,l-L~IIIi!iI:'"IIIITIL "'",-T-,~-l,"',l!;lhF,1I1::'II11+''~.lE,I:",'IU"h:!1bi'm12~HIIlif1ti';li~ij1+11H~!~:~~-~:I~·>;:r-LlH~~~~Jl'!I[11'mo;,~~it~rru';TIwr~~lJm'~:~~,i::II::j~.-l.:tLhU!,I1:1'iUiI~III.....8:--+-~Fl·'IIillHH~~W'I'II'It-··.!-+....L...-:,r'IiI-+--_,,_._.--l--..'_~-i..:...i:lw'jT!I,"I,jj;li:'~:-:++t7~ll..,~_.-T-,',.1l~I~~('7rnIIJ'IIL.I._~_~..~:-i.LL~}:_1Willil!ti.',I:'jj':~il-.L~lJ.,L.:.I1.-.-i--l----...L"L-!-1.IIii'."II,I,'Tl'I•+-II-.""lJ'I,1~I.l)'~~I1-'1-;,,;:'lc4,'::-1:18J''i,,:-,)I::"',o-t•.""I:H,jIlllLLlt;,.J,I1~~lD~kl~t.......L-..-t--+---+.d.L10,.'1+L.L'_L........IIJ.l)Iij~111~I+.J-lJflIiIIIIjI-.l..".illlI~+It=H1I.m:~~4Idjl~..l.:~~l'~Q;j::~::Lt.Uij~t11'1IIji.Iil.]t:-;;J'i+~U1~"--t:~l~rj=+-_-t=.J=r'.0,~_~.1.:L,._I.....d~~j,1',l 'I,j~'II••'I"1',ILLl.Ut"~~-'1-I:./,..:.+IIII!;,L'"I'Irr,-I:~,i'I·-~il;.JI!.'~l~.,[tWillI,"--.-II':-I••J,L•u".';,I,I','..L••_-I--I-_~L-10J!J.,II~L!!L~11_u,IIi!'i[:hIIJI:I"ii.,I'",:IIlLL.,•."~", , I-I.G'lxI+::>........IG'l")::>.p-----------------------------......---:-:-:......-=-=:-:-==-=--=:-:-:-:-:-=~:::~:::----------iI........"0NG'l"O(J)cro;O~fTl0.DAYSOFTHEWEEK}) ))SYSTEMDAILYGENERATIONCURVElANCHORAGEAREA., IliT11'11111::111111111,,1,I,1:1'1::1:,1,11,,1'11!!II!'ill!:;II:IIII!!lllilll:i1li!iIliill'l,i!',II!:;II!I,I,11::11111111:!1,1:11:11I~-4--+'-'-t--+---'--,-+-I'III!,hIiIi!l::ITiTiTITTTITTTTl~I;!!:~~TTiTiTi7ITTfT!lTTTTITTTlTiTlTTi,I,1;-"i~SATURDAYFRIDAYTHURSDAYWEllNESD~,YDAYSOFTHEWEEKTUESDAYMONDAY6P9 I36A,N36P'9I36A9N36P9,36A9N!6P9I36A9N36P9I36A9N36P9I3€.A9N36P9~:~m'Jl''iIi'.I'1;1'.IiiI~iij~1~l11~j:~J~'11~'lit~l'il11'lll~f']I"IIJLlII":',~L~---4~.l.d.-J.._-6_._111.tiJ'I1-.o.-.:w~,-..-4---f---l-IuILII,III,1ill11II[IIII:,Jil~Ii!II:L",~•II..'tttL1"_HL;..J-~----t4-IUI"mUl_""11~II~IH~:'#~IjIIIii.II••.I..JI!IIif~<lJl~~Fth=rf+jEhilileOc'~~"~1$0,IAII:EH~l~140:I,III~IiI I~cI!ORHffi:Z,I~"IIII'"';'.HIH10,I"IHllf.0;Ih70GJ-n:t:>I10I......-0NGJ-o-...,Jc:ro::0:::lI50rrlCl-!6A,N!--'.SUNDAYGJX,~......,N H-r--~I r f-I 1 - I- -- t=-f----.-=tI"- -----....'- -- - C>- OD ...= ...>-<o"on......~ -e--.. '"-f----.-... -~ - = -- - - - -- f--.--~'"I- L-... - C>- OD -~I-...'">-.. - ,.~ -c--+=::>",en ----=-~..I-'"- 0 --j'"- •0 0 I ...0 -' •..0 0....~,... - ,... -- - - - - -f--.- ---- I-- o· --+ ---.:... - --1- --=-1=,=----,t::r - --- ---i=-- .= .----I--~'- -- ---f--------~,-f---- ~I--I- -t="-- ~ W l- (/) ~ Table 7.Monthly Load Factors,1972 and 1973"""- 1972 1973 Energy Monthly Energy Monthly Peak Million Load Peak Million Load Month MW kwh Factor MW kwh Factor Jan.254.5 135.3 72 283.0 153.6 72 Feb.224.5 115.3 76 259.6 127.5 73 Mar.222.8 119.2 70 225.1 125.5 75 Apr.176.7 96.6 76 196.4 105.4 75 May 157.9 87.8 75 176.7 98.5 75 June 152.1 78.5 72 165.2 87.6 74 July 146.8 76.6 70 162.8 89.8 74 Aug.154.5 86.9 75 175.9 96.2 73 Sept.176.9 92.9 72 194.5 100.8 72 Oct.209.2 108.8 70 224.3 122.7 73 Nov.236.3 124.4 73 269.6 144.6 74 Dec.260.7 143.3 74 266.9 147.0 74 Note:Represents sum of loads for AML&P,CEA,FMUS,and GVEA as published in Alaska Electric Power Statistics,1960-1973, APA,December 1974. Appendix I TABLE G-7 G-29 Studies for Alaska Power Survey The power requirement studies for the new FPC Alaska Power Survey are summarized in the May 1974 report of the Technical Advisory Committee on Economic Analysis and Load Projection.These studies included review of previous reports and recent load estimates prepared for the power system in the state,analysis of present and future trends in power consumption,and regional estimates of future power requirements through the year 2000.These regional estimates were developed as a range of future requirements depending upon assumed levels of change in the Alaska population and economy.All of the estimates assumed substantial reduction in growth rates for power demands after 1980 would be achieved through conservation measures. The power survey regional estimates included Railbelt area loads in the regional totals for the Southcentral and Yukon regions.Figure 5 shows the regional boundaries.For 1972,utility requirements immediately accessible to an interconnected Railbelt system amounted to about 96 percent of total utility loads for the two regions.Thus the regional totals are reasonably representative of Railbelt system requirements. The regional estimates also included evaluations of likely new industrial power requirements --timber,mineral,oil and gas,etc.--many of which would be remote from a Railbelt system,for the foreseeable future. Table 8 summarizes regional utility system requirements for the 1960 to 1972 period as presented in the power survey.This analyses indicated Railbelt utility requirements were increasing at an average rate of 14 percent annually.In 1972,Railbelt utility loads totaled 1.3 billion kilowatthours, or about 80 percent of statewide requirements for the year. Total 1972 Railbelt loads,including utility,national defense,and self- supplied industrial loads,were about 2 billion kilowatthours,or 77 percent of statewide total requirements for the year. Tables 9 and 10 summarize the regional estimates from the power survey through the year 2000 for utility system requirements,and for total requirements including national defense systems and industrial requirements. The power survey studies reflect future assumptions ranging from fairly limited to rather rapid development of the Alaska resources and economy. On the basis of the power survey mid-range estimates,expected increments in regional utility and total requirements are as follows: Appendix I G-30 - ))400~200ScaleinmillS50100I,ALASKAPLANNINGREGIONSUNITEDSTATESDEPARTMENTOFTHEINTERIOR,ALASKAPOWERADMINISTRATIONGULF!OFALASKA.--------------l---------(J-'..;---..~///~--.I---i180"/I~"1JUA../.>3..../,...:/-~~__;i_//;~~--~~_/~"I0-~...~~~/G'l"T1)::>I........"<..oJG'l"-,cCl>;;CJ~rr10-.....G'l><&,........1164"160"1!l8'152"148"144"./-140"136"132"I Table 8.Utility System Requirements,1960-1972 - Year Southeast Alaska Southcentra1 Alaska Yukon (In terior) Remainder of State Y State Total 2/ Annual Gross Generation,Million kwh 1960 104 234 86 7 431 1961 111 264 89 11 475 1962 120 294 93 12 520 1963 129 329 102 14 573 1964 141 362 110 15 628 1965 148 452 117 17 735 1966 160 510 132 20 821 1967 165 560 145 22 891 1968 177 633 171 25 1,007 1969 185 708 198 29 1,120 1970 202 831 243 35 1,311 1971 217 990 276 43 1,526 1972 3/229 1,037 307 46 1,620 Portion of StateV':ide Requirements,(%) 1960 24 54 20 2 100 1966 19 62 16 2 100 1972 14 64 19 3 100 Rates of Growth,(%per year) 1960-1966 1966-1972 7.5 6.2 13 .9 12.5 7.5 15.1 19.1 14.9 11.4 12.0 1/Arctic,Northwest,and Southwest Regions. 2/Totals may not balance due to rounding. 3/1972 data preliminary. Appendix I TABLE G-8 G-32 Table 8.Utility System Requirements,1960-1972 (Cont'd) Other Growth Indications Factor Population growth,1960-1972: 1.Statewide Total residential population Total civilian population 2.Railbelt Total residential population Total civilian population Annual Growth Rate 3.0% 3.7% 3.6% 4.5~> Railbelt area utility power requirements,1960-1971 growth: 1.Total requirements Kwh sales Number of customers Kwh/customer 2.Residential sales Kwh sales Number of customers Kwh/customer 14.0% 6 .O~. 7.3% 13.8% 6.5% 7.0% Source:Alaska Power Survey,Technical Advisory Committee on Economic Analysis and Load Projection. /-Append i x I G-33 Gl-l):>IJ::>-owco-o.j:::>,rorTl::::lTable9.RegionalUtili!yLoadEstimates,1972-20000..Gl-->.I><1..0.......ActualRequirementsEstimatedFutureRequirements1972.198019902000PeakAnnualPeakAnnualPeakAnnualPeakAnnualDemandEnergyDemandEnergyDemandEnergyDemandEnergyRegion1000KWMillionKWH1000KWMillionKWH1000K\\'MillionKWH1000KWMillionKWHHigherRateof'GrowthSouthcentral2241,0376802,990.1,6407,1903,59015,740Yukon(Interior)693072008704602,020970~230---------Total2931,3448803,8602,1009,2104,56019,970LikelyMidRangeofGrowthSouthcentral6102,6701,2205,3502,2209,710~--Yukon(Interior)1807803401,5006002,610-----Total7903,4501,5606,8502.82012,320LowerRateofGrowthSouthcentral5302,3409804,2901,4706,430Yukon(Interior)1606802701,2003901,730-------Total6903,0201,2505,4901,8608,160Note:Estimatedfuturepeakdemandbasedon50percentannualloadfactor.Source:AlaskaPowerSurvey,TechnicalAdvisoryCommitteeonEconomicAnalysisandLoadProjection.)~ )Table10.RegionalTotalLoadEstimate,1972-2000)RegionSouthcentralYukon(Interior)TotalSouthcentralYukon(InteriorTotalActualRequirements~stimatedFutureRequi.rements1972198019902000PeakAnnualPeakAnnualPeakAnnualPeakAnnualDemandEnergyDemandEnergyDemandEnergyDemandEnergy1000KWMillionKWH1000KWMillionKWH1000KWMillionKWH1000KWMillionKWHHigherRateof-Growth•3171,4659905,0205,02030,7607,19040.8101155423301,6107603,9801,3907,000--4322,0071,3206,6305,78034,7408,58047.810-~LikelyMidRangeofGrowth7903,7901,5307,4003,04015,3002801.3104702,2709104,6101,0705,1002,0009,6703,95019,910.LowerRateofGrowthSouthcentralYukon(Interior)Total6502509003,0401,1404,1801,1603701,5305,4301,7607,1901,7905302,3208,5102,54011,050Ci>--l~I)::>"'0wc:o"'OUlrrof'Tl~0-Ci>......I><......0.......Note:Assume80percentannualloadfactorforindustrialrequirements;50percentforutilityrequirements.Higherestimateincludesnuclearenrichmentfacilityin1980'swithrequirementsof2.5millionkilowatts.Source:AlaskaPowerSurvey,TechnicalAdvisoryCommitteeonE<.:onomicAnalysisandLoadProjection. Period 1972-1980 1980-1990 1990-2000 Period 1972-1980 1980-1990 1990-2000 South central and Yukon Utility Load Increments Peak Demand MW 497 770 1,260 Southcentral and Yukon Total Load Increments Peak Demand MW 638 930 1,950 Factors Influencing Power Demands Annual Energy Million Kwh 2,106 3,400 5,470 Ann ual Energy Million Kwh 3,093 4,570 10,240 This section will discuss some of the factors that will influence future power demands in the Railbelt area.In many cases,direct impact on power demands cannot be quantified with any degree of accuracy, but all of the factors will be considered in the assumptions for future requirements. Population Change During the 1950-60 decade Alaska 1 s population increased some 76 percent.Th e following decade,although adding over 76,000 persons, the net increase was 34 percent.l/Increases for the South central and Interior regions were 117 and 50 percent;and 114 and 16 percent respecti vely . 1/This may be compared with a net increase of the far West region of 14.7 percent,the Mountain Region with 15.9 percent and the United States with 13.8 percent,Review of Business and Economic Conditions.- Appendix I G-36 ~-Alaska Population 1950 -1970 a/and 1974 b/ Change Change Change Year Alaska No.%So.Central No.%Interior No.% 1950 128,643 50,909 23,008 1960 226,167 97,524 75.8 108,851 58,758 117.3 49,128 26,120 113.5 1970 302,647 76,480 33.8 163,758 54,907 50.4 56,799 7,671 15.6 1974 351,159 48,986 16.2 194,569 31,777 19.4 67,315 10,516 18.5 Each year from 1960 to 1970,Alaska and the Southcentral and the Interior regions added an average of some 7,600;5,500;and 750 persons respectively. Since 1970,these same areas are estimated to have annually averaged an increase over 12,200;7,900;and 2,600. These figures predate start of construction of the Alyeska pipeline. Discounting direct employment on pipeline construction,Railbelt population has been increasing at a compound rate of around 3.5 percent per year. Most planners expect continued rapid increase for at least the next few years. Economic Growth Population change is of course related to economic activity and employment opportunities.Historically Alaska's economy was based on furs,gold and copper.Its modern economy has relied on fisheries,forestry and government services.Presently Alaska's growth economy is being driven by the exploration and development of the northern,(primarily Arctic Slope)oil and gas fields,the construction of the Alyeska oil pipeline and transhipment facilities at Valdez;and the accompanying growth in support services and facilities at Anchorage,Fairbanks and other towns along the pipeline route.Additional impetus is coming from state a/Review of Business and Economic Conditions,University of Alaska. Institute of Social.Economic and Government Research,Dec.1971, Vol.VII,No.5. ~/Derived from Current Population Estimates ~Census Divisions, July 1,1974,Alaska Department of Labor,Research Division. ,-- Appendix I G-37 expendi tures,construction of local infrastructure,expansion of Alaska IS service industry,and activities associated with the Alaska Native Claims Settlement Act (ANCSA). Some of these activities such as the construction of the oil pipeline and transhipment facilities have a limited time in which their effect will continue to provide economy expansion.For example,the huge pipeline construction force is expected to decline very rapidly on completion of the actual pipe laying in late 1976,and longer term employment for operating the line will involve relatively few jobs. Other factors such as ANCSA can be expected to have very long term effects as the regional and village corporations use their capital,land and resources to economic advantage. There are very strong pressures for expanding oil and gas exploration and development in Alaska,representing a very complex set of interests at the national,state,and local levels.Several areas on the Alaska Outer Continental Shelf and Naval Petroleum Reserve #4 are very high priorities in the national programs directed to energy self sufficiency.State interest and involvement includes possible additional leasing (Beaufort Sea and others),recognition that leasing and royalty revenues will likely be the major source of state income for the foreseeable future,and decisions on state royalty oil and gas.Some of the Native Corporations have oil and gas exploration programs underway.If reserves are found,there will be strong pressures for development for these lands too. Generally,it must be assumed that the oil and gas developments will continue to be a major factor in the Railbelt and state economy for the foreseeable future,and that additional major oil and gas developments impacting the Railbelt are probable within the next few years,including substantial expansion of the present petrochemical industry. Other factors which will continue to support economic growth in the Railbelt include the Capi tal relocation I and any further developments in other industries including tourism,forestry,mining,and agriculture. No one is suggesting that all of the above will occur in the short term. Each,however,has a possibility and any combination of the above events must increase the population of Alaska and the energy requirements. AppendiX I G-38 - Changes in Use of Electric Energy Nationally,electric energy consumption has been expanding at a compound rate of around seven percent per year.This compares with around a four percent increase in total energy USe.These increases correlate with or exceed trends in national gross product and substantially exceed rates of population growth. :Many factors can be cited in at least partial explanation of these trends high productivity of electric energy in industry,increasing affluence, low cost of energy,and so forth. Preliminary statistics indicate that total U.S.energy consumption during 1974 declined by about two percent and that electric energy production for the year showed no growth over 1973.This was the first full year of widespread concern for energy conservation,and results of the conservation programs are reflected in the changes. However,the changes also reflect a large increase in relative cost of energy,a deep economic recession with high unemployment and large amounts of idle industrial capacity,and generally mild winters. For Alaska,1974 was not a recession year.Energy consumption continued to increase rapidly in the state,including increases exceeding 12 percent in electric energy requirements for the major Railbelt utilities. Data presented previously showed that increases in electric demands for the Railbelt reflect both increases in numbers of customers and increases in use per customer. It is reasonable to assume that electric energy will be substituted for many direct uses of oil and gas in the future.This substitution is one of the few major options available for reducing dependency on oil and natural gas. Only very rough estimates are available on the extent to which such substitutions may be desirable.Data presented in the power survey showed electric energy accounted for only 13 percen t total energy used in Alaska in 1971,and that as of 1972,over 60 percent of the state's electric requirements were derived from oil and gas.In contrast, the Pacific Northwest derives over 90 percent of its electric energy from hydro power,and electrici ty accounts for about 40 percent of Appendix I G-39 total regional energy use.It is APA's judgement that in the long term, electric energy will provide a similarly large share of total energy requirements in the Railbelt area,if alternative power sources of coal,hydro,and nuclear are developed.Assuming no growth in overall energy use,this would involve a three-fold increase in electric energy requirements. The cold climates,especially in the Interior,provide additional incenti ve to substitute electric energy for direct use of fossil fuels.For example, an all electric economy for the Fairbanks area would substantially reduce future problems with air pollution,fog,and ice fog. Appendix I G-40 - - 1975 Estimates of Future Power Requirements This section presents future power requirement estimates developed for the current evaluation of the Upper Susitna Project.Work for the new estimates consisted of:(1)a review of the previous data and data from the power survey in light of new data for the years 1973 and 1974;(2)consideration of current regional and sectional trends in energy and power use;and (3)preparation of a new set of load estimates reflecting this most recent data. The new analyses generally indicate that major premises for the power survey load estimates remain valid.Changes include the update for the most recent estimates and reducing the regional estimates from the power survey to reflect areas that could be served directly from an inter- connected Railbelt system.This latter step eliminated loads for remote cities and villages as well as potential industrial loads for these remote areas. For 1973 and 1974,the Anchorage area utilities energy demand increased 15.2 percent per year and peaking requirements increased 12.6 percent per year.The Fairbanks'utilities energy demand increased only 3.9 percent while the peaking requirement increased 7.4 percent.The smaller increase in the Fairbanks area is assumed due to the large buildup in anticipation of the oil pipeline construction,and then a subsequent delay of construction start until late 1974. The new estimates are summarized in Table 11 and Figure 6.Indicated load increments,by decade,are: Increments of Utility Power Requirements,1,000 KW Higher Estimate Mid-Range Lower Estimate 1974-1980 440 370 320 1980-1990 1,140 740 560 1990-2000 2,280 1,180 600 1974-2000 2,280 2,290 1,480 Increments of Total Power Requirements,1,000 KW 1974-1980 1980-1990 1990-2000 1974-2000 Higher Estimate 540 3,960 2,300 6,800 Mid-Range 420 800 1,500 2,720 Lower Estimate 340 600 660 1,600 Appendix I G-41 Table11.EstimatedUtility.NationalDefense,andIndustrialPowerRequirements(j)-j~I~\:l~cx;J-ON'(Drt1:::la..(j)......IX................TypeofLoadAreaActualRequirementsEstimatedFutureRequirements1974198019902000--PeakAnnualPeakAnnualPeakAnnualPeakAnnualDemandEnergyDemandEnergyDemandEnergyDemandEnergy1000kwMillion/kwh1000kwMillion/kwh1000kwMillion/kwh1000kwMillion/kwhNationalDefenseAnchorageFairbanksTotalIndustrialAnchorageFairbanks1/AnchorageFairbanks1/AnchorageFairbanks1/33155351704019045220.41197452205024055260--------743528039090430100480~-.HighRateofDevelopmentAssumed10451007102,91020,3902,92020,460---------Mid-RangeDevelopmentAssumed50350100.7104102,870----------LowDevelopmentAssumed20140503501007101/Roundstolessthan10MWNote:Industrialdevelopmentdoesnotassumepipelinepumping.)~ )Table11.EstimatedUtility,NationalDefense,andIndustrialPowerRequirements(Cant))G>)::>I-0~-oWCD~0.......x.......TypeofLoadAreaUtilitiesAnchorageFairbanksTotalAnchorageFairbanksTotalAnchorageFairbanksTotalActualRequirementsEstimatedFutureRequirements1974198019902000PeakAnnualPeakAnnualPeakAnnualPeakAnnualDemandEnergyDemandEnergyDemandEnergyDemandEnergy1000kwMillion/kwh1000kwMillion/kwh1000kwMillion/kwh1000kwMillion/kwh-HighRateofGrowth2841,3056502,8501,5706,8803,43015,020833301607003801,6608003,500-----------3671,6358103,5501,9508,5404,23018,520LikelyMid-RangeGrowth5902,5801,1905,2102,1509,4201506602901,2705102,230-----7403,2401,4806,4802,66011,650LowerRateofGrowth-5502,4101,0104,4201,5006,5701406102401,0503501,530-- ------6903,0201,2505,4701,8508,100 G)::>I"'0~"'O~ro:::::l0.......x.......Table11.EstimatedUtility,NationalDefense,andIndustrialPowerRequirements(Cant)TypeofLoadAreaActualRequirementsEstimatedFutureRequirerr.ents1974198019902000PeakAnnualPeakAnnualPeakAnnualPeakAnnualDemandEnergyDemandEnergyDemandEnergyDemandEnergy1000kwMillion/kwh1000kwMillion/kwh1000kwMillion/kwh1000kwMillion/kwhCombinedUtility,NationalDefense,andIndustrialPowerRequirementsHigherGrowthRateAnchorageFairbanksTotal3271244511,5055272,3027852059903,7309204,6504,5204304,95027,4601,90029,3606,3958557,25035,7003,76039,460AnchorageFairbanksTotalAnchorageFairbanksTotal)LikelyMid-RangeGrowthRate6753,1001,330195880340---8703,9801,670LowerGrowthRate--6052,7201,100185830290-----7903,5501,3906,1101,5107,6204,9601,2906,2502,6055653,1701,6454052,05012,5102,49015,0007,5001,7909,290) )ESTIMATEDFUTUREPOWERREQUIREMENTS1974-2000I.PEAKLOADREQUIREMENTS40,00030,00020,00010,000)100'IA.PA.-September1975I19657075808590952000YEARGJ"T])::>I--0..".G"J-oU1Cro;:0::::::1rrl0..-'.G"JXI0"\_,-'3:5000:E4000Io3000~32000~~W1000a.500400300200Note:Includesestimatedpeakloadrequirementsforutility,nationaldefense,andindustrialpowersystemsintheAnchorage-CookInletandFairbanks-TananaValleyareas. Note:Includesestimatedannualenergyrequirementsforutility,nationaldefense,andindustrialpowersystemsintheAnchorage-CookInletandFairbanks-TananaValleyareas.ESTIMATEDFUTUREPOWERREQUIREMENTS1974-20002.ANNUALENERGYREQUIREMENTS40,000\:=-]30,00020,000i10,000~Zo5000:J4000~3000,b2000a::WZW...J<X:::::>Z~OOZ400<X:IN~xI0".......IG:l,,:t:>Io-l"'Cl.."~"'ClO"cro;;o~me........300200,952000908085YEAR75701001I1965A.P.A.-September1975I~ --- With allowances for reserves and plant retirements.the indicated new capacity requirements by the year 2000 range from about two to eight million kilowatts with a mid-range estimate of over three million kilowatts. Rates of increase in utility power requirements assumed for the future estimates are shown below: Estimate 1974-1980 1980-1900 1990-2000 Higher Range 14.1%9%8% Likely Mid-Range 12.4%7%6% Lower Range 11.1%6%4% It bears repeating that the assumed growth rates after 1980 are substantially below existing trends and that they assume substantial savings through increased efficiency in use of energy and conservation programs. The estimates for the National Defense requirements are premised on the 1974 power use for the major bases and an assumed future growth of approximately one percent per year.These estimates are lower than presented in the power survey data.reflecting trends in 1973 and 1974. The estimates for future utility requirements cover the same load sectors as now supplied by Alaska utility systems.This includes most light industry and industry support services.The utility estimates do not include allowances for industrial requirements for major new resource extraction and processing.new energy intensive industries.or heavy manufacturing. The power survey studies included a review of potential new developments in the energy.mineral.and timber fields and a set of assumptions on individual developments considered likely through the year 2000. Basically.the estimates involved selecting a few developments considered most likely to occur from among the more promising potentials and rough estimates of the power requirements that would be involved. For this study.the power survey assumptions were screened to include only those developments which could be readily served from an interconnected Railbelt power system.This eliminated many potential new industrial loads listed in the Survey.particularly remote mining developments in the Yukon region. Appendix I G-47 Tables 12 and 13 summarize assumed new industrial power requirements for th is report. The basic assumptions incorporated in these new estimates are summarized below.In most cases,the assumptions are similar to those adopted for the power survey: 1.It is generally considered that the Railbelt area population will continue to grow more rapidly during the study period than the national average. 2.Utility statistics indicate individual customers'electric energy consumption has been increasing six to seven percent per year.However,all of the load estimates assume that saturation levels for many energy uses will be reached and that rates of increase for most individual uses will decline during the 1980's and 1990's.This reflects assumed effects of major efforts to increase efficiencies and conserve energy for all uses. 3.Rapid growth in the Railbelt area will continue through the balance of the 1970's,with economic activity generated by North Slope oil and gas development being a major factor. 4.Future additional energy systems,potential mineral developments, petroleum processing,and development of a petrochemical industry will all be very influential in use of electrical energy through the end of the century. 5.Major economic advances for all of Alaska and especially for the Alaska Native people should be anticipated as a result of the Alaska Native Claims Settlement Act. 6.There may be substantial substitution of electricity for direct use of oil and gas if the electricity is from other sources. Load factors assumed were the same as for the power survey--utility systems,50%;industrial loads,80%;and national defense,55%.The 50%and 55%are further supported by the data in Table 3.The 80%is an assumption based on higher utilization of generation equipment by industry.Minor differences may be reflected in the table due to combining and rounding. The concept of range It attempts to balance conservation trends. Appendix I G-48 estimates presented in the power survey is continued. the population and the growth factors with increasing The "higher"range anticipates significant new - Table 12.Assumed Industrial Development INDUSTRY Kenai Peninsula: Chemical Plant: RATE OF GROWTH Low ASSUMPTION Existing,with planned expansion by 1980, then,no change to 2000. Mid Existing,larger eXPansion assumed by 1980, continued expansion to 2000. High Existing,largest yet expansion assumed by 1980,larger expansion to 2000. LNG Plant: Refinery: Timber Processing: Low Mid High Low Existing,with no change assumed to 2000. Existing,no change before 1980,steady expansion thereafter. Existing,expansion assumed before 1980 and continuing to 2000. Existing,plus same assumptions as LNG plant. Small start before 1980,expansion to high value by 2000. Mid Larger start before 1980,expansion to high value by 1990. High Largest start before 1980,no change to 2000. Appendix I TABLE G-12 G-49 Table 12.Assumed Inc1ustrial Deve]opmen t (continued) - IHDOOTRY Other Vicinities: Mining and Mineral Processing: RATE OF GROWTH Low ASSUMPTION Start-up after 1980,five-fold expansion by 2000. Mid Start-up by 1980,five-fold expansion by 1990,double by 2000. High Large start-up by 1980,double by 1990, no change to 2000. LNG Plant:Low Start-up after 1980,no change to 2000. Mid Start-up before 1980.no change to 2000. High """"" "" " Beluga Coal Gas ification:Low Pilot project power between 1990 and 2000. Mid Pilot project by 1990,full operation by 2000. High Pilot project before 1980,full operation by 1990,no change to 2000. Nuclear Fuel Enrichment: Timber: High Low Start at full operation before 1990,no change to 2000. Start-up after 1980,full operation by 2000. Mid Start-up before 1980,full operation by 1990, no change to 2000. High Full operation start-up before 1980,no change thereafter. New City:Low Initially loaded after 1980,load tripled by 2000. Mid Initially loaded before 1980,tripled by 1990 2 1/3 expansion by 2000._. Appendix I G-50 High Larger initial load before 1980,2 1/3 expansion by 1990,no change to 2000. energy and mineral developments from among those that appear most promising. The "lower "range generally assumes a slackening of the pace of development following the completion of the Alyeska pipeline.The "m id-range ll appears to be a reasonably conservative estimate. With the exception of the annual large load for a nuclear enrichment facility (2500 MW in the 1990 and 2000 "high range"estimates only)all of the assumed new industrial loads are considered very conservative.The main purpose of including the nuclear enrichment assumption is to illustrate that order of magnitude of loads for large energy-intensive uses. Very rough estimates for requirements that might be anticipated for a new capital city are also included in Table 12. The estimates do not assume major loads associated with OCS developments or very large petrochemical industries.Similarly,they do not assume rapid acceleration of mining and mineral processing. Copper Valley Power Requirements The Copper Valley Electric Association provides power at Valdez and Glennal- len.Power requirements are relatively small,but recent rates of increase have been large because of activity related to the Alyeska pipeline and terminal construction. Existing Situation CVEA energy requirements have increased at an average annual rate of 10 percent from 5.6 million kwh per year in 1965,the first year CVEA served both Glennallen and Valdez,to 14.4 million kwh per year in 1974. The 1974 peak load for the two towns was 3.5 MW.Combined installed capacity was 6.1 MW (all diesel). CVEA recently installed 3.6 MW in Valdez and has 5.2 MW scheduled for Glennallen during 1975 with an additional 6 MW proposed for Valdez in 1976 and again in 1978.CVEA has under study a small hydro project (Solomon Gulch)and a potential intertie between Gtennallen and Valdez. Future Utility Loads The most recent estimate of utility loads is presented in an October 1974 study prepared for CVEA .Y The study estimated near future loads would peak at 9 MW and 46 million kwh upon construction completion of the pipeline, y Copper Valley Electric Association,Inc.15 Year Power Cost Study Hydro/Diesel.Robert W.Retherford Associates,October,1974. Appendix I G-52 - - the pipeline terminal,and an electrical interconnection bet",reen Valdez and Glennallen in 1978.The loads were estimated to level off for a few years at that time.By 1989,the study estimated the loads at 15 MW and 75 million kwh.It was envisioned that CVEA would furnish energy to the construction camp,the pipeline refrigeration station,and the utility-type loads at two oil pipeline pumping stations.Alyeska Pipeline Company estimated these loads would amount to 21.8 million kwh annually. APA estimated CVEA power requirements based on rate of growth assumptions similar to those used for estimating the Anchorage and Fairbanks area needs. The estimates are shown in the following tabulation: 1980 1990 2000 Energy Energy Energy Million Peak Million Peak Million Peak Growth During Period kwh MW kwh MW kwh MW High 32 7 77 18 169 38 Mid-Range 29 7 58 13 105 24 Lower 27 6 49 11 73 17 Should the Valdez area become a major manufacturing or oil processing area,the above estimates of utility loads would be much too low. Industrial Loads Current industrial loads include the construction camps for the pipeline terminal and pumping stations.An oil-fired steamplant will supply electric requirements and process steam at the terminal. These are relatively small loads. The concept of using electric power for oil line pumping requirements has been advanced in previous studies.For a variety of reasons, including economics and absence of a strong area transmission system,this plan was not attractive to the pipeline company. All recognize that a substantial savings in oil could be accomplished if the pipeline were electrified.and if the power were derived from another source such as hydro or coal.Total requirements for pipeline pumping south of the Yukon River were estimated at 225,000 KW in an APA study (969). Appendix I G-53 The concept of utilizing electricity to displace fuels would bear further attention if an Alaska route is selected for transporting natural gas from Alaska's North Slope.The substantial amount of gas needed for compressor and refrigeration stations and for liquefying the gas could be saved by substituting electric power.Informal estimates from the El Paso Natural Gas Company indicate requirements of up to 900 MW if an Alaska gas line and LNG plant were powered by electricity. Assuming an 80 percent plant factor,this would amount to around 6 billion kilowatt hours annual energy.A large portion of the load would be at tidewater at the LNG plant. The availability of large amounts of oil and possibly natural gas at ports on the Gulf of Alaska further suggests the possibility of establishing refineries or petroleum plants in the area. Industrial loads associated with oil and gas pipelines and other potential industrial loads in the Prince William Sound Area have not been considered in assessments of Upper Susitna power markets and financial feasibility of the project. Criteria for Capacity and Energy Distribution Reservoir and powerplant capacity criteria are premised on expected use of the project to meet power demands.This section discusses the data and assumptions incorporated in the capacity criteria for the Upper Susitna Project. The basic approach involves a set of monthly energy distribution assumptions which are used to size the project reservoirs and to determine annual firm energy production from the project.The powerplant capacity assumptions reflect the capacity needed to market the project power. Energy Distribution It is assumed that the energy requirements from the hydroelectric project will be proportional to total system energy requirements on a monthly basis for any given year. Table 14 summarized 1970-1972 monthly energy distribution for the area utilities,expressed as a percent of annual energy requirements.The table also shows energy distribution assumptions used in previous hydro- electric studies in the area. Appendix I G-54 - Table 14.Monthly Energy Reguirements as Percent of Annual Reguirements 1961 1971 1970-1972 Reconnnended Devil Brad127 Utili~for Current MONTH Canyon 1/Lake-Loads l/Studies 4/ Oct.8.9 8.3 7.9 8.0 Nov.9.4 9.1 8.9 8.8 Dec.10.4 11.0 10.2 9.7 Jan.9.3 9.9 11.3 10.6 Feb.8.1 9.0 9.2 9.0 Mar.8.3 8.4 9.8 9.4 April 7.7 7.8 8.0 8.1 May 7.6 7.4 7.2 7.5 June 7.2 7.2 6.5 6.9 July 7.4 7.2 6.4 6.9 Aug.7.7 7.2 7.1 7.4 Sept.~7.5 7.5 7.7 Total 100.0 100.0 100.0 100.0 SEASONAL Oct.-Aug. May-Sept. 62.1 37.9 63.5 36.5 65.3 34.7 63.6 36.4 1/USBR Feasibility report. £/Corps draft report,1971 2/Combined loads of CEA,AML&P,GVEA,FMUS,for period Oct.1970 -Sept.1972. ±/Assumes total requirements consisting of 25%industrial loads and 75% of the above combined loads of the four major utilities. Appendix I TABLE G-14 G-55 For the current studies,it assumes that future load patterns will be modified somewhat as a result of industrial requirements that would tend to have a fairly even energy distribution throughout the year.As indicated on Table 14,this assumption modified seasonal distribution of energy by less than two percent. As used in the project operation studies,firm energy capability is deter- mined for any given combination of reservoir capacity as the amount of energy that can be delivered under critical year runoff conditions using the assumed monthly energy distribution.Under these assumptions,substan- tial amounts of secondary energy are available in most years,and a significant part of the reservoir capacity is used only for long term storage to increase flows in the lowest runoff years. These methods are quite traditional for planning studies,although it is recognized operations would not follow precisely the same patterns.The project would always operate in conjunction with other thermal and hydro- electric plants in the interconnected system.Energy demands on the Susitna Project would vary because of changes in fuel supplies,generator maintenance schedules,and other factors.It is also anticipated that actual project operations would be pointed more towards maximizing annual energy production rather than long term storage to augment flows in the critical year.However,the planning study assumption provides a reasonably conservative estimate of average annual firm energy and an adequate basis for determining merits of the project. Capacity Requirements As discussed previously,the utility systems have had combined annual load factors slightly over 50 percent in the past few years.This is premised on non-concurrent peaks in separate systems,so actual load factors would be somewhat higher due to diversity.Data presented earlier also shows that mid-summer peaks have been running about 60 percent of mid-winter peaks.that monthly load factors generally exceed 70 percent, and that winter and summer load shapes are quite similar. It is anticipated that there will be a trend towards somewhat higher annual load factors in the future.In addition to benefiting from any load diversity in the interconnected system,peak load management (including such action as peak load pricing)offers considerable opportunity for improving load factors,which in turn reduces overall capacity requirements for the system in any given year.For planning purposes,it is assumed that the annual system load factor will be in the range of 55 to 60 percent by the latter part of the century. Appendix I G-56 - System capacity requirements would be determined by winter peak load requirements,plus allowances for reserves and unanticipated load growth. The lower summer peaks provide latitude for scheduled unit maintenance and repairs. Daily peak load shapes for the system indicate a very small portion of the capacity is needed for very low load factor operation.It is expected that some of the gas turbine capacity which is now used essentially for base load will eventually be used mainly for peak shaving purposes; that is,it will be operating during peak load hours for the few days each year when loads approach annual peak,and operating in standby reserve for the balance of the year. It is expected that reliability standards will be upgraded as the power systems develop.This will likely include specHic provisions for maintain- ing spinning reserve capacity to cover possible generator outages as well as substantial improvements in system transmission reliability. Examination of the winter daily and weekly load curves (Figure 4)indicates the base load portion is about 70 percent of total load and the peak load is about 30 percent of total load.Load factor for the peak portion is about 50 percent,and winter weekly load factors are on the order of 80 percent. An annual plant factor of 50 percent has been selected for the Upper Susitna Project.This is largely a judgment factor reflecting the following cons iderations: 1.This assumption would insure capability to serve a proportional share of both peaking and energy requirements throughout the year,and adequate flexibility to meet changing conditions in any given year. 2.Any significant reduction in this capacity could materially reduce f1exibility. 3.There does not appear to be a significant market for low load factor peaking capacity within the foreseeable future.There is likelihood that load management and addition of some industrial loads will increase the overall system load factor in the future,and it is expected that several existing and planned gas turbine units could eventually be used for peak shaving. Appendix I G-57 4.It is recognized that the mode of operation for the hydro will change through time.In the initial years of operation,it is likely that the full peaking capacity would be used very infrequently.For example,the mid-range estimated system peak load for the year 2000 is 3,170 MW.Assuming load shapes similar to the current Anchorage area loads,the winter peak week would require about 2,000 MW of continuous power to cover the base loads and about 1,200 MW of peaking power.Load factors of the peak portion would be about 50 percent. Appendix I G-58 - Part VI AL TERNA TIVE POWER SOURCES The proposed Upper Susitna hydroelectric development would provide large blocks of load factor power for the Railbelt area starting in about 1985.This section discusses alternative means of providing equivalent power supplies.It concludes that conventional coal-fired steamplants represent the most logical alternative to major hydro development for this time period. The evaluation of alternatives is intended to help provide the basis for selecting the most appropriate course of action for meeting future demands. Reliability,prices,and environmental impacts are important aspects of such a comparison.Additionally,the range of alternatives must include only those for which technology is available (or may reasonably be expected to be available in this time frame). Power Survey Studies The studies for the new power survey includes fairly detailed analysis of generation costs for steamplants (coal and oil or gas-fired),gas turbines. and diesel engines.Key assumptions relative to the Railbelt were that 0)fuels suitable for use in gas turbines would be available in 1980 at a cost of from 60 ¢to $1.00 per million Btu I s at 1973 price levels (no inflation),and (2)that coal for steamplants would be available at a cost of from 30¢to 60¢per million Btu's in 1980 at 1973 prices.Table 15 summarizes the alternative generation costs presented in the survey. Solar,wind,and tidal power were not considered as major planning alternati ves . Some very rough data on installation costs for nuclear power were presented.Most planned developments in the South 1148 11 are in the 1000 MW class;reports at the time were indicating plant investments in the range of $500 to $600 per kilowatt;that comparable Alaska costs might be on the order of $900 to $1000 per kilowatt;and that smaller plants would likely be more costly. Appendix I G-59 Table 15.Future Generation Costs 1/- 1.Diesel-Electric (IC)Powerplants @ 50%Annual Load Factor (Public Financing) Plant size,~IW In ves tmen t cos t , $/kw 0.2 130 1.0 130 5.0 160 10.0 160 Uni t generation cost,including fuels,mills/kwh: (Based on:11,200 Btu/kwh 10,370 Btu/kwh) Fuel cost @ 20¢/gal.30.4 25.8 23.1 21.9 Fuel cost @ 25¢/gal.34.4 29.8 26.8 25.6 Fuel cost @ 30¢/gal.38.4 33.8 30.5 29.3 Fuel cost @ 40¢/gal.46.4 41.8 37.9 36.7 Notes:Costs would be higher for remote locations;alternate assumptions of private financing increases unit costs from 2.1 to 2.6 mills per kilowatthour. 2.Gas Turbine Powerplants @ 50%Annual Plant Factor (Public Financing) Plant size,~ Investment cost,$/kw 20 135 35 135 50 167 500 150 Unit energy costs,including fuels,mills/kwh: Fuel cost @ 20¢/I\1Btu 7.61 7.31 7.75 7.22 Fuel cost @ 30¢/MBtu 9.11 8.51 8.95 8.42 Fuel cost @ 60¢/MBtu 13.61 12.41 12.55 12.02 Fuel cost @ $1.OO/MBtu 19.61 17.61 17.35 16.82 Fuel cost @ $1.41/MBtu 25.91 23.07 22.39 21.86 (oil @ 20¢/gallon) Equipment and heat rate assumptions: 20 ~open cycle,15,000 Btu/kwh 35 ~open cycle,13,500 Btu/kwh 50 MW regenerative cycle,12,000 Btu/kwh 1/Source:Advisory Committee Studies for FPC Alaska Power Survey. Appendix I TABLE G-15 G-60 Table 15.Future Generation Costs (cant.) 3.Coal-Fired Steamplants,Railbelt Area,50%and 80%Plant Factor (Public Financing).(Assumed heat rate of 10,000 Btu/kwh) Plant size,MW 100 200 500 Investment cost,$/kw 496 456 373 Unit energy costs including fuels,mills/kwh: 50%Plant Factor Plants Fuel cost @ 30¢/MBtu 14.4 12.9 11.1 Fuel cost @ 60¢/}..1Btu 17.4 15.9 14.1 80%Plant Factor Plants Fuel cost @ 30¢/MBtu 10.1 9.2 8.0 Fuel cost @ 60¢/MBtu 13 .1 12.2 11.0 1,000 313 9.9 12.9 7.3 10.3 4.Gas-Fired Steamplants,Railbelt Area,50%and 80%Load Factor (Public Financing).(Assumed heat rate of 10,000 Btu/kwh) Plant size,MW 100 200 500 Investment cost,$/kw 444 409 334 Unit energy costs including fuels,mills/kwh: 50%Plant Factor Plants Fuels @ 30 cr/MBtu 13 .0 11.7 10.1 Fuels @ 60 (:/rvffi tu 16.0 14.7 13 .1 Fuels @ $l.OO/MBtu 20.0 18.7 17.1 1,000 280 9.1 12.1 16.1 Fuel costs @ 30¢/MBtu Fuel costs @ 60¢/Ivffitu Fuel costs @ $l.OO/MBtu 80%Plant Factor 9.2 8.4 12.2 11.4 16.2 15.4 Plants 7.4 10.4 14.4 6.8 9.8 13 .8 Appendix I G-61 Energy and Power Cost Trends Energy and power economics are undergoing very rapid change,and these changes are extremely important in terms of new decisions on new sources of energy supply.Up until the early 1970 's,most energy planning assumed that abundant,low cost energy supplies would be available on a long term basis from oil,natural gas,and nuclear fuels.Long term trends,especially since about 1950,seemed to support this assumption. The more recent experiences,particularly since the 1973 oil embargo, provide the outlook that energy will be a precious and relatively costly commodity for the foreseeable future.Key changes include the huge increases in fuel prices,added costs for pollution control,very rapid increases in nuclear costs,and absence of any new technological break-through. The studies for the new Alaska Power Survey reflect the start of trends towards much more costly energy supply in Alaska.Generally,these studies reflected data up through mid-1973.Events since that time indicate that most of the cost figures in the power survey are now too low. Fuel prices have continued to escalate rapidly as have costs for labor and materials. The rapid pace of change makes many traditional cost comparisons obsolete.For example,the 1969 Alaska Power Survey and other studies at that time assumed long range generation costs using Alaska natural gas would be on the order of four mills per kilowatthour.Nationwide at that time,it was generally assumed that large nuclear and coal plants would have about the same four mill average generation cost.These figures generally became the yardsticks for measuring feasibility of new power installations. The nuclear and coal-fired steamplants are still the major yardstick for the U .S . ,but is very difficult to put current values on the yardstick because of the rapid cost increase.It now appears that the minimum generation costs for large new baseload thermal plants may be in the range of 15 to 20 mills per kilowatthour for the South"48"states. A recent Interior Department report estimated unit costs of 18.8 and 19.8 mills per kilowatthour for new baseload (70%capacity factor)nuclear and coal fired plants.Y This was premised on 1973 costs and 1,000 MW size plants. 1/Energy Perspectives,USDI,1974.Based on Project Independence studies. Appendix I G-62 - That report indicated unit costs of 30 mills per kilowatthour for nuclear and 28 mills for coal if similar plants were operated at a 40 percent annual capacity factor. In addition to rapidly increasing fuel costs,the investment costs for thermal plants have been increasing very rapidly,partly through inflation and higher rates and partly through added costs for pollution control devices.One publication indicated the following trends y: Dollars per Kilowatt Installed Capacity (Based on 1000 MW plants) Nuclear plants Fossil fired steamplants 1965 119 95 1970 222 178 1974 558 446 1984 850 680 A more recent report by Edison Electric Institute indicated construction costs for coal-fired steamplants ordered in 1974 for 1979 operation would cost $525 per kilowatt.Cost of scrubbers for air pollution control amount to an additional $140-$150 per kilowatt.?:../Smaller plants suitable for use in the Railbelt area would logically cost more. Review of Fuel Costs and Availability It seems certain that by 1985 Alaska's production of oil and natural gas will be a major portion of total U .S.production,and that the bulk of the Alaska production will be for export to the South "48"markets. Some cost advantage should prevail in Alaska because of the high trans- portation costs,however,Alaska fuel costs will certainly reflect broader national and international trends.Policies governing choice of fuels will also reflect the broader national concerns. 1/ 2/ Olds,FC;"Power Plant Capital Costs Going Out of Sight",Power Engineering,August 1974. "Utilities Hedge on Nuclear Plans;Coal Plant Prospect Brightens," Engineering News Record,August 21,1975. Appendix I G-63 At this time,it no longer appears appropriate to assume oil and natural gas will be an available option for major power supplies in the long range where options exist to utilize other sources.If this is true,the conventional nuclear and coal-fired plants will become the most readily available alternative to development of major new hydro sources for the Railbelt. A vail ability of ample supplies of coal for electric generation in the Railbelt area seems assumed as reported in the power survey.In addition to the active mine near Healy,there are active leases in the Beluga area. Development of expanded coal mining is considered very likely in the near future.It is likely that new coal mining would be primarily for export to the South 1148 11 but opening of new mines would probably assure adequate supplies of coal for utilities use in Alaska. Current Alaska coal production is limited to the Usibelli mine near Healy which furnishes coal to the GVEA powerplant at Healy,Fort Wainwright near Fairbanks,and Fairbanks Municipal Utility System in Fairbanks. The power survey stated mine mouth coal delivered to the Healy steamplant was 47¢per million Btu in early 1974.Prices at the end of 1974 were as follows: - GVEA cost at Healy powerplant FMUS cost delivered to Fairbanks Ft.Wainwright cost delivered to Fairbanks Freight cost to Fairbanks Cents Per Million Btu 53 85.6 93.2 32.6 $/ton 8.80 14.21 15.46 5.21 The cost of transportation from Healy to Fairbanks at $5.21 per ton and 8,300 Btu per pound is equivalent to 3.2 mills per kilowatthour based on 10,000 Btu/kwh. The Federal Power Commission recently estimated the value of coal for electric generation at 60¢per million Btu for the Fairbanks area and at 50¢per million Btu for the Anchorage/Kenai /rea;in their determination of power values for the current FPC studies.1:. 1/FPC letter of Aug.12,1975,to Alaska District,Corps of Engineers. Appendix I G-64 - --There is a wide variety of opinion on probable future cost of coal.For many years,coal prices were set a small margine above production costs to compete with low cost oil and natural gas supplies.This pricing situation has changed dramatically in recent years with the changing energy situation.The much higher prices for oil and incentives for converting from oil and gas to coal substantially increases market value of the coal. Nationwide average prices for utility coal have increased dramatically since the early 1970 1s.Average price nationwide increased 57 percent in 1974 (from 51.4 to 80.9 cents per million Btu)according to FPC statistics. The Federal Energy Administration's draft environmental impact statement on "Energy Independence Act and Related Tax Proposals"predicted a long-term price of low-sulfur coal at around $].50/million Btu.This is premised on current price levels (no inflation),and may be too low. According to some,the price of coal will eventually rise to equal the price of oil on a cost per Btu basis,providing transportation costs are accounted for. It seems probable that any major Alaskan coal mining would result in a pricing structure tied to the broader U .S.market,in which case Alaska should have some advantages due to transportation costs. For purposes of this study,it is assumed that 1985 costs without inflation of utility coal for major Railbelt power supplies will be in the range of $1.00 to $1.50 per million Btu. Fuels for conventional nuclear powerplants have also increased substan- tially over the past few years,but remain a comparatively small portion of average costs of nuclear generation. Review of Available Alternatives Coal-fired Steamplants It is assumed that any major new coal-fired plants would be located close to mining operations,probably in the Beluga area for power supplies to the Anchorage-Cook Inlet area,and in the Healy area for power supplies to the Fairbanks-Tanana Valley.Based on relative sizes of power markets, individual plant size would likely be 500 MW or less for the Anchorage- Cook Inlet area and 200 MW or less for the Fairbanks-Tanana Valley area,and individual plants would likely have at least two units.Because of Appendix I G-65 operating characteristics,and maintenance and reliability requirements, it seems unlikely that very large unit sizes (500 MW and up)could be utilized before about the year 2000. The power survey studies included evaluations of likely costs for coal fired steamplants of 200 MW,500 MW,and 1,000 MW capacity.The 200 MW and 500 MW sizes are considered reasonably representative of plant sizes that could be considered as alternatives to Upper Susitna power for the Fairbanks-Tanana Valley and Cook Inlet areas,respectively.Cost estimates for the 200 MW and 500 MW plants were updated for use in the current study,and the results are summarized on Table 16. Appendix I G-66 - .-- Table 16.Alternative Generation Costs for Conventional Coal-fired Steamplants Plant Size,MW 200 500 Number of Units Investment Cost,Railbelt, $/kw Cost of Environmental Equipment $/kw Installed Cost Capital Cost,mills/kwh Operation and Maintenance, mills/kwh 2 526 200 726 14.5 1.6 2 430 200 630 12.6 1.3 Fuel Cost,mills/kwh 10.0 Transmission Cost to Load Center 2.5 Total Energy Cost mills/kwh 28.6 15.0 2.5 33.6 10.0 2.5 26.4 15.0 2.5 31.4 Appendix I TABLE G-16 G-67 The principle assumptions reflected in this update include: 1.Updated investment costs presented in the power survey (January 1973 price levels)to January 1975 prices used the Engineering News Record composite construction cost index.Using the Handy- Whitman steam generation plant cost index,the estimated total energy cost would be slightly higher--approximately 6 percent.The basic estimate reflects South "48"construction costs and an Alaska con- struction factor of 1.8. 2.Increasing the investment cost by $200 per kilowatt to reflect estimated environmental protection costs which were not specifically included in the estimate for the Alaska Power Survey.The data used in the power survey was for plants completed during the 1960's; current practice involves considerable additional expense for control of sulfur,particulates,and nitrogen oxide in stack emission and substantially increased costs for cooling water facilities. 3.Annual capital cost was determined using a 35-year life and an interest rate of 6-5/8 percent.This equals the current (FY 1976) Federal repayment rate for water projects and closely approximates a current composite of municipal and REA borrowing costs.Annual fixed charges of 8.77 percent for public,non-Federal financing were determined (including cost of money,depreciation,interim replacements, insurance and payments in lieu of taxes). 4.Operation and maintenance costs presented in this power survey were updated to July 1975 costs,using the U.S.Department of Labor Cost of Living Index.The power survey estimates reflect an Alaska cost factor of 1.50. 5.Fuel cost range of $1.00 to $1.50 per million Btu and a heat rate of 10,000 Btu per kwh. 6.Annual capacity factor of 50 percent. 7.Transmission costs are on the same basis as costs of transmitting Susitna River hydro project power to the load centers.Smaller voltage lines were assured.Distances from Beluga Lake area to Palmer area and Healy to Ester are both approximately 100 miles. The indicated average unit cost of 26.4 to 31.4 mills per kilowatthour is intended as an assessment of alternative costs for I\ailbelt area power supplies from coal-fired steamplants under current cost levels. ~~~gndiX I - .,- The Federal Power Commission prepared estimates of power values for the Vpper Susitna studies premised on estimates for coal-fired steam- plants for the Fairbanks and Anchorage-Kenai area.Y These estimates incorporate the following assumptions: 1.Interest rates of 5-7/8 percent for Federal financing;and 6.25 percent and 5.95 percent for Anchorage and Fairbanks,respectively,for public,non-Federal financing. 2.A two-unit,150 MW plant for the Fairbanks area with fuel cost of 60¢per million Btu and a heat rate of 12,000 Btu/kwh. 3.A three unit,450 11W plant for the Anchorage-Kenai area with fuel costs of 50¢per million Btu and a heat rate of 9,800 Btu/kwh. 4.The power value estimates incorporate transmission costs to the load center and a credit for the hydro based on higher availability / reliability . The FPC estimates were converted to an average mill rate for comparison with the other alternatives: Fairbanks Coal-fired Alternatives Public,non-Federal financing,29.5 -32.5 mills/kwh. Federal financing (6-1/8%),27.8 -30.6 mills/kwh. Anchorage-Kenai Coal-fired Alternatives Public,non-Federal financing,24.6 -27.3 mills /kwh. Federal financing (6-1/8%),22.3 -24.6 mills/kwh. The above results are quite similar to the estimates based on the power survey.It is recognized that the interest rates used for FPC are somewhat lower than present Federal repayment criteria and that in other respects the two evaluations are somewhat dissimilar. 1/FPC letter dated August 20,1975,to Corps of Engineers . ~~ggnd;x I Diesel-electric Powerplants Several smaller towns will have no alternative but diesel electric generation until they are interconnected to a larger system. Fuel costs remain the major cost for generation by diesel.However,equipment and construction costs have increased significantly since the power survey. Units identical to those costing $160/kw in the power survey cost $220/kw in late 1974 for 1975 delivery.Y Planning,engineering,and financing costs are additional.Heavy duty indoor units in the 2500 kw to 5000 kw size range are costing $300/kw,excluding site,engineering,contingencies, financing costs I and interest during construction.Y The following tabulation shows diesel generation costs using assumptions similar to those incorporated in the power survey studies and the more recent equipment cost data: Plant size I MW Type of Service Heat Rate,Btu/kwh Investment cost $/kw 5.0 Medium duty 10,370 270 5.0 to 10 Heavy Duty 10,000 400 Unit generation cost,including fuel,mills/kwh: Fuel cost @ 30¢/gal 40¢/gal 50¢/gal 60¢/gal 33.3 40.7 48.1 55.5 32.8 40.0 47.1 54.3 Assumptions include two units per plant,longer life and slightly higher efficiency for heavy duty units. Distribution costs and losses are not included. 1/Source:Glacier Highway Electric Association,Juneau,Alaska 2/Source:CVEA/KPU experience Appendix I G-70 - One recent study estimated diesel generation costs at 34.6 mills/kwh in 1974 based on $220/kw basic equipment costs and fuel at 33¢/gallon.1/ Future costs for 1980 and 1985 were estimated at 58.6 and 85.4 mills/kwh assuming escalation of equipment costs at 6%/year and fuel costs at 10%/year. Actual manufacturers'cost estimates received by the same firm for similar generation equipment in July 1974 was $297/kw;considerably higher than the assumed $220/kw. 1/R.W.Beck and Associates,Analysis of Electric System Requirements, City and Borough of Sitka,Alaska,April 1974. Appendix I G-71 Hydro As a part of its work for the June 1967 report,Alaska Natural Resources and the Rampart Project,the Interior Department through the Bureau of Reclamation prepared an extensive inventory of Alaskan hydroelectric resources,including evaluation of potential large hydro projects that might be considered as alternatives to the Rampart proposal. The inventory with minor modification has been published in the 1969 FPC Alaska Power Survey and elsewhere. The inventory studies,the evaluation of the few major hydroelectric potentials of Alaska (i.e.,Rampart,Yukon-Taiya,Susitna,Wood Canyon,and Woodchopper)in the 1967 report,and the earlier basin and project reports of the Bureau of Reclamation are the basis of advancing Upper Susitna as the most logical major hydro development of the Alaska Railbelt at this time. Nuclear There are no authoritative studies of large nuclear plants for the Alaska Railbelt.There is a great deal of controversy on nuclear power --many proponents and many opponents.APA feels that detailed evaluation would demonstrate existing nuclear technology is thoroughly adequate to assure engineering feasibility and safety for nuclear plants in the Alaska Railbelt. However,several factors indicate nuclear power would be less attractive than coal-fired plants for near-future consideration.First is performance data on existing nuclear plants --averaging about 70 percent machine availability nationwide because of down time for maintenance and repair and forced outages.This characteristic will improve over time,but for the present,the nuclear alternatives would probably require substantially larger system reserves. Recent cost data indicates that for the South 1148 11 ,nuclear and coal- fired costs are quite similar,with nuclear requiring a much larger initial investment.Because of higher construction costs,it is probable that nuclear power would be considerably more expensive than coal- fired power in Alaska at least for the foreseeable future. Appendix I G-72 - .,.- Other Alternatives There is a known large physical potential for tidal power development in the Cook Inlet area,but again no detailed studies are available. Tide range is considerably smaller than the better known potentials such as Passamaquoddy. Several different concepts for developing the Cook Inlet tidal potential have been mentioned.These include a plan to drain the Inlet at the Forelands with pumped storage units to equalize output of power; and a two basin scheme which would utilize the Knik and Turnagain Arm.The latter in concept would be tied in with road or rail causeways. Because of the interest in alternative energy sources,there is some merit to preparing a good reconnaissance of this alternative.However, considering the huge size of the work involved,the likely range of important environmental considerations,and inherent difficulty and cost of utilizing the low head available from the tide,tidal power does not constitute a reasonable alternative for determining merits of the Upper Susitna. Similarly,geothermal power could eventually prove to be a very valuable resource for the Railbelt.Geothermal potential is considered high for the Wrangell Mountains and portions of the Alaska Range. Subsurface information is not adequate to define the resources. Existing geothermal technology is basically limited to using the best of the resources --preferably hot dry steam,or superheated water that can be reached at fairly shallow depth.As yet,there are no firm indi.cations that large geothermal resources exist in Alaska that could be developed with available technology.On this basis,geothermal power cannot be considered a viable alternative at this time to major coal and hydro power. Wind power is receiving great interest,but existing and likely near future technology is limited to small and relatively costly units. Like geothermal,the long range potential may prove very important, but wind is not a viable alternative for major new power supplies at this time. Appendix I G-73 Part VII FINANCIAL ANALYSIS - This section presents estimates of the market for project power and evaluations of power rates needed to repay the investment in power facilities. The Upper Susitna Project is primarily for power,though present indications are that minor portions of project costs would be allocated to other purposes,such as recreation.Preliminary estimates are that such cost allocations to other purposes would be less than one percent of the total project investment.Thus financial viability of the project becomes the essential element in demonstrating feasibility of the power development.The size of market,amount of investment,and applicable interest rate are the main factors influencing rates for power. Operation,maintenance and replacement costs are a minor part of total annual costs,so they do not influence power rates significantly. If rates needed to repay the hydro development are attractive in comparison to other alternatives that may be available,the project may be considered financially feasible. Present Federal criteria for power producing facilities call for repayment of project costs with interest within 50 years after the unit becomes revenue producing.The applicable interest rate for Fiscal Year 1976 is 6-5/8 percent. Market for Project Power Previous sections presented estimates of power requirements for the interconnected Railbelt system under a range of assumptions for future development.The portion of this power market that would represent demands for project power would depend on rates of growth,changes in operating modes of other facilities,fuel policies,availability and prices.and other factors. At the time Susitna power becomes available.the Railbelt power systems will have several hundred megawatts of capacity in oil and natural gas fired (turbine) equipment.It is assumed that because of fuel cost and other incentives. it will be desirable to place much of the gas turbine equipment in cold reserve.except for limited operation in the peak shaving mode.This is particularly true of any oil-fired equipment and the least efficient of the gas turbine equipment. Appendix I G-74 - .- By 1985.some of the older steam-fired plants ,vould be at or near the end of useful life and likely candidates for early retirement. Under these conditions,it is assumed that firm demands for Susitna power would develop very rapidly. For purposes of these preliminary rate determinations,it is assumed that the firm market for Susitna power would be up to 75 percent of the total utili ty requirements for the mid-range load estiroates for the Anchorage-Cook Inlet and Fairbanks-Tanana Valley area.This is conservative to the extent that it does not assume any demands from the national defense or industrial load sectors.It could be optimistic if the utili ties continue very heavy reliance on oil and natural gas. Table 17 shows the 75 percent assumption in comparison wi th total area load estimates.As indicated on the table,75 percent of utility requirements is equivalent to 61 to 66 percent of total area requirements during the 1985-1995 period. It is recognized that these are oversimplified market assumptions, and that the market estimates will require continued l'efinement as project plans and design are prepared.If it should develop that future demands for project power are somewhat lower.it is reasonable to assume that the project would be staged over a somewhat longer period of time. Assumptions for secondary energy s ales are as follows: 1.With Devil Canyon operating alene,there is relatively little flexibility for scheduling secondary energy so the market for such energy would be limited.The Corps operation studies indicate average annual secondary energy capability of 201 1\41\7.It is assumed that the marketable portion would be 10 MW in the first year of operation (equivalent to 86 million kilowatthours at the market), and that this market would expand in 101M increments to 50 MW in th e fifth year of op era tion . This assumes that the secondary energy could be offered in sizable blocks with guaranteed duration of two to six months,depending on forecasts of reservoir operations,but that relatively little of this energy would be available during mid-winter. Appendix I G-75 Table 17.Assumed Market for Upper Susitna Power Potential market for new hydroelectric power and energy (based on 75%of estimated mid-range utility requirements) Annual Peaking Requirements Annual Energy Requirements 1000 kw Million kwh Year Anchorage Fairbanks Total Anchorage Fairbanks Total 1985 630 160 790 2,760 690 3,450 1986 680 170 850 2,950 740 3,690 1987 720 180 900 3,165 790 3,955 1988 770 190 960 3,395 840 4,235 1989 830 200 1,030 3,640 900 4,540 1990 890 220 1,no 3,900 960 4,860 1991 940 230 1,170 4,140 1,010 5,150 1992 1,000 240 1,240 4,400 1,070 5,470 1993 1,060 260 1,320 4,670 1,130 5,800 1994 1,130 270 1,400 4,950 1,200 6,150 1995 1,200 290 1,490 5,250 1,260 6,510 Year 1985 1990 1995 Comparison With Total Area Power Requirements Anchorage &Fairbanks Assumed Market for requirements new (Mid-range Estimates)Hydroelectric Power Peak Annual Energy Peak Annual Energy 1000 kw Million kwh 1000 kw Million kwh 1,220 5,560 790 1/ 3,450 (65)(62)Y 1,670 7,620 1,no 1/ 4,860 (66)(62)Y 2,300 10,680 1,490 1/ 6,510 (65)(61)Y 1/Percent of total area requirements. Appendix I TABLE G-17 G-76 - -- 2.With the multiple reservoir systems,it is assumed that mClrket fle~dbility could be substantially enhanced and that marketing policies would be premised on maxin'izing annual energy production. In practice,this would likely be achieved by setting firm energy contracts close to average annual energy capability with exchanges and off-peak purchases a.nd to meet contract commitments during low runoff years. The Corps operation studies indicate average annual secondary capability ranging from 40 to 108 :MW for the multiple reservcir system.For purposes of the rate studies,it is assumed the full amount of the secondary energy could be marketed starting in 1990.The Corps values for secondary power were converted to annual energy and transmission losses were deducted to derive the amounts of secondary energy sales used in the rate studies: 6System#1 -690 x 10 kwh/year sales. 6System#2 -932 y,10 kwh/year sales. 6System#3 -345 x 10 kwh/year sales. 6System#4 -630 x 10 kwh/year sales. 6System#5 -690 x 10 kwh/year sales. 3.A rate of 10 mills per kilowatthour is assumed for secondary sales. S coping Analysis AP A prepared a set of estimates of average power rates needed to repay costs of the alternative hydro development plans.This provided a basis for looking at the alternative plans from the viewpoint of impact on power rates.These studies were preroised on prelin:inary designs and estimates prepared by the Corps of Engineers (dams and powerplants) and AP A (transmission systems and operation and maintenance)as reported in the Septerrlber 1975 draft reports of the tv.'o agencies. These preliminary rate estimates are summarized in Table 18 and the cost assumptions incorporated in them are summarized in Table 19. Note that there have been substantial changes in the cost estimates since the Septemb er draft report as dicusssed later. Appendix I G-77 Table 18.Average Rates for Repayment for Alternative Development Plans U - System Plan A verage Rates for Firm Energy (Mills/kwh) System #1 Devil Canyon (W.S.1450),1985 Denali (W.S.2535),1990 24.5 I-A Devil Canyon and Denali both on line,1985 (USBR plan;Corps costs).21.9 1-B Same,but USBR-APA costs,Denali 20.7 System #2 Devil Canyon (W.S.1450),1985 Watana (W.S.2050),1990 21.4 2-A Watana,1985 Devil Canyon,1990 (Revise order of construction)21.0 System #3 Devil Canyon (1450),1985 Watana (2050),1990 Denali (2535),1995 20.9 System #4 Devil Canyon (1450),1985 Denali (2535),1990 Vee (2300),1995 Watana (1900),2000 24.2 4-A Devil Canyon &Denali both on line,1985 Vee 1990 Watana,1995 (USBR plan;Corps costs).22.8 System #5 Watana (2200),1986 Devil Canyon (1450),1990 19.7 y Preliminary scoping analysis for September 1975 draft report; does not reflect cost changes since that time. Appendix I TABLE G-18 G-78 - Table 19.1/Cost Summary for Alternative Systems System #I Unit w.S.Elev. Canpletion Date Dev i I Canyon (1450) 1985 Costs -$1,000 Dena Ii (2535) 1990 Total System Power Production Facilities Construction Costs Interest During Construction Investment Cost Transmission Facilities Construction Costs Interest During Construction Investment Cost Total System Investment Cost Annual Operation and Maintenance Annual Replacement Annual OM &R 389,000 64,430 453,430 114,100 II ,340 125,440 231,400 45,990 277 ,390 730,820 125,440 856,260 I ,538 177 I ,715 - Y Costs are for preliminary scoping analyses in September 1975 draft report and do not reflect revisions since that time. Appendix I TABLE G-19 G-79 Table 19.Cost Summary for Alternative Systems 1/ (Continued) System #2 - Unit W.S.Elev. Completion Date Dev i I Canyon (1450) 1985 Cos ts -$I ,000 Watana (2050) 1990 Total System Power Production Facilities Construction Costs Interest During Construction Investment Cost Transmission Facilities Construction Costs Interest During Construction Investment Cost Total System Investment Cost Annual Operation and Maintenance Annual Replacement Annual OM &.R 389,000 64,430 453,430 184,310 18,320 202,630 600,000 119,250 719,250 18,540 1,840 20,380 I ,172,680 223,010 1,395,690 1,883 396 2,279 Y Costs are for preliminary scoping analyses in September 1975 draft report and do not reflect revisions since that time. Appendix I G-80 - - Tab Ie 19.Cost of Summary for Alternative (Continued) System #3 1/Systems Unit w.S.Elev. Completion Date Devi I Canyon (1450) 1985 Watana (2050) 1990 Dena Ii (2535) 1995 Total System Costs -$1,000 Power Production Fad lities Construction Costs Interest During Construction Investment Cost Transmission Facilities Construction Costs Interest During Construction Investment Cost Total System Investment Cost 389,000 64,430 453,430 184,310 18,320 202,630 600,000 119,250 719,250 18,540 1,840 20,380 231,400 45,990 277,390 1,450,070 223,010 1,673,080 Annual Operation and Maintenance Annual Replacement Annual OM &R !I Costs are for preliminary scoping analyses in September 1975 draft report and do not reflect revisions since that time. I ,883 396 2,279 AppendiX I G-81 Table 19.Cost Summary for Alternative Systems 1/ (Continued) System #4 Devi I Total Unit Canyon Watana Dena Ii Vee System W.S.Elev.(1450)(1905)(2535)(2300) Completion Date 1985 2000 1990 1995 Cos ts -$1,000 Power Production Facilities Construction Costs Interest During Construction Investment Cost Transmission Facilities 389,000 486,400 26 •670 583,070 231,480 45,990 277 ,390 399,000 19,300 478,300 1,792,190 Construction Costs I nteres t Dur i ng Construction Investment Cost Total System Investment Cost Annual Operation and Maintenance Annual Replacement Annual OM &R 184,310 18,320 202,630 7,930 790 8,720 29,130 2,890 32,020 243,370 2,035,560 2,269 2J~* Y Costs are for preliminary scoping analyses in September 1975 draft report and do not reflect revisions since that time. Appendix I G-82 Table 19. 1/Cost Summary for Alternative Systems (Continued) System #5 Unit W.S.Elev. Completion Date Devil Canyon (1450) 1990 Costs -$1,000 Watana (2050) 1986 Total System Power Production Facilities Construction Costs Interest During Construction Investment Cost Transmission Facilities Construction Costs Interest During Construction Investment Cost Total System Investment Cost 403,000 67,000 470,000 6,000 6,000 737,000 146,000 883,000 197,000 20,000 217,000 1,353,000 223,000 1,576,000 Annual Operation and Maintenance Annual Replacement Annual OM &R 1,883 396 2,279 !I Costs are for preliminary scoping analyses in September 1975 draft report and do not reflect revisions since that time. Appendix I G-83 The method used involves calculating 1985 present worth values of investment and OM&R costs and energy sales and reducing both to equivalent annual values.Revenues from secondary energy 00 mills per kilowatthour)are deducted from equivalent annual cosLe;..An average rate for firm energy to recover the remaining costs is then computed. In each case,the repayment period covers 50 years after each unit becomes revenue producing under the market assumption presented earlier,the full firm energy capability of each unit could be marketed in the first year after completion.The rate determination also incorporates the market assumptions for secondary energy which were presented previously. Table 21 summarizes the average rates for firm energy for the four systems and also illustrates effect on rates of alternate assumptions of scheduling project units. The highest indicated rate is for System #1 (24.5 mills per kilowatthour). This reflects the very limited energy capability of a Devil Canyon Project for the first five years without upstream storage.System 1- A (2].9 mills)assumes the same design and costs,but completion of both Devil Canyon and Denali in 1985 as proposed in the USBR-APA plan.The indication is that if Devil Canyon operates for a significant time period without upstream storage.power rates would be significantly increased. Power rates are of course very sensitive to design assumptions. The USBR estimates for Denali Dam were prepared on a very conservative design reflecting the foundation conditions at that site.This is discussed in the May 1974 Status Report.A rough update of the USBR costs to January 1975 price was made.This indicates the new Corps estimates for Denali are approximately 20 percent higher than would be derived from the Bureau estimates.SystelT'1--B,(20.7 mills)using USER costs updated to January 1975,indicates the added conservatism in the Corps estimate adds about 1.2 mills to the average rate. System 2-A assumes Corps design and costs but reverses the order of construction.(Watana on line in 1985 and Devil Canyon on line in 1990.)This indicates a small reduction in average rate,again related to the limited storage capacity at Devil Canyon. System 4-A a.ssumes Corps design and costs completion of Devil Canyon and Denali in 1985,with Vee and Watana following at five-year intervals. Appendix I G-84 ,- If USER design assumptions were used for Denali,the rates for System #3,#4,and #4-A would be somewhat lower than shown on the table. System #5 has the lowest indicated rate (19.7 mills per kilowatthour), or approximately 5 percent lower than System #l-B,#2-A,and #3. The general conclusions from the preliminary analysis includes: 1.There appears to be several alternative development plans for the Upper Susitna that would yield approximately equivalent power l"ates to the consumer,and that on the basis of the power rates there is little preference as between plans. 2.The iIrportance of upstrearr.storage above Devil Canyon is evident. 3.ThE:'studies indicate merit to the Denali unit as a possible future addition. Comparison with May 1974 Status Repor~ APA's May,1974,Devil Canyon Status Report provides a basis for comparing recent cost changes.The development plan presented in the Status report is analogous to the Corps System #1,except that AP A assumed con:pletion of both the Devil Canyon and Denali units at the same time while the Corps System #1 assumes Denali would be completed five years after Devil Canyon. The ~tatus Report used January 1974 price levels and the applicable interest rates for FY 1974 which was 5-5/8 percent for repayment. The present studies are premised on the FY 1976 interest rate of 6- 5/8 percent and January ]975 price levels. The year ending January ]975 had very high rates of inflation in all segments of the economy.The Bureau of Reclamation's composite construction cost index increased 21 percent for the period. The change in interest rates without any inflation would increase annual repayment requirements by about 18 percent.The combination of higher costs and higher interest rates represents approximately a 42 percent increase in annual costs as indicated on Table 20. Appendix I G-85 Table 20.Comparison with May 1974 Status Report Status Report Plan (Devil Canyon +Denali) Price Level Applicable interest rate for repayment Estimated construction cost,$millions Interest during construction $millions Investment cost $millions Annual payment,excluding OM &R ,$millions Appendix I TABLE G-20 G-86 Costs as in May 1974 Status Report January 1974 5-5/8% 597.1 84.9 682 41.0 Current Studies January 1975 6-5/8% 724 121 845 58.1 Increase +21% +42% - Revised Cost Estimates During the review process,there were some significant changes in cost assumptions for the various alternative development plans.From the viewpoint of the power market,the changes all favored System #5-- that is relative cost increases for System #5 were substantially smaller than for the other alternatives under consideration. A preliminary check was made using the new costs which indicated the following average rates for the various systems:(same system designation as Table 18) System #5 -20.4 mills/kwh System #2A -22.3 mills/kwh System #2 -23.0 mills /kwh System #IB -23.0 mills/kwh System #3 -23.3 mills/kwh Again the range is relatively small,but under the latest cost assumptions, System #5 would have about 10 percent lower power rates than the next most favorable plan. Average Rate Determination for Proposed Plan Table 21 summarizes the estimate of average rate for firm energy needed to repay investment in the project facilities.The methods used are the same as for the scoping analysis.The indicated average rate is 21.1 mills per kilowatthour. Note that the scoping analyses discussed previously found a 20.4 mill average rate for System #5.The difference of 0.7 mills reflects added transmission costs adopted for the proposed plan (substation in Talkeetna vicinity,switchyard near Healy,and tVI/O single circuit lines in lieu of the double circuit assumptions used in the scoping analyses). The indicated n.te for the proposed plan is significantly lower than the estimated costs of power from coal-fired steamplants.The analysis does not reflect allowance for future inflation.A rough estimate indicates that with a five percent per year cost escalation and construction schedules as contemplated in the Corps proposaL required rates for the system would exceed 40 mills per kilowatthour. Appendix I G-87 Table21.AverageRateDetermination-System#5(Watana+DevilCanyon)ProjectCosts,$10001986PWCostsProjectEnergySales,WillionKwhG"")--l::t:>Revenue$1,000I::t:>-o,coOJ-OProducingFirmSecondary1986PW1986PWcorrolT1:::::lYearInvestmentOM&RInvestmentOM&REnergyEnergyFirmEnergySecondaryEnergyc..G"")......IXN86(1986to1989)81---'......19861,278,81018291,278,81030541987""17210,4311511988"II2582131989"II3442661990489,2402400378,52048606903,527(1990to2040)1991"5150II3,5057,7321992"5470"3,4911993"5800"3,4721994"6058"(1994to2040)51,8732040--Totals1,657,33076,2998,443AnnualorAnnualEquivalent113,3452,2675,218577AverageRateComputation:(1)AnnualCosts:(2)(3)(4)(5)Capital$113,345,000OM&R2,267,000Total$115,612,000Revenuefromsecondaryenergy@10mills/kwh-5,770,000Requiredrevenuefrom:firn1energysales$109,842,000Equivalentannual:firmenergysales5,218,000,000kwhAveragerateforrepayment109,842,000/5,218,000,000=21.1mills/kwh~t -Power Marketing Considerations The average rate is useful mainly as a.basis for easy comparison of the proposal and the alternatives.Actual rr.arketing contracts would likely include separate provisions for demand and energy charges and account for wheeling charges,reserve agreements,and other factors. There are some built in inequities for any given method of pricing.Most utility systelT's and most large Federal systems use essentially a postage stamp rate,that is power rates set the same for all delivery points on the system.Actual costs of serving the loads vary with the distance and size and characteristics of load--it is more costly to serve a small load several miles from the power source than to serve a larger load nearby. Policies vary from system to system as to portions of "hookup"costs born by the customers. Actual ratES for the Susitna system might reflect several items of costs and revenues not identified in the project studies.For example,it is likely that considerable use of project facilities would be made over the life of the project to wheel power from other sources.Any wheeling revenues would lower overall project power rates somewhat.Conversely wheeling costs for project power delivered over non-Federal transmission lines would need to be worked into project rate schedules.This is now done under APA marketing contracts for the Snettisham Project;there are many similar situations in other Federal power systems. Rough estimates were made on a cost-of-service basis for power deli vered at Fairbanks and at Point :MacKenzie under the proposed plan.These indicated that about 85 percent of the project costs (or about 17.9 of the 21.1 mills per kilowatthour average rate)is involved in producing the power (Devil Canyon and Watana units and the transmission line between De"'il Canyon and Watana).The remaining 15 percent is for transmission facili ties to the major load centers.If the transmission costs were charged to power delivered at the two load centers on a cost of ser"'ice basis,average rates would be about 25.2 mills per kilowatthour at Fairbanks and 20.2 mills at Point ~'facKenzie.The difference relates to distance and size of load. As stated elsewhere,the transmission plan to deliver project power in Anchorage would need to be worked out in the detailed post authorization studies.It would involve added costs,either through wheeling charges for project power over non-Federal lines or project transmission lines around or under Knik Arm.These costs could be about the same for alternative power sources such as the Beluga coals. It is considered essential that scheduling of project facili ties be closely tied to the marketing function. Appendix I G-89 Market Aspects of Other Transmission Alternatives It is reasonable to expect modifications of the project transmission system to meet changing requirements through time.The capacity of the main 345 kv and 230 kv lines could be upgraded substantially as needs arise by adding compensation and transformer capacity.Additional substations could be provided as warranted by future loads and subject to 3.case by case determination of economics.Similarly,extensions of the project transmission lines to serve other areas would be considered on the basis of needs,and economics,and available alternatives. Anchorage-Cook Inlet Area The costs in the proposed plan are premised on delivery points to sub- stations near Talkeetna and Point MacKenzie.Hough estimates indicate similar costs for a plan with delivery points at Talkeetna,Point MacKenzie, and the existing APA Palmer substation.Thus,basically the project costs can provide delivery points on the existing CEA and APA systems north of Knik Arm,but do not include costs of delivering the power across or around the Arm. With or without the Susitna Project,additional transmission capability is needed on the approaches to Anchorage.The CEA plan of Knik Arm loop at 230 kv is an important step in developing this capability,but additional capacity would be needed by the mid-1980's.Essentially the same problems would exist with alternative power sources such as the Beluga coals,so in this sense the solution doesn't bear on the merits of the Upper Susitna Project. Detailed studies following project authorization would need to consider the several alternatives for providing power across Knik Arm.Costs would be worked into rate structures either through wheeling charges on non-Federal lines or project lines if needed. Glennallen and Other Points on the Richardson Highway Rough estimates were made for transmission systems to deliver project power to the CVEA system at Glennallen.Line distance from Palmer is approximately 136 miles. The studies consisted of rough cost estimates for alternative 138 kv and 230 kv lines and comparison with load data presented previously.They indicated that on the basis of normal utility requirements,an intertie to Glennallen could probably not be justified until after 1990,then a line to Glennallen is included in the plans and costs for the initial development proposal. Appendix I G-90 - - Over the long term,it appears that a transmission loop from Palmer to Glennallen and then north along the Fichardson Highway to interconnect with the CVEA system should receive further consideration. Appendix 1 G-91 EXHIBIT G-l PARTIAL BIBLIOGRAPHY OF RELATED STUDIES Appendix A Partial Bibliography of Related Studies 1.Advisory Committee Reports for Federal Power Commission Alaska Power Survey: Report of the Executive Advisory Committee,December 1974 Economic Analysis and Load Projections,May 1974 Resources and Electric Power Generation,May 1974 Coordinated Systems Development and Interconnection,December 1974 Environmental Considerations and Consumer Affairs,May 1974 (FPC has its summary report in preparation) 2.Alaska Power Survey,Federal Power Commission,1969. 3.Devil Canyon Status Report,Alaska Power Administration, May 1974. 4.Devil Canyon Project -Alaska,Report of the Commissioner of Reclamation,March 1961,and supporting reports.Reprint,March 1974. 5.Reassessment Report on Upper Susitna River Hydroelectric Development for the State of Alaska,Henry J.Kaiser Company,Sept.1974. 6.Project Independence,Federal Energy Administration,1974.A main report,summary,seven task force reports and the draft environ- mental impact statement. 7.Engineering and Economic Studies for the City of Anchorage,Alaska Municipal Light and Power Department,R.W.Beck and Associates and Ralph R.Stefano and Associates,August 1970. 8.Power Supply,Golden Valley Electric Association,Inc.,Fairbanks. Alaska,Stanley Consultants,1970. 9.Copper Valley Electric Association,Inc.-15 year Power Cost Study, Hydro/Diesel,Robert W.Retherford Associates,October 1974. 10.Environmental Analysis for Proposed Additions to Chugach Electric Association,Inc.,Generating Station at Beluga.Alaska,Chugach Electric Association,October 1973. Appendix I EXHIBIT G-l 11.Central Alaska Power Pool,working paper,Alaska Power Administration, October 1969. 12.Alaska Railbelt Transmission System,working paper,Alaska Power Adminis tration,Decemb er 1967. 13.Electric Generation and Transmission Intertie System for Interior and Southcentral Alaska,CH2M Hill,1972. 14.Central Alaska Power Study,The Ralph M.Parsons Company,undated. 15.Alaska Power Feasibility Study,The Ralph M.Parsons Company,1962. - - EXHIBIT G-2 UPPER SUSITNA RIVER HYDROELECTRIC STUDIES REPORT ON OPERATION,MAINTENANCE, AND REPLACEMENTS .- Contents Title Introduction and Summary Operation Assumptions Marketing and Administration Ann ual Cos ts Replacemen ts Tables 1.Alternative System Plans -Installed Capacity &Firm Energy.. . Page No. G-l G-3 G-4 G-4 G-5 G-2 2. 3. 4. Itemized 0 &M Cost Estimate Annual 0 &M Cost Summary Annual Replacement Costs . . Figures G-7 G-ll G-12 1.Upper Susitna Basin Location Map i G-13 Appendix I Exhibit G-2 Introduction and Summary This paper presents estimates of the annual recurring costs for project operations and maintenance,power marketing,and replacements for the Upper Susitna hydroelectric projects. Figure 1 shows general locations of the potential units of the Upper Susitna project in relationship to the Alaska Railbelt.The four key Upper Susitna damsites are Devil Canyon,Watana,Vee,and Denali. Separate estimates were prepared for each of five alternative development plans or systems.The five alternatives are identified on Table 1 along with power and energy capability for each systerr. The Corps of Engineers proposes an initial development consisting of the Devil Canyon and Watana sites (System #5).The high Watana dam plan is proposed to be constructed first followed by the Devil Canyon unit. The estimates reflect .A2A's assumed operation plan for the project power- plants,reservoirs,and transIT'ission lines.as well as estimated costs for pewer marketing and overall project adminish·ation. Summary of Op eration,Maintenance,and P.eplacement Cos ts Annual Operation .Annual Total and Maintenance Replacement OM&R $1,000 $1,000 $1,000 System #1 -Devil Canyon and Denali 1,538 Sys tern #2 -Devil Canyon and Watana 1,833 System #3 -Devil Canyon, Watana &Denali 1,833 System #4 -Devil Canyon, Watana,Denali,&Vee 2,269 System #5 -Devil Canyon &Watana (proposed plan)1,833 G-I 199 453 453 618 517 1,737 2,286 2,286 2,887 2,340 Table1.~_tCn:12.tivf::..Syst:-nlPlam;Y..~II-'.-'..,-..',..,g.F'~-E~:~:~~..~~~~"i,'__.~_-:~.E.~:~~:.L-._".....::nl.r,,__~.et:gy.?()1...DevilIJciY.C,~~..,_~,~._.~:_:~~~Y'~.r.:"__~Instc)II~dFirrn>,8t,l<::dFi~'mCar)itcityJ<nJ·~·~;-C~,apaCjty1000Mi.lhc·.!000kwkwhkwJ.,,,'•...wdEnE.r·~!y\'·1ililor,(...."';j....!.,~-tf''''~.{~"'"l:-t'crgyZ-~~)1jlor",'5')stet~)'fetalkw-(:!J2~r.ili'r0001.s1r-"T,;.Uf;"1F":},;'l:Scc:~,rltj3:~)"kwh;';ergy"{',1'·'Yll,J,.110~~,f;CW",y3.fj:____..'.n._.·.__.~..~.~._~~·,Inst.alJ~dFn':TkwhEnergM'illinr'·Cap;lc"ity1000kwW.S.e'M.SrSYstem<'"""....::..~._._~~~System!:l.DevilCanyon1450Denali2535System#2DevilCanyon1450Watana2050..)INSystem#3Devil'Canyon1450Watana2050Denali2535System#4DevilCanyon1450Den.ali2535Vee2300Watana1905System#5Watana2200DevilCanyon14501985199019851990580'.,.6002497262847020595802497701Notes:System#5istheproposedinitialdevelopmentplan.DataisfromCorpsofEngineersstudies.)~ -- Operation Assumptions For purposes of this study,it is assumed the project headquarters and main operations center would be near Talkeetna or at some other equally accessible point on the system.It is recognized the remote operations center is not dependent on being adjacent to a powerplant. This central project headquarters,would house the remote powerplant opera.tion and dispatch center.Powerplant operation and dam and re- servoir operations would be from this operation-dispatch center for each plan.Electricia.n/operators and mechanic/operators would be located at the powerplants to provide for routine maintenance and manual operation when required.Denali dam would be remote controlled,with a caretaker in residence at the damsite.Specialized personnel such as electronic technicians,and meter and relay repairmen would serve at the several powerplants and substations,but would work out of project headquarters. Project administration,including supervision of power production,water scheduling,and transmission facilities,would be from project head- quarters. Major turbine and generator inspection and maintenance work would be accomplished by electricians,mechanics,engineers,other experienced APA personnel,and manufacturers I representatives as required. Alaska Power Administration's main office would handle power marketing, accounting,personnel management,and general administrative matters. Transmission line maintenance would be handled by two linecrews with integration of the Eklutna Project linecrew.Transmission line mainte- nance warehouses and parts storage yard would be located at Devil Canyon or Watana.approximately midway betvveen Devil Canyon and Fairbanks,and at project headquarters.Members of the linecrew would be stationed along the line.transmission maintenance stations,and the major sub- stations to provide routine line patrol and minor caretaking tasks and security around the facilities.For major maintenance work,the trans- mission line crew members would gather at the problem area. Visitor facilities with provisions for self-guided tours through the powerplant would require only occasional assistance from operation personnel. Project related recreational facilities would involve cooperation between Federal,State,and local interests and likely be maintained by a State or local entity. G-3 Project operation,maintenance and administration would likely include the e:>.'isting Eklutna Project,with a resulting net savings to the electrical consumer.Eklutna would be supervisory controlled from the rr:ain operations center with electricians/operators and mechanic/operators stationed at Eklutna.It is estimated that approximately $100,000 per year could be saved by joint operation of the Eklutna and Susitna Projects. Marketing and Administration The marketing and adrrinistration aspects involve three main functions: 1.Administration Personnel management Property management Budgeting Marketing policy Rate and repayment studies 2.Accounting CustoI!'er billing Collecting Accounts payable Financial records Payroll 3.Marketing Rate schedules Power sales contracts Operating agreements System reliability and coordination Part of this work would be carried out by the project headquarters; overall administration and support services would be handled by the APA headquarters staff. Ann ual Cos ts The estimated costs for operation,maintenance,marketing,and admin- istration are based on itemized estimates of personnel,equipment,supplies, and services required to accomplish the work. G-4 - - Operation and maintenance requirements for Systems #2,#3,and #5 would be substantially the same.Each of the three plans has powerplants at Devil Canyon and Watana that are similar except for installed capacity (10701',1W for System #2,1370 MW for System #3,15681vlW for System #5). Number of units and powerplant layout is the same for the three plans, so staffing would be essentially the same for each plan.System #3 includes Denali Dam,but added O&M costs for the structure would be minor.For purposes of this study,annual operation and maintenance costs are assumed the same for the three plans. The estimate assumes Federally classified personnel providing management and administrative functions and wage grade personnel doing the physical day-to-day technical operation and maintenance of the project.Wage rates for the classified employees are based on the middle rate within a grade. Wage grade personnel rates are based on prevailing wages in effect in the Anchorage area and reflect basic hourly rates,benefits,and overtime provisions. Costs of supplies,equipment and personnel requirements are based on Bureau of Reclamation Guidelines,characteristics of equipment,and Alaska Power Administration operating experience on the Eklutna and Snettisharn Projects in Alaska.The Eklutna project is a fully staffed facility,induding a transmission linecrew,which has been operated by APA and its predecessor agency since project construction in 1955.The Snettisham Project is an isolated project,sepa.rated from Juneau load center by 45 miles of rugged terrain and water.A maintenance crew performs routine maintenance at the project site,while proje.ct opera- tions are remotely controlled from Juneau.It is envisioned that the Upper Susitna River Basin Project would have some characteristics of both projects . Itemized costs for operation,maintenance,marketing,and admi.nistration for the alternative plans of development arc present in Table 2. Costs by major category and number of pel'sonne!are summarized on Table 3. Replacements The annual replacement cost provision establishes a fund to finance major items which have a life period of less than fifty years for project repayment.The objective is to cover costs and insure financing for a timely replacement of major cost items to keep the project opera- ting efficiently throughout its entire life. G-5 items cc.','c'ced in ch.de generato:r windings,communication equiprcent,a '.i!·;,:<l perc",';}';'c,f the tra:nsmisslon towers.and several items in the sub-· s ;a'4 <'H\c:.r,"I:vi i;,:;hva:r';:},3.Items covpred by routine annl;al maintenance ce,",'<r:'~'tlGt:::overcd by the replacement fund include vehicles,smail 0':'1:>.;3,camp u~jli ties,and materials and supplies.Major features ::.,".,'..h:'\l;3 ;::.r;c·'povel--p1ant structures are considered to hc1ve service ::\[':5 le',gel:'tha:n '-he 50-year project repayment period and their costs are :>i c..:'l''I:'U:\:.hf:n.placernent funds, The "''''''U~i'replac,.::n:ent cost is based on experienced d<~.ta by the Bureau c'£~.I.:n:).;'WI.,.Trj c'procedure and basic factors have been adopted by the Departr;'icat of Interior.The factors developed provide a sinking fund Lr t1,t'V:,l,Aio',.J,Si t.:::T\S so that by the end of the items I service life,the r,y,';'""ill l·(·':':'g';:,er,.:"iJgh to replace it.The san;e interest rate c.sed fa, pYo>!"<';"~YT1i,~,·,t i~q usee to establisb tne sinking fund.The Fiscal '(,",:)',ie-I.e rA 6·')5 percent was established by the Dep,irtment of tb (~".L f'~.2.S t~~r\l 'I"tl"f~j"''''::3 [.;.~pr)tu ·~.hF:C:'1t.re ?owerplant)substation,and switch·yarc~. '1;-]ii;Yt )c,.;ih;.'~>:'2,,:lsmission towers,fixtures and conductors on Lhe tr;lJ.,c;","s,::;cn ?'{:3~'::'DI,Fight-of-way and clearing costs are not included. Tab}.'":1 presents the annual replacement factors based on 6-5/8 percent intei·~::t rate.the costs of the pertinent project feature,and the annual l'l'placement lured for the altel"native plans of development.The project cos1;:,are on a.:anUal"y }975 basis.Powerplant costs are from Corps ,-,[Ehgin-::el cstirn.ates wbiJe Alaska Power Administration estimated the transmission,SU.;)station ,and switchyard costs. G-6 - -TABLE 2.ITEMIZED OPERATING &MAINTENANCE COST ESTIMATE SYSTEM 1.DEVIL CANYON AND DENALI Devil Canyon Denali Personnel 600 MW No Power 100 MW Future,5 units Supervisory &Classified Project Manager Assistant Project Manager Electrical Engineer Mechanical Engineer Supply &Property Administrative Assistant Secretary GS-14 GS-13 GS-12 GS-12 GS-9 GS-7 GS-5 $30,000 24,700 22,200 22,200 14,500 12,000 9.600 Total Supervisory &Classified Wages Wage Grade 135,200 Electricians Mechanics Heavy Duty Equip.Operator Maintenance Man Meter Relay Mechanic Electronic Technician Powerp1ant Operators Ass't.Powerp1ant Operators Total Wage Grade Wages Line Crew 2 @ 13.00 hr.54,080 2 @ 13.00 "54,080 1 @ 13.00 27,040 2 @ 11.00 45,760 1 @ 13.00 27,040 1 @ 13.00 27,040 6 @ 13.00 162,240 4 @ 11.00 91,520 488,800 Foremen Linemen Equipment Groundmen Operators 2 @ 4 @ 2 @ 4 @ 15.00 13.00 13.00 13.00 hr. " " " 62,400 108,160 54,080 108.160 Total Line Crew Wages C.0.L.A.--25% Shift Differential Sunday Pay Overtime Government Contributions Longevity N.A. Total Fringe Benefits for Personnel TOTAL PERSONNEL COST G-7 332,800 33,800 15,000 8,000 25,000 86,100 167,900 $1,124,700 TABLE 2.(Continued)--ITEMIZED OPERATION &MAINTENANCE COST ESTIMATE_ SYSTEM l--(Continued)--DEVIL CANYON AND DENALI Miscellaneous Telephone Official travel Vacation travel Supplies,Services &Maintenance--Powerplant Supplies &Services--Vehicles &Equipment Employee training Line spray Government camp maintenance Total Miscellaneous $8,000 15,000 15,000 100,000 40,000 5,000 20,000 15,000 218,000 Equipment Operation &Maintenance, D-8 -(1) 980 -(1) Maintainer -(1) Pickups -(4)&(6) Sedan -(1) Lowboy -(1) Dumptruck -(1) Flatbed -(4)&(2) Firetruck -(1) Sno tracs -(2) Backhoe -(1) Crane,50 ton -(1) Hydraulic Crane,20 ton -(1) Line trucks -(4) Total Equipment,etc. Annual Replacement 1.C."'~S.L."'~ $90,000 10 50,000 10 50,000 10 36,000 7 4,000 7 45,000 10 25,000 10 20,000 7 25,000 10 16,000 7 20,000 10 150,000 20 90,000 20 100,000 10 Cost ANNUAL COST 9,000 5,000 5,000 5,200 600 4,500 2,500 3,000 2,500 2,300 2,000 7,500 4,500 10,000 63,600 APA main office administration,accounting,collecting, marketing expenses. TOTAL SYS TEM 1 132,000 $1,538,300 "'k S.L. 1.C. Service Life Initial Cost G-8 - TABLE 2.(Continued)--ITEMIZED OPERATION &MAINTENANCE COST ESTIMATE SYS TEM 2.DEVIL CANYON AND WA TANAY Devil Canyon Watana Personnel 700 MW 600 MW Watana Supervisory Control from Devil Canyon Increase base staff of System 1. Overtime Government Contributions Foreman Pay 2 Assistant operators @ 2 Electricians @ 2 Mechanics @ 1 Maintenance man @ Miscellaneous 11.00 13.00 13.00 11.00 hr. " " $45,760 54,080 54,080 22,880 176,800 10,000 16,000 5,000 31,000 Vacation travel Employee training Supplies,Services &Materials Supplies and Services 3,000 1,000 90,000 10,000 104,000 Equipment 2 Pickups 1 Snow tractor ~<1.C. 12,000 8,000 a;'t:s.L. 7 7 2,000 1,000 3,000 APA main office administrative,accounting,collecting &marketing expense TOTAL ADDITIONS TO SYSTEM 1 SYSTEM 1 TOTAL SYS TEM 2 30,000 344,800 -.-L...2)8,300 $1,883,100 1/Same operation and maintenance estimate used for System #2,#3,and #5. G-9 TABLE 2.(Continued)--ITEMIZED OPERATION &MAINTENANCE COST ESTIMATE SYSTEM 4--DEVIL CANYON AND WATANA AND VEE - Vee Personnel Add to System #2: 300 MW 1 Heavy equipment operator @ 13.00 hr. 2 Electricians @ 13.00 " 2 Mechanics @ 13.00 " 2 Maintenance men @ 11.00 " 1 Operator @ 13.00 " 1 Assistant operator @ 11.00 " Total Wage Grade Overtime Government Contributions Foreman Pay Total Fringe Benefits Miscellaneous Vacation travel Employee training Supplies,Services and Materia1s--Powerp1ant &vehicles Total Miscellaneous Equipment,Operation &Maintenance,Annual Replacement Cost D-8 Maintainer Pickups -(4) Dump truck Firetruck Sno tracs -(2) Backhoe Hydraulic Crane,20 ton Total APA main office administration,accounting,collecting, marketing expenses. Total Additions to System 2 System 2 $27,040 54,080 54,080 45,760 27,040 22,900 $230,900 10,000 20,800 5,000 35,800 6,000 2,000 50,000 58,000 9,000 5,000 3,400 2,500 2,500 2,300 2,000 4,500 31,200 30,000 385,900 1.883,100 _. TOTAL SYSTEM 4 G-IO $2,269,000 ))TABLE3.OPERATLNANDMAINTENANCECOSTSUMMA.RYT--~'-'Sy-;t~-;;-2--'l-SY~e;;~i--'-r---Syste;;;4'--&DevilCanyon&DevilCanyon,DevilCanyon,Watana.YI\·Jatana&Dena1iHatana,Denali,-._~---_..f-----....«••••---.-.----f-.--..----------____..-U~.._NumberDollarsNumberDollarsNumberDollars".NumberDollars1_."-~-_._---_..----_..-I1,124,7001,332,5001,332,5001,599,2007777313838·47218,000322,000322,000380,000--6360066.60066.60097.8001,406,3001,721,ioo1,721~1002,077,000-132,000162,000162,000192,000---.-o'1,538,300I1,883,1001,883,1002,269,000III":~ISyst-~_;m#2,.II•\!AnnualcosttoreplaceTelephone,travel,supplies,services,training,linespray,campmaintenanceAPAmainofficeadministration,accounting,collecting,marketingexpenseDirectcosts,COLA,benefits,overtimeNumberofclassifiedpersonsNumberofwageboardpersonsisce11aneous:Personnel:._-,<.",--_.'-.'-.',-,~/Syst~,:~rQ#5cost\-/(c'jid.bethesanH~':aEquipment:TOTALSubtotalMarketingandAdministrationI--"---·__·__·~··_-----·-~·--·-IISystem]IDevilCanyonDenaliI-.._+~II-'I-' Table4.ReplacementCostsSystem#1DevilCanyonandDenaliSystem#2&#3DevilCanyonandVIatana(includesDenali)CosttoConstructFeatureAnnualReplace-mentFactorCosttoConstructAnnualReplace-mentCostCosttoConstructAnnualReplace-mentCostSystem#4De'\'ilCanyon,Watana,VeeandDenaliAnnualReplace-mentCostPo~erplantTransmissiontowers,fixtures&conductors0.00120.0001----..$128,000,000$153,600$283,600,000$340,30085,200,0008,500150,000,00015,000$404,400,000$485,300163,400,00016,300GJI........NSubstationsandswitchyards0.00399,400,00036,700198,00025,100,00097,900453,20029,900,000116,600618,200PowerplantTransmissiontowers,fixtures&conductorsSubstationsandswitchyards~0.00120.00010.0039System#5Watana(el.2,200)andDevilCanyon$301,191,000$361,400180,362,00018,00035,235,000137,400516,800) 100 Mdf:ls APA 2-74 SCALE ~-------.-o so .~..Q 0°:~.·PR'fC~W"-LjAM .....~.~i~ u.s.DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION UPPER SUSITNA BASIN LOCATION MAP G-13 SECTION H TRANSMISSION SYSTEM UNITED STATES DEPARTMENT OF THE INTERIOR Alaska Power Administration Upper Susitna River Hydroelectric Studies Report on Transmission System December 1975 Contents Title 0_ Part I -INTRODCCTION . . . . . . . . Purpose and Scope . . . . . . . . Alternative Plans for Upper Susitna Hydroelectric Development Previous Studies Acknowledgements Part II -SUMMARY . Part III -EXISTING TRANSMISSION SYSTErv~S Anchorage -Cook Inlet Area Fairbanks -Tanana Valley Area Clennallen and Valdez Area . . Part IV -TPANSMISSION CORRIDOR STUDIES f\1dhod of Evaluation The Corridors Susitna Corridor Nenana Corridor Delta Corridor Matanuska Corridor Available Data Location Considerations Climate and Elevation Topography . . . . . Soils and Foundation Vegetation Wildlife . . . . . . . Vis ual Aspects Socio-Economic Aspects Distance .... Relative Cost . .... Corridor Evaluations Project Power to Anchorage -Cook Inlet Area Project Power to Fairbanks -Tanana Valley Area Project Power to Valdez and Other Points on the Richardson Highway . i H-l H-l H-l H-l H-4 H-5 H-8 H-8 H-ll H-ll H-15 H-15 H-24 H-24 H-24 H-25 H-25 H-25 H-27 H-27 H-27 H-28 H-28 H-28 H-29 H-29 H-29 H-32 H-32 H-32 H-34 H-37 Title Part V -TRANSMISSION SYSTEM DESIGNS AND ESTIMATES Electrical Design . . . . . . . . . . . . . Transmission Capaci ty . . . . . . . . . Voltage Selection and Line Characteristics Substations and Switchyards Power Flow Studies Reliability Right-of-Way Clearing Access Roads Structural Design Wind and lee Loading Snow .... Tower Design . . . . Foundations . . . . . Transmission Cost Estimates Alaska Cost Factors Transmission Line Costs Switchyard and Substation Costs Transmission Maintenance Facilities Estimates for Alternative Hydro Development Plans . . . . . . . . . . . . . . Transmission Estimates for Proposed Plan. Cons truction S ch edule . . . . . . . Other Transmission Alternatives . . . . Service Plans for Anchorage-Cook Inlet Area Service to Other Railbelt Power Loads . . . . i i Page No. H-38 H-38 H-38 H-40 H-48 H-48 H-49 H-49 H-49 H-50 H-50 H-52 H-52 H-52 H-56 H-57 H-57 H-60 H-60 H-60 H-64 H-66 H-66 H-66 H-67 List of Tables Page No. 1.Upper Susitna River Basin,Project Data Sheet. 2.Transmission Lines and Major Interconnections 3.Key to Alternative Corridors and Segments H-3 H-12 H-22 4.Relative Transmission Construction Costs for Alternative Corridors . . . . . . . . .H-30 5.Corridor Analysis:Project Power to Anchorage - Cook Inlet.. . . . . . . . . . . . . . . .H-33 6.Corridor Analysis:Project Power to Fairbanks - Tanana Valley Area . . . . . . .H-35 7.Comparison of 230 and 345 kv Systems 8.Transmission Line Characteristics H-41 H-44 9.Temperature,Precipitation,and Wind for Summit H-53 10.Typical ~ile Transmission Line Costs 11.Switchyard and Substation Costs H-58 H-61 12.Summary of Transmission System Cost Estimates H-63 iii List of Figures 10.Transmission System Layout 11.Substation Layout . . . . . 12.Alternative Transmission Line Structures 1.Upper Susitna Basin Location Map Pa~]'Jo. H-2 H-9 H-lO H-14 H-16 H-17 H-18 H-20 H-21 H·-42 H-46 H-54 H-65 Alternati ve Transmission Corridors Alternati ve System Plans The Railbelt.. . . . . Potential Transmission Corridors Transmission Corridor Segments Existing Transmission Systems -Cook Inlet Area Existing Transmission Systems -Anchorage fl.rea Existing Transmission Systems -Tanana Valley flrea . 13.Transmission System Layout . 2. 3. 4. 5. 6. 7. 8. 9. iv Part I INTRODUCTION Purpose and Scope This report covers the transmission system studies by the Alaska Power Administration for the proposed Upper Susitna hydroelectric development.The studies are of pre-authorization or feasibility grade. They consist of evaluation of alternative corridor locations from the viewpoints of engineering,costs,and environment;studies of transmission systems needed for alternative project development plans;and consider- ation of alternative transmission technologies.These studies deal with general corridor location;the more detailed studies following project authorization would include final,on the ground route location. The engineering and environmental evaluations for the transmission systems are parts of the same study,and Alaska Power Administration's environmental assessment for the transmission system is a companion report to this volume. Alternative Plans for Upper Susitna Hydroelectric Development Figure 1 shows general locations of the potential uni ts of the Upper Susitna Project in relationship to the Alaska Railbelt.The four key Upper Susitna damsites are Devil Canyon,Watana,Vee,and Denali. The Corps of Engineers proposes an initial development including the Devil Canyon and Watana sites with the Denali site considered as a potential future stage.Table 1 summarizes data on energy and power capability and costs for this proposed plan and the principal alternative system for developing the Upper Susitna hydroelectric potential.System #5 is the Corps proposed plan. Previous Studies There is a fairly substantial backlog of power system and project studies relevant to the current evaluation of the Upper Susitna River Project.A partial bibliography is included in the power market report. The previous studies most relevant to power market and transmission system planning include: 1.Advisory Committee studies completed in 1974 for the Federal Power Commission 1s new Alaska Power Survey.The studies include evaluation of existing power systems and future needs through the year 2000,and the main generation and transmission alternatives available to meet the needs.The FPC summary report for its new survey is not yet available. DEPARTMENT OF THE It--TERIOR ALASKA POWER ADMINISTRATION UPPER SUSITNA BASIN LOCATION MAP Appendix IFIGUREH-l.SCALEH-2 .......__-==-....:o?:===:::::::~5~O~=~~~~~-J100Mileo;. APA 2-74 AlternativeSystemPlansInstalledCapacity&FirmEnergyW.S.el.P.O.L.DevilSystemM.S.L.DateCanyonWatanaVeeSystemTotalInstalledFirmInstalledFirmInstalledFirmInstalledFirmSecondaryCapacityEnergyCapacityEnergyCapacityEnetgyCapacityEnergyEnergylOOnMillion1000Million1000Million1000MillionMillionkwkwhkwkwhkwkwhkwkwhkwhSystem#1--DevilCanyon145019855802497Denali253519905802497701System#2DevilCanyon145019856002628Watana20501990470205910704687946System#3DevilCanyon145019857003066Watana205019906702935Denali2535199513706001350System#4DevilCanyon145019857133119Denali25351990Vee230019953001314Watana19052000421184014346273640System#5Watana220019867923101DevilCanyon14501990776304815686149701::C-i)::oI)::oi::JWC:O~~~Notes:System#5istheproposedinitialdevelopmentplan.0-::c......DataisfromCorpsofEngineersstudies.IX......n1 Appendix I H-4 2.A series of studies for Railbelt area utilities include assessments of loads,power costs,and generation and transmission alternati ves. 3.Previous work by the Alaska Power Administration,the Bureau of Reclamation,the utility systems,and industry on studies of various plans for Railbelt transmission interconnections and the Upper Susitna hydroelectric potential.The most recent of these are the t-l!ay,1974 Status Report on the Devil Canyon Project by APA and the September,1974 Reassessment Report on Upper Susitna Ri vel'Hydroelectric Development prepared for the State of Alaska by the Henry J.Kaiser Company. It should be noted that many of the studies listed in the bibliography represent a period in history when there was very li tile concern about energy conservation,growth,and needs for conserving oil and natural gas resour.ces.Similarly,many of these studies reflected anticipation of long term,very low cost energy supplies.In this regard,the studies for the new power survey are considered particularly significant in that they provide a first assessment of Alaska power system needs reflecting the current concerns for energy and fuel conservation and the environment,and the rapidly increasing costs of energy in the economy. Acknowledgements We have attempted to reference principal data sources in the text.The corridor studies utilized data from many different sources--USGS mapping; ERTS photo mosaics obtained through the Geophysical Institute of the University of Alaska;soils survey and snow survey information from Soil Conservation Service reports for portions of the corriclors;resources maps and reports from the statewide resources inventory by the Resources Planning Team of the Federal-State Land Use Planning Commission;the State of Alaska's Regional Profile for the South central Region;climate records from the National Weather Service;and other data sources. The Bonneville Power Administration provided technical assistance in several ways:participation in the aerial and surface reconnaissance of the potential corridors;structural designs anq unit costs for transmission lines and substations;consultations on the transmission environmental assessment and reviews of design and cost studies prepared by APA. The electric utilitity systems of the Railbelt area provide the Alaska experience base for considering future transmission systems;utility personnel provided valuable assistance through consultation on their transmission system experiences and practices and on alternative plans for transmitting Susitna power to the load centers. Part II SUMMARY 1.The main elements of the study were:(1)evaluation of alternative corridors for locating project transmission lines considering environ- mental,engineering,reliability and cost aspects;(2)preparation of designs and cost estimates for the transmission systems needed for alternative project development plans. 2.The power market analyses (APA report on project power markets) show that the bulk of the project power would be utilized in Fairbanks - Tanana Valley and Anchorage -Cook Inlet areas,with smaller potential markets in the Glennallen and Valdez areas and other points along the Richardson Highway.Because of the relatively large demands,electric service to the Anchorage and Fairbanks areas i.s the largest single consideration in design of project transmis- sion facilities.Service to the other areas would be added when feasible. 3.The corridor evaluation started with map identification of all potentially feasible corridors and a field reconnaissance which eliminated those for which topography,elevation,and climate factors would be unacceptable.The remaining corridors were then evaluated in more detail to determine their relative advantages and disadvant- ages.Much of the detail of this evaluation is presented in the APA environmental assessment of the project transmission facilities. 4.It was concluded that the most desirable corridor location would follow existing surface transportation systems whenever possible. The principle disadvantage of such location is line visibility from the existing road and rail systems.Careful attention to use of natural vegetation and topography to screen the lines,locating the lines at an appropriate distance from roads,and selection of non-reflecting materials in final route selection and design would minimize visibility problems;it is recognized that even with best location and design,portions of the line would be highly visible.Significant advantages of locating the lines near existing surface transportation sy stems include minimi zing requirements for new access roads,savings in costs for construction and operation and maintenance,a significant improvement in reliability,and avoiding need for pioneering new corridors in presently undeveloped areas. Appendix I H-5 Appendix I H-6 5.Except for constricted passes through the mountains,the proposed corridors should be considered as very broad and general locations within which many alternatives are possible for final route locations.The final route locations would be determined through detailed post authorization studies. 6.The most serious conflicts in the final route selection will likely be encountered in the Nenana Canyon route through the Alaska Range.The Fish and Wildlife Service has recommended that a route west of the Parks Highway be selected through the Nenana Canyon to minimize possible conflicts with raptor habitat.Any route through the Canyon area would involve lines visible from portions of l\lount McKinley NC!tional Park and the FWS proposal would place portions of the route within park boundaries.AP A considers use of the corridor through the Nenana Canyon will result in substantially less environmental damage than would the pioneering of new corridors through the Alaska Range. 7.Additional conflicts are anticipatfod in final route selection along the approaches to Anchora.ge because of the Knik Arm,and topography.and land use and ownership patterns on possible routes around Knik Arm.Cost estin1 ates presented in this report assume delivery of project power to points on the CEA transmission system north of Knik Arm.It is recognized that the detailed studies following authorization would need to consider several alternative plans to transmit power across or around Knik Arm to Anchorage. 8.The initial set of transmission plans and estimates were prepared for use in evaluating the alternative Susitna hydroelectric develop- ment plans.It was found that conventional overhead lines at 230 kv and 345 kv would be suitable for the distances and amounts of power invol ved.The initial plans used double circui t lines on a single set of towers and assumed deli very points at Fairbanks and Anchorage. 9.As a result of review by area utilities,the Bonneville Power Administration,and others,the transmission plan and cost estimate for the initial hydro development plan (Watana and Devil Canyon)was modified to incorporate:the added costs for two single circuit lines in lieu of double circuit lines;an additional substation in the general vicinity of Talkeetna;and a switching station in the vicinity of Healy.The resulting trans- mission plan includes:two single circuit 230 kv lines from Watana to Devil Canyon (30 miles),two single circuit 230 kv lines from Devil Canyon to Fairbanks (198 miles)within intermediate switching station at Healy;and two single circuit 345 kv lines from Devil Canyon to points on the north shore of Knik Arm (136 miles) with an intermediate substation in the vicinity of Talkeetna.The estimated construction cost based on January ]975 price levels is $256 million.It is estimated that three years would be required for construction of the transmission facilities following completion of detailed route studies and final designs and acquisition of necessary rights-of-way. 10.Rough plans and estimates were prepared for transmission systems to deliver project power to Glennallen and other points along the Richardson Highway,and results are summarized along with econOIric analyses of such plans in the AP A power market study. 11.Alternative transmission technologies were considered in plan selection,including DC systems and underground lines.With exsiting and likely near future technology.reliability and cost considerations appear to rule out use of underground systems for the lines under consideration.Operating characteristics of DC systems would essentially rule out their application for an initial system to distribute project power to Railbelt power markets. 12.The general corridor locations and transmission designs and estimates are considered adequate for purposes of demonstrating project feasibili ty . Appendix I H-7 ..-_._._-_.-.•._-_._---------------_._-- Part III EXISTING TRANSMISSION SYSTEMS Appendix I H-8 The power market studies make it very clear that a major part of the project power would be utilized in the Anchorage -Cook Inlet and Fairbanks -Tanana Valley areas,respectively.Additional potential power markets exist in the Glennallen and Valdez areas and along the Alyeska pipeline. Anchorage-Cook Inlet Area The five electric utility companies serving this area are: Anchorage Municipal Light and Power (AML&P) Chugach Electric Association (CEA) Matanuska Electric Association OvillA) Homer Electric Association (HEA) Seward Electric System (SES) Alaska Power Administration operates the Eklutna Hydroelectric Project and markets wholesale power to CEA,AML&P,and MEA. AML&P serves the Anchorage Municipal area.CEA supplies power to the Anchorage suburban and surrounding rural areas and provides power at wholesale rates to HEA,SES,and MEA.The HEA service area covers the western portion of the Kenai Peninsula including Seldovia, across the bay from Homer.MEA serves the town of Palmer and the surrounding rural area in the Matanuska and Susitna Valleys.SES serves the city of Seward. The utilities serving the Anchorage-Cook Inlet area are presently loosely interconnected through facilities of APA and CEA.An emergency tie is available between the AML&P and Anchorage area military installations. The existing transmission systems in this area are indicated on Figures 2 and 3.Table 2 has a summary of existing lines and interconnections. The area presently has a total of about 545 circuit miles at 33 kv or higher voltage. CEA has under construction a 230 kv overhead line around Knik Arm to Anchorage including interconnections with the MEA and APA systems. The initial phase is now under construction;initial operation will beat138kv. ISTING TRANSMISSION SYSTEMS COOK INLET AREA x~-x-x-x 33 KV Transmission Line .·-..·-x-·-x 69 KV Transmission Line x-··-x-··-x 115 KV Transmission Line ..··-x-·-x 138 KV Transmission Line Scale in miles LOCATION MAP A ~. \ -'~. r .~.~ CHAKACHAMNA LAKE ---_._----_.__.-_..... o 20 40 60 80 A.P.A.-JULY 1974 Appendix I FIGURE H-2 H-9 :r:""Tl;t:>I_-0......G"J-0aero:;o::::lrr.0-......:r:xIw......CEA115KVCEA115KV>~100<tof0It)a:a..wcISu..J<[::El.L~~0---_..,,IICDIAPA115KV}:'::~>~:l::"~~~:~~~>~~·~;·(g:~·~;,\\:···:·.::,tf·P.bW·ERPLANTIAML~P)'.?:::::'.,.':;:~It):.::'\~AMLElP34'"V\Ia..\ /NORTHERNBLVD~"...jr-_I@.34.5KV®~CEA34.5KV(j)(<IDIICEA138KV<t/"'_~§~/'~1..-/~>------.>'\//~t-'-.~/10w~>-IOw""-~. w3:':'::/.ra:I.r<['-../.It)tilIt)TUDOR-lROADo~ua:W~(.)w(j)CEA34.5KV\.j~1~Scaleinmileso2468UNITEDSTATESDEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONEXISTINGTRANSMISSIONSYSTEMSANCHORAGEAREA,APA-JUIY19~~ For purposes of this study,it is assumed that Susitna power would be made available at a substation in the vicinity of Talkeetna and at points on the CEA 230 kv loop around Knik Arm,and that the power would be wheeled over the CEA and APA Eklutna systems to serve Anchorage. As discussed later in the report,the actual plan for delivering project power in the Anchorage-Cook Inlet area will need to be determined through detailed systems studies following project authorization. Fairbanks-Tanana Valley Area The two electric utilities in this area are: Fairbanks Municipal Utility System (Ff\,1lTS) Golden Valley Electric Association (GVEA) FMUS serves the Fairbanks municipal area,while GVEA provides service to the suburban and rural areas.The Fairbanks area power suppliers have the most complete power pooling agreeIl"ent in the State. FMUS,GVEA,the University of Alaska and the military bases have an arrangement which includes provisions for sharing reserves and energy interchange accounts.In addition,GVEA operates the Fort Wain-- wright steamplant under an agreement with the army. The existing transmission systems are indicated on Figure 4;Table 2 includes a summary of the lines and existing interconnections. The delivery point for Upper Susitna power to the GVEA and FMUS systems is assumed at the existing Gold Hill substation of GVEA near Fairbanks. Glennallen and Valdez The Copper Valley Electric Association serves both Glennallen and Valdez.Radial distribution lines of CVEA extend from Glennallen 30 miles north on the Copper River,55 miles south on the Copper River to Lower Tonsina and 70 miles west on Glenn Highway. CVEA has given some consideration to a 115 kv intertie between Valdez and Glennallen.For this study,it is assumed that project power would be delivered to the CVEA system at Glennallen. Appendix I H-ll :I:---I::t:>I::t:>"'C......co"'CN,l'D1Tl~c..:I:.....I><N.....TransmissionLinesandMajorInterconnections(Note:Linesunder33kvnotincluded)TransmissionLinesInterconnectionsYAreaOwnerDesignationKVMileageWithSubstationFairbanksGVEAHealy-GoldHill138104U.ofAlaskaUniversityGoldHill-JohnsonRd.6945Ft.WainwrightFt.WainwrightZehnder-Fox698EielsonAFBEielsonMisc.withinCity693Ft.GreelyHighwayParkGoldHill-MurphyDome34.524FMUZehnderFox-PilotBluff34.518FMUMW1i.Pwr.Plt.-Zehnder691Ft.Wainwright19thStreet(SeeGVEA)Anchorage-MEAEagleRiverTap-WalterCookInletPipple1153/4APAPalmerPalmer-NWKnikArmSym.34.542APAReedPalmer-Lucas-Reed34.518APAEagleRiverAPAEklutna-Palmer11515AML&PAnchorageEklutna-Reed-EagleRiver-Anchorage11532CEAAnchorageElmendorfAnchorageAML&PAnchorageAPASub-CitySystem34.523-1/3(SeeAPA) (cont.)TransmissionLinesandMajorInterconnections(Note:Linesunder33kvnotincluded)TransmissionLinesInterconnection!IAreaOwnerDesignationKVMileageWithSubstation-Anchorage-CEABeluga-International13852(incl.4(SeeAPAandHEA)CookInletmi.submarine)(cont.)AnchorageAPASub-BerniceLake2/U5l65-iCooperLake-QuartzCreek6963LinestoSoldotna3/6986Misc.withinAnchorage34.531HEAKasilofSub-Homer6961CEAKasilofKenaiAreaLine3312-~yListedonlyonceundersubstationownership(NationalDefense-ownedsubstationsarelistedundertheinter-connectedutility).yIncl.TudorSub.-InternationalandspurlinetoPortage.QuartzCreek-BerniceLakeportionleasedfromHEA.3/LeasedfromHEA:Soldotna-QuartzCreek,Soldotna-BerniceLake,Soldotna-Kasilof.:I:-1:t:>oI:t:>o"'0......o::l"'CWrtl)IT1:::::lc..:I:......1><N...... UNITED STATES DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION EXISTING TRANSMISSION SYSTEMS TANANA VALLEY AREA Appendix I FIGURE H-4 H-14 : I )( I:.; X \~ \- \HEALY \ ~ AIRPORT WAY FAIRBANKS o LOCATION MAP / \ \ x-x-x-x 33 KV Transmission Line x-·-x-·-x 69 KV Transmission Line )t-..-x-..-x I 15 KV Transmission Line )t---x-..·-x 138 KV Transmission Line Scale in mi les 20 40 60 A.PA.-JULY 1974 Part IV TRANSMISSION CORRIDOR STUDIES Appendix I H-15 This portion of the transmission study evaluates alternative corridors for transmission facilities to deliver project power to the power markets. The term"corridor"means general location of transmission facili ties, and the studies are intended to show relative merits of alternative transmission corridors from the viewpoints of the environment,engineer- ing,economics.and reliability. Width of corridor is not defined precisely.The actual right-of-way needed is fairly narrow.Except where limited by specific physical or environmental considerations,the corridors themselves should be considered several miles wide. The major mountain ranges--Alaska,Talkeetna,and Chugach--limit the range of choice in corridors (See Figure 5).The higher elevations in these mountains are completely unsuitable for transmission lines, and there are relatively few low-elevation passes through these ranges. Away from the mountains,a wide range of locations could be considered. Figure 6 illustrates on a very broad scale,the alternatives for locating the lines.From the project south to the Anchorage area,the heart of the Talkeetna mountains can be avoided by corridors which generally follow the Susitna River Valley (Susitna Corridor)or ones that pass to the east of the mountains and approach Anchorage from the Matanuska Valley (Matanuska Corridors). From the project north to the Fairbanks area,the options for crossing the Alaska Range are limited to the pases in the Nenana River drainage (Nenana Corridor)or to the east generally along the Richardson Highway (Delta Corridor). Method of Evaluation A preliminary identification of potential corridors was made utilizing large scale topographic maps and photo mosaics prepared from satellite photography. This involved primarily identifying potentially feasible passes through the moun tains.Figure 7 indicates the corridors identified in this step. The second step involved an aerial reconnaissance to determine which of these corridors were actually feasible for constructing lines.Several were found to have tlfatal flaws"or characteristics that would preclude their use for transmission lines.Reasons for eliminating corridors at this stage included completely unsuitable topography,obstruction by major glaciers,or excessive elevations. ~s~UNITED STATES DEPARTMENT or THE INTERIOR ALASKA POWER ADMINiSTRATION 1 5 75 A PA-JUU ~7!'> !50 RAILBELT Scale -Mile\, 25---o THE DEN@U--STATE PARK ! [J Appendix I FIGURE H-5 H-16 ITED STATES DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION Appendix I FIGURE H-6 H-17____._3 100 125 A.P.A-Morch 1975 75 Paxson 50 ( Scale in miles DEVIL CANYON PROJECT ALTERNATIVE SYSTEM PLANS •FAIRBANKS Healy NENANA ICORRIDOR Cantwell • / ----_.-.~- - IOOMlle'i50 SCALE ~~-----.-o DEPARTMENT OF THE INTERIOR A LASKA POWER ADM IN I STRATION UPPER SUSITNA RIVER PROJECT POTENTIAL TRANSMISSION CORRIDORSAppendixI FIGURE H-7 H-18 The remaining potential corridors,which are indicated on Figure 8, were then analyzed in more detail.The basis for the analysis was individual corridor segments which are indicated on Figure 9.For convenience,the alternative corridors and the individual segments were numbered as shown on the maps.Table 3 provides a key to this numbering system.All of these remaining corridors are considered physically feasible for transmission lines. The evaluation is intended to identify the relative advantages and disadvantages of utilizing the alternatives for transmission lines. The steps in the evaluation were: (1)Description and inventory by segment of the key resources that would be impacted by a transmission line. (2)Evaluation of probable impacts of locating,building,and operating transmission lines for each segment. (3)Determination of relative cost and reliability for lines utilizing the alternative corridors. (4)Summarization of advantages and disadvantages from the viewpoint of environment,engineering,costs,and reliability of service. (5)Selection of preferred corridors. The comparisons between alternatives used parameters that could be quantified,such as length and cost,while judgment ranking was used for those parameters that could not be readily quantified. The descriptions and inventory and evaluation of impacts are reported in more detail in th eA.P .A.en vi ronmen tal as s ess men t,wi th only summary information presented in this report.The description and inventory grouped data and interpretations under nine broad categories: (1)Topography and Geology (2)Soils (3)Vegetation (4)Wildlife (5)Climate (6)Existing Developments (7)Land Ownership and Status (8)Relation to Existing Rights of Way (9)Scenic Quality and Recreation Appendix I H-19 Appendix I FIGURE H-8 H-20 Nenono-3 DELTA CORRIDOR •Paxson ___---.,M~ArrTANUSKA ~~-----CORRIDOR ·Palmer UNITED STATES DEPARTMENT OF THE INTERIOR ALASKA POWER ADMI NISTRATION DEVI L CANYON PROJECT AL TERNATIVE TRANSMISSION CORRIDORS Scale in miles 3 50 75 100 125 A.P.A-Morch 1975 •Paxson DEVIL CANYON PROJECT TRANSMISSION CORRIDOR SEGMENTS Scale in miles STATES DEPARnAENT OF THE INTERIOR ALASKA POWER ADMINISTRATION Appendix I FIGURE H-9 d-21 ~~~iiiiiiiiiii~~Iiii!il~~~~iiiiiiiiiiiiiiiiii~~~~S~ 50 75 100 125 A.P.A-Morch 1975 Key to .Alternative Corridors and Segments Corridor Susitna #1 Susitna #2 Susitna #3 Susitna #4 Matanuska #J Matanuska #2 Segments of Corridor Susitna Corridors 1,3,7,8,9 1,2,7,8,9 1,4,5,8,9 1,4,6,8,9 Matanuska Corridors 8,9,20,22 8,9,18,21,22 Nenana Corridors Approxiwa te Total Mileage 166 170 159 164 258 385 Appendix I TABLE H-3 H-22 Nenana #1 Nenana #2 Nenana #3 Nenana #4 Nenana #5 Delta #1 9,8,7,10,13,16 228 9,8,7,10,12,14,17 250 9,8,7,10,12,14,15,16 261 8,9,11,14,15,16 223 8,9,11,14,17 212 Delta Corridor 8,9,18,19 280 The probable impacts are identified and described under five broad categories in the environmental assessment. (1)Soils (2)Vegetation (3)Wildlife (4)Existing Developments (5)Scenic Quality and Recreation. Alternative corridors were compared utilizing a judgment ranking under each of the five impact categories. The cost aspect of the corridor analysis is premised on rough recon- naissance costs for a double circuit steel tower line located in the corridor.The estimate included access facilities using the following criteria: (1)For corridors within approximately five miles of existing surface transportation,pioneer access suitable for four-wheel drive vehicles would be provided where terrain and soils are favorable.Where soils are not suitable for pioneer road type of access,no road is provided and overland access for construction and operation and maintenance would be limited to winter periods with adequate snow cover.Otherwise,access would be by helicopter. (2)For corridors pioneering into new areas,or more than five miles from existing surface transportation,the estimates include a new road to minimum standards suitable for access to the line and to provide appropriate environmental protections--adequate erosion control,permafrost protection.etc.Such new roads would be single lane,gravel surface,with periodic passing areas. Relative cost and difficulty for operation and maintenance activities are shown by judgment ranking for this analysis.This reflects ease of access,terrain,climate,and other factors that bear on the operation and maintenance activities. Reliability is also shown by judgment ranking reflecting relative hazards to major outages and relative difficulty of making repairs. Appendix I H-23 -"'-------------_._, Appendix I H-24 The Corridors The alternatives represent only general corridors,and do not attempt to define an actual right-of-way.Thus,the alternatives do not distinguish among many minor variations,and as a result,are fairly flexible. Only brief descriptions of the corridors are included here since details of resources and identified impacts are available in the APA environmental assessment.As a summary reference,the IIInventory ll and IIImpact" matrixes from the assessment are appended to this report. Susitna Corridors There are basically four feasible corridors which connect Devil Canyon to Anchorage via the Susitna drainage.All four of these incorporate the segment that runs from the endpoints of Point MacKenzie to Talkeetna, so this segment can,therefore,be treated as separate and not included in a comparison of the alternative corridors. Of the four corridors that run from Talkeetna to Devil Canyon-Watana, the first follows the Susitna Valley north,paralleling the Alaska Railroad to Gold Creek,where it leads east to tie into Devil Canyon-Watana (Susitna -1). The next,and farthest west,parallels the Anchorage-Fairbanks Highway through Denali State Park,along Troublesome Creek,eventually leading east to tie into Gold Creek and Devil Canyon-Watana (Susitna -2). The third goes up the Talkeetna River and gaining the ridge to the east of Disappointment Creek,leads north to the ridge leading to Devil Canyon (Susitna -3). The fourth and most easterly corridor follows the Talkeetna River to Prairie Creek,which it follows to Stephan Lake,halfway between Devil Canyon and Watana (Susitna -3). Nenana Corridors There are five feasible corridors connecting the Upper Susitna with Fairbanks by way of the Nenana River.The first is a corridor paralleling the highway and railroad from Gold Creek to Cantwell,to Healy,and to Fairbanks (Nenana -1). The second duplicates the first corridor to Cantwell,but then leads east paralleling the Denali Highway,as far as Wells Creek and north over the pass to Louis Creek,continuing over the Dean Creek Pass to the Wood River.It then follows the Wood and Tanana Rivers to Fairbanks (Nenana -2). The third corridor,(Nenana -3),duplicates the second to Dean Creek, where it then continues up Yanert Fork and over Moody Pass,ending up at Healy and joining the first corridor. Corridor four (Nenana -4)leaves Watana and heads north,emerging onto the Denali Highway near the Brushkana River.It then leads west.goes up Wells Creek,and joins corridor three to Healy and Fairbanks. Corridor five starts the same way as corridor four,except instead of going over Moody Pass to Healy,it leads east over Dean Creek into the Wood River,and then leads north to Fairbanks,(Nenana - 5). Delta Corridor For this study.only one corridor along the Delta River was considered. This corridor leaves Watana damsite and leads east down Butte Creek to the Denali damsite and continues east along the Denali Highway. It then proceeds north near Paxson over the Isabel Pass and parallels the Richardson Highway into Fairbanks.Alternatives could be very limited in the vicinity of Isabel Pass.but additional alternatives could be considered in the Tanana Valley and Copper River Valley. Matanuska Corridors Two corridors were considered utilizing the Matanuska Valley as access to Anchorage.The first corridor connects Watana to Vee damsite, leads southeast to the Little Nelchina River,which it follows to the Glenn Highway and corridor one,which it follows to Point MacKenzie (Matanuska-l). The second follows the Delta route to Paxson,then leads south to Glennallen. It then goes west,over Tahneta Pass,and into the Matanuska Valley, tying into Point MacKenzie (Matanuska-2). Available Data A variety of data sources were used in the study,including U.S. Geological Survey maps at scale 1:250,000 and 1:63,360,ERTS photo mosaics,and uncontrolled aerial and ground photo mosaics of critical areas. -----------------"- Appendix I H-25 Appendix I H-26 The data compiled by the Resource Planning Team of the Land Use Planning Commission in their statewide inventory studies was used extensively.This data is available in a set of 1:250 ,000 overlay maps and supporting reports.It includes information on geology,vegetation. wildlife habitat,soils,water resources,recreation,land status,archaeological and historic sites,and other resource aspects. More detailed soil survey data from the Soil Conservation Service is available for some corridor segments.U.S.Geological Survey permafrost maps were utilized. Available climatological data from the National Weather Service were utilized for Fairbanks,Anchorage,Palmer,Talkeetna,Summit,McKinley Park,Clear,and other locations in the Railbelt. In September,1974,personnel from APA and Bonneville Power Administration made an aerial and surface reconnaissance of the alternative corridors to examine critical areas and obtain first-hand information on the terrain and other factors. Over 2,600-35mm slides were taken,processed,indexed,and catalogued to record and preserve details of the observations.Interviews with management and maintenance personnel of the two major utilities operating transmission lines in the marketing areas of Anchorage and Fairbanks were made.The objective was to determine the criteria,problems, experience,and suggestions they could offer in planning,locating, and designing an upper Susitna transmission system. Panoramic photo mosaics were prepared using photographic color prints made from the slides to help evaluate the impact of a transmission line constructed through critical,scenic,and other potential problem areas.Reports covering impressions and data gathered from the reconnais- sance and rough cost evaluations were prepared to further assess the meri ts of the various alternative corridors. Uncontrolled aerial photo mosaics of the alternative corridors were prepared to assist in the resolution of questions in critical problem areas. Several environmental impact statements were used to provide information not readily available elsewhere. Aerial photographs of the various corridor routes are available from Bureau of Land Management,U.S.Geological Survey,and Alaska State Highway Department. Numerous magazines,newspapers,publications,and other reports were also incorporated into the study data. Location Considerations Corridor location objectives are to obtain an optimum combination of reliability and cost with the fewest environmental problems.In many cases.these objectives are mutually compatible.However. this is often not the case with respect to line visibility and scenic impacts.Throughout the corridor evaluation.the question arises of whether it is more desirable to place lines relatively close to existing surface transportation facilities or to pioneer new corridors where the line would be seen by few people. The following items are major factors considered in the evaluation of altern ati ve corridors: Clima te and Elevation Winds.icing.snow depth.and low temperatures are very important parameters in transmission designs,operation.and reliabili ty.Experience with existing lines of the area utili ties indicates few unusual climatic problems for the areas away from the mountains.except for winter low temperatures that inhibit operation and maintenance activities. The climate factors become more severe in the mountains.High winds. longer winters,more snow.and colder average temperatures are charactistic.APA believes that elevations above about 4000 feet in the Alaska Range and Talkeetna Mountains are completely unsuitable for locating major transmission facilities.Significant advantages in reliability and cost are expected if the lines can be kept well below 3000 feet in elevation. Extreme winds in excess of 100 fv1PH are expected for exposed areas and passes in the mountains.The potential for icing is probably not as serious as in coas tal areas of Alaska.so long as the lower elevation passes are used.The corridors under consideration do not involve unusually heavy snow depths. Topography Topography plays a threefold role in transmission location--0)it affects cost of construction.inspection,and maintenance;(2)it affects visual impact;and (3)it affects reliability. Transmission costs rise dramatically in areas of broken or steep terrain-- towers require special foundations,individual design for variation in leg lengths to accommodate sloping sites.Broken relief also increases cost by increasing the number of towers required per mile due to decreased Appendix I H-27 Appendix I H-28 spacing.These same topographic characteristics increase access difficulties which,in turn,increase access road costs,time spent in transit,and difficulty in transporting construction and maintenance supplies and materials.Inspection of lines in rough terrain changes a routine operation into an ordeal or increases costs by making utilization of aircraft a necessity. It is increasingly difficult to visually shield a line and its clearing scar as topographic relief increases.This is especially true under certain orientations,particularly when the line runs parallel to a steep side hill in view of a road,railroad,or other view point. Conditions of instability pose physical threats to the reliability of the line.Broken terrain,steep slopes,or conditions in which the angle of the terrain exceeds the angle of repose of the soil,increase the chances of land,rock,or mud slides.Snow slides are an additional hazard on steep slopes. Soils and Foundation Transmission lines are less affected by soils and foundation limitations than are roads,railroads,and pipelines.Good examples of this exist in the GVEA and CEA transmission systems which traverse sensitive muskeg and permafrost areas with few problems.This requires designs of tower foundations that are compatible with the soil situation and careful design and control of access for construction and operation and maintenance. Vegetation Heavily forested areas in the valleys would require essentially continuous clearing of the transmission right-of-way.The higher elevations and muskeg areas would involve essentially no clearing.Impacts are di verse: in the forested areas,opportunities to shield the lines from view are good,but the continuous scar is generally unavoidable.At higher elevations, there would be very little impact on vegetation,but line vis ability is high. Wildlife There will be some habitat changes due to clearing and access facilities. Probably the major consideration for wildlife is the extent to which the transmission lines change the access to land by people.This is subject to some control by managing access,but new corridors and new access roads tend to encourage public use and thus increase pressures on fish and wildlife. Visual Aspects More than any other factor in transmission location,the visual aspect is controversial and subject to a wide range of opinion.Existing criteria provide for utilizing natural vegetation and topographic relief as a shield, minimizing crossings over roads,and otherwise utilizing route selection and orientation techniques to minimize vis ability .Other options include use of non-reflective conductors and towers.At best,such measures are only partly effective. Socio-Economic Aspects Land status,ownership,use.and value are important factors in the location of transmission corridor alignments . Consideration of existing uses,costs of right-of-way and easements tend to influence the selection of alignments which will affect other uses least.Hunting lodges.tourist accommodations,and facilities with high scenic uses or values,such as parks.scenic viewpoints,recreation areas,etc.,also should be avoided or skirted by transmission corridors or the corridor should be well screened. Recent trends in land management tend to favor the corridor concept for combining transportation,utility,and communication facilities. The rationale is to confine man's influence to a relatively small zone Distance The economics of transmission line construction and maintenance dictate that line distances should be kept as short as possible while recognizing other criteria.This will result in lower construction costs and shorter construction periods.Lower operation and maintenance costs will result because it will take less time to find a fault on a shorter line.A shorter line will be subjected to fewer hazards because it is physically smaller. Power and energy losses will be lower on a shorter line. Other impacts of a shorter line include less clearing--fewer trees must be cut,thus less land will be subjected to man's influence and less wildlife habitat will be altered. Longer lines require higher voltages with a resultant requirement of higher capacity and larger conductors,towers,and hardware.This combination increases costs as well as right-of-way width. Appendix I H-29 :I:-1)::>I)::>-0Wco-oormfTl::::s0-:::I:......IX+:>~RelativeTransmissionConstructionCostforAlternativeCorridors-UpperSusitnatoAnchorageSusitnaCorridorsMatanuskaCorridorsS - IS - 2 S - 3 S - 4M - I M-2-Length,miles166170159164258385Max.elevation,feet2,1002,1003,8002,2003,0004,000Clearing,milesMed.heavy166146132142166228Light---10101317157None---1417975AccessRoads,milesNewroads00123284644-Wheeldriveaccess122126122104138290None444425283631TowerConstruction,milesHeavysteel444468623094Normal12212691102228291ComparativeCost,$1,000Clearing3,0003,0003,000 3,0006001,100Access8,000 8,2009,50010,90019,90027,200TransmissionLines82,000 84.00081,30082,200132,700196,200Total93,00095,20093,80096,100153,200224,500• :::r::-l~I~"OW0:1"0......r(!)l'T1:::Jc..:::r::......I X.j:>.......(continued)RelativeTransmissionConstructionCostforAlternativeCorridors-UpperSusitnatoFairbanksNenanaCorridorsDeltaCorridorN - 1 N - 2N -3N - 4 N-5 DLength,miles228250261223212280Max.elevation,feet2,4004,3004,000 4,0004,3004,000Clearing,milesMed.heavy12513912799III114Light0000021None103III134124101145AccessRoads,milesNewroads013650961821684-Wheeldriveaccess972211997082None13110292303030TowerConstruction,milesHeavysteel155194188121127198Normal7356731028582ComparativeCost,$1,000Clearing400400400200300400Access7,80021,80017,40020,500 24,80027,300Transmissionlines77,20084,90088,50075,00071,40094,800Total85,400107,100106,30095,70096,500122,500 Appendix H-32 Relative Cost Rough reconnaissance cost estimates were made for transmission lines in the alternative corridors to illustrate relative costs.The estimates are summarized on Table 4. The estimates reflect access,clearing,and line construction costs . For the Susitna and Matanuska Corridors,they are premised on a 345 kv double circuit line;the Nenana and Delta Corridors are based on a 230 kv double circuit line. Corridor Evaluations This section summarizes results of the evaluations and identification of preferred corridors.In the assigned ranking,lower numbers reflect a preference or fewer impacts. Project Power to Anchorage-Cook Inlet Area Six corridors were considered.A summary of the analysis is presented on Table 5. The Matanuska Corridors were found to offer no significant advantage for major power supplies to the Anchorage-Cook Inlet area.Disadvantages include added length,significant distance at higher elevations which could complicate construction and operations,and additional impacts associated with more access and longer lines. The four Susitna Corridors assume a common alignment from Talkeetna to Pt.MacKenzie.This should be depicted as a fairly broad corridor at this time,since the terrain is quite favorable for transmission and there would be a great deal of flexibility in locating the final route to minimize impacts and interference with existing developments.This will require very careful route studies. North of Talkeetna,there are some cri tical factors of terrain and access. The feasible routes between Devil Canyon-Watana and the Talkeetna area are: S-l,generally along the Alaska Railroad. S-2,which generally follows the Anchorage-Fairbanks Highway S-3 and S-4,which approach Talkeetna through the Talkeetna River Valley. S 3,the shortest route,also involves the most difficult terrain and highest elevations.This would be the least advantageous from the viewpoint of building and operating a transmission line. CorridorAnalysis-ProjectPowertoAnchorage/CookInletAreaSusitnaCorridorsMatanuskaCorridorsAnalysisFactor:S - 1 S - 2 S-3 S - 4 M - 1M - 2Length,miles166170159164258385Max,elevation,feet2,1002,1003,8002,2003,0004,000Ranking112134EnvironmentalImpactsSoils121122Vegetation231345Wildlife123343Existingdevelopments332133Scenicquality/recreation:Developedareas332133Remoteareas123443Ranking131344Costs--Construction112134Operationandmaintenance112133Ranking112134ReliabilityExposuretohazards112123Easeofrepair122233Ranking123244SummaryRanking123244:::X:-l):o(preferredI):0"0corridor)wOJ"0wrrol'Tl::l0-:::x:-"IXU'I..... Appendix I H-34 Reconnaissance of the four Susitna Corridors indicates that vegetation and topography would facilitate screening of lines to minimize visual impacts. S-4 would involve pioneering a new road up the Talkeetna River to the Stephan Lake area;similarly,S-3 would involve considerable new road construction in the Talkeetna Valley.S-2 would traverse the existing Denali State Park,which would require a new access between Gold Creek and the Anchorage-Fairbanks Highway.The aspects of the State Park for S-2 and the new corridors required for S-3 and S-4 were major factors in the evaluations. There does not appear to be a great deal of difference in terms of impacts on soil,vegetation,and wildlife,except that involved in new access road construction. Cost aspects are quite similar for S-l,S-2,and S-3;S-l appears most desirable from the reliability viewpoint because of proximity to existing transportation and lower elevations. The preferred corridor is S-]. Project Power to Fairbanks-Tanana Valley Area Six corridors were considered,and a summary of the analysis is presented on Table 6. The Delta Corridor involves several disadvantages which relate primarily to longer distances and a considerable distance at fairly high elevations. The potential advantages are avoiding entirely the Broad Pass-Nenana Canyon area and the potential for extending electric service to the Paxson area and portions of the Upper Tanana Valley. Much of the Delta Route is in areas where lines would be quite visible because of limited vegetation and limited opportunity to shield lines with topography. The Nenana alternatives fall into two general classes:(1)corridors paralleling the existing transportation corridor containing the Anchorage- Fairbanks Highway and the Alaska Railroad,and (2)alternatives to the east of this corridor through the Alaska Range to the Fairbanks area. N-1 follows the Alaska Railroad to the Broad Pass area and Cantwell, proceeds through the Nenana Canyon to Healy,and generally parallels the existing GVEA transmission line from Healy to Fairbanks. ')CorridorAnalysis-ProjectPowertoFairbanks/TananaArea')NenanaCorridorsDeltaCorridorAnalysisFactor:N-1N - 2 N - 3 N - 4N - 5D--Length,miles228250261223212280Max.elevation,feet2,4004,3004,000 4,0004,3004,000Ranking133233EnvironmentalImpactsSoils132233Vegetation223213Wildlife132333Existingdevelopments322212Scenicquality/recreation:Developedareas322113Remoteareas132232Ranking133213Costs--Construction142356Operationandmaintenance142353Ranking142354ReliabilityExposuretohazards143244Easeofrepair142343Ranking132233SummaryRanking142234:I:--1)::>(preferredI)::>"'CWco"'Ccorridor)(J'1r(l)rn:::l0-:I:......IXen...... Appendix I H-36 N-l is an obvious first choice from the viewpoint of transmission line construction and operation because of the proximity to existing transportation throughout its length and use of the most favorable pass through the Alaska Range. Because of proximity to existing transportation,impacts on soil,vegetation, and wildlife would likely be less severe than the other alternatives which pioneer routes in remote areas. N-l also has obvious disadvatages in that the area from Broad Pass through the Nenana Canyon offers very limited opportuni ties to shield transmission lines from view,and from Cantwell to Healy,the route parallels the eastern boundary of Mt.McKinley National Park.Portions of the line would be visible from the Park Headquarters.The environmental assessment includes a number of photos illustrating terrain and vegetation in this area. The other Nenana alternatives provide a basis for exploring feasibility of avoiding the areas of Broad Pass and the Nenana Canyon. N-l,N-2,and N-3 follow the same alignment from Devil Canyon to Cantwell. N-2 and N-3 follow east along the Denali Highway,and then head north through the Alaska Range about 30 miles east of the Nenana Canyon. N-2 crosses two passes and returns to the Nenana River at Healy just below the Nenana Canyon.From Healy to Fairbanks,N-2 follows the existing GVEA line,as does N-l, N-3 continues north through a third pass and approaches Fairbanks through the Wood River Drainage. N-4 and N-5 avoid both the Broad Pass area and the Nenana Canyon. They head north from the vicinity of Watana Dam to Wells Creek and then north to the Fairbanks area using the same route as N-2 and N-3, respectively. The primary advantages to this group of alternatives are avoiding highly scenic areas along the Alaska Railroad and Anchorage-Fairbanks Highway. N-2 and N-5 additionally are removed from the Railroad and the Highway between the Alaska Range and Fairbanks. Other than visual impacts in presently utilized areas,N-2,N-3,N-4, and N-5 seem to offer no significant advantages.Because they involve pioneering new routes in remote areas,including substantial requirements for new access roads,the four alternatives would have greater impacts on soil and wildlife than would N-l. APA believes it would be feasible from the engineerng viewpoint to construct and operate transmission lines in any of these corridors.However, because of remoteness,more rugged terrain,and the high elevation passes,alternatives N-2,N-3,N-4,and N-5 would involve significantly higher initial cost as well as operational costs and significantly lower reliability than alternative N-l, On the grounds of environment,engineering,costs,and reliabili ty , N-1 is the preferred corridor. Project Power to Valdez and Other Points on the Richardson Highway Analysis has not been completed of alternative corridors for delivering power to the Glennallen area and other points along the Richardson Highway. The basic alternatives appear to be: (1)Cons truc ting a line from the Palmer area to Glennallen. (2)Constructing a line from the Devil Canyon-Watana area to Glennallen. (3)Completing a loop from Palmer to Glennallen and then north along the Richardson Highway to the Fairbanks area. Existing studies by APA and area utilities evaluate possible electric service to points along the Richardson Highway from Glennallen to Valdez with and without power to electrify the pumping stations along the Alyeska pipeline.The studies indicate 138 kv system would suffice if pipeline pumping loads are not included,and that a 230 kv system would be needed with pipeline pumping.Neither of these alternatives would provide significant additional capacity to transfer power between the Anchorage and Fairbanks areas. APA's present thinking is that a 138 kv or 230 kv line to Glennallen, either from Palmer or the Devil Canyon-Watana area should be evaluated for possible inclusion in early stages of project construction,and that completing a loop along the Richardson Highway may be desirable as a later stage of the project. Appendix I H-37 Part V TRANSMISSION SYSTEM DESIGNS AND ESTIMATES This part summarizes designs and estimates for transmission systems for the four alternative development plans referenced in Table 1. The transIY'ission studies assume lines located in the preferred corridors from the project to the Anchorage and Fairbanks areas. Transmission to the Glennallen area is treated as a separate alternative. Electrical Design Transmission Capac~ Based on firm power capability of the alternative systems,the relative size of power markets in the Anchorage-Cook Inlet and Fairbanks-Tanana Valley areas,and an assumed margin for flexibility, design capacities for the transmission systems were assumed as follows: Project Installed Capaci ty MVV A__s_s_u_m_e_d_T_r_an_s_m_i_s_s_i_o_n_C_a.....p_a_c_i ty,MW Anchorage Fairbanks Anchorage + Fairbanks System #1: Devil Canyon+Denali System #2: Devil Canyon+Watana System #3: Devil Canyon+ Watana+Denali System #4: Devil Canyon+Watana +Vee+Denali System #5: Watana+Devil Canyon 580 1,070 1,370 1,434 1,568 500 1,000 1,200 1,200 1,200 250 300 300 300 300 750 1,300 1,500 1,500 1,500 Appendix H-38 As discussed subsequently,these design capacities are not necessarily ultimate capacities of the transmission system.For example,with minor cost additions and nominal increases in losses at peak loading,the transmission system capacity for the proposed plan (System #5)could be upgraded by at least 50%without basic change in voltage,tower design, or conductors. Voltage Selection and Line Characteristics Based on nominal carrying capacities,both 230 kv and 345 kv systems entered consideration.Because reliability has high priority, the systems used multi-circuit configurations,except System #1. Conductor sizes,spacings,stranding,and bundling were assumed for each voltage.The following table summarizes these assumptions. It also indicates a measure of capability to be subsequently discussed. Design studies will determine final parameters,including series compensation. 230 kv 345 kv ACSR ACSR Pheasant Rail 1272 MCM 954 MCM 54/19 45/7 Simplex Duplex 16" 20'28' Voltage Conductor: Type Name Size Stranding Number per phase Flat Spacing: Conductor Phase Towers: Material No.per mile Right-of-Way Width .!/ Single Circuit Capacity without Compensation Steel or Aluminum 6 125' 29,300 MW-mi. Steel or Aluminum 5 140' 82,200 MW-mi. The two voltage options indicate minimum and maximum considerations. Alaska's first 230 kv line is now being constructed in the Anchorage area will be operated initially at 138 kv.Based on a conservative or "safe"stability criteria of 25 0 power angle between high voltage buses,the 138 kv transmission system is capable of less than 12,000 MW- mi.That is,the power transmitted times miles transmitted must be less than 12,000.The minimum acceptable capability north or south from the Susitna Project is over 50,000 MW-mi.and eventually could be as high as 188,000 MW-mi.Clearly,even a compensated 138 kv system of several lines would be inadequate and uneconomical. Under the same stability criteria,a single circuit,uncompensated 230 kv transmission line has a capability of about 29,300 MW-mi. A 345 kv duplex system carries 82,000 MW-mi.A 500 kv line is capable of 186,000 MW-mi.,which is too large to apply to the Susitna Project. The voltage alternatives therefore are bracketed by the standard 230 kv and 345 kv systems. Conductors chosen for use in this study have not been subjected to detailed economic evaluation.The 1272 MCM applied to the 230 kv option is often used for that voltage but seldom is it exceeded.The 345 kv 954 MCM duplex conductor has been used extensively.Thermal constraints necessitate larger conductors with larger kv systems.The carrying capacity of the 345 kv transmission voltage can be accommodated by a simplex conductor, and there are many such in the U.S.However,the conductor size approaches an unwieldy diameter.Duplex bundling widely used in 345 kv systems reduces the diameter,retains thermal capacity,and increases stability limi t.Higher voltages also produce more corona phenomena.This is 1/Would be 50%greater for two single circuit lines on adjacent righ ts-of-way . Appendix I H-39 Appendix I H-40 relieved somewhat by larger conductors.The 954 MCl-/duplex conductor approximates an average among all these factors for use in feasibility studies. DC options were considered only briefly.Operating characteristics made DC systems inappropriate for a first major Railbelt intertie. The line lengths between the Project and the Anchorage and Fairbanks areas are 136 and 212 miles,respectively.It is generally considered that DC economics would not be attractive at these relatively short transmission distances. Table 7 summarizes a comparison of 230 kv and 345 kv systems for the alternative hydro development systems.On the basis of this compari- son,a 230 kv transmission plan was selected for System #1 with two circuits to Anchorage and a single circuit to Fairbanks.For Systems #2, #3,#4 and #5,two 345 kv circuits would be needed between Devil Canyon and Anchorage,and two 230 kv circuits between Devil Canyon and Fairbanks. The assumed transmission system layout is indicated on Figure 10. The main lines go from the Devil Canyon switch yard to substations at Point MacKenzie and Ester-Gold Hill.Systems #2,#3,and #5 have a switchyard at Watana and two 230 kv circuits from Watana to the Devil Canyon switchyarc:1.System #4 has a similar switchyard at Vee and two 230 kv circuits from Vee to Watana. All transmission plans are relatively simple,radial systems that have distances,voltages,and loads well within experience of existing systems in the South 48.Hand studies were used to determine required compensation and system losses and to check for voltage drop and stability. Table 8 summarizes line characteristics and system losses for the transmission systems.The 230 kv line from Devil Canyon to Fairbanks in System #1 appears to be close to stability limits.All of the double circuit lines could provide considerable additional capacity by adding series compensation. Substations and Switchyards The transmission studies included switch yard and substation design, layouts,and cost estimates.Switch yard and substation designs assumed the nominal "breaker and one-half"scheme.Each line and transformer is protected by one and one-half circuit breakers.This is a compromise between the cost of a "two-breaker"plan and the reduction in reliability inherent in a "one-breaker"scheme.Figure 11 indicates substation layouts at the load center and switchyard layouts at powerplants . Comparisonof230and345KVSystemsLine(PheasantConductor):204036,60048,800AlternativeSystemandInstalledCapacityAnchorageLine(136mi.)CapabilityRequirement(MW-mi.)230kvCompensatedTransmissionCompensation(%)MaximumCapability(MW-mi.)(percircuit)NumberofCircuitsRequiredPowerLoss(%)#1(580MW)70,00024.8#2(1070MW)140,00036.5#3(l370MW)164,0005058,60037.7#4(1434MW)164,0005058,60037.7#5(15681lW)164,0005058,60037.7Line(RailConductor):82,200 82,200345kvDuplexUncompensatedTransmissionMaximumCapability(MW-mi.)82,200(percircuit)NumberofCircuitsRequired1PowerLoss(%)2.922.923.582,20023.582,20023.5Line)PheasantConductor):51255,00033,300FairbanksLine(198mi.)CapabilityRequirement(MW-mi.)230kvCompensatedTransmissionCompensation(%)MaximumCapability(MW-mi.)(percircuit)NumberofCircuitsRequiredPowerLoss(%)50,0001760,00024.660,0001233,30024.660,0001233,30024.660,0001233,30024.6Line(RailConductor):82,200 82,200:J:-i»I:x:-"'O~c;o"'O......rro(Tl:::lc..:::I:......IX"-..l345kvDuplexUncompensatedTransmissionMaximumCapability(MW-mi.)82,200(percircuit)NumberofCircuitsRequired1PowerLoss(%)2.312.712.782,20012.782,20012.7 100Mil••o 50 U.S.DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION UPPER SUSITNA RIVER PROJECT TRANSMISSION SYSTEM LAYOUT SYSTEM IAppendixI FIGURE H-IO-l. H-42 U.S.DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION UPPER SUSITNA RIVER PROJECT TRANSMISSION SYSTEM LAYOUT SYSTEMS 2,3,84 SCALE ~~------=-...--2 o 50 100Mil•• Appendix I 'FIGURE H-IO-2 H-43 :I:-l:J::>I:J::>"O~t::C"O~rCl>m::l0-:I:......IXCOTransmissionLineCharacteristicsTransmissionDataForAlternativeSystemsSystem System SystemSystem#1#2#3#4DevilCanyontoPt,MacKenzie036miles):System#5Numberofcircuits22222Nominallineloading,MW5001,000 1,2001,2001,200Voltage,kv230345345345345Conductor(ACSR)1,272954954954954Losses:PeakMW2428404040Peak%53333EnergyMWH/yr..!/19,10022,70032,70032,700 32,700DevilCanyontoEster-GoldHill098miles):Numberofcircuits12222Nominallineloading,MW250300300300300Voltage,kv230230230230230Conductor(ACSR)1,2721,2721,2721,272 1,272Losses:PeakMW1712121212Peak%74444EnergyMWH/yr..!/13,90010,00010,00010,000 10,000.!/At40%LineLoadingFactor. (continued)TransmissionDataForAlternativeSystemsSystemSystemSystemSystem#1#2#3#4WatanatoDevilCanyon(30miles):System#5NumberofcircuitsNominallineloading,MWVoltage,kvConductor(ACSR)Losses:PeakMWWatanatoVee(40miles):2222470670721750230230 2302301,2721,2721,2721.272Lessthan2%ofpeak:J:-I~I)::0"0+:=-OJ"OU1rCD1T1~0-:J:....I><CO......NumberofcircuitsNominallineloading,MWVoltage,kvConductor(ACSR)Losses:PeakMWLessthan2%ofpeak23002301,272 SUBSTATION LAYOUT I.WATANA 230KV SWITCHYARD c:'---§-/'---§-/~0>.c:c:.. 0 OJU> 0 .~en u '--@--/'--@--/'-@--/..en0_en OJ OJ o '5 :::I E- - u CD ..~ OJ .!::,20c:u en u ~>c:>~~o~-'---@--/'--@--/-0.-0 en _........-[]_/-l:l~~OJ~ .-N .:NEI&.'enN u~ c:0 0 Et=t2. DEVICE SIZE No.OF UNITS Circuit Breakers 230 KV 8 Sta.Svc.,Reac.,Capacitor Mach.KV 5%of above [2.FAIRBANKS 230 KV SUBSTATIONc: 8 .:; OJ °en.E·5"'~1------_...I OJuc:...:=·u ~>._~ l:lo'e~..........,t------...... en'c:Not= Appendix I FIGURE H-ll H-46 Power Transformers Circuit Breakers Sta.Svc.,Reac.,Capacitors 230/138 KV-200MVA-30 230 KV Tertiary KV 2-30 Units 6 5%of above 3.DEVIL CANYON SWITCHYARD-c ':;C '---@I---/'---@}--/C eno~--c·-~·u ~a61>o.~.!:~~-u-0 m 61>Crt')-~'--@}--/.!:~.!:!N en -;;0en'JenN ort')'E en '-N>en.en oK ~>.!!!NccCc0~E ~~0 en rt')C...rt')~;f N N vJw 2-400 MVA BankWvv IV\('A 230/345 KV IV\('A ...t6I~Clu ene·~~en Ou m ~ "5~m c lO 'In ~«~ DEVICE Power Transformers Circuit Breakers Sta.Svc.,Reac.,Capacitors SIZE 2-400 MVA Bks.230/345 KV 230 KV-345 KV Tertiary KV No.OF UNITS 7-10 Units (133.3 MVA ea.) 6-230 KV,3-345 KV 5%of above 4.ANCHORAGE 345 KV SUBSTATION _en._- ~.~'--@--/ o'u->-+-----_..........~~en =10 ~c~m ort').s:::.'--@--/'cnN ~CB .!!?-z E c_+------..........en O c>. C C ~8 Power Transformers Circuit Breakers Sta.Svc.,Reac.,capacitors 750 MVA Bks.-345/230 KV 345 KV Tertiary KV 7-10 Units (250 MVA eo) 6 5%of above Note:Single-phase (10)transformers are connected 3 per 30 bank with 10 spare per switchyard or substation. Ap:Jendix I FIGuRE H-ll d-47 Appendix I H-48 In addition to the breakers,each end of the transmission line has transformers,bus work,and,where pertinent,reactors and capacitors. Transformers were provided between transmission voltages. Power Flow Studies As stated previously,hand studies were used to determine transmission system design parameters and losses.Several computer runs were made at the Bonneville Power Administration to check basic system performance under load and with assumed outages.The computer studies confirm that the system design assumptions are adequate for feasibility study purpose,that is,to provide an adequate basis for determining physical and financial feasibility of the system.The more detailed studies for actual design would include the full range of systems analysis appropriate for a major new power system. Reliability The preliminary transmission evaluations assumed multiple circui t configuration;substations,and switchyards use the "breaker and one-half"scheme.The various systems assume two circuits on a single tower except for a single circuit 230 kv line to Fairbanks in System #1.Tower designs are free-standing,steel with NESC "heavy" loading for the low-level portions of the corridors,and an additional safety factor for rugged terrain and mountain passes. There have been no specific studies of system reliability.Based on experience elsewhere,the double circuit lines would have very high reliability.They would be vulnerable to outages due either to tower failure (landslides,etc.)or to a failure caused by interference with both circuits (such as an aircraft accident). The next higher level of reliability would be to utilize two single-circuit lines.If these were in close proximity to each other,they could utilize the same access facilities.Right-of-way and clearing requirements would increase. Some further reduction in vulnerability to serious outages would be obtained by parallel or looped lines in separate rights-of-way. During review of the preliminary studies by the Bonneville Power Administration and area utilities,strong preference was indicated for placing each circuit on a separate set of towers.The reviewers felt the added reliability of such a plan would justify the additional costs . Right-of-Way Estimated width and area of rights-of-way are as follows: Line 230 kv,single or double circuit 2-230 kv,adjacent ROW 345 kv,single or double circuit 2-345 kv,adjacent ROW ROW Width 125 190 140 210 Acres Per Mile 15.2 22.8 17.0 25.5 Over most of the route,the normal ROW width would be adequate for both the lines and the access facilities. Detailed analysis of land ownership would be needed as a part of final route selection.It is anticipated that some private lands will be crossed and that easements would be obtained (rather than purchased in fee).Where the lines are on public land,it is assumed that ROW can be obtained without cost to the project.The estimates include an allowance of $700 per acre for easements on portions of the lines which are assumed to involve private lands.On the basis of judgment evaluation of broad land ownership patterns for each corridor segment, approximately 75 miles along the Devil Canyon to Fairbanks and 89 miles along the Devil Canyon to Point MacKenzie route may require easements. Clearing Heavily forested areas in the Susitna and Tanana Valleys would require essentially continuous clearing.However,tree size varies from small to medium and clearing operations are not particularly difficult. Based on USGS maps with vegetation overprint and Forest Service maps showing timber types,approximately 231 miles of line under System #1 and 261 miles for System #2,#3,#4,and #5 would require essentially continuous clearing.A unit cost of $500 per acre for clearing was assumed,based on recent highway construction bids.Acreage for clearing were premised on 4.6 acres per mile for the 230 kv lines and 5.1 for the 345 kv lines. The remaining portions of the lines would involve only nominal clearing of occasional small trees and some brush removal. Access Roads Since the preferred corridor is in close proximity to existing surface transportation,requirements for new access roads are minimal.Where soils and topography are favorable,a primitive access road suitable Appendix I H-49 Appendix I H-50 for four-wheel dri ve vehicles is assumed.Such access roads would consist of little more than a trail along the right-of-way with occasional cross drainage structures and small amounts of gravel fill.Access to existing roads would be provided periodically.No major stream crossings would be involved.These rudimentary roads would be used in both the construction and operation and maintenance phases. Between Gold Creek and the project powerplants,it is assumed that the access roads built for dam construction would be adequate for transmission access. For the remainder of the line,an estimated 219 miles is suitable for four-wheel drive access roads.The estimates include $50,000 per mile for roads. From Gold Creek to Cantwell and Healy,terrain,vegetation,and soils do not favor use of the primitive access roads.It is assumed that no new roads would be provided for this line segment.For this portion of the line,access would be limi ted to helicopter and winter over-snow vehicles for construction and operation and maintenance.Significant portions of the existing GVEA and CEA transmission systems have been built and operated in this manner. Structural Design Wind and Ice Loading There is not a great deal of hard data on wind and icing extremes for the selected corridors.However,there is a sufficient experience base to establish that wind and ice conditions should not be unusually severe. Existing transmission lines in the Matanuska-Susitna Valleys and from Healy to Fairbanks have not experienced any unusual icing problems. Hoarfrost is a fairly common experience in winter,but not a problem for HV lines.Climate and topography generally do not favor formation of heavy glaze or rime ice--during most of the year it is either too hot,too cold or too dry for heavy icing to occur. This is markedly different from condi tions in some mountainous areas along the Gulf of Alaska where temperature and moisture condi tions favorable to heavy icing are quite common. Key stations for wind data are at Anchorage,Talkeetna,Summit,Nenana, and Fairbanks.All of these stations have fairly lengthy records of wind observations;none have recorded unusually severe winds.The available recorded data is on the basis of fastest mile,so actual peak gusts would be higher. Period Maximum Source of Wind Recorded (all from National Station Record MPH Weather Service) Anchorage 1914-1974 61 1974 Annual Station Summary Talkeetna 1940-1974 38 1974 Annual Station Summary Summit 1941-1974 48 1974 " " " Nenana 1949-1967 less than 40 NWS Uniform Summary,Part C Fairbanks 1929-1974 40 1974 Annual Station Summary It is known that more severe winds occur through the Nenana Canyon. During initial operations of the Healy-Fairbanks 138 kv line,3 towers in the immediate vicinity of Healy were lost due to high winds.The problem area is right at the mouth of Nenana Canyon.The Alaska State Highway Department operated an anemometer at the Moody Bridge site in Nenana Canyon for a short period during construction of the Anchorage- Fairbanks Highway.1·1aximum recorded wind was 62 MPH,and a more severe wind storm was observed during a period when the recorder was not operating.Y The basic transmission cost data for this study are premised on the Bonneville Power Administration designs for National Electric Safety Code Heaving Loading assurnptions--4 pound wind concurrent wi th -J,"radial ice or an alternative 8 pound wind loading.The NESC loading assumption is consistent with normal utility practice for this area and is considered adequate for the portions of the line from Talkeetna to Anchorage and from Healy to Fairbanks. It is expected that more severe wind load criteria would be appropriate for portions of the line through the Broad Pass area and the Nenana Canyon.A more detailed study of climate conditions for these corridor segments,including collecting additional wind data,would be needed along with the detailed design studies.This study makes allowance for more severe wind conditions in these areas by increasing tower steel 10 percent. 1/Communication from Alaska Department of Highways,June 1975.Appendix I H-51 Appendix I H-52 Very severe icing is not considered likely based on the topography and climate data,comparatively low elevations through the Alaska Range,and absence of reports of severe icing.The available data also indicates possibilities are remote for simultaneous occurrence of maximum wind and maximum icing.A summary of data for the station at Summi t follows.Heaviest winds occur from November to March when air temperatures are well below freezing. Snow Available snow depth data from Soil Conservation Service Snow Survey publications were reviewed prirr;arily to determine if there were any areas along the corridor where snow depths are large enough to affect tower designs. Standard tower designs assumed for this study are generally adequate to handle snow depths up to 10 feet.For areas of larger snow accumulation, added tower heigh t would be needed to obtain nec~ssary clearance. This is often handled by adding "snow legs"to standard tower designs. Based on the snow data,maximum snow accumulation well under 10 feet is expected over the entire route,except for occasional areas subject to drifting.The snow depthwill not likely affect transmission designs and costs significantly. Tower Design The cost estimates are premised on free-standing,steel-lattice towers. This assumption reflects fully-proven technology for which there is a good experience base in costing and construction methods. The final designs would consider several alternative designs and may result in selecting guyed towers for portions of the line and use of special tower designs in areas where the lines are most visible. Figure 12 indicates representative sizes and shapes for several 230 kv towers;345 kv towers are somewhat larger because phase to phase and phase to ground clearances must be 8 to 10 feet greater than for 230 kv. Foundations Available soils and foundation data include:detailed soil surveys from the Soil Conservation Service for part of the lower Susitna Valley and the immediate Fairbanks area;general geologic and permafrost maps from the USGS;1:250 ,000 scale reconnaissance level interpretation of soil types prepared by the Resources Planning Team of the Land Use Planning Commission;and data from route studies for existing transmission lines and highways.The environmental assessment includes a regional perma- frost map and strip maps showing general soil types for the corridors. Temperature,Precipitation,and Wind for Summit 0 Mean Wind Speed,MPHAverageTemperature,F Mean Maximum Minimum Precip. Month Month Month Inches Mean Fastest Mile Jan.0.8 7.3 -5.7 0.9 15.1 44 Feb.6.3 13.0 -0.5 1.17 11.9 46 Mar.10.4 18.7 2.0 1.01 11.0 48 Apr.23.4 32.7 14.0 0.64 7.6 33 May 37.4 45.6 29.1 0.72 7.7 28 June 48.8 57.9 39.7 2.18 8.3 29 July 52.1 60.3 43.9 2.98 7.8 30 Aug.48.7 56.1 41.2 3.25 7.4 26 Sept.39.8 47.1 32.5 2.75 7.5 37 Oct.23.7 30.1 17 .2 1.62 8.0 35 Nov.9.5 15.5 3.5 1.23 11.3 39 Dec.3.0 9.3 -3.3 1.17 12.7 44 Appendix I TABLE H-9 H-53 :I:"'T1)::oI.....':ID<J1G')"'O+:>cro;;O~IT1c........:I:XI::::;.....--------------------------------------------------------------------------..,1I..~('~~j\A1/~\\I/'---~.,_.._------------_.,--r-I31'\-I-CDm___~}L__SINGLECIRCUITSINCLECiRCUITFLATCONFIGURATIONDELTACONFIGURATIONFREE-STANDINGTOWERS-cor--r------54'.------IT,-I!V'"•"\ J_____----.L_GUYEDTOWERS'",.II.~~-4L..-i~L_.\;'1!\\/,\ \If\\II\VI--,]-.--------------S!NG~.ECIRCUiTFLATCONFIGURATION~:--::~-'---_.--------!y~---i\:r-~:~".;/1\"/(I~:'~'/r""\\//\\//\\II\~.-.LJ!\\______~_LSINGLEClhc.d:T~LATCONFIGURATIONDOUBLECIRCUITSTACKCONFiGURATIONNOTESmLJCTJRESDEPIC:[C"flRF:DE.SiGtJEDFOR230I"~.UNITEDSTATESDEcPArifMHIT(JTHEINTERIO~","AS>(/lP~'WEP./lDM'~<I'5TI'ATIONALTERNATIVETRANSMISSIONLINESTRUCTURESAP."-JA."'UAR:"d~ <0t-I-CDC1>SINGLECIRCUITDELTACONFIGURATIONGUYEDTOWER1--5@'~-fP=TJ==iIJIf!11II-<DIiI~SINGLECIRCUITMETALH-FRAMESTRUCTUREr-40'~rOMQI-0J ""SINGLECIRCUITMETALH-FRAMESTRUCTURE1-'56'•.:-~'....1.ii/"II~1l!\[;11!f.X__~__1(-------.l.L--\1I__SINGLECIRCUITWOODH-FRAMESTRUCTURESING.LECIRCUITWOODH-FRAMESTRUCTURE.NOTESTRUCTURESDEPICTEDAREDESIGNEDFOR230KV.UNIlEDSTATESDEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONALTERNATIVETRANSMISSIONLINESTRUCTURES::I:"T1)::oI....."'C~~~APA-JANCIARY1975,;o::::lrna......::I:><I...........N Appendix I H-56 Areas of muskeg,frost susceptible soils.and permafrost will require careful foundation design.It is estimated that up to about 30 percent of the line would require foundations designed specifically to accommodate these conditions.Experience suggests that such special designs would not involve major increased costs for the line. A number of different design approaches have been used.Portions of existing CVEA lines through muskeg areas that have considerable frost action have used guyed towers set on steel pile foundations. The GVEA Healy-Fairbanks line crosses some very sensitive permafrost areas.It also uses guyed towers,but the foundation is a single pedestal. A further option would be use of thermal pilings to keep foundations in a frozen state. Transmission lines for Canada's Nelson River Project use free standing towers with footings set on a grillage foundation to cross permafrost and muskeg.This technique involves setting a grillage of steel or timber below the active frost zone for the foundation.The estimates for this report are premised on use of the grillage foundations. This is a conservative assumption since much of the route will undoubtably be suitable for normal tower foundations --concrete footings under each tower leg.Foundation considerations will of course be a major consideration in the detailed route and design studies.following author- ization. Transmission Cost Estimates This section summarizes the transmission system cost estimates. The basic estimates are pren1ised on cost experiences of the Bonneville Power Administration with adjustments to reflect Alaska construction costs and January 1975 price levels.As noted previously.costs for rights-of-way.clearing.and access were estimated separately. The first set of estimates were prepared to allow comparison of the several alternative hydro development plans and were used in the Corps of Engineers scoping analysis. Further studies were made on alternative transmission plans for the proposed initial development plan (Watana and Devil Canyon)resulting in the transmission plan and estimate included in the project proposal. Alaska Cost Factors The basic cost data from BPA reflects Pacific Northwest conditions. Alaska construction would involve substantially higher labor costs and additional transportation costs to deliver materials fabricated in the South \148\1 to Alaskan construction sites. AP A derives"Alaska factors \I of 1.9 for labor and 1.1 for added transport- ation.The BPA data were separated into components of labor and materials and the appropriate factors were applied to estimate Alaska costs. The 1.9 labor cost factor is premised on a comparison of wage and fringe benefits data under recent IBEW contracts for the Anchorage and Portland areas with appropriate allowances for overtime and subsistance pay for remote work in Alaska. The 1.1 transportation cost factor is premised on current barge and rail tariffs between Seattle and various points along the Alaska Railroad, with an allowance for loading and unloading. Transmission Line Costs Typical mile costs for constructing transmission lines were furnished by the Bonneville Power Administration.These costs were itemized by major components and portions of costs for labor and material. APA adjusted these costs with the Alaska factors for labor and transport- ation derived above.The estimates are summarized on Table 10. The BPA typical mile costs were premised on January 1974 price levels and APA made adjustments to January 1975 prices.Based on advice from BPA personnel,tower steel costs were increased from $450 to $800 per ton.Other basic cost items were updated using USBR indexes. The estimates include allowances for:handling and storage of materials; contingencies and unlisted items;and overhead items.The allowance for handling and storage is 15%of tower steel costs plus 10%of other material costs.There is a 25%allowance for contingencies and unlisted items such as communications equipment and series compensation.The 20%overhead item includes surveys,designs,inspection,and contract administration. Appendix I H-57 Typical Mile Transmission Line Costs 230 kv Single Circuit Labor Materials 230 kv Double Circuit Labor Materials 345 kv Double Circuit Labor Materials January 1974 Costs,$1,000 Tower Steel 13.18 13.95 22.95 24.30 42.71 45.23 Conductors 10.49 13.73 16.26 27.47 18.31 37.48 Hardware & Accessories .82 1.64 4.00 Insul2.tors 1.14 2.28 4.21 Miscellaneous 4.41 3.58 4.41 5.05 4.41 9.24 Subtotal (Pacific NW)28.08 33.22 43.62 60.74 65.43 100.16 January 1975 Costs,$1,000 1/ Tower Steel 16.74 24.83 29.15 43.25 54.24 80.51 Conductors 13.32 17.44 20.65 34.89 23.25 47.60 Hardware & Accessories 1.04 2.08 5.08 Insulators 1.45 2.90 5.35 Mis cellaneous 5.60 4.55 5.60 6.41 5.60 11.73 Subtotal (Pacific NW)35.66 49.31 55.40 89.53 83.09 150.27 Alaska Factor 1.9 1.1 1.9 1.1 1.9 1.1 Alaska Cost 67.75 54.24 105.26 98.48 157.87 165.30 Subtotal 121.99 203.74 323.17 Handling &2/ 9.52 16.99 29.81Storage- Subtotal 131.51 220.73 352.98 Contingencies & Unlisted Items (25%)32.88 55.18 88.25 Subtotal 164.39 275.91 441.23 Admin.overhead, survey,design &inspection (20%)32.88 55.18 88.25 Total Alaska Con- struction Cost 197.27 331.09 529.48 Rounded 200 330 530 1/ Appendix I TABLE H-I0 2/ H-58 - Cost increase reflect following assumption: Tower Steel:Jan 1975 $800/ton =1.78 Jan 1974 $450/ton Other items based on USBR transmission cost index: Jan 1975 1.87 _27-1.Jan 1974 1.47 15%of tower steel cost plus 10%of other materials costs. Typical Mile Transmission Line Costs -cont. 345 kv Single Circuit Labor Materials January 1974 Costs,$1,000 Tower Steel Conductors Hardware & Accessories Insulators Mis cellaneous Subtotal (Pacific NW) 26.35 27.90 11.81 18.74 2.00 2.10 4.41 5.95 42.57 56.69 January 1975 Costs,$1,000 1/ Tower Steel Conductors Hardware & Accessories Insulators Mis cellaneous Subtotal (Pacific NW) Alaska Factor Alaska Cost Subtotal Handling & Storage Y Subtotal Contingencies & Unlisted Items (25%) Subtotal Admin.overhead, survey,design &inspection(20%) Total Alaska Con- struction Cost Rounded 33.46 15.00 5.60 54.06 1.9 102.71 197.57 17.67 215.24 53.81 269.05 53.81 322.86 320.00 49.60 23.80 2.54 2.70 7.60 86.24 1.1 94.86 Appendix I TABLE H-I0 H-59 cost index:Other items Cost increase Tower Steel: reflect following assumption: Jan 1975 $800/ton Jan 1974 $450/ton =1.7 8 based on USBR transmission Jan 1975 1.87 Jan 1974 1.47 =1.27 15%of tower steel cost plus 10%of other materials costs. 1/ 2/ Appendix I H-60 As noted previously,tower steel was increased 10%above that for the typical mile costs for portions of the line in higher elevations through the Alaska Range. Switchyard and Substation Costs Table 11 shows sample computations of switchyard and substation costs. These were estimated using basic cost data for major equipment items from Bonneville Power Administration's "Substation Design Estimating Catalog'!with price levels of January 1975.The major cost items are the transformers and circuit breakers.As in the transmission estimates, costs for the major equipment items were adjusted for Alaska labor and transportation costs.Additional allowances were made for:handling and storage (15%of material cost);contingencies and unlisted items (25%);and overhead (20%). Costs for individual switchyards and substations were determined by increasing the major equipment item as derived above by an additional 10%allowance for station service items. Transmission Maintenance Facilities The estimates include provision for transmission maintenance headquarters at roughly the mid-points of the Devil Canyon-Fairbanks and Devil Canyon-Anchorage lines.Each headquarters would consist of a lineman's residence.vehicle storage building,warehouse,and fenced storage yard. Estimates for Alternative Hydro Development Plans Table 12 summarizes cost estimates for transmission systems assumed for the Corps of Engineers scoping analysis of alternative hydro develop- ment plans.The plans include substations at Fairbanks and Point MacKenzie with switchyards at each powerplant.Transmission lines assumed for the scoping analysis are as follows: System #1 assumes a single circuit 230 kv line from Devil Canyon to Fairbanks and a double circuit 230 kv line from Devil Canyon to Point MacKenzie. The transmission plans in the scoping analysis for systems #2,#3, and #5 assume a double circuit line from Devil Canyon to Fairbanks, a 345 kv double circuit line from Devil Canyon to Fairbanks,and a 230 kv double circuit line from Watana to Devil Canyon.System #4 adds a 230 kv double circuit line from Vee to Watana. Switchyard and Substation Costs Part I -Sample Calculation,Derivation of Circuit Breaker and Transformer Costs Equipment Cost ($1,000 - Power Transformer 345/230 kv Labor Material January 1975 Costs) Circuit Breaker 345 kv Labor Material Equipment Cost Structures &Accessories Subtotal Alaska Factor Alaska Cost Subtotal Handling &Storage (15%of material) Contingencies and unlisted items (25%) Adminis trati ve overhead and design (20%) Total,Alaska Construction Cost Rounded 11 +5 16 x1.9 30 320 +138 458 x 1.1 504 534 76 +134 +107 851 850 15 +8 23 x1.9 44 265 +138--- 403 x 1.1 443 487 66 +122 +97 772 770 Part II -Sample Calculation,Devil Canyon Switchyard Cons truc tion Cos t January 1975 Costs Six -230 kv Circuit breakers 6 x $565,000 = Six -345 kv Circuit breakers 6 x $770,000 = Seven -345/230 kv Single phase transformers 7 x $850,000 = Subtotal 10%station service,capacitors,reactors Total Construction Cost $3,390,000 4,620,000 5,950,000 13,960,000 1,400,000 $15,360,000 Appendix I TABLE H-ll H-61 :::I:--f:t:>I:t:>"'CO'lOJ"'CNrrtlrn::l0-:::I:~.1)<....................SwitchyardandSubstationCosts(cont.)PartIII-Summary,System5SwitchyardandSubstationCostsDevilEster-PointIntermediateSwitchingWatanaCanyonGoldHillMacKenzieDel.PointStationSwitchyardSwitchyardSubstationSubstationSubstation(Compensation)CircuitBreakers8@230kv6@230kv6@230kv6@230kv5-345kv6-230kv6@345kv2@138kv2@138kv1-138kvTransformers---7@2@7@4@345/230kv.Y230/138kvY345/138kv.Y345/138kv1/ConstructionCost($I,OOO-January1975)4,97015,3609,15012,4207,8903,720.YSingle-phasetransformers2/Three-phasetransformers Summary of Transmission System Cost Estimates Length of line,miles Portion requiring easements, miles Portion requiring clearing, miles: Medium-Heavy None Access roads,miles: 4-Wheel Drive None Tower Construction,miles: NESC Heavy Added Steel (Mountains) Estimates for Scoping Analyses Clearing Easements Access Roads Transmission Lines Substations l!r Switchyards TOTAL System System System #1 #2-3-5 #4 334 364 404 164 164 164 231 261 301 103 103 103 219 219 219 115 145 185 195 195 195 139 169 209 Construction Costs ($1,000) System System System #1 #2 l!r 3 #4 1,010 1,210 1,210 2,240 2,410 2,410 14,240 14,240 14,240 87,190 151,960 165,700 19,320 41,900 46,870 124,000 211,720 230,430 Estimate for Proposed Plan (System #5) Construction Costs ($1,000) Clearing Easements Access Roads Transmission Lines Substations l!r Switchyards TOTAL Rounded 2,430 3,620 14,370 182,100 53,520 256,040 256,000 Appendix I TABLE H-12 H-63 Transmission Estimates for Proposed Plan On the basis of reviews of the preliminary designs by area utilities,the Bonneville Power Administration,and others,further consideration was given to alternative circuit configuration,alternative service plans for the Anchorage-Cook Inlet area,and sectionalizing the Devil Canyon to Fairbanks line.This resulted in the following changes in the transmission plan adopted for the proposed project:(see Figure 13) 1.Addition of a switching station at the approximate mid-point of the Devil Canyon-Fairbanks line (this is assumed at Healy and estimated added costs are $3.7 million). 2.An additional substation in the vicinity of Talkeetna which appears warranted by the pattern of load development in the MEA system (estimated added costs of $7.9 million). 3.Including costs for parallel single circuit lines on adjacent rights-of-way in lieu of the double circuit lines in the preliminary estimates (added costs of $32.7 million). With these changes,total construction costs of $256 million are included in the proposed initial development plan: Appendix I H-64 Item Transmission Lines: Clearing Rights-of-Way Access Roads Lines Subtotal,Transmission Line Switchyard and Substations: Fairbanks Substation Talkeetna Substation Point MacKenzie Healy Switchyard Watana Switchyard Devil Canyon Switchyard Subtotal,Switchyards and Substations Total Transmission Costs Rounded Construction Cost $1,000 2,430 3,620 14,370 182,100 $202,520 9,150 7,890 12,420 3,730 4,970 15,360 $53,520 $256,040 $256,000 Appendix I FIGURE 11-13 H-65 IOOMil•• --==SCALE-----------------------------=--.o 50 U.S.DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION UPPER SUSITNA RIVER PROJECT TRANSM ISS ION SYSTEM LAYOUT SYSTEM 5 Appendix I H-66 Construction Schedule It is estimated that actual construction of the backbone transmission system could be accomplished readily over a three-year period.It is assumed that construction would be keyed to completing the system at the same time that first generating units come on line. Other Transmission Alternatives Service Plans for Anchorage-Cook Inlet Area It must be anticipated that there will be continuing problems and controversy as to bulk transmission facili ties in the approaches to Anchorage.Knik and Turnagain Arms are formidable barriers;the Chugach Range and existing land use designation and ownership patterns combine to restrict alternatives for locating lines.Existing underwater cables across Knik Arm have had serious problems;overhead lines will con tinue to draw opposition;environmental groups would like to see all new lines underwater or underground;this technology has some severe problems in reliability and costs and is particularly vulnerable to extended outage. The transmission alternatives for this area include the following: Addi tional underwater cables and locating cables at different crossing points to reduce hazards of failure. Cables constructed on a Knik or Turnagain causeway.This would eliminate much of the hazard to extended outages since cables would be easily accessible for repairs. Overhead lines around the two arms.One option is rebuilding along the Eklutna transmission right-of-way to provide addi tional capacity . Overhead lines across shallower portions of Knik and Turnagain Arms (place tower structures on piers). Detailed cost estimates for these alternatives were not developed for this study.The same problems will exist with or without the Susitna Project since the available power supply alternatives also require lines crossing or routed around Knik Arm. The basic cost estimates for the proposed plan assume two single circuit lines terminating at Point MacKenzie.An alternative estimate was prepared assuming one line terminating at Point MacKenzie and a second at the existing APA substation at Palmer.Total costs for the two alternatives were similar. It is recognized that the detailed studies following project authorization will need to include careful study in cooperation with the area utilities to determine appropriate facilities in a final plan and that such studies may demonstrate need to include additional capacity to deliver project power to Anchorage.While the plan advanced in this report is not intended as a fixed plan,it is considered an adequate basis for determining merits of the proposed project. Service to Other Railbelt Power Loads The total Railbelt power system will include bulk transmission facilities such as those presented in this report and extensive transn~ission and distribution systems at lower voltage.The bulk power facilities do not replace the need for the distribution systems. For example,the concept of electrifying the Alaska Railroad has been advanced from time to time.This would require power at distribution voltage along the railroad right-of-way.The high voltage lines for the Susitna Project may encourage consideration of Railroad electrification, but a separate line at lower voltage would be needed to serve the railroad. Similarly,the proposal of GVEA to extend its 25 kv distribution line to Mount McKinley Park Headquarters and Cantwell is compatible with the Susitna plan.Again,the high voltage line does not replace the need for the distribution facilities--Susitna power would reach Cantwell through the GVEA distribution system. As a part of the Susitna studies,very rough costs estimates were prepared for transmission lines to deliver Susitna power to Glennallen and other points along the Richardson Highway.These alternatives are discussed in the Power Market Report. Appendix I H-67 SECTION I ENVIRONMENTAL ASSESSMENT FOR TRANSMISSION SYSTEMS UNITED STATES DEPARTlvIENT OF THE INTERIOR Alaska Power Administration Environmental Assessment for Transmission Systems for Devil Canyon and other Potential Units of The Upper Susitna River Project December 1975 -- Contents Title Contents INTRODUCTION DESCRIPTION OF THE PROPOSED ACTION THE CORRIDORS Susitna Corridor Nenana Corridor Del ta Corridor Matanuska Corridor ENVIRONMENTAL ASSESSMENT OF CORRIDORS . SumJIlary Matrixes Susitna-l Nenana-l Susitna-2 Susitna-3 Susitna-4 Nenana-2 Nenana-3 Nenana-4 Nenana-S Matanuska-l Matanuska-2 Delta .... ENVIRONMENTAL IMPACTS OF CORRIDORS . Summary Matrixes .. Susitna-l . Nenana-l Susitna-2 Susitna-3 Susitna-4 Nenana-2 Nenana-3 Nenana-4 Nenana-S Matanuska-l Matanuska-2 Delta ... Comparison of Impacts of Corridors Page No. 1-1 1-4 1-12 1-12 1-15 1-16 1-16 1-21 1-17 1-21 1-22 1-24 1-25 1-25 1-25 1-26 1-26 1-26 1-27 1-28 1-29 1-,')5 1-31 1-35 1-39 1-44 1-47 I-SO I-53 I-56 I-S8 1-60 1-63 1-68 1-72 1-76 MlTIGATTON OF HIPACTS . Soi Is . Vegetation . Wildlife . Existing Developments . Scenic Quality-Recreation '" CuI tural Resources . ADVERSE ENVIRONMENTAL IMPACTS . RELATIONSHIP BETWEEN SHORT-TERM USES OF TIlE ENVIRONMENT ANn LONG-TERM PRODUCTIVITy . If{REVERSIBLE AND IRRETRIEVABLE COMMI'J1I.IENTS OF RESOURCES '"'". OTHER ALTERNATIVES TO THE PROPOSEU ACTION . Sharing of Rights-of-Way . lJnderground Transmission Systems . Direct Current Transmission ..'". Alternative System Plans . Alternative Methods of Construction and Maintenance .. Al ternati ve Endpoints . Alternative Local Service . No Action (non-construction). ACKNOWLEDGHIENTS . BIBLIOGRAPHy . LIST OF TABLES 1-84 1-84 1-87 1-88 1-89 1-89 1-90 1-92 1-96 1-98 1-101 1-101 1-103 1-107 1-108 1-111 1-114 1-116 1-117 1-118 I-J19 Key to Alternative Corridors and Segments 1-14 Corridor Analysis--Project Power to Anchorage/ Cook Inlet..........................................1-77 Corridor Analysis--Project Power to Fairbanks/ Tanana.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-78 Materials and Land Committed..........................1-99 ii - LI S1'OF FIGURES 1.The Railbe1t . 2.Alternative Transmission Line Structures . 3.Alternative Transmission Line Structures '" 4.Alternative System Plans . S.Alternative Transmission Corridors '". 6.Transmission Corridor Segments . LIST OF EXHIBITS I-I Physical and Social Characteristics of the Environment 1-2 Strip Maps Covering the Alternative Corridors 1-3 Photographs 1-4 Glossary iii Page T:2 1-6 1 -7 1-10 1-11 1-13 INTRODUCTION The Transmission System Environmental Assessment for the Upper Susitna Project is one of three reports produced by the Alaska Power Administration as supporting studies for investigations by the U.S.Army Corps of Engineers of hydroelectric development in the Upper Susitna River Basin. The other two APA reports that complement this Assessment are the Transmission System Report and the Power Markets Report.Although there is considerable overlap in these three documents,each of the three discusses basically different facets in the transmission systems. The Corps studies considered several alternative hydro development plans involving four main damsites on the Upper Susitna River above Gold Creek.Four of these sites were identified in previous Bureau of Reclamation investigations (Devil Canyon,Watana,Vee and Denali, as indicated in Figure 1.)The fifth site (High Devil Canyon)is located between Devil Canyon and Watana and is an alternative for developing the head in that reach of the river.Based on engineering,cost,and environmental factors,the Corps proposes an initial development plan including the Watana and Devil Canyon dam and power plants at each site. The transmission system studies for the Upper Susitna River Project are of preauthorization or feasibility grade.They consist of evaluation of alternative corridor locations from the viewpoints of engineering,costs, and environment;reconnaissance studies of transmission systems needed, for alternative project development plans for use in overall project formulation studies;consideration of al ternati ve transmission technologies; and feasibility grade designs and cost estimates for the preferred transmission plan.These studies deal with general corridor location;the more detailed studies following project authorization would include final,on-the-ground route location. The purpose of a preliminary transmission corridor survey is to eliminate those which do not appear to be feasible,whether for technical,economic, or environmental reasons.The preliminary survey then analyzes those remaining corridors and presents the data on the various alternative corridors in such a way so that comparisons can be made.At this point, it is not within the scope of the preliminary survey to show preference for some corridors over others,only to reject obviously unfeasible ones and to analyze the feasible ones.Further analysis then provides the basis for the selection of the preferred system plan. The width of the corridors is variable.In stretches confined by mountain- ous terrain,the corridor may be almost as narrow as the final route;in flat country,the corridor can be several miles wide.Within a given corridor there can be several feasible routes to be selected from in the final route survey. Appendix I I-I ----,-,---- ~s~UNITED STATES DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION RAILBELT 75 A.PA.-JULY 1975 MAP 50 Scale -Mile$. 25- THE Appendix I FIGURE I-I 1-2 Basicall y,the selection of corridors devolves on the need to transmit power from a generation site --the Devil Canyon-Watana dam sites -- to two load centers,Anchorage and Fairbanks (See Figure 1).The load centers are almost equally to the north and south of the LT pper Susitna complex,and are connected to each other by two basic corridors -- the Anchorage-Fairbanks Highway/Alaska Railroad and the Glenn/Richardson Highway.The alternatives are all variations upon these two basic corridors, which are dictated by the topography and climate of the Railbelt area. Although the most economical transmission corridor is theoretically a straight line joining generation site and load center,physical and social factors force deviations from this shortest-distance ideal.Thus,it can often happen that physical and social factors are in opposition to economic factors,and a balance has to be found.This striving for a balance results in alternatives,from which,eventually a most desirable corridor has to be chosen. The method of analysis for the alternatives uses the shortest segments between intersections of al ternati ve corridors as the units of eval uations; these may vary in length from 15 to over 100 miles.These segments were evaluated on a set of physical and social criteria,but are not to be compared to each other.These evaluations are shown in the matrixes on pages 19-22 and pages 34-37. Using these segments as basic units in combination,several alternative corridors can be devised and can then be compared.To save repetition, segments common to alternative corridors being compared can be omitted from the comparison.The corridor presented in the Description of the Proposed Action is that route which produces the minimum adverse impacts consistent with economic feasibility. Appendix I 1-3 Appendix I 1-4 DESCRIPTION OF THE PROPOSED ACTION The proposed action includes the construction and operation of a transmission system to deliver power generated by dams and powerplants on the Upper Susitna to the two primary load centers of Anchorage and Fairbanks,and perhaps other load centers that may prove feasible.The design and location of this line will provide for the most economical construction and reliable operation consistent with minimal damage to the environment. If approved,construction would begin by about 1980. Besides delivery of power from the Upper Susitna Project.another quite important function of the transmission line is the interconnection of the systems presently serving the Anchorage and Fairbanks areas.Inter- connection will have several results.It will provide increased reliability for the entire system in that severe shortage or outages in one utility can then be alleviated by a transfer of power from other utilities.Each utility will need less reserve capacity and surplus from one part of the system can offset deficits in another.Communities presently not served by the larger utilities.or near the fringes of service may benefit from interconnection by tying into the system,thus allowing them to avoid local generation,which is usually a more expensive alternative.Interconnection of the Anchorage and Fairbanks utilities would be a step toward an intertie with Canada and the Lower 48.with benefits on a larger scale than local interconnection. This would lead to the most efficient generation and distribution of energy. resulting in great savings of fossil fuels. The proposed corridor runs from the Devil Canyon powerhouse west to Gold Creek.then southwest along the Susitna River and the Alaska Railroad to Talkeetna.From Talkeetna the corridor follows the east bank of the Susitna River to the Nancy Lake area and then due south to Point MacKenzie.The second half of the corridor runs from Gold Creek north to Chulitna and then parallels the Anchorage-Fairbanks Highway and the Alaska Railroad through Broad Pass,the Nenana Canyon.and to Healy. From Healy the corridor will follow the existing GVEA 138 kv transmission line to the existing substation at Gold Hill to Ester.although the existing right-of-way may not necessarily be used.The section of corridor from Devil Canyon to Point MacKenzie is about 140 miles;from Devil Canyon to Ester is about 200 miles. The proposed facilities are a double circuit 345 kv transmission line to Anchorage.a double circuit 230 kv transmission line to Fairbanks.a switch- yard at each powersite.and the necessary substations to deliver power to the utility systems.Access road suitable for four-wheel drive vehicles will follow the right-of-way where feasible.In areas of highly erodable soils,scenic sensitivity,or vulnerability to impacts stemming from improved access,these access roads will be omitted.This assessment was premised upon stacked double circuits,both circuits using the same set of trans- mission structures.However,reviews by Bonneville Power Administration and other agencies voiced concern for the reliability of this system,and an alternative arrangement of circuits studied. In this arrangement,two single circuit systems parallel each other,not necessarily along the same right-of-way.This parallel single circuit system will reduce the probability of a total break in transmissions,but will cost somewhat more and require more right-of-way and clearing than the stacked double circuit system.The right-of-way for double and single circuits of similar voltage is identical;in the case of 345 kv it is 140 feet,for 230 kv it is 125 feet.A parallel single circuit could require up to twice the right- of-way area and clearing of a single or double circuit. The proposed action will include the alternatives of parallel single circuits and stacked double circuit.Neither system will be exclusive;it is very possible to use both systems along different stretches of the transmission line.In the following discussions of impacts,the acreage of right-of-way and clearing will be premised upon stacked double circuit. The sequence of final routing and construction follows a general sequence of final survey to locate towers and clearing widths,clearing and access construction,erection of towers,stringing,tensioning,and right-of- way restoration. The final survey will involve photogrammetric determination of clearing widths to minimize the amount of clearing;not only is this more economical, but it also avoids the method of total clearing within set distances from the center line.Final tower locations are also determined at this time;tower spacings are usually on the order of four or five per mile,but will be spaced closer as conditions warrant. Towers will be either steel or aluminum and of the free-standing type, although depending upon final design and local conditions,guyed towers may be used in some areas.The conductors are of aluminum conductor reinforced with steel. Appendix I 1-5 "T1:PH"dHCl"d1C:(l)0';>;:1:;3tTl0..~.H><INHSiNGLECIRCUITSINGLECIRCUITFLATCONFIGURATIONDELTACONFIGURATIONFREE-STANDINGTOWERSI•!I•iI.III\:!i-----140'--JT'--IiII:II'00C1>III__J__~---!54'11~1?iSINGLECIRCUITSINGLECIRCUITFLATCONFIGURATIONFLATCONFIGURATIONGUYEDTOWERSTI-~!--1DOUBLECIRCUITSTACKCONFIGURATIONNOTE:STRUCTURESDEPICTEDAREDESIGNEDFOR345KV.230KVSTRUCTURESARESLIGHTLYSMALLER.UNITEDSTATESDEPARTMENTOFTHEINTERIORALASKAPOWERADMIN:STRATIONALTERNATIVETRANSMISSIONLINESTRUCTURESSource'EdisonElectricInstituteA.P.AcJANUARY1975) "00en140'1fol'71Q"0It><TI~56'T-j:.ll----Co....l'T:I;J>H'1:lHCJ'1:lIC('l)-...);:<::l;:lmO-l-"HXIV-lHSINGLECIRCUITDELTACONFIGURATIONGUYEDTOWER"56'rF~IftTHJ<0....SINGLECIRCUITMETALH-FRAMESTRUCTURESource'EdisonElectricInstituteSINGLECIRCUITMETALH-FRAMESTRUCTURE156'~\~Ii)•<0SINGLECIRCUITWOODH-FRAMESTRUCTURESINGLECIRCUITWOODH-FRAMESTRUCTURENOTE'STRUCTURESDEPICTEDAREDESIGNEDFOR345KV.230KVSTRUCTURESARESLIGHTLYSMALLER.UNITEDSTATESDEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONALTERNATIVETRANSMISSIONLINESTRUCTURESA.P.A.-JANUARY1975 Appendix I 1-8 Tower designs will be determined in the final design;val"ying conditions may call for several designs being used.Free standing towers are more easily constructed on sections with good access roads;guyed towers are more suitable for helicopter construction.Various guyed and free- standing tower designs,for single and double circuits,and several alternate structures for use in lieu of these towers in special circumstances are shown on Figures 2 and 3. In heavily forested areas,clearing will be done by brush blades,or rotary cutters on bulldozers and by hand removal of the cleared area and individual danger trees outside of the main cleared strip.Danger trees are those trees that may grown to such a size within five or ten years that they may fall within a set distance from a conductor or tower.Distance from the center line,growth rate,and maximum obtainable height will determine danger trees.Disposal of cleared materials may vary from selling of merchantable timber to chipping or burning of slash. There are known and potential archeological and historical sites along the proposed corridors.To minimize possible vandalism or disturbance,no sites other than those on the National Register shall be located either on a map or on the narrative of this assessment.To preserve the integrity of these known and potential sites,a preconstruction archeological survey of the corridors will be carried out and the final transmission route will be adjusted to minimize disruption.Inadvertent discovery of an unsuspected site at a later stage will entail either the minor relocation of a segment of the transmission line or the salvage of the site as prescribed by Executive Order #11593 and P.L.93-291. In sections where permanent access roads are required,the road will be built and maintained to a standard suitable for four-wheel vehicles. Not all sections will have access roads;in critical areas,winter con- struction,or helicopter construction will be used. Right-of-way restoration after construction includes removal of temporary structures and temporary roads,disposal of slash and refuse and revegeta- tion.In some cases,it may be necessary not only to maintain access roads, but to upgrade them if it is determined by the State Department of Highways that such a road would be a suitable addition to the secondary road system. At each terminus,and at any future taps on the line to serve other communi- ties,a substation will be required.Basically,a substation is required to adjust the voltage supplied by the transmission line to match that of the recipient system.In addition,the substation fulfills a switching function. At the north terminous of Ester,the existing Gold Hill substation could be used with appropriate modification.At the south terminus at Point MacKenzie, the existing underwater cable terminal could be enlarged to accommodate a substation.If an alternative end point near Palmer is finally selected over Point MacKenzie,a substation presently serving the APA US kv Eklutna system could be used. Along some sections,periodic suppression of tall vegetation will be necessary.This will be accomplished with manual application of herbi- cides or hand clearing,or both.Vegetation maintenance will need to be repeated every five years or longer. Periodic inspection of the line will be done from the air,complemented by less frequent inspection from the ground.Inspection will reveal potential failure of tower components such as vibration dampers,insulators, and guy lines;condition of tower footings;condition of conductor;presence of danger trees;and condition of access roads. Alternative methods of construction and maintenance which were referred to above,will be discussed in greater detail in the section Alternatives to the Proposed Action. The preferred system plan was chosen by Alaska Power Administration after preliminary study of all feasible corridors joining the Upper Susitna complex to Anchorage and Fairbanks.The most feasible corridor was selected on the basis of cost,reliability,and potential environmental impact;the remaining corridors represent alternatives of varying degrees of feasibility. Appendix I 1-9 75 100 125 A.P.A.-Morch 1975 DELTA CORRIDOR 230 KV Double Circuit 50 DEVIL CANYON PROJECT ALTERNATIVE SYSTEM PLA NS Scale in miles STATES OEPARTMENT OF THE INTERIOR ALASKA POWER AOMINISTRATION •FAIRBANKS ~345 KV Double Circuit ....... I~MATANUSKA almer CORRIDOR 230 KV Double Circuit H Ieoy NENANA ICORRIDOR Co",w,II_lU-'De.." DevilConyon ~,~r' -"---I Walano ve,e Appendix I FIGURE 1-4 1-10 PROPOSED CORRIDOR_ Ifl.~;i~~'~::-STATES DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION DEVI L CANYON PROJECT ALTERNATIVE TRANSMISSION CORRIDORS Scale in miles 50 75 100 125 A.P.A.-March 1975 Appendix I FIGURE 1-5 1-11 Appendix I I-12 THE CORRIDORS The alternative system plans represent only general corridors,and do not attempt to define an actual right-of-way.Thus the alternatives do not distinguish among many minor variations,and as a result,are fairly flexible. Four alternative dam systems for the Upper Susitna are outlined in the Transmission Systems Report,and two alternative transmission systems to connect them with Anchorage and Fairbanks.Details of the alternative dam systems will be found on Table 1 of the Transmission SystelT's Report. For three of these alternative systems--one of which is the Devil Canyon- Watana System proposed by the Corps of Engineers--the transmission system will consist of the proposed 345 kv double circuit to Anchorage and the 230 kv double circuit to Fairbanks.For the fourth dam system, a 230 kv double circuit to Anchorage and a 230 kv single circuit to Fairbanks will be used. These two alternative designs in conjunction with the alternative transmission corridors,constitute the alternative system plans.The degree of environmental impact is more dependent upon the alternative corridor and,to a lesser degree,upon the voltage;the number of circuits affects environmental impacts least. The width of the corridors is variable.In stretches confined by mountainous terrain,the corridor may be almost as narrow as the final route;in flat country.the corridor can be several miles wide.Within a given corridor,there can be several feasible routes to be selected from the final route survey. There are four groups of alternatives:first,those that lead from Devil Canyon-Watana to Anchorage via the Susitna watershed;second, those that lead to Fairbanks via the Nenana and Tanana drainage;third, those that lead to Fairbanks via the Delta and Tanana drainages;and fourth,those that lead to Anchorage via the Copper and I\1atanuska drainages (see Figures 4 and 5,and Strip Maps in Exhibit I-2). Susitna Corridors There are basically four feasible corridors which connect Devil Canyon to Anchorage via the Susitna drainage.All four of these incorporate the segment that runs from the endpoints of Point MacKenzie to Talkeetna, so this segment can,therefore,be treated as separate and not included in a comparison of the alternati ve corridors. J!!:;~:~~STATES DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION DEVIL CANYON PROJECT TRANSM I SSION CORRIDOR SEGMENTS Scale in miles 50 75 100 125 A.P.A.-March 1975 Appendix I FIGURE 1-6 1-13 Key to Alternative Corridors and Segments Corridor Susitna #1 Susitna #2 Susitna #3 Susitna #4 Matanuska #1 Matanuska #2 Segments of Corridor Susitna Corridors 1,3,7 1,2,7 1,4,5 1,4,6,8 Matanuska Corridors 8,9,20,22 8,9,18,21,22 Nenana Corridors Approximate Total Mileage 136 140 129 147 258 385 Appendix 1 1-14 Nenana #1 7,10,13,16 198 Nenana #2 7,10,12,14,17 220 Nenana #3 7,10,12,14,15,16 231 Nenana #4 8,9,11,14,15,16 223 Nenana #5 8,9,11,14,17 212 Delta Corridor Delta #1 8,9,18,19 280 Of the four corridors that run £l'om Talkeetna to Devil Canyon-VJatana, the first is the southern half of the proposed corridor,which follows the Susitna valley north.paralleling the Alask L1.Railroad to Gold Creek, where it also leads east to tie into Devil C'anyon-Watana (Susitna-l,in Figure 5). The next,and farthest west parallels the Anchorage-Fairbanks Highway through Denali State Park,along Troublesome Creek.eventually leadir..g east to tie into Gold Creek and Devil Canyon-\'Vatana (Susitna-2).The third goes up the Talkeetna River and gaining the ridge to the east of Disappointment Creek,leads north to the ridge leading to Devil Canyon (Susitna-'3). The fourth and most easterly corridor follows the Talkeetna Ri vcr to Prairie Creek.which it follows to Stephan Lake,halfway betvieen Devil Canyon and Watana (Susitna-4). Nenana Corri.dors There are five feasible corridors connecting th~'Upper Susitna with Fairbanks by way of the Nenana River.The first is a corridor paralleling the highway and railroad frorr Gold Creek to Cantwell,to Healy,and to Fairbanks.This is the northern half of the preferred corridor (Nenana- 1,in Figure 5). The second duplicates the first corridor to CanN/ell,but then leads east paralleling the Denali Highway.north up as far as Wells Creek and over the pass to Louis Creek,continuing ever the Dean Creek Pass to the Wood River.It then follows the \!Ilood and Tanana Rivers to Fairbanks (Nenana-2). The third corridor,(Nenana-3),duplicates the second to Dean Creek, where it then continues up Yanert Fork and over Moody Pass,ending up at Healy and joining the firs t corridor. Corridor four (Nenana-4)leaves Watana and heads north.emerging onto the Denali HIghway near the Brushkana River.It then leads west,goes up Wells Creek,and joins corridor three to Healy and Fairbanks. Corridor five starts the same way as corridor four,except that instead of going over 1\100dy Pass to Healy,it leads east over Dean Creek into the Wood River,and then leads north to Fairbanks.(Nenana-5). Appendix I I-IS Appendix I 1-16 Delta Corridor There is only one basically feasible corridor along the I'elta Pi VE~r. This corridor leaves Watana damsite and leads east down Butte Creek to the Denali damsite and continues east along the Denali Highwvy.It then proceeds north near Paxson over Isabel Pass and par<lllels the Richardson Highway into Fairbanks. !l-latanuska Corridors There are two corridors utilizing the Matanuska Valley as access to AnchOl-age.The first follows the Delta route to Paxson.then leads south to Glennallen.It then goes west,over Tahneta Pass,and into the Matanuska Valley,tying into Point MacKenzie. The second corridor connects Watana to Vee dan~site,leads southeast to the Little Nelchina River,which it follows to the Glenn Highway and corridor one,which it follows to Point ~facKerzie. Corridor Segments In order to more easily assess environmental impacts of a transmission line on these corridors,they are reduced to smallf'!"uni is,or corridor segments.A segment is thus that part of a corridor,either between two intersections with other corridors,or beN/pen an intersection and one of the endpoints near Anchorage or Fairbanks.The length of a segment is not standard,nor is the length set by any physical criteria.These segments aTe the minimum number of uni ts that can be combined to form the previously described alternative corridors (see Figure 6). Assessment of the existing environment and of impacts of a transmission corridor will be done on the segment level.As a convenience,these assessments will be summarized in matrix form,differentiated as to environmental inventory and asseSSITJcnt of impacts.The Susitna 2nd Nenana corridors will each have separate matrixes;the Matanuska and Delta corridors will be combined because of the fewer number of alternatives. Segments are labelled in two ways;the first is a nodal label,in which the nodes identify the segment (e.g.Wells Creek-Dean ered:),the second is an assigned number which corresponds to a key map.Both labels arc used on the matrix.Matrixes will be found on pp.18-20 and pp.32-34. Matrixes for Inventory of Corridor Segments: The following matrixes are for inventory of the environment by nine categories.The definitions of the categories and general information are given in the Exhibit 1-L The process from which the 22 corridor segments are derived is explained on pages 15 -20. Due to the problems attendant to reducing such large amounts of information to such a constrained format,it would appear that some of the categories are not treated on the same level of detail as oth~rs.Specifically,climate, which is of greater concern from the design than the environmental stand point,and thus is relatively lightly treated in this Environmental Assessment.Only data that was found by searching the literature was entered.Thus,for example,caribou may be found in a segment although no mention of it is made in the matrix.One advantage to the matrix system of presentation is that it is easily updated;thus,discrepancies brought to our attention can easily be changed. The constraints of this format also oblige the use of abreviations;MMCPM zone stands for the Mount McKinley Cooperative Planning and Management zone,GVEA refers to the Golden Valley Electric Association,MEA refers to the Matanuska Electric Association,and the ARR is the Alaska Railroad. The land status entries are based upon the land status situation of March 1974. State selections refer to not only patented,but also all pending and tentatively approved State selections.Native village deficiencies and regional deficiencies (NVD and NRD)will perhaps be the most unstable areas at present,so it is quite likely that the entries regarding these lands may not be presently valid. Appendix I 1-17 ExhibitI-IThefollowingappendixwilldiscussgeneralcharacteristicsofthephysicalandsocialcategoriesusedintheassessmentoftheproposedcorridorsandtheiralternatives.Bothadefinitionordescriptionofthecategoryandadescriptionofpotentialimpactsinthesecategoriesfromatransmissionlinecorridorwillbediscussed.Notethephase"potentialimpactsII;notallimpactsdescribedwillnecessarilyoccur.Thissectionisintendedonlyforbackgroundinformation;specificandmoredetailedtreatmentoftheproposedcorridorsandtheiralternativesiscoveredunder"EnvironmentalAssessmentofCorridorsIIand"Assess-mentofImpactsII•TopographyandGeologyThisisoneofthemoreimportantcategories,fortopographyinfluencesmostofthesucceedingones.Topographyisitselfasurfaceexpressionofunderlyinggeologyandtectonics(forconvenience,tectonicswillbeconsideredundergeologywhilehydrologywillbecoveredalongwithtopography).TheRailbeltareaischaracterizedbythreelowlandareasseparatedbythreemajormountainareas.TothenorthistheTanana-KuskokwimLowland,whichisdelineatedbytheAlaskaRangetothesouth.TheSusitnaLowlandistothesouthwest,boundedtothenorthbytheAlaskaRange,andtotheeastbytheTalkeetnaandChugachMountains.TheCopperRiverLowlandintheeastisboundedonthenorthbytheAlaskaRange,andthewestbytheTalkeetnaMountains.Eachbasinisunderlainbyquaternaryrockssurfacedwithglacialdebris,alluvium,andeoliandeposits.ThemountainsareprimarilymetamorphicandsedimentaryrocksoftheMesozoic,withseveralareasofintrusivegraniticrocksintheTalkeetnaMountainsandtheAlaskaBange,andI1/esozoicvolcanicrocksintheTalkeetnaWountains.Figure1delineatesthemajorfeatures.TheRailbeltisanactiveseismicarea;the1964earthquakewasperhapsoneoftheniostdestructiveearthquakesonrecord.Theseismichistoryisshortrelativetothetimeoverwhichstrainsaccumulatetoproduceanearthquake,sohistoricseismicityisapoorguidetopotentialseismicrisks.ThereareseveralsignificantlyactivefaultsintheRailbeltarea.Themostspectacularfaultintermsoflengthandprorr:inenceistheDenaliFault,alongarcbisectingtheentireRailbeltthroughtheAlaskaRange.!v1aximumexpectableearthquakesintheareacanbeofatleastamagnitudeof8.5ontheRichterScale.Figure2depictsseismichistoryoftherailbeltfrom1899to1964.I-I LEGEND IGNEOUS ROCKS ""T1 ~. <0c: ""lrn DEPARTMENT OF THE INTERIOR ALASKA POWER AOMINISTRATION GEOLOGY OF THE RAILBELT AREA SCALE~--7 o 50 IOOMllu ( ~ <:;:> glacial debris, MESOZOIC Sandstone and shale;marine and nonmarine; includes some metamorphic rocks PALEOZOIC AND PRECAMBRIAN Sandstone,shale,limestone;mostly marine; includes some early Mesozoic rocks TERTIARY Sandstone,conglomerate,shale,mudstone; nonmarine and marine PALEOZOIC AND PRECAMBRIAN Metamorphic rocks:schist,gneiss,etc.; mainly Paleozoic QUATERNARY Surficial deposits,alluvium, eolian sand and silt Paleozoic volcanic rocks -- Fault (Dashed where inferred) SEDIMENTARY AND METAMORPHIC ROCKS l1li Source:U.S.G.S. APA-1975 El - IIIIIllIIIIl - I~';lA"'1>:1 Paleozoic intrusive rocks;granitic and ultramafic .~Quaternary and Tertiary volcanic rocks ~~~~'-~Mesozoic intrusive rocks;mainly granitic F++++1 Mesozoic volcanic rocks -- H I I\) 1-3Figure2,t""'COROOV~.(~¥u.s.DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONEARTHQUAKES:1899-1964MAGNITUDE~6SOURCE:US.C.s.G.S.1966SCALE~---"0a50100MilesA.P.A.-JULY1975 TheAlaskaRange,withintheareaunderconsideration,ispiercedbytwotributariesoftheTananaRiver,theNenanaandDeltaRivers.Theriverstothenorthoftherangeforthemostpartflowfromglacialsources,throughtherollingnorthernfoothills,andthendirectlynorthtofeedintotheTananaRiver.TheSusitnaRiverstartsfromglacialoriginsquiteclosetothoseoftheNenanaFiver.TheupperSusitnadrainsalargeplateauandfoothillarea,debouchingontoawidefloodplainfromthejunctionwiththeChulitnaandTalkeetnaRivers,thenflowingsouthtoitsmouthinCookInlet.TheGulkanaandNelchinaFiversarebothtributariesoftheCopperPivel'.TheGulkanahasitsglacialoriginsontheAlaskaRange,theNelchinafromglacialandclearwateroriginsintheTalkeetnaandChugachMountains.MostoftheseriversystemsexperiencehighflowsstartinginlateAprilandcontinuingthroughlatesummer.diminishingtominimumsinJ\·IarchorearlyApril.BreakupusuallyprecedesthesnowmeltandoccursinlateAprilorearlyMay.Glacial-fedstreamsaresubjecttoviolentflowandrapidchannelchanges.SoilsSoilsareafunctionofgeology,vegetation,andclinlate.Climate,particularly,playsanimportantroleinsoilformationanddistribution,beingthecauseofoneofthemorewell-knownattributesofnorthernsoils--permafrost.Ingeneral,soilsinboththetaigaandtundraregionareshallowandprofilesarepoorlydeveloped.Slewdecompositionrateslimitthenutrientsupply;insolationislowandtheyearlyaveragesoiltemperatureislow,oftenbdowfreezing.Ingeneral,subarcticbrownforestsoilsdominatenorthoftheAlaskaRange,podzolsdominatesouthoftheRange,andbogandhalf-bogsoilsarefoundeverywhere.Permafrostistheresultofanannualsoiltemperaturenearorbelowfreezing.Technically,permafrostisthatpartofthesoilandbedrockwhichhashadatemperatureof00orlowerforatleasttwoyears.Thus,frozenrockanddrysoilscanbeconsideredtobepermafrost;however,ice-richsoilsaregenerallythetypesofpermafrostofmostconcerntoman-madeprojects.PermafrostisgenerallycontinuousnorthoftheAlaskaRangeandsporadicsouthofit;itsdepthandthicknessvaryconsiderably.1-4 .,',- 2100MII"A.PA.-JANUARY1975o-----~50DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONPERMAFROSTINTHERAILBELTAREA~~.LEI-5MAPUnderlainbyisolatedmassesofpermafrostr-=lLJC-JLEGENDrmmmUnderloinbycontinuouslllllllliIpermafrostf/mUnderlainbydiscontinuous~~;;;~~~~~~~~~~~J~;::=~~~~~~permafrost Thesoilabovethepermafrosttablewhichthawsinsummerisknownastheactivelayer.Sinceice-richpermafrostisrelativelyimpermeable,ashallowactivelayerwilltendtobequitemoist;runoffisslightduetolowevaporationratesandlowsoilpermeability,soevenintherelativelydryinteriorthereisconsiderablesoilmoisture.Theactivelayer,ifoffinegrainmaterial,isverysusceptibletofrostaction,suchasheavesandformationoficelenses.Shallowmoistactivelayersmaybelubricatedduetoexcessivemoistureatthepermafrosttable,resultinginmasswastingonevengentleslopes,calledsolifluction.Thevegetativecoverhasastronginfluenceonpermafrost;therelativelyhighreflectanceofsolarradiation(albedo)limitsinsolation,andtheinsulationprovidedlimitsheattransferfromabove.Otherfactorsinpermafrostdistributionareslopeandaspect,andunderlyingparentmaterial.Duetothewarmermeanannualtemperature,theequilibriumbetweenvegetationandpermafrostcanbemoredelicateintaigathanintundraareas.Forgeneralpermafrostdistribution,seeFigure3.lfostsoilsareofglacialorigin;eitherdirectlyfrommorainalmaterial;orfromglaciolacustrineorglaciofluvialmaterials;orfromloess,orwinddepositedmaterialofglacialorigin.Someoftheseoriginsaree'videntinthecontinuingdepositionofthemajorriversspringingfromtheAlaskaRange.Lowtemperaturesandhighsoilmoisturecombinetocauseslowdecompositionoforganicmaterialandsubsequentlycausetheubiquitiousbogsandmuskeg,typifiedbypeatlayersoverfinegrainmaterial,supportinglittleelsethanblackspruceandsedges.Bogsandmuskegsareespeciallyprevalentinthefloodplainsofriversandlevelareasunderlainbypermafrost.Themajorimpactsofatransmissionlinewillbeasaresultofconstructionactivitiesandofanyaccessroads.Constructionactivities,withtheirpotentialforbreakingthesurfacematofvegetationanddisruptionofsurfacedrainage,canpossiblyresultinwindandwatererosion.Theexistenceandmaintenanceofanaccessroadmaycauseerosion,thoughtoalesserdegreetha.nconstructionactivities.Groundwaterregimeandsurfacedrainagemaybealteredbyanaccessroad,particularlyonfinegrainsoils.Thiscouldresultincreationofbogsonflatlandorgullyingonsideslopes.1-6 Destructionofpermafrostandtheresultantsettlinganderosionmayresultfromincreasedinsolationwherethevegetationmathasbeendestroyed,eitherfromdirectdestructionfromvehicles,orfromover-compactionofwinterroads.Destructionofpermafrostmayalsooccurfromerosionandseverewildfires.Firecontrolproceduresmayresultingreaterdamagetothevegetationcoverthanthatcausedbythefireitself.Otherpotentialresultsfromdestructionofpermafrostareloweringofthewatertablewithanincreaseinthicknessoftheactivelayer,andslopeinstabilitywhichmanifestsitselfasslumpingandsolifluction.Insomelocalareas,thixotropicsoilsexist,whichbecomeplasticunderstresssuchaswouldbecausedbyearthquake.Theintegrityofatransmissionlinecanbethreatenedinthesesituationseitherbyfailureoftowerfoundationsorbyslideorslumps.Wet,finegrainsoilsareparticularlyvulnerabletofrost-heaving,whichcouldcausedamagetotowerfootingsandtheroadway;sinceheavingisaseasonalphenomenon,thismightresultinconstantmaintenanceoftheseareas.VegetationTherearesevengeneralvegetationtypespresentwithinthestudyarea.Theyareclassifiedastothepredominantvegetationtypeandtopographiclocation;thisclassificationisderivedfromthatoftheecosystemclass-ificationoftheJointFederal-StateLandUsePlanningCommission.ThesearedepictedinFigure4;forestdensityinFigure5.Bottomlandspruce-poplarisconfinedtobroadfloodplainsandriverterraces,andwarmersouthslopesofmajorrivers.Characteristicvegetationiswhitespruce,balsampoplar,birchandaspen.Uplandspruce-hardwoodissimilartobottomlandspruce-poplarinthepresenceofthesamecharacteristictrees,butislimitedtothehigherportionsofwatersheds.Actualspeciescompositionvariesduetoslopeande},.rposure.Lowlandspruce-hardwoodisgenerallyfoundonpoorersoilsorsites,suchasonpeat,glacialdeposits,outwashplainsandalluvialfans,oronnorth-facingslopes.Characteristictreesarewhitespruce,blackspruce,tamarack,aspenandbirch.1-7 H I 00 L"gen~ _Coastal Hemiock-Spruce _Bottomland Spruce-Poplar Upland Spruce-Hardwood r··:·\,]Low land Spruce-Hardwood Ii.....i]:~.':<:'<:'::"'<;:High Brush "". IJillID Low Brush,Muskeg-Bog E===========~Moist Tundra I I Alpine Tundra I I Wet Tundra Source:Joint Federal-State Land Use Planning Commission APA -July 1975 "=> DEPARTMENT OF THE INTERIOR ALASKA POWER ADMINISTRATION ECOSYSTEMS BASED ON VEGETATIVE TYPES SCALE~______'7 o SO '00 MIle, "Tl ~. <0 <:., m -"> ~;gure5A.P.A.-JULY1975a50FORESTDENSITYDEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATION1-9MAPSource'AlaskaInternationalRollAndHia'-'YCommission('_DENSEFORESTmnmmMODERATEFORESTlIJI]SPARSEFORESTc::JNON-FORESTey'-///A\\~,.._,I)'-~,)"-\'-\.,.\(I\I Highbushincludestwosub-types.Oneexistsjustabovetimberlineinmountainousareas,theotherexistsonactivefloodplainsofmajorrivers.Characteristicplantsareaspen,balsampoplar,aldersandberries.Lowbush,bog,andmuskegisformedusuallyonoutwashandoldriverterraces,infillingpondsandsloughs,andthroughoutlowlands.Characteristicplantsaretamarack,blackspruce,alders,willows,andberries.110isttundraexistsontherollingfoothillsoftheAlaskaRangeandthehigherportionsoftheupperSusitnaRiver.Characteristicplantsaredwarfwillowsandbirches,Labradortea,greenalder,andberries.Alpinetundratypicallyisfoundinmountainareas,generallyabovetheforestandbrushsystems.Characteristicplantsareresinbirch,Labradortea,mountainheath,rhododendronanddwarfblueberry.Vegetationisafunctionofclimate,soil,topographyandotherfactors,amongwhichisvvildfire.Naturalwildfireshavealwaysbeenanimportantpartoftaiga(borealforest)andtundraecosystems,andvegetationmosaicsareoftenanexpressionofpastwildfires.Manytaigaspeciesshowadaptationstofire;forexample,theconesofblackspruceopenwithheatandthusareamongtheearliestcolonizersofburnt-overareas.Firecanpreventvegetationsystemsfromreachingaclimacticstagebyperiodicdestructionofforest,tothebenefitofsuccessionalvegetation,suchasbrush.Primalproductivityintaigaecosystemsishighestinsuccessionalbrushandlowestinblackspruce,muskegsandbogs.Therefore,agentssuchaswildfireandactivefloodplainscanincreaseandmaintainprimalproductivity.Secondaryeffectsoftheseagentscanbeincreasedforageformammalsanddeepeningoftheactivelayerinpermafrostareas.Mostofthedirectimpactsofatransmissionlineandaccessroaduponvegetationaresmallbecauseoftheinsignificantratiooflandoccupiedbytheline,road,borrowpits,etc.tothesurroundingunaffectedland.Somesecondaryimpactsareofgreaterconsequence.Themostobviousimpactisthelossofvegetation.Thisislimitedtotheaccessroad,andtemporarily,theright-of-way.Primaryproductivitymaybedecreased;inforestedareasitwillprobably1-10 beincreased.Limitedregrowthandmaintenancealongtheright-of-waywillresultinasubclimaxplantcommunityinforestedareas;regrowthinbrushandtundraareaswilleventuallyreachclimaxasfarasnaturalconditionsallow.Inanycase,directchangesinprimaryproductivityalongtheright-of-wayuponthetotalproductivityoftheareaarenegligible.Thereisapotentialforintroductionofnon-nativeorIlweedllspeciesintoclearedareas.However,fewplantsnotalreadyadaptedtotheharshclimate,especiallyofthetundras,willbeabletocompetewiththenativespecies.Whereclearinghasresultedinslashanddebris,thisslashmustbedisposedof.Althoughstackedordispersedslashmayprovidehabitatforsmallanimals,thereisahighpotentialthatslashmayresultinincreasedfirehazardandincreasesininsectpopulationsandpossiblyaffectingsorroundingforests.Slashcanbeburnedintheopen,burnedinforced-draftburners,orchipped.Openburningresultsinconsiderablesmokeandash,yetissimpleanddirect.Forced-draftburningismoreexpensivethanopenburning.Bothburningmethodsaresubjecttoopenburningordinancesofboroughs.Chippingeliminatessmokeandashentirely,butisveryexpensiveandrequiresmoremachinerytotravelalongtheright-of-way.Disposalofthechipsisaproblem,becauseideallytheyshouldbedispersedtopreventkillingtheplantsontheground.Sincedecompositionratesareslow,chipsmaynotreverttohumusforquitesometime.Disposalofchipsinlakesandpondswillresultineutrophicationandcontamination.Slowgrowthrateswillkeepvegetationmanagementalongtheright-of-waytoaminimalmaintenance.Periodiccontrolwillstillbenecessaryinforestareashowever.Mechanicalcontrol,thephysicaldestructionoftrees,canbetimeconsuming,expensive,anddetrimentaltotheright-of-waycover.Theuseofbrushhogsandotherlargemechanizedclearingmachinesisnotonlyinefficient,butalsoentailsdamagetothesoilandsmallplants.Cuttingwillagainraisetheproblemofslashdisposal.Theuseofherbicidestocontrolvegetationintheright-of-wayisconsiderablycheaperthanphysicaldestruction.Herbicidescaneitherbeofabroad-spectrumtypeorspecies-specific;applicationcanbefromtheairorontheright-of-way.I-ll Oversprayanddriftingareproblemswithaerialapplication;applicationonthegroundismuchmoreselectiveandaccurate.Degenerationofherbicidesdependsonthechemicalused,soiltemperature,moisture,texture,andtherateofbiodegradation.Mostherbicidesusedinright-of-waycontrolareoflowto)<.-icitytoanimals,andappeartobenon-cumulative,unlikemanypesticides.Contaminationofla.kesandstreamsispossible;potentialdestructionofaquaticplantsmayresult,destroyingfishhabitat.However,thispossibilityisoffsetbythedecompositionanddilutionofherbicides.Thereislittleornoevidenceoflong-termaccumulationofherbicidesonthesoil;leaching,sunlight,microbialaction,anddegradationbyvegetationitselfinhibitsaccumulation.Physicaldisruptionofthevegetativemat,eitherfromclearingormachinetracks,orfromroadconstruction,willreducetheinsulationoffrozensoilfromsummerwarrrth.Theexposureofdarkersoilwillincreasewarmthfron:insolation;thesefactorscancombinetoalterthepermafrost-vegetationrelationship.Settlingfrompermafrostdestructionwillcauseerosionandthermokarst;loweringofthepermafrosttablewillalterthegroundwaterregime.Theseeffectsinturnwillaffectthevegetationcover.Areaswiththinpermafrost,suchasinthetaiga,areinamoredelicatebalancewithvegetationthanmoreheavilyfrozenareas,particularlyiftheactivelayerisshallowalso.ExperienceinfarmingintheTananaValleyhasshownthatloweringofthepermafrosttableduetodisruptionoftheoriginalvegetationcanalsocauseloweringofthewatertableandsubsequentchangesinvegetationduetoadeeperactivelayeranddryertopsoil.Althoughtaigaecosystemsareadaptedtowildfire,exceptionallydeep-burningfiresinpeatcanchangethepermafrostregimeofanarea,withsubsequentchangeinvegetation.Excessiverepetitionoffiresinanareacanachievethesameresult,andalsocanhavearesultofmaintainingalowsubclimaxvegetation.Secondaryimpactstowildlifearevaried,fromdestructionofhabitatandcovertoenhancedhabitatduetoincreasedprimaryproductivity.Constructionandmaintenanceactivitiesprovideadditionalpotentialforfire;towhatdegreefireswillincreaseisimpossibletopredict.Potentialman-causedfiresdependuponthedistributionandflammabilityofplantcommunitiesalongtheright-of-way,theseasonalscheduleofconstruction,andannualclimaticvariation.Duringconstruction,potentialofman-causedfirewillbegreat,butdetectionshouldbeearly,andareasburnedsmall.Duringoperationandmaintenanceofthetransmissionline,potentialofman-causedfirewillbelow,butdetectionslower,andconsequently,areasburnedwillbelarger.Operationoffire-fightingmachineryofftheaccessroadsmaycauseconsiderabledamage.1-12 Variousplantcommunitiesdifferinrateoffirespreadandresistancetofirecontrol:UplandSpruce-HardwoodLowlandSpruce-HardwoodBottorrJandSpruce-PoplarHighBrushMoistTundraAlpineTundraRateofSpreadHighHighMediumLowMediumHighResistancetoControlMediumHighHighHighMediumLowMan-causedfirepotentialexistsmainlyduringtheperiodofMaythroughSeptember.Uncontrolleduseofaccessroadswillincreasethepotentialforman-causedfires.WildlifeSomegeneralitiescanbedrawnforasthefaunaofthetaigaandtundraecosystems.Themostimportantfactorgoverningwildlifepopulationsanddistributionistherelativelylowprimalproductivityofthetaiga,andtheevenlowerproductivityofthetundra.Herbivore-basedfoodchainsaremoredevelopedanddiverseonthetaigathenthetundra.Inbothareas,arelativelysmallnumberofherbivorespeciesexist,withlessonthetundra.Someherbivoresexperiencecyclicalpopulationfluctuations;thesefluctuationsarecoupledtofluctuationsinpredatorpopulations.Thereishighmobilityofthelargermammalsandbirds.Migratingmammalsareanexpressionofthelowbearingcapacityofthelandforlargeherbivores.Migratingbirdsreflectextremesintheseasonalavailabilityoffood.Sapravory(consumingofdeadplantandanimalmaterial)playsanimportantroleinthefoodchain.Thelownumberofspeciesinthetundraecosystemfoodchainmakesthisanextremelysensitivearea.Adisturbanceaffectingonespecieswillhaveaninordinatesubsequenteffectonotherspeciesinthefoodchain.Anexpressionofthistenuousbalanceisinthefluctuationsinpopulations.Examplesofthesefluctuationsaretheperiodicexplosionsoflimmingandsnowshoeharepopulations,whicharerelatedtothesomewhatmilderandslightlylaggingfluctuationsofpredators,suchaslynxorwolf.Distributionofmoose,bear,Dahlsheep,caribou,bisonandwaterfowlareshowninFigures6, 7,and8.Aquaticecosystemshavesimilarfeaturesoftheaboveterrestrialecosystems.Lowspeciesdiversity,lowgrowthrates,andlonglifespansarecharac-teristicsofthelakefish.Anadromousfishsuchassalmonareextremelyimportantintherailbeltarea;thelowerSusitna,Copper,andTananaRiversarethebasisforaconsiderablecommercial,subsistence,andsportfishery.1-13 Figure6U.S.DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIOf'j100Mn..-2A.P.A.-JULY197!lo50/(,.WILDLIFEMOOSE,DALLSHEEp,BROWNBEAR1-14MAPIIABrown/GrizzlyBearDenningAreas1/:::]MooseConcentrationlIIillII!IDollSheepRongeSource'JoinlFederol-SloleLandU..PlanningCommission Figure7DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONIOO~i1.5A.P.A.-JULY197550SCALEoWILDLIFECARIBOUANDBISON...'...".......~P81f;;t,~;'-"..".:"l...J__.....•..•:~...<.'e.~:.:•....:...•..~...."':.':.....':"..:':."".:.'......:.:.'......"::.:.".;:.:...:","1-15MAP...""-Range~,,~~.""......."....~Co',,'"~nbouSummerRange~:.:.~'::.~'::."",....,~""""~CaribouCalvingRange~,,:~..~'::.~,'''::!loo....l.__or.?,",....,....I11III...."....__BisonRange,~...:i-"'><~_"'77-Source'JointFederal-StoteLondUsePlanningCommission.At.."",.....) Figure8DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONWILDLIFEWATERFOWLHABITATRIlIIIlIllIIIlIHighDensity[[ITTIJ]MediurnDensityITII]LaNDensitySource'Jointfederal-Stat.LaUsePlanningCommission'/I-16SCALE~--........----------o50=100Mile5A.P.A.-JULY1975 Atransmissionlinepersewillnothavemanyimpactsuponwildlife;mostoftheimpactswillbeasaresultofconstructionandmaintenance.Directdestructionwillaffectthelessmobileanimalssuchasthesmallmammals,whoseterritoriesmaybesmallenoughtobeencompassedbytheconstructionarea.Thesignificanceofthisimpactissmallinrelationtotheanimalpopulationinthesurroundingareasunlesstheareaeffectedisakeyareaforaparticularspecies.Theconstructionareawillbereinvadedtoadegreebyanimalsfromthesurroundingareaafterthelineisbuiltandregrowthproceeds.Huntingandtrappingbyconstructionworkerscanbeconsidereddirectdestruction;mortalityfromproject-relatedfirescanalsobeconsidereddirectdestruction.Amoreseriousimpactthandirectdestructionisthepreemptionofhabitat.AnimalsforcedoutoftheirhabitatbyconstructionD1aynotfindanotherniche;thisassumesthatthelandisatitscarryingcapacityforthatspecieswhichisaffected.Someanimals,suchascarnivores,willfleeatalmostallhumanintrusion;iftheyareforcedintoalower-gradearea,oraredislocatedforalongperiod,theywillbeweakenedandincreasedmortalitycanbeexpected.Deliberateorinadvertentharassmentofwildlife,particularlylargemammals,willbeaseriousimpact.Flightstoconstructionsites,maintenanceflights,andoperationofvehiclesonopenareas,allhavethe"potentialforanimalharassment.Harassmentduringcalvingforsheepandcariboucancauseincreasedstillbirth.Althoughatransmissionandaccessroadwillnotimposeabarriertomigrationofcaribou,constructionworkduringcertainseasonsmayinhibitherdsfromapproachingworkareas.Thecreationofaclearedcorridorthroughheavyforestmayresultinincreasedanimalmovementalongtheright-of-way.Migratingbirdsmaysuffersomemortalityfromcollisionswithtowersoflines,buttheselossesshouldbenegligible.Collisionsofbirdswillbemostlikelynearareasofbirdcongregations,suchasrestingorfeedingareas,particularlyduringtimesofpoorvisibilityandduringtakeofforlanding.Thecablesarenotspacedcloseenoughnoraretheyinvisibleenoughtobeefficientsnares.Thesizeofconductorforthe230kvlineis1.4inchesacrossandthespacingis18to40feetbetweencables.Theprobabilityofabirdflyinginanappropriateareaattherightelevationandattheproperangletothelinesimultaneouslyisrathersmall.Electrocutionofbirdsisalsounlikely;thedistancebetweenlinesover115kvandbetweenlinesandgroundisgreatenoughtomakeshortingoutbyabirdalmostimpossible.Birdscansafelyperchoncablesortowers.ThereislittleexperienceofprovenbirdfatalitiesfromcollisionorelectrocutionwiththepresentAPAtransmissionlinesinJuneauandAnchorage.1-17 Themostsignificantimpactsresultfromhabitatmodificationresultingfromimpactsonsoilsandvegetation.Clearinginforestareasandmaintenanceofasubclimaxplantcommunityofbrushandlowplantswillenhancehabitatbyincreasingtheprimaryproductivityoftheclearedarea.Browseformoosewillbeincreased;theconjunctionofgoodcoverintheoriginalforestwithaswathofbrowsecreatesadiverse"edge"habitatformanyanimalsdependentonsubclimaxgrowth.Animalsdependentonclimaxornear-climaxvegetationwillsufferlossofhabitat;examplesaretheredsquirrelandnorthernflyingsquirrel,bothofwhichdependuponWhiteSpruce.Destructionofclimaticlichenontundraareaswilldestroywinterbrowseforcaribou.ThedeclineofthecaribouherdsinP,laskaisattributednotonlytohunting,butalsotodestructionoftundralichenbyman-causedfires.Lichenisthekeybrowseforcaribou,foritistheirprimefoodduringthewinter.Itisestimatedthatapproximately50yearsarerequiredforaburnedareatorecoverausablecoveroflichenforcaribou.Destructionofclimacticvegetationbyfireoftenenhancesmoosehabitat.Tiagaecosystemsareadaptedtowildfire,andpresentmosaicsofvegetationcommunitiesareoftenareflectionofformerfires.Anincreaseoffiresresultingfromman-madecauseswill,uptoapoint,havenotmuchmoreimpactthantheincidenceoflightning-causedfires.Asignificantincreaseovernatural-causedfireswillresultinincreasedmortalityfromfires,excessivedestructionofcoverandhabitatforwildlifedependentuponclimacticornear-cliwacticvegetation,increasedsiltingofriversandlakes,potentialdisruptionofseasonalhabitsandmigrations,andpotentialdisruptionofthepermafrost-vegetationrelationship.Impactuponaquaticlifefromatransmissionlineshouldbesmall.Theaquaticfoodchaininthetaigaandtundraisextremelysimple,andasaresult,disruptionofhabitatforonespeciesquiteoftenindirectlyaffectsmanyotherspecies.Potentialimpactsaretheincreasedsedimentationofriversandlakes;alterationofflows;eutrophicationandpollutionoflakesandstreams;disruptionofhabitatduetogravelborrow,fill,andexcavation;andwithdrawalofwater,especiallyduringwinter.Sedimentationcanresultfromerosionalongtheconstructionsites,burned-overareas,borrowpits,andrivercrossings.Theimpactofsedimentationdependsupontheseverityofsedimentation,theexistingwaterquality,andtheamountofaquaticlifeinthestreamorlake.1-18 Inriversalreadycarryingglacialsediment,theeffectofman-causedsedimentationwillbeslight.Clearwaterstreamsandlakessupportinglargeaquaticpopulationswillbemostaffected.Suspendedsedimentcancausegilldamageinfishandsedimentsettlingoutofsuspensioncanfillinte:rsticesingravelbeds,reducingsuitabilityforspawning.Alterationofdrainagebyanaccessroadmayinfluenceriverflow,butatransmissionlineprojectshouldnotaffectsurfacedrainagetoanyappreciabledegree.Spillsofoilorfuel,herbicides,andotherchemicalsintowaterbodieswillimpactaquatichabitat.Fast-flowingstreamswillbetheleastaffectedbyspills,duetotherapiddispersalanddilutionofthecontaminant;lakesandslowstreamswillbemostaffected.Theactualimpactisdependentuponthetypeofspill,theamount,andthevolumeofwateraffected.Additionofexcessivenutrientsororganicmattertolakes,suchasdisposalofslash,maycauseeutrophication,eitherfromexcessivealgalgrowthorfremdecompositionororganicmaterial.Excessiveoxygendepletioninlakewaterswillleadtofishkills.Alterationofstreamandlakebedswilldestroyhabitat.Someofthealterations,suchasgravelextraction,willaddaninordinateamountofsedimenttoaclearwaterstream.Asecondaryimpactofgreatsignificancetowildlifefromatransmissionlinewillbetheincreasedaccesstoareasnowunservicedbyroads.Ifanaccessroadismaintainedforlinemaintenance,itisverylikelythatitwillbeusedbythepublic.BonnevillePowerAdministrationhasexperiencedunauthorizedpublicuseofthoseaccessroadswhicharesupposedlyclosedtoallnon-maintenanceuse.Tomanymammals,thepresenceofmanhasanimpact,particularlythepresenceofhunters.Increasedaccesstopresentlyinaccessibleareaswillcertainlyaddtohuntingpressuresongamein'tttoseareas.Thedegreeoftheimpactdependsuponregulationbygamemanagementagencies,thequalityoftheareaforhunting,andtheseason.ClimateThiscategoryadherestothedefinitionofclimate,thatis,theaverageweatherconditionsoveralongperiod;however,thereareveryfewclimaticdataforthestudyarea,particularlyinregardstowindspeeds.Thus,eachsegmentisassignedtooneormoreofthreegeneralclirnaticzones.ThesearetheTransitional,Interior,andMountainzones.TheTransitionalZoneisamodifiedcontinentalclimate,havingsomeofthecharacteristicsoftheMaritimeZonealongthecoastoftheGulfofAlaska,yetbeingpartiallysubjecttothegreatertemperatureextremesanddrierclimateoftheInteriorZone.1-19 Theyearlyaveragetemperatureforthiszoneisabout290Finthenortherlypartto380inthesoutherlypart.Temperatureextremesrangefromabout-400to850F.Precipitationrangesfrom12to24inchesperyear;snowfallrangesfromlessthan50tomorethan200inchesperyear.Windsaregenerallycalm,althoughhighwindsover50mphcanbeexpected.TheInteriorZoneisatruecontinentalclimate.Itisrelativelydry,beingdominatedbyhighpressureairmasses.Asaresult,extremeseasonaltemperaturevariationsandrelativelymildwindscanbeexpected.Theyearlyaveragetemperatureforthiszoneisabout240to290F;annualtemperatureextremesrangefrom-600tonearly1000F.Precipitationhasanannualrangeofabout8to16inchesayear.Snowfallamountsfrorr,lessthen50toalmost100inchesayear.Windsaregenerallyverylight,withhighwindsrecordedatlessthan50mph.Sincethisareaisdominatedbystablehighpressureair,temperatureinversionsarecommon,andventilationislow.Thusthepotentialexistsforsmog,fog,andice-fogaroundsourcesofparticulatesand/ormoisture.Ice-fogsrepeatedlycoverFairbanksandseriouslyreducevisibility;thetemperatureusuallymustbebelow-350Fforthistooccur.TheMountainZoneisbasicallyamodificationofamoreprevalentzone,inthiscase,eithertheTransitionalortheInteriorZones.Thecausesofthemodificationareelevationandrelief.Increasedeleva-tiontendstolowertheyearlyaveragetemperaturewithoutdecreasingseasonaltemperaturevariationspresentatlowerelevations.Highreliefcombinedwithelevationresultsinincreasedprecipitationduetoadiabaticcoolingofupliftedairmasses,andanincreaseintheforceoflocalwinds.Sincemountainousterrainisanythingbutuniform,windpatternscanvarytremendously.However,itissafetoassumehighextremesofwindthroughouttheentirezone.LandOwnershipandStatusLandownershipisconsiderablylessinfluencedbyphysicalfactorsandmorebysocialfactors.Atpresent,landownershipisanunstablesituation,foralthoughthemajorityofthelandtraversedbytheroutesegmentsispresentlyFederalland,thatratioisdestinedtochange,withmorelandbeinginStateandNativeownership.WiththeexceptionoftheMatanuskaValleyandthemoreheavilysettledareas,thereispresentlyrelativelylittleprivatelyownedland.1-20 LandStatusisanevenmorechangingsituationthanlandownership.ThepresentlandstatussituationislargelyaresultoftheStatehoodActof1959,ANCSAin1971,andtheAlaskaConservationActof1974.AllFederallandsinAlaskaarepresentlyinawithdrawalstatus;notonlywillaconsiderableportionofFederallandbetransferredtoStateandNativeownership,butalltheremainingFederallandsareslatedeitherforinclusionintoeithertheexistingNationalsystemssuchasNationalParksandtheNationalForests,orforwithdrawalsforclassificationandpublicinterest.Atpresent,apartfromprivateholdings,onlypatentedStatelandandexistingFederalwithdrawalscanbeconsideredconstant.t-lostofthecorridorsegmentslieinlandsthatarependingortentativelyapprovedStateselections,Nativevillagewithdrawals,andNativeregionaldeficiencywithdrawals,allofwhichareinfluxatthepresent.Therefore,assessmentofthelandstatusofasegmentreflectsonlythesituationatthetimeofthispublication.Directimpactsonexistingdevelopmentswillgenerallybelow,mainlybecausetherearesofewexistingdevelopmentsalongthesegments.Duetothechangingnatureoflanduseandownership,impactsmaychangeconsiderablyinthespaceofafewyears.Withthepresentpatternoflandownership,therewillbefewconflictswithlandownership,asmostofthelandalongtheroutesarepresentlyinFederalandStateownership.DistributionoflandstoNativesandotherprivateownersbytheFederalandStategovernmentsinthefuturewillincreasethelikelihoodofpurchaseofeasementofprivatelandsandpossiblesubsequentdisplacementofprivateowners.Littleimpactisexpecteduponexistinglanduse;theright-of-waywidthrequiredforatransmissionlineisasmallfractionofthelandthelinetraverses.Therewillbealmostnoconflictwithagriculturallands;atpresent,agricultureisbasicallylimitedtothelower11atanuskaValley,andsmallerareasintheTananaandCopperRiverValleys.Thepotentialforagriculturee}d.stsoveraconsiderableareaoftherailbelt(seeFigure9),buttheimpactofatransmissionlineonthesepotentialareasislessthanontheexistingareas.ForestryatpresentisverylimitedintheRailbelt,morefromownershipcausesthennaturalcauses.Forestrycanbeexpectedtoincrease,butimpactsfromatransmissionlinewillbeminimal.I-21 Knownandpotentialareasofcoal,oil,naturalgas,andmineralsexistintheRailbeltarea.ThefossilfuelsarepredominantinthethreebasinsoftheTananaRiver,CookInlet,andtheCopperRiverlowland.Mineralsaremoreusuallyfoundinthemoremountainousareas.Atransmissionlineitselfwillhavelittleeffectondevelopmentoftheseresources.TheavailabilityofpowerfromtheUpperSusitnaprojectmightspurdevelopment,butthisisdependentuponthelocalutilitiesandtheirdistributionsystems.LocationofthesemineralresourcesisshowninFigure10,11,and12.Littledirectimpactontownsfromatransmissionlinecanbeexpected;thisresultsfromtheabilitytocircumventthefewtownsencountered.TheendpointsubstationsareoutsideofAnchorageandFairbanks'-sothesetownswillnotbepenetratedbyaright-of-way.SocialImpactsThepredictionofsocialimpactsandtheirmitigationisdifficult;quiteafewvariablesareinvolved,suchasthelaborsupply,thedesiresoftheaffectedcommunities,andtheoccurrenceofotherlargeprojectsintheareaoftheproposedcorridor.However,itiscertainthatbecauseofitssize,therewillbesocialimpactsduetotheconstructionactivity,interconnection,andtheavailabilityofpower.Constructionactivitywillaffectcommunitiesindirectproportiontotheinvolvementandinindirectproportiontotheirsize.Perhapsthebestwaytominimizetheeffectsofconstructionactivityuponsmallcommunitiesiswiththeuseofconstructioncampsspacedalongthecorridor,avoidingthecommunitiesofTalkeetnaandthelowerSusitna,Cantwell,Healy,and Nenana.Thesecampswillbetemporary,tobeconstructedandmaintainedinsuchamannerastominimizedamagetotheirsurroundings.Uponcompletionoftheproject,thecampsshallberemovedandrestoredascloselyaspossibletotheiroriginalconditionorcanbere-usedforotherpurposes.Thespacingofthecampsisdependentuponthenatureoftheterrainandthemethodofconstruction;spacingwillvaryfromfortytoonehundredmiles.Notallcampswillnecessarilyoperatesimultaneously.Theestimatedtimeneededforconstructionisthreeyears;assumingthatthecampsarenotoperatingsimultaneously,butprogressfromonesectiontoanother;thenitfollowsthattheconstructionperiodforagivenareaalongtheproposedcorridorwillbeconsiderablyshortedthanthreeyears.Thus,impactsfromconstructionactivitiescanbeexpectedtolastlessthanthreeyears.1-22 U.S.DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONPOTENTIALARABLELANDINTHERAILBELTAREA,,"'""'.SOURCE:ALASKAINTERNATIONALRAILANDHIGHWAYCOMMISSION1-23Figure9L11ULF1~~LTASCALE~..---==.aa50100Milo,A.P.A-JANUARY1975 aIOOMile.A.P.A.-JULY197!lo_.~~DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONOILANDGASPOTENTIAL1-24MAPSourceJointFederal-StateLandUsePlanningCommission4~~<~"i.L1:..~~--==d/"HighPotentialforOilandGas~ModeratePctential[IT]LowPotential Figure11DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONCOALANDGEOTHERMALAREASMAPlIBCoalAreasmmGeothermalAreasSource'JointFederal-StoteLand_UnPlanningCommissionI1-25SCALEt"""""""\~---..~---o50IOOM,I..A.P.A.-JULY1~7~-~, Figure12DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONPOTENTIALMINERALDEVELOPMENTAREAS100MiinA.P.A.-JULY1975o50.0.....~o. . .PR'f~~;~LlAM......~.~..".:::.,,~..",.-.":..p:,..'>..,""'.. ...,......1-26MAPSource'JointFedertJl-StoteLandusePlanningComminlon_VERYHIGHPOTENTIAtIIIIII!II!HIGHPOTENTIAL Theworkforceisdependentuponthecontractor,thetimeschedule,andtheavailabilityofworkers.Afigurecanbeobtainedasfollows:assumethatworkisprogressingsimultaneouslyalongtheentirecorridor;thatcampsareanaverageofsixtymilesapart,andthatitrequiresfivemenpertowerfortransmissionlineconstruction.Withina60milestretchoflinethereare300towers,andifittakestenworkingdaysontheaveragetoplacea345kvtower,includingfoundations,thenfivecrewscouldcompletethetowersinrangefromcampin60days.Thetimeneededtostringandtensionthestretchwiththreeconductorswillbeanother20days;associatedworkpriortoandfollowingthisconstructionwilloccupytherestoftheseasonofabout15-20weeks.Ifthisrateofworkisprogressingattheothercamps,andifsixcampsareplannedinall,thenatotalof150lineworkersarerequired.Otherworkersareneededsuchasdrivers,pilots,laborers,cementworkers,surveyors,campsupport,andadministration.Thiscouldbringthetotalupto250people;however,actualnumbersmaybeashighastwiceorthreetimestheestimate.Associatedwiththeemploymentgenerateddirectlybythisprojectistheeffectonservicesintherailbeltarea,suchassuppliers,machinerysales,shippers,etc.Theimpactonasmallcommunity.suchasCantwell,willbethatofacampseparatedfromthetown,withabout100-125workersforthespaceofoneortwoworkingseasons;apartfromincidentalcontacts,suchasentertainment,andservicetovisitorstotheproject,thisimpactwillberatherlow,andofshortduration.Operationandmaintenanceimpactswillalsobelow.Arelativelysmallworkforcecanhandleoperationsatthepowersites,substations,andinterveningtransmissionline.MostoperationswilloccuratthepowersitesandtheterminalsubstationsatEsterandPointMacKenzie;amuchsmallerforcecanpatrolthetransmissionperiodically,makingnecessaryrepairsandmaintainingeffectiveclearance.Ifthesmallercommunitiesareserved,theywillrequiretheirownsubstationandcrew,whichcanhandlebothsubstationoperationandlinemaintenancefortheirarea.TheinterconnectionandavailabilityofUpperSusitnapowerwillhavesomeeffects.Forthesmallercommunitiesalongtheproposedcorridor,connectionwiththeinterconnectedsystemwouldprovideelectricpowercheaperthanthepresentlocalgeneration.Manyfamiliespresentlywithoutelectricpowerbecauseofthecostofgeneratorsandfuelwouldfinditmoreeconomicallyavailable.Theavailabilityofpower,not1-27 Figure13••_+__:sA.PA.-JULY197460'80LOCATIONMAP4020oUNITEDSTATESDEPARTMENTOFTHEINTERALASKAPOWERADMINISTRATIONEXISTINGTRANSMISSIONSYSTEMSCOOKINLETAREAX-ll-X-X-X33KVTransmissionLineIt---lt-·-x-·-x69KVTransmissionLinex----x-,--x115KVTransmissionLine~----x----x138KVTransmissionLineScaleinmil~~.._1-28\CHAKACHAMNALAKE---'------."l Figure14(LOCATIONMAP./UNITEDSTATESDEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONEXISTINGTRANSMISSIONSYSTEMSTANANAVALLEYAREA\\X-ll-X-X33KVTransmissionLinex-·-x-·-x69KVTransmissionLine)t---x-··-xI15KVTransmissionLine)t----X-·_-X138KVTransmissionLine4060AP.A.-JULY197420ScaleinmilesoFAIRBANKSAIRPORTWAY1-29 necessarilycheappower,willprobablybeacauseofsomegrowthinthesecommunities.However,itisextremelyunlikelythatindustrywouldbeattractedtooutlyingcommunitiesasaresultoftheavailabilityofpower;thehighcostsoftransportation,laborandmaterialwouldoutweighthebenefitofaccessiblepower.TheprobabilityofdevelopmentofanewStatecapitalalongtheproposedcorridorwouldbeenhancedsomewhatbytheexistenceorpromiseofavailablepowerandaconnectiontothepresentutilitiesintheAnchorageandFairbanksareas.ThelocationofthenewStatecapitalwould,however,beinfluencedmorebytransportation.Inanycase,ifthenewcapitalweretobeconnectedtoUpperSusitnapower,itwouldhaveaprojectedloadoflessthantenpercentofthepresentAnchorageload.Unlikethesmallercommunitiespresentlynotservicedbyoneoftherailbeltutilities,theavailabilityofUpperSusitnapowerwouldnotsignificantlyaffectgrowthinAnchorageorFairbanks.Growthintheseareasisaproblemthatalreadyexists,andincreasedpowerforthesetownsisaresponseto,notacauseofgrowth.Formoreinformationonsocio-economicfactors,seethePowerMarketReport.ExistingRights-of-WayExistingrights-of-wayisconcernedwithsurfacetransmissionandtransportationroutes.Thepossibilityexistsforsharedrights-of-wayorsharedaccesswithanexistingtransmissionortransportationsystem.Someoftheseexistingrights-of-wayarethehighwaysystem,theAlaskaRailroad,transmissioncorridors,theAlyeskaPipeline,andforaproposednaturalgaspipelinesystem.FederallandhasbeenwithdrawnforautilitycorridoralongpartsoftheAlyeskapipelineroute.Thepossibilityexistsnotonlyforsharedright-of-way,butalsofora"symbiotic"useofanexistingright-of-wayinwhichatransmis-sionlinecouldprovidepowerforthepresentoccupant.TwoexamplesareelectrificationoftheAlaskaRailroad,andusingelectricpumpingstationsalongtheAlyeskaPipeline.ExistingtransmissionsystemsareshownonFigures13and14.ScenicQualityScenicqualitydoesnotlenditselfwelltoquantification;thisisamuchmoreambiguouscategorythantheprecedingones,duetothedifficultyindefinitionofsuchtermsas"scenicquality".ThereareseveralI-3D componentsofscenicquality,whichwhendefined,willdefinethiscategory."Existingscenicquality"isastatementofthepresentvisualaspectofanarea,whetheritisanareaofperceivedhighscenicvalue,oranareaoflowscenicvalue.Perceivedscenicvalues(beautiful,ugly,monotonous,vibrant,etc.)areextremelyvariable,notonlybylocation,butalsobyseason,weather,andmostimportantly,bytheindividualviewer.Someofthemoreimportantcomponentsofscenicqualityarescale,unity,intactness,varietyandvividness.Scaleisrelationshipofaviewedareatotheviewer.Scalesrangefromdetail,orclose-upviews,(suchasviewsofsmallelementsofthelandscapeasplants,rockformations,etc.)tomiddleviews,suchasonecouldhaveinaforest,inwhichindividualelementsstillholdmostoftheattention;todistantorscenicviews,inwhichindividualelementsaresubordinatetotheentireview(perceptionofaforestratherthanperceptionofindividualtrees).Unityisthedegreeofharmonyamongelementsinalandscape;putanotherway,itisthedegreeofthelackofdiscordantelements.Awheatfarmoffiveacresisconsideredbymostpeopletobelessdiscordantinanotherwiseforestedlandscapethanafiveacretankfarm.Unityisalearnedconcept,andassuch,isvariablenotonlyamongtheindividualsandgroups,butalsoisvariableovertimeastasteschange.Varietyisthedegreeofdiversityinalandscape;itsconverseisuniform-ity,thedegreeofhomogeneity.Varietymaybeafunctionofscale;alandscapeperceivedasuniform,suchastundra,mayhavedetailviewsofamazingvariety,particularlyinitsplantlife.Thereappearstobenoobviousrelationshipbetweenvarietyandunityorbetweenvarietyandintactness.Vividnessisthestrengthoftheimpressionoflandscape.Itisafunctionofthedegreeofpronouncementofthemajorqualitiesinalandscape.Vividnessisinterrelatedwiththecomponentsofunity,intactness,andvariety.Itdoesnotimplystrongvarietyorstronguniformity,butratherthedegreetowhichvarietyoruniformityisperceivedandremembered.Astwoexamples,thehighlydiverseviewofMt.McKinleyasseenfromWonderLakeandthehighlyuniformlandscapearoundLakeLouisearebothveryvividtotheauthor,whereasthelandscapeoflowerTalkeetnaRiverismuchlessvivid.Sincescenicqualityisacomplexsubject,someassumptionsmustbemadeinordertouseitascategoryinamatrix."Thefirstassumptionisthatwewillonlybeconsideringlarge-scaleviews;detailandmiddle-viewsshouldnotbeaffectedbyatransmissionline.Second,1-31 Figure15NATIONALHISTORICALANDARCHEOLOGICALSITESUS.DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATION(1-32SCALE.,.............~.....---.()50-I.1001.411..A.F'A.-JULY11l7!l MAP([[ll]GoodtoHighQualityScenicAreaB8888JHighQualityScenicAreaSource'JointFederal-StatelAndUsePlonningCommissionI-33Figure16U.S.DEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONSCENICVALUESSCALE~~.....-.~-_.?o50100MII.. noattemptwillbemadetoquantifyscenicqualities;thestudyofperceptionisnotyetadvancedtothepointwhereonecanconfidentlyquantifyasubjectofsuchwidelyvaryingindividualperceptions.Third,theareawithinNationalandStateParksorotherscenicreserveswillautomaticallybeconsideredmoresensitivetoscenicdegradationbecauseoftheirrecognizedscenicqualities.Fourth,landscapesvisablefrommajorsurfacepublictransportationrouteswillbeconsideredmoresensitivethanthosethatarenot.Thereasoningbehindthisisthatallscenicvaluesarenotintrinsictothelandscape,rather,theyareresponsesoftheindividualsperceivingthatlandscape.Anareawithahighnumberofviewercontactswouldthenbemoresensitivetoscenicdegradationthananareawithnoviewers,orwithveryfewviewers.Obtrusivenessisthelackofunityofanelementwiththerestofalandscape,thedegreetowhichanelementisperceivedasincongruous.Atransmis-sionlineinavalleybottomseenfromtwomilesawayislessobtrusiveandvisiblethanalinesilhouettedonaridgeonemileaway.Factorsaffectingobtrusivenessaretowerdesignandheight;designandwidthofclearing;reflectivenessoftowerandcable;topography;anddistancefromviewer.Wherenaturalcoverandtopographyenablealinetobehidden,impactonscenicqualityislow;onopentundra,impactwillbemediumtohigh,dependingondistanceandtopography.Thereareseveralrecreationandscenicreservesaffectedbythealterna-tiveroutes;mostimportantare!\,fountWcKinleyNationalParkandDenaliStatePark.Botharerathersensitiveareas,astheyattractandaretheresultofaconsiderabletouristtrade.ParksinAlaskahavetheimageofopen,unspoiledwilderness,particularlytotouristsfromoutsidetheState.Visibilityofatransmissionlineinoraroundtheseparkswillhaveagreaterimpactthaninotherareas.ThereareavarietyofState-ownedrecreationalareasandwaysidesadjacenttothehighwaysintheRailbelt;impactontheserecreationalsiteswillbelow;duetotheirrelativelysmallsize,theycanbecircumventedeasily.TheNationalRegisterofFebruary4,1975listssixregisteredhistoricalandarchaeologicalsitesthatmightpossiblybeaffectedbythealternativeroutes.TheseareshownonFigure15.ThereareknownandpotentialarcheologicalandhistoricalsitesnotontheNationalRegisteralongtheproposedcorridors.TominimizepossiblevandalismordisturbancenositesotherthanthoseontheNationalRegistershallbelocatedeitheronamaporonthenarrative1-34 ofthisassessment.Topreservetheintegrityofknownandpotentialsites,apre-constructionarcheologicalsurveyofthecorridorswillbecarriedout,andthefinaltransmissionroutewillbeadjustedtominimizedisruption.Inadvertentdiscoveryofanunsuspectedsiteatalaterstagewillentaileithertheminorrelocationofasegmentofthetransmissionline,orthesalvageofthesitesasprescribedbyExecutiveOrder11593andP.L.93-291.Thealternativeroutescrossnoproposedorexistingscenic,wildorrecreationalrivers,nordotheycrossanyproposedorexistingwilder-nessareasorwildliferefuges.However,insegmentswherethetrans-missionlinewillpioneeracorridorthroughapreviouslyintactarea,thequalityofwilderness\villsuffer,especiallyifthetransmissionlineiseasilyvisible.However,inmostsegmentsthetransmissionlinewillparallelexistingcorridorsorwilltraversenosignificantlylargeareasofintactwilderness.Apioneercorridorcrossingasignificant-lylargewildernessareawillhaveahighimpactonaccessandfuturelocationofotherrights-of-way.Theseinturnwilldegradewildernessqualityfurther,buttothebenefitofincreasedaccessforrecreationalusesinvolvingmotorizedaccess.Figure16showsanapproximationofexistingscenicquality.HazardsandInconvenienceOneofthemoreobviouspotentialhazardsisthatofelectricalshock.Threedistincthazardscanbedefined.Oneisthebriefvoltagebrieflyappearingonthegroundnearadroppedconductor.Thesecondisthedirectcontactwithaconductor.Thethirdhazardisthatofinducedcurrentinmetallicobjectsnearanoperatingtransmissionline.Whenaconductorisdropped,eitherasaresultoftowerorconductorfailure,itisswitchedoffinafractionofasecond.Duringthisshorttime.avoltageiscausedintheimmediatevicinityofthecontact;thehazardwouldvarywiththedistancetothecontactpoint,thevoltageproduced,andotherfactors.Droppedconductorsarearareeventinmosttransmissionsystems;theyaretheresultofvandalism(riflefire),storms,andoccasionally,defectsofcomponents.Directcontactcanbealethalhazard;usuallyitinvolvesinadvertentlyshortingoneoftheconductorswithmachineryorotherequipmentworkingunderatransmissionline.Constructionbooms,pipes,andpolesmustbemaneuveredwithcarenearanoperatingtransmissionline.Sincegroundclearanceincreaseswithoperatingvoltage,thishazardislesswiththehighervoltages.1-35 Itispossibletoinduceavoltageinmetallicconductorsparallelingatransmissionline,suchasraillinesandfences.Thiscouldpresentapotentialhazarddependentupontheconductivityandlengthoftheobject,anditsdistancefromthetransmissionline.Propergroundingofpotentialinductingobjectswilleliminatethishazard.Overheadtransmissionsystemsnearairfieldsandareasofheavylow-flyingairtrafficpresentapotentialhazardtoaircraft.Properplacementandroutingwillreducethishazard;theuseoftaut-spanshorttowerscanreducetheheightofanoverheadsystem,andmarkingconductorsthatspanvalleysandnotcheswillincreasevisibilitytoaircraft.Anoperatingoverheadtransmissionsystemwillgenerateaudiblenoiseimmediatelyadjacent,particularlyifthevoltageis345kvorhigher.Fora345kvline,audiblenoiseattheedgeoftheright-of-waywillbelessthan45decibels,roughlyequivalenttothenoiseleveloflighttrafficat100feet.Actualaudiblenoiselevelsarerelatedtovoltage,configuration,andheightofconductors,atmosphericconditions,andindi'vidualsensitivity.RadioandtelevisionreceptionimmediatelyadjacenttoanoverheadtransmissionsystemmaysufferfromelectromagneticinterferenceCEtI.lI).Suchinterferenceislocalized,andismoreintenseduringrain.OtherfactorsinfluencinglevelsofEMIarethevoltageandconfigur-ationoftheconductors,heightofconductoraboveground,ageandsurfacefinishofconductor,andatmosphericconditions.AgoodreferenceforEM!andaudiblenoiseistheEHVTransmissionLineReferenceBook.Evidenceofeffectsonlifefromexposuretoelectricalfieldspresentinthevicinityoftransmissionlinesisinconclusive.SeveraltestscitedintheBattelleReport"MeasuringtheSocialAttitudesandAestheticandEconomicConsiderationsWhichInfluenceTransmissionLineRouting"indicatenoilleffectsnotedonlinemenworkinginverystrongelectricalfields,andmiceexposedtoelectricalfields;however,othersourcesintheUSSRandGermanycitedbythisreportindicatedpossibleharmfuleffectsonanimalsandhumans.OzoneproductionbyCoronalossesfromtransmissionlinesislow.TheBattelleReportcitedaboveindicatesthatozoneconcentrationadjacenttoa765kvlinewasontheorderofonly2to3partsperbillionbyvolume;thisconcentrationshouldbeconsiderablylessfor230kvlines.1-36 STRIPMAPSCOVERINGTHEALTERNATIVECORRIDORSAPPENDIXIEXHIBITI-2 Exhibit1-2StripMapscoveringtheAlternativeCorridors.Thefollowingstripmapsareinthreegroups:thoseshowingthegeneralfeatures.thosedepictinglandstatus.andthosedelineatingsoiltypes.Thealternativecorridorsarecoveredbysevenmapsforeachgroup;thereissomeoverlapfrommaptomap.butnotallalternativecorridorsareentirelydepictedonanyonemap.Oneachmapisagraystripeshowingtheapproximatepositionofanalternativecorridoronthatmap;thesepositionsareveryapproximate.andtheexactlocationandwidthareindeterminate.ThelandstatusmappedisbaseduponthelandstatussituationofMarch1974.Stateselectionsincludepatented.pending.andtentativelyapprovedState-selectedlands.Duetothepresentunstableconditionoflandstatus.itmustberecognizedthattheremaybechangessincethedateofthemap.Thesoilsmapsarebaseduponthe1:250.000soilsoverlaymappublishedbytheJointFederal-StateLandUsePlanningCommission. .i\JN·iT~·DSTATESDEPARTMENTOFTHEINTERIORALASKAPOWERADMINISTRATIONINDEXTOALTERNATIVECORRIDORMAPSScaleinmiles5075100125A.P.A-March1975 A.P.A.-March/97525201015Scaleinmileso5ANCHORAGE-DEVILCANYON )~~~~0~2.--t.--.:...-..JI_L-!./-.....~~~~o I~----o5Scaleinmiles101520I25A.P.A.-Morch1975SUSITNA \\'\\\)J1\;, 252015CANTWELL-PAXSONAP.A.-March197510Scaleinmileso5RANGE7 ) BLAIRLAKEAIRFORCERANGE-------~--;20251015ScaleinmiIe.~_KARIV£R~~"-1' Scaleinmiles1510I~~~'_RIVERMOUNTMCKINLEY4- ScaleinmilesFORTGREELY~-­o5101520 '.MILITARYBLAIRLAKEAIRFORCERANGEFORTGREELY i25201015VALDEZ-RScaleinmiles-----5o (f)2:-<:{I-2.::>o~.:z:o<:{<.9.::>.:z:oe;~~:::..~~~~~~~~9,q,7oc.,o /)1-~,/r"\\IIScaleinmiI~s101520.125oD -,252010.milesScaleIn_15/','".,-'<./".'-\\)MOUNTINS\<EETNA1AL SOILSLEGENDSoil"~_mmCi})..SlopeGroup-~I(------I~TexturalGroupSoilsErosionPotentialEAT-Poorlydrainedsoils,normallyinwaterlaidmaterials.EFT-Welldrainedsoils,instratifiedmaterialsonfloodplainsandlowterraces.EOL-Welldrainedgraysoils;shallowbedrock.EOP-Welldrainedloamyorgravellygraysoils;deeppermafrosttable.HMT-Poorlydrainedpartiallydecomposedpeat;seldomfreezesinwinter.HMV-Poorlydrainedpartiallydecomposedpeat;containslensesofvolcanicash.HY(B)G-Poorlydrainedfibrouspeat;freezesinwinter.HYP-Poorlydrainedfibrouspeat;shallowpermafrosttable.IAHP-Poorlydrainedsoilswithpeatysurfacelayer;shallowpermafrosttable.lAP-Poorlydrainedsoils;shallowtodeeppermafrosttable.lAW-Moderatelywelltopoorlydrainedsoils;maycontaindeeplyburiedicemasses.ICF-Welldrainedbrownsoils;containslensesoffine-grainmaterial.ICP-Welldrainedthingrownsoils;deeppermafrosttable.ICT-Welldrainedgrownsoils;non-acid.IND-Welldraineddarksoilsformedinfinevolcanicash.IUE-Welldrainedsoilswithdark,acidsurfacelayer.IUL-Welldrainedsoilswithdark,acidsurfacelayer;shallowbedrock.IUP-Welldrainedthinsoilswithdarkacidsurface;deeppermafrosttable.RM-Verysteep,rocky,orice-coveredland.SOP-Welldrained,thin,stronglyacidsoils;deeppermafrosttable.SOT-Welldrainedstronglyacidsoils.SOU-Welldrained,stronglyacidsoils;verydarksubsoil.Themappingunits,whilereferringtoonlyoneortwodominantsoilsintheassociation,includeothersoilsandlessextensivesoils.SlopeGroups1 -Slopesdominatelylessthan12%.2 -Slopesdominatelysteeperthan12%.TexturalGroupsc -sandyf -clayeyErosionPotentialg -verygravellym -loamy(medium)E-l-lowE-2-mediumE-3-high RM§QY-HY(B)G2mE-2~-HY(B)G1mE-I,2SOU2gE-I,2 §Q!-HY(B)G2gE-2RM'1M>/~.Hr.lVSOUE·22mE-2grr-HY(B)G1mE-I,2~o SOPIAHPE-220-"'1m1015Scaleinmiles5\\~~~-RM)i)!\;, /0\\~UL_RM)29I;1\; RM20r-_.::.2::::.,5-~-10 15A.PA.-Morcll1975501LS~CANTWELL-PAXSONRANGE_IAHP1m:-27 !YJ:-RM20E-I/2LL__~---I._--I.t:::.~-.......-ALA Scaleinmiles~_1AHf2g1m101520 lkI_lAHf2g1mScaleinmiles/1RM1015(\2 ScaleinmilesRM1520RM10,....",.---o5RMlAW_leTE-21mIQ ICTIAHPE-210-2mICF_IAHPE-232m1m•IAHPE_21mICT-IAHPE-2.32g1mICFIAHP2m-1m'3LJ-.JU--L-L..---l.__--L-_~___.llI.._I_-) 1510SOILS:VALDEZ-R~,,"n5oW~E~2If/:)~E-2CFIfD!AHfE-21mIUPE-32gIA1:LPE-2IfP-IAHP2g)E-2,3 RMRMRM~~~IUP-IAHP2gE-2,3IAHPE.1m:.:::.:::::::::;::;:;:.-:.:.:-::::::.:.:.:.:.:.:.:.:lAJiPE-2If IUP-IAHP2QE-25RMScaleinmiles10152025RMoDIAHPIfE-2SOILS:PALMER-GLENNALLEN IUP-IAHP2gE-2ScaleinmilesRMRMRMRMSOU-IUL2gE-I/51--'---=O5=--__1:0~_~15::.......____=2~O__..:2~·~_ :'/':.~~"k>~}"..:.~'.'...l...',...,....·.f.',.......'...,1.:','.:LANDSTATUSLEGENDMajorwithdrawalspriortoAlaskaNativeClaimsSettlementAct,(December18,1971)WithdrawalsforpossibleinclusiononthefourNationalsystems(D-2)Withdrawalsforclassificationandpublicinterest(D-l)Stateselections-patented,tentativelyapproved,andpending(SS)WithdrawalsforNativevillageseligibleforlandselectionsWithdrawalsforNativevillages,eligibilityforlandselectionnotfinallydeterminedVillagedeficiencywithdrawals(NVD)oRegionaldeficiencywithdrawals(NRD)~~~~~~;~;~~Utilitycorridor(UGlThesemapsrepresentthelandstatussituationasdeterminedbytheBureauofLandManagement,December18,1973 ...)55101520250-2A.~A.-March1975LANDSTATUS:ANCHORAGE-DEVILCANYON /61-----1._55 2010.15Scaleinmiles_~----o5•..•.•.........."Q.10· 55\\\\IJ1\)Nf ScaleinmilesNRDSATUSCANTWELL-PAXSON55252015APA.-MorCh197510=I""""I..WW_-LANDo555RANGE~55 /9-----l._--L.~A Lt SUSITNACORRIDORSINVENTORYCLIMATEEXISTINGDEVELOPMENTSLANDOWNERSHIP/STATUSEXISTINGRIGHTS-OF-WAYSCENICQUALITY/RECREATIONbear,Varioussmalltownsalongtrans-PrimarilyStatepotentialse1-Recreationareas:BigLake,RockyTransitional-milderandwetterportationcorridor.Severalections;indetenninate(asofAnchorage-FairbanksHighwayLake(SUckerLake),NancyLake,Ginsouthernendofsegment.recreationareasandcampgrounds3 -74)NativevillagesofMontanaAlaskaRailroad,MEAlines.'WillowCreek.Mediumtolowalonghighway.Creek,Caswell,andWk.scenicqualityinsouth.Mediumy.tohigharoundTalkeetna.•blackTransitional/mountain.Stateselectedland.DenaliStateP~ra11e1~Anchorage-FairbanksRunsthroughDenaliStatePark.None.Park.Highwaymmidsection.Highscenicquality.TownsofGoldCreek.Curry.Lane.ParallelseastboundaryofDenaliearers.Transitional.Chase.andSherman.MostareStateselectedland,bordersonParallelsA.R.R.smallcommunitiesJnotallDenaliStatePark.StatePark.servedbyAlaskaRailroad.bearers.Transitional.Stateselectedland.None.Mediumscenicvalue,relativelyNone.accessiblebyboat.andgrizzlyMountain/traP$itiona1.None.1/3.State~e1ectedland,2/3Highscenicqualityarea-re1a-1ge.Nat~vereglOna1deficiency.None.tive1yinaccessible.bears.1/3Stateselectedland2/3SomerecreationaluseoflakesinMountain/transitional.None.Nativeregionaldeficie~cy.None.PrairieCreekPassarea.Highscenicquality-accessiblebyfloatp1aile.None.1/2Stateselections1/2NativeH~ghscenicquality-impressiveTransitional.r~v~rvalley.Limitedaccessi-regionaldeficiency.'None.b~hty.bear,Mountain/transitional.Nativeregionaldeficiency,power-Highscenicquality-limitedNone.sitewithdrawalforDenaliCanyonNone.accessibility.Reservoir.iIbear,Mountain.Nativeregionaldeficiency,power-Recreotiona1useofFogLakesNone.None.area.Highscenicquality-sitewithdrawalforDenaliCanyonaccessiblebyfloatplane.Reservoir.CIICITt\!1\ SUSITNACORRIDORSINVENTORYTOPOGRAPHY/GEOLOGYSOILSVEGETATIONWILDLIFECLIMATETransitional/mountain.Transitional-milderand~insouthernendofsegment,MooseeverywhereJblackbearJfurbearers.TrumpeterSwanhabitatinpondsalongSusitnaValley,Cariboumightbepresent,blackbear,moose.Bottomlandspruce-poplar,uplandspruce-hardwood,lowbrushmus-keg/bog.Alpinetundra(?).Bottomlandspruce-poplar,lowlandspruce-hardwood,muskeg/bog.GlacialdebrIs-groundmorinnealteredbyoutwash,floodplains,silt,sand,gravel,swampsandlakes,Freefrompermafrost.Poorlydrainedfibrouspeatsoils,otherpoorlydrainedsoilsandwelldrainedstronglyacidsoils,r,owtomediumerosionR"'o"'te"'n"'t"'i"'al"','-+-i,.--1-_Innorthernpart,welldrainedthinsoils,stronglyacid;deeppermafrosttable,Southernpartpoorlydrainedfibrouspeat,otherpoorlydrainedsoilsandwelldrainedstronglyacidsoils,Slopesonnorth),12%.Lowtomediumerosionpotential.84miles.Highestpoint500'atTalkeetnatosealevelatPt.McKenzie.Widerivervalley;eastbankmorerollingthanex-tremelyflatwestbank.Valleywidensandflattenstosouth.Poorlydrained,manybogsandlakes.42miles.Rollinghighplateautonorth,becomingflatter,lower,forestedhillstosouth.MergesintoSusitnaValley.Highpointaround2000f •PointMacKenzie-TalkeetnaTalkeetna-GoldCreekviaTroublesomeCreek(2)Talkeetna-GoldCreekviaAlaskaRailroad(3)38miles.Highpoint900'.Veecanyon-moderatelynarrowvalleyfloorwideningtothesouth.Welldrained,gravelly,stronglyacidsoils.Southernthird,poorlY,drained,fibrouspeatandwelldrained,stronglyacidsoil.Slopesonnorth>12%.Lowtomediumerosionpotential.Bottomlandspruce-poplar,uplandspruce-hardwood.M:lose,blackbear,furbearers.Transitional.TalkeetnaRiver(4)8mi~es.500'elevation.Wide,:r:ollmgvalleybottom.Manylakes.Poorlydrainedfibrouspeat,vulnerabletoheavingandwelldrained,stronglyacidsoils.Slopes<12%.Lowtomediumerosionpotential.Bottomlandspruce-poplar.~bose,blackbear,furbearers.Transitional.DisappointmentCreek(5)37miles.3800'elevation.Rollinghillsincreaseineleva-tiontohighplateauwithseveralincisedcreeks.Welldrained,stronglyacidsoilsthininnorthernpartsincon~junctionwithverysteepandrockyground.Gravellysoil.Slopes>12%.Lowerosionpotential.Bottomlandspruce-poplar,uplandspruce-hardwood,lowbrush,mus-keg/bogandalpinetundra.~boseinlowerelevationsandstreambottoms,blackandgriZZlybear,possiblecaribourange.Mountain/transitional.PrairieCreek-StephanLake(6)42miles.2200'elevation.Widevalleynarrowsgraduallyasitrisestowide,flat,poorlydrainedpass.Welldrained,stronglyacid,gravellysoils.Slopes>12%.Lowtomediumerosionpotential.Bottomlandspruce-poplar,uplandspruce-hardwood,lowbrushmus-keg/boginpassarea.'~bose.blackandgrizzlybears.Mountain/transitional.DevilCanyon-GoldCreek(7)14miles.1500'elevationabovedamsite.Narrowcanyonincisedinplateauwidensasplateauchangestorollinghillstowest.Welldrained,stronglyacid,gravellysoils.Slopes>12%.Lowtomediumerosionpotential.Uplandspruce-hardwpod.~bose,blackbear.Transitional.13miles..2200'elevation.HighDevilCanyon-StephanplateaumthdeeplyincisedcreeksLake(8)andrivers.Welldrained,stronglyacid,gravellysoils.Slopes>12%.Lowtomediumerosionpotential.Uplandspruce-hardwoodinriverandstreamvalleys,lowbrushandbog/muskegonplateaus.M:lose,blackandgrizzlybear,furbearers.Mountain/transitional.17miles.2200'elevation.FlatStephanLake-Watanaplateauboundedbyhillstonorth(9)andsouth,incisedriverandcreeksWelldrained,thin,stronglyacidsoilswithdeeppermafrosttableandpoorlydrainedsoilswith'shallowtodeeppermafrosttable.Gravellysoils.Slopes<12%.Mediumerosionpotential.Uplandspruce-hardwoodinriverandcreeks,brushandbogandmus-kegonplateau.~bose,blackandgrizzlybear,furbearers,caribou.M:luntain. WILDLIFENENANACORRIDORSINVENTORYCLIMATEEXISTINGDEVELOPMENTSLANDOWNERSHIP/STATUSEXISTINGRIGHTS-OF-WAYSCENICQUALITY/RECREATIONespeciallyinlowerMountain/transition.SeveralsmallcommunitiesalongHighscenicqualityalongmostof>oplar,up-~bosepresent,Sunmitweath-thisroute,southernpartborders.owbrush-valleys,blackbearonforesteder:annualtemperature25.9F.,transportationlines.FAAstripsStateselectedland,Nativevillage~An~horage-FairbanksHighway,AlaskaDenaliStatePark.Majorviewstoareas.annualprecipitation21.85"•atSt.UI1lllitandCantwell.Southern\;ithdrawal,areawithin~MCPMZone.Ra11road.\;estandnorthoftransportationpartbordersDenaliStatePark.corridorofAlaskaRange.10l;landCaribouconcentrations,moosein~~diumscenicqualitybutinacces-lowervalleysandplateaus,Dall~buntain.None.V-Iwithdrawal,northernpartwith-None.sible.csh-muskegsheepinhighareas,blackbearonin~t>lCPMZone.forestedareas.irdwood.Caribouconcentrations,moosepre-DenaliHighway,somesettlementNativeVillagewithdrawal,StateDenaliHighway.Highscenicqualitygoodviewstosent,Dallsheepinhighareas,Mountain.blackbearinforestedarea.alonghighway.selectedland,withinMMCPMZone.allsides.'Mountain.HighwindsreportedbySeveralsmallcommunities.Mc-Highscenicquality,impressived,lowlandCaribouconcentrationssouthofGVEAtohaveknockeddown138KVKinleyParkonwestbankofNenanacanyonsinterspersedwithopennetundra,canyons,moosepresentinmoretowers.McKinleyweather:annualRiver.FlightstripsofYanertStateselectedlandandMcKinleyAnchorage-FairbanksH1ghway,Alaskaareasofmoredistantviews.Goodmuskeg.openpartsofcanyons,Dallsheeptemperature27.7F.,annualprecip-and~kKinleyVillageandHealyNationalPark,withinH\cfCPMZone.'Railroad.possibilityofviewingwildlife.inhighareas,blackbearpresent.itation14.50".(FAAatMcKinley).Hightouristtrafficalongthismajortransportationcorridor.,uplandCaribouconcentrations,mooseinJSh-muskeg/lowerelevations,DallsheepinMountain.None.D-landStateselectedland,WellsNone.Highst:enicqualitybutinacces-Highbrushhighareas,blackbearinforestedCreek,rithinMMCFNZone.sible.area,iSTizzlybearinhigherareas.I,uplandCaribouconcentrations,mooseinush-mus-lowerelevations,DallsheepinNoneinmountains'UsibelliCoal~~diumscenicqualitybutinacces-alpinehighareas,blackbearinforestedMountain.MinesatHealy.'Stateselectedland.None.sible.,werMoodyareas,grizzlybearinhigherareas.ir,uplandCaribouconcentrationsonwestldspruce-bankofNenanabetweenHealyandSmallcommunitiesalongtransporta-PrimarilyState-selectedlandwithHighscenicqualitynearHealyandrRlSkeg/bog,southofClearAFB.moosealongInterior.Healyweather:annualtionlines.Severalflightstrips.someexistingFederalwithdrawalsAn~horage-FairbanksHighway,AlaskatheC,oldstreamHills.Lowtomed-~s,northwholeroute,blackbearinforestedtemperature26.4°1'.,annualpre-FAA.stationatNenana.TownofandNativevillagewithdrawals.Ra11road,GVEA138kv.line.iumscenicqualityalonglowerlce-hard-Nenana,ClearMilitaryReservation.uplandareas.TrumpeterSwanhabitatcipitation11.34",NenanaRiver.DryCreekArcheo-alongpondsofTananaValley.logicalSite(NationalRegister).Caribouconcentrationsinuppersh,lowWoodRiver,moosepresentinlowerPr~arilyStateselectedland.)isttundra,elevationsandstreambottoms,DallNone.Scenic.qualityrangesfromhigh,lowersheeponhighareasofupperWoodMountainandinterior.BlairLake~lilitaryReservation.Na~lv7villagedeficiencyandtomed1umbutinaccessible.lterspersedRiver,blackandgrizzlybeareX1st1ngFederalwithdrawals.ldswith~patterns.present.TrumpeterSwanhabitatalongpondsofTananaValley.NENANAINVENTORY TOPOGRAPHY/GEOLOGYSOILSVEGETATIONWILDLIFENENANACORRIDORSINVENTORYCLIMATE48miles.2400'elevation.WideWelldrained,thin,stronglyacidvalleywithmoderatelyincisedsoils,deeppennafrosttableandBottomlandspruceandpoplar,up-Moosepresent,especiallyinlmverMountain/transition.SumnitGoldCreek-Cantwellriversinsouth,becomingverypoorlydrainedwithsurfacepeatlandspruce-hardwood,lowbrush-valleys,blackbearonforesteder:annualtemperature25.9(10)widedepressioninBroadPass,andshallowpennafrosttable.bog/muskeg.areas.annualprecipitation21.85".travelingNE,withrollingvalleyBothsoilsgravellywithmediumbottom.erosionpotential.Slopes<12%.Onslopes>12%:Welldrainedthin46miles.3300'atDeadmanPass.stronglyacidsoilswithdeepper-Caribouconcentrations,mooseinmafrosttable,gravelly.OnslopesUplandspruce-hardwood,lowlandWatana-WellsCreekviaSeriesofmoderatelywidevalleys<12%:Poorlydrainedloamysoilsspruce-hardl;ood,lowbrush-muskeglowervalleysandplateaus,DallMountain.joinedbygentlepasses,culminat-sheepinhighareas,blackbearonBrushkanaCreek(11)ingonwidevalleyofBrushkanawithsurfacepeatandshallowper-bog.Alpinetundra.forestedareas.mafrosttable.~1ediumerosionpo-CreekandNenanaRiver.tential.22miles.2500'elevation.Welldrained,thin,stronglyacidValleysoilswithdeeppennafrosttableWellsCreek-Cantwellq.tWellsCreekwidenstowest,withinconjunctionwithpoorlydrainedLowlandspruce-hardwood.Caribouconcentrations,moosepre-flatbottomboundbymountainstosoilswithsurfacepeatandshallowsent,Dallsheepinhighareas,Mountain.(12)northandsouth.pennafrosttable.~1ediumerosionblackbearinforestedarea.potential.Gravellysoils.Slopes<12%.39miles.2200'atCantwell.Widevalleynarrmvstonorthtoseri~s,WelldrainednonacidbrolvngravelMountain.Highwindsreport'oftightcanyonsseparatedbymdesoilsinconjunctionwithpoorly'Uplandspruce-hardl;ood,lm;landCaribouconcentrationssouthofGVEAtohaveknockeddown13Cantwell-Healy(13)valleyofYamertFork.Northofdrainedloamysoilwithsurfacespruce-hardwood,alpinetundra,canyons,moosepresentinmoretowers.McKinleyweather:;canyontoHealyiswiderollingpeatandshallowpennafrosttable.somelowbrush-bog/muskeg.openpartsofcanyons,Dallsheeptemperature27.7F.,annual]plainwithstreamterracesadjacentHigherosionpotential.Thinrockyinhighareas,blackbearpresent.itation14.50".toNenana.Denalifaultcrossesasoilsandrockonlowercanyon.Windy.26miles.4,000'atWellsPass.Lowlandspruce-hardlvood,uplandWidevalleynarrowingtothenorthCaribouconcentrations,mooseinWellsCreek-DeantopasswithLouisCreek,ahighThinsoilsandrock,verysteepspruce-hardlvood,lowbrush-muskeg/lowerelevations,DallsheepinMountain.Creek(14)saddle.AbruptdropintoLouisslopes.Levelareaspoorlybog,andalpinetundra.Highbrushhighareas,blackbearinforestedCreek,downtoYanertForkanddrained.inYanertValley.area,¥Tizzlybearinhigherareas.extremelywideaggradingchannel.Thinrockysoilsandrock,steepCaribouconcentrations,moosein24miles.2700'atMoodyPass.slopesonupperparts.SteepLowlandspruce-hardlVood,upland.Northupwidevalleyandoverwidegravellypoorlydrainedsoilswithspruce-hardlVood,lowbrush-mus-lmverelevations,DallsheepinMountain.DeanCreek-Healy(15)flatpassintosinuousv-canyon,variablepennafrosttableincon-keg/bog(inpassarea),alpinehighareas,blackbearinforesteddroppingintowidervalleyofHealyjunctionwithsteepgravellywelltundra(ridgesalonglowerMoodyareas,grizzlybearinhigherCreek.drainedgraysoils,shallowbed-Creek).areas.rock.~bderateerosionpotential.97miles.1400'atHealy.350'atHealy-Nenana:Well-drainedbrmvnBottomlandspruce-poplar,uplandNenana,1500'inGoldstreamHills.gravelsoilsandpoorlydrainedCaribouconcentrationsonwestWide,terracedvalleyofNenanaloamswithsurfacepeat,shallowspruce-hardlvood,lowlandspruce-bankofNenanabetweenHealyandflolVsnorthtomergewithTananapennafrosttable.Nenana-Ester:hardlvood,lmvbrush-muskeg/bog,southofClearAFB,moosealongInterior.Healyweather:HealytoEster(16)floodplain.OverTananaRiverwell-drainedbrownloamswithlevelareastendtobogs,northwholeroute,blackbearinforestedtemperature26.4°F.,annuallensesoffinesandpoorlydrainedslopesarelOWlandspruce-hard-trendingN.E.arelowrollinghillsloamswithsurfacepeat,shallowwood,sunnyslopesareuplandareas.TrumpeterSwanhabitatcipitation11.34"ActivefaultatHealy.Ice-richalongpondsofTananaValley.clayandsiltat~body.pennafrosttable.~diumtohighspruce-hardwood.Ip...n~;nn.110miles.4300'atDean-WoodPassUpperWoodRiver:ThinrockysoilsAlpinetundra,highbrush,lowCaribouconcentrationsinupperDeanCreek,sharpmountainvalleyLowerWoodRiver:PoorlydrainedWoodRiver,moosepresentinlowerJ:>eadsinhighpassintoWoodRiver,loamysoilswithsurfacepeatandbrushbogandmuskeg,moisttundra,elevationsandstreambottomsJDallDeanCreek.toEsteriu-shapedglaciervalleywithag-shallowpermafrosttable.Gentlelmvlandspruce-hardwood,lmversheeponhighareasofupperWoodMountainandinterim:(WoodRiver)(17)gradingstream,whicheventuallyslopes.SomewelldrainedbrownWoodRiverisareaofinterspersedRiver.blackandgrizzlybeardebouchesontoTananafloodplain,bogsandleveesandmoundswithnonacidsoils.Lowtomediumcorrespondingvegetativepatterns.present.TrumpeterSwanhabitatflatandpoorlydrained.erosionpotential.alongpondsofTananaValley. DELTAANDMATANUSKACORRIDORSINVENTORYl;uplandushbogl.vetypes-poplarrood;low'g;moistlowbrushlowbrush,pruce-lice-poplarWILDLIFENelchinacaribouherd(presentlyabout4000-5000),moosepresentinmoderatelyhighnumbers,blackandgrizzlybears,wolvespresent.TrumpeterSwanhabitatalongpondsofTananaValley.BigDeltabisonherdfallrange(200animals),DallsheepcommononAlaskaRange,blackandgrizzlybears,goodduckhabitatinsloughsandoxbowsofChenaandSalchaRiversandmorainalpondsofDonnellyDome.Peregrinefalconhabitat,particularlynearSalchaR.Nelchinacaribouherd,mooseinmoderatelyhighnumbers,blackandgriZZlybears,wolvespresent.'NelchinacaribouandveryhighmooseconcentrationsonGulkanadrainage,blackandgrizzlybears,wolvespresent,goodduckhabitatalongGulkanafromSummitandPaxsonLakes,ThawLakes.GulkanaismostimportantfisheryinCopperRiversystem.PaxsonandSummitLakesareimportantfishlakes.~bosepresent,blacl<andgriZZlybear,Dallsheeponsurrotmdingmotmtains.CLIMATE~btmtain.Interior.~tmtain/interior.Interior.Transition/motmtain.EXISTINGDEVELOPMENTSNone.Lowtonopotentialforcommercialforestingandagri-cultureduetosoils.ConsiderablesettlementalonghighwaynearFairbanks.Militarybases,townsofBigDeltaandDeltaJtmction,potentialagri-cultureatBigDelta-ClearwaterLake.None.Lowtonopotentialforcommercialforestryoragricul-'ureduetosoils.TownsofGlennallen,Gulkana,settlementalonghighway.Recrea-tionaldevelopmentnorthofGlennHighway.Thisareahaslowpotentialforcommercialforestryandagricultureduetosoils.ConsiderabledevelopmentinMata-nuskaValley.CoaldepositsnearSutton.Farminginlowervalley,recreationusealongKnikAnn.LANDOWNERSHIP/STATUSStateselectionsJNativeregionaldeficiencywithdrawals,andD-1withdrawals.DenailDamsitewith-drawal.AreaaroundDenaliDamsiteiswithinMMcPMZ.Stateselections,utilitycorridorandmilitaryreservations.Nativeregionaldeficiencyandstateselections.WatanaandVeepowersitewithdrawals.StateselectionsandUtilityCorridor.Nativevillagewith-drawalsofGulkana,Gakona,TazlinaandCopperCenter.Stateselectionsprimarily.SomeNativeregionaldeficiencyandD-llands.Nativevillagewith-drawalsofChickaloon,EklutnaandKnik.EXISTINGRIGHTS-OF-WAYDenaliHighway.RichardsonHighway,AlyeskaPipeline.None.RichardsonHighway,AlyeskaPipe-line,GlennHighway.GlennHighway,AlaskaRailroad,variousminorroads.SCENICQUALITY/RECREATIONTangleLakesArcheologicalDis-trict(NationalRegister).DenaliCampgrotmd.TangleRiverBoatLatmch.Highscenicquality-easilyaccessiblewithgoodviewstonorthofMt.HayessectionofAlaskaRange,Clean~aterandAmphitheater~untains.ProposedHistoricalSites:RapidsHuntingLodge,Mile220;BigDeltaRoadhouse,Mile252.Clearwater,Donnelly,FieldingLake,WaysideParks.DeltaCampgrotmd,proposedDeltaWildRiver.Excellentviel'sofAlaskaRangefromBigDeltasouth.Easilyaccessible.ToeastisLakeLouiserecreationallandcomplex.Highscenicquality-landoflakesandponds.Access-iblebydirtroadfromGlennHigh-.waytoLakeLouiseorbyfloat:plane.SourdoughLodge(NationalRegister)ProposedhistoricalsitesofMc-Creary'sRoadhouse,Mile104;GakonaRoadhouse,Mile132;Pax-sonLakeWaysidePark;SourdoughCampgrotmd,DryCreekWayside,LittleNelchina,TolsonaandLakeLouiseWaysides.ProposedPaxsonLakeRecreationAreaandGulkanaWildRiver.Hightomediumscenicquality.KnikArcheologicalSite-IndependenceMinesnearPalmer(NationalRegister).BigLake/RockyLakeWaysides.ChugachStateParktosouth.MatanuskaValleyishighscenicqualityarea.Severalscenicoverlooksalonghighway.Highlyvividlandscape.DELTA/MATANUSKAINVENTORY DELTAANDMATANUSKACORlINVENTORYWatanatoPaxsonviaButteCreek(18)PaxsontoFairbanks(19)WatanatoSlideMtn.viaVee(20)PaxsontoSlideMtn.viaG;ennallen(21)SlideMts.toPointMacKenzie(22)TOPOGRAPHY/GEOLOGY98miles.4000'nearRockCreek.Variesfromwide,flat,openter-raintorolling,post-glacialterrain.Valleyfloorsareusuallywideandflat,poorlydrained.Manylakes,kettles,andmorainalridgeseasttoMac-larenRiver.Thisuplandareacontainsaltiplanationterracesandisunderlainwithdiscon-tinuouspermafrost.152miles.2700'atPaxson,3000'atIsabelPass.RollinghillsatPaxsonleadtohighflatpassandnorthtoU-shapeMountainValleynearRainbowRidge-BlackRapidsarea.RollinghillsnearDon-nellyDomedecreasetoflatlandbyEielsonAFB.90miles.3000'elevationatplateauatheadofLittleNelchinaRiver.Generallyflatandrollingterrain;ahighplateauextendingfromSusitnRivertoLakeLouisearea.Numeroslakesandbogs.119miles.2700'atPaxson.Rollinghillsandflatplateaus,cutbyincisedstreams.Poorlydrained,havingmanylakesandbogs.138miles.3000'atTahnetaPass.Widepassapproachedfromeastbe-comesnarrowvalleytowestofpass.Incisedriverandlowridgesoccupyvalleyboundedbyinajormountainrangesonnorthandsouth.Valleydeboucheson-toMatanuska-Knikfloodplain,toPt.McKenzie,routecrossesmanylakesonflatfloodplainsandpoorlydraineduplands.SOILSLowareas:poorlydrainedsoilswithsurfacepeatandshallowpermafrosttable.Texturesrangefromgravellytofine.Slopes:Well-drained,thin,stronglyacidsoils;deeppermafrosttable.Mediumtohigherosionpotential.Lowareas:Poorlydrainedsoilswithsurfacepeatandshallowpermafrosttable.Slopes:Welldrainedsoils;somecontaininglensesoffines.Shal-lowtodeeppermafrosttable"ifany.Mediumerosionpotential.RockysoilandbedrockinDeltaCanyonarea.ThixotropicsiltsjustnorthofSum-mitLake.PermafrostcontinuousfromShawCreektoTananaRiver.Lowareas:Poorlydrainedsoilswithpeatysurface;shallowper-mafrosttable.Mediumerosionpotential.Uplands:Welldrainedthinsoilswithdarkacidsurface;deeppermafrosttable.Gravellytexture.Med-iumerosionpotential.Perma-frostiscontinuousonthispoorlydrained,ice-richareaoffinesediments.Majorportionofroute:Poorlydrained,finegrainsoilswithsurfacepeat;shallowpermafrosttable.Mediumerosionpotential.Uplandareas:Welldrained,thin,stronglyacidsoilswithdeeppermafrosttable.Perma-frostiscontinuousinthisarea.MatanuskaValley:Welldrainedloamyorgravellygraysoilsandstronglyacidsoils.Mediumtohigherosionpotential.KnikAnn:Poorlydrainedfibrouspeat,vulnerabletofrostheaving,andwelldrainedacidsoils.Lowtomediumerosionpotential.VEGETATIONLowlandspruce-hardwood;uplandspruce-hardwood,lowbrushbogandmuskegmoisttundra.Fullrangeofvegetativetypesfrombottomlandspruce-poplartoalpinetundra.Uplandspruce-hardwood;lowbrushbogandmuskeg;moisttundra.Lowlandspruce-hardwood,lowbrushbogandmuskeg.Lowlandspruce-hardwood,lowbrushbogandmuskeg;uplandspruce-hardwood;Bottomlandspruce-poplaragriCUlturalland.WILDLIFENelchinacaribouherd(presentlyabout4000-5000).moosepresentinmoderatelyhighnumbers,blackandgrizzlybears,wolvespresent.TrumpeterSwanhabitatalongpondsofTananaValley.BigDeltabisonherdfallrange(200animals),DallsheepcommononAlaskaRange,blackandgrizzlybears,goodduckhabitatinsloughsandoxbowsofChenaandSalchaRiversandmorainalpondsofDonnellyDome.Peregrinefalconhabitat,particularlynearSalchaR.Nelchinacaribouherd,mooseinmoderatelyhighnumbers,blackandgriZZlybears,wolvespresent.'NelchinacaribouandveryhighmooseconcentrationsonGulkanadrainage,blackandgrizzlybears,wolvespresent,goodduckhabitatalongGulkanafromSummitandPaxsonLakes.ThawLakes.GulkanaismostimportantfisheryinCopperRiversystem.PaxsonandSummitLakesareimportantfishlakes.~osepresent,blackandgrizzlybear,J?allsheeponsurroundingmounta1.IlS.CLIMATE~buntain.Interior.~untain/interior.Interior.Transition/mountain. SOILSVEGETATIONSUSITNACORRIDORSIMPACTSWILDLIFEEXISTINGDEVELOPMENTSSCENICQUALITY/RECREATIONConsiderableclearingisneeded.Uplandvege-Destructionofhabitatforsmallanimals.En-Littleimpactonscen1CqualityfromNancytoPt.I-tKenziesincelinecanbeconcealed.,ilvulnerabletofrostheavingbuttationwillwarrantmaintenance;poorlydrainedhancementofhabitatforlargermammalsduetoSomepossibleconflictswithprivatelandsfromPossibleconflictwithrecreationareasinrosionpotentia}.Uplandsoilsareareaswillprobablyneedlittlemaintenance.increasedsuccessionalgrowth.HarrassrnentNancyLaketoTalkeetna.Noimpactonfore-Wasilla-BigLakeareaandNancyLakearea,'ptibletoerosion.Thermaldis-Slashmustbedisposedoftoinhibitinfestationunlikelyduetogoodcoverthroughoutarea.seeableagriculture-mostsoilsareunsuit-dependinguponfinallocation.Noconflictunlikely.NomajorrivercrossingsofremainingtreeswithsprucebeetleoripsFromNancyLaketoPt.McKenzie.accesswillableforagriculture.withKnikarcheologicalsite.Talkeetnaatedonthisroute.beetle.Vegetationhashighresistancetofirebeimprovedifaccessroadleftin;increasedtoNancy:linecanbealmosttotallycon-control.huntingpressuremayresult.cealedorlaidparallelandadjacenttoexistinglineclearings.problemsinherenttosoilsaroundLowerelevationforestwillneedconsiderableFrostheaving,possiblepermafrost,ge,slowrevegetation.Uplandclearing;regrowthratefastenoughtowarrantHighimpactonscenicquality-invadesDenalielldrained,buterosionpotentialmaintenance.UplandareaswillrequirelessRouteopensupaninaccessibleareawithin~';oneStatePark.Linecanbeconcealedsomewhat,Possiblerivercrossingneededforclearingandmaintenance.EXceptforareaDenaliStatePark;closedtohunting.butwillundoubtedlyinterferewithpotentialCreek,threeneededforSusitnaabovetimberline,vegetationhasahighratetrailusers.naRivers.Accessroadcrossing.onofspreadoffireandahighresistancetoCreekmaycausesiltation..control.Treeclearingneededalongentiresegment;NoextensiveinaccessibleareasopenedupIflineadjoinsAlaskaRailroad,railroadmaintenancewillbeneeded.VegetationhaslineparallelsA.R.R.;accessroadwouldMediumimpactonscenicquality.Mosttraffic,Riveronlymajorrivercrossing;highrateofspreadandhighresistancetoallowvehiclestoreachthisareaindepen-couldbeelectrifiedandcorridorconsolidated.throughthisstretchisbyA.R.R.,andlinelereisnotaproblemasrivercarries·control.Brushwillbeintroducedbyre-dentlyfromtheA.R.R.,sohuntingpressureIncreasedaccesstoanareapresentlyhavingcanbewellhiddenfrompassengersusingItalready.growth.mayincrease.IftheA.R.R.right-of-wayisonlyafewflagstopsonAlaskaRailroad.raillinesunlesscorridorisconsolidated.adjournedorshared,impactswillbeverylow.eainedsoilssusceptibletofrostExpensiveclearingofheavyforestneededPioneerroutewillopenupnewareastoaccess.LowimpactOnscenicquality.Lineisnotmdpoorfoundations:welldrainedwithmaintenance.BrushwillbeintroducedHuntingpressurewillincrease.Brushintro-,.visible.Wildernessqualitysomewhat~\:Jne;lopeslessapttocauseproblems.byregrowth.Vegetationhashighrateofductioninthisareawillenhancehabitatsimpacted,buteaseofconcealmentkeepsediumerosionpotential.LittlefirespreadandhighresistancetocontrOl;formoose,bear.impactlow.:lofseriouspermafrostdegradation.Clearingandmaintenanceneedinlowereleva-degradationoflocalpermafrost.Fewtions.Mostofrouteishighlandspruce-PioneerroutewillopenupconsiderablenewLinewillcrossopenalpinetundraforquitea)leimpactsfromerosion.siltation,orhardwoodandalpinetoodra.Preservationofareastoaccess.Mostofthisareaisopendistance,havinghighimpactonwildernessqual'.grooodvegetationessential-disruptioncanforesttoalpinetundra-damagetohabitatIbnetty.stdegradation.resultinlonglivedscarscluetoslowregrowthcouldbesevere(fromfires,erosion.ORV's).rate.Upperelevationshavehighrateoffirespread,lowresistancetocontrol.HeavyforestclearingneededonTalkeetnaPioneerroutewillopenupconsiderablenewWherelineemergesfromTalkeetnaRivervalleyRivervalleywithintroductionofbrushrequir-areastoaccess.ImpactwillbelessonPrivatelandand/orcabinleasesonlakeshoresupperareasduetolessdisruptionofvege-toStephenLake,scenicqualityreceivesmediUJ1~eableimpactsfromerosion.siltationiogmaintenance.Lessclearingrequiredandinthepassareas.~jostofthesecanbeimpact;lakesreceivedsomerecreationaluse.morecareforvegetativematneededinPrairietationbyclearing.Areaispresentlyac-avoided.OtheTh'ise,noimpactsonexistingImpactonwildernessismediumduetothecostdegradation.cessiblebyfloatplaneandreceivedcon-CreekvalleytoStephenLake.Hightomediumsiderablehuntingpressurealready.developments.existingrecreationaluseandeasyaccessihil-rateoffirespreadJhightomediumresistanceitybyfloatplane.tocontrol.MooseandbearhabitatenhancedbyregrowthOldjeeproadexists,connectingDevilLowimpactonscenicquality-thisareaisClearingofmediumforestwithperiodicmain-CanyonDamsitetoAlaskaRailroad.Miningnotpresentlyeasilyaccessible,andDevilCan-eeableimpactsfromerosionJsiltationtenance.Highrateoffirespread,mediumre-onclearings.Accessroadmayresultinclaims,nolongeroperating,onPortageyonDamsiteroad1Yillnotbeusedmuchbynon-rostdegradation.sistancetocontrol.increasedhuntingpressure.Creek.Theseroadscouldbepartoftheprojectpersonnel;linecanbeconcealedfromaccessroadsystem.thisroadorcanbeusedasthelineaccessroadalso.:Clearingofmediumforestinrivervalley;Littleimpactonhabitatoflargemammalssuchlessclearingneededonplateau.Firerateasmooseandbear,minimalclearingonplateauLowimpactonscenicquality-areaisofmed-eeableimpactsfromerosion,siltationofspreadinvalleyhigh,resistancetocontrolareasandcreekcanyonscanbespanned.Ac-Noneiumscenicquality.Somerecreationalusein>:ostdegradation.medium.Onplateau,rateoffirespreadlow•.cessroadwouldbeundercontrolfromdam-StephenLakearea.Linecanbepartiallycon-resistancetocontrolhigh.sitesounauthorizeduseforhunting,,"'Quld\cp.aledbutnottotally.be1m;.Heaviervegetatio:1increekbottomscanbeLittleimpactonhabitatofmooseandbear,Mediumimpactonscenicquality-areaiso~onimpactsbutpossiblepermafrost·spannedoverbyline.Vegetationonplateauminimalclearingonplateauareasandspan-mediumscenicquality.SomerecreationalInandfrostheavinginpoorlydoesnotrequireextensivecleaning.Rateofningofcreekcanyons.Accesswouldbe!t!:'meuseofStephenLakearea.Linecanbepar-undercontrolofdamsitessounauthorizedJils.firespreadlow.resistancetocontrolhigh.useforhootingwouldbelow.tiallyconcealedbutnottotally.l"1I~I"'~IA SOILSVEGETATIONConsiderableclearingisneeded.UplarLowlandsoilvulnerabletofrostheavingbuttationwillwarrantmaintenance;poorlyPoint~\I:acKenzie-withlowerosionpotentia}.Uplandsoilsareareaswillprobablyneedlittlemaintena"moresusceptibletoerosion.Thermaldis-SlashmustbedisposedoftoinhibitinfeTalkeetnaruptionisunlikely.Nomajorrivercrossingsofremainingtreeswithsprucebeetle01:areanticipatedonthisroute.beetle.Vegetationhashighresistancecontrol.SomedesignproblemsinherenttosoilsaroundLowerelevationforestwillneedconsiTalkeetna:Frostheaving,possiblepennafrost,poordrainage,slowrevegetation.Uplandclearing;regrowthratefastenoughtoTalkeetna-GoldCreeksoilsarewelldrained,buterosionpotentialmaintenance.UplandareaswillrequirviaTroublesomeCreekishigher.Possiblerivercrossingneededforclearingandmaintenance.EXceptfor(2)TroublesomeCreek,threeneededforSusitnaabovetimberline,vegetationhasahigandTalkeetnaRivers.Accessroadcrossing,onofspreadoffireandahighresistancTroublesomeCreekmavcausesiltation."control.Treeclearingneededalongentirese&TalkeetnaRiveronlymajorrivercrossing;maintenancewillbeneeded.VegetatiTalkeetna-GoldCreekhighrateofspreadandhighresistarviaAlaskaRailroad(3)siltationhereisnotaproblemasrivercarries-control.Brushwillbeintroducedbyglacialsiltalready.growth.PoorlydrainedsoilssusceptibletofrostExpensiveclearingofheavyforestruheavingandpoorfoundations;welldrainedwithmaintenance.Brushwillbeint:TalkeetnaRiver(4)soilsonslopeslessapttocauseproblems.byregrowth.VegetationhashighraLowtomediumerosionpotential.LittlefirespreadandhighresistancetoCIlikelihoodofseriouspermafrostdegradation.ClearingandmaintenanceneedinlowerPossibledegradationoflocalpermafrost.Fewtions.Mostofrouteishighlandspruhardwoodandalpinetundra.Preservat,)isappointmentCreekforeseeableimpactsfromerosion,siltation,or.groundvegetationessential-disrupti(5)permafrostdegradation.resultinlonglivedscarsduetoslowrate.Upperelevationshavehighratespread,lowresistancetocontrol.HeavyforestclearingneededonTalkeeRivervalleywithintroductionofbrushPrairieCreek-StephanFewforeseeableimpactsfromerosion,siltationingmaintenance.Lessclearingrequir<Lake(Liorpermafrostdegradation.morecareforvegetativematneededinCreekvalleytoStephenLake.Hightorateoffirespread,hightomediumrestocontrol.De,';'lCanyon-GoldFewforeseeableimpactsfromerosion,siltationClearingofmediumforestwithperiodiCreek(7)tenance.Highrateoffirespread,I1l€orpermafrostdegradation.sistancetocontrol.4Clearingofmediumforestinrivervall.lessclearingneededonplateau.FireDe,';'lCanyon-StephanFewforeseeableimpactsfromerosion~siltationofspreadinvalleyhigh,resistancetoLake(8)orpermafrostdegradation.medium.Onplateau,rateoffirespre,resistancetocontrolhigh.Heaviervegetatio':1increekbottomsccStephanLake-WatanaFewerosionimpactsbutpossiblepermafrost-spannedoverbyline.VegetationonI(9)degradationandfrostheavinginpoorlydoesnotrequireextensivecleaning.drainedsoils.firespreadlow,resistancetocontrol SOILSVEGETATIONNENANACORRIDORSIMPACTSWILDLIFEEXISTINGDEVELOPMENTSSCENICQUALITY/RECREATIONSuccessivelylessclearingassegmentgoesEntiresegmentwithinMt.McKinleyCoopera-north.InBroadPass,notreesneedSomeenhancementofbearandmoosehabitatpactislow.Shallowpermafrostinclearingandtheonlyvegetationlostinsouthernpartofsegment;nochangeinFewprivateholdings-smallchanceofcon-tivePlanningandManagementZone.Southerninedareassusceptibletodegrada-wouldbefromaccessroad.Slowregrowthnorthernpart.Thisrouteopensupno'flict.Lowimpact-veryfewexistingpartbordersDenaliStatePark.Visibleline~theaccessroadcanavoidtheseimpliesthatmaintenancewillnotbeneededmajornewareastohunting;overallimpactdevelopments.willhavehighimpact,particularlyiftowestofhighwayandrailroad.Linecanbecon-iimpactwillbelow.andalsothatrevegetationmaybenecessaryisl~'!.cealedsomewhat,however,inmostofsegment.alongsomeareas.MediumtohighrateofBroadPasshasleastcoverforline.firespread;highresistancetocontrol.Clearingvariesfromdensespruce-hardwoodsSomeenhancementofbearandmoosehabitattoalpinetundra.~bstvegetation1055inheavierforestedareas,butnosignifi-Lowimpactonscenicquality;thisareaistinedloam:impactonpermafrostinwillbefromaccessroad.Slowregrowthcantchange.Accessroadopensupapre-ofmediumscenicqualityandnotreadilyshigh,andfrostheavingisposs-impliesthatmaintenance\'Iillnotbeviouslyinaccessibleareatointrusion;'bneaccessible.However,thereisahighim-mdsoils:impactislowonperma-neededandthatinplacesrevegetationandhunting;sincecaribouandmoosearepactonwilderness,especiallyifanaccessmaybenecessary.~lediumtohighrateofpresent,thiscouldhaveasignificantroadisbuilt.iumonerosion.firespread;highresistancetocontrol;impactonhuntingpreserve.Firingon10\'1resistanceinalpinetundra,tundraareascouldseverelyimpactcari-bouhabitat.actislow·level.ShallowpermafrostClearingvariesfromspruce-hardwoodstoSomeenhancementofbearandmoosehabitatainedareassusceptibletodegrada-highbrush.~bstvegetative1055fromac-inheavierforestedareas,butlittlesigni-ApartfromsettlementsalongDenaliHighway,~diumimpactonscenicquality;areaisofcessroads.Slwregrolvthimpliesthathighscenicquality,butlinecanbecon-heaccessroadcanavoidthesemaintenance\'Iillnotbeneeded.Mediumtoficantchange.Nonewareasopenedup.nodevelopments-noimpacts.mpactwillbelow,highrateoffirespread;highresistanceOverallimpactislow.cealed.Fntiresegment\'IithinMMPCPMZone.tocontrol.npotentialthroughoutstretch,HeavyclearinginvalleybottombyYanertSomehabitatdestructionandenhancementdueTheadditionofathirdright-of-waythroughdrockincanyonswillprovidesolidFork;lighterclearingthroughoutrestoftoclearing;overallimpactofclearingisthecanyonsmaycausecongestionunlesssevereimpactonscenicquality;notonlyislationsbutwillinhibitaccessroadroute.Highrateoffirespread,highre-10\'1.None\'lareasopeneduptohunting.rights-of-wayareconsolidated,Possiblecon-thecanyonanareaofhighscenicquality,nifneededoncanyonslopes.?istancetocontrolonvalleyfloor;10\'1Constructionactivitiescombinedwithtrans-nectiontoGVEAlineatHealy,Potentialtaptoconcealmentofthelineishardandthe\'lestnedareashavehighpermafrostresistanceinalpinetundra.portationuseofcorridormaytemporarilyprovideconnectionofCantwellintosystem.bankoftheNenanaisparkland.1susceptibility,Lowsiltationimpact.repulsesomemannnalssuchaswolfandbear.1potentialandexposedbedrockonBeavyclearingonvalleybottomstonoConstructionactivitiesmayinhibitcaribouHighimpacttowildernessquality,butlimitedleareasofpoorlydrainedsoilsus-clearinginalpinetundra.510\'1regrowthandsheepactivities.Overallhabitatmodi-totheimmediatevalleyoccupiedbyline;ermafrostdegradationinwiderval-inhigherelevations.Highrateoffirefication10\'1,especiallyifwinterroadsnatureofterrainwilladequatelyconceallineRivertoodeepforfordingandisspread;highresistancetocontrolatand/orhelicopterconstructionisused.Noneunlessitisrunonridges(unlikelyinthis10\'lerelevations;lowresistancetocon-Firecanseriouslyimpactsleepandcaribouormally.sosiltationwillhavelowtrolinalpinetundra.habitat.Largene\'lareaopenedbyaccesssegment),road\'Iillincreasehuntingpressure.npotentialonslopes;highsuscepti-HeavyclearinginYanertFork;ConstructionactivitiesmayinhibitcaribouHighimpacttowildernessqualityexceptfor'mafrostdegradationonpoorlylittletonoclearingelse\'lhere.Slowregroh~hinhigherandsheepactivities.Overallhabitatmodi-PossiblelineconnectionatHealyPowerlowerMoodyCreek(VsibelliMineworks),leyfloors,TowardsHealy,wellficationlow,especiallyif\'linterroads/5aresubjecttomediumerosionelevationsandpoorlydrainedareas.Highhelicopterconstructionisused.FirecanPlant-Usibelli~lineroadsmaybeusedNatureofterrainwillconceallineexceptfortolowrateoffirespread;highto10\'1foraccess.ridgealonglowerMoodyCreekwherelinewilldlowsusceptibilitytopermafrostresistancetocontrol.seriouslyimpactsheepandcaribouhabitat.CrossingneededonHealyCreek:Largenewareaopenedbyaccessroad\'Iillbesilhouetted,limpact.increasehuntingpressure.lplainhasmediumerosionpotential.Clearingwillenhanceconsiderableamount0Privateholdings(claims,homesteads,etc.)NoimpactonDryCreekarcheologicalsiteedareassubjecttopotentialperma-Heavyclearingformostofrouteexceptalongroute-townsofHealy,Lignite,sinceline\'IilltraveloneastbankofNe-Goldstreammoosehabitat.CaribouconfinedtowestNenana:ThesetownsmaybeaffectedbynanaRiver.~diumimpactnearHealyandationandfrostheaving.nearHealy.IntroductionofbrushintobankofNenanaandthus\'Iillnotbeaffectedhlyerosiveandsusceptibletoright-of-\'Iay.Highrateoffirespread;iflineTunSoneastbank.Nonewsignifi-'constructionactivitiessincetheyareintheGoldstreamHills;10\'1impactalonglegradationandslopeinstability,highresistancetocontrol.cantareasopenedup,particularlyifGVEAtransportationcentersalongthesegment.lowerNenanaRiver.ImpactwillbelessIfGVEAlineisadjoined,therewillbeaifGVEAright-of-wayisadjoined.Lowim-TananaRiverneeded:lowsiltationright-of-wayisparalleledoradjoined.conflictwiththeFAAairportatNenanaforpacton\'Iilderness.clearance.liver:10\'1erosionandpermafrostHeavyclearingonTanana10\'llands.LighttoConstructionactivitiesandfireinUpperLowimpactonscenicqualityduetoextreme)werWoodRiver:mediumtohighnoclearinginl/pperWoodRiverinalpineWoodRiverwillnegativelyaffectcaribouand,inaccessibility.Wildernessqualitywillrrpactsonpermafrost.Highsus-andmoisttundra,andtheTananafloodplainsheep.ClearinginLowerWoodRiver\'Iillen-Ne>n€receivehighimpactinupperWoodRiver,toheaving.Lo\'ltomediumero-nn.l5kegs.Varyingratesoffirespreadandhancemoosehabitat.Verylargeareaopenedmediumto10lvalonglowerWoodRiverbe-ial.CrossingofTananaRivercontrollability.upbyaccessroad\'Iillbesubjectedtocauseofvaryingconcealmentandpresencegreaterhuntingpressure.ofcivilization.NENANAIMPACTS SOILSVEGETATIONSuccessivelylessclearingassegmentgErosionimpactislow.Shallowpermafrostinnorth.InBroadPass,notreesneedclearingandtheonlyvegetationlostGoldCreek-Cantwellpoorlydrainedareassusceptibletodegrada-wouldbefromaccessroad.SlowregrOl;(10)tion;sincetheaccessroadcanavoidtheseimpliesthatmaintenancewillnotbeneareas.thisimpactwillbelow.andalsothatrevegetationmaybenecesalongsomeareas.Mediumtohighratefirespread;highresistancetocontrolClearingvariesfromdensespruce-hardw,toalpinetundra.~bstvegetationlossPoorlydrainedloam:impactonpermafrostinwillbefromaccessroad.SlowregrowtJWatana-WellsCreekvi~thiscaseishigh,andfrostheavingisposs-impliesthatmaintenancewillnotbeBrushkanaCreek(11)ible.Uplandsoils:impactislowonperma-neededandthatinplacesrevegetationfrost,mediumonerosion.maybenecessary.Mediumtohighrate(firespread;highresistancetocontrollowresistanceinalpinetundra.Erosionimpactislow·level.ShallowpermafrostClearingvariesfromspruce-hardwoods1highbrush.~bstvegetativelossfromWellsCreekCantwellinpoorlydrainedareassusceptibletodegrada-cessroads.SlOl,regrolvthimpliestha1(12)tien;sincetheaccessroadcanavoidthesemaintenancewillnotbeneeded.Mediurareas,thisimpactwillbelow.highrateoffirespread;highresistartocontrol.Higherosionpotentialthroughoutstretch.HeavyclearinginvalleybottombyYanEExposedbedrockincanyonswillprovidesolidFork;lighterclearingthroughoutrestCantwell-Healy(13)towerfoundationsbutwillinhibitaccessroadroute.Highrateoffirespread,highconstructionifneededoncanyonslopes.~istancetocontrolonvalleyfloor;l(Poorlydrainedareashavehighpermafrostresistanceinalpinetundra.degradationsusceptibility.Lowsiltationimpact.HigherosionpotentialandexposedbedrockonfJeavyclearingonvalleybottomstonoslopes.Someareasofpoorlydrainedsoilsus-clearinginalpinetundra.SlowregrmWellsCreek-Deanceptibletopermafrostdegradationinwiderval-inhigherelevations.HighrateoffilCreek(14)leyfloors.Rivertoodeepforfordingandisspread;highresistancetocontrolatlowerelevations;lowresistancetocorsilt-ladennormally,sosiltationwillhavelowtrolinalpinetundra.impact.Higherosionpotentialonslopes;highsuscepti-HeavyclearinginYanertFork;bilitytopermafrostdegradationonpoorlylittletodrainedvalleyfloors.TowardsHealy,wellclearingelsewhere.SlowregrowthinhiDeanCreek-Healy(15)drainedsoilsaresubjecttomediumerosionelevationsandpoorlydrainedareas.Hito10\,rateoffirespread;hightolowpotentialandlowsusceptibilitytopermafrostresistancetocontrol.degradation.CrossingneededonHealyCreek:lowsiltationimpact.Nenanafloodplainhasmediumerosionpotential.Poorlydrainedareassubjecttopotentialperma-Heavyclearingformostofrouteexcelfrostdegradationandfrostheaving.GoldstreamnearHealy.IntroductionofbrushintHealytoEster(16)hillsarehighlyerosiveandsusceptibletoright-of-way.Highrateoffirespreepermafrostdegradationandslopeinstability.highresistancetocontrol.CrossingofTananaRiverneeded:lowsiltationimpact.UpperWoodRiver:lowerosionandpermafrostHeavyclearingonTananalowlands.Lig:impacts.LowerWoodRiver:mediumtohighnoclearinginlJpperWoodRiverinalpiDeanCreektoEsterpotentialimpactsonpermafrost.Highsus-andmoisttundra,andtheTananaflood.(WoodRiver)(17)ceptibilitytoheaving.Lowtomediumero-muskegs.Varyingratesoffirespreadsionpotential.CrossingofTananaRivercontrollability.needed. VEGETATIONLngthroughoutsegment;noneed:e.PossibledisruptionofldsubsequenterosiononslopesdegradationonpoorlydrainedhavelowtomeditnnresistancefromPaxsontoDonnellyDomelearingasroutegoesnorth.tioninclearingsinSpruce-ts.Slashmustbedisposedoftleinfestations.Vegetationhighrateoffirespreadandresistancetocontrol.ImpactsbelessifAlyeskaright-of-wayDined..overmostofroute;someclear..;ruce-Hardwoodsnecessaryaround'elchinaRiver.Riskofbeetle'slash.VegetationonUpper..uhaslowtomeditnnrateoffuelitnntohighresistancetocon-:iononlowerLittleNelchinahaspreadandhighresistancetoryclearingthroughoutsegment.:tionwilloccurinclearings.~infestationofslash.Vege->hrateoffirespreadandhigh>control.OverallimpactswouldAlyeskaright-of-wayweretobepossible.metaPassandGunsightMountainrequiredmediumtoheavyclear-~length.Brushintroductionclearings.Clearingswillneed:enance.Riskofbeetleinfest-t.Vegetationhasmeditnnto:irespreadandhighresistanceDELTAANDMATANUSKACORRIDORS-----IMPACTSWILDLIFEConstructionactivitiesmayinterferewithcariboumovements.Lowimpactonmooseactivities.Littlechangeinhab~tatfromconstruction,unlessseverescarr1ngorex-cessivefiresaffectvegetation.AccessroadwillopenuptheButteCreekareaandhuntingpressuresmayincrease.Possibleinterferencewithcaribouandbison'movements.Lowimpactonmooseinsouthernpartbutwillenhancehabitatonmoreheavilyforestedareas.LowimpactonDallSheepinDeltaCanyonsincelineWill.staylow.Minimaldestructionofduckhab1tatifright-of-waycrossesSalchasloughsandpondsbvDonnellyDome.SiltationinGul-kana,SalchaandShawcreekswillaffectanadromousfish•PossibleinterferencewithNelchinacaribouherdmovements.LowimpactonmooseexceptonlowerLittleNelchina,whereclearingswillenhancecaribouhabitat.Thisrouteopensaverylargeareatohunting.PossibleinterferencewithNelchinacaribouherdmovements.Althoughmoosearentnnerous,majorimpactshouldbetheenhancementofhabitatalongclearings.Firewillbedestructivetocaribouhabitat,mayenhancemoosehabitat.OverallimpactswouldbelessiftheAlyeskaright-of-wayweretobeadjoined.LowimpactonDallSheep..Clearingwi~ler.t-hancemoosehabitat.Lowlmpactsonw1ldhfeingeneral.EXISTINGDEVELOPMENTSNoexistingdevelopmentsexceptforscarcesettlementsalongDenaliHighway.Noimpact.SettlementsalongRichardsonHighwaymaybeimpactedbylineright-of-way.acquisiti?n.To,vnsofDeltaJunctionandB1gDeltaw1IIreceivesomeimpacts,mostlybeneficial,.fromtransitofmaterialandlabor.POSS1-blecongestionofright-of-waythrough.DeltaCanyonunlessrights-of-wayar~consol1dated.Overallimpactswouldbeless1fAlyeskaright-of-wayweretobeadjoined.N::meTownofGlennallenwillreceivesomeimpacts,mostlybeneficial,fromtransitofmaterialandlabor.Noothermajorimpacts.OverallimpactswouldbelessifAlyeskaright-of-wayweretobeadjoined.ConsiderablefarmingcorrummityonPalmer-conflictsmayariseinlanduse.Roadsbyabandonedcoalmineareascanbeusedasaccess.LowerMatanuskaValleyhasahighratioofprivatelyownedlandwhichwillresultinacquisitionforright-of-way.SCENICQUALITY/RECREATIONonviewasseenfromDenallH1ghway,lmecanbeconcealedsomewhatfromhighway.Prelim-inaryroutesurveysinTangleLakesAr<::heo-logicalDistrictwilllocatearcheolog~calsites;adjustmentofrout~would.allev1ateconflict.Right-of-wayw1llavo1drecrea-tionareasandeastendofDenaliHighwaytolessenimpactonrecreationandscenicquality.HighimpactsonscenicqualityfromPaxsontoDonnellyDome,meditnntoDeltaJunction,andlowtoEielsonA.F.B.Impactisafunc-tionofexistingscenicqualityandabilitytoconcealthetransmissionline.Iftrans-missionlineisroutedparalleltoRichardsonHighway,recreationareasandhist?ricsiteswillbenegativelyaffected.If.lm~ad-..joinstheAlyeskaright-of-way,lmpactsWlIIbeless.Wildernessqualitysufferssincethiswouldbeapioneercorridor.Lowimpactonscenicquality-linecanbeeasilyconcealedforentiresegment.Pos-sibleconflictswithrecreationalandhis-toricsitesdependingonfinallocation.ImpactswouldbelessifAlyeskaright-of-wayweretobeadjoined.SevereimpactonscenicqualityofUpperMatanuskaValleyandTahnetaPass.Partialconcealmentispossible.Impactlessensasvalleywidens,andagriculturalusebecomesmoreapparentan~concealment~creases..LowimpactonKInkArmarea;lmecanaVOldallrecreationareasandbeconcealedfromroads.DELTA/MATANUSKAIMPACTS WatanatoPaxsonviaButteCreek(18)PaxsontoFairbanks(19)WatanatoSlideMtn.viaVee(20)PaxsontoSlideMtn.viaGlennallen(21)SlideMts.toPointMacKenzie(22)SOILSVulnerabletopermafrostdegradation,Low-lyingareasaresusceptibletoheavingandsettlement,Erosionpotentialismediumtohigh,Accessroadwillneedtobeadequatelyculvertedoverareasofpoordrainage,InDeltaCanyonbedrockiseasilyreachedfortowerfoundations,ThixotropicsiltsnorthofSummitLakecombinedwithseismicriskwillaffectreliabilityofline,PhelanCreek,TananaRiver,GulkanaRiver,ShawandSalchaCreeksneedcrossings,Lowareasvulnerabletoheaving,Considerableimpacttopermafrostpossiblefromaccessroad;winterconstructionpreferable,Accessroadwillneedtobeadequatelyculvertedoverareasofpoordrainage.Vulnerabletoheaving,Considerableimpacttopermafrostpossiblefromaccessroad;winterconstructionpreferable,Accessroadwillneedtobeadequatelyculvertedinareasofpoordrainage,OverallimpactswouldbereducedifAlyeskaright-of-wayweretobeadjoinedwherepossible,Erosionimpactfromconstructionandaccessroadcanbehigh.Permafrostdegradationisunlikely.ImpactofconstructionandroadonKnikArmsoilswillbelow,Frostheavingisveryprobableinpoorlydrainedareas,VEGETATIONMinimalclearingthroughout.segment;no.needformaintemince.Possibledis1Uptionofsurfacematandsubsequenterosiononslopesorpermafrostdegradationon~oorly~rainedareas.Fireshavelowtomedlumreslstancetocontrol.LightclearingfromPaxsontoDonnellyDomearea.Heavyclearingasroutegoesnorth.BrushintroductioninclearingsinSpruce-Hardwoodforests.Slashmustbedisposedoftopreventbeetleinfestations.Vegetationhasmediumtohighrateoffirespreadandhightomediumresistancetocontrol.ImpactsoverallwouldbelessifAlyeskaright-of-wayweretobeadjoined.Lightclearingovermostofroute;someclear"ingthroughSpruce-Har~oodsne<;:essaryaroundlowerLittleNelchinaRiver.RlSkofbeetleinfestationofslash.Vegetat~ononUpper,Susitnaplateauhas10':'tome~lumrateofflYespreadandmediumtohlghre~lstanceto,con-trol.VegetationonlowerLlttl~Nelchmahashighrateofspreadandhighreslstancetocontrol.Mediumtoheavyclearingthroughoutsegment.Brushintroductionwilloccurinclearings.Riskofbeetleinfestationofslash.Vege-tationhashighrateoffirespreadandhighresistancetocontrol.OverallimpactswouldbereducedifAlyeskaright-of-wayweretobeadjoinedwerepossible.ExceptforTahnetaPassandGunsightMountainarea,segmentrequiredmedium~oheavy<;:lear-ingforentirelength.BrushlJ:trodu<;:tlOnwilloccurinclearings.Clearmgswlllneedperiodicmaintenance.~skofbeet~einfest-ationofslash.VegetatlOnhasmedlUmtohighrateoffirespreadandhighresistancetocontrol.DELTAANDMATANUSK,IMPACTSWILDLIFConstructionactivitiesillcariboumovements.Lowiactivities.Littlechangconstruction,unlesssevecessivefiresaffectvegeroadwillopenuptheButhuntingpressuresmayincPossibleinterferencewit}movements.Lowimpactonpart,butwillenhancehalheavilyforestedareas..uSheepinDeltaCanyonsm(low.Minimaldestructionifright-of-waycrossesS,pondsbyDonnellyDome.~kana,SalchaandShawcreEanadromousfish.Possibleinterferencewitherdmovements.LowimpaonlowerLittleNelchina,willenhancecaribouhabiopensaverylargeareatPossibleinterferencewitlherdmovements.AlthoughmajorimpactshouldbethEhabitatalongclearings.destructivetocaribouhalmoosehabitat.OverallinlessiftheAlyeskaright-beadjoined.LowimpactonDallSheep..hancemoosehabitat.Low:ingeneral. ENVIRONMENTALIMPACTSOFCORRIDORSImpactsofPreferredCorridorSusitna-lSoils:InthelowerSusitnaValleythecorridorwillencountersubstantialareasofpoorlydrainedsoilsthatalthoughnotvulnerabletoerosionwill,however,posetheproblemoffrost-jackingoftowerfootingsandanchors.Unlessmeasuresaretakentocounteractthispotentialproblem,additionalmaintenanceanditscorrespondingimpactswillbenecessary.Thebetterdraineduplandsoilsarelessvulnerabletoheaving,but,aswithmanyfloodplainsoils,israthersusceptibletoerosion,pa.rticularlystreamerosion.Sincetherelativeproportionsofthesetwosoiltypesvaryfrompoorlydrainedsoilsinthesouthernportiontowelldraineduplandsoilsinthenorthern,theimpactsassociatedwiththemwillhaveasitrilardistribution.Accessroadconstruction,althoughrequiringheavyclearing,willberelativelyeasyintheuplandsoils.Watererosionwilloccursomewhat,particula.rlyduringtheconstructionphase,influencingwaterqualityinthe<clea.rwaterstreamscrossed.Roadconstructionintheareasofpoorlydrainedpeatswillinvolveproblemsofhardeningthesurfacesufficientlytobearconstructiontraffic.Ruttingandgougingoftrackswilloccurifconventionalvehiclesattempttocrossanunhardenedsurface.Corduroy,piles,deepfills,anddrainagearemethodsofhardeningmuskegsurfaces,allofwhichareexpensiveandwillinvolvelocalimpacts.Avoidanceoftheproblembycarefulrouting,wintercon-struction,and/oruseoflow-pressuretreadvehicleswillinvolvelessimpacts.Permafrostisgenerallynotpresent.Whereisolatedmassesdoexist,theyareburiedfairlydeeply.Potentialthermaldisruptionofperma-frostalongthiscorridorisunlikely.ThecorridorparallelstheSusitn.a,involvingnocrossing,butinter-sectsseveraltributariesfromtheTalkeetnaMountains.Fordingofmachineryandyardingoflogsacrossthesestreamswillresultinincreasedsedimentation.Inthesmallerclearwaterstreamsthismayresultinreductionofspawninghabitatandpotentialgilldamageinfishdown-streamofthecrossing.Vegetation:IfthelinetoPointMacKenzieis345kv,theamountofclearingfortheright-of-waywillbeupto2,308acres;ifthelineistobe230kv,theamountofclearingwillbeupto2,060acres.TheactualAppendixII35 AppendixI1-36clearingwillprobablynotbeashighastheseacreagessincevegetationalongsomestretchesUlaynotrequireclearing,exceptaroundtowerbases.Theterrainbeingrelativelyflat,theaccessroadcanutilizetheright-of-waywithoutadditionalclearing.Theimmediateeffectofthisclearingwillbethedestructionofthevege-tation;themuchmoresignificantimpactwillbeuponerosionand'\vildlifehabitats.Inhillyterrainmechanicalclearingmethodssuchasbulldozingwillcauseconsiderabledisruptionofthesoilandsubsequenterosionandstreamsedimentation..Theuseofbrushbladesorrotarycutterswillreducethiseffect.Onsteepslopeshandclearingwillmitigatetheotherwiseheavyerosionpotentiallikelywithmechanicalclearing.Toreduceavailablefuelforforestfires,andtoreducepotentialinfesta-tionofhealthytreesbysprucebeetles(Dendroctomusrufipennis)andipsbeetles,slashmustbedisposedof.Thiscanbeeitherby.saleofmarket-abletimberorbyburning.Althoughburningwillreduceairqualitytempor-arily,itismoreeconomicalandlessdamagingthanthealternatives.(SeeMitigatingMeasures)Regrowthratesalongthiscorridorarefastenough,particularlyinthesouthernportion,towarrantperiodicsuppressionoftallgrowingtreeswhichposeahazardtothetransmissionline.Thepreferredmethodalongthiscorridorismanualapplicationofasuitableherbicide.Theamountofclearingtobemaintained,themodestregrowthrates,andhighcostoflabormakethisalternativepreferrableinthiscorridoroveraerialapplicationofherbicidesontheonehand,orhandcuttingofresidualtreesontheother.Ifproperapplicationtechniquesareadheredto(seeMitigatingMeasures),therewillbenootherimpactsotherthanthemaintenanceofasub-climaxvegetation.Accidentaloversprayingorwinddrift,orimproperdilutionresultinginunnecessarydestructionofvegetation,andsprayingofwaterbodiesresultinginhabitatdestructionforaquaticlifearenotlikelytooccurwithmanualapplication.Sectionsneedingvegeta-tionsuppressionoccursinthebottomlandspruce-poplar,lowlandspruce-hardwood,anduplandspruce-hardwoodforests,particularlyinthebottomlandspruce-poplarandmuskeg-bogareas,whichcompriseasignificantproportionoftheecosystemscrossedbythiscorridor,willneedlittleclearingandnovegetationsuppression.Lowlandspruce-hardwoodareaswillnotneedtobemaintainedasoftenasbottomlandspruce-poplar.Wildlife:Alterationofvegetationpatternswillaffectwildlife.Thiscorridortraversesmanyareasofmooseconcentration,a.ndmooseshouldbenefitfromtheintroductionofbrushresultingfromtheregrowthontheclearing.Sincetheclearingmustbemaintained,thisbrushareawilllastforthelifeoftheline.~,fostbrushareasareintransition, changingfromthebrushphasetosomeotherphasenearertheclimacticphase;thebrushinatransmissionclearingcanbecountedasamorepermanentsourceofbrowse.Animalsdependentuponclimacticforest,suchassquirrels,willsufferlossanddisplacement.However,theirfasterreproductiverateswillallowtheirpopulationstoadjustrapidly.Mostanimalswillbenefitfromtheedgeenvironment,offeringbothforageandcoverfortheadjacentforestandbrush.Initially,animalmovementsmayoccuralongtheright-of-way,butasthebrushgrowsintoadensecoverthiswillbelimited.Inanyevent,thisimpactshouldbelowinthiscorridor.Constructionitselfwillaffectwildlife.La.rgermammalsmaytemporarilyleavetheareatoreturnaftertheconstructionactivity.Smalleranimalswillsufferlossofindividuals,butshouldrecuperaterapidlyoncecon-structioniscompleted.Thedensityofforestinthiscorridorwillallowanimalstomoveonlyashortdistancetoavoidcontactwithconstructionactivities.Vegetationsuppression,bywhatevermethod,willperiodicallyremovecoverfromalongtheright-of-way.However,duetothesurroundingcoveroftheunclearedforests,thisimpactwillbeinsignificant.Recreation:TheSusitna-1corridorwillapproachwithin10milesofseveralrecreationalandwaysideareasinthelowerSusitnavalley.ThelargestoftheseistheNancyLakesRecreationArea.Inaddition,thecorridorwillrunadjacenttotheDenaliStateParkfor22miles.However,theSusitnaRiverwillseparatethecorridorfromthePark;themainaccesstolandswithintheParkistheAnchorage-FairbanksHighway,andthisisanaverageof10milesawaytothewestovera2,000to2,500feethighridge.Dependinguponthepoliciesofthelandmanagingagenciesinvolved,thiscorridorwillprovideaccesstoareaspreviouslydifficultofaccess.ThelargestsuchareaisthatsouthofNancyLaketoPointMacKenzie.Denseforestandmuskeglimittravel.AnothersuchstretchisthatfromTalkeetnanorth.AlthoughtheserviceroadparallelstheRailroad,itwillofferasignificantlyeasieraccessbycarortrucktothiscorridor.Manycabinsalongthesestretcheswillbeprovidedwithbetteraccess;however,thecreationofeasieraccessmayinterferewithisolationdesiredbymanyoftheowners.IfnobridgeisprovidedovertheTalkeetnaRiver,theserviceroadwillbelessattractivetocasualtravellers.AppendixI1-37 AppendixI1-38CulturalResources:TheNationalRegisterofHistoricandArcheologicalSiteslistsonlyonesiteinthearea,KnikVillage.Thecorridorwillrunatleast10milestothewestofthissite.Itislikelythatarcheo-logicalsiteswillbefoundalongthecorridor,eitherduringthelocationsurveyorduringconstruction.Ifso,minorrouterelocations,orcarefultowerlocations,willprotectthesesites.Inadvertentalterationofasitewillreduceordestroyitshistoricalvalue.ScenicResources:Thiscorridordoesnottraverseanyareasofgoodorhighqualityscenicvalues.Thenorthernportionis,however,morescenicthanthesouthernportion.Inthenorthernportionthefairlycontinuousmoderatelydenseforestwillprovideamplescreeningfromtransportationroutes.Furthersouth,theforestsaremoreintermingledwithopenmuskeg.Glimpsesofthetransmissionlinecanthenbeseenfromthehighwayorrailroadthroughthesemuskegs.SouthofNancyLakethecorridorandthetransportationcorridorsdiverge,andalthoughcOVerbecomesmoresporadic,thelinewillnolongerbevisiblefromthetransportationroutes.ThetransmissionlinewillnotbevisiblefromtheNancyLakeRecreationArea.AstheAlaskaRailroadandthetransmissioncorridorapproachGoldCreek,thevalleybecomesmoreconfined,andscreeningbecomesmoredifficult.However,itappearsthatthelinecanbeconcealedthroughmostofthisportion.LandUseandResources:FromPointMacKenzietoNancyLakethecorridorfollowsnoexistingcorridorfor32miles.NorthofNancyLaketoGoldCreekthecorridorparallelstheAlaskaRailroad,andtoTalkeetnatheAnchorage-FairbanksHighwayandMatanuskaElectricAssociationdistributionlines.Noimpactisexpectedontheseutilities.Althoughagricultureinthisareaisgenerallylimitedtoafewfarmsandsubsistencegardens,thereispotentialinthebetterdrainedsoilstosupportfarming.ThecorridorwillencountersomeagriculturenearNancyLake,andagainabout25milesnorthnearthesettlementofMontana.Impactonagriculturewillbeverylow.GoodstandsofblackcottonwoodandbalsampoplarexistneartheTalkeetnaRiver,butthereisnoextensiveforestrytobeimpactedbythecorridor.Futureforestrymayutilizetheaccessroadbothforloggingandasafireroad,butthisimpactislowanddependsalsouponthelandownership. Impactonmineralresourcesislow;thecorridordoesnottraversesignificantareasofpotentialmetallicminerals,anddoesnotapproachanyexistingcoaloroildevelopmentsalthoughthepotentialforcoal,oilandgasexistsalongnearlytheentirelengthofthecorridor.Duetothehighcostofalow-loadtapona345kvline,thelikelihoodofthedevelopmentoftheseresourcesduetotheproximityofatransmissionlineislow.Social:Fewtownsareencounteredbythecorridor.Wheneverpossible,thefinallocationwillcircumventcommunities.Theconstructionphasecanlastsomewherefromthreetofiveyears.Duringthattime,workonthetransmissionlinewillaffectthesecommunities.Thenumbersofworkersneededonatransmissionlinerelativetoapipelineislow.Workerswillbehousedincamps,orwillbebasedinAnchorageorFair-banks,bothofwhicharelargeenoughtoabsorbtheworkforce.Laborwillprobablyberecruitedfromthesecitiesorbroughtinbythecontractors.Littleornolaborforcewillbedrawnfromthesmallercommunitiessinceitisnotexpectedthattheirresidentsmighthavetheskillsandqualificationsfortransmissionlinework.Someeconomicimpactcanbeexpected,asflyingservices,motels,restaurants,andentertainmentsreceivebusiness,notonlyfromthetransmissionlineworkers,butfromrelatedpersonnel,also.Talkeetnaistheonlycommunity,exceptAnchorage,receivingtheseimpactsfromcorridorSusitna-l.ItcanbeexpectedthatAnchoragecouldacceptthisimpactwithlittlestrain,buttheimpactmaybehighforTalkeetna.Theimpactsmaybeadverseinthatservicesmightbetemporarilymonopolizedbytheconstructionactivity,andgoodinthatitwouldbringconsiderablemoneytobusinessinthetown.ImpactsofPreferredCorridorNenana-l_Soils:TheincidenceofpermafrostincreasesfromDevilCanyonnorthtoFairbanks;however,itisgenerallydiscontinuous,withafairlydeeptable.Impactsresultingfromthermaldegradationwillbelow,exceptforsoilsintheMoodyareawhichareice-rich.AsinSusitna-l,soilsvaryfrompoorlydrainedsoilsonlowlands,andbetterdrainedsoilsonslopes.Erosionpotentialforthemajorityofthecorridorislowtomediumsincethegreaterportionofthecorridorisonrelativelylevelland.TwosignificantexceptionsarethesectionsintheNenanaCanyonandtheItGoldstreamHills.ItTheNenanaCanyonareawouldposesevereerosionalproblemsforanaccessroadduetothesteepslopesencountered.Discontinuouspermafrostisfound,whichpresentsahighpotentialfordegradation.AppendixI1-39 AppendixI1-40Duetothephysicalandpoliticalrestraints,thecorridorwillhavetotraversemanyslopes.Soilsareoftenshallowontheseslopes;indeed,manyofthemaretalus.TheuppercanyonisconstrictedbetweenPanoramaMountainandtheNenanaRiver,andanextensive,unstabletalusslopeliesatthefootofPanoramaMountain.Inthelowercanyon,thin,unstablesoilblanketsthesteepslopetotheeastofthehighway.Wherethecorridortraversesslopessuchasthese,erosionwillbeaseriousproblem,especiallyonthinsoilsorunstablesoils.ThisimpactwillbeespeciallyobjectionablesinceerosionscarsmaybevisiblefromtheAnchorage-FairbanksHighwayandMt.McKinleyNationalPark.Becauseofthepotentiallysevereimpactofouraccessroadinthisarea,nonewillbebuiltandhelicopterconstructionwillbeused.TheNenanaCanyonareaisalsointhevicinityofseverallargefaults.TheDenaliFaultcrossesthecorridorjustnorthofCantwell,andanotheractivefaultisencounterednearHealy,northofthelowercanyon.Thisfactorwillaffectlocationofthetransmissionlineonunstableslopes.ThesoilintheGoldstreamHillscontainslensesoffinegrainmaterialwhich,combinedwiththeslopesencounteredbythecorridor,posesapotentialerosionproblem.Fortunately,rainfallisscantinthisarea.ThelowlyingareasintheGoldstreamHillshaveashallowpermafrosttable;soavoidingthepotentiallyerodablefinegrainsoilsbylocatingthetransmissionlinelowwillpresentaproblemwithfrozensoilsandmuskegs.ThecorridorwillcrossPortageCreek,theWestandMiddleForksoftheChulitnaRiver,theJackRiver,theNenanaRiver,YanertFork,HealyandLigniteCreeks,andtheTananaRiver.WiththeexceptionoftheNenanaandTananaRiversandYanertFork,theseareclearwaterstreams.Fordingsandcrossingswhichdisturbthebottomwillaffectwaterquality,aswillrun-offintothesestreamsfromadisturbedclearing.Vegetation:Upto1,440acreswillneedclearingalongthiscorridor.Actualacreageofclearingwillprobablybemuchlesssincethisfigureassumesclearingtothefullwidthoftheright-of-way.Inmanyareas,onlytheareasaroundthetowerbaseswillrequireclearing,particu-lal'lyinthelowlandspruce-hardwoodandmuskeg-bogecosystems.Theheaviestclearingswillbenecessaryinthebottomlandspruce-poplaranduplandspruce-hardwoodecosystemsalongthelowerNenanaRiverandtheTananafloodplain.Alongthegreaterpartofthecorridor,theaccessroadcanbeincorporatedintotheclearingduetolevelterrain.FromDevilCanyontoHealy,therewillbenoaccessroad. Themostimmediateeffectofclearingwillbethedestructionoftheclearedvegetation.Thetimberclearedfromthebottomlandspruce-poplarwillbesold,ifmerchantable.Non-merchantabletimberwillbeburnedifanaccessroadispresent.Withnoaccessroad,machinerycannotbebroughtinforstacking,burning,orchipping,anddownedtimberwillbeleftalongtheclearing.Beetleinfestationwillbeofconcernmainlyinthebottomlandspruce-poplarecosystem.Somedisruptionofthesoilfromclearingistobeexpected;increasederosionbecauseofthis,andenhancedbythelackofcover,willresult.Ifvegetationiscleareduptoriverbanksonstreamcrossings,thismayresultinadditionalsedimentation.Clearingwillentailhabitatmodification,tobediscussedunderIIWildlife.IIRegrowthratesalongthiscorridorareslowenoughtonotrequireaprogramofvegationsuppressionotherthanoccasionalcuttingduringroutineinspectionandmaintenancepatrols.Wildlife:Therewillbelossofindividualsmalleranimals,anddisplace-nlentofothers;however,thisisatemporarysetback.Highreproductiveratesofsmallermammalsandre-invasionwillalleviatethisimpact.Apermanenthabitatmodificationwillresultfromtheclearingandmaintenance;acorridorofbrushwillbemaintainedthroughotherwiseforestedland.Animalsdependentuponclimaxforest,suchassquirrels,willsuffersomehabitatloss.Animalsdependentuponbrushandforbsforbrowsewillgain.Apartfromlocalconcentrations,theonlymajormooseconcentrationalongthiscorridoroccursfromHealytotheTananaRiveralongtheNenanaRiver.Aftertheconstructionphase,moosewillbenefitfromthelIedgellenviron-ment,offeringincreasedbrowseimmediatelyadjacenttoforest,whichprov-idescover.Dependinguponthefinallocation,theaccessroadmayresultinadditionalhuntingpressureuponmooseinthisarea.Thiswillalsodependuponthechanceofmorehuntersintheareathanpresentlysinceifthenumberofhuntersremainsthesame,thereisnoreasontosuspectthatincreasedaccesswillresultinbetterhuntingsuccess.InpassingthroughthelowerNenanaCanyon,theNenana-lcorridortraversesDallsheephabitat.However,sincethesheeptendtoinhabitareashigherthananyfeasiblelinelocation,andsincenoaccessroadwillbeusedinthisarea,impactonDallsheepwillbelowtonone.AppendixI1-41 AppendixI1-42Recreation:TheNenana-1corridorwillparalleleightmilesofthenortheastborderofDenaliStatePark,butwillbeseparatedfromtheboundarybyIndianRiver,theAlaskaRailroad,andatleastonemileofbuffer.Furthernorth,itparallelstheeastborderofMt.McKinleyNationalParkfor30miles,beingseparatedbytheNenanaRiver,theAnchorage-FairbanksHighway,andtheAlaskaRailroad.AtnopointwillthecorridorcrosslandsproposedasadditionstotheMt.McKinleyNationalPark.Theaccessroadwillopenupnoextensivepreviouslyinaccessibleareassinceitwillparallelexistingtransportationafewmilesdistant;norecognizedwildernessareasareinfringed.Useoftheaccessroadbythepublicwillbedeterminedbytherelevantland-managingagency.IfthefinalroutelocationcrossestheClearMEWS,restrictionsmaybeplaceduponpublicuseofthisportionoftheaccessroad.CulturalResources:TheNationalRegisterofHistoricandArcheologicalSiteslistsonlyonesiteapproachedbytheNenana-1corridor,theDryCreekarcheologicalsite.ThisliestothewestofHealy,theNenanaRiver,andtheexistingtransportationcorridors.SincethecorridorrunsalongtheeastbankoftheNenana,therewillbenoimpactonthissite.IfthefinalroutesurveydisclosesanunsuspectedarcheologicalorhistoricalsitewithpotentialforinclusionintheNationalRegister,minorrouterelocations,orcarefultowerlocation,willprotectthesesites.Inadvertantalterationofasitewillreduceordestroyitshistoricalvalue.ScenicResources:ThecorridorpassesthroughanarearecognizedasbeingofgoodtohighscenicqualityfromDevilCanyontoHealy.ThepossibilityofscreeningthroughoutthisareavariesfrommoderateinthesouthernportionaroundChulitna,tominimalintheBroadPassandtheupperandlowercanyonsoftheNenanaRiver.Scenicqualitywillbeimpacted,theimpactbeingafunctionofexistingscenicqualityandtheopportunityforscreening.Impactinthe-NenanaCanyonwillbehigh;impactonBroadPasswillbemoderatetohigh;impactelsewherewillbemoderate.Twofavorablefactorsmitigatetheimpactsomewhat:1)ThecorridorisnotvisuallyintactastheAlaskaRailroadandtheAnchorage-FairbanksHighwayhavealreadyreducedscenicqualitysomewhat.2)Thetr.ajorviewssouthofthecanyonsaretothewest,towardtheMt.McKinleymassif,whereasthecorridorliestotheeastofthetransportationroutes,themostlikelyviewpoints.(SeeMitigatingMeasures.) LandUseandResources:TheNenana-lcorridorfollowsexistingcorridorsforits.entirelength.For10milesitfollowstheAlaskaR.ailroadfromGoldCreek.FromnorthofChulitnatoEsteritfollowsacombinedRailroad/Highway.corridor.FromHealynorthitalsoparallelstheGoldenValleyElectricAssociation138kvtransmissionline.Itispossiblethecorridorcouldadjointhisright-of-wayortheGVEAlinecouldberebuilttoahighercapacityandtheexistingright-of-wayutilized.AlthoughthepotentialforagricultureexistsalongthiscorridorintheTananaValleyportion,itexistsintheformofhomegardensandgrazingifatall.Impactonexistingandpotentialagricultureislowtonone.Someforestryexistsinthebottomlandspruce-poplarforestsalongthelowerNenanaRiverandtheTananaRiver.Possiblesalesofmerchantabletimberfromtheclearinginthisareawillbringshort-livedbusinesstothetownofNenana,butthisimpactwillbelow.Useoftheaccessroadasaloggingroadandfirebreakmayoccur,butthisusewillnotsignifi-cantlyaffectlogginginthisarea.Althoughthecorridorapproachesandcrossesseveralmineralizedareasandfossilfueldeposits,itwillnotmakepowerdirectlyavailablefordevelopmentexceptthroughdistributionsystemsoftheexistingelectricutilities.Theaccessroadmaybeusedasaprospectingroad,butwillnotserveforheavieruse.Thevalueofthemineralsandfuelissuchthatifaprofitableareaweretobedeveloped,itwouldbefeasibletorelocatesmallsectionsofthetransmissionline.Onthewhole,impactenexistingandpotentialmineralandfuelextractionislow.Slightlymorethanhalfofthelengthofthiscorridorpassesthroughthe1H.McKinleyCooperativePlanningandManagementZoneofEcologicalConcern.ThisisastudyareaofajointState-FederalPlanningandManagementCommitteeresponsibleforlanduseplanningintheareaperipheraltotheMt.McKinleyNationalPark.Social:Thesetownswillbeaffectedbythecorridor:Cantwell,Healy,Nenana,andFairbanks.Cantwellisasmallcommunitywithnoelectricutility,andfewservicesapartfromarailroadstationandafewrestaurant/motel/gasstations.IncomingmaterialmayarriveattheAlaskaRailroad;possiblecongestionofthestationmayoccur.Thisisaninsignificantimpact,however,andquitetemporary.ItispossiblethatCantwellwilltapdirectlyfromthe230kvtransmissionline.AppendixI1-43 Appendix11-44Electricalservicewilleitherbeviafuturedistributionlinesofoneoftheexistingutilitiesorbytappingfromanewsubstation.Theproposed25kvdistributionlinetoMcKinleyParkmayeventuallyextendsouthtoserveCantwellandSummit.Ifthetransmissionlineisconstructedfirst,pressureisexpectedtobegreaterforasubstationtoserveCantwellandSum1T.it.Thepresenceofanearbytransmissionlinewillundoubtedlyresultinincreasedpressurefromthecommunityforelectricalservice;althoughwhichofthetwomethodswillbedeterminedbythecostandfeasibilityofboth.HealyissimilartoCantwell,exceptthatitisservedbytheGVEAsystemISHealysteamplant.Nenanaisafairlyimportanttransportationnode,situatedatthecrossingoftheTananaRiver,anavigablewaterway,bytherailroadandhighwaycorridors.Situatedinabottomlandspruce-poplararea,ifthetimberfromalineclearingistobesold,thenthelogswillpassthroughNenana,offeringsomebusinessandjobs.ItisunlikelythatmuchlaborfortheactuallineconstructionwillbedrawnfromNenana.ThetownisalreadyservedbytheGVEAsystem.TheexistingHealy138kvlinepassesveryclosetothetown.ForashortstretchitusesshortertowersandspanstominimizehazardstoaircraftusingtheFAAstripsouthoftown.Thecorridorwillbefarenoughfromtheairstriptoreducethishazardtoaminimum,and anyspansdeemedhazardousbytheFAAwillbemarked.ImpactsofAlternativeSusitna-2AlternativecorridorSusitna-2duplicatesSusitna-lfromPointMacKenzietoTalkeetna.Impactsareidenticalforthissegment,andarediscussedunderimpactsofpreferredcorridorSusitna-l,ImpactsdiscussedhereareforthesegmentfromTalkeetnatoGoldCreekviaTroublesomeCreek.Soils:Inthesouthernportionofthisalternativethereisahighproportionofpoorlydrainedsoilswhichcanbeexpectedtopresentproblemsfortowerfootingsandaccessroads.Theseverityoftheproblemwilldependuponthevulnerabilityofthesoiltofrostheavingandtheabilityofthefinallinesurveytoavoidareasofpoorsoils.IntheuplandareasaroundTroublesomeCreek,gravellysoilswillpresenterosionalproblems,particularlysincesteeperslopesareencountered.Frostheavingshouldbelessofaconcern,andmaintenanceoffootingswillbeless.Therewillbelittleornoproblemwiththermaldisruptionofpermafrostasthereisonlydiscontinuous,deeplyburiedpermafrostalongthisalternative.However,finallinesurveycanlocateandavoidanyhighl"iskareas.Thermaldisruption,particularlyintheuplandareas,couldleadtogulleyingandotherformsoferosion. CrossingsoftheTalkeetnaandSusitnaRivers,parallelingofWhiskersCreek,andapossiblecrossingofTroublesomeCreekarenecessary.FordingoftheTalkeetnaandSusitnaRiversisunlikely.Inanyevent,theriversarebothalreadysedimentladenriversandwillbelittleaffectedbyadditionalsediment.SedimentwillnegativelyimpactfishhabitatintheWhiskersandTroublesomeCreeks,bothofwhichareclearwaterstreams.Vegetation:TheamountofclearingfortheSusitna-2alternativeisupto2,375acres,67acresmorethanthatforSusitna-1,ifthelineistobe345kv.A230kvlinewouldrequireupto2,121acres,61morethanasimilarlinealongSusitna-1.Theactualacresofclearingwillprobablybelessthanthesefiguressincesomestretchesmayonlyrequireclearingfortheaccessroadandthetowerbases.Inthesouthernportiontheterrainisflatenoughsothattheclearingwillincludetheaccessroad;inthesteeperterraintheaccessroadmayhavetodeviatefromtheright-of-waytomaintaingrade,andthiswillrequireadditionalclearing.Theimmediateeffectofthisclearingwillbethedestructionofthevegetation.Themuchmoresignificantimpactwillbeuponerosionandwildlifehabitats.Inhillyterrain,mechanicalclearingmethodssuchasbulldozingwillcauseconsiderabledisruptionofthesoil,andsubsequenterosionandstreamsedimentation.Theuseofbrushbladesorrotarycutterswillreducethiseffect.Onsteepslopeshandclearingwillmitigatetheotherwiseheavyerosionpotentiallikelywithmechanicalclearing.Toreduceavailablefuelforforestfires,andtoreducepotentialinfestationofhealthytreesbysprucebeetles(Dendroctonusrufipennis)andipsbeetles,slashmustbedisposedof.Thiscanbeeitherbysaleofmerchant-abletimberorbyburning.Althoughburningwillreduceairqualitytemporarily,itismoreeconomicalandlessdamagingthanthealternatives.(SeeMitigatingMeasures.)Regrowthratesalongthiscorridorarefastenough,particularlyinthesouthernportion,towarrantperiodicsuppressionoftallgrowingtreeswhichposeahazardtothetransmissionline.Thepreferredmethodalongthiscorridorismanualapplicationofasuitableherbicide.Theamountofclearingtobemaintained,themodestregrowthrates,andhighcostoflabormakethisalternativepreferableinthiscorridoroveraerialapplicationofherbicidesontheonehand,orhandcuttingofindividualtreesontheother.Ifproperapplicationtechniquesareadheredto(seeMitigatingMeasures),therewillbenootherimpactsotherthanthemaintenanceofasub-climaxvegetation.Accidentaloversprayingorwinddrift,orimproperdilution,resultinginunnecessarydestructionofvegetationandsprayingofwaterbodiesresultinginhabitatdestructionAppendixI1-45 AppendixI1-46foraquaticlifearenotlikelytooccurwithmanualapplication.Sectionsneedingvegetationsuppressionoccursinthebottomlandspruce-poplar,lowlandspruce-hardwood,anduplandspruce-hardwoodforests,particularlyinthebottomlandspruce-poplarandmuskeg-bogareas,whichcompriseasignificantproportionoftheecosystemscrossedbythiscorridor,willneedlittleclearingandnovegetationsuppression.Lowlandspruce-hardwoodareaswillnotneedtobemaintainedasoftenasbottomlandspruce-poplar.Wildlife:Alterationofvegetationpatternswillaffectwildlife.Thiscorridortraversesmanyareasofmooseconcentration,andmooseshouldbenefitfromtheintroductionofbrushresultingfromtheregrowthontheclearing.Sincetheclearingmustbemaintained,thisbrushareawilllastforthelifeoftheline.Mostbrushareasareintransition,changingfromthebrushphasetosomeotherphaseapproachingtheclimacticphase.Thebrushinatransmissionclearingcanbecountedasamorepermanentsourceofbrowse.Animalsdependentuponclimacticforest,suchassquirrels,willsufferlossanddisplacement.However,theirfasterreproductiverateswillallowtheirpopulationstoadaptrapidly.Mostanimalswillbenefitfromtheedgeenvironment,offeringbothforageandcoverfromtheadjacentforestandbrush.Initially,anin:almovementsmayoccuralongtheright-of-way,butasthebrushgrowsintoadensecover,thiswillbelimited.Inanyevent,thisimpactshouldbelowinthiscorridor.Constructionitselfwillaffectwildlife.Largermammalsmaytemporarilyleavetheareatoreturnaftertheconstructionactivity.Smalleranimalswillsufferlossofindividuals,butshouldrecuperaterapidlyonceconstructioniscompleted.Thedensityofforestinthiscorridorwillallowanimalstomoveonlyashortdistancetoavoidcontactwithconstructionactivities.Vegetationsuppression,bywhatevermethod,willperiodicallyremovecoverfromalongtheright-of-way.However,duetothesurroundingcoveroftheunclearedforests,thisimpactwillbeinsignificant.Recreation:Thiscorridorpenetrates26milesoftheDenaliStatePark,comingwithin4milesoftheAnchorage-FairbanksHighwaynearthePark'ssouthernborder.ThisputsthecorridorwithineasywalkingdistanceofthehighwayforasignificantpartofitslengthwithinthePark.Thiswillaffectpresentandpotentialtrailsintersectingthecorridor. AccessibilitytotheParkwouldbeincreasedbythecreationofanaccessrouteparalleltothehighway;however,thehighwayandtheSusitnaRiverarenotseparatedmorethannineorlessthanfourandahalfmiles,sothecorridor,whichseparatesthetwo,willnotserviceaninaccessiblearea.HuntingispresentlyprohibitedinDenaliStateParksoanaccessroadwillhavenovalueashuntersIaccess.ImpactonrecreationwillbenegativesincetheentireareaoftheParktotheeastofthehighwaywillbelimitedforhikinganddaytrails.CulturalResources:TheNationalRegisterlistsnohistoricalorarcheo-logicalsitesalongthiscorridor.Ifthefinalroutesurveylocatesanarcheologicalsite,minorrelocationorcarefultowerlocationwillavoiddisruptionofthesite.Inadvertantdisruptionofanarcheologicalsitewillreduceordestroyitsarcheologicalvalue.ScenicResources:Thetransmissionlinecanbeeffectivelyhiddenfromthehighwayforitsentirelength;however,itsimpactisstillhighbecauseofconflictswiththeexistingandpotentialtrailsintheStatePark.Asignificantvalueofthesetrailsisaesthetic,andvisibilityofatransmissionlinefromaninterceptedoradjacenttrailwillseriouslydetractfromtheoriginalpurposeofthesetrails.LandUseandResources:Themajorlanduseofthissegmentisscenicandrecreational.Impactsareasdescribedaboveunder"Recreation"and"ScenicResources,IITherewillbenosignificantimpactonforestryoragriculturebecauseoftheexclusivenatureoftheStateParklanduse.Therewillbenoimpactsonotherresourcesinthissegment.ImpactsofAlternativeSusitna-3Soils:Thesoilsencounteredalongthisalternativearebasicallywellsuitedtotheconstructionofanaccessroad,Thelowerosionpotential,absenceofsignificantpermafrost,andthegravellytextureindicatethateffectsoferosionandconsequentsedimentationwillbelow,Dependinguponthefinalroutesurvey,severalsmallclearwatercreekswillbecrossed,Somesedimentationwilloccurfromfordingofconstruc-tionequipment.Thissedimentationwillbeofatemporarynature,andoflowsignificancesincethisuplandareaisnotanimportantfishery,TheTalkeetnaRiverwillneedatleastonecrossing,butprobablywillnotbeforded.SincetheTalkeetnaRivercarriesaglacialsiltload,anyadditionalsedimentationwillnotbesignificant.AppendixI1-47 AppendixI1-48Theuplandsoilsarequiteshallow;excavationoffootingsmayrequireblasting.Accessroadlocationmayhavetodeviatefromthetransmissionlineinordertokeepanacceptablegradewithoutextensiveexcavation.Vegetation:TheSusitna-3alternativefor345kvcouldrequireupto1,900acres,407acreslessthanthatforSusitna-1.For230kv,thisalternativewouldrequireupto1,696acres,364acreslessthanasimilarlinealongcorridorSusitna-1.ThemajorityofthisclearingwilloccurintheTalkeetnaRivervalley.LittleornoclearingwillberequiredintheuplandareastowardDevilCanyon.Theimmediateeffectofthisclearingwillbethedestructionofthevegetation.Themuchmoresignificantimpactwillbeuponerosionandwildlifehabitats.Inhillyterrainmechanicalclearingmethods,suchasbulldozing,willcauseconsiderabledisruptionofthesoilandsubsequenterosionandstreamsedimentation.Theuseofbrushbladesorrotarycutterswillreducethiseffect.Onsteepslopes,handclearingwillmitigatetheotherwiseheavyerosionpotentiallikelywithmechanicalclearing.Toreduceavailablefuelforforestfiresandtoreducepotentialinfestationofhealthytreesbysprucebeetles(Dendroctomusrufipennis)andipsbeetles,slashmustbedisposedof.Thiscanbeeitherbysaleofmerchant-abletimberorbyburning.Althoughburningwillaffectairqualitytempo-rarily,itismoreeconomicalandlessdamagingthanthe·alternatives.(SeeMitigatingMeasures.)Regrowthratesalongthiscorridorarefastenough,particularlyinthesouthernportion,towarrantperiodicsuppressionoftallgrowingtreeswhichposeahazardtothetransmissionline.Thepreferredmethodalongthiscorridorismanualapplicationofasuitableherbicide.Theamountofclearingtobemaintained,themodestregrowthrates,andhighcostoflabormakethisalternativepreferrableinthiscorridoroveraerialapplicationofherbicidesontheonehandorhandcuttingofindividualtreesontheother.Ifproperapplicationtechniquesareadheredto(seeMitigatingMeasures),therewillbenootherimpactsotherthanthemain-tenanceofasub-climaxvegetation.Wildlife:Alterationofvegetationpatternswillaffectwildlife.ThiscorridortraversesmanyareasofmooseconcentrationintheTalkeetnaRivervalley,andmooseshouldbenefitfromtheintroductionofbrushresultingfromtheregrowthontheclearing.Sincetheclearingmustbemaintained,thisbrushareawilllastforthelifeoftheline.Most brushareasareintransition,changingfromthebrushphasetosomeotherphasenearertheclimacticphase.Thebrushinatransmissionclearingcanbecountedasamorepermanentsourceofbrowse.Animalsdependentuponclimacticforest,suchassquirrels,willsufferlossanddisplacement.However,theirfasterreproductiverateswillallowtheirpopulationstorecuperaterapidly.Mostanimalswillbenefitfromtheedgeenvironment,offeringbothforageandcoverfromtheadjacentforestandbrush.Initially,animalmovementsmayoccuralongtheright-of-way,butasthebrushgrowsintoadensecover,thiswillbelimited.Thisimpactshouldbelowinthiscorridor.Theremaybeapossibleimpactonthecaribouwinterrangereportedtoexistin intheuplandareasalongthisalternative.Summerconstruc-tionwillreducecontactsofcaribouandtheconstructionactivity.Firesstartedbyconstructionmaydestroypotentialwinterbrowse.Thedegreeofthisimpactdependsupontheareaburnedandtheseasonoftheburning.Largermammalsmaytemporarilyleavetheareatoreturnaftertheconstructionactivity.Smalleranimalswillsufferlossofindividuals,butshouldrecuperaterapidlyonceconstructioniscompleted.Thedensityofforestinthiscorridorwillallowanimalstomoveonlyashortdistancetoavoidcontactwithconstructionactivities.Vegetationsuppression,bywhatevermethod,willperiodicallyremovecoverfromalongtheright-of-way.However,duetothesurroundingcoveroftheunclearedforests,thisimpactwillbeinsignificant.Herbicideswillnotdirectlyaffectanimalsinthedilutionsusedformanualspraying;herbicidesusedonright-of-waymaintenancearenon-cumulativeandarereadilyexcreted.Theoveralladverse.impactofherbicidesprayingwillbelow,asitwillbenecessaryonlyeveryfivetotenyears,whereastheavailabilityofforageprovidedisaspermanenta.sthetransmissionline.Recreation:Thiscorridorapproachesnorecognizedrecreationarea.SincetheentirelengthofthissegmentfromTalkeetnatoDevilCanyonparallelsnoexistingtransportationline,asizeableamountoflandisopeneduptoaccessbyfour-wheeldrivevehicles,dependentuponthepoliciesofthelandownersormanagingagency.Forrecreationrequiringvehicularaccess,thisincreasedaccesswillhaveabeneficialimpact.Forrecreationdependentuponprimitivevalues,increasedaccesswillhaveadetrimentalaspect.AppendixI1-49 AppendixII-SOCulturalResources:Thereisnoknownimpactonculturalresourcesinthissegment.ScenicResources:Intermsofviewercontacts,thiscorridorwillhavealowimpactonscenicqualityduetoitsrelativeinaccessibility.How-ever,thiscorridorwillhaveahigherimpactupontheintactnessofthisareathanthecomparablesegmentsofSusitna-landSusitna-2.Thehighprimitivevaluesandmediumtohighscenicvalueofthiscorridor,coupledwithrelativelyhighvisibilityofatransmissionlineintheuplandarea,willresultinahighimpactonscenicquality,dis-regardingthefactorofviewercontacts.LandUseandResources:NoimpactonagricultureisanticipatedalongthiscorridorfromTalkeetnatoDevilCanyon.AnaccessroadwillnotenhanceforestryintheTalkeetnaRivervalleysinceitwouldbeunsuit-ableforaloggingroadunlessitwereoverbuilt,andsincetheaccessroadwouldrunveryclosetothetransmissionlineitself.Impactsonmineralresourceswillalsobelow;notenoughpotentialexistsalongthecorridortobeinfluencedbytheincreasedaccess.Social:Nocommunitiesareencounteredalongthiscorridor;sothereisnoimpact.ImpactsofAlternativeSusitna-4Soils:ForsoilsintheportionofthiscorridorthatfollowstheTalkeetnaRiverandPrairieCreek,impactsfromerosion,siltation,andpermafrostdegradationarelow.CrossingsoftheTalkeetnaRiverandIronCreekwillbenecessary.Bothofthesestreamsaresedimentladen;soaddi-tionalsedimentationwillhavelittleeffect.Thesoilsontheuplandportionofthiscorridoraremoresusceptibletoerosion,althoughtheslopesareshallower.Animproperlyconstructedaccessroadwillcauseerosion.Veryfewcreeksarecrossed.Sedimentationwouldbeaveryminorproblem.Somepermafrostassociatedwithpoorlydrained,peatysoilsmaypresentproblems,notonlyofpermafrostdegradation,butoffrost-heaving.However,finallinesurveyshouldreducethispotentialimpact.Unavoidablestretchesofpoorlydrainedsoilsmayberuttedandscarredbyvehicletracksunlesstheaccessroadishardenedwithagravelbed.Vegetation:Fora345kvlinethiscorridorcouldrequireupto2,257acresofclearing,50acreslessthanSusitna-l.Fora230kvdesignitwouldrequireupto2,105acres,45acreslessthanasimilarlineon Susitna-l.Actualacreagesofclearingwillprobablybelessthanthesefiguressincetheentireright-of-waywillinmostcasesnotbecleared,andalongsomestretchesonlytheaccessroadandtowerbasesneedtobecleared.Theimmediateeffectofthisclearingwillbethedestructionofthevege-tation.Themuchmoresignificantimpactwillbeuponerosionandwild-lifehabitats.Inhillyterrain,mechanicalclearingmethodssuchasbulldozingwillcauseconsiderabledisruptionofthesoilandsubsequenterosionandstreamsedimentation.Theuseofbrushbladesorrotarycutterswillreducethiseffect.Onsteepslopes,handclearingwillmitigatetheotherwiseheavyerosionpotentiallikelywithmechanicalclearing.Toreduceavailablefuelforforestfiresandtoreducepotentialinfesta-tionofhealthytreesbysprucebeetles(Dendroctonusrufipennis)andipsbeetles,slashmustbedisposedof.Thiscanbeeitherbysaleofmerchantabletimberorbyburning.Althoughburningwillaffectairqualitytemporarily,itismoreeconomicalandlessdamagingthanthealternatives.(SeeMitigatingMeasures.)RegrowthratesalongtheTalkeetnaRivervalleyarehighenoughsothatperiodicsuppressionoftallgrowingtreeswithintheclearingisrequired.Themethodtobeusedwillbemanuallyappliedherbicide,appliedtotargettreesduringregularmaintenancepatrols.Ifproperlyapplied,therewillbenocontaminationofwaterbodiesordestructionofnon-targetvegetation.Themostimportantimpactofthisprogramwillbethemainte-nanceofsub-climaxbrushwithinforestedareas.Wildlife:Alterationofvegetationpatternswillaffectwildlife.ThiscorridortraversesanareaofmooseconcentrationintheTalkeetnaValley,andmooseshouldbenefitfromtheintroductionofbrushresult-ingfromtheregrowthontheclearing.Sincetheclearingmustbemaintained,thisbrushareawilllastforthelifeoftheline.Mostbrushareasareintransition,changingfromthebrushphasetosomeotherphasenearertheclimacticphase.Thebrushinatransmissionclearingcanbecountedasamorepermanentsourceofbrowse.Animalsdependentuponclimacticforest,suchassquirrels,willsufferlossanddisplacement.However,theirfasterreproductiverateswillallowtheirpopulationstoadaptrapidly.Mostanimalswillbenefitfromtheedgeenvironment,offeringbothforageandcoverfromtheadjacentforestandbrush.Initially,animalmovementsmayoccuralongtheright-of-way,butasthebrushgrowsintoadensecover,thiswillbelimited.Inanyevent,thisimpactshouldbelowinthiscorridor.AppendixII-51 AppendixII-52Constructionitselfwillaffectwildlife.Largermammalsmaytemporarilyleavetheareatoreturnaftertheconstructionactivity.Smalleranimalswillsufferlossofindividuals,butshouldrecuperaterapidlyoncecon-structioniscompleted.Thedensityofforestinthiscorridorwillallowanimalstomoveonlyashortdistancetoavoidcontactwithconstructionactivities.Vegetationsuppression,bywhatevermethod,willperiodicallyremovecoverfromalongtheright-of-way.However,duetothesurroundingcoveroftheunclearedforests,thisimpactwillbeinsignificant.Herbi-cidesappliedasoutlinedunder"Vegetation,"willproducefeweffectsuponanimals.Sincetheherbicidesareappliedonlytotargetvegeta-tion,theprobabilityofingestionisreducedtoaminimum.Herbicidesarenottoxictoanimalsintheconcentrationsnormallyused,andarenotcumulativeineffect.Recreation:AlthoughthiscorridordoesnotapproachanyStateOrFederalrecreationareasorparks,itwillaffecttherecreationaluseoftheuplandareanearStephenLake.Readilyaccessiblebyfloatplane,thisareaispopularwithsportsmenandvacationers.Thelakeshavemanycabinsalongtheirshores.Theaccessroadwouldprovideanothermeansofaccessforthisarea,whichwouldtendtoincreasetherecrea-tionaluse,andatthesametime,thetransmissionlinewouldbevisibleformostofitslengthovertheuplandarea.Ifoneoftheperceivedvaluesofthisareaisitsrelativeinaccessibility,thenincreasedaccessandavisibletransmissionlinewouldhaveahighlydetrimentalimpact.Increasedaccessibilitytootherareastraversedbythecorridorwouldbebeneficialtorecreationalusedependentuponeasyaccess.CulturalResources:Ifthefinalsurveydisclosesanunsuspectedarcheologicalsitealongtheright-of-way,thelocationofthelineortowerswillbealteredtoavoiddamagetosuchsites.Inadvertentdamagetoanarcheologicalsitewillreduceitshistoricalvalue.Atthesametime,discoveryofanarcheologicalsiteduringsurveyorconstructionwillbeabeneficialaspect.ScenicResources:Intermsofviewercontacts,impactofatransmissionlinealongtheTalkeetnaRivervalleywillbelow.Alongtheuplandareaitwillbehigh.Thisareaisaheavilyusedrecreationarea,sparselyforested,andofmoderatetohighscenicquality.Thus,theconstructionofatransmissionlineandtheinherentvisibilityofsuchalinewouldresultinahighimpact. LandUseandResources:Therewillbesignificantimpacts,bothbene-ficialanddetrimental,onthepredominantlanduse,recreation.TheseimpactsarediscussedunderthelfRecreationlfsectionabove.Therewillbenoimpactonagriculture,forestry,andmineralresources.Social:Therewillbenosocialimpactsfromthiscorridor.ImpactsofAlternativeNenana-2Soils:Impactsonsoilsalongthiscorridorwillbeidenticaltothoseout-linedinNenana-luptoCantwell.Thegenerallyflat,gravellysoilfromCantwelltoWellsCreekisvulnerabletowatererosion.Constructionactivitiesmaycausegulleyinginthisarea.Thepeatypermafrostsoilsalsofoundinthisareawillpresentproblemsinconstructingtheaccessroad.Possibleruttingandscarringmayleadtodegradationoftheunder-lyingpermafrostandfurthererosion.FromWellsCreektotheupperWoodRiver,impactswillvarywiththetypeofsoilencountered,whichcanbelocalizedpoorlydrainedfrozensoil,thinsoilsandgravel,andbarebedrockandtalus.Localpocketsofpoorlydrainedsoilscanbeavoidedtoanextent.Unavoidableencounterswillresultindisturbanceofthesoilandpossibleconsequentdisruptionofthepermafrost.Thinsoilsandgravelareverysusceptibletoerosion.particularlysincetheywillbefoundinconjunctionwithsteepslopes.Accessroadconstructionwillhaveadetrimentalaffectinboththesesoils.Noimpactonbarebedrockandtalusisanticipated;however,footingsfortowerswillrequireblastingandconstructionofanaccessroadwillbeextremelydifficult.Increasingamountsofpoorlydrained,frozen,peatysoilsencounteredfromalongthelowerWoodRivertotheTananaRiverwillcauseincreasingproblemswithaccessroadconstruction,footingstabilization,andruttingandscarringofthesoils.Unlesstheaccessroadisbeddedongravel,thereisastrongpotentialforpermafrostdegradationandconsequentgulley-ingandmaintenanceproblems.ImmediatelyadjacenttotheTananaRiver,stratifiedsoilspresentapotentialwatererosionproblem,yetareeasiertoconstructonthanthesurroundingpoorlydrainedpeats.Thesestrati-fiedmaterialsareoftenleveesofextinctorexistingchannels.Theyarelinear,butsinuous,andmayprovidenotonlythebestfoundationforaroad,butalsothehighestpointabovefloodwaters.AppendixII-53 Appendix11.,.54Theimpactofsedimentationonglacialriverswillbelow.SedimentationimpactonclearwaterstreamswillbemediumforWellsCreek,LouisCreek,andDeanCreek.SedimentationimpactsuponthenumerousclearwatertributariesoftheWoodRiverwillbelowsincetheywillbecrossedclosetotheirconfluenceswiththesiltladenWoodRiver.Vegetation:ThiscorridorcouldrequireuptoI,500acresofclearing,60acresmorethanthatforNenana-I.Actualacreageclearedwillprobablybelessthanthisfiguresincetheentireright-of-wayneednotbecleared,andtheterrainrequiringtheheavierclearingisgenerallyflatenoughtoallowtheaccessroadtorunwithintheclearing.Theimwediateeffectofthisclearingwillbethedestructionofthevege-tation.Themuchmoresignificantimpactwillbeuponerosionandwildlifehabitats.Inhillyterrainmechanicalclearingmethodssuchasbulldozingwillcauseconsiderabledisruptionofthesoilandsubsequenterosionandstreamsedimentation.Theuseofbrushbladesandrotarycutterswillreducethiseffect.Onsteepslopes,handclearingwillmitigatetheothelowiseheavyerosionpotentiallikelywithmechanicalclearing.Toreduceavailablefuelforforestfiresandtoreducepotentialinfesta-tionofhealthytreesinthebottomlandspruce-poplarecosystembysprucebeetles(Dendroctonusrufipennis)andipsbeetles,slashmustbedisposedof.Thiscanbedonebysaleofmerchantabletimber,bychipping,orbyburning.Althoughburningwillaffectairqualitytemporarily,itismoreeconomicalandlessdamagingthanthealternatives.Withnoaccessroad,machinerycannotbebroughtinforstacking,burning,orchipping,anddownedtimberwillbeleftalongtheclearing.(SeeMitigatingMeasures.)Exceptforthebottomlandspruce-poplarforestalongtheTananaRiver,regrowthratesarelowenoughsothatlittlevegetationsuppressionotherthanroutinetrimmingofdangertreesisnecessary.MoreextensivecuttingprogramsmaybenecessaryintheareaaroundtheTana.naRiver.Inthemoisttundraandalpinetundraecosystems,disturbedareaswillbeveryslowtorecuperate.Revegetationwithappropriatespecieswillbenecessarytominimizesurfaceerosionandpermafrostdegradation.Properconstructionandaccessroaddesignwilllimitvegetationlosstotheareaoccupiedbytheroadbedandtowerbases.Noclearingisnecessaryintheseareas.Firescausedbyconstructionandmaintenancewillhavelittleimpact,providingtheyarediscoveredquicklyandstoppedwithoutexcessdisturb-anceofthesoil.Thepresentpatternsofforestsarecausedbypreviousnaturallycausedfireswhichareanintegralfactorofthese ecosystems.Impactfromasmallnumberofadditionalfiresoflimitedareawillbelow.Wildlife:Thegreatestanticipatedimpactuponwildlifewillbethealtera-tionofvegetativepatterns,andthisimpactwillbeafunctionofthedegreeofclearing.Animalsdependentuponclimaxforestwillsufferlossofindividualsandlossofhabitat.Generally,thesearethesmallmammalssuchassquirrelandmarten.Moosewillbenefitfromthecreationofanareaofmaintainedbrowse.Sincetheclearingwillnotbeallowedtotalregrowth,thebrowsecreatedcanbeconsideredaspermanentastheline.Theconjunctionofforestandopenbrushcreatesafavorable"edge"environmentformostanimals,offeringforageontheclearingandcoverintheforest.Constructionactivitywilltemporarilyfrightenawaywildlife;however,thisisanextremelylocalandtemporaryimpact.Maintenancepatrolswillnotbefrequentenoughtokeepanimalsfromreturningtothecorridor.ImpactuponthecaribouwinteringrangesoneithersidesoftheAlaskaRangewillbelowifconstructionisdoneinsummer,whichmaybepre-ferrableinanycasebecauseofbetterworkingconditions.Dallsheephabitatwillbeimpactedinthattheywillbefrightenedawayfromcon-structionactivitymoresothancaribouandmoose.Again,thisimpactisofatemporarynature.Uncheckedfireineitherofthesehabitatswilladverselyimpactbothcaribouandsheep.Withcaribouparticularly,destructionoftheirkeywinterbrowse,lichen,mayhavelonglastingeffectsduetoslowregrowthrates.Recreation:ThiscorridordoesnottraverseanyFederalorStateparksorrecreationareas.Itdoes,however,brieflyapproachwithinfivemilesthesoutheastcornerofMcKinleyNationalPark.Exceptfor22milesalongtheDenaliHighway,thecorridorwillprovideaccesstoanareapreviouslyaccessibleonlybyairorfoot.Insomecases,accessispresentlypossiblewithall-terrainvehicles.Increasedaccesswillimpactgameanimalpopulationssomewhat;theactualimpactwilldependuponthedesirabilityoftheareaforhunting,andaccessandhuntingregulationsimposedbythelandmanagingagencies.CulturalResources:ThisalternativeapproachesnoNationalHistoricorArcheologicalSites.Ifthefinalsurveydisclosesanunsuspectedarcheologicalsitealongtheright-of-way,thelocationofthelineorAppendixII-55 AppendixII-56towerswillbealteredtoavoiddamagetosuchsites.Inadvertentdamagetoanarcheologicalsitewillreduceitshistoricalvalue.Atthesametime,discoveryofanarcheologicalsiteduringsurveyorconstructionwillbeabeneficialaspect.ScenicResources:Thisalternativetraversesareasoflowtohighscenicquality.Intermsofviewercontacts,thiscorridorwillhavelittleimpactsinceitwillnotbevisiblefromtransportationroutesformostofitslength.Disregardingviewers,highvisualimpacttoscenicandwildernessqualityinthemountainousportionofthecorridorcanbeexpected.LandUseandResources:Therewillbenoimpactsonforestryandagriculturethroughoutthisalternative.Therewillbenoimpactsonmineralorfossilfuelresources.Apartfromobtainingeasements,noimpactisexpectedonexistinglanduse.ImpactsofAlternativeNenana-3Soils:ThemajorityofthesoilsontheportionofthisalternativewhichdiffersfromtheproposedNenana-1corridorarerocky,thinsoilsandbedrock,andassucharewellsuitedgenerallyfortowerfoundations.Accessroadconstructionwillbehamperedbysteepslopes,bedrock,andtalusencounteredbythiscorridor.Erosionwillgenerallybelow,althoughonthinsoilsorunstableslopes,erosionwillbesevereunlesscorrectivemeasuresareemployed.Permafrostcanbeassumedtobecontinuous,butwillnotusuallybeofconcerntotowerlocationunlessthesoilisice-rich.Thisconditionisassumedtoberestrictedtovalleyfloors.Soilimpactsfortheremainderofthealternativearedescribedundersoilimpactsoftheproposedcorridor.Vegetation:TheNenana-3corridorcouldrequireupto1,318acresofclearing,121acreslessthanNenana-I.AlmostnoclearingisneededontheportionwhichdiffersfromtheNenana-1corridorsincemostlyalpineandmoisttundraecosystemsareencounteredinthisportion.ImpactsresultingfromclearingwillbesimilartothosediscussedunderNenana-I.Alongthedifferingsegmentdestructionofvegetationwillbelimitedtothoseareasdirectlyoccupiedbythe"roadbedandthetowerbases.Thiswillbeapermanentimpact,althoughsomerevegetationoftowerbasescanbeexpected. Destructionofthevegetativematintundraareaswillresultinlonglastingscarsunlesscorrectiveandpreventivemeasuresaretaken.Thisscarringcouldleadtosubsequentdegradationofice-richpermafrostanderosion.Firesresultingfromconstructionandoperation,unlesssuppressedquickly,willresultinextensivedestructionofvegetation.Theseecosystemsareadaptedtonaturalwildfires,andunlesstheoccurrenceofman-causedfiresisveryhigh,theyshouldrecuperateasquicklyastheywouldundernormalcircumstances.Wildlife:ImpactsonwildlifeforthosesegmentsofthisalternativecorridortoNenana-larediscussedunderimpactstowildlifeoftheproposedcorridor.Alongthedifferingsegment,therewillbelittleimpactfromhabitatmodificationduetoclearing.IncreasedincidenceoffireresultingfromoperationorconstructionwilladverselyaffecthabitatforDallsheepandcaribou.Moosehabitatwillbeenhanced,uptoapoint,byfire.Constructionactivitymaycauseavoidanceofthecorridorbyanimals;however,thisisatemporaryimpact.OperationandmaintenancewillnotaffecttheanimalsIoccupationofthecorridor.IncreasedaccessaffordedbytheaccessroadmayincreasehuntingpressureonDallsheep,caribou,andtoalesserdegreeonmoose.Thedegreeofthisimpactisdependentuponthedesirabilityofthiscorridorforhunting,andaccessandhuntingregulationsimposedbythelandmanagingagencies.Recreation:ThiscorridordoesnottraverseanyFederalorStateparksorrecreationareas.Itdoes,however,brieflyapproachwithin5milesthesoutheastcornerofMcKinleyNationalPark.Exceptfor22milesalongtheDenaliHighway,thecorridorwillprovideaccesstoanareapreviouslyaccessibleonlybyairorfoot.·Insomecases,accesSispresentlypossiblewithall-terrainvehicles.Increasedaccesswillimpactgameanimalpopulationssomewhat.Theactualimpactwilldependupondesirabilityof.theareaforhunting,andaccessandhuntingregulationsimposedbythelandmanagingagencies.CulturalResources:ThisalternativeapproachesnoNationalHistoricorArcheologicalSites.IfthefinalsurveydisclosesanunsuspectedAppendixII-57 AppendixII-58archeologicalsitealongtheright-of-way,thelocationofthelineortowerswillbealteredtoavoiddamagetosuchsites.Inadvertentdamagetoanarcheologicalsitewillreduceitshistoricalvalue.Atthesametime,discoveryofanarcheologicalsiteduringsurveyorconstructionwillbeabeneficialaspect.ScenicResources:Thisalternativetraversesareasofmoderatetohighscenicquality.Intermsofviewercontacts,thiscorridorwillhavelittleimpactsinceitwillnotbevisiblefromtransportationroutesformostofitslength.Disregardingviewers,highvisualimpacttoscenicandwildernessqualityinthemountainousportionofthecorridorcanbeexpected.LandUseandResources:Therewillbenoimpactsonforestryandagriculturethroughoutthisalternative.Therewillbenoimpactsonmineralorfossilfuel.resources.ImpactsofAlternativeNenana-4Soils:FromHealytoEster,thiscorridorduplicatesNenana-I,andimpactstosoilsareidenticaltothosediscussedunderimpactsofNenana-I.ThesoilsfromWatanaDamsitetoWellsCreekwillbeveryvulnerabletopermafrostdegradationandfrostheaving.Thevegetativematmustbepreserved,andconstructionactivitymustbeplannedtominimizedisruptionofthesoil.Erosioncausedbypermafrostdegradationandaccessroadconstructionwillhave<adverseimpactsonwaterqualityintheclearwaterstreamsencountered.Fordingofstreamsinthissegment,giventhesensitivesoilconditions,couldresultinextensivebankerosion.Tominimizethisandtoensuretheintegrityofthetransmissionline,thecorridorwillavoidrivercrossingswhenpossible.FromWellsCreektoHealyviaNenana-4,thesoilsarerocky,thinsoilsandbedrock,andassucharewellsuitedgenerallyfortowerfoundations.Accessroadconstructionwillbehamperedbysteepslopes,bedrock,andtalusencounteredbythiscorridor.Erosionwillgenerallybelow,althoughonthinsoilsorunstableslopes,erosionwillbesevereunlesscorrectivemeasuresareemployed.Permafrostcanbeassumedtobecontinuous,butwillnotusuallybeofconcerntotowerlocationunlessthesoilisice-rich.Thisconditionisassumedtoberestrictedtovalleyfloors. Vegetation:TheNenana-4alternativecouldrequireuptoI,182acresofclearing,257acreslessthanNenana-I.Actualacresclearedwillprobablybelessthanthissincetheentireright-of-wayneednotbecleared.ImpactsonvegetationfromHealytoEsterareidenticaltothosediscussedforthatsegmentunderimpactsofNenana-I.AlmostnoclearingisneededontheportionwhichdiffersfromtheNenana-lcorridorsincemostlyalpineandmoisttundraecosystemsareencounteredinthis.portion.Impactsresultingfromclearingwillbesimilartothosedis-cussedunderNenana-I.Alongthedifferingsegment,destructionofvegetationwillbelimitedtothoseareasdirectlyoccupiedbytheroadbedandthetowerbases.Thiswillbeapermanentimpact,althoughsomerevegetationoftowerbasescanbeexpected.Destructionofthevegetativematintundraareaswillresultinlonglastingscarsunlesscorrectiveandpreventivemeasuresaretaken.Thisscarringcouldleadtosubsequentdegradationofice-richpermafrostanderosion.Firesresultingfromconstructionandoperation,unlesssuppressedquickly,willresultinextensivedestructionofvegetation.Theseeco-systemsareadaptedtonaturalwildfires,andunlesstheoccurrencofman-causedfiresisveryhigh,theyshouldrecuperateasquicklyastheywouldundernormalcircumstances.Wildlife:ImpactsonwildlifeforthosesegmentsofthisalternativecorridortoNenana-larediscussedunderimpactstowildlifeoftheproposedcorridor.Alongthedifferingsegmenttherewillbelittleimpactfromhabitatmodi-ficationduetoclearing.IncreasedincidenceoffireresultingfromoperationorconstructionwilladverselyaffecthabitatforDallsheepandcaribou.Moosehabitatwillbeenhanced,uptoapoint,byfire.Constructionactivitymaycauseavoidanceofthecorridorbyanimals;however,thisisatemporaryimpact.OperationandmaintenancewillnotaffecttheanimalsIoccupationofthecorridor.IncreasedaccessaffordedbytheserviceroadmayincreasehuntingpressureonDallsheep,caribou,andtoalesserdegreeonmoose.TheAppendixII-59 AppendixI1-60degreeofthisimpactisdependentuponthedesirabilityofthiscorridorforhunting,andaccessandhuntingregulationsimposedbythelandmanagingagencies.Recreation:ThiscorridordoesnottraverseanyFederalorStateparksorrecreationareas.Thecorridorwillprovideaccesstoanareapre-viouslyaccessibleonlybyairorfoot.Insomecases,accessispresentlypossiblewithall-terrainvehicles.Increasedaccesswillimpactgameanimalpopulationssomewhat.Theactualimpactwilldependuponthedesirabilityoftheareaforhunting,andaccessandhuntingregulationsimposedbythelandmanagingagencies.CulturalResources:ThisalternativeapproachesnoNationalHistoricorArcheologicalSites.Ifthefinalsurveydisclosesanunsuspectedarcheologicalsitealongtheright-of-way,thelocationofthelineortowerswillbealteredtoavoiddamagetosuchsites.Inadvertentdamagetoanarcheologicalsitewillreduceitshistoricalvalue.Atthesametime,discoveryofanarcheologicalsiteduringsurveyorconstructionwillbeabeneficialaspect.ScenicResources:Thisalternativetraversesareasoflowtohighscenicquality.Intermsofviewercontacts,thiscorridorwillhavelittleimpactsinceitwillnotbevisiblefromtransportationroutesformostofitslength.Disregardingviewers,highvisualimpacttoscenicandwildernessqualityinthemountainousportionofthecorridorcanbeexpected.LandUseandResources:Therewillbenoimpactsonforestryandagriculturethroughoutthisalternative.Therewillbenoimpactsonmineralorfossilfuelresources.ImpactsofAlternativeNenana-5Soils:ThesoilsfromWatanaDamsitetoWellsCreekwillbeveryvulner-abletopermafrostdegradationandfrostheaving.Thevegetativematmustbepreserved,andconstructionactivitymustbeplannedtomini-mizedisruptionofthesoil.Erosioncausedbypermafrostdegradationandaccessroadconstructionwillhaveadverseimpactsonwaterqualityintheclearwaterstreamsencountered.Fordingofstreamsinthissegment,giventhesensitivesoilconditions,couldresultinextensivebankerosion.Tominimizethisandtoensuretheintegrityofthetransmissionline,thecorridorwillavoidrivercrossingswhenpossible. FromWellsCreektoupperWoodRiverthesoilsarerocky,thinsoilsandbedrock,andassucharewellsuitedgenerallyfortowerfoundations.Accessroadconstructionwillbehamperedbysteepslopes,bedrock,andtalusencounteredbythiscorridor.Erosionwillgenerallybelow,althoughonthinsoilsorunstableslopeserosionwillbesevereunlesscorrectivemeasuresareemployed.Permafrostcanbeassumedtobecontinuous,butwillnotusuallybeofconcerntotowerlocationunlessthesoilisice-rich.Thisconditionisassumedtoberestrictedtovalleyfloors.TheWoodRivervalleyandTananaRivervalleypresentproblemswithlocatingwelldrainedsoils.Largeareasofpoorlydrainedpeatswithcontinuousshallowpermafrostwillresultinpotentialsevereimpactssuchaspermafrostdegradation,ruttingandscarringofthesurface,bankerosionwhereclearwaterstreamsareforded,anderosioncausedbyaccessroadconstruction.Thenecessaryclearingwillalsogreatlyaddtoerosionandsiltation.Preventiveandcorrectivemeasureswillneedtobeusedtominimizetheseimpacts.Vegetation:Thiscorridorwillrequireupto1,369acresofclearing,74acreslessthanNenana-I.Actualacresclearedwillprobablybelessthanthisfiguresincetheentireright-of-wayneednotbecleal'ed,ThemajorityoftheclearingwillbealongtheTananaRivervalleyandlowerWoodRiverinthebottomlandspruce-poplaranduplandspruce-hardwoodecosystems.Alongthegreaterpartofthecorridortheaccessroadcanbeincorporatedintotheclearingduetolevelterrain.Themostimmediateeffectofclearingwillbethedestructionoftheclearedvegetation.Downedtimberandslashmustbedisposedofbyopenburningorchippingwhenpossibletopreventinfestationofstandingstocksofbottomlandspruce-poplarwithsprucebeetle(Dendroctonusrufipennis)andtheaccumulationoffuelforwildfire.Non-merchantabletimberwillbeburnedifanaccessroadispresent.Withnoaccessroad,machinerycannotbebroughtinforstacking,burning,orchipping,anddownedtimberwillbeleftalongtheclearing.Beetleinfestationwillbeofconcernmainlyinthebottomlandspruce-poplarecosystem.Destructionofthevegetativematintundraareaswillresultinlonglastingscarsunlesscorrectiveandpreventivemeasuresaretaken.Thisscarringcouldleadtosubsequentdegradationofice-richpermafrostanderosion,Firesresultingfromconstructionandoperation,unlesssuppressedquickly,willresultinextensivedestructionofvegetation,Theseeco-systemsareadaptedtonaturalwildfires,andunlesstheoccurrenceofman-causedfiresisveryhigh,theyshouldrecuperateasquicklyastheywouldundernormalcircumstances.AppendixI1-61 AppendixI1-62Somedisruptionofthesoilfromclearingistobee:h.'pected.Increasederosionbecauseofthis,andenhancedbythelackofcover,willresult.Ifvegetationiscleareduptoriverbanksonstreamcrossings,thismayresultinadditionalsedimentation.Wildlife:Therewillbelossofindividualsmalleranimalsanddisplace-mentofothers;however,thisisatemporarysetback.Highreproductiveratesofsmallmammalsandre-invasionwillamendthisimpact.Apermanenthabitatmodificationwillresultfromtheclearingandmainten-ance.Acorridorofbrushwillbemaintainedthroughotherwiseforestedland.Animalsdependentuponclimaxforest,suchassquirrels,willsuffersomehabitatloss.Animalsdependentuponbrushandforbsforbrowsewillgain.ThelargeconcentrationofmoosealongthelowerWoodRiverandtheTananaRiverwillbenefitfromtheregrowthofbrushintoclearedareas.Dallsheepandcaribouinthemountainousareaswillsuffersomelossofforagetotheroadbedandtowerbases.Excessivefirewilladverselyaffecttheforagefortheselasttwogameanimalssincetheyaredependentuponclimaxvegetationwhichhasaslowregrowthrate.Moosewillbenefitfromfires,uptoapoint.Excessivefiresmaytriggererosionwhichwoulddegrade,ratherthanenhance,browseformoose.Constructionactivitymaycauseavoidanceofthecorridorbyanimals;however,thisisatemporaryimpact.Operationandmaintenance"\TillnotaffecttheanimalsIoccupationofthecorridor.IncreasedaccessaffordedbytheserviceroadmayincreasehuntingpressureonDallsheep,caribou,andmoose.The·degree·ofthisimpactisdependentuponthedesirabilityofthiscorridorforhunting,andaccessandhuntingregulationsimposedbythelandmanagingagencies.Recreation:ThiscorridordoesnottraverseanyFederalorStateparksorrecreationareas.Thecorridorwillprovideaccesstoanareapre-viouslyaccessibleonlybyairorfoot.Insomecases,accessispresentlypossiblewithall-terrainvehicles.Increasedaccesswillimpactgameanimalpopulationssomewhat.Theactualimpactwilldependuponthedesirabilityoftheareaforhunting,andaccessandhuntingregulationsimposedbythelandmanagingagencies.CulturalResources:ThisalternativeapproachesnoNationalHistoricorArcheologicalsites.Ifthefinalsurveydisclosesanunsuspected archeologicalsitealongtheright-of-way,thelocationofthelineortowerswillbealteredtoavoiddamagetosuchsites.Inadvertentdamagetoanarcheologicalsitewillreduceitshistoricalvalue.Atthesametime,discoveryofanarcheologicalsiteduringsurveyorconstructionwillbeabeneficialaspect.ScenicResources:Thisalternativetraversesareasoflowtohighscenicquality.Intermsofviewercontacts,thiscorridorwillhavelittleimpactsinceitwillnotbevisiblefromtransportationroutesformostofitslength.Disregardingviewers,highvisualimpacttoscenicandwilder-nessqualityinthemountainousportionofthecorridorcanbee:h.-pected.LandUseandResources:Therewillbenoimpactsonforestryandagriculturethroughoutthisalternative.Therewillbenoimpactsonmineralorfossilfuelresources.ImpactsofAlternativeMatanuska-lSoils:FromDevilCanyontoVeeDamsite,someproblemsrelatedtopoorlydrainedwoilswillbeencountered.Generally,erosionpotentialalongthissegmentwillbelowtomoderate.Permafrostdegradationpotentialislow.Therelativelylevelnatureoftheterrainwillfacilitateconstruc-tionofanaccessroadwithoutundueerosionalproblems.Severalclear-waterstreamswillneedcrossing.Sedimentationmayoccurfromthesecrossings,butsincetheywillbecrossedclosetotheirconfluenceswiththesilt-ladenSusitna,thisimpactwillbelow.FromVeeDamsitetoSlideMountainthepotentialforpermafrostdegrada-tionisveryhigh.Thepoorlydrainedfine-grainsoilsencounteredareveryvulnerabletofrostheaving,whichwillentailmuchmaintenanceofthelineandroad.Thepotentialforscarringandruttingofthesurfaceishigh,andthesubsequenterosionmaycausesignificantsedimentationinthemanyclearwaterstreamsinthisarea.FromSlideMountaintoPalmer,thecorridorencounterslesssensitivesoils.OnceoverTahnetaPasspermafrostbecomesincreasinglydiscon-tinuous,andwelldrainedsoilspredominate.Erosionpotentialislowtomoderateandconstructionofanaccessroadshouldpresentnoundueerosionalimpacts.SteepslopesintheupperMatanuskaValleymaypresentsomeerosionalproblems,buttheslopesaregenerallystable.Thinsoilsarealsocommon,andpotentialfordenudationofslopesbelowanaccessroadcutexists,butshouldbeeasilypreventable.AppendixII-63 AppendixII64InthelowerMatanuskaValleysoilssusceptibletowatererosionareencountered,andlocationoftowersandroadwillhavetobeplannednotonlytopreventbankcutting,butalsotoavoidathreattotheinteg-rityoftheline.SincethisareaisalsotheState'sonlymajoragricul-turalarea,extensivecareshouldbetakentoavoidadverselyaffectinggoodquality,arablesoils.FromPalmertoPointMacKenzielargeareasofpoorlydrainedsoilswillagainnecessitategreatcareinlocationofthetransmissionline.Althoughpermafrostisabsent,scarringofthesoftpeatsoilsisstillapossibility,andthesubsequentsedimentationofclearwaterstreamswillhaveanadverseimpactonaquaticlife.Theheavierclearingnecessaryinthisareawillalsocontributesomewhattosedimentation;towhatdegreeisdependentuponthecareexercisedinminimizingdisruptionofthesoil.Vegetation:Ifa345kvtransmissionsystemisconstructed,thisalter-nativecouldrequireupto2,817acresofclearing,510acresmorethanSusitna-l.Ifa230kvsystemisused,upto2,514acresofclear-ingwillbenecessary,454acresmorethanasimilarsystemalongSusitna-l.ThemajorityofthisclearingwillbeinthelowerMatanuskaValleyandalongthenorthshoreofCookInlettoPointMacKenzie.VerylittleclearingwillberequiredalongtheportionfromVeeDamsitetotheLittleNelchinaRiver.Actualacresofclearingwillprobablybelessthantheabovefiguressincetheentirewidthoftheright-of-wayneednotbeclea.red.Theterrainisgenerallylevel;sotheaccessroadcanbeincorporatedintothelineclearingwithoutadditionalclearing.Theimmediateeffectofthisclearingwillbethedestructionofthevege-tation.Themuchmoresignificantimpactwillbeuponerosionandwildlifehabitats.Inhillyterrain,mechanicalclearingmethodssuchasbulldozingwillcauseconsiderabledisruptionofthesoilandsubsequenterosionandstreamsedimentation.Theuseofbrushbladesorrotarycutterswillreducethiseffect.Onsteepslopeshandclearingwillmitigatetheotherwiseheavyerosionpotentiallikelywithmechanicalclearing.Toreduceavailablefuelforforestfires,andtoreducepotentialinfes-tationofhealthybottomlandspruce-poplarbysprucebeetles(Dendroctonusrufipennis)andipsbeetles,slashmustbedisposedof.Thiscanbeeitherbysaleofmerchantabletimber,chipping,orbyburning.Althoughburningwillreduceairqualitytemporarily,itismoreeconomicalandlessdamagingthanthealternatives;so,non-merchantabletimberwillbeburnedifanaccessroadispresent.Withnoaccessroad,machinerycannotbebroughtinforstacking,burning,orchipping,anddownedtimberwillbeleftalongtheclearing.Beetleinfestationwillbeofconcernmainlyonthebottomlandspruce-poplarecosystem. Regrowthratesalongthiscorridorarefastenough,particularlyinthesouthernportion,towarrantperiodicsuppressionoftallgrowingtreeswhichposeahazardtothetransmissionline.Thepreferredmethodalongthiscorridorismanualapplicationofasuitableherbicide.Theamountofclearingtobemaintained,themodestregrowthrates,andhighcostoflabormakethisalternativepreferrableinthiscorridoroveraerialapplicationofherbicidesontheonehand,orhandcuttingofindividualtreesontheother.Ifproperapplicationtechniquesareadheredto(seeMitigatingMeasures),therewillbenootherimpactsotherthanthemaintenanceofasub-climaxvegetation.Accidentaloversprayingorwinddrift,orimproperdilution,resultinginunnecessarydestructionofvegetationandsprayingofwaterbodiesresultinginhabitatdestruc-tionforaquaticlifewillnotoccur.Sectionsneedingvegetationsuppressionoccurinthebottomlandspruce-poplar,lowlandspruce-hardwood,anduplandspruce-hardwoodforests,particularlyinthebottomlandspruce-poplar.Ivfuskeg-bogareas,whichcompriseasignificantproportionoftheecosystemscrossedbythiscor-ridorwillneedlittleclearingandnovegetationsuppression.Lowlandspruce-hardwoodareaswillnotneedtobemaintainedasoftenasbottom-landspruce-poplar.InthemoisttundraecosystemsencounteredbetweenVeeDamsiteandtheLittleNelchinaRiver,destructionofvegetationwillbelimitedtothoseareasdirectlyoccupiedbytheroadbedandthetowerbases.Thiswillbeapermanentimpact,althoughsomerevegetationoftowerbasescanbeexpected.Destructionofthevegetativematinthetundraareaswillresultinlonglastingscarsunlesscorrectiveandpreventivemeasuresaretaken.Thisscarringcouldleadtosubsequentdegradationofice-richpermafrostanderosion.Firesresultingfromconstructionandoperation,unlesssuppressedquickly,willresultinextensivedestructionofvegetation.Theseecosystemsareadaptedtonaturalwildfires,andunlesstheoccurrenceofman-causedfiresisveryhigh,theyshouldrecuperateasquicklyastheywouldundernormalcircumstances.Wildlife:Alterationofvegetationpatternswillaffectwildlife.Thiscorridortraversesmanyareasofmooseconcentration,andmooseshouldbenefitfromtheintroductionofbrushresultingfromtheregrowthontheclearing.Sincetheclearingmustbemaintained,thisbrushareawilllastforthelifeoftheline.Mostbrushareasareintransition,changingfromthebrushphasetosomeotherphasenearertheclimacticphase.Thebrushinatransmissionclearingcanbecountedasamorepermanentsourceofbrowse.AppendixI1-65 AppendixI1-66Animalsdependentuponclimacticforestsuchassquirrelswillsufferlossanddisplacement.However,theirfasterreproductiverateswillallowtheirpopulationstoadaptrapidly.Mostanimalswillbenefitfromtheedgeenvironment,offeringbothforageandcoverfromtheadjacentforestandbrush.Initially,animalmovementsmayoccuralongtheright-of-way,butasthebrushgrowsintoadensecover,thiswillbelimited.Inanyevent,thisimpactshouldbelowinthiscorridor.Constructionitselfwillaffectwildlife.Largermammalsmaytemporarilyleavetheareatoreturnaftertheconstructionactivity.Smalleranimalswillsufferlossofindividuals,butshouldrecuperaterapidlyonceconstructioniscompleted.Thedensityofforestinthiscorridorwillallowanimalstomoveonlyashortdistancetoavoidcontactwithconstruc-tionactivities.Vegetationsuppression,bywhatevermethod,willperiodicallyremovecoverfromalongtheright-of-way.However,duetothesurroundingcoveroftheunclearedforests.thisimpactwillbeinsignificant.Areasrequiringclearingcoincidewithmoosepopulations.Theresultingbrushwillbetotheirbenefit.CaribouontheuplandbetweentheSusitnaandLittleNelchinaRiverswillsuffersomedirectlossofforagefromthevegetationcoveredbytheroadbedandtowerbases.Ofmoreimport-ancetocaribouhabitatisthepotentialoverburningofkeywinterbrowse,andthesubsequentreductionofwinterrange.SincetheNelchinacaribouherdhasundergonedrasticreductionsinpopulation(fromanestimated61,000inthelate1960lstoanestimated4,000to5,000presently)anyadverseimpactoncaribouhabitatcanbeconsideredserious.Theaccessroadwillseriouslyaffecthuntingsuccessunlesshuntingisfurtherrestrictedinthisarea.TherewillbeonlyslightimpactonDallsheeprangeinTahnetaPass.Recreation:ThiscorridorapproachesnoStateorFederalparkorrecreationarea.However,areaswithahighrecreationaluseareencroachedupon.TheLakeLouiseareaisacomplexofinterconnectedlakessetuponagentle,rollinguplands,andreceiveshighuseforvacationing,fishing,andcamping.LakeLouiseitselfliesapproximately10mileseastofthisalternativecorridor.Increasedaccessandvisibilityoftransmissionstructureswillhaveimpactsupontherecreationaluse.SincetheareaisservedbyonlyoneroadtotheGlennHighway,anaccessroadwouldincreaseaccesstothearea.Thismaybeperceivedasanadverseimpactbypeoplealreadyowningorleasingsitesalongthelakeswhovaluetherelativesolitude,andmaybeperceivedasbeneficialbyfishermen,hunters,andotherswantingaccesstocabinsitesontheselakes. FromDevilCanyontoSlideMountainthiscorridorwilltraverseareaspreviouslyaccessibleonlybyfootorair.Theimpactofanaccessroadhasbeendiscussedabove.ForaccesstothenorthofLakeLouise,increasedaccesswillallowgreateruseofthisuplandarea.Forhuntersparticularly,theincreasedaccessmaybeperceivedasdesirable.Accesswillbecontrolledbythelandmanagingagencyhavingjurisdic-tionovertheseareas.CulturalResources:ThiscorridorwillapproachthesitesoftheIndependenceMinesandKnikVillage,bothNationalHistoricalSites.ThecorridorwillavoidtheIndependenceMinesbyatleast8miles;sonoimpactonthissiteisanticipated.TheKniksitewillbeapproachedupto3to5miles;however,impactonthissitewillbelowtonone.Ifthefinalsurveydisclosesanunsuspectedarcheologicalsitealongtheright-of-way,thelocationofthelineortowerwillbealteredtoavoiddamagetosuchsites.Inadvertentdamagetoanarcheologicalsitewillreduceitshistoricalvalue.Atthesametime,discoveryofanarcheo-logicalsiteduringsurveyorconstructionwillbeabeneficialaspect.ScenicResources:TherewillbeamediumtohighimpactonscenicqualityoftheTahnetaPass-upperMatanuskaValleyarea.Highexistingscenicquality,largenumbersofviewersalongtheGlennHighway,andsomedifficultyinconcealmentofatransmissionlinecontributetothisimpact.DevelopmentofthelowerMatanuskaValley,whichhasalreadyaffectedtheintactnessofthatarea,willlessenvisualimpact.Theoppor-tunitiesforconcealmentaregreateralsointhelowervalley.LownumbersofviewercontactsandeaseofconcealmentwillgreatlymitigatevisualimpactfromPalmertoPointMacKenzie.Visualimpacthereislowtomedium.VisualimpactfromVeeDamsitetoSlideMountainislow.Thisisafactoroflowviewercontacts,lowtomediumexistingscenicquality,andtowardSlideMountainsomemeasureofconcealment.LandUseandResources:AlowimpactisexpectedonagricultureontheMatanuska.Thefinalroutecanavoidpresentlydevelopedlandandhighqualityundevelopedland.Eveniflandinproductionweretobecrossed,onlythelanddirectlyoccupiedbythetowerbaseswouldberenderedunfarmable.Muchoftheagriculturallandisdevotedtodairy-ingandhay.Therewouldbeaverylowimpactontheseuses.Truckfarmingwouldbeimpactedmorethandairyingorhaysincethepatternsofrowcropswouldbeaffectedbytowerlocations.AppendixI1-67 Appendix11-68Nosignificantimpactsareexpectedonpotentialforestryalongthisalternative,norareanysignificantimpactsexpectedonmineralsextraction.Social:Somesocio-economicimpactscanbeexpectedforPalmer,Wasilla,andtheseveralsmallcommunitiesalongthenorthshoreofCookInlet.Skilledlaborwillmostlikelynotbedrawnfromthesecommunities,althoughitispossiblethatunskilledlaborfromthesecommunitiesmightbeemployedontheconstructionphase.Localservicessuchasfoodandlodgingshouldexperienceanincreaseinbusiness,butthiswillbeatemporaryimpact,andduetotherelativelysmallamountofworkersneededandtheshiftingaspectoftheconstruction,aninsignificantimpact,also.Easementswillneedtobepurchasedoverprivatelyownedlands.Thiswillgivealumpsumpayment,whichwillbeapositiveimpactuponthelandowner.Futureriseinlandpricesandassessedtaxesduetoencroachingresidentialdevelopmentwilladverselyimpactlandownerswhohaveeasementsontheirland.Theywillpaytaxonlandtheycannotdevelop,atratesfarbeyondtheratesforundevelopedland.Tncaseswherethismayoccur,somearrangementsuchasanincreasedlumpsumpaymentorannualpaymentsequaltothedifferenceintaxratesshouldbemade.ImpactsofAlternativeMatanuska-ZSoils:ImpactsonsoilsfromSlideMountaintoPointMacKenzieareidenticaltothosedescribedunderimpactsonsoilsofalternativecorridorMatanuska-l.ThroughouttheentiresegmentfromWatanaDamsitetoSlideMountainbywayofGlennallen,thepotentialforpermafrostdegradationisveryhigh.Thepoorlydrainedfine-grainsoilsencounteredareveryvulnerabletofrostheaving,whichwillentailmuchmaintenanceofthelineandroad.Thepotentialforscarringandruttingofthesurfaceishigh,andthesubsequenterosionmaycausesignificantsedimentationinthemanyclearwaterstreamsinthisarea.ParticularlysensitiveistheGulkanaanditstributaries.Thecorridorparallelsthissystemforapproximately50miles,andmultiplecrossingswillhavecumulativeeffectonsedimentation. Vegetation:TheMatanuska-2alternativecouldrequireupto3,869acresofclearingifa345kvsystemisconstructed.Thisis1,561acresmorethantheproposedSusitna-1corridor.Ifa230kvsystemisused,upto3,454acreswillneedclearing,1,394acresmorethanSusitna-l.Actualacreageofclearingwillprobablybelessthanthesefiguressincenotalloftheright-of-wayneedbecleared,andtheterrainislevelenoughsothattheaccessroadcanbeincorporatedintothelineclearing.Theimmediateeffectofthisclearingwillbethedestructionofthevege-tation.Themuchmoresignificantimpactwillbeuponerosionandwildlifehabitats.Inhillyterrain,mechanicalclearingmethodssuchasbulldozingwillcauseconsiderabledisruptionofthesoilandsubsequenterosionandstreamsedimentation.Theuseofbrushbladesorrotarycutterswillreducethiseffect.Onsteepslopes,handclearingwillmitigatetheotherwiseheavyerosionpotentiallikelywithmechanicalclearing.Toreduceavailablefuelforforestfires,andtoreducepotentialinfesta-tionofhealthybottomlandspruce-poplarbysprucebeetles(Dendroctonusrufipennis)andipsbeetles,slashmustbedisposedof.Thiscanbeeitherbysaleofmerchantabletimber,bychipping,orbyburning.Althoughburningwillreduceairqualitytemporarily,itismoreeconomicalandlessdamagingthanthealternatives,sonon-merchantabletimberwillbeburnedifanaccessroadispresent.Withnoaccessroad,machinerycannotbebroughtinforstacking,burning,orchipping,anddownedtimberwillbeleftalongtheclearing.Beetleinfestationwillbeofconcernmainlyonthebottomlandspruce-poplarecosystem.(SeeMitigatingMeasures.)InthemoisttundraecosystemcrossedfromWatanaDamsitetowithin10or20milesofPaxson,destructionofvegetationwillbelimitedtothoseareasdirectlyoccupiedbytheroadbedandthetowerbases.Thiswillbeapermanentimpact,althoughsomerevegetationoftowerbasescanbeexpected.Destructionofthevegetativematintundraareaswillresultinlonglastingscarsunlesscorrectiveandpreventivemeasuresaretaken.Thisscarringcouldleadtosubsequentdegradationofice-richperma-frostanderosion.Firesresultingfromconstructionandoperation,unlesssuppressedquickly,willresultinextensivedestructionofvegetation.Theseecosystemsareadaptedtonaturalwildfires,andunlesstheoccur-renceofman-causedfiresisveryhigh,theyshouldrecuperateasquicklyastheywouldundernormalcircumstances.AppendixI1-69 AppendixI1-70Wildlife:Alterationofvegetationpatternswillaffectwildlife.Thiscorridortraversesmanyareasofmooseconcentration,andmooseshouldbenefitfromtheintroductionofbrushresultingfromtheregrowthontheclearing.Sincetheclearingmustbemaintained,thisbrushareawilllastforthelifeoftheline.Mostbrushareasareintransition,changingfromthebrushphasetosomeotherphasenearertheclimac-ticphase.Thebrushinatransmissionclearingcanbecountedasamorepermanentsourceofbrowse.Areasrequiringclearingcoincidewithmoosepopulations.Theresultingbrushwillbetotheirbenefit.CaribouontheuplandsbetweentheSusitnaandLittleNelchinaRiverswillsuffersomedirectlossofforagefromthevegetationcoveredbytheroadbedandtowerbases.Ofmoreimportancetocaribouhabitatisthepotentialoverburningofkeywinterbrowse,andthesubsequentreductioninwinterrange.DuetothedrasticreductioninthepopulationoftheNelchinaherd,(fromanestimated61,000inthelate1960'stoanestimated4,000to5,000in1974)anyadverseimpactoncaribouisaseriousimpact.Increasedaccesswinbeaseriousadverseimpactunlesshuntingisfurtherrestrictedinthisarea.AnimalsdependentuponclimacticforestsuchassquirrelswillsufferlossanddisplacementHowever,theirfastreproductionrateswillallowtheirpopulationstoadaptrapidly.Mostanimalswillbenefitfromtheedgeenvironment,offeringbothforageandcoverfromtheadjacentforestandbrush.Initially,animalmove-mentsmayoccuralongtheright-of-way,butasthebrushgrowsintoadensecover,thiswillbelimited.Inanyevent,thisimpactshouldbelowinthiscorridor.Constructionitselfwillaffectwildlife.Largermammalsmaytemporarilyleavetheareatoreturnaftertheconstructionactivity.Smalleranimalswillsufferlossofindividuals,butshouldrecuperaterapidlyoncecon-structioniscompleted.Recreation:ThiscorridorapproachesnoStateorFederalparkorrecrea-tionarea.However,areaswithahighrecreationaluseareencroachedupon.TheLakeLouiseareaisacomplexofinterconnectedlakessetuponagentle,rollinguplands,andreceiveshighuseforvacationing,fishing,andcamping.LakeLouiseliesapproximately35milestothewest.Sincethecorridorwillparallelanexistinghighway1itisunlikelythatitwillcontributegreatlytoincreasedaccesstothislakecomplex. ExceptfortheportionfromWatanaDamsitetoDenaliDamsite,thecorridorwillparallelexistinghighway.Threfore,itisnotexpectedthatthecorridorwillprovideaccesstosignificantlylargeareas.CulturalResources:ApartfromIndependenceMinesandtheKniksitediscussedunderalternativeMatanuska-l,theonlyNationalArcheol-ogicalsiteistheTangleLakesArcheologicalDistrictwestofPaxson.Carefulexaminationofthefinalroutewillminimizeanychanceofdisruptionofarcheologicalsiteswithinthisdistrict.ANationalHistoricalSite,SourdoughLodge,willnotbeapproachedenoughtobeaffected.Ifthefinalsurveydisclosesanunsuspectedarcheologicalsitealongtheright-of-way,thelocationofthelineortowerswillbealteredtoavoiddamagetosuchsites.Inadvertentdamagetoanarcheologicalsitewillreduceitshistoricalvalue.Atthesametime,discoveryofanarcheologicalsiteduringsurveyorconstructionwillbeabeneficialaspect.ScenicResources:ImpacttoscenicqualityfromDenaliDamsitetoPaxsonwillbehigh.Largenumbersofviewercontacts,littleopportunityforconcealment,andareasofhighexistingscenicqualityarefactorsinthishighimpact.FromWatanatoDenaliDamsites,visualimpactislow.FromPaxsontoSlideMountainvisualimpactwillrangefromlowtomoderate.Fortherestofthisalternative,visualimpactsareasdescribedforalternativeMatanuska-l,LandUseandResources:Littleornoimpactisexpectedonagriculture,forestry,ormineralextraction.Thiscorridorwillparalleltheright-of-wayoftheAlyeskaPipelineandtheRichardsonHighway.Itwill,bydoingso,reinforcetheexistenceofautilitycorridorandsubsequently,thelocationoffuturerights-of-way.Somesavingsoftotalwidthofthiscorridorcouldbeachievedbysharingofrights-of-way.(SeeAlternativestotheProposedAction.)Social:Socio-economicimpactswillbeidenticaltothosediscussedforalternativeMatanuska-l,withtheexceptionoftwoadditionalcommuni-ties,GlennallenandPaxson.Sincethecorridorwillrunsoclosetoboth,itisverylikelythattheywillreceiveimpactsupontheirservicessuchaslodgingandfood.Thisisatemporaryimpact,andnotverysignificant.Somelocallabormaybeemployedduringconstruction,butthiswillprobablybeunlikely.AppendixI1-71 AppendixI1-72Easementswillneedtobepurchasedwhereprivatelandmustunavoid-ablybecrossed.Thiswillresultinthelandownerreceivingalumpsumpayment,andwillprovidesomeinfluxofcapitaltotheseareas.ImpactsoftheDeltaAlternativeSoil:Thisalternativecrossessignificantlylargeareasofsoilshavingmoderatetohigherosionpotential.Therearetwosensitivesoilareas:1)Thepoorlydrained,ice-richpermafrostfoundthroughouttheentirelengthoftheroute.Thissoilisvulnerabletopermafrostdegradation,frostheaving,andruttingandscarringofthetopsoil.2)Thesecondsensitivesoiltypeisthefine-grainsoils,generallywelldraineduplandsoils,foundbetweenShawCreekandFairbanks.Thissoilisvulner-abletogulleying,unstableslopes,andwinderosion.ErosionfromeitherofthesetwosoiltypesmaycausesedimentationinthemanyclearwaterstreamsthataretributariestotheTananaRiver.Gen-erally,theseclearwatertributariesarelimitedtothosedrainingthenortheastportionoftheTananaRivervalleyinthisarea.TributariesoftheTananafromtheAlaskaRangearesedimentladenandwillnotbesignificantlyimpactedfromerosion.Localproblemareaswillbeencountered.NorthofSummitLake,inIsabelPass,isanareaofthixotropicsoilswhichbecomeplasticunderseismicshock.Unlessthissoilcanbefeasiblycircumvented,trans-missiontowersinthisareawillbeunderhigherthannormalseismicrisk.ThroughtheIsabelPass,rockysoilsinterspersedwithbedrockandtaluswillpresentproblemsinplacingoftowerfoundationsandaccessroad.Excessivecuttingandfillingforanaccessroadthroughthisarea,inconjunctionwiththinsoilsorunstableslopes,cancausesevereerosion.Alarge,extremelymarshyareaaroundtheShawCreekconfluencewillbeencountered.Towerfoundationswillneedspecialattentionandtheaccessroadwillneedspecialdesign.Frostheavingwillbesevereinthismarshysoil.Vegetation:TheDeltaalternativecouldrequireupto1,737acresofclearing,288acres'morethanNenana-I.Theactualacreageclearedwillprobablybelessthanthesefiguressincetheentirewidthoftheright-of-wayneednotbecleared.Inareaswhereclearingisrequired,theterrainislevelenoughtopermittheaccessroadtobeincorporatedintothelineclearing. Themajorityoftheclearingwillbedoneintheuplandspruce-hardwoodandbottomlandspruce-poplaralongthelowerDeltaRiverandtheTananaRiver.Toreduceavailablefuelforforestfires,andtoreducepotentialinfesta-tionofhealthybottomlandspruce-poplarbysprucebeetles(Dendroctonusrufipennis)andipsbeetles,slashmustbedisposedof.Thiscanbeeitherbysaleofmerchantabletimber,bychipping,orbyburning.Althoughburningwillreduceairqualitytemporarily,itismoreeconomicalandlessdamagingthanthealternatives,sonon-merchantabletimberwillbeburnedifanaccessroadispresent.Withnoaccessroad,machinerycannotbebroughtinforstacking,burning,orchipping,anddownedtimberwillbeleftalongtheclearing.Beetleinfestationwillbeofconcernmainlyinthebottomlandspruce-poplarecosystem.(SeeMitigatingMeasures.)Theimmediateeffectofthisclearingwillbethedestructionofthevege-tation.Themuchmoresignificantimpactwillbeuponerosionandwildlifehabitats.Inhillyterrain,mechanicalclearingmethodssuchasbulldozingwillcauseconsiderabledisruptionofthesoilandsubsequenterosionandstreamsedimentation.Theuseofbrushbladesorrotarycutterswillreducethiseffect.Onsteepslopes,handclearingwillmitigatetheotherwiseheavyerosionpotentiallikelywithmechanicalclearing.InthealpineandmoisttundraecosystemsfoundfromWatanaDamsitethroughIsabelPassandtheAlaskaRange,destructionofvegetationwillbelimitedtothoseareasdirectlyoccupiedbytheroadbedandthetowerbases.Thiswillbeapermanentimpact,althoughsomerevege-tationoftowerbasescanbeexpected.Destructionofthevegetativematintundraareaswillresultinlonglastingscarsunlesscorrectiveandpreventivemeasuresaretaken.Thisscarringcouldleadtosubsequentdegradationofice-richperma-frostanderosion.Firesresultingfromconstructionandoperation,unlesssuppressedquickly,willresultinextensivedestructionofvegetation.Theseeco-systemsareadaptedtonaturalwildfires,andunlesstheoccurrenceofman-causedfiresisveryhigh,theyshouldrecuperateasquicklyastheywouldundernormalcircumstances.Wildlife:Theareasrequiringthemostclearingcoincidewithmanyareasofmooseconcentration,andmooseshouldbenefitfromtheintroductionofbrushresultingfromtheregrowthontheclearing.Sincetheclearingmustbemaintained,thisbrushareawilllastforthelifeoftheline.Mostbrushareasareintransition,changingfromthebrushphasetosomeotherphasenearertheclimacticphase.Thebrushinatransmissionclearingcanbecountedasamorepermanentsourceofbrowse.AppendixI1-73 AppendixI1-74ThelargenumbersofcaribouintheNelchinaherdsouthoftheAlaskaRangewillsuffersomedirectlossofforagefromthevegetationcoveredbytheroadbedandtowerbases.Ofmoreimportancetocaribouhabitatisthepotentialoverburningofkeywinterbrowse,andthesubsequentreductioninwinterrange.DuetothedrasticreductioninthepopulationoftheNelchinaherd,(fromanestimated61,000inthe1960ISto4,000to5,000in1974)anyadverseimpactisaseriousimpact.Increasedaccesswillseriouslyaffecttheherdunlesshuntingisfurtherrestricted.TherewillbeonlyslightimpactonDallsheeprangeinIsabelPassandthecanyonoftheDeltaRiver.Animalsdependentuponclimacticforestsuchassquirrelswillsufferlossanddisplacement.However,theirfasterreproductiverateswillallowtheirpopulationtoadaptrapidly.Mostanimalswillbenefitfromtheedgeenvironment,offeringbothforageandcoverfromtheadjacentforestandbrush.Initially,animalmovementsmayoccuralongtheright-of-way,butasthebrushgrowsintoadensecoverthiswillbelimited.Inanyevent,thisimpactshouldbelowonthiscorridor.Constructionitselfwillaffectwildlife.Largermammalsmaytemporarilyleavetheareatoreturnaftertheconstructionactivity.Smalleranimalswillsufferlossofindividuals,butshouldrecuperaterapidlyonceconstructioniscompleted.Thedensityofforestinthiscorridorwillallowanimalstomoveonlyashortdistancetoavoidcontactwithconstruc-tionactivities.Vegetationsuppression,bywhatevermethod,willperiodicallyremovecoverfromalongtheright-of-way...However,duetothesurroundingc()veroftheunclearedforests,thisimpactwillbeinsignificant.Recreation:ThiscorridordoesnotinfringeuponanyFederalorStateparkorrecreationarea.SincetheDeltaalternativeparallelsexistinghighwaysandtheAlyeskaPipeline,itwillnotprovidenewaccesstoanysignificantlylargearea.Useoftheiaccessroadisdependentuponregulationsimposedbythelandownersorlandmanagingagency.CulturalResources:ForthesegmentfromWatanaDamsitetoPaxsontheimpactsareasdescribedunderimpactsofalternativeMatanuska-2.FromPaxsontoFairbankstherearenoNationalArcheologicalorHistori-calSites.Ifthefinalsurveydisclosesanunsuspectedarcheologicalsitealongtheright-of-way,thelocation.ofthelineortowerswillbealteredtoavoiddamagetosuchsites.Inadvertentdamageto.anarcheo-logicalsitewillreduceitshistoricalvalue.Atthesametime,discoveryofanarcheologicalsiteduringsurveyorconstructionwillbeabeneficialaspect.78 ScenicResources:ThiscorridorwillhavevisualimpactsrangingfromhighalongtheDenaliHighwayandthroughtheIsabelPass-AlaskaRangearea,moderatefromDonnellyDometotheSalchaRiver,andtolowfromtheSalchaRivertoFairbanks.SincenearlytheentirecorridorisexposedtoviewersfromtheDenaliandRichardsonHighways,thevari-ablesaretheexistingscenicqualityandtheopportunitiesforconceal-ment.Alongthisalternative,generallythehighertheexistingscenicquality,thelesstheopportunityforconcealment.LandUseandResources:Noimpactsareexpectedonmineralsextrac-tion.TheareaaroundBigDeltaandDeltaJunctionisapotentiallymajoragriculturalarea,particularlyingraincropssuchasbarley.Crossingofgoodqualityarablelandwillresultintheremovalfromproductionofthelandoccupiedbythetowerbases.Rowcropswillbemoreaffectedthanfieldcropsinthatpatternsoftillingandharvestingwillbemoredisruptedbytowerlocations.AlongthelowerDeltaRiverandtheTananaRiverthereispotentialforforestry,particularlyinthebottomlandspruce-poplarecosystems.TheDeltaalternativewillhavelittleeffectonforestry,apartfromminimaluseasloggingroadsorfirebreaks.Merchantabletimberfromclearingoperationscanbedisposedofbysale.Theproximityofahighwayandriverwillfacilitatesalvageoflogs.ParallelingoftheAlyeskaPipelineandtheRichardsonHighwaywillreinforcetheutilitycorridoralongtheDeltaandTananaRivers,andwillaffectlocationoffuturerights-of-way.thetotalwidthofthisutilitycorridorcanbereducedbysharingofrights-of-way.(SeeAlternativestotheProposedAction.)Social:ThetownsofPaxson,DeltaJunctionandBigDeltawillbenefitfromuseofservicessuchasfoodandlodgingbyconstructionworkers.Itisunlikelythatmuchofthelaborneededforconstructionwillbedrawnfromthesmallercommunities.LoggingoftimberandclearingcontractswillaffecttownsalongtheTananaRiverbyprovidingjobsandcapitalfromsalesoftimber.Thiswillbeashort-livedimpact,however.Someeasementsacrossprivatelandmayneedtobepurchased.ThemajorityofthealternativecanberoutedalongtheutilitycorridoralongtheAlyeskaPipeline.Purchasesofeasementwillprovidealumpsuminfluxofcapitaltotheaffectedlandowners.Thisinfluxistemporary,unlessarrangementsaremadeforyearlypayments.AppendixI1-75 AppendixI1-76ComparisonofImpactsofCorridorsFromtheprecedingdescriptionsofpotentialimpactsoftheyariousalternativecorridors,comparisonscanbedrawntorankthesealternativesastotheirdegreeofcumulativeimpact.Severalassumptionswillbeusedinthesecomparisons,andfromthesecomparisonstheproposedcorridorswereselected.Thefirstassumptiontobemadeisthatotherfactorsbeingequal,cumulativeimpactsareproportionaltocorridorlength.Inotherwords,a100milecorridorwillhavetwice.thecumulativeimpacta50milecorridor.crossingsimilarterrainandecosystemswouldhave.Ifvaryingconditionsexist,thisassumptionisnotnecessarilyvalid;a100mile.corridorcrossingstablesoilsmayincurlessimpactthana50milecorridoroverice-richpermafrost.Thesecondassumptionisthatjointuseandparallelingofexistingrights-of-wayispreferabletopioneeringofanewcorridorbecauseofthesecondaryimpactsassociatedwithnewcorridors.Againstthisassumptionistheassumptionthattransmissionsystemsalwayscauseanadversevisualimpactofvaryingdegree,andthattransmissionsystemsshouldbescreenedasmuchaspossiblefrommajorsurfacetrans-portationroutes.Thusatransmissionlineideallyshouldshareorparalleltran.sportationrights-of-wayandyetnotbeseenfromthem;thisisaconditionrarelyachieved.Thefourthassumptionisthatatransmissioncorridorshouldbelocatedtoanticipatefutureneeds,andsoreducepotentialproliferationoffuturetrans-missioncorridors.Practically,thiswillfavorcorridorsthatapproachpresentandpotentialcommunitiesthatmayrequireinterconnection.Thefifthassumptionisthatthecorridorshouldfulfillitsrequirementsaseconomicallyaspossiblewhilekeepingenvironmentalimpactstoaminimum.Thisisanextensionofthefirst,second,andfourthassumptions.Usingtheseassumptionsasbroadcategoriesinconjunctionwithenviron-mentalcriteria.,thetwelvecorridorscanbesummarizedandrankedinthefollowingtable: ~ H"O I (]) ---J:::l---Jp.. 1-" X H Corridor Analysis -Project Power to Anchorage/Cook Inlet Area Susitna Corridors Matanuska Corridors Analysis Factor:S - 1 S - 2 S - 3 S - 4 M - 1 M - 2 Length,miles 136 140 129 147 258 385 Max.elevation,feet 2,100 2,100 3,800 2,200 3,000 4,000 %of joint or parallel use 75 75 39 35 52 90 Cost x $1,000 92,650 94,986 93,712 96,072 153,187 224,427 Ability to accommodate future needs 1 1 3 3 4 2 Ranking 1 1 2 1 3 4 Environmental Impacts Soils 1 2 1 1 2 2 Vegetation 2 3 1 3 4 5 Wildlife 1 2 3 3 4 3 Existing developments 3 3 2 1 3 3 Scenic quality/recreation: Developed areas 3 3 2 1 3 3 Remote areas 1 2 3 4 4 3 Ranking 1 3 1 3 4 4 ~ H'"d I (]) '-I::J00p.. l-" X H Corridor Analysis -Project Power to Fairbanks/Tanana Area Nenana Corridors Delta Corridor Analysis Factor:N -1 N -2 N -3 N -4 N -5 D Length,miles 198 220 231 223 212 280 Max.elevation,feet 2,400 4,300 4,000 4,000 4,300 4,000 %of joint or parallel use 100%38%78%43%0%86% Cost x $1,000 85,382 107,090 106,272 95,648 96,572 122,475 Ability to accommodate future needs 1 4 3 4 5 2 Ranking 1 3 3 3 4 3 Environmental Impacts Soils 1 3 2 2 3 3 Vegetation 2 2 3 2 1 3 Existing developments 3 2 2 2 1 2 Scenic quality/recreation: Developed areas 3 2 2 1 1 3 Remote areas 1 3 2 2 3 2 Ranking 1 3 3 2 1 3 Combiningtheinformationonthistablewiththemoredetaileddescrip-tionsofpotentialenvironmentalimpactsofthecorridorsinpages34to74,abriefdiscussionofeachcorridoranditsrelativesuitabilityfollows:Susitna-lOfthepossiblecorridorsfromtheUpperSusitnaProjecttotheAnchoragearea,theSusitna-lcorridoristhesecondshortest,andoneoftheclosestadherentstoexistingcorridors.Becauseofthefairlyheavytomoderateforestdensity,theclearingcanbescreenedfromtheparallelAlaskaRailroadandAnchorage-FairbanksHighway.OfthesixcorridorsleadingtotheAnchoragearea,thisisthecheapesttoconstruct.Someoftheadvantagesofthiscorridorareitsdirectnessanditsproximitytosmallcommunitieswhichmayeventuallyrequireadirecttap.ItavoidstheDenaliStateParkandconsequentialscenicimpactsasseenfromthehighway,andavoidsunnecessarycrossingsoftheSusitnaRiver.Thedisadvantagesofthiscorridorare:theadditionalaccessprovidedtotheareabetweenTalkeetnaandGoldCreek,whichispresentlyservedbyfla.gstopsontheRailroad;thenewaccessprovidedtotheareabetweenNancyLakeandPointMacKenzie;andthepossibleinterferencewithrecreationintheNancyLakeRecreationArea.Susitna-2ThiscorridorisslightlylongerthanSusitna-l,moreexpensive,andwillinterferewithrecreationintheDenaliStatePark.ConcealabilityofthelinefromtransportationroutesisequaltoSusitna-l,asisitsabilitytoincorpor-atefutureelectricalneedsofcomlr.unitiesenroute.InterferencewiththeNancyLakeRecreationAreaandthenewaccessprovidedtoPointMacIZenzieissimilartoSusitna-l.Themajordisadvantageofthiscorridorwillbetheinterference\x:iththeDenaliStatePark;itwouldpracticallyrendertheParkareatotheeastoftheHighwayueslessforhikingtrails,sincetrailsofanylengthoverfivemileswouldcrosstheright-of-way.Forthisreason,itisnotpreferredoverSusitna-l.Appendix11-79 AppendixI1-80Susitna-3Thisistheshortestofthecorridors,andthesecondtothecheapestcorridortoAnchorage.Itavoidsvisibilityfromtransportationroutesbystrikingtothenortheastthroughrelativelyinaccessiblecountry.Thus,itislessabletoaccommodatenewtapsalongthestretchfromTalkeetnatoGoldCreek.TheproximitytoNancyLakeRecreationAreaandtheaccesstoPointMacKenziearesimilartoSusitna-l.Thiscorridorhas1:>'1'0seriousdisadvantages:First,itwillpioneeraconsider-ableareaofland,reducingwildernessvaluesandpermittingproblemswithincreasedaccess.Secondly,itwillbemorevulnerabletoweatherandrelia-bilitywillbereduced.Forthesetworeasons,itisnotfavoredoverSusitna-l.Susitna-4ThiscorridorisconsiderablylongerandmoreexpensivethanSusitna-l;only33%ofitslengthfollowsexistingcorridors,sinceitavoidspublictransporta-tionroutesbyleadingnortheasttoDevilCanyonfromTalkeetna.ItisnotasabletohandlenewloadsfromTalkeetnatoGoldCreekasSusitna-l;theprox-imitytotheNancyLakeFecreationAreaandtheincreasedaccesstoPointMacKenziearesimilartoSusitna-l.Thelargeareaofnewaccessprovided,withitsattendantproblems,combinedwithrecreationaluseoftheStephanLakeareareducethevalueofthiscorridor.Becauseofthisanditshighercost,itisnotpreferredoverSusitna-l.Matanuska-lThiscorridorisalmosttwiceaslongasSusitna-l,andabout60%moreexpensive.Halfofitslengthparallelsexistingcorridors;whereitdoesfollowthesecorridors,itsconcealabilityvariesfromlowtohigh.Itispoorlysuitedtoaccommodatefutureelectricalneeds.Thereareseveralmajorenvironmentalobjectionstothiscorridor.First,itwouldopenupaverylargeareaofpreviouslyinaccessible(exceptbyair)area.Thisareaisuniqueinmanyways:first,itisaconsiderablepartoftheNelchinacaribourange,andsincethisherdhassufferedmajordeclinesrecently,anyimpactontheirrangewillbeadverse.Secondly,thisareahasahighrecreationaluse,suchasfly-inhunting,fishing,andcabins;increasedaccessmayreducewildernessvaluesforthissortofrecreation.Thirdly,thisisalargeareaofcontinuousice-richpermafrost.Theseobjec-tions,combinedwithitslengthandcost,ruleoutthisalternative. Matanuska-2ThiscorridorisalmostthreetimeslongerthanSusitna-1andalmost150%moreincost.However,mostofitslengthparallelsexistingcorridors;v-1.sibilityfromtransportationrouteswouldbemediumtohighformuchofitslength.Itwouldbewell-suitedtotheinterconnectionoftheCVEAsystem.Sinceitfollowsexistingcorridorsformostofitslength,thenew-accessproblemisratherlowforthisalternative.Themajorenvironmentalobjectiontothiscorridorwillbethelargeareaofice-richpermafrosttobecrossed,andvisibilityinscenicareas,asinTahnetaPassandtheUpperIv1atanuskaValley.However,itslengthandcostareinordinatelyhigh,sothiscorridorisnotrecommendedatthistime.Nenana-1TheNenana-lcorridoristheshortestandcheapestcorridorconnectingtheUpperSusitnaProjecttoFairbanks.Itwouldparalleloruseexistingrights-of-wayforitsentirelength,anditsabilitytoaccommodatefutureelectricalneedsareverygood.ThemainobjectiontothiscorridorwouldbethelackofconcealmentfromsouthofBroadPasstoHealy;varyingdegreesofvisualimpactalongthisstretchcouldbeexpected.AlthoughnotenteringtheMountMcKinleyNationalPark,itwouldbevisiblealongtheAnchorage-FairbanksHighwayinthevicinityofthePark.Noothermajorenvironmentalproblemsareantici-pated.Tofurtherreduceimpact,noaccessroadisplannedfromHealysouthtotheProjectarea.Thismodificationwouldapplynotonlytothiscorridor,butalsototheCantwell-GoldCreeksectionsofNenana-2andNenana-3.Nenana-2AlthoughnotmuchlongerormoreexpensivethanNenana-I,thiscorridorwouldprovideaccesstoaverylargearea;only38%ofitslengthfollowsexistingcorridors.ThosesectionsparallelingtheAnchorage-FairbanksHighway/AlaskaRailroadcorridorwouldberathervisible.Theincreasedaccessisamajorenvironmentalobjection;themajorrecrea-tionaluseofthisaccessroadwouldbeforhunting,andwildernessqualityofthisareawouldbeirreversiblydamaged.AnothermajorobjectionisthenecessityofcrossingseveralhighpassesintheAlaskaRange;reliabilitywouldbeless,notonlybecauseofharsherconditions,butalsotouncertaintyofaccessforrepairs.ThiscorridorislesssuitablethanNenana-I.AppendixI1-81 AppendixI1-82Nenana-3Thiscorridorismoreex-pensiveandlongerthan:Nenana-l.Itparallelsexistingrights-of-wayformorethan75%ofitslength,circumventingtheNenanacanyonareabywayoftwootherpassesintheAlaskaRange.FromtheProjecttoCantwell,itwouldberathervisible.ItismuchbettersuitedtoconnectexistingandpotentialcommunitiestotheinterconnectedsystemthanNenana-2,butwillnotbeabletobetappedbyMcKinleyPark.Asignificantareaofmountainousterrainwillbeopenedupbythiscorridor,unlesshelicopterconstructionisused.Onehighpasswillneedtobecrossed;theharshconditionswillreducereliabilityofoperationandaccess.ThiscorridorisnotpreferredoverNenana-].Nenana-4SlightlylongerandmoreexpensivethanNenana-I,thiscorridorwouldnotbeseenfromtransportationroutesfromtheProjectareanorthtoHealy.Lessthanhalfofthiscorridorparallelsexistingrights-of-way,anditwouldbepoorlysuitedtoaccommodatefutureelectricalneedsofexistingorpotentialcommunities.NotonlywouldthiscorridorhavethesameobjectionsasthatofNenana-3,italsowouldprovideaccesstotheareaimmediatelynorthofWatanadamsitetotheDenaliHighway,dividingwhatisnowafairlylargewildernessarea.ThisareacanbeeA.-pectedtoprovideunsuitablesoils,muchofitice-richpermafrost.Nenana-4isnotpreferredoverNenana-I.Nenana-5Thiscorridorisuniqueinthatitswholelengthpioneersanewcorridor;noexistingrights-of-wayareparalleled.Yet,itslengthandcostarenotmuchgreaterthanNenana-l.Itwouldbeverypoorlysuitedtoaccommodatefutureelectricalneedsofexistingandpotentialcommunities.ThiscorridorcombinestheobjectionsofNenana-2andNenana-4,anditsonlyadvantagewouldbeitsconcealmentfromtransportationroutes.Thus,thiscorridorisnotrecommended. DeltaTheDeltacorridoristwiceaslongand50%moreexpensivethanNenana-I.Mostofitparallelsexistingrights-of-way,andformanystretches,wouldbehighlyvisiblefromtheDenaliandRichardsonHighways.Ithasafairsuit-abilityforaccommodatingfutureelectricalneedsofexistingorpotentialcommunities.Inaddition,itcanservetopowerpipelinepumpingstationsandconnecttheCVEAandGVEAsystems.Themajorenvironmentalobjectionstothislineare:thereisalargeareaofpoorsoilstobecrossedalongtheDenaliHighwayandthroughIsabelPass;thelinewouldalsobehighlyvisibleinthesetwoareas.Thiscorridorin-fringesontheNelchinacaribourange.SincetheNelchinaherdhassufferedsuchdramaticlossesinthepasttenyears,anyimpactontheirrangeshouldbeconsideredadverse.TheonlyEndangeredSpeciesinAlaska,thePeregrinefalcon,wouldbeaffectedinitshabitatalongtheSalchaBluffs.AlargearcheologicaldistrictwouldhavetobecrossedwestofPaxson.Theseobjec-tions,combinedwithlengthandcost,ruleagainstthisalternative.TheselectionoftheNenana-IandSusitna-Iastheproposedcorridorsdoesnotdisavowtheimpactsassociatedwiththem;itonlyselectsthesetwoasthemosteconomicallydesirableandtheleastenvironmentallyobjectionablealternatives.Lessening,ormitigation,oftheimpactsofthesetvvocorridorsisdiscussedinthefollowingsection.AppendixI1-83 AppendixI1-84MITIGATIONOFIMPACTSMostmitigatingmeasuresarebasicallystandardpracticesstringentlyenforced.IfbasicapplicableregulationsissuedbytheFederal,State,andlocalgovernmentsregardingenvironmentqualityareadheredto,mostimpactsaffectingairandwaterqualitywillbeminimized.ApplicationofpracticesandguidelinessuchasthoseissuedinEnvironmentalCriteriaforElectricTransmissionSystems,ajointDepartmentoftheInterior,DepartmentofAgriculturepublication,willreducevisualandenvironmentalimpacts.Consultationwithagenciesproficientincertainareasofconcern,suchastheSoilConservationServiceandtheStateDepartmentofFishandGame,willprovidefurtherguidanceonmitigationofimpacts.Morespecificmitigatingmeasuresarediscussedbelow.Itmustberememberedthatmanyofthesearestandardpracticesintendednotonlytominimizedamagetotheenvironment,butalsotoprotecttheintegrityofthetransmissionline.ExperiencegainedfromconstructionandmaintenanceofothertransmissionsystemsinAlaskahasshownthatmostenvironmentalimpactsfromtransmis-sionlinescanbeavoided.GoldenValleyElectricAssociationandChugachElectricAssociationhaveconstructedandoperatedseverallineswithoutaccessroads,onpoorsoils,andunderharshclimaticconditions.Exceptforvisualimpact,mostenvironmentalimpactscausedbyatransmis-sionsystemarefarlessthanmanytransportationandcommunicationsystems;particularlyifitisanoverheadsystem.Themajorityoftheimpactsareduetotheaccessroads;iftheaccessroaccanbeomitted,alargeportionofthepotentialimpactswillbeeliminated.Thefollowingmitigativeprocedureswillassumetheexistenceofanaccessroadanditspotentialimpacts;itmustberememberedthataccessroadswillnotbeusedwheretheyareshowntobeincompatiblewiththeenvironment.SoilsSinceitisexpectedthatmostdamagetosoilswilloccurduringtheconstructionphase,theconstructionschedulecanbearrangedsothatconsiderableamountsofthework,particularlythoserequiringtheuseofanaccessroad,suchasdeliveryofmaterials,canbedoneinwinterandspring,whenthegroundisleastvulnerabletophysicaldisturbances. However,winterroadusewillbedependentuponsnowdepthandsurfaceconditions;winterusecanaffectsurfacevegetationthroughdestructionofsurfaceplants,orover-compactionofsnow.Temporaryroadswillbeavoidedasmuchaspossible;accessroadswillbebuilttoastandardapplicabletotheexpecteduse.IfsodesignatedbytheStateDepartmentofHighways,somesectionsofa.ccessroadswillbebuilttosecondaryroadstandards.Notallsectionsofthelinewillrequireanaccessroad;particularlysensitiveareasmaybeprotectedbytheuseofhelicopterconstructionandmaintenance,ortheuseofwinteraccessroadsandhelicoptermainten-ance.Itshouldberecognized,however,thatdependenceonaerialmethodsleavestheconstructionand/ormaintenanceprogrammorevulnerabletoweatherconditions.OnemajorsectionwillbeconstructedwithoutaccessroadsfromDevilCanyontoHealy.Forgroundwork,roadsmustbeadequatelyconstructedtoavoiderosion,slopeinstability,degradationofthepermafrost,andalterationofdrainage.Gravelorotherinsulatingmaterialshouldunderlaypermanentaccessroadsonpermafrostarea;culvertsandbridgeswherenecessaryshouldbeplacedtoavoiddisruptionofdrainageandpossibleicingconditions.Slopesoncutsandfillsshouldbeofpropergradientandrevegetatedassoonaspossibletopreventerosionandslumping.RevegetationwillbedonewithspeciesrecommendedinAVegetativeGuideforAlaskapublishedbytheSoilConservationService.Forgroundworkoffoftheaccessroad,orwherenoaccessroadwillbeprovided,machinerycompatibletothesurfaceshouldbeused.Forshallowpermafrostareas,softmuskegandbogs,andhighlyerosivesoils,machinerywithlow-pressuretreadsortiresshallbeusedtoavoidscarringthevegetativematandincurringsubsequenterosion.Onsensitivesoils,suchasice-richsoilswithashallowpermafrosttable,disturbedsoilwillbeprotectedwithanorganicinsulatingmulch,suchasstraw,orwhenavailable,chippedslashfromtheclear-ing.Revegetationwithappropriatecoverplantswillimmediatelyfollowconstruction.Toreducethelikelihoodofdisturbanceofmarshysoils,matsofslash,logs,orothermaterialswillbeused.Onerodableslopes,nobulldozingwillbedoneonslopesgreaterthan35%.Allcutsandfillsshallbeangledbacksufficientlytominimizeslumpingandimmediatelyseededwithappropriateplants.SoddingorfabricmatsmayneedtobeusedinsomecasestominimizeerosionuntilAppendixI1-85 AppendixI1-86revegetationcancontrolslopeerosion.Culvertsandwaterbreakswillbeplacedtoreducewaterflowoverthebareroadbed.Nomachineclearingwillbepermittedwithin100feetofanystreambed.Toprotecttheintegrityofstructuresinextremelymarshysoilsorsoilswithashallowice-rich,permafrosttable,andtominimizeuseoftheaccessroadformaintenanceoftowerfootingsonthesesoils,heattransferdevicesmaybeusedifnecessarytokeeptowerfootingsandguysfrozenintoplace.Thisisespeciallyimportantinthosestretchesnothavinganaccessroad.Keepingpoorlydrainedsoilsandtheshallowactivezonearoundtowerbasespermanentlyfrozen,eliminatesfrost-heavingofanchorsandsettlingoffoundationsduetochangesinthepermafrost.Thereareseveraltypesofthesedevicesinuse;theiruseiswidespreadalongtheAlyeskaPipelinewhereelevatedsectionsofpipearevulnerabletosettling.Agooddiscussionofseveraltypesofthesedevicesisfoundinthearticle"SettlingaProblemofSettling",intheNorthernEngineer,VoL7,no.1.Thebasicprincipleofthesedevicesisthatof"pumping"heatfromthesoiltotheair.Year-roundoperationwouldrequireanactualpumptokeepcoolantflowing,butseveraltypesusenopump,relyinginsteaduponthedifferencebetweensoilandambientairtemperaturesinwinterandone-wayflowofcoolanttoretardheattransfertothesoilinsummer.Theseheat-transferdevicesmayprovidethebestavailablesolutiontotheproblemofsuitablefootingsandanchorsforstructuresinmuskeg.Firecontrolwillbequickandefficienttolimitfirestosmallareas.Firecontrolmethodsandmachineryshouldnotultimatelycausemoredamagethanthefiresthemselves;soildisruptionbyfirecontrolmustnotaggravatesoildisturbancealreadycausedbyafire.Aerialcontrolandgroundvehicleswithlow-pressuretreadswillbeusedwhereneeded.Crewswillbeinstructedonfiresafety.Extinguishingtoolswillbeonhand;machinerywillbesuitablymaintainedtominirrdzesparking.Workwillgoonaspecialbasisduringhigh-riskperiods.Thepermanentaccessroadcandoubleasafirebreakandafire-controlroadforcontinuingwildfiremanagement.Onunbridgedstreamcrossings,gravelfordswillbeconstructedwherethebottomisnotalreadygravel.Notreesshallbefelledoryardedacrossstreams.Nowastematerialwillbedumpedintostreamsor abandonedontheirfloodplains.Towerswillbelocatedwellawayfromstreams,notonlytoreducethepotentialforerosion,butalsofortheirownsafety.VegetationOnlythenecessaryvegetationwillbeclearedtominimizeimpactandcost.Photogrammetricidentificationofclearingzoneswillbeused;thistechnique,alreadyinusebyBonnevillePowerAdministration,usesacombinationoffactors,includingspacingoftowers,linesag,topo-graphy,profiles,andgrowthratestodetermineexactlywhichtreesneedtobeeliminatedinaforestedarea.DesignationoftheminimumsafeclearingwillbeinkeepingwiththeNationalElectricSafetyCode.Clearingwillbewithbrushbladesonbulldozersonfrozenground,aswellaswithrotarycuttingorhandclearingtoreduceunnecessarydisruptionofvegetation.Nobulldozingwillbepermittedonslopesgreaterthan35%.Clearingonsteepslopeswillbebyhand;stumpsandrootswillbeallowedtoremaintohelpkeepslopesstable.Slashwillbeimmediatelychippedtoprovideerosioncontrolwherenecessaryorburnedtoavoidpotentialinsectepidemicsandtoreducefirehazard.Non-merchantabletimberwillbeburnedifanaccessroadispresent.Withnoaccessroad,machinerycannotbebroughtinforstacking,burning,orchipping,anddownedtimberwillbeleftalongtheclearing.Beetleinfestationwillbeofconcernmainlyonthebottom-landspruce-poplarecosystem.Disturbedareaswillbegradedbacktomergewiththecontoursoftheland,andfertilizedorrevegetatedifnecessarytoprovideagroundcover.Inmanycases,chippingofbrush,averysuitablemethodofreducingsoilerosionintheclearing,willalsoprovidesomeincreaseofinsulationinareasofshallowpermafrost.Firehazardwillbelow,sincethechipswillusuallybeinwetsoilsintheseconditions.Revegetationofclearedareascanbewithplantspeciesthatwillenhancehabitatforanimals,yetcansuccessfullydominatetaller-growingspecies.Typicalofthesespeciesaregrassesandlegumes.RevegetationwillbecarriedoutinaccordancewithAVegetativeGuideforAlaskapresentlyusedbytheStateDepartmentofHighways.Thosesectionsofclearingneedingperiodicmaintenancetokeepdowntall-growingtreeswillbeclearedinsuchawayastominimizefurthersoildisruption.Ifmechanicalmethodsareused,selectivecuttingispreferableoverbrushhogsorbrushbladesontractors,whichnotonlyAppendixI1-87 AppendixI1-88canbedestructivetothesoil,butinefficient,also,inthatlittleselectivecuttingispossible.Ifherbicidalcontrolistobeused,properapplicationmethodsandproperherbicidemethodswillbeused.Aerialapplicationwillnotbeused;manualapplicationisnotonlyveryselective,butaccidentalmisapplicationislesslikelytooccur.Herbicideswillnotbeappliednexttostreamsorlakes;abufferstripwillbeleftuntreatedadjacenttowaterbodies.Applicationwillbeofacoverageanddilutionappropriatetothevegetationbeingtreated.Firecontrolwillbeasdiscussedintheprecedingsectiononsoils.WildlifeApolicyofminimalclearingofvegetationshouldhavetheleastimpactuponwildlifeintermsofdestructionofhabitat.Avoidanceofuniquehabitat,orhabitatofrareandendangeredspecieswillminimizeimpactontheseimportant,butusuallylocalized,areas.Seasonalschedulingofconstructionwillminimizecontactswithmigratingmammals,althoughthismayconflictwithwinterconstructioninareasusedbywinteringcaribouormoose.Anyaccessroadswillbedesignedtominimizerivercrossings,whichshouldreducesedimentationcausedbyfordingmachinery.Wherepossible,drainagewillbepreservedthroughproperplacingofculvertsandbridges.Borrowpitswillbelocatedtoavoidsedimentationofclearwaterstreamsandlakesandsubsequentimpactsonaquaticecosystems.Spillsoffuel,oil,andotherchemicalswillbeavoided,particularlyifstreamsorlakesmaybeaffected.Herbicides,ifused,willbeappliedproperly.Wildfirecontrolwillbeasdiscussedinthesectiononsoils.Harassmentofwildlifebygroundvehicles,planes,orhelicopters,eitherdeliberateorinadvertant,willbeminimizedbystrictenforce-mentofvehicleuseandaircraftusebyeitherthecontractorsorthesupervisorsduringconstructionandmaintenance.Huntingandtrappingactivitiesofworkcrewswillbecontrolled.TheAlyeskaPipelinecampsrestrictfirearmspossessiontocontrolhuntingandharassment,aswellasaccidentalshootings.TheAlyeskaPipelinecampandconstructionareashavealsobeenclosedtohuntingandfishingbytheAlaskaStateDepart-mentofFishandGame.Similarcontrolswillbeemployedfortransmissionlinework.Increasedexposureofwildlifetohuntingortrappingbecauseoftheincreasedaccessofaserviceroadcanbecontrolledtoadegree,ifdeemednecessarybygamemanagementagencies.Accessroadheadscanbe barricadedorconcealed,breakscanbedesignedontheaccessroadtolimitusebystandardfour-wheeldrivevehicles,andtheroadcanbeposted.However,itisnotexpectedthatsuchaccess-controlmeasureswillentirelysucceed.Inmostareas,AlaskaPowerAdministrationfavorsmultiple-useoftheright-of-way;finalregulationofaccesswillbeatthediscretionofthelandownerorland-managingagency.ExistingDevelopments-SocialToavoidpreemptionofprivatelands,thefinalroutewillbeflexibleenoughtocircumventsmallblocksofprivateland.Largerprivatelyownedsectionswillentailapurchaseofeasement.Allofthealter-nativecorridorscanavoidcommunitiesenroute.SectionsofthelinedeemedhazardousbytheFAAwillbeadequatelymarkedasoutlinedinPart77,FAAregulations"ObjectsAffectingNavigableAirSpacell•Effectsofaudiblenoiseandelectromagneticinterferenceareminimizedbythedistancebetweenthemajorityofthecorridorandresidences,especiallyresidenceswithradioand/ortelev-isionreception.Avoidanceofcommunitiesforthemostpartwilleliminatethenuisancesofnoiseandinterference.Parallelingcommunicationlinesvulnerabletoreducedinterferencecanbere-routedtominimizethedistancealongwhichtransmissionandcommunicationlinescloselyparallel.Themagnitudeofinducevoltageisinverselyproportionaltothesquareoftheseparatingdistance,sodoublingthedistancebetweenthetransmissionlineandcommunicationlineswouldreduceinducedinterferencetoaquarter.Campswillbeprovidedfortransmissionlineworkers;theseandallmaterialdumpsandconstructionareaswillbelocatedawayfromsmallcommunities;suchprecautionswillnotbeneededforthelargertownsofAnchorageandFairbanks.Thecampswillbetemporary,andwillberemovedastheconstructionphaseintheirvicinityiscompleted;thelandoccupiedbythecampswilleitherreverttotheirformeruseorusedforotherpurposes.Dependingupontheabilityofthecommunitytoabsorbaninfluxofpeople,thecampswillprovideforentertainment,food,andlodging.Thiswillminimizethestrainonsuchservicesinthecommunities,atthesametime,allowinglocalmerchantstoprofitfromtheseservices.ScenicQuality-RecreationTheobtrusivenessofatransmissionlinecanbelessenedbyproperdesignandlocation.Inforestedareas,placingtheclearingfarenoughAppendixII-89 AppendixII-90fromaparallelhighwayorrailroadissufficienttoconcealthetransmissionline.Inareashavingshortertrees,usingthetopographytoconcealalinebehindridges,inswales,andalongbreaksinslopeswillhelptolessenitsvisibility.Incompletelyopenareas,theonlyalternativesareusingacombinationoftopographyanddistancetoconcealaline,ortokeepitclosetotheroadifitcannotbeconcealed.Bykeepinganobviouslinenexttoaroad,onecanwalkunderthelinetogetanunobstructedviewofsceneryontheotherside;merelykeepinganunconcealablelineashortdistancefromaparallelroaddoesnotlessenitsobtrusiveness,anditprecludesgettingaclearviewofscenerybeyond.Othertechniquesofconcealingormitigatingthepresenceofalinearetoavoidclear-cutsforclearings,butinstead,tofeatherbackthebreakbetweenoriginalforestandclearing;useofphotogrammetricselectiveclearingwilleasetheabruptappearanceofclearings.Whereroadcrossingsarenecessary,itisbesttocrossatlessthanrightanglesandtoleaveabufferstripoforiginalvegetationtomasktheright-of-way.Thismightinvolveusingtallerthanusualtowersoneithersideofthehighwaytoprovidetheadditionalclearance.Placinglinesonridgessilhouettesthem,andwillbeavoided;ridgecrossingsarebestputinnotchesorlowspots.Wheneverpossible,existingrights-of-wayshouldbesharedorparalleledtoavoidtheproblemsassociatedwithpioneeringacorridorininacces-sibleareas.TrailsintheseIlinaccessiblellareasshould,however,beavoided;preservingwildernessqualityentailssharingorparallelingallrights-of-wayexcepttrails,andfromthese,linesshouldbeshieldedasmuchaspossible.CulturalResourcesThereareknownandpotentialarchaeologicalandhistoricalsitesalongtheproposedcorridors.Tominimizepossiblevandalismordisturbance,nositesotherthanthoseontheNationalRegistershallbelocatedeitheronamaporonthenarrativeofthisassessment.Topreservetheintegrityoftheseknownandpotentialsites,apre-constructionarchaeologicalsurveyofthecorridorswillbecarriedout,andthefinaltransmissionroutewillbeadjustedtominimizedisruption.Inadvertentdiscoveryofanunsuspectedsiteatalaterstagewillentaileithertheminorrelocationofasegmentofthetransmissionline,orthesalvageofthesiteasprescribedbyExecutiveOrder11593andP.L.93-291. Forsitesalreadydisturbed,suchasthoseuncoveredduringexcavation,accuraterecordsofthesitewillbeprepared;thesitewillbestudiedtodetermineitssignificanceandtheextentofdisturbance.Allphoto-graphs,drawings,anddescriptionswillbefiledwiththeLibraryofCongressaspartoftheHistoricAmericanBuildingsSurveyortheHistoricAmericanEngineeringRecord.Ifthesiteisofsuchsignifi-cancetowarrantmoredetailedstudy,constructionworkshallbetemporarilyhaltedonthevicinityofthesite;ifnecessary,aminorrelocationcanbearrangedtopreventfurtherdisruptionofveryimportantsites.AppendixI1-91 AppendixI1-92ADVERSEENVIRONMENTALIMPACTSAllgenerationofpowerwillcreateadverseimpacts,alltransmissionofpowerwillcreateadverseimpacts;allgenerationsites,exceptforlocalgeneration,needatransmissionsystem.Thedegreeofadverseimpactofatransmissionlinewillvarywithitslength,thecharacteroftheterrain,andthecareexercisedindesign,construction,operation,andmaintenance.AdherencetoregulationsandguidelinesissuedbytheNationalEnvironmentalPolicyActof1969,theWaterQualityAct,andrelevantStateandlocalagenciesandapplicationofmitigatingmeasuresasoutlinedintheprecedingsectionwillreduceunavoidabledetrimentalimpactstoaconsiderabledegree.ExperienceinconstructionandmaintenanceofthemorerecenttransmissionlinesofAlaskanutilitieshasshownthatmostadverseimpactscanbeavoidedormitigated.TheHealy-FairbanksandtheBeluga-PointMacKenzietransmissionlineshavebeensuccessfulincrossingawidevarietyofecosystemswithlittledamage.Theselineshaveusedwinterandhelicopterconstructioninadditiontoconventionalvehicleaccessroads.Theuseoftheexperiencegainedintheseprojectswillreducethedegreeofadverseimpactsconsiderably.However,someunavoidableimpactsareinevitable.Theseimpactsareoftwokinds:Thoseresultingfromtheconstructionactivities,andthoseinherentintheexistenceofatransmissionline.Unavoidableimpactsduetoconstructionactivitiesareusuallytemporary;theseincludeeffectssuchasdisruptionofthesurfacevegetationandsubsequenterosiononslopes;disruptionofanimalhabitatduetohumanpresence;andlossofvegetationduetoclearing.Thedegreeoftheseimpactswilldependuponthemitigationmeasurestaken,timingoftheconstructionphase,andecologicalfactors;theseimpactswilllessenorceaseafterconstructtion,asregrowthofvegetationandreinvasionoffaunaoccurs.Unavoidableimpactsofamorepermanentnatureassociatedwithmaintenanceandoperationofthetransmissionlineincludemodificationofhabitatduetoamaintainedclearing;increasedaccessandsubsequentimpactsofincreasedaccess;influenceonexistingandfuturelanduse;influencesonexistingandfutureutilitycorridors;andveryimportantly,impactsonscenicquality.Themaintenanceofaclearingthroughforestedareaswillhaveimpactsonwildlifeforthelifeofthetransmissionlines.Animalsdependentuponsuccessionalvegetationforbrowse,suchasmooseandsnowshoe hare,willbenefitbytheintroductionofbrushintoanotherwiseforestedarea.Animalsdependentuponclimaxforestforhabitat,suchasredsquirrel,willsufferareductionofhabitat.Ingeneral,bothoftheseimpactswillbeinsignificantduetothesmallratioofaffectedlandtotheareaofunaffectedforesttraversedbyatransmissionroute.Increasedaccessduetotheexistenceofatransmissionlinewilldependuponthetypeofaccessusedtotheline,thedegreeofpresentaccess-ibility,theareaofinaccessiblelandopenedup,andtheattractionforactivitiesotherthanlinemaintenance.Somesectionsofthelinewillhavenoaccessroad;somewillbeservicedbytemporaryconstructionroadsorwinterroads;somesectionswillbeservicedbyanaccessroadsuitableforfour-wheeldrivevehicles.Thus,accesswillbeeffectivelydeniedtovehiclesunabletonegotiatearoadofthisstandard,andinmanyareas,toallvehiclesexceptall-terrainvehiclesoraircraft.Iftheareaisalreadysuitablyservedbyanexistingroadofhigherstandards,itwouldbeexpectedthatatransmissionlineaccessroadwillnotappreciablyaffecttheexistingaccess.Also,itwouldbeexpectedthatlargeareasopenedupbyanewaccessroadwouldreceivemoreimpactsthansmallerareas;however,itcanalsobereasonedthatlargerareascanabsorbthegreaterimpactsofincreasedaccessmoreeasilythansmallerareas.Ifotherfactorsareconsideredequal,impactsofincreasedaccesswilldependuponthearea'sattractivenessforhunting,packing,camping,andsightseeing.AlaskaPowerAdministrationpresentlyfavorsmultiple-useoftransmissionrights-of-way.Sincemostoftherights-of-waywillbeeasementsonStateandprivatelands,andlandsmanagedbyotheragencies,deter-minationofaccesswillbelefttothelandownersormanagers.Therewillbeanunavoidableimpactonpresentandfuturelanduse;thedegreeofthisimpactisafunctionoftheexistinguseandthepotentialusesofnotonlythelandoccupiedbythetransmissionline,butalsotheadjacentlands.Presently,thereislittleagricultureorforestryalongthealternativecorridors;residentialareasarelargelylimitedtotheAnchorage-PalmerandFairbanksareas.However,futurepatternsoflandusewillchange;agriculturalpatternsadjacenttoatransmissionlinewillbeaffectedsomewhat,dependingonthecropandthemethodofagriculture.Sincethetransmissionlinewillprobablypredateagriculturallandusealongthecorridor,thisAppendixI1-93 AppendixI1-94impactwillbeslight,andprobablybeneficial,sincearight-oi-waywouldprovideclearedlandatlittleornoexpensetothefarmer.Irrigationandtillingmethodswillhavetoadaptthemselvestothespacingofthetowers;landoccupiedbythetowerbaseswillbeunusable,butthislandisasmallfractionoftheright-of-way.Forestryispresentlylimitedbyphysical,economic,andownershipfactors.Presentforestryareascaneasilybecircumvented;potentialareasmaybenefitfromtheexistingaccessroadofthetransmissionlinenotonlyforlogging,butalsoforfirecontrol.Theexistenceofatrans-missioncorridoringeneralwillhaveaminimalimpactonforestry.Presentresidentialareaswillbeunaffectedbyanyofthealternativecorridors;potentialresidentialareasadjacenttoanexistingtransmissionlinewillaccommodatethemselvestoitspresence.Thevoltageofthetrans-missionlineprecludesdirectservicetosmallcommunities;thesewillhavetobeservedbylowervoltagedistributionlines,emanatingfromexistingorfuturemajorsubstations.Thepotentialforservicetosmallcommunitiesisasignificantimpactinthatthesecommunitiesmaystronglydesiretotapthetransmissionline;iftheyareservicedbythetransmissionline,theywillessentiallybecomepartoftheinterconnectedsystem.Sincethecostofpowerwillmostlikelydecreaseinthesecommunitiesafterinterconnec-tion,somelocalgrowthcanbeexpanded,dependingonwhatdegreetheavailabilityandcostofpowerwasalimitingfactortogrowth.Theexistenceofatransmissioncorridormaytendtoattractfuturecorridors;toaconsiderableextent,thisisabeneficialimpactinthatitismoreeconomi-calforrights-of-waytobesharedortobeadjacent;thereisalessenedlikelihoodoflargeareasofwildernesstobecutintoamultitudeofsmallerareasbyredundantrights-of-way;andthepossibilityexistsfor"symbiotic"useofaright-of-waybytwodifferenttypesofutilities.Examplesaretheuseofaccessroadsfortransportationandtheelectrificationofrailroadsandpipelines.Incorridorslimitedbyphysicaland/orland-useconstraints,suchastheNenanaCanyonthroughtheAlaskaRange,proliferationofrights-of-waywillleadtocongestion;incasessuchasthis,itismostdesirabletosetafuturepatternbyattemptingtoutilizeexistingcorridorstominimizepotentialcongestion.Oneofthemostsignificantunavoidableadverseimpactswillbeuponscenicquality.Atransmissionlinewillalwayscauseadetrimentalimpact;thedegreeofthisimpactisdeterminedbythevisibilityandobtrusivenessofthetransmissionlineasseenbythemajorityoftheviewers.Sincemostoftheviewersofthealternativecorridorswillbeontheexistingtranspor-tationroutes,itisinferredthatincreasedvisibilityandobtrusivenessfrom However,itisimpossibletohideanylinefromallviewersfromalldirections.Anytransmissionlineiseasilyvisiblefromtheair;placingalineawayfromaroadtohideitfrommotoristswillnotconcealitfromhunters,hikers,andcampers,towhomthelinemaybeespeciallyobtrusive.Thisdilemmabecomesmoresevereinopencountry,partic-ularlyinscenicsurrounds.Insummary,adverseenvironmentalimpactswillbe:-clearingofvegetationfromasmuchas3747acres.-subsequentperiodiccontroloftheregrowthontheclearingcreated.-permanentremovalofvegetationfromtowerbases,accessroads,andanyfuturesubstationstobeaddedtothesystem.-impactstosoilfromconstructionandmaintenanceoperations.-impactstofisheriesinclearwaterstreamsaffectedbyconstructionandmaintenance.-impactstowildlife,bothbeneficialandadverse,stemmingfromtheaboveeffectsofconstructionandmaintenance.-visualimpactstoscenicandrecreationalresourcesfromTalkeetnanorthtoHealy.-effectsonairqualityduetoburningofslashresultingfromclearingoperations.AppendixI1-95 AppendixI1-96RELATIONSHIPBETWEENSHORT-TERMUSESOFTHEENVIRON1tffiNTANDLONG-TERMPRODUCTIVITYThetransmissionlinecanbeassumedtohaveaverylonglife;aslongasloadsareexpectedtoincrease,astheyare,andaslongastheUpperSusitnaprojectisaviablesourceofpower,thetransmissionroutecanbeconsideredoperative.Individualcomponentswillbereplaced,anditisforeseeablethatthelineitselfmaybeupgradedtohighervoltagesandcapacity,butitwillstillbeessentiallythesametransmissionsystem.Thebulkoftheimpactsontheenvironmentofthelinewillbeencounteredduringtherelativelyshortconstructionphase.Ofthelong-termeffects,somewouldterminateimmediatelyorshortlyaftertheretirementoftheline.Someoftheseeffectswouldbethosespringingfromaccessroadmaintenance,vegetationcontrol,'noiseandelectromagneticinterference,(seeExhibitI"Hazards")andvisualimpact.Otherimpactswillbe"imprintedllintotheenvironment.Wildlifepatternsmayhavebeenaffectedbycontinualhuntingorhabitatmodification;thesepatternswilllingerforaconsiderabletimeafterapossibleremovaloftheline.Vegetationpatterns,alteredbycontinualmaintenanceorintroductionofgrassesorothernonnativeplants,maycontinueforaverylongtime.Uncheckedregrowthoftheclearingwilleventuallyresultinsuccessionalvegetationclosertothestageofthesurroundingforests;thisregrowthwillentailhabitatmodificationsoppositetothosecausedbytheoriginalclearing,butofcourseoveramuchlongertimeperiod.Theaboveassumesthatthetransmissionright-of-waywillretainitsoriginalfunctionforthelifeoftheproject.However,thisright-of-waymayinfluencelandusepatternsthat,likevegetationpatterns,willlingerafterthetermoftheactualtransmissionline.Theright-of-waymayassumethefunctionofatransportationroute;thistransport-ationroutemayeventuallyhavemoreimpactthantheoriginaltransmissionlineandevenoutlivetheline.Otherrights-of-waymayberoutedadjacenttothetransmissionline,thussettingaregionalpatternofcorridorsthatagainmayoutlivethelifetimesoftheoriginalutilities.Atransmissionlinewhichpresentlypioneersaright-of-wayintoundevel-opedareasmayimprintapattern,whichalthoughitmightshiftandfluctuatesomewhat,willdeterminefuturelanduseandtransportationandtransmissionnetworksforthatareafarbeyonditsownlifetime.Thiseffectissimilarforotherrights-of-waywhichpioneerlargeundevelopedareas.AgoodexampleofthisistheAlaskaRailroad,whichisnowparalleledbydistributionandtransmissionlinesandahighway,andwhichresultedinthecreationofseveralsmallcommunitiesalongitslength. Anothereffectonthelong-termproductivityoftheareabythetransmissioncorridorwouldspringfromtheinterconnectionoftheelectricpowergridsofthetwolargestpopulationcentersintheState.Interconnectionwouldenableuseofthecheapestgenerationandthemaintenanceofsmallerreservecapacity,whileatthesametimeresultingingreaterreliabilityforbothsystems.InterconnectionwouldassumeanimportancenearlyasgreatasthefunctionofdeliveryofUpperSusitnapower.NewpopulationcentersarisingintheRailbeltareawouldbeaidedbyproximitytothisinterconnectedsystem.Thegrowthofenergy-intensiveheavyindustryalongthecorridorduetotheavailabilityofpowerispresentlyunlikely;thisisduetothehightransportationandlaborcostsofthearea,whichwouldoutweightheadvantageoftheavailabilityofrelativelycheappower.TheconstructionofaninterconnectedpowersystemfortheRailbeltisaresponsetotheincreaseddemandforelectricpower.Initself,theavailabilityofpowerisnotenoughtoinducegrowthofanarea;otherfactors,someofwhichareintra-andinter-regionaltransportation,theavailabilityoflabor,theexistenceofamarketformanufacturedgoods,produce,and/orrawmaterials,mustexistalsotospurregionalgrowth.Theseotherfactorsareprobablymoreresponsibleforgrowththantheavailabilityofpower.TherearenoimportantpotentialhydropowersitesclosetothealternativecorridorsexcepttheWoodCanyonsite.TheviabilityofthisprojectmaybeenhancedbytheexistenceofthetransmissionroutewhichfollowstheRichardsonHighwayroute.However,otherfactorssuchaslargesizeofthepotentialprojectandenvironmentalimpactsoftheWoodCanyonprojectreducetheprobabilityofthisprojectbeingspurredonbytheexistenceofanalternativecorridor.TheproposedHealy-McKinleyPa.rk25kvdistributionlinemaybeaffectedbytheNenana-lcorridor.Thedistributionlinewilladdanotherright-of-waytoanarrowcanyonalreadyoccupiedbytwotransportationlines.Theconstructionofatransmissionlinecouldremovethenecessityofpartofthisdistributionline;atapatMcKinleyParkcouldservethisareawithpowerfromtheUpperSusitnaProject.However,ithasyettobedeterminedifthecostofalow-loadtapatMcKinleyParkwillprovemoreeconomicalthananextensionofadistributionlinefromHealy.Theproposed230kvCEAtransmissionlinefromPointMacKenziearoundKnikArmmayprovideanothermeansofconnectionoftheSusitna-lcorridortotheAnchorageareainconjunctionwiththeexistingsubmarinecablesatPointMacKenzie.AppendixII-97 AppendixI1-98IRREVERSIBLEANDIRRETRIEVABLECOMMITMENTSOFRESOURCESThematerialsdirectlyusedintheconstructionofthetransmissionlineandaccessroadswillbeirretrievablycommittedforthelifeofthetransmissionline.Thesematerialsincludethealuminumandsteelinthetowers,aluminumandsteelinthecablesandguys,insulators,steelculverts,gravelandconcrete.Ofthese,aluminumandsteelhavescrapvalueandcanberecycled.Maintenancevehicleswillbeirretrievablycommitted,sincetheirresalevalueafterfullusecanbeexpectedtobelow.Thefuelexpendedonconstructionandmaintenanceisirretrievablycommitted,asareotherchemicals,suchaspaint,ifsteeltowersaretobecoated,andherbicides,ifchemicalcontrolofvegetationisused.Thelandoccupiedbytheright-of-wayisirreversiblycommittedforthelifeoftheproject,althoughitcanreverttoitsoriginaluseorsomeotheruseafterretirementoftheline.Thislandcan,forthemostpartbeusedforotheractivities,suchasrecreation,access,oragriculture.Thisis,however,atthediscretionofthelandownerorland-managingagency.Landusepatternsmaybepermanentlyaffectedbythepatternoriginatedbythetransmissioncorridor,witheffectsoutlivingtheoriginaltrans-missionline.Irreversibleecologicalchangesmayresult,dependingupontheamountofclearingorlarge-scalechangeimposeduponanareabyaright-of-way.Mostofthesechanges,suchasthemaintenanceofsuccessionalvegetationinanotherwiseclimaticforest,willeventuallyreverttotheiroriginalcondition,afterretirementofthetransmissionline,althoughthismaytakeaconsiderableperiodoftime.Mineralextractionmaybeaffectedbythelocationofthetransmissionline;sucheffectsprobablywilllastforthelifetimeoftheline,unlessthelineislaterre-routedaroundorebodies.Thiswouldnotbepracticalforlowunit-valueminerals,suchassandandgravel.Inadvertantdisruptionofundetectedarcheologicalsiteswouldresultinirreversibledamagetosuchsites,reducingtheamountofinformationobtainableandtheirhistoricalorarcheologicalvalue.Discoveryofunharmedsitesduringconstructionwillbeabeneficialeffect,however.AllsitesdiscoveredduringconstructionwillbesalvagedasprescribedbyExecutiveOrder11593andPublicLaw93-291,anamendmenttotheReservoirSalvageActof1960.Thelaborspentinconstruction,operation,andmaintenanceofthetrans-missionlineisirreversiblycommitted,asarethesecondaryeffectsoftheincreasedemploymentafforded. MATERIALSANDLANDCOMMITTEDConduc-Struc-}.;faximumLengthtors1/tures2/ROW3/Clearing4/ProposedSystemPlanmilesTon Tonacresacres-----------Susitna-l:345-kv-DC1364,62413,6682,3082,308Susitna-l:345-kv-PSC4,62416,6844,6164,616Susitna-2:345-kv-DC1404,76014,0702,3762,376Susitna-2:345-kv-PSC4,76017,3604,7524,752Susitna-3:345-kv-DC1294,55613,4672,2741,900Susitna-3:345-kv-PSC4,55615,9964,5483,800Susitna-4:345-kv-DC1475,06614,9752,5292,257Susitna-4:345-kv-PSC5,06618,2265,0584,514Matanuska-l:345-kv-DC2589,01026,6334,4972,817l\htanuska-l:345-kv-PSC9,01031,9928,9945,634Matanuska-2:345-kv-DC38513,05638,5926,5163,869Matanuska-2:345-kv-PSC13,05647,74013,0327,738Nenana-I:230-kv-DC1985,10810,6923,0001,439Nenana-I:230-kv-PSC5,10813,1446,0002,878Nenana-2:230-kv-DC2205,67611,8803,3331,500Nenana-2:230-kv-PSC5,67614,5086,6663,000Nenana-3:230-kv-DC2315,96012,4743,4501,318Nenana-3:230-kv-PSC5,96015,1906,9002,636Nenana-4:230-kv-DC2235,75312,0423,3781,182Nenana-4:230-kv-PSC5,75313,8266,7562,364Nenana-5:230-kv-DC2125,47011,4483,2121,364Nenana-5:230-kv-PSC5,47013,1446,4242,728Delta:230-kv-DC2807,22415,1204,2421,727Delta:230-kv-PSC7,22417,3608,4843,4541/Assumesterrain.2/Assumesterrain.3/Assumes4/AssumesRailandPheasantconductors;canbe10%greaterinroughsteelfree-standingtower;canbe10%greaterinroughR.O.W.widthof140'for345kv,and125'for230kv.totalclearingforfullwidthofright-of-way.DC=DoubleCircuit;SC=SingleCircuit;PSC=ParallelSingleCircuitAppcnuxI1-99 MATERIALSANDLANDCOMI."lITTEDConduc-Struc-MaximumLengthtors1/tures2/ROW3/Clearing4/AlternateSystemPlanmilesTonTonacresacresSusitna-l:230-kv-DC1363,5097,3442,0602,060Susitna-l:230-kv-PSC3,5098,4324,1204,120Susitna-2:230-kv-DC1403,6127,5602,1212,12]Susitna-2:230-kv-PSC3,6128,6804,2424,242Susitna-3:230-kv-DC1293,4577,2362,0301,697Susitna-3:230-kv-PSC3,4577,9984,0603,394Susitna-4:230-kv-DC1473,8448,0462,257 2,015Susitna-4:230-kv-PSC3,8449,1144,5144,030Matanuska-l:230-kv-DC2586,837]4,3]04,0152,515Matanuska-l:230-kv-PSC6,837]5,9968,0305,030Matanuska-2:230-kv-DC3859,90720,7365,8183,454Matanuska-2:230-kv-PSC9,90723,87011,6366,908Nenana-I:230-kv-SC1982,2546,1383,0001,439Nenana-2:230-kv-SC2202,8386,8203,333],500Nenana-3:230-kv-SC2312,9807,1613,4501,318Nenana-4:230-kv-SC2232,8766,9133,3781,182Nenana-5:230-kv-SC2122,7356,5723,2121,364Delta:230-kv-SC2803,6128,6804,2421,7271/Assumesterrain.2/Assumesterrain.3/Assumes4/AssumesRailandPheasantconductors;canbe10%greaterinroughsteelfree-standingtower;canbe10%greaterinroughR.O.W.widthof140'for345kv,and125'for230kv.totalclearingforfunwidthofright-of-way.AppendixI1-100DC=DoubleCircuit;SC=SingleCircuit;PSC=ParanelSingleCircuit OTHERALTERNATIVESTOTHEPROPOSEDACTIONAlternativecorridorshavealreadybeendiscussedandcomparedontheprevioussectionsandonthematrixesintheappendix.Inthissection,alternativestobasicassumptionsoftheproposedtransmissionlinewillbediscussedalongwiththealternativeofnon-construction.SharingofRights-of-WayTheassumptionismadeintheproposedandthealternativecorridorsthatanentirelynewright-of-waywillneedtobeobtainedfortheentirecorridor.Sharingright-of-waywithanotherutility(notnecessarilyelectrical)mayobviatemanypotentialimpactsinthataccessmayalreadyexist,reducingconstructionactivitysomewhat,andthatpioneeringofnewcorridors,withattendantproblems,isnolongernecessary.Theproposedtransmissioncorridorcouldadjoinorsharetherights-of-wayoffivetypesofsystems:otherelectricaltransmission,communica-tion,pipelines,railroads,andhighways.Althoughthebenefitineachcaseisasavingsintotallanduse,theadverseimpactsuponthesefivesystemsvary.Electricaltransmissionsystemsthatarejointlyusingoneright-of-waywillsufferareductioninreliability,inthatacatastropheaffectingoneline,suchasseismicactivity,isverylikelytoaffecttheother.Safetyduringmaintenancewilldecreasesomewhat.Jointuseofanexistingcommuniciationright-of-waywillentailpossibledamagetotheexistingsystemduringconstructionofthetransmissionline.Steadystatenoisemaybeinducedintothecommunicationline;thecommunicationlinewillalsobemorevulnerabletofaultandlightningdamage.Inthecaseofburiedcommunicationcables,erosionwilloccurunlesscorrectivemeasuresareused.Pipelinesaresubjectedtocorrosionriskalso.Thehazardsofconstructiondamage,shockandfiresorexplosionwillexist.Railroadswillbesubjectedtoshockandfirehazards.Communicationsmaysufferinterference,andinthecaseofelectricsignals,inducedcurrentmaycausefalsecontrolsignals.Alonghighways,transmissionlinescancontributetoradioandaudiblenoise,andinthecaseofaccidents,cancauseafireandshockhazard.Inthecaseofjointuseofrailroadandhighwayrights-of-way,theriskofaccidentsonthesesystemsaffectingtheintegrityofthetransmissionsystemmustalsobeconsidered.AppendixI1-101 AppendixI1-102Theaboverisksareconsideredwithnocompensationormitigation.Forinstance,corrosionofcablescanbecontrolled,ascaninducedcurrents.Properconstructiontechniqueswillgreatlyminimizeriskofdamage.Effectssuchasaudiblenoiseandresultingrisksoffireandexplosionfromaccidentscannotberesolvedwithjointright-of-wayuse.However,theuseofabufferstripbetweenright-of-waywillnotentailasavingsinland;inthecaseofadjoiningorpartialoverlapofrights-of-waysrequir-ingclearingthroughforest,theuseofabufferofstandingtreeswillrealizenosavingsinclearing.Notallrights-of-waysarevisuallycompatible;forinstance,sharingofright-of-waywithamajorhighwayortrailsystemswillcauseanunacceptablescenicimpact.Forhighways,thisincompatibilitymustbeweighedagainsttheadditionalscenicvisualimpactofviewingtheparallel,butseparaterights-of-way.However,utilitiesnotdirectlyinvolvinghumantransportationorthoseincommercialorindustrialsurroundingsaresuitedforright-of-waysharingparticularlyiftheutilityisanexistingtransmissionline.OntheproposedcorridortoFairbanks,theGoldenValleyElectricAssocia-tionownsa138kvtransmissionlinefromHealytoEster.Itispossibletocombinethislinewiththeproposed230kvdouble-circuitlinefromDevilCanyonbyupgradingtheproposedlineto345kvdouble-circuitandaddingenoughwidthtomakea140footwideright-of-way.Thiswouldbeamoreefficientuseoftheland,alongwiththeeliminationofredundancyofparalleltransmissionlines.Anotherexistingright-of-waywhichcouldbesharedisthatoftheAlyeskaPipeline.Thisisaright-of-waywithanexistingroadfornearlyitsentirelength;useofthisutilitywould,however,entailalongertransmissionline.Thepumpingstationsalongthepipelineareplannedtooperatewithaportionofthetransportedoil;however,ifthestationsweretobeelectricallyoperated,theycoulddrawpowerfromanadjacentdistributionlinewhichtapsthetransmissionline.Extrawidthwillneedtobeobtainedfortheright-of-wayifthetransmissionlineweretofollowthepipeline.Thefeasibilityofhavingindividualtapstoservethepumpingstationsislow,duetotheinordinateexpenseinvolved.Oneutilityright-of-waycloselyfollowstheproposedtransmissioncorridorfornearlyitsentirelength.ThisistheAlaskaRailroad,ownedbytheFederalGovernmentandoperatedbytheDepartmentofTransportation. AppendixI1-103Presently,therailroadisoperatedbydieselmotors;ifelectricmotorsweretobeused,powercouldbetappedfromanadjacentpowerline.However,duetoarelativelynarrowright-of-waywhichatransmissionlinecouldnotsimultaneouslyoccupy,theright-of-waywouldneedtobedoubledonwidth,creating,ineffect,twoimmediatelyadjacentright-of-ways.Thus,therewouldnotbethesavingsofright-of-wayastheprevioustwocases.TheAlaskaRailroadcarriesmainlyfreight;in1973,therailroadoperatedover1800freightcarsand54passengercars.Therewillbesomeobjectiononthepartofthepassengercomponenttotheextremeclosenessofamajortransmissionlinefor250miles;how-ever,thisismuchlessofanimpactthanifthelineweretocloselyparalleltheAnchorage-Fairbankshighwayforthesamedistance.T.Y.Lin(intheNorthernEngineer,Vol.5,No.4)proposestheconstructionofIntegratedPipelineTransportation,acoalescenceofseparatebutparalleltransportationcorridorsintooneintegratedstructuretominimizeenvironmentalimpacts,economizeonconstruction,andincreaseefficiencyofserviceandmaintenance.Itispossibletointegratetransmissionlinesintosuchatransportationsystem,andwouldresultinthebestuseofthelandandtheleastimpacts.However,thepresenceofseveralexistingtransportationroutesprecludeconstructionofsuchintegratedtransportationsystems;theyaremostfeasibleinopeningupnewcorridorsofsignificantlength,andthissituationisnotforeseeableintheRailbelt.Also,atransmissionlineintegratedintosuchasystemwouldrequiretechnologysimilartothatrequiredbyanundergroundcable,thenextalternativetobediscussed.UndergroundTransmissionSystemsThisdiscussionwilllimititselftothepresenttechnologyoftransmissionsystems;potentialcapabilitieswillbediscussedattheendofthissection.MuchofthismaterialisabstractedfromtheBonnevillePowerAdministrationsdraftFiscalYear1976ProposedProgramEnvironmentalImpactStatementUndergroundtransmissionshavebeenfoundtobepracticalintwotypesofsituations;oneinwhichthecostsofanundergroundsystemarelessthananoverheadone,suchasinareasofveryhighright-of-waycostsorwherealargesavingsinlinelengthispossible,suchaswithsubmarinecables.Theothersituationisthatinwhichanundergroundsystemhashighsuitability,suchasentrytosubstationsincongestedareasoreliminatingthehazardsofcriticalcrossings,suchasothertransmissionsystems,andtoeliminatehazardstoaircraftnearairports.Neitherofthesetwogeneralsituationsexistsforanyappreciablelengthalongtheproposedcorridororanyofthealternatives.Althoughunder-groundlineswillalmosteliminatesomeimpacts,suchasvisualimpacts,theywillproduceotherimpactsnotnormallyassociatedwithoverheadsystems. AppendixI1-104Insomecases,theuseofundergroundtransmissioncanbejustifiedtoreducevisualimpactswheretheseimpactsarejudgedtobegreaterthantheadverseimpactsofundergrounding.Suchasituationistypicalinthosehighlyscenicareaswherethetransmissionstructureswouldeitherbesilhouetted,highlyvisible,orhighlyobtrusive,yetwheretheaccessroadandtrenchingscarofanundergroundcablewouldnotbeoverlyvisible.Thissortofsituationwillruleoutcanyonsandotherhigh-reliefareas,butwillfavorrelativelyflatland.Thegreatestvisualdifferencebetweenundergroundandoverheadtrans-missionisobviouslythelackofthetransmissionstructures.However,anundergroundsysteminallcaseswillrequirenotonlyanaccessandconstructionroad,butalsoatrenchwhichwillbevisibleforquitesometitLeafterconstruction.Overheadsystems,however,canbebuiltwithouttheneedforanaccessorconstructionroad,andtheonlyexcavationneededwillbeforthetowerfoundationsspacedoutatarateoffourorfivetoamile.Ifthelocation,design,andconstructionofanoverheadsystemareproperlyspecified,theaccessroadandclearingwillbeasvisible,andusuallymorevisible,thanthestructuresthemselves.Whereclearingisnotneeded,themostvisiblecomponentwillthenbetheaccessroad,andasindicated,eventhisneednotbeconstructedforanoverheadsystem.Incontrast,anundergroundsystemwillalwaysneedaclearinginanyareaandwillalwaysneedaconstructionroad.Thus,anundergroundsysteminrollingorsteepterrainmaywellbemorevisiblethananoverheadsysteminthesesituations.Forthisreason,coupledwiththeseismicrisktobediscussedbelow,itisnotrecommendedthatthesectionofcorridorthroughtheAlaskaRangebeunderground.Amajorfactorintheuseofundergroundsystemsisthecost.Transmissionsystemsareusuallydesignedtomeetgivenrequirementsfortheleastcost;inalmostallsituations,overheadlineswillmeetsystemrequirementsatalowercostthanundergroundcables.TheA.D.LittleReporttotheElectricResearchCouncil(October1971)statesthatundergroundtransmissioncostscanbeashighastentimesgreaterthanoverheadsystems,andinthecaseofcompressedgascablesystems,upto20times.Undergroundsystemsgenerallyinvolvehighermaterialscostforthecableandforassociatedmaterialssuchasinsulatingbackfillorprotectivesheeting.Installationismorecomplicated,involvingexcavationandbackfillingandlaboruseishigherthanforoverheadsystems.Splicing ofa345kvcablecantakeeightormorefullworkdaysandmustbeperformedinspeciallyconstructedair-conditionedrooms,(lIUndergroundPowerTransmissionII,P.H.Rose,Science,Vol.170,Oct.1970).Theoretically,overheadsystemshavemoreoutagesthanundergroundsystemssincetheyareexposedtoweather,vandalism,andaccidents;however,unlessdamageisexceptionallysevere,includingfailureofoneormoretowers,oraccessisrestrictedbyweather,theseoutagesareofshortduration.Faultsinundergroundcablesmayresultinlong-termoutagesuptoseveralweeks;thisresultsfromthedifficultyinlocationofthefault,thetimeinvolvedinexcavationandbackfilling,andthetimeneededtoreplacethefaultedsectionbysplicinginanewsection.Frozenground,whichpersistsforfiveorsixmonths,willretardrepaireffortsmorethanusual.Inseismicallyactiveareas,suchascanbefoundintherailbelt,thereliabilityofundergroundcablesmustbequestioned.Slicingofthecablecanresultfromsettlingorslumpingofthesoil;oil-filledorcompress-gasfilledcablesmayruptureduringsoilmovement.Otheragentscancausefaulting,suchasrodents,corrosion,andsubsequentexcavation.Locationandcorrectionoffaultsinacablefollowingquakesmayinvolveconsiderabletimeandeffortasopposedtothelocationoffaultsinanoverheadsystem.Overheadtransmissionlineshavemoreinherentresiliencythanundergroundcables,andfaultsaremoreaccessibleandeasiertolocate.Environmentalimpactsofanundergroundcablecanbequitesignificantinthatacontinuoustrenchisrequiredandanaccessroadismandatoryfortheconstructionvehiclesandthelayingofthecable.Thebackfilledtrenchmaycauseerosionalproblems,particularlyifthetrenchcutsupordownslopes.Aclearedright-of-waymustbeprovidedformain-tenancevehiclesneededtounearthafaultedline;however,thisclearingneednotbeaswideasforanoverheadsystem.Repairswillinvolvere-excavation,withattendantimpactsduetopotentialerosion.Anundergroundcableinusewillcontinuouslygiveoffheat;thiscanbeveryseriousinice-richpermafrostareas,whichoccurinallofthealternativecorridors.Insulatingbackfillwillretardbutnoteliminatethisheatflow;heat-transferdeviceswillbenecessarytopreventexcessiveslumpingandsettlingofice-richareastraversedbyanundergroundcable.Generatedheatwillalsoaffectthegrowthofvegetation,butthisdoesnotappeartobeasignificantimpact.AppendixII-IDS AppendixI1..,106Duetotheexpenseanddifficultyofinstallation,undergroundcablesareratherinflexiblewithregardstochangingpowerneeds.Theadditionofanothercircuitortheadditionoftapsforlocalcommunitiesisverydifficultincomparisontooverheadsystems,wheretheadditionofanadditionalcircuitwillnotrequireanotherright-of-way,andtheadditionofatapwillnotinvolvetheexcavationofthecable,splicing,andterminalfacilitiesfortheoilorpressurizedgasinsulation.Onhillyterrain,unreinforcedlow-pressure,oil-filledcableissubjecttopossibleruptureduetotheincreasedoilpressureatthelowpointsofcables.Reinforcingandpressurecompensationdevicesarenecessaryinthistypeofcableoverhillyground.High-pressureoil-filledpipecablerequiresacontinuoushighpressuremaintainedbypumps.Thistypeofundergroundsystemisalsosubjecttopressuredifferentialsduetoelevationchanges.CablesfilledwithnitrogenorSF6gascontainconductorswrappedwithoil-impregnatedpaper;onhillyterrain,thisoilwillseeptothelowerends,andsothiscableisonlysuitedforlevelterrain.Cablesinsulatedwithsolidinsulation,suchascross-linkedpolyethylenearesubjecttomanufacturingflaws,suchassmallvoids,whichcanlaterdevelopintoelectricalfaults;theprobabilityoffaultsisproportionaltothevoltage.Usageisusuallylimitedto138kvorlower.Amajordisadvantageofundergroundsystemsisthecarryingcapacitydictatedbycapacitivereactance.Capacitivereactanceisinherentinthecableconstruction,andresultsinachargingcurrentwhichdecreasestheusablepowerthatcanbetransmitted.Thepowerlossinanundergroundcableis25to30timesgreaterthanforanoverheadsystem.1£acableexceedsacertainlength,itstransmissioncapacitybecomeszero.Foracableof115kv,thislengthisabout45miles;fora230kvcablethelengthisabout35miles.Inotherwords,fora230kvcable35mileslong,thelossisequaltotheinputpower.Toovercomecapacitivereactancelosses,andthuslengthenthecriticallengthofanundergroundcable,shuntreactorsmustbeinstalledatperiodicintervalsalongthecable.Theseshuntreactorsarepreferrablylocatedabovegroundforaccessandheatdissipation,andarebasicallyequivalenttoaseriesofminiaturesubstationswiththeattendantsimilarenvironmentalirrpacts,highreductioninreliability,andadditionalcosts. ResearchtoimprovetheundergroundtransmissiontechnologyiscarriedonbytheDepartmentoftheInteriorthroughtheOfficeoftheAssistantSecretaryforEnergyandMinerals,andbyprivateindustrythroughtheElectricPowerResearchInstitute;privateindustryismakingbyfarthegreatercontribution,spending$14millionduringfiscalyear1974ineffortstoadvanceundergroundtransmissiontechnology.OneresultofrecenteffortsistheCompressedGasInsulatedBus(CGIB).Althoughstill10to20timesmoreexpensivethanoverheadtrans-missionandofuntestedreliability,thissytemcanhandle500kvwithacriticallengthofupto200miles,atenfoldimprovementoverpreviouscriticallengthsforthisvoltage.Thepotentialadvantagesofsuchasystemincludereducedvisualimpact,noaudiblenoiseaselectro-magneticinterference,smallvolume,simplicityofmaintenance,andpowerhandlingcapabilityapproachingthatforoverheadsystems.BonnevillePowerAdministrationplanstooperatealengthofprototype500kvCGIBnearEllensburg,Washingtonstartingthesummerof1974toaccumulateeA-periencewiththissystem.Eventually,undergroundcablesmaybeexpectedtoequaloverheadsystemsinperformanceandoverallreliability;however,sincemostofthecostofanundergroundsystemisattributabletolabor,thecostdifferentialbem'eenthetwosystemsisnotexpectedtodecreasesignificantly.APAwillnotrecommendundergroundconstructionforthisproject.Thepresenttechnologyforundergroundtransmissionisnotsufficientlyadvancedtoassurereliabilityofserviceforaregionalintertie.APAintendstofollowcontinuingdevelopmentsinundergroundingtech-nology,butthereisnoindicationthatthedisadvantagesofunder-groundingwillbesolvedinthenearfuture.DirectCurrentTransmissionDirectcurrenttransmissionhasbeenusedinseveralcountriesforbulktransmissionofpoweroverlongdistances.Duetothehighercostsofconversion,thistypeoftransmissionisusuallyusedfordistancesof500to1,000milesbet\.'1/eenconverterstations.IfnoitermediatetapsareplannedbetweenthegenerationsiteandAnchorageandFairbanks,thenthe136mileand198milelengthsoftheproposedcorridorsareconsiderablyshorterthantheeconomicaldistances.Intermediatetapstoservepresentlyunconnectedtownandfuturepopulationcentersalongthesecorridorswouldrequireconverterstationsandevenshortertrans-missionlengths.AppendixI1-107 AppendixI1-108Environmentalimpactsofd-ctransmissionsystemsaregenerallythesameasfora-csystems,exceptthatd-csystemsrequireonlytwoconductorsinsteadofthree,andthuswouldrequireaslightlynarrowerright-of-way.Forundergroundtransmission,theuseofdirectcurrentwillobviatelossesfromcapacitivereactance,andinthisway,enhancetheviabilityofundergroundingwhileimposingtheadditionalcostsofconvertersateachendofthecable.Theuseofd-cinundergroundsystemswillnotlowertheinstalledcostpercable,norwillitenhancereliability.Theneedforonlytwocableswilllowerthetotalcostversusa-ctransmission,andifonecableisfaulted,theothercanfunctionathalf-capacitywithpropergrounding.Thelimitationsofd-ctransmissionpresentlyaregreatenoughsothatitcannotberecommendedfortheUpperSusitnaRiverProject.However,technologicaladvancesmayeventuallyprovideacheaperalternativetothepresentconverters,andthusprovidetheflexibilitypossessedbythea-csystem.AlternativeSystemPlansAlternativeVoltages:Theproposedsystemplanspecifiesa345kvdoublecircuitlinefromthegenerationsitetoAnchorageanda230kvdoublecircuitlinefromthegenerationsitetoFairbanks.TheIITransmissionReportlldiscussesanalternativesystemplanwith.a230kvdoublecircuitlinetoAnchorageanda230kvsingleCircuitlinetoFairbanks.Fordesigndetails,refertotheIITransmissionReport".Theright-of-waywidthfor230kvis125feet;for345kvitis140feet.Doubleandsinglecircuitlinesofthesamevoltagerequireidenticalwidths.Thestructuresneededfor345kvareslightlylargerthanthosefor230kv,andinsomecases,maybemorevisible,butthisisunlikely.Theenvironmentalimpactsofthisalternativevoltagewillbeessentiallyidenticaltotheproposedone.Therewillbesomemajordifferences,however,intheamountofright-of-wayandclearingforallthea.lternativecorridorsfromthegenerationsitetoAnchorage,andintheamountsofmaterialscommittedforallthealternativecorridors. DoubleCircuits:StackedorParallelSingleCircuits:BothoftheabovealternativevoltageswillcallfordoublecircuitstoAnchorage,andonewillrequireadoublecircuittoFairbanks.IntheDescriptionoftheProposedActionsection,theuseofstackeddoublecircuitswaspremised.Inthisarrangementofcircuits,bothcircuitsoccupythesameright-of-wayandaresupportedbythesametowers,suchasshowninFigure2.However,anotherarrangementofcircuitswillbeproposedforthosesegmentsofthecorridorrequiringaddedreliability.Sincetheproposedprojectwillbearegionalintertie,thereisconcernforreliabilitybytheutilitiesservingtheAnchorageandFairbanksareasandconsultedagenciessuchasBonnevillePowerAdministrationandtheBureauofReclamation.Becauseofthisconcern,mostoftheproposedcorridorwillrequireamorereliablearrangementofcircuitsthanthestackeddoublecircuit.Thisalternativearrangementofcircuitsforeithervoltageplanwillcallfortwoparallelsinglecircuitsinsteadofastackeddoublecircuit.Thiswillnotaffectthesystemplan,asineithermethod,adoublecircuitwillbeprovidedwhereneeded.However,aparallelsinglecircuitwillrequireuptotwicetheacreageandclearingofastackeddoublecircuit,whichrequiresnomoreacreageorclearingthanasinglecircuit.Themajoradvantageofsuchamethodwillbetheextrareliabilityprovidedbyaredundanttransmissionline;outagesfromdroppedtowersordroppedconductorsshortinganothercircuitareeliminated.Thevisibilityofaparallelsinglecircuitlinewillbedifferentthanastackeddoublecircuit;thetowersareshorterthandoublecircuittowers,butthenumberofstructurespern:ileistwiceasmuch.Inaddition,theclearingistwiceaswide.Theextrareliabilityofaredundanttransmissionlinemaynotbenecessaryfortheentirelengthofacorridor,butonlyinthoseareasofhighriskfromwinds,slides,orseismicactivity.Inthetableonpages108-109,thematerialsandlandcommittedforeachalternativecorridorandbothalternativesystemplansarepresented.Foreachdoublecircuitsystem,theequivalentmaterialandlandfortheparallelsinglecircuitsystemispresentedalso.Itmustberememberedthatinthistable,itassumedfortheparallelsinglecircuitsystemthattheentirecorridorwillusethissystem,theactualmaterialsandlandscommittedwillprobablybeless.AppendixI1-109 AppendixI1-110CommonorDividedRight-of-wayforParallelSingleCircuits:Whentwoparallelsinglecircuitsareused,theycanbelocatedeitheronacommonright-of-wayofawidthuptotwicethewidthrequiredforasinglecircuit,ortheycanbelocatedalongtwototallyseparaterights-of-way.Theadvantagesofacommonright-of-wayareeconomyofconstructionandmaintenanceinthatonlyoneaccessroadneedbebuiltandmaintained;andabetteruseofthelandinthatunusuablestripsoflandbetweenrights-of-waywillbeminimized.Problemsrelatedtoincreasedaccesswillbelesswithacommonaccessroadthanwithduplicateaccessroads.Thereliabilityofparallelsinglecircuitswill.beincreasedifseparaterights-of-wayareusedonthetheorythatnaturaldisastersaffectingonecircuitwillprobablyaffecttheotheroneimmediatelyadjacenttoit.Separationofthetwocircuitswillincreasethechanceofsurvivalofatleastoneofthecircuits.Inthiscase,thedistanceofseparationisunderstoodtobeontheorderofuptoseveralmiles;bothcircuitswouldremainthesamecorridor.Anadditionaladvantageofseparaterights-of-waywillbeflexibilityforlocalserviceforcommunitiesenroute,andforlocalservice,assumingitisdecidedthatacommunityinthevicinityofthecorridorofa345kvdoublecircuitlinewillbeconnectedtothetransmissionsystem.Iftwoparallelsinglecircuitsareused,oneright-of-waycanberoutedtoprovideacloserapproachtothecommunity,reducingthelengthofdistributionline.Theuseofparallelsinglecir-cuitsforconnectiontotheAnchorageareawillbediscussedunderAlternativeEndpoints.Acommonright-of-waymayinsomeinstancesrequireonlyhalftheclearingrequiredofseparaterights-of-way;inmostcases,however,theamountsofclearingwillbenearlyequal.Bothwillrequirethesameamountsofmater-ialandlaborinconstruction.Iftwoparallelsinglecircuitsareused,bothcommonandseparaterights-of-waymaybeused.Instretchesofhighriskofcatastrophicfailure,suchasslideandseismicareas,separaterights-of-wayarepreferrable.Inareasoflowriskofnaturaldisaster,economyofconstructionandmaintenancewouldindicateacommonright-of-way.Thecostofparallelsinglecircuitconstructiononacommonright-of-wayisincludedinthe"TransmissionReport.IILaterdesignstudieswillgointogreaterdetailontheproblemofreliability. AdditionalTransmissionLinesAlongOtherCorridors:Anotheralter-nativeistheconstructionoftransmissionlinesalongtheMatanuska-lorMatanuska-2andtheDeltacorridorsinconjunctionwiththeproposedsystem.Thesecorridorswouldnotnecessarilybeconstructedatthesametimenorsamevoltagesorcapacitiesastheproposedsystem.Themainadvantageofsuchasystemwouldbetheincreasedreliabilityofredun-dantlines,andtheinterconnectionofcommunitiesalongtheGlennandRichardsonHighways,theCopperValleyElectricAssociationandtheinterconnectedsystemproducedbytheproposedsystemplan.TheenvironmentalimpactsoftheseadditionalcorridorswouldessentiallybethesameasthoseoutlinedforMatanuska-landMatanuska-2andtheDeltacorridors.However,theamountsofright-of-way,clearing,andmaterialscommittedwilldependuponthevoltageandcapacitiesoftheseadditionalcorridors.Fordetails,refertotheIITransmissionReport.IIAlternativei'.1ethodsofConstructionandMaintenanceAccessRoadsversusHelicopterConstruction:ItisproposedtobuildpermanentaccessroadsforthelengthofboththeproposedSusitna-landNenana-lcorridorswiththeexceptionofunsuitableareas.Theseareaswillbeconstructedbyhelicopteraccess.Whereanaccessroadisused,itwillbebrokenatmajorstreamcrossings,stretchesofpoorsoilorbrokenterrain,orwhereitwouldresultinexcessivevisualdegradation.Themajorsectionsoftheaccessroadwilltieintoexistingtransportationcorridors.Thesebreaksintheaccessroadwillalsoservetolimitaccess.Theadvantagesofanaccessroadoverhelicopteraccessare:lessexpensepermileovermostterrain;easeintransportationofmachineryandmaterials,towererection,stringingofconductors,andremovalofmerchantabletimber;morereliabilityofaccessformaintenanceandinspection;andmultiple-useofcorridor.Disadvantagesofanaccessroadare:increasedmaintenanceproblems;unauthorizeduseofaccessroad;potentialincreaseinerosionandsedi-mentation;increasedvisibility,andmoreclearingrequiredwithsubse-quentimpacts.Sinceneitheralternativemethodissuitablefortheentirelengthoftheproposedcorridor,theproposedmethodofaccessisthatwhichwasjudgedtobemostsuitabletothelocation.AppendixII-Ill AppendixI1-112WinterAccessversusYear-RoundAccess:Transportationofmaterialsandmachineryandconstructionduringwinterwouldeliminatemanyimpactsrelatedtoaccessroadconstructionandtowererection.Withtotalwinterconstruction,theaccessroadwouldnotbenecessary.Winterroadusewilldependuponthetopography,snowdepths,soilmoisturecontent,vegetationcover,andloadedvehicleweights.Twomajorabusesofwinterroadsaretheiruseoverinsufficientsnowcover,especiallywithvehiclesofhighsurfaceloading,whichcandestroythevegetativecover;andtheover-compactionofsnowcausedbyhighsurfaceloadingsindeepersnow,whichresultsinlossofinsulationforsurfacevegetationandamoretenaciousspringsnowpackonthetrackarea.Disadvantagesofwinteraccessandconstructionare:theconstructionseasonwouldberatherlimited;conditionswillbeharshonmenandmachinery;snowandfrozengroundmayinterferewithexcavationandplacementoftowerfootings;thelackofanaccessroadwillaffectthereliabilityofmaintenanceaccess,andwilleliminateanymultiple-useoftheclearing.Consideringthesiteofthisproject,itisnecessarytouseasmuchoftheyearaspossibleinordertocompleteconstructionwithinareasonabletime.Also,givensomeoftheweatherconditionsandthelengthofthecorridors,reliabilityofaccessisimperative,especiallysincethereisnoproposedback-uptransmissionlineincaseofafault.Thus,wheneverpossible,year-roundconstructionwillbeused.Asoutlinedabove,accessroadswillbeusedwheneverindicated.AlternativeMethodsofClearing:Presently,someoftheclearingmethodsusedbytheutilitiesareassimpleasbulldozingoverany andalltreeswithinasetdistancefromthecenterlineoftheright-of-way,insuringenoughwidthforanaccessroad,easeofconstruction,andclearancebetweenfallingtreesandtheconductors.Thismethodisfairlydirect,involvinglittlediscretionbetweenwhatiscleared,andactuallywhatisminimallynecessaryforconstructionandmaintenance.However,thisn:ethodalsoresultsinexcessivedisturbanceofthesoilandunnecessarydestructionofvegetation. Considerablycheaperandlessenvironmentallydamaging,thetechniqueofonlyclearingthatvegetationnecessaryforconstructionandmaintenanceisrecommended.Insteadoftopplingtreeswithabulldozer,selectivecut-tingisused,allowingstumpstoremain.Therearethreemethodsofdisposalofclearedvegetation:salesofmerchantabletimber,burning,orchipping.Allthreealternativemethodswillbeusedwhereapplicable.Withnoaccessroad,machinerycannotbebroughtinforstacking,burning ,orchipping,anddownedtimberwillbeleftalongtheclearing.Saleoftimberwillrequireanaccessroad;someofthetimbercanbeusedinroadconstructionintimberbridgesandcorduroyinmuskeg.Alsointhiscategoryistheofferingoftimbertoanywhowishtoremoveitforfirewood;thiswillonlybesignificantnearsettledareas,andanytimbernotdisposedofinthiswayafterafewmonthswillbedisposedofinotherways.Ifnoaccessroadistobeused,thenopenburningistheonlyavailablemethodofdisposal.Atemporarydeclineinairqualityisinevitable,andopenburning,inanycase,willbesubjecttolocalordinancesoftheaffectedboroughs.Forced-draftburningwillconsiderablyreduceparticulates,butwillrequireanaccessroadforthelargetubburners.Inanycasewhereburningisallow-able,whereanaccessroadwillbebuilt,andwherechippingisnotnecessary,forced-draftburningwillbeused.Inareaswherelarge-scaleburningisprohibited,orwherechippingismoresuitable,thenslashandunsalabletimberwillbechipped.Althoughmostexpensiveandtimeconsumingofthethreemethods,chippinginmanyinstancesispreferable.Wherepermafrostdegradationis.likely,wherethesurfacematofvegetationhasbeenseriouslydisturbedordestroyed,oronpotentiallyerosivesoils,theuseofchipsasaprotectivehumusisindicated.Chipswillprovideameasureofinsulationoverice-richfrozensoils,someprotectionforbaresoils,andalthoughdecompo-sitionratesareslow,anorganicmulchtoaidrevegetation.Sincethechipswilllieontheground,andusuallybesomewhatwet,theywillpresentlessofafirehazardthanunchippedslash.AppendixI1-113 AppendixI1-114Afourthmethodofdisposalistostackslashandallowittonaturallydecompose.Althoughthiswillprovideatemporaryhabitatforsmallmammals,itwillalsoprovidegoodhabitatfordestructiveinsects,providefuelforfires,andreducethevalueoftheclearingasafirebreak.Thus,thisoptionisnotrecommendedintheecosystemsofmoderateanddenseforests,specificallythebottomlandspruce-poplaranddenseuplandspruce-hardwoodecosystems.AlternativeMethodsofClearingMaintenance:Inareasoffastregrowth,someperiodicsuppressionoftallplantsisnecessary.Therearethreemajoralternativemethods:aerialapplicationofherbicide,manualapplicationofherbicide,andphysicalcuttingoftreesandbrush.Aerialsprayinginvolvesthecoverageoflargeareaswithherbicidessprayedfromanairplane,ormorefrequently,ahelicopter.Duetothenon-selectivenatureofapplicationandtheriskofaccidentaloverspraying,sprayingofwaterbodies,andimproperconcentrations,thismethodwillnotbeused.Manualapplicationofherbicidesinvolvesthesprayingoftargettrees,dispersalofpelletsatthebaseoftargettrees,orselectivesprayingofthicketofbrush.Itisrelativelysafefromtherisksassociatedwithaerialspraying,andalsomuchmoreselective.Itcanbecarriedoutduringroutinegroundinspectionsorduringscheduledprogramsofbrushsuppression.Physicalcuttinginvolvestheidentificationanddestructionofdangertreesandtheperiodicsuppressionofbrush.Chainsaws,brushaxes,andmotorizedrotaryaxescanbeusedforthis.Thelaborexpendedisgreaterthanformanualapplicationofherbicide,butissafeforuseadjacenttowaterbodies.Iflargeareasofbrusharecut,theslashmustbeburnedorchipped.Smallamountsofslashwidelydispersedwillnotposeaninsectorfirehazard.Theproposedmethodofcontrolisthemanualapplicationofherbicideswithcuttinginsensitiveareas;aerialsprayingisnotproposed.AlternativeEndpoints:Forthisfeasibilitystudy,itwasnecessarytoassumeendpointstoallowdeterminationcosts,clearing,etc.Thisinnowaywillfinallydefinetheendpointsoftheactualtransmission,justasthelocationofacorridordoesnotattempttolocatetheactualplacementofatransmissionlinewithinthatcorridor.Theactualendpointswillbedeterminedinthefinaldesignstudies. ThechoiceofendpointsoftheNenanaandDeltaalternativecorridorsisrelativelylimitedtothosealreadypostulated--EsterandFairbanks.Unlessnewsubstationsweretobebuilt,thesearetheonlytwofeasiblechoices.TheAnchorageareawillneedadditionaltransmissioncapacity,whethertheproposedtransmissionsystemisbuiltornot.However,thereareseriousproblemsinsupplyingpowertoAnchorage.Presently,powerisbroughtintoAnchoragethroughthesubmarinecablesatPointMacKenziefromthenortheastviatheAPA115kvline,andfromthesouth,whichwillnotbeofconcerninthisdiscussion.ThetwosuppliestoAnchorageviaPointMacKenzieandtheAPAlineovercomethebarrierofKnikArmintwoways:adirectcrossing,andanend-runaroundthenorthoftheArm.Althoughmostdirect,thesubmarinecablesarenotasreliableasanoverheadsystem;thiswasbroughtoutinthefailureofthecablescausedbyadraggingshipIsanchorinthewinterof1974-75.PointMacKenzieisfarclosertothemainloadcenteratAnchoragethanPalmer;thetransmissioncorridorwillcrossrelativelylessdevelopedlandtoapproachAnchorageviaPointMacKenziethanviaPalmer.PowerwouldbemarketeddirectlytoChugachElectricAssociation,andwheeledovertheirsystemtoAnchorageMunicipalLightandPower,HomerElectricAssociation,MatanuskaElectricAssociation,andtheSewardElectricSystem.AnotherpossiblemethodforconnectiontoAnchorage,utilizingthePointMacKenzieendpointwouldbetheoverheadcrossingofKnikArm.PlacingthetowersonpiersacrossarelativelyshallowsectionofKnikArmwouldallowamoredirectconnectiontoAnchorage,avoidingboththesubmarinecablesandthemorecircuitousroutearoundtheArm.However,visi-bilitywouldbehighforthisline,possibleinterferencewithmarineandairtrafficmayresult,andthereisapossibleriskofdamagebypackicetothetowers.CEApresentlyoperatesa138kvlinefromtheBelugagasturbinegenera-tionsitetoPointMacKenzie,designedforupgradingto230kv,andhasproposedanextensionaroundKnikArmwhichwilleventuallytieintoAnchoragebywayofReedSubstation.AnendpointforSusitna-1atPointIvfacKenziecouldusethisproposedlineasanalternateconnectiontoAnchoragealongwiththesubmarinecables.Thiswould,however,bedependentuponauthorizationfortheconstructionoftheextension.DeliverytotheexistingAPAsystematPalmerwouldavoidthelimitationsandriskofthesubmarinecrossingofKnikArm,butwouldinvolvemorecrossingofprivatelyownedland.PowerwouldbemarketeddirectlytoAppendixI1-115 AppendixI1-116AnchorageMunicipalLightandPowerandChugachElectricAssociation.PowerwouldbewheeledovertheCEAsystemtoHEA,SES,andMEA.TheenvironmentalassessmentfortheSusitnacorridorwithanendpointatPalmerwouldbesubstantiallythesameasthatfortheproposedsystem.Mileage,clearing,andotherimpactswouldremainvirtuallythesame.IfthecorridorweretoberoutedalongtheuplandsnorthoftheAnchorage-FairbanksHighway,somewhatbettersoilswouldbeencountered,andmoreprivatelyownedlandandfarmswouldbecrossed.FortheMatanuskaalternativecorridors,therewouldbemoresubstantivedifferences:thecorridorwouldbeabout45milesshorter,andwouldinvolveupto764acreslessofright-of-wayandclearing.Also,lessmaterialswouldbeused,andlesslaborexpendedbyutilizingthePalmerendpoint.Theuseofseparaterights-of-wayforparallelsinglecircuitswouldenabletheutilizationoftwoseparateendpointschosentomaximizeeaseofaCcesstoAnchoragewhileretainingahighdegreeofreliability.Asanexample,onecircuitcouldterminateatthePointMacKenziecableterminal,theothercoulddeliverpowerviatheAPAsystemnearPalmer.OtherpossiblecombinationscouldbedevisedwithendpointsofPalmer,apotentialcause-wayacrossKnikArm,andtheprojectedBelugaextensionaroundKnikArm.Anothervariationonendpointswouldbetheupgradingoftheexisting115kvAPAlinefromPalmertoEklutnatoAnchorage.EitherasinglecircuitorbothcircuitsfromtheUpperSusitnaprojectcouldbebuiltuponthisright-of-wayifadditionalcapacitywasaddedtohandletheoutputoftheEklutnapowerplant.Thefinaldecisiononendpointswillbemadeinlaterdesignstudies,andwillbedependentupontheevolutionoftheexistingtransmissionsystemsinthetimeuntilthefinaldesignstudies.AlternativeLocalServiceAlongtheproposedcorridorsareseveralcommunitiesnotpresentlyservedbythelargerutilities.Thesecommunitiesdependuponlocaldieselgenerationforelectricalpower,andnotallmembersofthesecommunitiescanaffordthehighcostoflocalgeneration.Thesecommuni-tieswilleventuallybeservedwithUpperSusitnapower,eitherbyadirecttapfromtheproposedtransmissionlineorindirectlybyextensionsofexistingdistributionsystems.Sizeoftheload,lengthandcostofthenecessarydistributionsystemextension,anddistancefromotherpresentlyunservedcommunitieswilldeterminewhichofthesetwomethodswillserveacommunity. Acommunity,orclusterofcommunities,relativelydistantfromexistingdistributionsystems,yetclosetothetransmissionsystem,andhavinganexpectedloadoffivetotenmegawatts,willbelikelytotapdirectlyfromthetransmissionline.However,adistributionsystemwillstillbenecessarytodeliverpowerfromthesubstationtothecommunity.CommunitieswitheA-pectedlowloadsmaynotjustifytheexpenseofasubstationforadirecttap;thesecommunitieswillhavetowaitforanextensionofexistingdistribution.NoAction(Non-construction)Indiscussingthealternativeofnon-constructionoftheproposedtrans-missionline,theviabilityoftheUpperSusitnahydroelectricprojectmustbeconsidered,sincetheprimarypurposeofthetransmissionlinewillbetodeliverthegeneratedpowertothemajorcentersintheRail--belt.Inessence,non-constructionofthetransmissionlineimpliesnon-constructionoftheUpperSusitnapowersites.NoactionwillmeanthatthepotentialpoweroftheUpperSusitnawillnotbemadeavailabletotheRailbeltarea.Sinceuseofpowerisprojectedtoincrease,alternatesourcesofpowerwillhavetobeused.Ifpresentplantsareupgraded,thiswillresultintheincreaseduseoffossilfuelssuchascoalandgas.Itisnotlikelythatcostsoffossilfuelswillremainthesame,andtheywillalmostcertainlynotdecrease.Developmentoflarge-scalehydroprojectswillprobablybebeyondthecapabilityofthepresentutilities,sofossilfuelswillbeusedforarelativelylow-priorityusewhereasarenewableresource,waterpower,willgountapped.Ifadditionalpowersitesarerequiredtosatisfyenergyneeds,astheyprobablywillbe,then theywillrequiretheirowntransmissionsystemstodelivertheirpower.Thus,non-developmentoftheUpperSusitnaanditstransmissionsystemwillnothaltfurtherconstructionoftransmissionsystemsbyotheragenciesorutilities,andifnewpowersitestendtobesmall-scaleduetoinabilityofutilitiestodeveloplargehydrosites,thenmoretransmissionlinesmayresultthaniftheUpperSusitnaweretobedeveloped.Anothereffectofnon-constructionwillbetopreservetheinsularanddisconnectedcharacteroftheutilitysystemspresentlyservingtheRailbelt.Atransmissionlinetobebuiltwiththemainpurposeofinter-connectionwouldnotbelikelyinthenearfuture,andtheduplicationandwasteofthepresentsituationwillbeprolonged.AppendixI1-117 AppendixI1-118ACKNOWLEDGEMENTSInpreparingthisEnvironmentalAssessment,theAlaskaPowerAdminis-trationhasworkedinclosecoordinationwiththeAlaskaDistrictCorpsofEngineers.ThisreportwascirculatedinpreliminarydraftanddrafteditionstointerestedFederalandStateagencies,boroughs,utilities,andgroupsforcommentandinformation,manyofwhichprovidedvaluableassistance.Commentsandadvicehavebeengivenbythefollowingagencies,utilities,andgroups:BonnevillePowerAdministrationBureauofLandManagementBureauofReclamationU.S.ForestService,AlaskaRegionNationalParkServiceFishandWildlifeServiceNationalWeatherServiceStateofAlaska:DepartmentofEnvironmentalConservationDepartmentofCommunityandRegionalAffairsDepartmentofNaturalResources-DivisionofParksDepartmentofFishandGameDepartmentofHighwaysFairbanksNorthStarBoroughAnchorageMunicipalLightandPowerDepartmentChugachElectricAssociationGoldenValleyElectricAssociationHomerElectricAssociationMatanuskaElectricAssociationGeophysicalInstitute,UniversityofAlaskaCommonwealthAssociates,Inc.Inaddition,manyindividualshavecontributedvaluableinformalcomments. BibliographyUndergroundPowerTransmission,A.D.LittleReporttotheElectricResearchCouncil,October16,1971.AlaskaRegionalProfiles:South-CentralRegion,theArcticEnvironmentalInformationandDataCenter;TheUniversityofAlaskaandtheOfficeoftheGovernor,StateofAlaska1974.MultimodalTransportation~CorridorsinAlaska:APreliminaryConceptualAnalysis.U.S.DepartmentofInterior,BureauofLandManagement,October1974.2Volumes.TheNeedfor~NationalSystemofTransportationandUtilityCorridorsAcrossFederalLands:AStudyReport(Draft).U.S.DepartmentofInterior,BureauofLandManagement,July1975.2Volumes.EnvironmentalEffectsofHerbicidesResearchProject,K.L.Carvell,EdisonElectricInstitute,NewYork;EElProjectRPI03.The1970NationPowerSurvey,FederalPowerCommission;printedbyGovernmentPrintingOffice,Washington,D.C.,December1971,PartIV.EHVTransmissionLineReferenceBook,writtenandeditedbyProjectEHV,GeneralElectricCompany;published1968byEdisonElectricInstitue.MeasuringtheSocialAttitudesandAestheticandEconomicConsiderationsWhichInfluenceTransmissionLineRouting,P.L.Hendrickson,etaliBattellePacificNorthwestLaboratories,Richland,WA;July1974,NWL-1837:UC-H.EnvironmentalAtlasofAlaska;P.R.JohnsonandC.W.Hartman;UniversityofAlaska,College,Alaska,1969.MuskegEngineeringHandbook,editedbyI.C.MacFarlane;bytheMuskegSubcommitteeoftheNRC-AssociateCommitteeonGeotechnicalResearch;UniversityofTorontoPress,1969.55WaystotheWildernessinSouthcentralAlaska;Nienhauser,Simmerman,Vandel'Laan;MountaineeringClubofAlaskaandTheMountaineers;Seattle,June1972.OregonWeedControlHandbook,OregonStateUniversityExtensionService,Corvallis,April1973.AppendixI1-119 AppendixI1-120ResourcesofAlaska:ARegionalSummary,theResourcePlanningTeam,JointFederal-StateLandUsePlanningCommissionforAlaska,July1974.AVegetativeGuideforAlaska,preparedbytheSoilConservationServiceetal;publishedbytheDepartmentofAgriculture,Portland,1972.EnvironmentalCriteriaforElectricTransmissionSystems,USDA,USDI;U .S.GovernmentPrintingOffice,Washington,D.C.1970.B.H.Baker,IIDidBeetlesDoThat?",AlaskaMagazine,July1974,p.48.A.E.Caswell,C.V.Nazare,R.J.Berger,J.C.TossiofCommonwealthAssociates,Inc.,llGeologyisCriticalinRoutingEHVTransmissionLinesII,ElectricalWorld,December1974,p.54ff.J.A.Heginbottom,"PermafrostandGroundStability",NorthernEngineer,Vol.6,No.4,Winter74-75,p.4.ProposedMt.McKinleyNational~arkAdditions,Alaska:EnvironmentalStatement;AlaskaPlanningGroupvs.DepartmentofInterior,October1974.GeneralConstructionandMaintenanceProgram::EnvironmentalStatementpreparedbyBonnevillePowerAdministration,August1974.GasPipelineDraftEIS;DepartmentoftheInterior,BureauofLandManage-ment,January1975.HerbicideUseonNationalForestsofAlaska:EnvironmentalImpactState-mentpreparedbyU.S/ForestService,Region10,~vlay1975.ProposedElectricDistributionLineExtensiontoMcKinleyPark:DraftEIS;preparedbyDepartmentofInterior,NationalParkService,PacificNorthwestRegion.ReceivedNovember1975.EnvironmentalAnalysisofProposed230kvTransmissionLinefromTeelandSubstationtoReedSubstation;ChugachElectricAssociation,January1975.DraftEnvironmentalImpactStatementfortheCantwell-~JcKinleyParksectionoftheAnchorage-FairbanksHighway;DepartmentofHighwaysStateofAlaska,August1971. "PreservationofHistoricPlacesII,FederalRegister,Vol.40,No.24,February7,1975.IIThreatenedorEndangeredFaunaorFlorall,FederalRegister,Vol.40,No.127,July1,1975."NationalRegisterofNaturalLandmarksII,FederalRegister,Vol.40,No.87,May5,1975,p.19503ff.IIDiscussionofUndergroundingAlternativesinEnvironmentalSupplementsII,draftpositionpaperpreparedbyBonnevillePowerAdministration,February1975.AppendixI1-121 Scaleinmiles10551520_i2555 -'j10Scaleinmile.~..-152CMt.MoKlnleyNationalPark.-)' 55.20-..'rScaleinmile_s___.-251015LAN·D55 )55MilitaryReservationMilitaryReservation 252015VALDEZ-R-I----<.......10NRDScaleinmilesSTATUSo5LANDNRD5555 GalNRD-----~C/)2«NRCI-2.::>0SS~0.:ro?u<::((9.::>.:r0Irt.Ur,14'47./) Scaleinmile_soSTATUSIPALMER-GLENNALLENssNRDi25201510I) ss..~-...-o5ScaleinmilesNRD PHOTOGRAPHSAPPENDIXIEXHIBIT1-3 EXHIBIT1-3PhotographsThefollowingphotogl'aphsdepicttypicalviewsandcriticalpointsalongtheproposedcorridorsandtheiralternatives:Photos1 - 4areillustrationsofCorridorSusitna-1Photos5 -25areillustrationsofCorridorNenana-1Photos26-28areillustrationsofCorridorSusitna-2Photos29-30areillustrationsofCorridorSusitna-3,4Photos31-40areillustrationsofNenana-2,3,4,5Photos41-56areillustrationsofMatanuska-1,2Photos57-69areillustrationsofDeltaCorridorAllphotographsinthisappendixweretakenbyAPApersonnel.ThemajorityweretakeninSeptemberof1974. LowerSusitnaRiverValley.Thisareaischarac-terizedbyextensivemuskegs,intermingledwithbottomlandspruce-poplarforests.Pennafrostisabsentordiscontinuousinthisarea,althoughthesoilsaregenerallypoorlydrained.II1-1 SusitnaRiverValley.Lakesareprevalentandassoc-iatedwithmuskegs,whichsucceedtheminformation.Muskegsaresucceededinturnbyforestsdependentuponwell-drainedsoils.Thethreestagesofsuccess-ionareshownhere.III-2 SusitnaRiverValleynearTalkeetna.Astheterrain·.becomesmorerolling,therelativeamoillltofmuskegbecomesless.III-3 ............ I ~ itf: Town of Talkeetna.This town is at the confluence of the Talkeetna, Susitna,and Chulitna Rivers.The Alaska Railroad can be seen cross- ing the Talkeetna River near the right edge of the picture. .................. I U"I Summit Lake at Broad Pass.Broad Pass is an aptly named feature;a structurally-controlled depression in an otherwise mountainous area. It is the divide for tributaries of tIle Chulitna and Nenana Rivers. ............... I ~ f······ Alaska Range from Anchorage-Fairbanks Highway near Broad Pass,late spring.Vegetation biome is lowland spruce-hardwood.Soils here are basically glacial deposits. ............... I...... Alaska Range from Anchorage-Fairbanks Highway near Broad Pass.Soil here is poorly drained;trees visible are black spruce. ............... I ex> Entering Alaska Range on Anchorage-Fairbanks Highway,north of Cantwell. Concealment of line will be difficult in areas such as this. LookingsouthalongNenanaRivertoUpperNenanaCanyon.TheAnchorage-FairbanksHighwayparallelstheleftbank.Mount!'-1cKinleyNationalParkandtheAlaskaRailroadareontherightbankoftheriver.1II-9 ..................•--'o Nenana River and Sugar MOlmtain,seen from Anchorage-Fairbanks Highway near Yanert.Yanert Fork enters Nenana River near right-hand edge of photo.Visible also is communication line for Alaska Railroad. VeryrestrictedcanyonalongNenanaRivernorthofMcKinleyPark.AlaskaRailroadisoffleft-handedgeofphoto.LandleftofriveriswithinMotmtMcKinleyNationalPark.II1-11 III-12 .................. I....... W Nenana River valley in vicinity of Moody bridge on Anchorage- Fairbanks Highway. 1II-14 ............ I..... U1 Usibelli Coal Mines near Healy.Note the seams of coal in the scarp.This coal is the fuel for the Healy steamplant. ...............,...... 0"1 Nenana River flood plain near Healy.Note the terraces characteristic of the Nenana Valley in this area. ~ ~ ~ I ...J ""-J 138 KV Healy transmission line.Looking south from Anchorage- Fairbanks Highway towards Healy. Guyedtangenttowerinforeground;guyeddead-endtowersinbackground;Healy138K:Vtransmissionline.1II-18 Guyed138KVtowerontheHealytransmissionline.III-19 ---•I'\,)o Nenana River valley,looking south to Alaska Range.Terraces are fairly evident along right backgrotmd. TownofNenana,atconfluenceofTananaRiverandNenanaRiver,whichflowsinfromlowerright.Double-spanbridgeisfortheAnchorage-FairbanksHighway;single-spanbridgeisforAlaskaRailroad.III-21 ............... I N N Alaska Railroad siding along Tanana River at Nenana.Large free- standing tCMer is part of river crossing of Healy 138 KV transmission line. ............... I N W Town of Nenana;frontage on Tanana River.Nenana handles considerable river traffic on the Tanana River. ............... I N .j::>, "Goldstream Hills".On the slopes,the predominant vegetation is birch-white spruce,on poorly drained areas and some north-facing slopes;black spruce predominate. ---•N 01 " View to the west from the "Goldstream Hills".These hills flank the north bank of the Tanana River;the Anchorage-Fairbanks Highway enters them immediately across the river from Nenana,and follCMs their crest to Ester and Fairbanks. ............... I N O"l Clearing for Matanuska Electric Association (~~)distribution line. Vegetation is predominantly poplar and spruce.Clearing was done by uprooting trees with a bulldozer. ...............•N '" Near Honolulu on the Anchorage-Fairbanks Highway.Biomes shown on low brush muskeg in foreground and upland spruce-hardwood in back- ground.Black spruce in foreground are associated with poorly drain- ed soils and/or shallow permafrost tables. LittleCoalCreekinDenaliStatePark.Vegetativebiomeisclassifiedasuplandsprtlce-hardwood.Streamsinthisareaareincisedintoarelative-lygentleplain.1111-28 TalkeetnaRiverneartownofTalkeetna.ThisphotoshowsthedensityandconformityoftheforestofthelowerSusitnaValleyintheTalkeetnaarea.111-29 ............... I Wa Detail of bottomland forest near Talkeetna.Predominant trees are poplar and white spruce with considerable brush llllderstory.This forest type can easily conceal a transmission clearing. -.,",.'.'1.tUpperWellsCreek,approachingpasstoLouisCreek.Biomeisalpinetundra.III-31 II1-32 ............... I W W Moody Pass fran Yanert Fork to Moody Cree~,.which is visible in the upper left.This pass is relatively low (2900')and wide,but soils are poorly drained and subject to permafrost. ............... I W ~ Lower Moody Creek.This is a well-dissected area,covered with upland spruce-hardwood.Routing of transmission may prove diffi- cult in this stretch. LCMerMoodyCreekatconfluencewithHealyCreek(topofphoto).Unstableslopesareevident.111-35 ............ I W 0'\ Looking north from western end of Denali Highway.Typical low brush and muskeg biomes.Trees are black spruce. .AerialviewlookingwestalongDenaliHighwayandNenanaRivertoCantwell.Notethatforestsarelimitedtotheterraceslopesandleveesoftheriverchannel.III-37 ............... I Wco .".._~ .'-.. Surface view of area typical of that shown in photo above;in this case,the Nenana River is in the vicinity of the Wells Creek con- fluence.The lowland spruce-hardwood is limited to the terrace slope and river bottom. ............... I W \D Looking wes t up the Nenana River and Denali Highway.The sources of both the Nenana and Susitna Rivers are in the Alaska Range visible in the upper left.In the upper left also is the divide between these two rivers,a wide,poorly-drained area called Monahan Flat. SusitnaRiverbetweenWatanaandVeedarnsites.Heaviervegetation,inthiscaseuplandspruce-hardwoodforest,islimitedtothevalleyslopes,thevegetativebiomeontheupperplateausisgenerallymoisttundra,muskeg,andalpinetundra.III-40 .................. I ~ --' Susitna River at Vee damsite.This demonstrates the typically in- cised character of the Upper Susitna from Devil Canyon to the Tyone River.Note that heavier vegetation is limited to slopes and creek valleys. )i)isttUndranearButteLake;lookingnorthtoMmahanFlatsandAlaskaRange.ATVtracksarevisibleintheforegromd;thesetracksstart£rolltheDenaliHighway,whichcrossestheflatsinthebackgromd.111-42 ATVtracksleadingfromDenaliHighway.Thisphotoshowstypicalmoisttundravegetationwithlow-growingbrush,peatysoil,andpoordrainage.1II-43 ............... I ~ ~ Susitna River above Denali darnsite,looking west.The few spruce to be fomd are limited to the river bottom. l ~ ............ I ~ <.TI Impoundment area of Denali damsite.The Susitna here is a rneandery," aggrading river,the surrounding land is very poorly drained and underlain by fairly continuous permafrost. ............•.f:lo 0) Maclaren River,looking north to the Clearwater MOlm.tains.The fore- ground knob is part of a morainal ridge.These morainal features are reltaively well-drained,whereas the flat low-lying lands are poorly drained with shallow permafrost tables. ............... I ~ '" Looking north along the Denali Highway to the Amphitheater Mmmtains. Morainal ridges n.m across the middle of the photo.The biome along most of the eastern half of the Denali Highway is moist tlUldra. ............... I ~ ex> Uplands near Sourdough on the Richardson Highway.This is typical of the plateau bordering the Copper River lowland on the north and east. Poorly drained,it supports many lakes,the largest of them in the Lake Louise complex. .....................•.;:. \0 The Lake Louise plateau.Biomes are predominantly lowland spruce- hardwood and muskeg.These uplands are underlain by continuous permafrost. III-50 TazlinaRiverasseenfromtheGlennHighway.III-51 ............ I 01 N Tahneta Pass area between the Tazlina and Matanuska River drainages. Lakes and muskegs are indicative of poor drainage.The mOlmtains are part of the OlUgach Range. TalkeetnaMountains;GlennHighwaynmsacrossthelowerportionsofthephoto.TheMatanuskavalleyisborderedonthenorthbytheTalkeetnaRange,onthesouthbytheQlUgach.III-53 ............ I U1.;.. HCMell Glacier and the Omgach Range.The Matanuska River flCMS in an incised channel across the middle of the photo. CaribouCreekandtheTalkeetnaMountains;GlennHighwayonlowerportionofphoto.ThistributaryoftheMatanuskaRivertypifiestheincisedcharac-terofmanyriverserodingthroughglacialdebrisandloess,suchastheMatanuska,Copper,Gulkana,andupperNenanaRivers.III-55 ...............•U'1 O'l Matanuska River and Chugach Range.The Matanuska River has a braiding channel due to the high silt load from the Howell and ],latanuska Glacier,and the glacial tributaries entering from the Chugach Range. ~ ~ ~•01......, Looking north by Paxson Lake on the Richardson Highway to the Alaska Range.Paxson Lake is an important part of the fisheries of the Gulkana River. ,,:,,,';"'"'n'~~¥W"~~!",,_"ld'""""'''''''-' ---I <.TIco SUI1IIlit Lake and the Alaska Range.Stunmit Lake is drained by the Gulkana River and is just south of Isabel Pass. ............... I U'1 \0 Isabel Pass,looking north to Rainbow Ridge.The Richardson High- way,the Delta River,and the Alyeska Pipeline cross the photo at the base of Rainbow Ridge. ............... I 0'\o RainbCM Ridge,as seen from the south.The Richardson Highway crosses under the ridge fran right to left.The slope of the ridge is a series of adjoining talus cones some of which are unstable. ---I O'l.... Delta River by Black Rapids Glacier.The glacier is partially visible in the upper center of the photo.The Delta River carries considerable ,glacial silt,resulting in aggradation and braiding of the charmel. "'rif ...............•m N Alaska Range seen frcrn the north from the Richardson Highway.This is not true perspective as seen from the highway,since the photo was taken with a telephoto lens..-- ---•mw The Alaska Range seen from the Richardson Highway near Donnelly Dome, looking south.The dust is from the channel of the Delta River,which .is extremely undersized for its channel. .....'...'.,. ............... I 0\ ~ Another view of the Delta River as seen fran near Donnelly Dome. Again,the blowing dust from the channel is evident. ............... I 0\ CJ1 Alaska Range from Big Delta,taken with telephoto,In the foreground is the Del ta River channel,which near here joins the Tanana River. ---•0'\ 0'\ Fann near Delta Jtmction.Some attempt at fanning is made in the ClealWater Lake area,but agriculture is relatively tmimportant except for the lCMer Matanuska Valley area. ---I 0'1 'I Silhouetted notch on a clearing for a GVEA distribution line. Looking~theT8D8JUlRiveracrosstheconfluenceofSh_Creek.ThebraidingofcbamelscharacteristicoftheDeltaandTananaRiversisevident.III-68 TheTananaRiverfloodplain.Thisareaisextreme-lyflatandpoorlydrained.Threetypesofbiomearerepresentedinthispicture:muskeg,lowlandspruce-hardwood,andbottomlandspruce-poplar.Thedarkforestsaremainlyblackspruce.Thesinuouslighterforestiswhitespruce,aspenandbirch.Thisforesttypepreferswell-drainedsoils,andsoisfoundonoldlevee$ofexistingandextinctchannels.tll-69 )GLOSSARYAppendixIEXHIBIT1-4 GLOSSARY-EXHIBIT1-41.Brushblades,brushhogs:Devicesmountedontractorsorbulldozerswhichcutandclearbrushwithlesssoildisturbancethanthemethodsofuprootingwiththestandardbladeorshovel.2.Chipping:Methodofdisposalofclearedbrushandslashbymechanicalcuttingintosuitablysmallchips,whicharetheneitherdispersedorhauledaway.3.Climax:Astableconditionachievedbyacommunityofplantsandanimalsresultinginsuccessfuladjustmenttoitsenvironment.Thestabilityinvolvedisofalong-termnature;short-termfluctuationsaretobeexpected.Inthisway,aclimaxstageofdevelopmentcanbeconsidereddynamicallystableratherthanstatic.SeeSuccession.4.Conductor:Thepartofthetransmissionsystemwhichactuallytransmitspower.Inoverheadsystems,thisisanuninsulatedcable,generallyofaluminumandsteel,connectedtothetowersbywayofinsulators.Inunder-groundsystems,theconductorisgenerallyaluminumcableinsulatedwithoil-impregnatedpaper,oil,orplastic.Thiscableisoftenwrappedinaprotectivesheath.Inoverheadsystems,therecanbemultipleconductorsperphase.Singleconductorsarecalledsimplex;doubleconductorsarecalledduplex.Largernumbersofcablesperphasecanbeused,theresultingcombinationcalledconductorbundles.5.Corridol':Ageneralizedroute.Astripoflandofvariablewidthjoiningtwoendpoints.Inthisassessment,corridorsarenotdefinedinwidthandfinallocation.AmorespecificlinearlocationistheRoute.6.DangerTree:Anytreewhichthreatensthesafetyofatransmissionsystem.Severalfactorsdeterminedangertrees:voltageofline,heightoflineaboveground,heightoftree,growthrateoftree,anddistanceoftreetocenterline.Thesetreesmustbeperiodicallyidentifiedandremoved.7.Ecosysem:Thecomplexofacommunityanditsenvironmentfunctioningasanecologicalunitinnature.8.ElectromagneticInterference(EM1):Interferencewithradioandtelevi-sionproducedbycoronalossesfromtransmissionlines.EMlisafunctionofmanyfactors,amongthemthevoltageoftheline,theconfiguration,site,heightandageoftheconductors,andatmosphericconditions.IV-l 9.Fault:Inthetransmissionsense,aconditionofeitheropenorshortcircuitingcanbecausedbydefects,lightning,groundingorconnectingofphases,droppingofoverheadcable,orbreakininsulationinundergroundcable.Inthegeologicsense,afractureinthecrust,alongwhichdisplace-menthasoccurred.10.Free-standingTowers:Atransmissiontowerdesignneedingnosupportfromguyedcables.Thisdesigngenerallyhasfourlegs,andisusuallyofsteellatticeconstruction.SeeGuyedTower.11.GenerationSite:Anypowersite,withoutregardtomethodofgeneration.Generationsitesareoneendtotransmissionlines.Inthisassessment,thegenerationsitesarethepotentialpowersitesontheUpperSusitnaRiver.12.GuyedTower:Atransmissiontowersupportedbytwoormoreguyedcablesandpivotingononeortwopoints.Generallylighterthanfree-standingtowers,theyaremoresuitedtohelicopterconstruction.SeeFree-standingTO\1\1ers.13.Habitat:Theparticularareainwhichaplantoranimallives.Ingeneral,anyareapossessingthoseconditionsnecessarytosupportapopulationofaparticularplantoranimal.14.Herbicide:Avarietyofpesticidewhichaffectsplants.Herbicidescanbegeneralorspecificinaction,andofvariouspotenciesandduration.15.Interconnection:Theconnectionoftwoormoreindependentpowersystemswithtielines.Besidesanincreaseintotalreliability,theopportunityexistsforonesystemtosellsurpluspowertoanother,whichcanresultingreaterefficiencyofgeneration.16.LoadCenter:Apointatwhichtheloadofagivenareaisconcentrated.Forexample,theAnchorageloadcenter,asreferredtointhisassessment,coverstheloadincludedintheCEA,AML&P,HEA,SES,andMEAsystems.Theloadcenterisassumedtobethereceivingendofatransmissionline.SeeGenerationSite.17.Permafrost:PermafrostisaconditionresultingwheneversoilorrockhasbeensubjectedtoanannualaveragetemperatureoflessthanOOCformorethantwoyears.Ice-richpermafrostispermanentlyfrozensoilwithahighmoisturecontent.Permafrosttableisthelevelbeneaththesoilsurfacewhichremainsfrozenthroughsummer.IV-2 18.Right-of-way(ROW):Aright-of-wayisastripoflanddedicatedforuseofsomeutility,suchastransportationortransmission.ThelandwithinaROWissometimesaneasement,notinvolvingthepurchaseoftheland,orcanbeownedbytheutility.Theright-of-waywidthforatransmissionlineisgenerallylessthan200feetwide.Clearingwidthandright-of-waywidthshouldnotbeconfused;clearingwidth,ifclearingisneededatall,isalmostalwayslessthantheright-of-waywidth.19.Route:AdefinitelocationofaROW,asopposedtoacorridor.20.Seismic:Pertainingto,subjectto,ofthenatureof,orcausedbyanearthquake.21.Substation:Afacilityatajunctionoftransmissionlinesoratthepointofdistributiontoaloadcenter.Asubstationfunctionstoswitchpowerandraiseorlowervoltage.SeeTap.22.Succession:Aprocessbywhichacommunityofplantsandanimalsachievesastableadjustmenttoitsenvironment;asuccessionalstageisatransitionculminatinginastableclimaxstage,providingtheprocessisallowedtocontinue.However,duetonaturalandhumancauses,acommunitywilloftenneverreachaclimaxstage,thesuccessionalstagesbeingmaintainedbyfire,logging,grazing,agricultureorotherreasons.23.SystemPlan:Aplanoftransmissionfromgenerationsitetoloadcenterwhichisacombinationoftwofactors:thecorridorlocationandthevoltageandcapacityofthetransmissionline.24.Tap:Adrawingofpowerfromatransmissionline,particularlyatapointbetweenthegenerationsiteandthemainloadcenter.Eachtapwillinvolveasubstation.25.UtilityCorridors:Aconceptofconcentratinggenerallyparallelrights-of-way,eventothepointofsharingofrights-of-way.Therights-of-waycanbeforvariousutilities,suchaspipelines,railroads,transmissionlines,andhighways.26.Sedimentation:Theintroductionintoastreamorlakeofsedimentnotnormallyassociatedwiththatwaterbody.Althoughsometimescausedbynaturalagents,suchasslidesorerosiontriggeredbyfires,itismoreoftenaresultofman'sactivities,suchasloggingandfarming.IV-3