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Home My WebLink AboutAPA1364I I "' I I A LASKI\ PONER AUTHORITY I SUSIYNA HYDROELECTRIC PROJECT ••• I ~. NOTES ON STUDY STATUS FOR SUBMISSION TO FERC I I •• ,J I APRIL 1981 I I I I ACRES AMERICAN INCORPORATED 1000 Liberty Sank Building Main at Court I Buffalo, New York 14202 Telephone: (716) 853-7525 I I I I I I I I I I I I I I I I I I I I TABLE OF CONTENTS 1 -EXTRACTS FROM PROJECT OVERVIEW REPORT 2 -PROJECT SCHEDULES NOTES ON SUSITNA BASIN DEVELOPMENT SELECTION 3.1 -Introduction 3.2 -Evaluation of Susitna Basin Develcpment Plans 3.3 -Comparison of Generation Scena~ios .~ APPENDIX System Generation Plans -Backup Information and Summary Tables I EXTRACTS FROM ;PROJECT-oVERVlEW·REPORT •'.:::::; .I (j ffi •. ·. . . I .::::: I .. . -__ "' .. 1 . I I I I I I I I I I -- I I I I I I I I I ::; . " ~ . .. . ~ . .. ~ . . ' . . . .. . . 1. 'EXTRACTS FROM.PROJECT OVERVIEW'REPORT The Project Overvi·ew Report is intended to be a summary of the status of feasibility studies undertaken during 1980.. This report is reproduced on the followiRg pages. I I •• I -I I I I I • • I I I I I I I I ' . I ~~ASKA POWER AUTHORITY S\IJSITNA HYDROELECTRIC PROJECT ·PROJECT OVERVIEW - TABLE OF CONTENTS - Page l -INTRODUCTION ., ••• -. ........ ~-•••• , • • • • • • • • • .. • • • • • • • • • • • .. • • • • • • • • .. • • • • • • • .. • 1 2 -THE DECIS-ION PROCESS ............................................... ~ • .. • • • • 3 • 3 -ALASKA . POWER AUTHORITY. • • • • .. • • • • • • • • • • • • • • .. • • • • .• • • • • • • • .. • • •. • • • • • • • .. • • • 3 4 -HISTORY OF THE SUSITNA PROJECT.............................................. 4 5-ECONOMIC SCENARIOS AND PARAMETERS ..................................... . . 6 6 -MARKET AREA AND POWER DEMAND FORECASTS..................................... 7 7 -SUSITNA BASIN STUDIES..................................................... 9 7.1 -Hydro logy .......................................... ·• • • • • • .. • • • • .. • • .. • • • •. .. .• 9 7 ~ ~;;..Q C'vt-t-el Awa::.+-1• ftA !!ll.,._.-i; c_,...,...,_1..,ga• Q , .c.. = .., ; "',... '-".., Vf \6 ... vu QliU Q'=U tU .Y• ................................ * •.• .. ... ., 7.3-Sei-smic Considerations ................................. ~ •••.••.••.•• 12 7. 4 -Dam Site Se 1 ect ion •••••••••••••••.••..•• ., •• " • " .... ,. ., .. ·~.. • • • • . • • .. • .. .. 12 8 -GENERATION EXPANSION PLAN ................................ o................. .. 14 9-SUSITNA HYDROELECTRIC DEVELOPMENT ............................................ 16 10 -ENVIRONMENTAL PROGRAM.. • • .. • • • • • • • • .. • ... • • • • • • • • • • • • • • .. •. .. • • • • • • • • • • • • .. • .. • • 23 11 .. ANALYSIS OF SOCIOECONOMIC IMPACTS ........................ _, .......... "., ..... 24 12 -ECONOMIC FEASIBILITY AND NET ECONOMIC BENEFITS .................... 0 ••• ~ .. 24 13-POWER AND ENERGY MARKETING ................................................. 25 14 ... PUBLIC PARTICIPATION PROGRAM .............................................. 25 15 -LICENSING AND PERM ITT! NG PROCEDURES ................... ~ • •. • • • • • • • • • .. • • .. .. 25 · 16-FINANCIAL FEASIBILITY ANALYSIS .............................................. 26 17-SECURITY OF-PROJECT COST AND REVENUE STRUCTURES •••••••..•••••••••••••• 27 18-ORGANIZATION AND MANAGEMENT ............................................ 28 . .· . . ~ 19-IMPLICATIONS OF PROCEEDINS ........................................... o ••••• . , I I I I I I .I . I I •• I .I I I I I I I I 1 -INTRODUCTION PROJECT OVERVIEW SUSITNA HYDROELECTRIC PROJECT ·Acres American Incorporated (Acres) was comnissioned by the Alaska Power Authority {Power Authority) on December 19~ 1979, to conduct a detailed feasibility study af the Susitna Hydroelectric Project, evaluate the environmental consequences of any proposed development, and prepare a license application to be filed with the Federal Energy Regulatory Commission (FERC) in the event that the State of Alaska regards filing .such an application as being in i·ts best interests • If development ev-er takes place in the Susitna River Basin (see Figure 1 for a basin map annotated to show potential dam sites), it is likely that extensive~ costly and lengthy construction activity will occur there. Benefits of long ... term and relatively low-cost electrical energy may be possible. Yet, permanent alteration of the environmental setting in the Basin will be inevitable. The basis for a decision to proceed with the Susitna Hydroelectric Project requires that u variety of scientific, engineering 7 financial and economic disc.iplin~s be brought together. Investigations and analysis in each of these aPeas must necessarily be thorough and, further;i should be consistent with state-of-the-art techniques. Documentation of these activities tends to be voluminous as we17 as highly techni.cal in nature. The purpose of this Project Overview is to pruvide a review of all major aspects of the project and its objectives, determining in principle whether these can be met. In effect, it brings together complex issues and detailed technical results so that decision makers within the State of Alaska and interested members of the public can assess results achieved to date and determine what the future course of action should be with respect to the Susitna Hydroelectric Project • . Succeeding sections are arranged to present the framework within which the Susitna Study is conducted and the preliminary results achieved after the first full year of effort. Section 2 describes the decision process which requires two reports which the Power Authority must make to the Legislature4 The nature and the role of the Power Authority are addressed in Section 3. After a brief history of the Susitna Project is presented at Section 4, Sections 5 through 13 consider technical~ economic~ environmental and marketing aspects. An introduction to the important publ i= participation program follows at "Section 14.. Licensing and permitting is described in Section 15. Financial -matters, including financial risks, are discussed in Sections 16 and 17. Section 18 qescribes the organizational arrangements necessary for effective project implementation. A final section (19) reviews the implications of proceeding with the work after the first decision point on March 31, 1981. A detailed appendix to this overview has been prepared. It conta.ins a complete chapter to correspond to each of the sections appearing herein. Copies of the detailed appendix have been furnished to the Power Authority and to its external review panel. l - ----------- • DAM SITE 20 !!!!!!I I ~ FIGURE 1 f I I I I I I I I I I I I I I I I I I I In addition to this project overview, a second major document bears upon the March 31, 1981~ decision process. The Development Selection Report (some of which is encapsulated in Sections 7, an and 9 below) provides the detailed basis· upon which a recommendatio~ has been made by Acres to APA regarding the proposed site on which the 1981 program will focus. 2 -THE DECISIOK PROCESS Two important decision points have been designated by HCSSB 294. This legislation requires that the Power Authority, by March 30, 1981, submit a preliminary report to the Governor and to the State Legislature 11 recomnending whether work should continue on the project.~~ A second decision point, also explicitly legislated, occurs in. April 1982, when the Power Authority must submit a second report recommending whether work should continue on the Sus~tna Hydroelectric Project and other viable alternatives. It is important to note that neither of these decision points is intended to produce a commitment to construct a project. Indeed, construct ion of dams and other faci 1 ities in the river channel is not possible until or unless an FERC license is awarded. -In addition to work being accomplished by the Acres team~ several other ongoing activities bear upon the decision making process. A sepdrate ccmprehensive study of alternative means of satisfying future Railbelt energy anti load proJections will be accomplished by an independent consulting firm under contract to the State of Alaska. The Susitna project will represent one of many possible alternatives considered in that effort. Other alternax.ives im:.lude~ · but are not necessariiy limited to, thermal energy {particularly coal fired~ since Alaska is richly endowed with significant undeveloped.coal resources)~ wind, solarlt non-Susitna hydropower, and tidrll power (for which a preliminary assessment of potentittls and constraints is now underway). In addition, the Power Authorit;) has contracted with a major consult-ing firm specializing in electrical ~.transn1ission to consider an il'!tertie between Anchorage and Fairbankso This latter project may be beneficial irrespective of whether the Susitna River Basin is ever developed, but the results of the study will necessarily be important to the analysis of transmission facilities required for a Susitna Project. 3 -ALASKA POWER AuTHORITY The Power Authority was created in 1976, by action of the State Legislature, as an autonomous branch of the Alaska Department of Comnerce and Economic Development. The basic mission of this agency is to develop energy generation projects (excluding nuclear) in an economical manner. Governed by a Board of Directors, the Power Authori.ty t5nploys an Executive Director and a staff which carry out day-to-day activities. Directors of Engineering 9 Ftnance 7 and Public Participation assist the Executive Director in performing his functions. The 3 I I I I I I •• I I • I I I I I I I I I I .., staff also includes a full-time Native Inspector, an Administrative Assistant, and Project Engineers an(f other suppor"cing persorme 1. An organization chart is provi_ded as Figure 2. As of the end of 1980, the Power Authority was engaged in six reconnaissance studies~ four design projects, two 1icense application ~ubmittals, five construction projects, and eleven.feasibility studies (Susitna being the largest). Procedures adopted by the Power Authority for the Susitna study include the formation of a Steering Committee to ensure that interested State and Federal Agencies are kept informed throughout the course of the work and to provide a vehicle whereby their concerns and recommendations can be taken into account as the study progresses. Heavy emphasis is also placed on the opinions and concerns of the public, and an aggressive Public Participation Pragram is conducted • 4 -HISTORY OF THE SUSITNA PROJECT Because of its strategic locatton between Anchorage and Fairbanks, the Susitna River has long been regarded as worthy of consideration for development of its hydroelectric potential. Shortly after World War Il, the U.S. Bureau of . . Reclamation ·(uSSR} did an initial Territory-wide reconnaissance., noting the vast hydroelectric potential in Alaska, and placing particular emphasis upon the perceived advantages of a Su~itna Hydroelectric Project. The U.S. Department of Interior (of which USBR was a part) undertook geotechnical and other field investigations and, in 1961, proposed authorization af a two-dam system on thP. Sus i tna River. This report was 1 ater updated in 197 4 by the Alaska Power Administration (also then a part of DOI) and the desirability of proceeding with the project was reaffirmed. The ~.S. Army Corps of Engineers_ (COE) was also active in hydropower investigations in Alaska in the 1950's and 1960's. Focusing its initial attention on the Rampart Project on the Yukon Rive~, the COE found by the early 1970• s that the environmental consequences and 1 imited market for Rampart power militated against its development. The 1973 energy crisis rekindled interest in hydropower deve 1 opment ~md the COE was comni ss i oned by the U.S. Congress in 197 4 to conduct a pre-feasibility study of the Susitna Project. The results of this effort were first referred to the Office of Management and Budget in 1976 .. Further geotechnical work followed and a new COE report was issued in 1979. The State of Alaska itself conmissioned an assess,nent of the Susitna Project by the Henry J. Kaiser Company in 1974. Although differences appeared in the various proposed development schemest a11 of the foregoing organizations were unanimous in reconmending that Susitna hydroelectric potential be devel~ped. After thE Power Authority was formed, the State of Alaska elected to proceed independently with a major feasibility study. A detailed Plan of Study was qistributed widely in February 1980. Subsequent modifications~ some of which 4 -.. --- --· - - - - --; ----' ---\ NATIVE INSPECTOR DIRECTOR OF FINANCE FINANCIAL STAFF . BOARD OF DIRECTORS EXECUTIVE DIRECTOR '---'·~---v---- DIRECTOR OF ENGINEERING ENGINEERING ·STAFF DIRECTOR OF PUBLIC PARTICIPATION PUBLIC PARTICIPATION STAFF ALASKA POWER AUTHORITY ORGANIZATION ADMINISTRATIVE ASSISTANT 'OFFICE CLERICAL . FIGURE 2 , I I I I I I I I I • I I I I I ·~ I I I I were occasioned by statements of public concerns, were directed by the Power Authority itself as well as by the State Legislature.. Salient fea-:ures of the Plan as it now stands are these: -The development of electrical ener~y demand forecasts has been accomplished independently by the Institute fG· ::'.Jcial and Economic Research (ISER}, University of Alaska. -The study of alternatives~ as noted earlier, is being accomplished separately from the Susitna Study. -The Public Participation Progr~ is handled by the Power Authority itself rather than by Acres as originally proposad. -Major tasks have been designated to handle each facet of the work. These tasks includa such activities as load forecasting, surveys and field support activities, hydrology, seismic studies, geotechnical investigations, design studies. environmental studies, transmission studies, development of cost estimates and schedules, licensing activities., finance and marketing studies, public participation and administration. Each task is further subdivided into subtasks so that more than 150 separately defined study activities wi11 be completed prior to submitting a license application to FERC in June 1982--if affirmative decisions are made at the March 1981 and April 1982 milestones .. 5 • ECONOMIC SCENARIOS AND PARAMETERS The vi abi 1 ity of a Susitna Hydroelectric Project depends to a great extent on the costs of generating electrical energy by alternative means* Thus, for example, if the cost of natural gas from the Cook Inlet area rises more rapidly in future years than the general inflation rate, it is likely that utilities will turn to sources other than gas for future expansion of generating systems. Hydropower might then enjoy a more fa,vorable position. Conversely, if certain fuel prices rise less rapidly than the general inflation rate, hydropower may not necessarily represent an economical choice for future system expansion. Other factors. will also affect Susitna viability. For example, demographic variables, energy demand·, unit labor costs, other comnodity prices, overall price inflation, and interest and discount rates must be projected. An economic analysis was conducted so that, to the extent possible, logical and non-contradicto.ry views of the world would emerge. No matter how carefully such an analysis is conducted, however, it is necessarily imprecise simply because it depends upon the prediction of an uncertain futu~e. Thus a range of values bounding each selected parameter was selected as the basis for testing the sensitivity of a Susitna Project to possible deviations from most likely values. Forecasts of world energy balances indicate a worldwide shortfall in oil supplia~ within ten years. .By 1990, the United States is expected to be i«~ort i ng 16 percent of . its energy needs (an improvement .over the 22 percent .leV'ei of 1978). It is likely that fossil fuel prices in the U.S. will continue 6 I I I I I I I I I I I I I I I -· I I I to esc a 1 ate at rates on the order of two to four percent abov.e the over a 11 inflatiori rate .. Gas and oil price escalation will be at the upper end of this range~ with coal escalation somewhat less. Fuel prices in Alaska will generally reflect market prices in the United States and abroad, less the cost of-getting Alaskan fuels to the market. Insofar as prospects for economic growth in Alaska are concerned, three different economic scenarios were developed by ISER. The lowest assumes only modest population and employment growths at just over two percent. The highest forecasts these values at closer to four percento If the volume of State government expenditures varies significantly from current levels, these ranges will be broadened. · Opportunity values and escalafion rates in Alaska in dollars per million Btu (where a Btu is a unit of energy) were selected as follows: Nc,tural Gas Coal Oil $/Million Btu Opportunity Value ( 19~l2.._.Q£·11 ars } $2 .• 00 $1.15 $4.00 1980 -2005 Escalation in Excess of Normal Inflation 3.98~ 2.93% ' 3 .. 58% Exclusive of inflation, a real interest and discount rate of three percent was adopted as most likely. 6 -MARKET AREA AND POWER DEMAND FORECASTS The forecasting methodology employed by ISER relied upon an end-use model rather than on the extrapolation of past trends as the basis for projecting future demand. As its name implies, an end-u-se model considers electricity consumption in terms of end use in various sectors of_the economy. In the residential sector, for example, electricity consumption is largely attributed to space heating., refrigerators 9 water heaterss lights, cooking ranges, and certain other major appliances. Knowledge of the number, type, and expected changes in households can lead to assessment of future residential demand for electricity. The annual growth in total Railbelt Utility Sales ranged from 2.8 percent to 6-.1 percent in the lowest and highest economic growth scenarios respectively. These values may be compared to an actual average annual rate of 15.2 percent for the period 1940 to 1978 and to 11.7 percent for the 1970's. Figure 3 illustrates alternate demand forecasts. Peak load forecasts were derived by applying historical load patterns by sector to the ISER demand forecasts. Peak loads are expected to increase at approximately the same percentage as total electrical energy demand for each of the selected ranges. 7 I I I I I I I I I I -0 - I I I I I I I I I 18 17 16 1!'5 14 13 12 -~ ~~~ 2 ~ JO -en ..... 9 ....J ~ (I) 8 ,_ r-7 -(,.) = ~ 6 0 LIJ ..J e ••• 11611 4 3 2 I 0 1980 LEGEM) HE.S .. GH a Hfetf ECCIIGIINC GROWTH + HIGH GOVERNIIEHT EXPENDITURE HES·GU s Hf8H £COM:IMtC GROWTH +MODERATE GOVERNMENT EXPEMlrrUR£ • II£S·GM = Ma0ERAT!: ~NOMIC GROWTH + MODERATE GOVERNMENT f!XPENDmJRE L.ES • GM = LOW ECONoMIC GROWTH + MODERATE GOVERNMEH"r EXPENOITUR£ L.ES·GL: l..OW ECONOMIC GROWTH + L.OW GCVERHMENT EXPEMOITUitE 1990 i995 2000 200S 2010 YEAR ALTERNATIVE UTI LlT~f SALES FORECASTS ' FIGURE 3 I I I I I I I I I I I I I I. I J, I ,. ·I lf more extreme measures are taken {probably through legislative action rather than voluntary efforts)~ some potential for further energy conservation and for· load management could lead,to a lower forecast than the lowest noted above. An extreme low forecast was selected for sensitivity tests in later analysis. 7 -SUSITNA BASIN STUDIES During the past year, a massive field data collection effort got underway .. Operating primarily out of a base camp constructed at the Watana site, investigative teams were engaged in environmental data collection, survey activities, geotechnical exploration, geological mapping, seismological investigations and hydrological and cl imatologica 1 data collection. 7.1 -Hydrology Gaging stations and weather monitoring stations were added to the network which had been installed and operated by State and Federal agencies in prior years. Information collected at new stations has been useful in correlating data obtained there with longer term records at older stations. The Susitna River exhibits two distinct seasons of flow. Hi<gh spring and sunmer flows (produced by snow and glacial melt and heavy rainfa.ll) contr·i bute about 90 percent of the a:nnua 1 tot a 1 between May and October. The winter flow is relatively low and most of the smaller tribut·aries do not sustain flow during the coldest months. Figure 4 illustrates flow data at Gold Creek. Based on data collected to date, initial determinations have been made of probable maximum floods (the theoretical maximum which could be produced given the physical na.ture of the Susitna Basin) and design floods (1 in 10,000 year events) wh;~n must be safely passed by dams that might be constructed on the Susitna. In addition, of course, hydrological data was used to estimate probable average and firm energy outputs from potential developments. It is worth noting that less than.20 percent of the total Susitna River flow into Cook Inlet is contributed by the Susitna and its tributaries above Gold Creek. Significant contributions downstream occur from the Chulitna, Talkeetna, and Yentna Rivers. Figure 5 displays percentage composition of total flow by major tributary. Ice formation, both in potential reservoirs and downstream of possible dams, continues to be studied, for it must be dealt with during construction and its impacts during operation must be determined. 7.2-Site Explor~tion and Geology The Susitna Basin has a complex geology. Studies have been made of the region in general and detailed information was collected at particular dam sites and potential sites {borrow areas) for materials with which to . construct the project. Three core holes per site were drilled at Watana and Devil Canyon during 1980; 15 auger holes were placed.to explore borrow 9 m.ooo a ~ 40,000 u w (/) 0: ~ t-30,000 ~ u. 0 -m ::l 9 ' ~ 20,000 ~ ~ w It: 1- U) 10,000 LEGEND JAN FEB MAR APR MAY JU.N JUL AUG SEP OCT NOV DEC SEASONAL DISTRIBUTIONS OF FLOW IN THE SUSITNA RIVER AT GOLD CREEK WETTEST YEAR 862 AVERAGE YEAR DR lEST YEAR leti$ FIGURE.4 .. I. I. I I I I I •• I I I I I I I I ·I. I I SUSITNA RIVER DEVIL WiltaNA CAN'YON SITE SJTE COOK INLET GoLD CREEK PARKS HIGHWlY BRIDGE GAGING STATION" AVERAGE ANNUAL FLOW DISTRIBUT10N WITHIN THE SUSITNA RIVER BASIN 11 FIGURE 5 ' ' I I I •• I I I I I I I I I I I I. I I I areas; and approximately 28,000 feet of seismic lines were rune While g~eotechnical data gathered to date has generally confirmed the suitability of Watana and Devil Canyon sites for dam construction, a geotechnical ptrogram has been designed for 1981 further to define the nature of the sites and to answer questions about certain subsurface features which could influence the type and precise location of dams and other project features • 7.3 -Seismic Considerations The Upper Susitna River Basin is a seismically active area. Thus, a major seismic program was started in 1980. A microseismic network of 10 stations was installed and operated to collect microearthquake data for the region. Potentfal faults and lineaments were identified by air and ground reconnaissance, satellite imagery, airborne remote sensing and aerial photography.. A detailed screening of all identified features resulted in the selection of 13 for further study in 1981. On the basis of the current state of knowledge, the Denali Fault (65 km north of the sites) and the Benioff Zone (60 km underground below the sites) are regarded as the most likely severe seismic hazards. Figure 6 illustrates the seismic setting. Initial estimates of maximum credible earthquakes from these features suggest a: m&gnitude of 8 .. 5 on the Richter Scale. Dam design to safely withstand ground accelerations associated with such an event is within the-state of the art. A study of Reservoir Induced Seismicity (RIS) was also initiated in 1980. RIS may be caused by the increased weight of water in a new reservoir or by lubrication and hydraulic action upon highly· stressed rock. Based on evidence gathered to date~ an RIS e·vent wi 11 not exceed the maximum credi b 1 e earthquake that could be associated with a fault.. Thus, RIS is not likely to affect the determination of design earthquakes. 7 .. 4 -Dam Site Selection A total of 12 dam sites was considered in the site selection process (See Figure 1}. By combination of two or more· sites as a system, the total basin potential can be developed in a variety of ways. A detailed screening of individual sites and logical combinations of sites permitted elimination of those whose relative costs were high or whose obvious environmental disadvantages. were large. ·Preliminary layouts were developed for each of the most promising sites. Candidates selected for further analysis in generation planning and for mor~ thorough environmental consideration ,~~eluded (1) the Watana and Devil. Canyon dam sites (the combination found most suitable by the COE in the 1976 and 1979 studies); (.2) High Devil Canyon (favored by Kaiser in 1974) and Vee; and (3) a combination of a Watana dam, a rel ative1y low re-regulation dam midway between Watana and Oev i 1 Canyon and a tunne 1 from the low dam with a downstream portal near Devil Canyon. Within these groups, further 12 . . ---- A LASKA DEVIL ... . ·~ -------,· RANGE -~· -j 1,~ '-"~ """ ---' - TALKEETNA T E R R A ,N E 'Jt,~:. ""'- MOUNTAINS r ~~ ~ U =:...,..;------• GLENNALLEN D '"' ...... -=----oq;--....... ' ........... CHUGACH MOUNTAINS MOUNTAINS SUSITNA PROJECT SEISMIC SETTING . . ~ ~ -.• i -' ' FIGURE 6 I I I I I I I I I I I I I,· I I I I a· . ' I t va~iations were. studied in terms of alternative dam types and heights and possible schedule variations. 8 -GENERATION EXPANSION PLAN The current generation system in the Railbelt is primarily based upon thermal power. Natural gas is used heavily in the Anchorage ar-ea, oil fired units predominate in Fairbanks, and several small coal~fired plants operate at Healy a..11d in the Fairbanks area.. Hydroelectric energy,-primarily from the Eklutna project, also contributes a small portion of the current Railbelt electric generation. The present system will evolve in future years as demand increases and as old units reach the end of their useful· lives. Regardless of whether or not a Susitna Project is ever developed, new system additions will be needed. For planning purposes, it was assumed· that the Bradley Lake Project (now being pursued by the COE) and certain thermal units now under construction.wiii be on line by the early 1990's. New capacity is necessary after 1992., but the amount and type to be added in any particular year will vary as a function of the demand· and peak load forecasts. A generation planning exercise was conducted to determine how each of the potential Susitna developments might fit into future Rai1belt generation . systems. The General Electric Optimized Generation Program (OGP) was the primary tool used for this purpose. In addition to Susitna and present and planned capacity~ major alternatives including coal-fired plants:. gas turbines, gas-fired combined-cycl~ plants, and the ten best non-Susitna hydroelectric sites were considered as candidates for future expansion.. On an economic basis, it was. determined that Watana/Devi 1 Canyon, High Oevi 1 Canyon/Vee, and Watana/Tunnel all produced total generation system present worth costs which were 1ess ·than the least cost system without Susitna. Of the total sets considered, the Watana-Oevi 1 Canyon combination was favored economically. In the case of the most likely ISER .forecast, the most appropriate time to bring-an initial 400 MW Watana project on line was found to be 1993. Figure 7 provides a system energy comparison for the mid-load forecast for a base case thermal system and for a Watana/Oevil Canyon development (Susitna 3AE). Detailed generation planning analysis of the most promising development plans indicates that the Watana-Devil Canyon development plan is the pre- ferred option. The studies to date clearly show that the tunnel option is higher in cost and provides less energy, but it may offer certain environ- mental advantages, in that approximately 15 miles of the Susitna River, including a part of Devil Canyon itself, would not be inundated. However, the environmental benefit would not at this time appear to be justified by the substantial additional cost and energy loss o.J this alternative. Preliminary studies of tidal power potential have conmenced. Tidal power development, if found feasible, would necessarily lag the earliest possible Susitna development simply because time-consuming detailed environmental and engineering investigations would have to be undertaken before a license application could be submitted to the FERC. Tidal power characteristics and 14 Revised April 16, 1981 I •• I I I I 'I I I I I .. 1 I ••• I •• I .J I I ENERGY (GWH) ENERGY {GWH) , JO,ooo.---....,..--..,.----r----.....,..--..,....---,~-...... THERMAL 10,00() ,..,_-.....,..--...,._--r----.,..--..,.---..,--....., ATURAL GAS 2 '000 1"'-------t---TURBINES SUSITNA 3AE SYSTEM ENERGY COMPARISON MID LOAD FORECAST 15 FIGURE 7 I 1: I I ·- I I I I .. ,I I I t I I I I I I ;I costs will be available by mid-1981 as an input to the independently cond~cted Railbelt Alternatives Study. For generation planning purposes in the Su~1tna study, it has been assumed that t~dal power.generation is not available 1n 1993 when Watana could be brought on ltne economtcally. A series of sensitivity tests was run to determine how variations in key parameters wou 1 d affect the choice of favored p 1 an s • These tests genera 11 Y . demonstrated that.the Watana-Devil Canyon develoPment is the most cost effect1ve alternative among Susitna Basin plans through a reasonable range of fuel costs, fuel escalation rates, real interest rates, and the like. 9 SUSITNA HYDROELECTRIC DEVELOPMENT The development selection activities are not yet complete, but the extensive study of the alternative dam and tunnel schemes for developing the power potential of the Susitna Basin indicate that High Devil Canyon and Watana are the two largest and most economic energy producers in the basin.· • Other sites such as Devil Canyon, Olson and Gold Creek are competitive provided they have additional upstream streamflow regulation. Sites such as Vee and Susitna III are medium energy producers although somewhat more costly than the larqer dam sites. Sites such as Oenali, Maclaren and Tyone are expensive compared to other sites. · A comparison of the Devil Canyon site to the best tunnel alte~ative shows that the tunnel scheme is more expensive. The environmental impacts of the various sites are a function of their location along the river. ·· Under existin~ conditions, salmon migrate as far as Devil Canyon, utilizing Portage Creek and Indian Rfver for spawning. The develo~ent of a~ dam downstream of Portage Creek would result in a loss of saimon habit<it. The necessary FERC license and permits for such development would probably be di~icult to acquire. Be~een Devil Ca~on and ~tan~. the concerns asso- ciated With development relate mainly to the inundation of Devil Canyon, which is considered a unique scenic and white water reach of the river, and has dam safety aspects associated with the occurrence of major geological faults. In addition, the Nelchina caribou herd has a general migration crossing in the area of Fog Creek:--· In the next upstream reach, between Watana and Vee, there are concerns which relate·to th~ loss of some moose habitat in the Watana Creek area and the inundation of sections of Deadman and Lokina Creeks. Other aspects inGlude the ef~ct on caribou crossing in the Jay Creek area, and the potential for extensive reservoir Shoreline erosion and dam safety because of the possibility of geological faults. Between Vee and Maclaren, inundation of moose winter range, waterfowl breeding areas, the scenic Vee Ca~on and the downstream portions of the Oshetna and Tyone Rivers are a 11 potentia 1 envi ronmenta 1 impacts. In addition, caribou crossing occurs in the area of the Oshetna River. The area surrounding this section of the river is relatively inaccessible and Revi.sed April 16, 1981 16 I I I I •• I •• I I I ·- 1 I I • - I I. development waul~ open large ar~as to hunters. The segment between Maclaren and Denali, appears to be more sensitive than the area downstream of Vee. Inundation could affect grizzly bear denning areas, moose habitat, waterfowl breeding areas and moist alPine tundra vegetatio~. Improved access would open wilderness areas to hunters. The area upstream of Denali is similar to t~e reach immediately downstream with the exception of grizzly bear . denning areas. Human access to this area would not impact to the same extent that it would downstream. However, due to the proximity to the Denali highway, the inflow of peop:Je .could be greater • Detaile~ generation planning analysis of the most promising development plans indicates that the Watana-Devil Canyon development plan is the pre- ferred option. The studies to date clearly show that the tunnel option is higher in cost and provides ~ess energy, but it may offer certain environ- mental advantages, in that approximately 15 miles of the Susitna Rive~, including a part of Devil Canyon itself, would not be inundated. However, ·the ·environmental benefit would not at this time appear to be justified by the substantial additional cost and energy loss of this alternative. It is considered essential that the continuation of studies in the Susitna Basin and, if appropriate, submission of a license application should be based on a preferred total Basin development concept. Thus, for the pu~ poses of this report, it will be assumed that the Watana-Devil Canyon plan is the selected development. The most appropriate plan of Watana-Devil Canyon development involves con- structing the full height dam at Watana with a minimum installed capacity of 400 M~J initially. The second stage involves adding an additional 400 NW capacity at the Watana site. The third major stage involves constructing the Devil Canyon dam and installing a minimum of 400 MW at that site. it should be stressed that these. installed capacities are still approximate and subject t-~--~~_fineEl_ent duri~_g _,th~--_1~81_ ~t~d~~~-- 17 Revised April 16, 1981 I I -I I I I I I I I I I I I 1: - I I I I Conceotua1 Design -_, .. -m '* The engineering layouts described are also preliminary and a considerable amount of additiopal study is currently underway to complete many of the details associated with these developments. In particular, further studies are being undertaken to firm up the general arrangement of the two dam· projects; i.e.; to determine the exact location of the dams, the dam types, the number and location cf spillways; diversion and power tunnels and ~ powerhouses. A 1 so, the exact dam heights wi 11 be _determined fron:t more detailed economic studies and additional studies of reservoir operation will be undertaken to detennine optimum operating policies. Throughout 1981 the environmental studies will be continued and the required reservoir operational constraints and necessary mitigation measures will be determined in more detail and incorporated in the d~sign of the project. The river and ice field surveys and computer model studies also will continue with the results incorporated into the engineering studies .. Watana -The conceptual design involves a fill type dam incorporating a central core of impervious material. Properly graded filters are locat~d both upstream and downstream of the core, supported by shells comprised of compacted, quarried rockfill and/or gravels and cobbles. At this stage it is assumed that foundations will be excavated to bedrock beneat-h t-he entire dam and to sound rock beneath the core and filters. The bulk of the rockfill material will be taken from quarry areas located on the left abutment although some will be recovered from excavations for the various structures. Gravels and cobbles and filter materials will be recovered from the exca- vated riverbed borrow areas and processed as necessary.. Core material will be taken from borrow. The extent to which river gravels and cobbles can be utilized in the dam shells will be investigated from both technical and economic considerations in 1981. The overall maximum height of the dam is approximately 840 feet above existing rock level. Allowance has been made for static and dynamic settlement, wave runup and freeboard, and potential deformation under seismic shaking. Upstream and downstream slopes average 1:2.75 and 1:2~ respectively, and crest width is 80 feet. Shafts and ga11eries will be provided within the rock foundations and abutments for grouting and pressure relief drains. 18 Revised April 16, 1981 I I I I I I I I I I I I I I I ·~ I I Construction of an alternative concrete arch dam at Watana appears to be technically feasible but greater in cost. This option will be investigated further in 1981, but at this t"ime, a fill dam appears to be the·most suit--- able at this site •. Devil Canyon - A thin concrete arch dam, similar to that proposed by the U. S. Bureau of Reclamation (USSR), with a central integral spillway, is currently being analyzed for gravity, hydrostatic, temperature and seismic loadings .. The preliminary geometry for a two-center arch dam designed around the asymetric shape of the valley has been laid out, and stress analysis under gravity, hydrostatic and temperature loadings is proceeding. Vertical sections through the center of the dam take the form o-f a cupola with upstream and downstream faces fanned by simple vertical curves. The foundation at the center is somewhat thicker than proposed by the USSR with a general increase in area occuring at the more highly stres~ed sections .. The overall maximum height of the dam is approximately 625 feet above existing rock level, with a crest width of 20 feet. As currently conceived, the power facilities including the power intake structure, will be kept separate from the dam. Shafts and galleries will be provided outside the dam to facilitate grouting and drainage. Studies are currently underway to confirm the technical feasibility of constructing the thin arch dam and to evaluate in more detail the costs associated \>lith this type of concrete dam. Evaluation of alternative rockfill and concrete dams at this site is also being undertaken. Spillways The reservoirs at Devil Canyon and Watana wi11 be operated in accordance with nrule curves" defining nonnal operating water surface levels over a given period. These levels are contained by an envelope of extreme upper and lower surface elevations for nonnal operating conditions. If the reserv·oir level rises above the maximum nonnal operating level and the excess reservoir inflows cannot be absorbed by the power facilities, this excess flow must be released from the reservoir and discharged downstream. Spillways are provided at both sites to acconmodate these releases. The spillways may consist of one or more facilities each combining a gated contra 1 or a simp 1 e overflow structure, a discharge chute and some means .of dissipating the energy of the released water downstream of the dam. The combined facilities at each site are designed to contain reservoir levels below an allowable surcharge level for floods corresponding to a frequency of occurrence of 1 in 10,000 years. These flows will be discharged with no significant damage at the site. The discharge capacity of the structures also will be checked to ensure their ability to pass flows corresponding to the probable maximum flood (the maximum flood that may occur from a coinci- dence of extremes of all influencing factors such as precipitation, temperature and snowpack) without overtopping the dam crest. 19 Revised April 16, 1981 I I I ·t ·I I I I I I I I I I I I I I I At present, spillways have been examined as part of the concept of comparing various sites from an economic and energy standpoint and selecting certain sites for further study. To s.implify this comparison, a common fonn of spillway has been utilized which will be viable at all sites, but may not represent the most economic arrangement at any one particular site. During 1981, comparisons of various .types of spillways at the selected sttes will be made before a particular type is decided upon. Consideration is also being given to separate emergency spillways to handle extreme floods in excess of the 1 in 10,000 year or other selected design floods. Watana -At its upstream end, the spillway consists of a concrete gravity control structure with five water passages, incorporating ogee-crt~sted weirs and vertical lift gates. Downstream of the control structure is an inclfned open chute excavated in rock. The chute is lined with concrete and runs to an intermediate stilling basin where the energy at that point is dissipated in the form of a hydraulic jump. An additional 1ined chute continues to a downstream stilling ba·sin situated close to river level .. Possibly more economical spillway systems such as one or more single-chute flip-bucket and plunge-pool arrangements, or a ·combination of single-chute flip-bucket and stilling basins are currently being studied together with a separate emergency spnlway with a breachable fuse plug. Devil Canyo~ -At Devil Canyon a similar system to Watana has been located on the right abutment. It is envisaged that future studies will consider a spiilway of restricted capacity discharging through openings below-the dam crest 'IJith near vertical discharge into a plunge. pool~ in combination \'y,th one or more chutes and flip-buckets discharging into a separate downstream plunge pool. Alternatively, concrete lined tunnels and flips also dis- charging into a plunge pool, will be evaluated as well as a separate emergency spillway with a breachable fuse plug. Spillways may be situated on either or both of the abutments. An alternative dam design in which it wil1 be possible to discharge over the dam crest via a chute located on the downstream face into a lined stilling basin, is also being evaluated. Power Generating Facilities and Equipment Far the preliminary planning purposes, a similar arrangement of the power facilities has been utilized at all sites, including Watana and Devil Canyon. The system consists of an upstream approach ·channel and intake structure discharging into concrete-lined penstocks dropping to an under- ground powerhouse complex. Concrete-lined tailrace tunnels lead from the powerhouse to the river located downstream of the toe of the dam. The intake is a concrete structure founded in a rock cut and situated at the end of the approach channel. Provision is made for drawing off water at different levels within the reservoir in order to control the temperature of \'4ater released downstream. The present scheme allows for separate \'later intakes at three levels. Separate ~enstocks are provided for each turbine/ generator unit. These are inclined at 55 degrees with stee1-lined sections · 20 Revised I I I I I ... I I I I I I I ,. I I I l I I irrmediately upstream of individual turbines which are located in an under- ground powerhouse. The turbine/generator units, service bay~ workshop, switchgear room and some offices are located within the main powerhouse cavern. The turbines and generators are serviced by overhead cranes running the length of the powerhouse cavern including the service bay area. A separate transformer gallery is located upstream of the powerhouse cavern and a draft tube gate gallery just downstream of the powerhouse cavern with gates operating in vertical shafts descending to the four draft--tube tunnels. Isolated phase bus ducts located in separate inclined ga11eries connect each generator to a separate transformer. Power cables exit via vertical shafts to the switchyard at the surface. Vehicle access to the caverns is via unlined tunnels with additional personnel access provided by an elevator shaft to the surface. The control room and administration offices are housed in a separate building at the surface adjacent to the switchyard. The draft tube tunnels terminate in a common manifold. Two tailrace tunnels exit from the manifold and terminate in outlet structures located at the river downstream of the dam. These downstream tunnels are concrete-lined~ and provision is made to seal aff the tunnels for maintenance by inserting stop logs at their outlets. Watana -The power facilities described are present1y assumed to be w~thin the left abutment and are based upon 4 -200 ~1W turb-ine/generator units. However, it is possible that the rock quality and orientation of the jointing in this abutment will prevent the economical excav.ation of the long power caverns. klternatively, relocation to the right abutment or a surface powerhouse on either abutment could be utilized. These alternatives will be examined and the most suitable system selectedv Devil Canyon - A similar layout to that at Watana is presently assumed at Devil Canyon based upon 2 X 200 MW turbine/generator units and located within the right abutment_, with the intake located upstream of the dam. Access Roads A, study is currently underway to determine the most desirable location for an access route and the most economical transportation mQdes. R&M Con- sultants are conducting this work as a subcontractor to Acres. Three general corridors have been selected· to provide access to potential dam sites. These include a corridor located to the North and another to the south of the Susitna River linking each site either to Highway 3 near Hurricane, or the railroad near Gold Creek (alternatives 1 and 2) or road access from the Denali Highway to the east of the project sites (alterna- tive 3). Using design criteria generally conforming to primary highway design several feasible alignments within the selected corridors were ske.tched on contour maps. From these the route within each corridor showing the most advantageous grade, alignment and length characteristics were selected. 21 Revised I .,, .. J I •• I I I I I I .. I I ' I •• I I I These routes allow consideration of a number of transportation alternative plans including allowance for staged upgrading of the road and utilizing rail transporation segments. The environmental considerations of each route as well as land ownership constraints are currently being addressed, in addition to transportation economics. In March, 1981, a series of public workshops will be held to gain public input to the route selection process. It is anticipated that a final decision on the selected route will take place during 1981, fol- lowing which further engineering and field studies will be undertaken for the selected route. f1:!tigating Measures In developing the detailed project designs a range of mitigating measures required to minimize the impact on the environment will be incorporated. This is achieved by involving the environmental studies coordinator as a member of the engineering design team. This procedure ensures constant interaction between the engineers and envir-onmentalists and facilitates the identification and design of all necessary mitigation measures. Th.ere are two basic types of mitigation measures that are being developed: Those which are incorporated in the project design and those which are included in t~e reservoir operating rules. These are briefly discussed below. Design Features -The two major design features currently incorporated include multi-level power intake structures to allow some temperature control of released water and provision of a downstream re-regulation dam to assist in dampi119 the downstream discharge and water level fluctuations induced by power peaking operations at the dam. During the 1981 studies these two features \vi 11 be designed in more detail and other features incorporated as necessary. Of particular importance will be the design of the spillways to eliminate or minimize the impact of increased nitrogen in the downstream river reaches. · Consideration will also be given to developing mitigation meaures to limit the impact on the environment during the project construction period. The access roads, transmission lines and construction and permanent camp facilities will also be designed to incorporate mitigation measures as requirede Operating Rules -Limitations on seasonal and daily reservoir level drawdown, as well as on downstream minimum flow conditions have been imposed in plan formulation studies. During 1981, more detailed studies will be undertaken to refine these current constraints and to look at detailed of)erationa1 requirements to adequately control downstream water level fluctuations} water temperature and sediment concentration. 22 Revised I I I I I I I ~.· I ..... .;. I' j I I I """" I I '!" a I I 10 -ENVIRONMENTAL PROGRAM A major environmeotal investigation program got underway in 1980. In addition to necessary exhaustive field data CQll~ction, effort was devoted in particular to two other major components: (1) addresstng major environmental concerns including those expressed by government agencies (at Federal, Statej and local level) and the general public, and (2) envirrJnmental participation in the design process with a view toward avoiding or minimizing impacts by making design decisions which account for environmental concerns-from the start .. The environmental studies are divided into nine specific study components: -Fisheries -Wildlife -Land Use -Archaeological (Cultural Resources) -Recreation -Plant Ecology -Corridor Selection -Socioeconomic (See paragraph 11 below) -Management and Coordination At least one more year of data must be collected in each area before detailed impact statements can be prepared and proposals developed as appropriate for mitigative measures. Even so, no evidence has been discovered to date to indicate environmental impacts which are so severe as to conclusively ru}e out the possibility of developing the Susitna River for hydroelectric power production. 23 ' .J· '· I I '-' I I. I I I ·~ 'I I I I I' ' I I I Certain environmental impacts on fisheries experienced at other major hydroelectric projects will be absent from or less severe at the Susitna Pr.oject if it is ever· constructed. These. include: (a) No direetulockage of fish migration or escape will result from the dam itself. (b) No significant river di~ersions resulting in low flows in the diverted river· will occur for the Watana-Devil Canyon combination. (c) Regulation is being factored into design to eliminate significar.-• daily fluctuations in flow. (d) Nitrogen entrainment will not be increased by numerous sequential reservoirs such as are found on the Columbia River. In addition, design studi.es will incorporate the latest available technology to reduce the occurrence of such phenomena. 11-ANALYSIS OF SOCIOECONOMICIMPACTS A major socioeconomic study program was )aunched in 1980 with the objectives of describing existing socioeconomic conditions, forecasting future conditions if no Susitna Project is built, and determining which conditions are most likely to be impacted. by a.susitna development. Major efforts have been devoted to development of socioeconomic profiles during 1980.. The 1981 work will focus upon preliminary assessments of impacts which implementation of the recommended development plan could cause. 12 -ECONOMIC FEASIBILITY AND NET ECONOMIC BENEFITS The analysis of the net economic benefits of the reconmended development plan is being developed within the frama:c;-~ of traditional methodology. The general procedure cons·iders the total costs associated with the project (construction, operation, maintenance, transmission, etc.). Benefits are the avoided costs of providing the equivctlent power and energy from the next best alternative generating ~ource. J\ preliminary life-cycle cost analysis has been conducted for the recon111ended development plan as well as for other alternatives surviving the initial site screening process.. This economic analysis assumed a three percent discount rate in real terms {i.e .• , the cost of money is assumed to be three percent higher than actual inflation rates during the planning period). In 1980 dollar.s, the present value costs of the recommended hydroelectr-ic development {operated in the Railbelt System during a 60 year period for economic analysis) were less than the costs of the best thermal generation alternative. 0 .. 24 .. I ,. ·a I I -·· I I .... I I. ' ···' I I I I I ' I I I More precise values for life .. cycle net benefits will be determined as cost estimates. are developed in detai 1 for the optimized development pian in 1981. 13 -POWER AND ENERGY MARKETING Whereas it can be shown that the Sus itna Htdroe 1ectric Project would be economicaJ in the long term~ it is nonetheless true that the relatively hign capital cost of a major hydroelectric power development can lead to difficulties in financing the project or in marketing power and energy during the first few years of operation. · Preliminary financial studies have been conducted to determine the probable nature and extent of the problem of high front-end loading as well as to identify potential strategies for alleviating this. These studies wi11 continue in 19&.!-. Insofar as marketing is concerned~ it must be assumed that the maximum price which Railbelt Utilites would pay at any given time for Susitna power and energy is equal to or less than the avo·ided cost of producing power and energy by the best available alternate means. In the initial year .of operation deliveries from Sus1tna wi11 replace power and· energy generated by existing thermal power plant and the avoided cost will be related to fuel. operating and maintenance expense. Only when the existing capacity reaches the point of needing replacement or new demand emerges, with which this existing capaci·ty cannot cope'" will it be possible to edge the Susitna price of energy up to the full cost. The ongoing studies will deal with practical arrangf!ments which can be made with the Railbelt Utilities to achieve equitable marketing terms under which Susitna energy can be introduced to meet a substantial portion of future system needs. 14 -PUBLIC PARTICIPATION PROGRAM An aggressive public participation program was initiated for the Susitna Hydroelectric Project. Conducted directly by the Power Authority, major objectives are: -To distribute information to the public, -To sol'icit information from the public, and -To ensure that public input is fully considered in the decision-making . . . process. 25 I ...... I ' I I I I I I I I - I I .,_ I I ' ,, ,. I I Comnunity meetings, workshops, an action system to ensure that response is provided to every conment or question written by the public~ newsletters and mai 1 ing lists· are vehicles by which these objectives are satisfied. Of particular note is the fact that public comnent and concern has directly influenced the course of the Susitna study. Such major changes from original study plans as the conmissioning of a separate an~d indep~ndent alterna:tjv~es . study, the addition of a sociocultural study and an increased level of study for alternative developments in the Susitna Basin were largely prompted by public concerns. The high level of activity in the Public Participation Program is expected to continue throughout the course of the study. 15 • LICENSING AND PERMITIING PROCEDURES Regulatory requirements at Federal, State and 1oca1 levels tend to be voluminous, complex, and time-consuming for any major power development. For the first several years, sa~-isfaction of regulatory requirements wi 11 be the controlling factor on the schedule for final completion of a Susitna project, The most significant initial regulatory requirement is the necessity to obtain a . license from the Federal Energy Regulatory Conmission (FERC). Should project feasibility be established and a decision made to proceed with the work, current plans call for submittal of an application in ·mid-1982 and for receipt of a licens~ by 1985. A detailed analysis of 1 icensing and permitting requirements was conducted early in the course of the work in 1980 and a blueprint was drawn up to ensure that critical regulatory ~chedules can be met. 16 -FINANCIAL FEASIBILITY ANALYSIS Financial analysis and risk assessment has been initiated but only carried forward to a limited extent pending the selection of the preferred development plan and the availability of appropriate capital costs of construction. One purpose of the preliminary financial feasibility analysis has been to establish the "envelop~11 within which the staging., design and operating configurations of Susitna are amenable to market financing based upon reasonable assumptions concerning financial markets and the incl in at ions of investors over the next 20 to 30 years. " . 26 ' I ' I I I I t I I I I ,, - I I J t I I t A computer model, developed earlier for financial analysis of major capital intensive projects, has been tailored specifically to meet the unique requirements of Susitna. Using this model, it is possible to analyze the effect on financial feasibility resuiting from variations in input assumptions .. These iriputs include phasing of major project stages, scheduliflg of construction outlays, energy and power production during initial years, pricing and revenues, returns on investment, contingency provisions, debt requirements, taxes, and financial market conditions. There has been close correlation with work carried out on generation planning, employing the OGP-5 modeling capability (as described in Paragraph 8). Preliminary financial analysis indicates that viable options do exist for funding th~ project with various levels of involvement of the State of Allska. Work during 1981/82. will focus on financial feasibility of the optimized development s;election and will proceed in close collaboration with the financial consultants selected by the Power Authority a~ the end of 1980. 17 ... SECURITY OF PROJECT COST AND REVENUE STRUCTURE Decision makers responsible for public policy and for action within the financial and credit markets~ as well as those at regu1 atory agencies, must be confident that the probability of unforeseen events seriously distorting the objectives of the Pow~r Authority and its planners is sufficiently remote that government and private investors should comnit substantial financial resources to the Susitna Project. A detailed risk analysis will be made of the various influences and possibilities~ no matter how remote, that might impact the security of the project cost structure and its revenue flow. In particular. consideration will be given to risks, and to the formulation of contingency planss applicable to: Potential variations in ~apital costs -Cost escalation -Cost overruns -Delays -Events leading to noncompletion -Serious outages during operation -Failure of revenue from power resources -Regulatory issues ~ Arising from the study of project cost and revenue structure will be consideration of the need for completion and/or other guarantees and revenue assurance requirements. The aim wi 11 be to develop strategies and procedures which will minimil.e risk in each category and provide for an acceptable balance of residual exposure and benefit for the financing entities which might be involved in the Project~ 27 I I ' I I .- 1 I I I I I I """ I --•-'WI J ' I t I 18 • ORGANIZATION AND MANAGEMENT Project control structures, p9licies and procedures have been developed and put in place t£J ensure that continuing project activities are in the best interests of the State~of Alaska and its populace. The Executive Director of the Power Authority serves as Project Manager for the State of Alaska. He is assisted in turn by a project staff which includes As$iStant. Project Managers for Technical Output and Schedule and for Budget and Finance. A Project Engineer within the Power Authority devotes his full-time attention to monitoring and coordinating project work. Within the Acres organization, a Project Manager is responsible for direction of the activities of a large group of technical personnel. He is assisted by a Deputy Project Manager, a rechnical Study Director, and a Resident Manager (in Anchorage). · External Review Panels have been established both at the Power Authority• s level and at Acres• level to provide an independent check on the adequacy and accuracy of completed and proposed study activities. Major subcontractors assisting Acres in the performance of its work include: -R&M Consultants, Incorporated -Cook In let Region Incorporated in association with Holmes and Narver -Terrestrial Environmental Specialists -Woodward Clyde Consultants -Frank Moolin and Associates -Robert W. Retherford Associates -Other Alaskan finns providing transportation., supplies, and logistical support ~ 19 -IMPLICATIONS OF PROCEEDING The Governor of Alaska and the State Legislature wi11 receive a repo·rt on or before March 30, 1981, wherein the Power Authority must recofm1end whether work ·should continue on the Susitna Hydroelectric Project. The Power Authority has selected four particular issues for detailed consideration. Conclusive proof that any one: of these issues presents an insurmountable barrier would lead to a reconmendation by the Power Authority to terminate the study. Briefly summarized., the issues are as follows: -Are the forecasts too low to require any major generation additions over the next 30 years? -Are seismic risks so great that safe development cannot occur? 28 ' I .l ···-..,..- 1 .. ' I t I I ' I· I ~. I I ' I I I I -Are anticipated environmental losses unacceptable? -Is there a significantly lower-cost set of alternatives which will satisfy demand forecasts through the y~ar 2010? No barriers have been discovered during the initial year of study which would lead to an affirmativ.e .~swer to .any of the listed questions. Even so, def in it tve answers have not y~t been deve 1 oped for .. a 11 of the issues. Continuing the study would provide the State with an opportunity to make sound decisions in the future as to whether Susitna hydroelectric potential should ultimately be developed. Terminating study efforts at this time would result in avoiding the significant costs of further investigation and analysis on Susitna. 29 I · 2 · ... ~PROJECT SCHEDULES .. I ·:.· ' II I ~I.~ . I I I I I· I I I I ,,~ . ' I I I 1\ I I • 2 ~ PROJECT ·scHEDUlES The Plan of Study Master Schedule is shown on the 3 attached Figures.. f: - - 10 Ot5CRII"ll01t •• - • l • -· •• ••• •~.· • •• --- I 7 I • I • ' 4 I a 6 a I £C11VIT!ls •~ 10 UClm£ UPUC.\tWlk I attMta P!ll!!ll ta I.IIIUIO ~ toHS"'--Ctat \.aNS~t~G t--------------------------------------r------------------------~-----------r----------------~r------------------r------------------~------------~~~~~------~'~ BOO ltll ltU IJIS 1114 lit~ " . la ...... "' ....... at& ••• e1 ateta atD1 •............ .,. aaate aUII !!!!!~r·!!_•!!•!!!!!J!•!!•:!·~·~·~-!!!~t,-!;·~ .. !!~~0!!.·- ----~-----J·------------------------!~~--~~--~-~--~~--f--r--~~--f-~--f--t--f--f--f--t--t--;'--t--t--J--t--t--f·--t--t--J--t--t--t--~-t--t---;r---t----1~~•••••~~~~ fOUO.~\ltM~ UftJCjl(llol ~ ... A a • ~ i ............... ._.... • t • SUSITNA HYDROELECTRIC PROJECT PLAN OF STUDY MASTER SCHEDULE t • t , ......... I Him 1~ .. 1 .. . . "~--' .. ~ "I) -----;...------= ·=·=~~= .·: '•.- I ·, ·o··· . . . . -·~·_,._. '.' ,.-\ /_j :1-.~-. . -------::-.--,---..---- c I I'· I I I I ·I I I I I I ·I I I I I I I I .. 3 -NOTES ON SUSITNA BASIN DEVElOPMENT SELECTION 3.1 -Introduction Section 3.2 of these notes briefly outlines the results of the development selection process undertaken to arrive at the proposed Susitna Basin plan~ i.e. the W"atana/Devil Canyon dam development. A brief description of the results of th.e comparison of rail belt generati_ng scenarios, both with and without th.e Susitna Basin development, is also presented in Section 3.3. The Appendix contains tabJes summarizing the parameters used for the systemwide economic evaluation of the various Susitna Basin development plans and the all thermal generating scenario. It also contains results from the generation planning model used for economic evaluation. 3.2 -Evaluation of Susitna Basin Development Plans (a} !ntroduction The Susitna Basin development studies commenced with the selection of 12 potential dam sites within the basin (see Table 1 and Figures 1 and 2). As shown in Figure 3, these sites were then subjected to a screening process incorporating economic, environmental,.and total energy contribution criteria. In cases where two sites were located sufficiently close to each other and could be regarded as alternat;ive sites one of them was also screened out. This screening exercise . resulted in the most upstream sites such as Tyone and Butte Creek being screened out by the environmental, economic, and total energy contribution criteria. The energy potential at these sites is of a •. I I I I I I I I I I I I I I I I I I I smaller order of magnitude that the major basin development options. Although also of low energy potential, the Maclaren and Denali sites were retained as they h.ave potential for upstream regulation of flow for the 1~rger power developments downstream. The two downstream sites, Gold Creek and Olson, were screened mainly because dams at these si:tes would impact upstream anadromous fish spawning areas in Portage Creek. All other dam sites are located upstream of Portage Creek which is known to represent the upstream limit of fish migration on the Susitna. The Devil Creek site was screened as it represents an alternative to tne High Devil Canyon site. Follow.ing the screening exercise and utilizing the assistance of operations research techniques and engineeri~g layout and cost studies, tfie most economic basin development plans were selected. These plans were based on developing combinations of dams at,, the sites remaining after the screening exercise. This process revealed that the develop- ment plans incorporating dam combinations at Watana/Devil Canyon, High. Devil Canyon/Vee, and High Devil Canyon/Watana are the mos.t economic. Taole 2 lists all the development plans selected and the associated costs and ene.rgy yields. Preliminary economic analyses indicated that it is not appropriate to stage actual dam construction out that th.e powerhouse construction at the larger dams such as Watana and High Devil Canyon is warranted. Environmental assessment of the plans indicated that river flows resulting f"om daily peaking operations from the downstream dams could not be accepted. This required the introduction of reregulation facilities in certain cases and reductions in installed capacities at I I I I I I I I I I I I I I I I I I 'I downstream dams in others. Table 3 lists the modified plans. Based on the above information, it was decided to conduct a more thorough evaluation of the following two basic plans. -Plan El.S: Watana dam with two 400 MW powerhouse stages followed by Devil Canyon dam with a 400 MW powerhouse. -Plan E2.3: High Devil Canyon dam with two 400 MW powerhouse stages followed by Vee dam with a 400 MW powerhouse. ~ It was also decided to investigate a long power tunnel alternative to developing the head at the Devil Canyon site as an alternative to the dam. This pian is referred to as 1.5 in Table 2. The following subsection outlines the plan evaluation process and describes the selected development plan. (b) Evaluation of Basin Development Plans The evaluation process used involved consideration of the attributes of the various plans and a ranking of these plans based on comparisons of these attributes. (i) Attributes The following ·attributes are used to evaluate the short listed . basin development plans: I I I I I I I I I I I I I I I I I I I -Economic The parameter us.ed is. the total present worth cos.t of the total railbe1t generating system for the period 1980 to 2040. This parameter is evaluated using an "economic" discount rate of"3%", 0% general escalatiQn and specified rates of fuel cost escalation (see Appendix). The· generation planning model OGPS was used to plan the generation sequences for the 1_980- . 2010' period. The 2010· generating system configuration was assumed to remain constant for the 2010 to 2040 period for purposes of evaluati·ng the total system present worth cost. -Environmenta 1 A qualitative assessment of the environmental impact on the ecologic, cultural, and aesthetic resources is undertaken for each plan. Emphasis· is placed on identifying major concerns so that these could be combined with the other evaluation attributes in an overall assessment of the. plan. -Social This attribute includes determination of the potential nonrenewable res.ource displa::ement, the impact on the state and local economy and the risks and consequences of major structural failures due to seismic events. -Energy Contribution The parameter used is th.e total amount of energy produced from the specific development plan. An assessment of the energy development foregone is also undertaken. This energy I I I I I I I I I I I I I I I I I I I loss is inherent to the plan and cannot easily be recovered by subsequent staged developments. (ii} Evaluation Process The various attrifiutes outlined above have been determined for each plan and are summarized in table form. Some of the attributes are quantative while others are qualitative. Overall evaluation is based on a comparison of similar types of attributes for each plan. In cases where the attributes associatf.Jd with one plan all indicate equality or superiority with respect to another plan, the decision as to the best plan is clear cut. In other cases where some attributes indicate superiority and other inferiority, these differences ar·e high- lighted and trade-off decisions are made to determine the preferred development plan. In cases where thess trade-offs have had to be made, they are relatively convincing and the decision making process can, therefore, be regard.~d as fairly robust. In order to stmplify the overall evaluation process, it is conducted in a series of steps. At each step, only a pair of plans is evaluated. The superior plan_is then passed on to the next step for evaluation against an alternative plan. The results of this exercise are discussed in the following subsection. I I I I I I I -1 I I I I I I I I I I I (iii) Results of the Evaluation Process - The first step in the process involves the evaluation of the . Watana/Devi1 Canyon dam plan and the Watana/Devil Canyon tunnel plan. As Watana dam is common to both plans, the evaluation is based on a comparison of the Devf1 Canyon dam and tunnel schemes~ Devil Canyon Dam Versus Devil Canyon Tunnel Table 4 lists the total present worth costs and Table 5 summarizes the economic evaluation. The results clear1y demonstrate the economic superiority of the Devil Canyon dam scheme. The difference in present worth system costs amounts ' to $680 million. A general description of the environmental impacts associated \'lith developing the Devil Canyon/Watana plan is given in Table 6. This information has been used t~ set up the environmental evaluation in Table 7 which indicates that the tunnel scheme has less environmental impact than the dam scheme. Table 8 lists the social attributes and indicates that the dam scheme has a higher potential for displacing nonrenewable resources than the tunnel scheme, and is therefore, superior. The impacts on the state and local economy and risks due to seismic exposure are judged to be similar for both schemes. Table 9 deals with the energy contribution attrioutes and illustrates that the dam scheme develops more of the basin potential than the tunnel scheme. The overall evaluation of the two schemes is summarized in Table 10". 'The dam scheme is judged to be superior since the cost savings associated with the dam are I I I I I I I I I I I I I I I •• I I I considered to outweigh the relatively modest reduction in the overall environmental impact. The second step of the development selection process involves a comparison of the Watana/Devil Canyon and the High Devil Canyon/Vee development plans. Watana/Devil Canyon Versus High Devil Canyon/Vee Table 4 summarizes the economic parameters while Table 5 outlines the economic evaluation of the plans~ The Watana/ Devil Canyon plan is economically superior by $520 million. Table 6 outlines· the environmental impacts associated with the two plans while Table 11 summarizes the environmental evaluation. The Watana/Devil Canyon plan is judged to be environmentally superior. Table 8 summarizes th.e social evaluation and Table 12 the energy contribution evaluation. The Watana/Devil Canyon plan is superior in terms of both these attributes. Table 13 summarizes the overall evaluation and demonstrates the overall superiority of the Watana/Devil Canyon plan. (c) Selected Development Plan Based on the above discussion, the Watana/Devil Canyon development plan is regarded as the optimum Susitna Basin plan. Currently, engineering studies are in progress to further refine. the size of the development (dam heights, installed capacities~ etc.) and the design concepts. Figures 4 to 6 illustrate the operational characteristics . of this development plan for a typical 30 year period .. I, I I • --I I I .I I I I I I I I I I I I I 3.3 -Comparison of Generation Scenarios Plan The selected Susitna Basin development plan has been compared with a limited number of alternatives by comparing generation scenarios for the Railbelt Region with and without the Susitna Basin development. The two basic Railbelt generation scenarios compared are the a11 thermal scenario which relies on coal and gas fired generation and the with Susitna scenario incorporating the Watana/Devil Canyon dam plan as well as supplementary coal and gas fired generating facilities. Comparison of these two scenarios is based on the same attributes used for the Susitna Basin development selection. Table 14 summarizes the economic attributes and clearly indicates the superiority of the generation scenario incorporating the Watana/Devi1 Canyon plan. The superiority is maintained over wide ranges of anti~ipated future load projections and of the economic variables such as capital cost estimates, discount rate, fuel costs, fuel cost escalation, and economic plant life. The social comparison is summarized in Table 15. The scenario in.corporating the Watana/Devil Canyon plan offers greater potential nonrenewable resource conservation. However, there is insufficient information currently avai. 1le to undertake quantitative comparisons of impacts on state and local economies or of relative seismic exposures. Comparisons at this stage are, therefore, somewhat subjective-~· Table 16 broadly summarizes the environmental impacts associated with the two scenarios. However, specific information on potential future coal-fired generating sources is not available at this time and overall comparison is consequently uncertain. An attempted comparison is summarized in Table 17 from which it is tentatively concluded that the scenario with the Watana/ Devil Canyon plan appears to be superioro ----- - - - - - -·--- - - - - - l .. . ' f i: '- ' 1-r~ t SCALE: i r ·. \ ,J ..../' _,,., ~ k1 '111 6\1 . lYON£ 4 I CANTWELI- 1111 '~' \ ~~ ( rWJNE' ,.-r._J----~ 4fll""',., t J ,1 .- r '< . it J ' ~' . LOCATION Of DAMSITES PROPOSED BY OTHERS FIGUR~ I iil .• --~---------------- P'ORTAGE CR. 100 .... l=f ct ~ zooo!. ~ t:J fJ) > ~ ·22001 200 120 140 160 180 RIVER MILES OSHE.TNA RIVER ·.-----20008 I I I F rd' ~--~·""Tiilr. -TYONE RIVER ~----------2000' ! I I I --rr MACLAREN RIVEiil ~ _u2200 1 I I I ' I I I I I I : 234o·J 220 240 260 280 SUSJTNA BASIN PROFILE AND POTENTIAL DAM SITES FIGUR~ 2~~~~~ ------------------- PREVIOUS 'l STUDIES AND FIELD RECONNAISSANCE 12DAM SITES GOLD CREEK DEVIL CANYON HIGH DEVIL CAN'YON DEVIL CREEK WATANA SUSITNA m VEE MACLAREN DENALI BUTTE CREEK TYONE SCREEN . ENGINEERING LAYOUT AND COST STUDIES 7DAM SITES COMPUTER MODELS TO DETERMINE LEAST COST DAM COMBINATIONS 3 BASIC DEVELOP· MENT PLANS COMPUTER M0fll£LS TO EVALUATE -POWER AN~ ENERGY YU3LDS -SYSTEMWIDE ECONOMICS CRITERIA DEVIL CANYON OBJECTIVE ECONOMIC WATANA l DEVIL CANYON ATTRIBUTES WATANAIDEVIL CANYON ECONOMICS HIGH DEVIL ENVIRONMENTAL I ~~~X~~ ~JfrNATIVE SUSITNA m: ENERGY VEE CONTRIBUTION MACLAREN -------DENALI ------HIGH DEVIL CANYON/VEE HIGH DEVIL CANYON I WATANA ADDIT!ON\L SITES PORTAGE CnEEK ECONOMIC ENVIRONMENTAL SOCIAL ENERGY CONTRIBUTION DIS HIGH DEVIL CANYON 0/S WATANA SUSITNA BASIN DEVELOPMENT SELECTION PROCESS ill FIGURE 3 . . I AVERAGE MONTHLY ENERGY I ! I I 11 ! r n ~ !'-~ ~ fl r. 11n r u il ~ J J1 1 II l n 1 n II I ..J n r~ Jlr l J1 lJ I \ rl j1 ~ l . J ~ lt ILl I J 1 r l L, >J. ...... l J\1 11 I I) l lJ l Lf l 1 u' ~J f \_ L. w J~ k IL ~ ~ \...__ fl-_ k il-~ !LJ,L 'l.,.._ 1_ ~.r ~ 1.__ fl-.. I"L_ l ~ ,W It-. "' r:"") ::-. c-r. r. .. r: r-. r.: '~ . ~ . . ~ • ' 1 950 l 9 .. d 19....... l 9::.>3 1954 1962 l96~ !964 1965 195~ 1957 a968 1969 !970 1971 AVERAGE MONTHLY INFLOW . I I lSPII l ' LS ! ~ JLJ , 'I II t ! l ~ -T RBINE I l I I ! -• ' I ~ .r--...._r ~"' ~ r.J ~ ~ -~ ~~ ~Ill ~ ~ ~ ~ ... ~ ~ ~ ~j l.~ ~ ~!I ~ N ~~ I -• . . 1950 )951 1952 1953 1954 19:..5 195& 19!:>7 1958 1959 1960 l96l 1962 1963 t964 1965 1966 1967 t968 1969 1970 1971 1972 1973 r9 7 4 1975 1976 1977 1978 i979 ' AVERAGE MONTHLY DISCHARGE l ' > ' . ~· '• --lj I .-MAXU UM E~VAT~ON l 1\! \ f \{ 1\/1\ l \ J 1\f 1\ f 1\/ \ f \I \f ~~ 1\/ \J \t \{ 1\1 \/ \ ;1 r\ I \{ \ I ~J \r ~ Jl\/i\ J' l v v 1J ls-l lJ 1J 1J 1J 1-.j lJ LJ Lr u lr' \1 '1J lJ l.J 1..-1 v \ t \r \J 1J v 1J lJ . lJ L-l 1,.1 1l \~ I I t_M !NIMU~ ELE'.JA TION l I I . . r. c .,. .. .. ~ .... ,.. -. . ·~ . -. c ' !950 t951 19::.>2 19a3 IY~4 1955 1956 1957 )956 1959 1960 t~Q! !962 1963 t964 19~5 1966 t9~7 1966 AVERAGE MONTHLY ELEVATION NOTE : WATER YEAR OCT.-SEPT. STAGE 1-WATANA RESERVOIR ( 400 MW) OPERATION OF TH~=" WATANA I DEVIL CANYON DEVELOPMENT PLAN E 1.5 FIGURE 4 •• ------------------------------~--------------~--------------~----------------------~------------~----·--~----------------------------·---------------- I I ·I I I I I I I I I I 'I I I I I -·I I 0 • 0 0 n o Oo * 0 "¢ (f). u..o (.)~ '-J 0 3 (\J 0 _j LL ::z:g . ,_, . Jl ~ L l { I \ n Jir 1 J1 1J l.J ~ k I r-: l 1 J 1 1 !1 i1 .t, 1 1 J jl J l J u r'--~ ~ \...__ ~ L l._ ~ 1975 1975 1977 1975 1979 I Jj_ I 1 1fj l ID 0 n l .I ~ l,_ Ll ~ ft. )l 1~1 l.P l ~ l r1 r fl '1. r l l ~_j t 1 I u u ~t l lJ L L IL-l.. ~ J ~1-!L fl._ ~ L u r . "' ... .. • r-. ' • . . -. . . o Ta~o t9at !9J2 19a3 t9~4 1955 1956 1957 1QSS 1959 1960 l96t 1952 1953 t954 1965 195~ 1967 1968 !969 1970 a9?l 1972 197~ t974 1975 ,g7~ !977 1915 1979 * . 0 -o (f) • LL_O oN r ~ ~ ~ j_ ~ ' ,.. rt,j ~ ~ ~ rt,j AVERAGE MONTHLY INFLOW I l I ~ r n 1 ~il ~ ~ ~ ~ ~ ~-l ~ ~ I I l I I l I l· I i • ' I SPILLS n ~TURBINE nl ~ rvt ~ ~~".r ~ ~ ~ ~ ~rJ ~ ~- l c r: c· . . . . - w Do O:::o <( • ro. I9a0 1951 19a2 19a3 1954 __ 1955 1956 1957 18~8 1959 1960 t961 1952 1953 1964 1965 1955 1967 1968 t969 1970 t971 1972 1973 1974 1975 191!~ i977 1978 1979 u (f) AVERAGE MONTHLY DISCHARGE -0 ., AVERAGE MONTHLY ELEVATION NOTE: WATER YEAR OCT.-SEPT. STAGE 3-WATANA RESERVOIR (800 MW} OPERATION OF THE. WATANA/ DEVIL CANYON DEVELOPMENT PLAN E 1.3 FIGURE 5 I I .I I I I I I I I I I I I I I I I I z w I") 0 Oo ,...., (/) LLO 0~ '--0 :J:: (\) 0 _J LL zg -. n n ,.J J u ~ ~ o I 950 t 951 (f) LL Oo -o LUo C) C\1 a::: <C ::r: Oo (1)0 ~ i:-1 0 ! 950 a - . z ao 0 . 1-0 <( L"') I") >~ w _JO l..l.Jo . 0 lf) ~ . ... I ..,. ~ 19 .... 0 ! 951 f I I~ r., ~ ·~ r. fl. li an I~ r ... \ n I Jl I'"' l 1. J J L u ~ L l._._j 1.-l__ ~ !L. l._ ... 19!;3 1954 1955 1956 1957 1958 1959 ]950 I 961 ~~·I' I . I ... J ..J ~~~ r'lJ'l ~ ~ ~ ~ f""~ ~ ..... ~ f'"'"'lJ'L 1952 1953 I 954 1955 1956 19.57 . J 958 .. 1959 1960 I 951 ' . - I r • 1952 1953 1954 1955 19~5 19 .... 7 1956 1959 1960 196t AVERAGE MONTHLY ENERGY I . I I f I I • j • fJ G -)I I rJ r ~· f :l IL 1 l j n I '] _1" J 1 ~ ) L J r 1 1 f1 JLfl I f)l l1 1 I I u l Lit L ~ k~ ll_ L rl-J L [L._ fl-~ [L_. ~ fl-_ ~-lL-[t-,_ ,.,. . . . . . ,, -. 1972 1973 1974 1975 19?? ,977 t978 191'-s 1962 1963 1964 19n5 1966 1~'57 1958 1969 1970 t97'l AVERAGE MONTHLY INFLOW I I t . I i i ~SPit LS J I » -l I ~ I IT ~RBINE 1'--tLJ .. . _... J • ~ rv ~v ~ rv ~ lf~Ulf ~ Y""'"'lJ l.l ~ ~ ~I..J jV1._, fl"''J'U . t J 1 ~62 1 963 I 96.1_ 196~ 1 965 1 967 1 968 1 959 1970 t 971 AVERAGE MONTHLY DISCHARGE 1'972_ 1973 1974 1975 1976 1977 1978 1979 . ··-· "" ~MAXJI\ UM Ell VATIO~ I I ) t ~. ~ tMINIMUM ELEVA ION . I .. . r:: • c: • " 1962 1963 !964 196~ 1956 1957 1966 19~9 1970 1371 AVERAGE MONTHLY ELEVATION 1372 1973 1974 197~ 1975 1977 1976 197B NOTE : WATER YEAR OCT.-SEPT. STAGE 3-DEVIL CANYON RESERVOIR (400MW) OPERATION OF THE WATANA I DEVIL CANYON DEVELOPMENT PLAN E l.3 FIGURE 6 [ii I ---.. ---·-------- TABLE 1 -POTENTIAL HYDROELECTRIC DEVELOPMENT Average Economic* Dam Capital Installed Annual Cost of Source Proposed Height Upstream Cost Capacity Energy Energy of Site "(yQe ft. R~ulation $ X 106 (MW) Gl>Jh $/1000 kWh Oat a Gold Creek** fill 190 Yes 900 260 1,140 37 USBR 1953 . Olson (Susitna II) Concrete 160 Yes 600 200 915 31 USBR 1953 KAISER 1974 COE 1975 Devil Canyon Concrete 675 No 830 250 1,420 27 This Study Yes 1,000 600 2,980 17 " High Devil Canyon II (Susitna I) fill 855 No 1t500 BOO 3,540 21 II Devil Creek** fill Approx No -----850 Watana fill BBO No 1,860 800 3,250 28 " Susitna III fill 670 No 1f390 350 1,580 41 II Vee fill 610 No 1,060 400 1,370 37 II . ' Maclaren** fill 185 No 500 55 180 124 u Denali fill 230 No 440 60 21!-5 81 II Butte Creek** fill Approx No -40 .130*** -USBR 1953 150 Tyona** fill Approx No -6 22*** -USBR 1953 60 *Includes AF~C, Insurance, Amortization, and Operation & Maintenance Costs. **No detsiled engineering or energy studies undertaken oo part of this study. ***These are approximate estimates and serve only to represent the potential of these two dam sites in perspective. - ----------------.. TABLE 2 -Susitna Development Plans Cumulative Stage/Incremental Data System OataJ Annual Maximum Energy Capital Cost Earliest Reservoir Seasonal Product ion Pllamt .$ Millions Construction On-line full Supply Draw-firm Avg. r-ac::tl:.nr Plan Stage Construction (1980 values) Period Date 1 Level -ft. down-ft GWH GWHo yrs. ~ 1 0 1 .1 Watana 22.25 ft BOOMW 1860 9 1993 2200 150 2670 J250 4-Sl o2 Devil Canyon 1470 ft 600MW 1000 6-1/2 1996 1450 150 5310 6230 5.tl TOTAL SYSTEM 1400MW 2860 1.2 .1 Watana 2060 ft 400MW 1570 8 1992 2000 100 1710 2110 Mll .2 Watana raise to 2225 ft 360 3 .1995 2200 150 2670 2990 a:s .3 Wai:ana add 400MW capacity 130 2 1995 2200 150 2670 3250 4,~ .4 Devil Canyon 1470 ft 600MW 1000 6-1/2 1996 1450 100 5310 6230 ~13 TOTAL SYSTEM 1400MW 3060 1.3 • 1 Watana 2225 ft 4GOMW 1740 9 1993 2200 150 2670 2990 ll;$ .2 Watana add 400MW capacity 150 3 1994 2200 150 2670 3250 4.4;. .J Devil Canyon 1470 ft I 600 MW· 1000 6-1/2 1996 1450 100 5310 6230 5!11 TOTAL SYSTEM 1400MW 2890 1 0 4 1 Devil Canyon 1470 ft 250MW 830 6 1990 1450 100 1250 1420 6.S 2 Watana 2225 ft 400MW 1740 9 1996 2200 150 3920 4410 "Jl 3 Watana add 400MW 150 3 1997 2200 150 3920 4670 s·t 4 Devil Canyon add 350MW 200 3 1997 1450 100 5310 6230 Sl TOTAL SYSTEM 1400MW 2920 - - -- ------- TABLE 2 (Continued) Cumulative Stage/Incremental Data System Data:t Ann~al Maximum Energy ' Captial Cost Earliest Reservoir Seasonal Production P.t<bnt $ Millions Construction fin-line Full Supply Draw-firm Avg. f ac--ti:.OJ: Plan Stage Construction (1980 values) Period Date 1 Level -ft. down-ft. GWH GWH ~~ yrs. 1. 5 1 Watana 2225 ft BOOMW 1860 9 1993 2200 150 2670 3250 4~ 2. Watana add 50MW Tunnel 330MW. 1500 . 5 1995 1475 4 4890 5430 5-3; TOTAL SYSTEM 1180MW 3380 2.1 1 High Devil Canyon 1775 ft 800HW 1500 8 1994 2 1750 150 2860 3540 >1! 2 Vee 2350ft 400MW 1060 7 1997 2330 150 3870 4910 4.7i TOTAL SYSTEM 1200M.W 2560 2.2 1 High Davil Canyon 1630 ft 400MW 1140 7 1993 2 1610 100 1850 2110 6ld 2 High Devil Canyon add 400MW Capacity raise dam to 1775 ft 500 3 1996 1750 150 2860 3540 >11 3 Vee 2350 ft 400 HW 1060 7 1997 2330 150 3870 4910 4,7} TOTAL SYSTEM 1200MW 2700 2.3 1 High Devil Canyon 2 1775 ft 400MW 1390 8 1994 1750 150 2400 2730 ~~ 2 High Devil Canyon add 400MW capacity 140 3 1995 1750 150 2860 3540 S,l 3 Vee 2350 ft 400MW 1060 7 1997 2330 150 3870 4910 4ij' TOTAL SYSTEM 1200 2590 3.1 1 Watana . 2225 ft BOOM\'! 1860 9 1995 2 2200 150 2670 3250 4& 2 High Devil Canyon 1470 ft 400MW 860 6 1998 1450 10G 45.50 5280 50 3 Portage Creek 1030 ft 150MW 650 5 2000 1020 50 5110 5960 50 TOTAL SYSTEM 1350MW 3370 NOTES: 1. Allowing for a 3 year overlap construction period between major dams. 2. Assumes fERC license can be filed by June 1984, ie. 2 years later than for the Watana/Devil Canyon Plan 1. . . ----.. ; ----------. TABLE 3 -Sslected Susitna Development PlAns (Environmental) I Cumulative, Stage/Incremental Data System Data:. . Annual Maximum Energy l Capital Cost Reservoir Seasonal Production PI cm-~'t $ Millions full Supply Draw-firm Avg .. facto::lt' Plan Sts=toe Construction (1980 values) Level -ft. down-ft. GWH GWH ~' E1 .. 3 1 Watana 2225 ft 400MW 1740 2200 150 2670 2!a00 83 l 2 Watana add 400MW capacity and Re-regulation dam 250 2200 150 2670 3250 46: 3 Devil Canyon 1470 ft 400MW 900 1450 150 5520 6070 sa: I I TOTAL SYSTEM 1200MW 2890 E2.3 1 High Devil Canyon 1775 ft 400MW 1390 1750 150 2400 2730 7$ I 2 High Devil Canyon add 400MW capacity and I re-regulation dam 280 1750 150 2860 3540 511 3 Vee 2350 ft 400MW 1060 2330 100 3870, 4910 47' TOTAL SYSTEM 1200MW 2730 E2.4 1 High Devil Canyon 1775 ft 400HW 1390 1750 150 2400 2730 7f:l 2 High Devil Canyon - add 400MW capacity 140 1750 150 2860 3540 5t Portage Creek 1030 ft 150MW 650 1020 50 3410 4190 50 3 Vee 2350 ft 400MW 1060 2330 100 4430 5540 47: TOTAL SYSTEM 1350MW 3240 ' 1 I I I - I I I~ I I; I I -? • I I I I I I ' Parameter Capital Investment Fuel 0 TABLE 4 -Economic Backup Data for _____ ...;E:..;;.v.=.a l.:...;u::.;;a:..;:;.t..;.;i o::;.;.n:.....=.o.:..f ~P~l.=.an:.:.;s:.....- Total Present Worth Cost for 1981-2040 Period $ Mill io!L,{% Total) _ _ Generation Plan with High Devil Canyon/VE!e 2840 (44) 3230 (SO) Generation Plan ~<fith Watana/ Devil Canyon 2750 (47) 2750 (47) All Thermal Generation Pl~ns 2520 {31) 5200 (64) 410 (5) Operation and Maintenance 390 (6) 350 (6) Total: 6460 (100) 5850 (100). 8130 (100) --·PI --- - ••• --~- TAI!lE 5 ECONOOIC EVALUATIOO Of DEVIl CANYON DAM Atll TUNNEl. SCI-Itl£5 Atl> WATANA/OCVIL CANYOO Atll HlCH OCVIL CANYOO/YEE PlANS ECONOHIC EVALUAflON& Base Case lOAD GROWTH SensUivU low High PERillO or ECONOMIC ANM. YSIS Period shod:: ned to (1900 -2010) OlSCOOOt RAT£ FUEl COST rt£L COST ESCALATION ECOOOHIC iiiERHAl PlANt LIFE 5:1;. a: {interpolated) 9: 8~ basic fuel coat o: fuel cecal at lon 0: coal escalation 50: extension 01 eltlens ion 680 650 N.A. 2Jil 520 210 H.A. 160 As both tho capital and fuel coats associated with the tunnel achmae and tt.D.C./Vee Plan are hi~er than for Vatann/Devil Canyon plan any changes to thesa paraeters cemot reduce the Devil Canyon or Watana/Oevil Canyon net benefit to below zerc. ( Reslitks EcD(l(llaic ranking: Devil Canyon dall achellle ia superior to Tunnel echelle. Wataoa/Oavll Canyon dala plan is a rlor lo the Hi CevU CM dart len. Shorter per ~od of avllltmUon docreatu~a eeDflOI&lc dlf- ferencea, RIRkl 11!11Dlna unch d. Ranking re~~&lna mchanged. - --.. --7 I --•• ---- lADlE 6 EPdiR!JI'f£NTAL UI'ACTS ASSOCIATED WUH WATANA/DEVIL CANYON Atll HIGH J)EVll CANYON/~EE DEVELGPJ£Nt PLANS ------------~---~-----------T----------------------~------------------------~----------------------~--------------------------------- River Environraenlal Difference in !~act ldonllflcatlcm Rench Attributes •-----~C!!:onc~e~r.!.!ilB:!_ __ -l~----.....!o!!!fl....!:t!!:wo~p!!:i;!!ans!.!!!. ___ -1-----o2.!..r..!d!!l!.f~fe:.!r~e!!nceE!!.-:;'("'---1--~t.pp~~lr!.ai!.!B!.!!D!!.l..::~"·~,..4n.....-n!:!!!~1t ______ _ ---~==~--~---=====~---~ ' Downatre~a of fcological Otcnge in water quality i'il Devil Canyon Gr.d ~•tr e2 !t affacta Significant difference between Devil Canyon Dev ll Canyon to Watsna DElli Site Cultural Acsth8t~c/ land Use Ecological Cultural ~athelic/ land Use Ecological Cultural Aeathellc/ land Uae fish and wildlife. plans. NO downstrea. srcheologica concern. Poeaible socio-cultural effects on dotmaheBIII co• IIIUnlt;ies. Otarlge ln fltm ao lt affects uttllzatlon of the . lower r!~r. Mlni•al ecological concern in the canyon. Potentlal Inundation Qf archeological sltea. !ni.lldat!cn of unique Devil Canyon. Ut.Uizatlon of the river valley by MOOSe and baar. Caribou crossing in fog creek area. Reeldenl:. fisheries lnmdatlon of Archcologlca altos. fl) Slgniflcont difference between I ploos. 00 Slgnlilcant dlffarence between -~1.-ta • Hlnl•al differ~nce 1n pbtentlal llf'acl. Probable •lnl~l difference due to rugged nature or the canyon. Hlni111al difference in !~~pacta 8Laualng a re-regulation do. is built dowm~tre&lll or me. Difference between plans. Hinihlal difference between plana. Hinlmal difference between plans. ln the upper portions of thls reoch wore of the river valle would be Inundated with the WC{~s\ll 81! ~~ t=l :I:~~U&t is 1.4SO•) w!th a potential greater !~act on wildlife re sourcea. - Bath plena inundate epproxi- saately the aOIIIB reSL'h of the Susltna Rlvo~ however the lllC/V plan NOUld extr·1ljj op- prodlllltely 1 110re 11ll\e up Devil Ct-eek and l 1110ro 11iles up the Tsusena Creek. Not a factor in plan cnsparlson. Nat a factor in p!~ ~arison. Not c factor in plan ~ariaon. Not a factor in plan C08P&rison. Not • fecte1r in plan COIIIpBrlson. Not a fecto~ ln plan ~arlaon. The wlldlire !~acta in this eectlon would be leas with the ~/DC plan however due to the relatively saall area involved this dlf{oreoce is not a aajo~ factor !n plan eva uat aon. Tha IOC/V pla'l would create a greater im- pact on realdent fieheriea although the rclatl~ difference !n this section of the rive~ ls •lni~al. This difference la con- sidered a •lnor factor 1n plan evaluation. Know twld auupected erd1eolog' Since none of those archeological sites !cal sites exist in thla sec-have been desi~eted as having a •ajor tlon of the rivet·. ti>C/V witl ai~ificance Gild •lliyotlon lleBBUtes ita higher pool elevation has are available, this •inlaal difference a greater possiblllty of !nun is r.onsldered a •inor factor ln plan dated .are archeological alte1 evaluation. loss of land use potential Hiot•sl di;>;'feronce between li>C ~aervoit would Inundate t!>C/V plan results in e slightly great- Loss of aesthet!·. •• ~ plenn. the scenic Ts!Jaena raua toea er lose or eesthetlc end land uae ra- l of land uau potential el•llar sources. lhe difference hes a •inor I for both plans. influence In the overall COII(JBrlson or -------------------~--------------------k--------··-------------·-----~---------------------------------~-------------------------~~t~he~p~ll~an~s~·---------------------------- -- -- River Reach Watana to Vee Data Site Vee d1111 sUe and upatre0111 - fnv i!'tlfWleOtol Attdbutes Ecol1J91cal Cultural Aesthetice/ land Use Ecological are --- - - TASI..E 6 (Cont 'd) ENVIRDIH:NJAL JfoPACl'S ASSOCH\TlD WIHI NIUANA/DE:VIL CANYilt~ Arll HIGH DEVIL CANYCN/VCE DEV£UlMNJ PLANS CCiilCems loss of 1110068 habitat. Impacts on Caribou Migra- tion. Loss of river boH0111 and valley habitat. Loss of archeological eltea. Resour~ agencies ere con- cerned about ~reating access to extensive wilder ness areas. On the other hand certain se~ts of the publ!c desire improved access. Inundation of resident fisheries. Dlffoi'encc in i111pact Of ho Plane Difference between plans. Potential difference botwoen plana. Difference in river valley habitat lo&t. No si~if!cont difference iden- tified to date. location and ext~nt of access could vary between plans. I Difference between plans. ldentlricatlon of difference Watana reservoir floods to el evat lao 2200' fi)C reserwir floods to elevation 1750'. The lol\-er reach of the Wahna Creel< ·~in, lde~Uflod as an J,..m.:-nt IIIOO&e area, would b inundated by the Watana reaor voir. 'The quality of the hab itul and condition of the slil ~latlon of aoose In lh!a arita appears to be decrc•~tlng Caribou crossing has been doc uaented ln Koeina/Jay trook area. Vue t:o the lllrf wlnle drm~down end potentiu for icc shelving Ute Watana reurvol could inhibit caribou crosalnr in the spring. Although the HOC reservoir could have • alMllar effect the probabiltt or !~act la greater for the Watona reservoir. The loss of river bottoa hab- itat ls sl•Uar for both ach-a. loss of roreot alc-n~ the valley slopes would be greater wlth the Watana schelll8. This habitat has beer identified as being ~rtant for birds !Kld beers. Due to the larger area or Ute Watanit reservoir in this sec- tion• tho probability or inun dating arCheological s!tee is increaal!d. Hare extensive road access lfauld probably reaull frt)g! Uu IIJC/V plan due to the coo- struction requirements at Vee site. Access created direct!' by the reservoirs is ai•llar for both echemas in this react of the river. fhe Yeo reservoir •a~l~ poo elevation Js 2JJO'. The Watane reservoir llllixl ..... pool elevation is 2200 1 • The addl Uonsl 130' elevation aasocl- al:ed with the Vee daM would result .in the inudatlon of eppro~J.ately 12 additional Miles of the Susil:na River in this reach, 1-1/2 addltl&nal lliilea of the Dshetna River: m' 12 Miles of lhe Tyone River. Appraisal Judge~~ent the Wata1e plnn would create a greater bpact on 1100se in this reach of the river however considering the declining nature or this IIOOI!e hsbitat the a!grd- c::ance of this lHpoct is considered lea~ than iq~acts that could occur upstre0111 in the Vee reservoir. ihe Watana pion could c::reat~ a greater reotrlctlon on caribou c::roa~lng in this aect.lOil of the river. nul potential impect on caribou le COIIp&red tdth po;. t.enllal iwtpacta upatre811 and considered to b3 !coo olgnlficent. The Watana schenae would create a greater laos or illlpOrtant habitat along the valley slopes ln thfs section of the river. This factor Js conaldered of *'dante importance in pion evaluation. Not a 1110jor factor Jn plan evaluation. Any Susltna develoJllllfJnt will increase SC!:e!!S to this relat ivaly wildernesa area. As it is easler to extend access than to !Jmlt It, echemea with the least lnflorent acceo.a are considered superior This ia conaldored !t Jllldorate factor favoring the Watana achoiN!. The II>C/V plan ranulta In a significant increase Jn tha loss of ~esldent fleherles hahltst In lhie reach or the river. --- - .. Rivet Reach Env lrQillrlental Attdbutes Cultural Aesthetlc/ land Use e W = Wal:ana da DC .: Devil Canyon d!!!!l II>C ::: High Devil Canyon daM V = Vee dBIII .. . . -·. -- TABlE 6 (COnt•~~ EWiiRDff£NlAl IWACJS ASSOCIATED .WUH WAJANA/DEVIl CANYOO Am HIGH DEVIl CANYON/VEE DEVEloMNT PlANS Conccrno lons of .ooee habitat. lapact on caribou algra- tion. !~act of furbearete. IMPact on archeological sites. loss of Vee Canyon. Access to wllderneso areas Oifferencu In l~oct of two Plano Slgnlflcent difference between plana. Significant difference between plans. Difference between plana. Potential difference between plans. NO algnlflcanl difference ba- tween plana. Significant difference between pians. Ident1flcatloo of difference In addition to &!'eas In1.11dat by the Watans reaefvolr, the Vee brpotlldaont wuld floud 20 addltionsl •lies ~~ criti- cal winter l"lver boU0111 habi- tat In this reach utilized by at least three subpopulatlans of aooeo lhct renga over lar aren eatst of the Susltna and nod.h of the Maclaren River ra&eh. Area flooded by WC!V pl110 is historically ueod by Nelchlna caribou hord. IMe to lncreaa tld length or rlver flooded th HDCIV plan would create a greater division of thn telchina herd's rango. ~~· flooded by HDC/V plan consi~red lfi!Portant. to 11011e key furbb~~era, particularly red fo~:. Preliainary studies ~~icate a high potential for dio~~~er of archeological altos along lakes, atrenas and rivera in the easterly region of the ~per Sualtna Basin. Addi- tional sites ere expected to be located near caribou cros- sing areas. The II>C/V plan has a greater probability of inundating potential altea. Aooraiasl .lxlaellent lh8 HDC/V plan MOuld create a greater J~apact en lllD&e in thla eecUon uf tha river. This JBpact m IICIO!Ie is ju~d to be of greater signlfic~ than [he loss of 100as habitat in the Watana Creek area resulting froa the WatanA reservoir. This poteolial negaU.ve effect on caribou Ia considered a ~~ajor factor In the evaluation of the IOC/V plan. ~is furbaorer loss is judged to be ~eater t.han furbearer losses associ- ated wllh the inl.lldctlon of the Watana Creek area. ltle IDC/V plrm is Judged to have a 9teater potential for creating cultural iMpacts in thls section of the river. This is considered a MOderate factor ln the evalUBtion of plans. With this tK/V plan a da Not s factor in evaluation of plons. would be eltuated in tho lowe reaches. of the Vee canyon th ell•lneting lhe existing aesthet lc value of the can~1JO W!tn the ~/DC plan the Vee crmyon would be inl.lldeted to depth of eppro~l•alely 175'. ln addition ~o the difference crested by rocod fiCCaas the for.at.lcm of the Vee re~ervol 1«1Uld open a large SIIIOI.Ilt of tile northeast sect ion or the basin, en Isolated area pre- aenUy used el(bmslvoly by caribou and moose. Due to the possible l~~~pacto on caribou the access into thls region created by the HDC/V plan considered a aajor oega- Uve factor ooaoclated with this plrm. .. - ----... - - •• ---- TABLE 7 ENVIRON'll:NTAL EVAllii\TION Of OCVit CANYON DAM AAO ltN£L SCt£1£ EnvironMent a I -~praisal Identlficat.lon 5chelle. J~d. to_ have (Diffrr6nees in ~act the least potential illpect Attribute Concerns ilf bo schesea) of difference Appraisal .. ~-t lt.l'lOeJ oc Ecological Oownstrea. fisheries Effecto resulting No algnificant difference Not a factor in evaluation or ood WHdllfe fr011 changes ln between scheiles regarding ' sche~~e. water quootlty and effects aownstre~;of qllal!ty. J)evll Canyon. Difference in reach be-With the tunnal schetle 1:00-If fisher les enhan~raent oppor-X tween Devil Canyon ·dam and trolled flows between regula-tunity can be realized the t:un- tllnfl91 re-regulatlon dill'll. t.lon d8lll and dotmaheBIII power• nel scheme offers a. positive house offers potential for ~itigatlon measure not avollablE anadrlllious flaherlea cnhnnce· with tha Devil Canyon d!IIA ment in this 11 aile reach of schetiiEl. This opportunity Ia the rivet'. considered .adcrale a1d favors the tunnel acho1110. Resident fisheries loss of resident Hlni~al dlfferencea be~weeo Devil Canyon d8lll would lnundat« lhla reach of river is not con-X fisheries habitat. ache~~~es. 27 tdlea of the Susitna River aidered to be highly slgnif1cGOI and approxl~loly 2 aileo 0f for resident flahorlea and lhus DevU Crtmk. The tunnel echeal the difference between the wnuld lmndate 16 •Ilea cr lhc acht1111ee Ia Minor and favora tho Susltna River. ttr.nel eche1110. - MHdllfe loss of wildlife Minimal differences between lh~ aoot sensitive wildllfo ha fhe difference in lose of wild-X habitat. schemes. bitat ln this reach is upelte~ life hobltat is considered aod- of the tlJM8l ro-iegulotloo d01 orate end favors L~& tunnel whete there ie no significant oche110. difference between l:he sclleaes ~f.lvil Cao~1i m~~ in . 11' ·~t '""' ~ f' e.~ve..-va ey ween e wa sites resulting in a aoderAle increase In i~acts to wildlife. Cultural Inundation of Potential differences betwee Dus to the larger area inun-No significant sites have been - -archeological sites schemes. dated the proboblUty of !nun-Identified. If dlecovered tliitl detlng archeological altes is gallon measures ure easily lm- JncresP.:!d. plemenled. Therefore lhla CAn- c~rn is not conaldered a factor in scheme evaluation. - Aesthetic/ Inoodatlon of Devil Significant difference the De\'11 Canyon is considered lha aesthetic and to some exten X land Use Canyon. between ache~~~Ss. a unique resource, 80 percent the recreational losses associ- of which l«!Uld be inundated by ated with the development of th the Devil Canyon data ache.c. nit Devil Canyon d0111 is. the lhJa would result ln a loaa of aa n aspect favoring the tunnel both an aesthet!c value plus acheme. the potential for white water recreation. 01/(RAI.l "EVALUAUONt The !unnel schente has overall a lower inrpact: on the envirOMIE!nt. .•. ·, --.... •··.· ... -•. - -...... --: --~-.-- Social Aspect Potential non-rene\'labl e resource displacement Impact on State economy, Impact on local economy Seismic exposure Overall Evaluation Parameter ~ti 11 ion tons Beluga coal, Qyer 50 years. Risk of major structural failure Potential impact of failure on human life Tunnel Scheme 80 TABLE 8 -Social Evaluation of Susitna Basin Development Schemes/Plans Devil Canyon Dam Scheme llO High Devil Canyon/ Vee Plan l '"ln /U Watana/Oevil Canyon Plan 210 All projects would have similar impacts on the state and local economy. · All projects designed to stmilqr levels of safety, Any dam failures would effect the same downstream population. 1. Devil Canyon dam superior to tunnel. 2. Watana/Devil Canyon superior to High Devil Canyon/Vee plan. Remarks Devil Canyon dam scheme potential higher than tunnel scheme. Watana/ .n~vi1 Canyon plan higher than High Oevil Canyon/ Vee plan. Essentially no di.fference between plans/sch~s. I I I I I I ·- I I I · .. I, I I I I ' ,, I TABLE 9 ENERGY CONTRIBUTION EVALUATION OF THE DEVIL CANYON DAM ANO TUNNEL SCHEMES Parameter Total Energy Production Capability Annual Average Energy GWH Firm Annual Energy GWH % Basin Potential Developed (1) f!lergy Potential Not Developed GWH Devil Canyon 2850 2590 43 60 Tunnel 2240 2050 32 380 Remarks Devil Canyon dam annu- ally developes 610 GWH and 540 GWH more average and firm energy re~ spectively than the the Tunnel scheme. Devil Canyon schemes develops more of the basin potential As currently envisaged, the Devil Canyon dam does not develop 15 ft gross head between the Watana site and the Devil Canyon reservoir. The tunnel scheme in- corporates additional friction losses in tunnels. Also the com- pensation flow released from re-regulation dam is not used in conjunc- tion with head between re-regulation dam and Devil Canyon. Notes: (1) Based on annual average energy. Full potential based on USSR four dam scheme (Reference ). I t{ ' I I I I I J I I 'I· '· ,. I I I I I I ' I ' I l TABLE 10 -OVERAbL EVALUATION OF TUNNEL SCHEME AND DEVIL CANYON DAM SCHEME ATIRIBUTE ECONOt~IC ENERGY CONTRIBUTION ENVIRONMEJ~·r AL SOCIAL OVERALL EVALUATION 1 :sUPERIOR SCHEME DEVIL CANYON DAM DEVIL CANYON DAM TUNNEL DEVIL CANYON DAM (MARGINAL) DEVIL CANYON DAM SCHEME IS SUPERIOR TRADE OFFS MADE: . ECONOMIC ADVANTAGE OF DAM SCHEME IS JUDGED TO OUTWEIGH THE REDUCED ENVIRONMEN1AL IMPACT ASSOCIATED WITH THE TU M"II""! t"',..lll""l.tr'" m·u::.L .;)~m:.rn:.. -----~-' •. ' .. . .. - fABlE 11 ENVJI«H£NfAL EVAlUATION IF WATANA/DEVIl CmYOH Am filCH DEVIL CANYON/VEE 0t:VElm'I£NT PLANS ~Aan ~J=l to_ na~m ~a £nviroo.ental Attribute ApprsiBBl ~t leaat oo enU•l .IMPact Plan COIIIIParieon ~/_! W/IJ(; Eco!~ical 1) ISher les . fb algniflcant. difference in effects on mwnsl:t-ea ~ to the IIWidence of the lyone Rlvn. X: anadroeous flaher!ae. Ieser inoodaUon of realP~mt f!!lherlea lllC/V would int.aldato ~~tWrox!aately 95 aUes of the. hebltat and no aignlflcenl dirfereilce ln the . effects on anadtQIIIQua flalwlldas, the W/DC plar • SUsltna River and 28 e!les of tdbutary atre81119 1 In-is judged to have less !..,act: • eluding. the Tyone River. W/DC .would lfltlldate approdutoly 84 111Uea of ltle Sualtna River and 2lt •iloa of tr!butsry shelllll'l, including tfatane Creek. . 2) Nildllfl!l II>C/V tciuld 1noodate 12J ailea of critical winter rives Due to the lower potential for dltoct !~act: X a) Hoose bottOM habit.t. on 1100aa populaUoos •dthin the Sueltna, ~he W/OC plan is JUdged supsrlor-. W/DC wuld .inoodate 108 •Uea of this r-Iver bottOM h&il~tat. tllC/V !lllluld lnoodate. • large ar-aa upshe~~a of Vee utUized by three aub-populatlona of .:roso that range of large areas of the northeast e.acUon of the badn. W/DC \Cluld lntniate .the Wahna ~"k area ut.l.Uzed by .aoae. the condition of this aub-populaUoo of 11100se and the quality or the habit.at t.hay are using appeara to be deereuiog. - b) CarJbou The increased lBfiYlh _of' dvor-flooded, especially l.fl-Due to the potent lel for a ~rester Jillpuct on X atre011 frQIII the Vee dlllll alto, would result In the the Nelchlna car-Ibou herd• ha tllC/V echetle HDC/V plan creating a greater potential division or 1e tonaldered inferior. the Nelch!na herd~s rallgl!. In additlont an .lncraese . in range would be directly inundated by the Vee r~o- er-volr .. c) forbear-er-e ftta ar-ea flooded by the Vee reaervo.lr ls considere~ Due to the lesser-potential for-l~act on fur X iaportant to eo.e kel turbearer3, port!c~larly red fox bear-ers the N/DC ia Judged to be superior. lhJs area la judged o be .Ore J~~~porhnt than the Nab~na Cr-eek ar-aa that would be inmdated by the tt/DC plan. " d) iUrda and Bear-s roreot haoitat, hrportant for birds and besra 5 edata The HDC/V plan is judged superior. X aiong the Villley slope.a. lha loes of thle habll:al: would. be greater-with the ti/OC. plan .. . . Cultural There ia a high potential for d!acovery or llt'cheologi-The H/DC plso ia judued to have a lower po~ X cal aJten In lho easterly region of the uppe~ Susitna tentlal effect on archeological Bites. Baaln. Jhe li>C/V plan ha_s a greatel' potentlal·or affecting thaae sUes. for-other r-eaches of the dver- the dlfferenee between plana is conaldered minlanl• -•• ---- fABlE 11 ENVlRotH:NJAl EYALUAUON N' NAlAHA/OEVIl CANYOO Am ttlCII DEVIl CAN¥114/VE£ OCVEUlPHENt PlANS EnvironRentsl Attribute Aeathellc/ lend Use Plan C arison Nith eUiler schse, the aesthetic qtiiillly-of both Devil Canyon and Vee Canyon wuld be ir.palred. The HDC/Y plan .auld alao inundate. lausena ralls. Due to conslrue!lon at Vee na. site and the alzc of tho Vee Reservoi~, the HOC/V plen would. inherently crilate access to 110re wUdemeaa area ttlan wuld the W/DC plan. Doth pl&nB i;qlact tha valloy ~slht!Uca. 1he dl fference is a:maJdered •lniu~" A8 it la. ca$ler to extend acca&u lhlltl to !ltllit it, inherent ecceas requ,.rB1Mnh ~re conaldored detrlMntal lind the W/DC plan i:s judged superior. The ecalogical oenaltlvity of the arB& opened by ttlo lllC/V plAn ~ ln- forcea th.la judguent. Duo to the lower potential ror direct l~act on MOOse populat.iooa within the Sua!tna, the W/OC plan is judged sup: ?lor. OVERAll EVALUAJIOO; The W!DC plan ill judged to be superior to the lOC/V plcn. (rhe lottet t~~pact on birds and bears aanoclrted wlt.h tllC/V plan t.a canaldered to be outweighed by all the oUt!!r l~~pacts to'hich favour t.he li/DC pla.1.) NOTEt N : Matona 09lll OC. = Dev 11 Canyon Oa IOC = High Devil Canyoo Dnl: V = Vee 0811 -- X X I ' I I I - I I I I I I ' I I I I I ·1.·· .' I TABLE 12 ENERGY CONTRIBUTION EVALUATION OF THE WATANA/DEVIL CANYQN AND HIGH DEVIL CANYON/VEE PLANS Parameter Total Energy Production Capability Annual Average Energy GWH Firm Annual Energy GWH % Basin Potential Developed (1) Energy Potential Not Developed GWH (2) Watana/ Devil Canyon 6070 5520 91 60 High Devil Canyon/Vee 4910 3870 81 650 Remarks Watana/Devil Canyon plan annually devel- opes 1160 GWH and 16~0 GWH more average and firm energy re- pectively than the High Devil Canyon/Vee Plan. Watana/Devil Canyon plan develops more of the basin potential As currently con- ceived, the Watana/- Devil Canyon Plan does not develop 15 ft of gross head between the Watana site and the Devil Canyon reservoir. The High Devil Canyon/Vee Plan does not develop 175 ft gross head between Vee site and High Devil reservoir. Notes: (1) Based on annual average energy. Full potential based on USBR four dam scheme (Reference ). (2) Includes losses due to unutilized head. 1\io I I I I I ""' I I I I I t I, "" ,, I - I I I' 'it'~ I I ... TABLE 13. ~ OYERALL EVALUATION OF THE HIGH DEVIL CANYQN/YEE AND'WATANA/DEVIL CANYON DAM PlANS ATTRIBUTE ECONOMIC ENERGY CONTRIBUTION ENVIRONMENTAL SOCIAL OVERALL EVALUATION SUPERIOR PLAN WATANA/DEVIL CANYON WATANA/DEVIL CANYON WATANA/DEVIL CANYON WATANA/DEVIL CANYON (MARGINAL) PLAN WITH WATANA/DEVIL CANYON IS SUPERIOR TRADEOFFS MADE: NONE -•· -•• -., - TABLE 14 £COIQUC SENSITIVITY OF CQH>ARISOO OF GENERA WIN PLAN WI fll WAr ANA/DEVIl CAAYOO Af.O If£ All JUERHAl PLAN Present worth of lilt Benefit ($ Million) of total generation syste• coste for the Wahna/Devil Canyon plan over the all lhsr•al plan. t'arameters ECONDHIC EVAlUATiONJ Base Case SENSlllVIfY ANALYSES; Parameter Senaltivity Anaheea lOAD CROW!tl low U£ Low Hlqh CAPifAL COST ESTIHAI£ low Ther.al Coat• High ~droslectrlc Coat .. PERIOD Of EtONOHIC' ANALYSIS Period shortened to (1980 -2010) DlScoutU RAJE 5% a: (interpolated) ~ fUEl COSJ lowitiit FUEL COST ESCAtAUOH 0~ escalation for al fuels 0:!; escalation for coal only ECONmiC Tl!ERMAL PlA.~T sa: extension to all urr thermal plant life •lher11el capital cost decreooed by 22~ uaased on esUaated Sualtna coat plus Sot u•ruel Coats redUced by ZO: j>re~ wr!_n !I ~~l!lool ~I!IIBriCa Watana/DevU Canyon plan ~mre ecOOOMical than the all 2280 thar•al plan. 1280 thfi net benefit of the Wat.ann/Dillvl~ Canyon Plan re- 1570 •alns positive for the range of load forecasts con- 2840 aldered. 185(} Syate• coel:o relatively lnsonaUive. tapit:.al coal eetbsating t~rtalnty cbea not effect OCOOOIIlc 1320 . ranking. 2280 Shorter perlnd of evaluat.lon decreuoa. IK:onontic dlf- 960 ferencee. R&nfdnQ reae!nc l.li"clt&iitlOd. ~40 Below cUscoant. rate of BZ the lfatala/DeVll Canyon 0 phn is ecOflO&!cally euperlor. c -80 1810 200 ,, Watana/Oevil Canyon plan .reaalne econ<~~~icallr super- lor for wide range or fuel pdcoa !lld e!Deala ion rates. 1330 Econa.ic. benefit for Watana/Devll Canyon plan rele- 1800 tively insensitive to extended t.haraal plan econo.ic ure. - ---------..---.• -- Social Aspect Potential non-rene.wab 1 e resource dis- placement Impact on state economy Impact on local economy Seismic exposure Overa 11 Comparison TABLE 15 -Social Comparison of System Generation Plan with Watana/Oevil Canyon and the All Thermal Plan Parameter Million tons of Beluga coal, over 50 yeqr$ Direct & indirectl employment and income. Bustness invest-J ment. Risk of major structural failure Potential impact of failure on human 1 i fe Inconclusive All Thermal Generation Plan Gradually, continuously growing impact. Generation Plan with Watana/Devil Canyon 210 Potentially more disruptive impact on economics. All projects designed to similar levels of safety Failure would effect only operating personnel. Forecast of failure would be impossible Failure \'lould effect larger number of people located downstreams however, some degree of forecasting dam fa'ilure would be impossible Remarks With Watana/Dew'il Canyon plan is superior. ~I I I ~I I I I I I. I I I I I TABLE 16 GENERIC COMPARISON OF ENVIRONMENTAL IMPACTS OF A SUSITNA BASIN HYDRO DEVELOPMENT VERSUS COAL FIRED THERMAL GENERATION IN THE BELUGA COALFIELDS Environmental Attributes Ecological: Cultural: Aethetic/ Land Use: Concerns Susitna Basin D~velopment Poterttial impact on fisheries due to alteration of downstream flow distribution and water quality. Inundation of Moose and furbear habitat and potential impact on Caribou migration. No major air quality problems, only minor microclimatic changes would occur. Inundation of archeological sites. Inundation of large area and surface disturbance in construction area. Creates additional access to _, wilderness areas, reduces river recreation but increase!3 lake recreational activities. Thermal Generation Potential for impact on fisheries resulting from water quality impairment of local streams and local habitat des(ruction due to surface disturbances both at mine and generating facilities. Impaet on air quality due to emission of particulates SOz, NOx, trace metals and water vapours from generating facilities, Potential destruction of archeological sites. Surface disturbance of large areas associated with coal mining and thermal generation facilities. Creates additional access and may restrict land use activities. -~ I I -I I I ' I I· I I ,, I ' I I I I I I TABLE lT --OVERALL EVALUATION OF ALL THERMAL GENERATION PLANS WITH THE GENERATION PLAN INCORPORATING WAIANA/DEVIL CANYON DAMS ATTRIBUTE ECONOf~IC ENERGY CONTRIBUTION ENVIRONMENTAl SOCIAL 0Vb1ALL EVALUATION SUPERIOR PLAN WITH WATANA/DEVIL CANYON NO DIFFERENCE UNABLE TO DISTINGUISH DIFFERENCE IN THIS STUDY NO DIFFERENCE PLAN WITH WATANA/DEVIL CANYON IS SUPERIOR TRADEOFFS MADE: NOT FULLY EXPLORED ----.IIIII -- - -.. -.. ---_. --, TABLE I . SALIENT FEATURES OF GENERATION PLANNING PROGRAMS Program/ Developer GENOP/ Westinghouse PROMOO/EMA OGP/GE load Modeling Done by two external programs Done by one external program · Oone by one external program Generation Modeling Oone by one external program D01ne by one external program Oone by one e:>eternal program Opt imi zat ion Available yes no yes Re 1 i ab i 1 i ty Criterion LOLP or % reserve LOLP or % reserve LOLP or % reserve Production Availabilitl? and Simulation Cost/Run Deterministic or $500 to val!iidate Modified Booth -Learning Cu.nte Baleriaux Costs · SJoo -$so(}u~t•m Modified Booth -$2.,500 to ~·~lidate Baleriaux on TYMSHARE Learning CUf''f~ Costs $300 -$500/t""Un Deterministic or AAI validated Stochastic Columbia & Buffalo Experienced Personnel $50 -$800h"t.m I I I I I I I I I I I I ., I I I I I I TABLE z. -"- LOAD AND ENERGY FORECASTS* ALASKA RAILBELT AREA Low Forecast Mid Forecast Hi2h Forecast YEAR MW GWh MW ~Wh -MW . ~~Fi 1980 BASE 514 2,789 514 2,789 514 21t789 1985 578 3,158 650 3,565 695 3~859 1990 641 3,503 735 4,032 920 5,085 1995 797 4,351 944 5,171 1,294 7,119 2000 952 5,198 1,173 6,413 < 1, 669 9,153 2005 1,047 5,707 1,379 7,526 2,287 12,543 2010 1,141 6,215 1,635 8,938 2,209 15,933 * Derived from the Woodward-Clyde Consultants submittal of September 23, 1980, adjusted to e1 iminate industrial self-supplied and two-thirds of the military sector. I I I I I I I I I I I I I I I I I I I TABLE . 3 ANNUAL FIXED CARRYING CHARGES USto IN GENERATION PLANNING MODEL - 30oYear Thermal (%) ECONOMIC PARAMETERS (0%-3%) Cost of ~ney Amortization Insurance TOTALS 3.00 2.10 0.25 5.3"5" 35-Year SO-Year Thermal Hydro {%) (%) 3.00 1.65 0.25 4.90 3.00 0.89 0.10 3.99 2o-Year · Thermal (%) 3.00 3~72 0.25 6.97 ~ I I I I I I I I I· I I I I I I I I I ~I TABLE . 4 · FUEL PRICES AND ESCALATION RATES Base Period (January 1980) Prices ($/million Btu) Market Prices Shadow (Opportunity} Vajues Real Escalation Rates (Percentage Change Compounded Annually) 1980 -1985 1986 -1990 1991 -1995 Composite (average) 1980 -1995 1996 -2005 2006 -2010 Natural Gas Coal Distillate ~ $1.05 $1.15 $4.00 2.00 1.15 4.00 1.79% 9.56% 3 .. 38% 6.20 2 .. 39 3.09 3.99 -2.87 4 .. 27 3.98 2.93 3.58 3.98 2.93 3.58 0 0 0 I I I I I I I I I I I I I I I I •• I I TABLE S' . --. SUMMARY OF ECONOMIC PARAMETERS FOR GENERATION PLANNING 1 _, .Base Period (January 1980) Energy Prices ( $/mi 11 ion Btu) 1.1 -Natural Gas 1.2 -Coal 1.3 -Distillate 2.00 1.15 4.00 2 -General Price Inflation Per Year (X) not applicable 3 -Discount & Interest Rates Per Y.ear 3.1 -Real Discount Rate 3. 2 -Nominal Interest Rate (Non-exempt Case) 3.3 -Nominal Interest Rate (Tax-exempt Case) 4 -Non-energy Cost Escalation Per Year (%) (%) 3 not applicable not app 1 icab 1 e 0 5 -Ene~y Price Escalation Per ~ar (%) 5.1 -Natural Gas 1980 -2005 3.98 2006 -2010 0 5.2 -Coal 1980 -2005 2.93 2006 -2010 0 5.3-Distillate 1980 -2005 3.58 2006 -2010 0 6 -Economic life (Years) 6.1 -Large Steam Turbine 6.2 -Small Steam Turbine 6.3 -Hydro 6.4 -Diesel and Gas Turbine (Gas-fired) 6. 5 -Gas Turbine ( Oi 1-fired) 30 35 50 30 20 ~ I ,. I TABLE b TEN YEAR BASE GENERATION PLAN MID LOAD FORECAST I SYSTEM (MW} TOTAL YEAR MW MW NG OIL OIL CAPABILITY Conmitted Retired COAL GT GT DIESEL cc HY (MW) I 1980 54 470 168 65 141 49 947* I 1Q~1 -----54 470 . 168 65 141 49 947 1982 60 cc 54 470 168. 65 201 49 1007 I 1983 -54 470 168 65 201 49 1007 I 1984 54 470 168 65 201 49 1007 1985 14 (NGGT) 54 456 168 65 201 49 993 I 1986 -50 456 168 65 201 49 993 1987 4 (Coal) 50 456 168 65 201 49 989 I 1988 95 HY 50 456 168 65 201 144 1084 I 1989 5 (Coal) 45 456 168 65 201 144 1079 1990 45 456 168 65 201 144 1079 I •• *This figures varies slightly from the 943.6 MW reported due to internal computer rounding • I ~ I I I I :J) . I I ----------.. ------; .,. TABLE 7 SUSITNA BASIN HYDROELECTRIC ALTERNATIVES ' Construction ~ak ftbnth On-line Period Total Cost* Installed Firm Plan Stage Description Month/Year (Yrs) Million 1980$ Capacity Capacity ,. I 1 Watana Low Dam .1/92 8 1774 400 MW 206 MW El.2. 2 Raise Watana Dam 1/95 3 376 194 MW 3 Add Capacity 1/97 3 136 400 MW 400 MW 4 Devil Canyon Dam 1/02 7 999 400 MW 352 MW TOTAL 1200 MW 1152 ~tw 1 High Watana Dam 6/93 9 1984 400 MW 400 MW ~·~3 2 Add powerhouse capacity 1/96 3 157 400 MW 400 MW 3 Devil Canyon 0&~ 1/00 7 999 400 MW 352 '*' TOTAL !~00 MW 1152 MW 1 Watana High Oam 6/93 9 1984 400 MW 400 MW l Oevil Canyon Dam 1/00 7 999 4oo·Mw 337 MW TOTAl BOO MW .... 737 M4 1 High Devil Canyon Dam 1/94 8 1570 400 MW 351 MW -2 Vee Oam 1/00 7 1177 400 MW 315 MW TOTAL SOO MW ... 666 MW 1 Watana High Dam 6/93 9 1984 400 MW 400 MW I· s-2 Add powerhouse capacity 1/96 3 157 400 MW 400 MW 3 Add tunnel capacity 1/00 5 tc.~~ 380 MW lft4 t1W TOTAL 1180 MW 'tqf MW Comp. 1 Chakachamna 1/93 10 . 1201 500 MW 500 MW Hydro 2 Keetna 1/97 8 463 120 MW 77 MW 3 Snow 1/02 6 223 . 50 MW 22 MW TOTAl 670 MW b99 MW *Includes Interest During Construction (IDC) B"'-+ e.>=ctw?Les.. rest e>f le.~e.JtA...lctt~'oL\ do"""s. t-+ f wo +u't~e.( s~~e£4..,(. .. - - . --II I ---------·----~-· ' TABLE B SUMMARY OF BASE GENERATION PLANS -MID LOAD FORECAST -1200MW SUSITNA ALTERNATI\tttS PARAMETER I JOB 1.0.1 1990 Jt"tl 1990-2010 THERMAL AODS: Co a 1 {MW) NGGT (MW) Diesels (MW) TOTAL RETIREMENTS (MW) HVORO ADDS: MONTH/YEAR NAME MW TOTAL FIRM* (2010) $ X 106 (80$) 10 Year PW 20 Year PW TOTAL LONG TERM {2040) PW *In Peak Month (December) •~~< \tvo fttl.\'fe,( s-chev..e. W/DC t.2 l5Y9 1079 M\4 200 300 0 500 MW (734) 1/92 W400 1/95 + Dam 1/97 W400 1/02 OC400 1997 MW $ 873.7 2509.4 $3383.1 $6028 SUSITNA ALTERNATIVES W/DC HOC/VEE HDC/CC wnr•~ EJ .. ~ E2·~ il-:s l8J9 L601 LEB3 .,\:..*D'I 1079 MW 1079 MW 1079 MW 101/~ MW 300 300 300 ~n 225 450 525 ~(} 0 20 220 ~ -.-- 525 MW 770 M\4 1045 MW 600 MW (734) (734) (734) (1'1/li) 6/93 W400 6/93 HDC400 6/93 HDC400 6/93 W400 1/96 W400 1/96 HDC400 1/96 HOC400 1/9~ 'W400 1/00 DC400 l/00 VEE400 1/00 CC500 1/00 T380 2023 MW 2230 MW 2690 MW 2034 MW '$ 873.7 $ 873.7 $ 873.7 $ 873.7 2360.6 2487 .. 8 2624.5 2591.0 $3234.3 $3361.5 $3273.2 $3464.7 $5851 $6372 $6209 $6528 . - -------------------1 0 TABLE 9 PARAMETERS I JOB I.O.# 1990 MW 1990-2010 THERMAL ADDS: Coal (MW) NGGT (MW) Die-sels (MW) TOTAL RETIREMENTS (MW) HYDRO ADDS: MONTH/YEAR NAME MW TOTAL FIRM* .Mil(?olO) $ X 106 (80$) 10 year PW 20 year PW TOTAl LONG TERM (2040) PW * In peak month -December t;u~ '"T""" SUMMARY OF GENERATION PLANS -MID LOAU FORECAST -800 MWJALTERNATIVES WBOO -L7W7 1079 MW 50"0 450 950 MW (734) 6/93 W400 1/96 W400 2095 MW $ 87347 2765.1 $ 3638.8 $ 6955 SUSITNA ALTERNATIVES HOC800 W400/DC400 LE07 1079 MW 500 450 30 LCK5 1079 MW 200 525 50 980 MW 775 MW (734} (734) 6/93 HDC400 6/93 W400 1/96 HDC400 1/00 OC400 2125 MW 1858 MW $ 873.7 $ 873.7 2628.0 2349.6 $ 3501.7 $ 3223.3 $ 6715 s 5891 HDC/V~~ LB25, 4001 450 60· 910 HW (734} 1/94 HOC 400 1/00 VEE 400 1921 NW $ 873-.7 2624.5 $ 3498 .. 2 $ 6620 -- - --- - - - - - - - - - --l --·0 I .r ~ Aa..T&#Wt:\"~'"'e TABLE ... 10 ·_ SUMMARY OF ..BASE GENERATION PLANS -MID lOAO FORECAST PARAMETER I JOB I.D.# 1990 MW 1990-2010 THERMAL ADOS: Co a 1 (MW) NGGT (MW} Diesels (MW) TOTAL RETIREMENTS (MW) HYDRO ADOS: MONTH/YEAR NAME MW TOTAL FIRM* MW~OlO) $ X 106~60$) lo Year 20 Year PW TOTAL LONG TERM (2040) PW *In Peak Month (December) **RN -renews THERMAL THERMAL ANO RENEWS NO RENEWS OTHER HYDRO LME3 LMEl lfl7 1079 MW 1079 MW 1079 MW 456 RN** 900 900 700 150 600 300 40 50 10 1546 MW 1550 MW 1010 MW (734) (734) (734) 1/93 Chak a 500 1/97 Keetna 120 1/02 Snow 50 1891 MW 1895 MW 1954 MW $ 873.7 $ 873.7 $ 873.7 3308.3 3319.4 2802.2 $4182.0 . $4193.1 $3675.9 $8109 $8133 $7038 ~de=/ ~ ' - - --' - - - - - - - - - - -----~· TABLE II PARAMETER I JOB 1.0.# 1990 MW (+100 MW COAl} 1990-2010 THERMAl ADDS: Coal (MW) NGGT (MW) Diesels (MW) TOTAL RETIREMENTS (MW) HYDRO ADOS: MONTH/YEAR NAME MW TOTAL FIRM* .H({2010) $ x 106 J80$) 10 year PW 20 year PW TOTAl lONG TERM {2040) PW *In peak month -December ~ SUMMARY· OF SUSITNA GENERATION PlANS -HIGH lOAD FORECAST SUSITNA AlTERNATIVES 3AE HOC/VEE HDC/VEE/CC W/W/OC/ert LA73 LBV3 l8Yl lBV7 1179 MW 1179 MW 1179 MW 1179 MW 900 1200 900 700 750 750 675 450 90 10 60 1650 MW 2040 MW 1585 MW 1210 MW (734) (734) (734) '( 734) 6/93 W400 6/93 HDC4UO 6/93 HDC400 6/93 W4Utl 1/96 W400 1/96 HOC400 1/96 HDC400 1/96 W4QO 1/00 OC400 1/00 VE£400 1/00 VEE400 1/00 OC4QO 1/03 CC500 1/05 ccsoo 3248 MW 3600 MW 3645 MW 3308 MW / ' . $ 1060.5 $ 1060.5 $ 1060.5 $ 1060.5 4094.6 4462.4 4252.9 3946.3 $ 5155.1 $ 5522.9 $ 5313.4 $ 5006.8 . $10,678 $11,719 $11,037 $10,048 - - - --- - - - - - -Ill - - - - - -'' TABLE 12 PARAMETER I JOB I.D. I 1990 MW 1990-2010 THERMAL ADOS: Coal {MW) NGGT (MW) Diesels (MW) TOTAL RETIREMENTS {MW) HYDRO ADOS: MONTH/YEAR NAME MW TOTAL FIRM* (2010) $ X 106 (80$) lO year PW 20 year PW TOTAL LONG TERM (2040) PW *In peak month -December ~¥-"(t.XJ +u.\IL"d s~~e.~e SUMMARY OF SUSITNA GENERATION PLANS -LOW lOAD FORECAST SUSIT.NA ALTERNATIVES W400/0C400 HDC/VEE HOC400 W400-W400;7f ~-ie lC07 LGO '!-lBUl LBK7 l600 l079MW 1079M~I 1079MW 1079MW 1019MW 100 400 200 150 225 300 300 31S 40 30 80 00 - 190MW 355MW 700MW 58()Mlri 39-~W {734) (734) (734) -(734) (71-) 6/93 W400 6/93 HOC400 6/93 HOC400 6/93 W400 6/93 \>1400 1/02 OC400 1/02 VEE400 1/02 T3BO . 1272MW 1367MW 1396MW l325MW l319MW $ 744.1 $ 744.1 $ 744.1 $ 744.1 $ 744~1 1835.8 1894.9 1961.6 2029.7 2048 .. 5 -· $ 2579.9 $ 2639.0 $2705.7 $2773.8 $2792.6 $ 4350 $ 4557 $4852 $4940 $4997 I I I I I I I I I 8 • I I I I I I I I I SUMMARY OF GENERATION PLANS -LOAD M4NAGEMENT AND CONSERVATION PARAMETER I JOB I.O.# 0 1990 MW 1990-2010 THERMAL ADDS: Coal {MW) ·· NGGT (MW) Diese 1 s { MW) TOTAL RETIREMENTS ( MW) HYDRO ADOS: MONTH/YEAR NAME MW TOTAL FIRM* MW 2010 $ X 106 (80$) lo year"" PW 20 year PW TOTAL LONG TERM (2040) PW *In peak month -December THERMAL No RENEWS' LBT7 1079 MW 500 225 90 -815 MW (734) 1160 MW $ 721.9 2034.3 $ 2756.2 $ 4931 SUSITNA ;;~~~~~400 1079 MW -450 50 500 MW (734) 1/97 W400 1/05 DC400 1582 MW $ 721.9 1556 .. 0 $ 2277.9 $ 3648 - I I~ I I I I I I I I I ~• I I .. I I I. TABLE . Jtfr. SUMMARY OF GENERATION PLANS -PROBABILISTIC LOAD FORECAST THERMAL SUSITNA NO RENEW$' -· 3AE PARAMETER l JOB I .D.# LOF3 L8T5 ------~------------------~--~--~---~----------~~--- 1990 MW 1079 MW 1990-2010 THERMAL ADDS: Coal (MW) NGGT (MW) Diesels (MW) TOTAL RETIREMENTS {MW) HYDRO ADDS: MONTH/YEAR NAME MW TOTAL FIRM* MW 2010 $ X 106 (80$~ lo year PW 20 year PW TOTAL LONG TERM (2040) PW *In peak month -December 1100 1575 100 2775 MW (734) 3120 MW $ 873.7 3353.6 $4227.3 $8324 1079 MW 200 1275 140 1615 MW (734) 6/93 W400 1/96 W400 1/02 DC400 3112 MW $ 873.7 2546.5 $3420.2 $6292 -- I I I I I I I 1: -• I I I I. I I I I I I TABLE 15 INPUT PARAMETERS -INTEREST RATE SENSITIVITY Input Variable Annual Fixed Carrying Charg~ {%) 30 Year Therma 1 20 Year Therma 1 50 Year Hydro Total Capita1 Costs 250 MW Coal 75 MW ~GGT 10 MW Otesel 1 -Watana 400 2 -Watana 400·· ($ X 106) 3 -Devil Canyon 400 3 Percent 5.35% 6 .. 97 3.99 $ 686 26 10 $ 1984 157 999 Interest Rates 5 Percent 6.75% 8.27 5.58 $ i2i 26.3 10.3 $ 2175 161 1069 9 Percent 9.98% 11.20 9.37 $ 815 27 10.4 $ 2589 168 1224 .. -.. ---...... - --.. -- - -·---16 TABLE 16 SENSIT!VlTY ANALYSiS • iNTEREST RATES THERMAL BASECASE SENSITIVITY PARAMETER I JOB 1.0.1 lMEl LEA9 LEBl ESCALATION/ INTEREST RATE 0% -3% 0% -5% 0% -9% 1990-2010 THERMAl ADOS: Coal {MW) 900 900 900 NGGT (~1W) 600 600 600 Diese 1 s { MW) 50 50 50 TOTAL 1550 MW 1550 MW 1550 MW RETIREMENTS (MW) (734) {734} ( 734) HYDRO ADOS: MONTH/YEAR NAME MW TOTAL FIRM* MW 2010 1895 K.J 1895MW 1895 MW $ X 106 (80$) 10 Year 'PW $ 873.7 $ 791.1 $ 714.8 20 Year PW 3319.4 2441.7 1367.2 TOTAL $4193 .. 1 $3232.8, $2082.0 LONG TERM (2040) PW $8133 $5172 $2609 *In Peak Month (December) BASECASE l8J9 0% -3% 300 225 525 MW (734) 6/93 W400 1/96 W400 1/00 OC400 2023 MW $ 873.7 2360.6 $3234.3 $5851 SUSlTNA -3AE SENSITIVITY lf85 lf87 0% -5% 0% -9% 300 300 225 225 525 MW 525 MW (734) (734) 6/93 W400 6/93 W400 1/96 W400 l/96 W400 1/00 OC400 1/00 OC400 2023 MW 2023 K4 s 791.1 $ 714.8 1977.3 1469.2 $2768.4 $2184.0 $4226 $2691 :" I I I .I I· I I I I I I I I I I I I· I I TABLE 17 . SENSITIVITY ANALYSIS .. FUEL COSTS THERMAL SUSITNA -3AE BASECASE<> -.SENS l Tl vTFY BAStCASE SENSITIVITY PARAMETER I JOB ! .. 0.# LMEl LlK7 L8J9 L533 FUEL COST {$/MMBTU) Coal $1.15 $0 .. 92 $1.15 $0.92 Natural Gas $2.00 $1.60 $2.00 $1 .. 60 Oil $4.00 $3.20 $4.00 $3.20 1990-2010 THE~~L ADDS: Ccal (MW) 900 800 300 100 NGGT {MW) 600 675 225 375 Diesels { ft1W) 50 70 20 --TOTAL 1550 MW 1545 MW· 525 MW 495 MW RETIREMENTS (MW) (734) (734) {734) (734) HYDRO ADOS: MONTH/YEAR NAME MW 6/93 W400 6/93 W400 1/96 W400 1/96 W400 1/00 DC400 1/00 OC400 TOTAL FIRM* MW 2010 1895 MW 1890 MW 2023 MW 1993 M;l $ X 106 (80$) Io year PW $ 873.7 $ 716.5 s 873:7 $ 716.5 20 year PW 3319.4 2880.0 2360.6 2145.2 -TOTAL $4193.1 $3596.5 $3234.3 $2861.7 LONG TERM (2040) PW $8133 $7072 $5851 $5260 * In Peak MJnth (December) NOTE: Sensitivity analysis performed using 0~ escalation, 3% interest rate and the midload forecast. --... -.. ----· ·-----' .. -.. ---·8 TABLE : 18 SENSITIVITY ANALYSIS -FUEL COST ESCALATION THERMAl BASECASE SENSITIVITY PARAMETER I JOB I. 0.# lMEl l547 l561 FUEL COST ESCALATION RATES (%) Natural Gas 3.98% 0% 3.98% Coal 2.93% 0% 0% Oil 3.58% 0% 3.58% 1990-2010 THERMAL ADDS: Coal" (f*l} ''900 1100 NGGT (MW) 600 1500 525 Diesels {MW) 50 10 10 "TOTAL 1550 MW 1510 MW 1635 MW RETIREMENTS (MW) (734) {734) ( 734) HYDRO ADDS: MONTH/YEAR NAME MW TOTAL FIRM* MW 2010 1895 MW 1855 MW 1980 ~1W $ x 106 j80$} lo year PW $ 873.7 $ 721.8 $ 865.4 20 year PW 3319.4 1835.0 2854.6 TOTAL $4193.1 $2556.8 $3720.0 LONG TERM {2040) PW $8133 $4558 $6916 * ln Peak f.bnth (December) BASECASE L8J9 3.98% 2.93% 3.58% 300 225 525 MW ( 734) 6/93 W400 1/96 W400 1/00 OC400 2023 MW $ 873.7 2360.6 $3234.3 $5851 SUSITNA -3AE SENSITIVITY L557 t$63 0% lL.~8% 0% 0% 0% 3t.5B% 3100 450 tf~5 30 ' .... 480 MW $25 MW ( 734) €7734) 6/93 W400 6/93 W400 1/96 W400 1/96 W400 1/00 OC400 l/00 OC400 1978 MW 2023 i4l $ 721.8 $ 855o4 1806.4 23'07.1 $2528.2 $3172.5 $4357 $5586 NOTE: Sensitivity analysis performed using 0% escalation, 3% interest rate and the mid load forecast. ·~ -I I I I I I I I I I I I I I I I I I I TABLE _· ......:....o:;/9.__~5-EN.;..;;;S..;;;.I T.;..;;I;..;.V.;..IT_Y...;A..;.;.N;;.;.,;,AL~Y;..;;;.S.;.;I S;;;.._-...:T;.;.;H~ER~MA~L;;_,;,..P.;;;;;;.LA..;.;.;N~T..;.R,;.;:.ET..:..;:I;;.;.;;R.;;;.;.EM..;.;:E;.;.;.NT.,;,_,;_P,;;.;OL::.:::!..::;..;..CY PARAMETER I JOB I.O.# RETIREMENT POLICY (YRS.) Coal-fired Steam Natural Gas GT Oil GT 1990-2010 THERMAL ADOS: Coal (MW) NGGT (MW} Dies~ 1 s ( r.1W} TOTAL RETIREMENTS {MW) HYDRO ADOS: MONTH/YEAR NAME MW TOTAL FIRM* MW 2010 $ X 106 (80$) 10 year PW 20 year PW TOTAL LONG TERM (2040) PW * ln Peak f.bnth (December) THERMAL BASECASE SENSITIVITY LMEl L583 30 Yrs 30 Yrs 20 Yrs 900 600 50 1550 MW (734) 1895 MW $ 873.7 3319.4 $4193.1 $8133 45 Yrs 45 Yrs 30 Yrs 1100 75 1175 MW (290) ,, 1973 MW $ 873.7 3318 .. 3 $4192.0 $7850 SUS!TNA -3AE BASECASE SENSITIVITY L8J9 L585 30 Yrs 30 Yrs 20 Yrs 300 225 525 MW (734) 6/93 W400 1/96 W400 1/00 DC400 2023 MW $ 873·. 7 2360.6 $3234 .. 3 $5851 45 Yrs 45 Yrs 30 Yrs OMW (290) 6/93 W400 1/96 W400 1/00 OC400 1951 tiM' $ 873.7 2382.7 $3256.4 $6100 NOTE: Sensitivity analysis performed using 0% escalations 3% interest rate and the midload forecast. --------·-----------Zo TAB~E . 20 SENSITIVITY ANALYSIS -THERMAL PLANT CAPITAl COSTS (1980$~ .. .. THERMAL SUSITNA -3AE BASECASE SENSITIVITY BASECASE SENSITIVITY PARAMETER I JOB L 0.# lMEl lAL9 l8J9 LED7 THERMAL PLANT CAPITAl COSTS (S/kW) Coal-fired Steam (250 MW) $2744/kw 1 S2135/kw 2 S2744/kw 1 S2IJ5/kw 2 Natural Gas GT {75 MW) 350/kW 350/kW 350/kW 350/kW Diesels (10 MW) 778/kW 778/kW 778/kW 778/kW 1990-2010 THER~~l ADDS: Coal (MW) 900 1100 300 300 NGGT (MW) ·600 525 225 225 Diesels (MW) 50 10 TOTAl 1550 MW 1635 MW 525 MW 525 MW RETIREMENTS (MW) (734) (734) (734) ( 734) HYDRO ADOS: MONTH/YEAR NAME MW 6/93 W400 6/93 W400 1/96 W400 1/96 W400 1/00 DC400 1/00 OC400 TOTAL FIRM* MW 2010 1895 MW 1980 MW 2023 NW 2023 MW _$ x 10° (80S)_ lo year PlY s 873.7 $ 873.7 $ 873.7 $ 873.7 20 year .PW 3319.A 3095.3 2360.6 2344.6 -· TOTAL $4193.1 $3969.0 $3234.3 $3218.3 lONG TERM (2040) PW $8133 '$1585 $5851 $5744 *In Peak Mbnth (December} NOTE: Sensitivity analysis performed using 0% excal at ion, 3% interest rate and the mfd load forecast. ·· · lt ,a A1 ask an Adjustment Factor 2t.4 Alaskan Adjustment factor ----- ---- - - - - - --WATA~A/ bE\IIL C.lt~Yof\1 TABLE 2/ SENSITIVITY _ANALYSIS -CAPITAL COSTS (1980$)_ - PARAMETER I JOB I.D.# SUSITNA COST ($xl06) (80$) Watana Dam Devil Canyon Dam Tunnel 1990-2010 THER~1AL ADDS: Co a 1 (r.M) NGGT (MW) Diesels {MW) TOTAl RETIREMENTS (MW} HYDRO ADOS: MONTH/YEAR NAME MW TOTAl FIRM* MW 2010 $ X 106 {80$) ·1o year PW 20 year PW . TOTAL LONG TERM (2040) PW *In Peak Month (December) TU\SECASE l8J9 $1984 999 300 225 525 MW ( 734) 6/93 W400 1/96 W400 1/00 OC400- 2023 MW $ 873.7 2360.6 $3234.3 $5851· SUSITNA - SENSITIVITY l5Gl L075 $1984 $2976 1110 1498 300 300 225 225 525 MW. 525 MW (734) (734) 6/93 W400 6/93 W400 1/96 W400 1/96 W400 1/00 OC400 2023 MW 2023 MW $ 873.7 $ 873.7 2546.2 2836.3 $3419.9 $3710.0 $6212 $6807 NOTE: Sensitivity analysis performed using 0% escalation, 3% interest rate and the mid load forecast. -2· - - - - - - -.. - -.. - - - - - - --·~ PARAMETER I JOB 1.0.# 1990 MW 1990-2010 THERMAL AODS: Coal {MW) NGGT (MW} Oi esel s (MW) TOTAL RETIREMENTS {Ml4) HYDRO AODS: MONTH/YEAR NAME MW TOTAL FIRM* (2010) $ X 106 (80$) lO Year PW 20 Year PW TOTAL LONG TERM (2040) PW *In Peak Month (December} WAT1rNA/ TABLE 2-2.. SENSITIVITY ANAlYSIS -TUNNEl CAPITAl COSTS 1\ . • " l ' • TUNNEl COST HALVED • MEDIUM LOAD W/T 1:1$ l615 1079 MW 200 450 30 580 MW (734) 6/93 W400 1/96 ~1400 1/00 T $ 873.7 2¢74.2 - $3347.9 $6232 TUNNEl COST HAL VEO -lOW lOAD W/T t.s l613 1079 MW 375 20 395 MW (734) 6/93 W400 1/02 T $ 744.1 1955.8 $2699.9 $4726 I)