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HomeMy WebLinkAboutAPA356aAlaskaResourcesLibrary&InformationSerVicesAnchorage,Alaska DATEDUEI'<l.f';uA""1t,;5)JAIillV""~1111no'1"........n,",UL-r--Z;UlJJiiiiHIGHSMITH45-220 ACRESAMERICANINCORPORATED1577CStreetSuite305Anchorage,Alaska99501Telephone:(907)279-9631TKt4;lSALASKAPOvlERAUTHORITYSUSITNAHYDROELECTRICPROJECTTASK6 -DEVELOPMENTSELECTIONSUBTASK6.05DEVELOPMENTSELECTIONREPORTAPPENDICESATHROUGHJDECEMBER1981ACRESAMERICANINCORPORATED1000LibertyBankBuildingMainatCourtBuffalo,NewYork14202Telephone:(716)853-7525 ALASKAPOWERAUTHORITYSUSITNAHYDROELECTRICPROJECTSUSITNABASINDEVELOPMENTSELECTIONVOLUMEII-APPENDICESATHROUGHJTABLEOFCONTENTSLISTOFTABLESiiiLISTOFFIGURESviiiA-GENERICPLANFORMULATIONANDSELECTIONMETHODOLOGYA.1-PlanFormulationandSelectionMethodologyA-2A.2-GuidelinesforEstablishingScreeningandEvaluationCriteriaA-2A.3-PlanSelectionProcedureA-5B -THERMALGENERATINGRESOURCESB.1-FuelAvailabilityandCostsB-1B.2-ThermalGeneratingOptions-CharacteristicsandCostsB-7B.3-EnvironmentalConsiderationsB-16C -ALTERNATIVEHYDROGENERATINGSOURCESC.1-AssessmentofHydroAlternativesC-1C.2-ScreeningofCandidateSitesC-1D-ENGINEERINGLAYOUTDESIGNASSUMPTIONSD.1-ApproachtoProjectDefinitionStudiesD-1D.2-ElectricalSystemConsiderationsD-1D.3-GeotechnicalConsiderationsD-2D.4-HydrologicandHydraulicConsiderationsD-3D.5-EngineeringLayoutConsiderationsD-3D.6-MechanicalEquipmentD-3D.7-ElectricalEquipmentD-40.8-EnvironmentalConsiderationsD-4E -SUSITNABASINSCREENINGMODELE.1-ScreeningModelE-1E.2-ModelComponentsE-2E.3-ApplicationoftheScreeningModelE-3E.4-InputDataE-3E.5-ModelRunsandResultsE-4i ALASKAPOWERAUTHORITYSUSITNAHYDROELECTRICPROJECTSUSITNABASINDEVELOPMENTSELECTIONVOLUMEII-APPENDICESATHROUGHJTABLEOFCONTENTS(Cont'd.)F -SINGLEANDMULTI-RESERVOIRHYDROPOWERSIMULATIONSTUDIESF.l-IntroductionF-lF.2-SingleReservoirModel•.....•............................F-lF.3-Multi-ReservoirSimulation........•..................•.•.F-3F.4-AnnualDemandFactorF-3F.5-InputtoSimulationModelsF-4F.6-ModelResultsF-5F.7-InteractionofOGP5F-6G-SYSTEMWIDEECONOMICEVALUATIONG.l-Introduction..•....•.....................................G-lG.2-GenerationPlanningModelsG-2G.3-GenerationPlanningResults...........................•..G-8H-ENGINEERINGSTUDIESH.1-Dev;1CanyonSiteH-lH.2-WatanaSiteH-5I -ENVIRONMENTALSTUDIES1.1-Summary.......................•..........................I-I1.2-TESReport1-3J -AGENCYANDOTHERCOMMENTSJ.l-ResponsestoAEIDCComments•..•......•...................J-lJ.2-ResponsestoADF&GComments..............•...............J-2J.3-ResponsetoUSGSCommentsJ-2J.4-ResponsetoUSNPSCommentsJ-2J.5-ResponsetoADECComments............•...................J-2; ; LISTOFTABLESA.lA.2A.3A.4B.lB.2B.3B.4B.5B.6B.7B.8B.9B.10B.11B.12B.13B.14B.15C.lC.2Step2 -SelectCandidatesStep3 -Screening ProcessStep5 -PlanEvaluationandSelectionExamplesofPlanFormulationandSelectionMethodologyAlaskanRailbeltCoalDataAlaskanGasFieldsAlaskanOilFieldsAlaskanRailbeltFuelPrices(1980)SummaryofAlaskanFuelOpportunityValuesGeneratingUnitsWithintheRailbelt-1980ExistingGeneratingCapacityintheRailbeltRegion1000MWCoal-FiredSteamPlantCostEstimate-Lower48500MWCoalFiredSteamCostEstimates250MWCoal-FiredSteamCostEstimates100MWCoal-FiredSteamCostEstimates250MWCombinedCyclePlantCostEstimatesSummaryofThermalGeneratingResourcePlantParamatersGasTurbineTurnkeyCostEstimateGas75MWGasTurbineCostEstimateSummaryofResultsofScreeningProcessSitesEliminatedinSecondIterationiii LISTOFTABLES(Cont.)C.3C.4C.5C.6C.7C.8C.9C.10C.llC.12C.l3C.14C.15C.16C.17C.18C.19C.20C.210.10.20.3EvaluationCirteriaSensitivityScalingSensitivityScalingofEvaluationCriteriaSiteEvaluationsSiteEvaluationMatrixCriteriaWeightAdjustmentsSiteCapacityGroupsRankingResultsShortlistedSitesPreliminaryCostEstimate-SnowPreliminaryCostEstimate-KeetnaPreliminaryCostEstimate-CachePreliminaryCostEstimate-BrownePreliminaryCostEstimate-Talkeetna- 2PreliminaryCostEstimate-HicksPreliminaryCostEstimate-ChakachamnaOperatingandEconomicParametersforSelectedHydroelectricPlantsAlternativeHydroDevelopmentPlansResultsofEconomicAnalysesofAlternativeGenerationScenariosMonthlyVariationsofEnergyandPeakPowerDemandGeotechnicalDesignConsiderationsInitialHydrologicDesignConsiderationsiv LISTOFTABLES(Cont.)0.40.50.60.70.80.90.10E.lE.2E.3E.4E.5E.6E.7E.8F.lF.2F.3F.4F.5F.6F.7RevisedDesignFloodFlowsforCombinedDevelopmentSiteSpecificHydraulicDesignConsiderationsGeneralHydraulicDesignConsiderationsPreliminaryFreeboardRequirementExampleCalculationofFreeboardRequirementatDevilCanyonEngineeringLayoutConsiderationsasSingleDevelopmentsTentativeEnvironmentalFlowConstraintsComputedStreamflowatDevilCanyonComputedStreamflowatHighDevilCanyonComputedStreamflowatWatanaComputedStreamflowatSusitna3ComputedStreamflowatVeeComputedStreamflowatMaclarenComputedStreamflowatDenaliResultsofScreeningModelReservoirandFlowConstraintsDamSiteStreamflowRelationshipSusitnaDevelopmentPlansSusitnaEnvironmentalDevelopmentPlansPlan1.1-EnergiesPlan1.2-EnergiesPlan1.3-Energiesv LISTOFTABLES(Cont.)F.8F.9F.10F.llF.12F.13F.14F.15G.lG.2G.3G.4G.5G.6G.?G.8G.gG.10Plan2.1-EnergiesPlan2.2-EnergiesPlans2.3andE.213-EnergiesPlan3.1-EnergiesPlan4,1-EnergiesPlanEl.2-EnergiesPlanEl.3-EnergiesPlanE2.4-EnergiesSalientFeaturesofGenerationPlanningProgramsRailbeltRegionLoadandEnergyForecastsUsedForGenerationPlanningStudiesLoadsandProbabilitiesUsedinGenerationPlanningFuelCostsandEscalationRatesAnnualFixedCarryingChargesUsedinGenerationPlanningModelTenYearBaseGenerationPlanMediumLoadForecast.SusitnaEnvironmentalDevelopmentPlansResultsofEconomicAnalysesofSusitnaPlans-MediumLoadForecastResultsofEconomicAnalysesofSusitnaPlans-LowandHighLoadForecastsResultsofEconomicSensitivityAnalysesforGenerationScenarioIncorporatingSusitnaBasinDevelopmentPlanEl.3-MediumForecastvi LISTOFTABLES(Cont.)G.llG.12I.lI.2I.3ResultsofEconomicAnalysesofAlternativeGenerationScenariosResultsofEconomicAnalysesforGenerationScenarioIncorporatingThermalDevelopmentPlan-MediumForecastEnvironmentalEvaluationofDevilCanyonDamandTunnelSchemeSocialEvaluationofSusitnaBasinDevelopmentSchemes/Plans.EnvironmentalEvaluationofWatana/DevilCanyonandHighDevilCanyon/VeeDevelopmentPlansvii LISTOFFIGURESA.lC.1C.2C.3C.4C.5C.6C.7C.8C.9C.10C.11LlL2L3L4F.1G.lH.lH.2H.3H.4PlanFormulationandSelectionMethodologySelectedAlternativeHydroelectricSitesAlternativeHydroSitesTypicalDamSectionAlternativeHydroSitesSnowAlternativeHydroSitesKeetnaAlternativeHydroSitesCacheAlternativeHydroSitesBrowneAlternativeHydroSitesTalkeetna2AlternativeHydroSitesHicksAlternativeHydroSitesChakachamnaAlternativeHydroSitesChakachamna-ProfileandSectionsGenerationScenarioIncorporatingThermalandAlternativeHydropowerDevelopments-MediumLoadForecastDamsiteCostvsReservoirStorageCurvesDamsiteCostvsReservoirStorageCurvesDamsiteCostvsReservoirStorageCurvesMutuallyExclusiveDevelopmentAlternatives1995Month/AnnualPeakLoadRatiosEnergyForecastsUsedForGenerationPlanningStudiesDevilCanyonArchGravityDamSchemePlanandSections-GeneralArrangementDevilCanyonArchGravityDamSchemeSectionsWatanaArchDamGeometry-GeneralArrangementWatanaArchDamGeometry-SectionsAlongPlanesofCentersviii APPENDIXA -GENERICPLANFORMULATIONANDSELECTIONMETHODOLOGYOnnumerousoccasionsduringthefeasibilitystudiesfortheSusitnaHydro-electricProject,decisionsmustbemadeinwhichasingleorasmallnumberofcoursesofactionareselectedfromalargernumberofpossiblealternatives.Thisappendixpresentsageneralizedframeworkforthisdecision-makingprocessthathasbeendevelopedfortheSusitnaplanningstudies.Itoutlines,ingen-eralterms,theapproachusedinscreeningalargemultitudeofoptionsandfinallyestablishingthebestoptionorplan.Itiscomprehensiveinthatitakesintoaccountnotjusteconomicaspectsbutalsoabroadrangeofenvironmentalandsocialfactors.TheapplicationofthisgeneralizedmethodologyisparticularlyrelevanttothefollowingdecisionstobemadeduringtheSusitnastudies:-Selectionofalternativeplansinvolvingthermaland/ornon-Susitnahydro-electricdevelopmentsintheprimaryassessmentoftheeconomicfeasibilityofthe SusitnaBasindevelopmentplan(Task6).-SelectionofthepreferredSusitnaBasinhydroelectricdevelopmentplan(i.e.identificationofbestcombinationofdamsitestobedeveloped)(Task6).-SelectionofthepreferredRailbeltgenerationexpansionplan(i.e.comparisonofRailbeltplanswithandwithoutSusitna).-OptimizationoftheselectedSusitnaBasindevelopmentplan(i.e.determiningthebestdamheights,installedcapacities,andstagingsequences)(Task6).-Selectionofthepreferredtransmissionlineroutes(Task8).-Selectionofthepreferredmodeofaccessandaccessroutes(Task2).-Selectionofthepreferredlocationandsizeofconstructionandoperationalcampfacilities(Task2).Itisrecognizedthattheaboveplanningactivitiesembraceaverydiversesetdecision-makingprocesses.Thegeneralizedmethodologyoutlinedherehasbeencarefullydevelopedtobeflexibleandreadilyadaptabletoarangeofob-jectivesanddataavailabilityassociatedwitheachdecision.Thefollowingsectionsbrieflyoutlinetheoveralldecision-makingprocessanddiscusstheguidelinestobeusedforestablishingscreeningandevaluationcriteria.A-l A.l-PlanFormulationandSelectionMethodologyThemethodologytobeusedinthedecisionprocesscangenerallybesubdividedintofivebasicsteps(FigureA.l):-Step1:Determinebasicobjectivesoftheplannedcourseofaction-Step2:Identifyallfeasiblecandidatecoursesofaction-Step3:Establishabasistobeusedandperformscreeningofcandidates-Step4:Formulateplansincorporatingpreferredalternatives-Step5:Re-establishabasistobeused,evaluateplansandselectpreferredplanUnderStep2,thecandidatecoursesofactionareidentifiedsuchthattheysat-isfy,eitherindividuallyorincombinations,thestatedobjectives(TableAI).InStep3,thebasisofscreeningthesecandidatesisestablishedinitemsofredefined,specificobjectives,assumptions,database,criteriaandmethodol-ogy.Thisprocessfollowsasub-seriesofsevenstepsasshowninTableA.2toproduceashortlist,ideallyofnomorethanfiveorsixpreferredalterna-tives.PlansarethenformulatedinStep4toincorporatesinglealternativesorappropriatecombinationsofalternatives.TheseplansarethenevaluatedinStep5,usingafurtherredefinedsetofobjectives,criteriaandmethodology,toarriveataselectedplan.ThissixstepprocedureisillustratedinTableA.3.TablesA.2andA.3alsoindicatethereviewprocessthatmustaccompanytheplanningprocess.Itisimportantthat,withintheplanformulationandselectionmethodology,theobjectivesofeachphaseofthedecisionprocessberedefinedasnecessary.Attheoutsettheobjectiveswillbebroadandsomewhatgeneralinnature.Astheprocesscontinues,therewillbeatleasttworedefinitionsofobjectives.ThefirstwilltakeplaceduringStep3andthesecondduringStep5.Asanexample,thebasicobjectivesatStep1mightbethedevelopmentandapplicatiorofanappropriateprocedureforselectionofasingle,preferredcourseofaction.Step2mightinvolvetheselectionofthosecandidateswhicharetechnicallyfeasibleonthebasisofadefineddatabaseandsetofassumptions.TheobjectivesatStep3mightbetheestablishmentandapplicationofadefinecsetofcriteriaforeliminationofthosecandidateswhicharelessacceptablefromaneconomicalandenvironmentalstandpoint.Thiswouldbeaccomplishedonthebasisofanappropriatelymodifieddatabaseandassumptions.Havingdevelopedaseriesofplansincorporatingtheremainingorpreferredalterna-tivesunderStep4,theobjectivesunderStep5mightbetheselectionofthesinglealternativewhichbestsatisfiesanappropriatelyredefinedsetofcriteriaforeconomic,environmentalandsocialacceptability.A.2-GuidelinesforEstablishingScreeningandEvaluationCriteriaThedefinitionofcriteriaforthescreeningandevaluationprocedureswilllargelydependontheprecisenatureofthealternativesunderconsideration.However,inmostcasescomparisonswillbebasedontechnical,economic,environmentalandsocioeconomicfactorswhichwillusuallyinvolvesomedegreeoftrade-offinmakingapreferredselection.Itisusuallynotpossibletoadequatelyquantifysuchtrade-offs.A-2 tionalcriteriamayalsobeseparatelyconsideredinsomecases,suchasorconservationofnaturalresources.Guidelinesforconsiderationofmorecommonoverallfactorsare discussedinthefollowingparagraphs.TechnicalFeasibilityBasically,alloptionsconsideredmustbetechnicallyfeasible,completewithinthemselves,andmustensurepublicsafety.Theymustbeadequatelydesignedtocopewithallpossibleconditionsincludingfloodflows,seis-micevents,andallothertypesofnormalloadingconditions.EconomicCriteriaIncaseswhereaspecificeconomicobjectivecanbemetbyvariousalterna-tiveplans,thecriteriatobeusedistheleastpresentworthcost.Forexample,thiswouldapplytotheevaluationofthevariousRailbeltpowergenerationscenarios,optimizingSusitnaBasinhydroelectricdevelopments,andselectionofthebesttransmissionandaccessroutes.Incaseswherescreeningofalargenumberofoptionsistobecarriedout,unitcommoditycostscanbeusedasabasisofcomparison.Forinstance,energycostin$/kwhwouldapplytoscreeninganumberofhydroelectricdevelopmentsitesdistributedthroughoutsouthernAlaska.Similarilythescreeningofalternativeaccessortransmissionlineroutesegmentswouldbebasedona$/milecomparison.BecausetheSusitnaBasindevelopmentisastateproject,economicparametersaretobeusedforallanalyses.Thisimpliestheuseofreal(inflationadjusted)interestratesandonlythedifferentialescalationratesaboveorbelowtherateofgeneralpriceinflation.Intra-statetransferpaymentssuchastaxesandsubsidiesareexcluded,andopportunityvalues(orshadowprices)areusedtoestablishparameterssuchasfuelandtransportationcosts.Extensiveuseshouldalsobemadeofsensitivityanalysestoensurethattheconclusionsbasedoneconomicsarevalid forarangeofthevaluesofparametersused.Forexample,someofthemorecommonparametersconsid-eredincomparisonsofalternativegenerationplansparticularlylendthemselvestosensitivityanalyses.Thesemayinclude:-Loadforecasts-Fuelcosts-Fuelcostescalationrates-Interestanddiscountrates-Economiclifeofsystemcomponents-CapitalcostofsystemcomponentsA-3 (c)EnvironmentalCriteriaEnvironmentalcriteriatobeconsideredincomparisonsofalternativesarebasedontheFERC(1)requirementsforthepreparationoftheExhibitE"EnvironmentalReport"tobesubmittedaspartofthelicenseapplicationfortheproject.Thesecriteriaincludeprojectimpactson:-Physicalresources,air,waterandland-Biologicalresources,flora,faunaandtheirassociatedhabitats-Historicalandculturalresources-LanduseandaestheticvaluesInadditiontotheabovecriteria,whichareusedforcomparingorrankingalternatives,thefollowingeconomicaspectsshouldalsobeincorporatedinthebasicalternativesbeingstudied:-Indevelopingthealternativeconceptsorplans,measuresshouldbein-corporatedtominimizeorprecludethepossibilityofundesirableandirreversiblechangestothenaturalenvironment.-Effortsshouldalsobemadetoincorporatemeasureswhichenhancethequalityaspectsofwater,landandair.Careshouldbetakenwhenincorporatingtheaboveaspectsinthealterna-tivesbeingscreenedorevaluatedtoensureconsistencybetweenalterna-tives,i.e.thatallalternativesincorporatethesamedegreeofmitiga-tion.Asanexample,thesemeasurescouldincludereservoiroperationalconstraintstominimizeenvironmentalimpact,incorporationofairqualitycontrolmeasuresforthermalgeneratingstations,andadoptionofaccessroadandtransmissionlinedesignstandardsandconstructiontechniqueswhichminimizeimpactonterrestrialandaquatichabitat.(d)SocioeconomicCriteriaBasedgenerallyonFERCrequirements,theprojectimpactassessmentshouldbeconsideredintermsofsocioeconomiccriteriawhichinclude:-ImpactonlocalcommunitiesandtheavailabilityofpUblicfacilitiesandservices-Impactofemploymentontaxandpropertyvalues-Displacementofpeople,businessesandfarms-DisruptionofdesirablecommunityandregionalgrowthA-4 A.3-PlanSelectionProcedureAsnotedabove,foreachsuccessivescreeningexercise,thecriteriacanberefinedormodifiedinordertoreduceorincreasethenumberofalternativesbeingconsidered.Asageneralrule,noattemptwillbemadetoascribenumeri-calvaluestonon-quantifiableattributessuchasenvironmentalandsocialimpactsinordertoarriveatanoverallnumericalevaluation.Suchaprocesstendstomaskthejudgementaltradeoffsthataremadeinarrivingatthebestplan.Theadoptedapproachinvolvesutilizingcombinationsofbothquantifiableandqualitativeparametersinthescreeningexercisewithoutmakingtradeoffs.Forexample,thescreeningcriteriausedmightbe:-II•••alternativeswillbeexcludedfromfurtherconsiderationiftheirunitcostsexceedXand/oriftheyarejudgedtohaveasevereimpactonwildlifehabitat...IIThisapproachispreferabletocriteriawhichmightstate:-II•••alternativeswillbeexcludedifthesumoftheirunitcostindexplustheenvironmentalimpactindexexceedsY...11Nevertheless,itisrecognizedthatundercertaincircumstances,particularlywherearelativelylargenumberofverydiversealternativesmustbescreenedveryquickly,thelatterquantitativeapproachmayhavetobeused.Inthefinalplanevaluationstages,carewillbetakentoensurethatalltradeoffsthathavetobemadebetweenthedifferentquantitativeandqualita-tiveparametersused,areclearlyhighlighted.Thiswillfacilitatearapidfocusonthekeyaspectsinthedecision-makingprocess.Anexampleofsuchanevaluationresultmightbe:-II•••PlanAissuperiortoPlanB.Itis$XmoreeconomicandthisbenefitisjudgedtooutweighthelowerenvironmentalimpactassociatedwithPlanB...11SufficientdetailedinformationshouldbepresentedtoallowareviewertomakeanindependentassessmentofthejUdgementaltradeoffsmade.Theapplicationofthisprocedureintheevaluationstageisfacilitatedbyperformingtheevaluationsforpairedalternativesonly.Forexample,iftheshortlistplansareA,B,andC,thenintheevaluationPlanAisfirstevalu-atedagainstPlanB,thenthebetterofthesetwoisevaluatedagainstCtoselectthebestoverallplan.A-5 LISTOFREFERENCES(1)CodeofFederalRegulations-Title18;Parts2,4,5,16and131.A-6 TABLEA.1-STEP2 -SELECTCANDIDATESStep2.1-Identificationofcandidates:-objectives-assumptions-database-selectioncriteria-selectionmethodologyStep2.2-ListanddescribecandidatesthatwillbeusedinStep3.TABLEA.2-STEP3 -SCREENINGPROCESSStep3.1-Establish:-objectives-assumptions-database-screeningcriteria-screeningmethodologyStep3.2-Screencandidates,usingmethodologyestablishedinStep3.1toconductscreeningofalternatives.Step3.3-Identifyanyremainingindividualalternatives(orcombinationsofalternatives)thatsatisfytheobjectivesandmeetthecriteriaestablishedinStep3.1undertheassumptionsmade.Step3.4-Determinewhetherasufficientnumberofalternativesremaintoformulatealimitednumberofplans.Ifnot,additionalscreeningviaSteps3.1through3.3isrequired.Step3.5-Prepareinterimreport.Step3.6Reviewscreeningprocessvia(asappropriate):-Acres-APA-ExternalgroupsStep3.7-Reviseinterimreport. TABLEA.3-STEP5 -PLANEVALUATIONANDSELECTIONStep5.1-Establish:-objectives-evaluationcriteria-evaluationmethodologyStep5.2-Establishdatarequirementsanddevelopdatabase.Step5.3-Proceedwiththeplanevaluationandselectionprocessasfollows:-Identifyplanmodificationstoimprovealternativeplans-Basedontheestablisheddatabaseandtheselectioncriteria,useapairedcomparisontechniquetoranktheplansas(1)thepreferr-edplan,(2)thesecondbestplan,and(3)otherplans;-Identifytradeoffsandassumptionsmadeinrankingtheplans.Step5.4-Preparedraftplanselectionreport.Step5.5-Reviewplanselectionprocessvia(asappropriate):-Acres-APA-ExternalgroupsStep5.6-Preparefinalplanselectionreport. TABLE A.4 -EXAMPLES OF PLAN FORMULATION AND SELECTION METHODOLOGY i~~-DeTrne-------T ..:>elect--.~4;.Plan Activity Objectives Alternatives 3.Screen Formulation 5.Evaluation Susitna Basin Development Selection Access Route Selection Select best Susitna Basin hydropower development plan Select best access route to the pro- posed hydro- power develop- ment sites within the basin for purposes of construction and operation All alternative dam sites in the basin,e.g.: Devil Canyon; High Devil Canyon; Watana Susitna III; Vee; Maclaren; Butte Creek; Tyone; Denali ; Gold Creek; Olson; Devil Creek; Tunnel Alternative All alternative road,rail,and air transport component links, e.g.: road and rail links from Gold Creek to sites via north and south routes; Road links to sites from Denali Highway; Screen out sites which are too small or are known to have severe environ- ment al impacts Screen out links which are either more costly or have higher environmental impact than equivalent alternatives. Ensure suffi- cient links remain to allow formulation of plans Se lect several combinations of dams which have the potential for delivering the lowest cost ene rgy in the basin,e.g.: Watana-Devil Canyon dams; High Devil Canyon-Vee dams; Watana Dam - Tunnel Select several different access plans,e.g.: Gold Creek road access; Gold Creek road/ rail access; Dena li Highway road access Conduct detailed evaluation of development plans Conduct detailed evaluation of development plans Air links to sites and associated landing facilities INPUT FROM AVAILABLE SOURCES -PREVIOUS AND CURRENT STUDIES DEFINE OBJECTIVES SELECT CANDIDATES FEEDBACK FEEDBACK LEGEND ---'\STEP NUMBER IN 4 STANDARD PROCESS (APPENDIX A ) PLAN FORMULATION AND SELECTION METHODOLOGY FIGURE A.I iiJ APPENDIXB -THERMALGENERATINGRESOURCESThepurposeofthisAppendixistodefinethethermalgeneratingresourcesavailabletotheRai1be1tduringthe1980-2010studyperiod.Toaddressthermalresources,itisnecessarytoreviewtheexistingthermalcapacity,fuelavail-abilityandassociatedcostsaswellasreviewfutureplantcapacitiesandcapi-talcostsfordevelopment.Todeveloptheparametersnecessaryforgeneration.planningstudies,itisalsonecessarytoassessoperationandmaintenancecosts,andplannedandforcedoutages.ThecontentsofthissectiondocumentthedatausedinthegenerationplanningstudiesdescribedinSections6and8.B.1-FuelAvailabilityandCostsFuelsourcesavailableintheRai1be1tregionforfutureelectricgenerationplantsareprimarilycoalandnaturalgas.Distillate,althoughnotexpectedtoplayamajorrole,isdiscussedbriefly.ItisunlikelythatoilwillbeusedastheprimaryfuelforadditionstothegenerationsystemintheRai1be1tduetopublicpolicyandhighvalueforotheruses.TablesB.1,B.2andB.3summar-izeestimatedfuelreserves.TableB.4listscurrent(1980)fuelpricesintheRai1be1tregion.TableB.5summarizesthedevelopedfuelcostswhichrepresentopportunity(shadow)values,assumingactiveinternationalmarketingofAlaskanfuels,asdiscussedinthefollowingsections.(a)CoalAlaskancoalreservesincludethefollowingcoalproducingfields(2):-Nenana-Matanuska-Beluga-Kenai-BeringRiver-HerendeenBay-ChignikBayOftheseeightregions,onlyfourhavepotentialforRai1be1tuse.TableB.1listspertinentinformationofthesefourcoalreserves.TheBelugafield,whichispartofthelargerSusitnaCoalDistrict,isanundevelopedsourcelocated45to60mileswestofAnchorageonthewestbankofCookInlet.Coalminingatthislocationwouldrequiretheestab-lishmentofaminingoperation,transportationsystemandsupportingcom-munityandinfrastructure.AnumberofstudieshavebeenconductedonthereserveslocatedintheBelugaCoalFields.Ithasbeenestimatedthatthreeareas(theCapps,ChuitnaandThreeMilefields)contain2.4billiontonsofcoalandthatinexcessof400milliontonscanbestrippedwithoutexceedingeconomiclimitsoncoal/overburdenratios.TheexistingNenanacoalfield,whichislocatedinthevicinityofFair-banks,isprimarilyleasedbyUsibelliCoalMineIncorporated.Thefieldrangesfromlessthanamiletomorethan30milesinwidthforabout80milesalongthenorthflankoftheAlaskaRange.Nenanacoalisprimarilyminedbysurfacemethods.Anestimated95milliontonsofcoalisavail-ablebystripping,andanestimatedtotalinexcessof2billionadditionaltonsofcoalcouldbeextractedbyundergroundmining.B-1 TheMatanuskacoalfields,eastofAnchorage,occupymostoftheMatanuskaValley.Althoughstrippingandundergroundminingofthissourcehavebeenundertaken,strippingislimitedduetorelativelysteepdipsandincreas-inglythickoverburden.Reservesareestimatedat50milliontons,andul-timateresourcevaluemaybe100milliontons.Althoughlimitedusageispossiblelocally,potentialasasignificantRailbeltsourceisunlikely(3).ThefourthpotentialcoalproducingregionistheKenaicoalfieldintheKenailowlands,southofTustumenaLakeontheeasternshoreofCookInlet.Resourcesareestimatedat300milliontons.Thesecoalseamsarethinandseparatedvertically,makingminingextremelydifficult.LimiteduseofcoalintheRailbeltatpresentisaresultofanundevelop-edexportmarketandtherelativelysmalllocaldemandforthisfuel.Cur-rentlytheUsibelliCoalCompanyminesNenanacoalatafacilitylocatedinHealyandproducesapproximately0.7milliontons/year.Thiscoalrepre-sentstheonlymajorcommercialcoaloperationinAlaska.Thecoalistruckedseveralmilesfromtheminesitetoa25MWpowerplantownedandoperatedbytheGoldenValleyElectricAssociation(GVEA)atHealy.Thedeliveredcostisapproximately$1.25permillionBtu(MMBtu).TheNenanacoalisalsotrucked8-1/2milestoarailwayspurloadingstationatSusitanafortransporttoFairbanks,adistanceof111miles.ThiscoalisdeliveredtotheChenaStation(capacity29MW),ownedbyFairbanksMunici-palUtilitySystem(FMUS),atanextracostofapproximately$O.34/MMBtubringingthepricetoFMUSto$1.40/MMBtu.CoalminedatHealyisalsousedforgenerationinunitsatFortWainwrightArmybaseandtheUniver-sityofAlaskapowerplants.VariousproposalshavebeenmadeforexpandedproductionintheNenanacoalfieldwhichwouldnearlydoubletheproduction.InSeptember,1980,acontractbetweenJapanandtheownersoftheHealyoperationwassignedtotransportcoaltoSewardviatheAlaskanRailroadforbargingtoJapan.Detailsandcostsofthisproposalarenotavailableatthistime.Otherexpansionoptionsinclude:-EnlargetheHealygenerationplantto100MW(75MWaddition).ThiswasproposedjointlybyGVEAandFMUS.However,thelocationoftheHealyplant4.5milesfromMt.McKinleyNationalParkmayrestrictdevelopmentduetoincreasedcostsassociatedwithmeetingairqualitystandards.-ExpandtheFMUSChenagenerationplantorbuildanewjointFMUS/GVEAplantatFairbankstosupplydistrictheatandincreasedelectricpowercapability.TransportHealyminedcoalapproximately55milesnorthviatheAlaskaRailroadtoNenanaandbuilda100MWexpansionthere.However,accord-ingtoGVEAandFMUS,thisexpansionplanhasbeenpostponeddueinparttoslowingdemandgrowthandenvironmentalrestrictions.-TransportHealyminedcoalapproximately200milessouthviatheAlaskaRailroadtoAnchorageforutilizationinnew200or400MWcoal-firedplants.Thisoptionisthoughtpossible,buttheeconomicsofcoaltransportatthenecessarycapacityviatheexistingrailsystemisinquestion.DevelopmentatBelugamayalsoprecludethisoption.B-2 TwopotentialdevelopershaveauthorizedstudiesoftheBelugacoaldis-tricttodeterminetheeconomicsandfeasibilityofextensivedevelopment.Placer-AmexIncorporatedhasextensiveholdingsthroughouttheBelugadis-trictandBass-Hunt-WilsonVenturehasholdingsintheChuitnafield.(i)Placer-AmexHoldingsAnextensivestudyofthepotentialofthePlacer-Amexholdingswascompletedin1980bytheAlaskaDivisionofEnergyandPowerDevelop-ment(16).ThisreportsummarizesthepotentialofdevelopmentoftheCookInletRegioncoalfield.Severaloptionswereshowntoexistfordevelopment.ThefirstoptionwquldbedevelopmentbyBelugaCoalCompany(awhollyownedsubsidiaryofPlacer~AmexInc.)withinthenexttwoorthreeyears.However,sincemostoftheproposedprojectoutputisexported,theycannotbegininitiationuntilafirmmarketiscontractedforthecoal.Thesecondoptionistheconstructionofacoal-firedgeneratingplantbytheChugachElectricAssociation(CEA).Thisoptionisdependentupongovernmentmandatedrequestsforutilitiestoconvertfromnaturalgastocoal.TheCEAhascurrentlynofirmplanstoconstructsuchaplant.Basedonthesetwooptions,fourpossiblelevelsofdevelopmentatBelugaareconsideredandwereevaluatedinthe1980reportnotedabove.-Lowlevelofcoalminingtosupplylocalgeneratingfacilities.DevelopmentcouldoccuriftheCEAisrequiredbygovenmentmandatet~replacenaturalgasunitswithcoalunits.ThisscenariowouldrequiremoderatedevelopmentofaworkcampatBeluga,andwouldincludetwo200MWgeneratorsusingapproximately1.5milliontonsperyear.Constructionwouldbeduringtheperiod1980-1986.- Asufficientlylarge(atleastsixmilliontonsperyear(MMTPY))exportmarketisdevelopedandnogeneratingstationsareconstruc-ted.Thisfigureisconsideredtheminimumamountnecessaryforcosteffectiveexporting.Inthiscase,apermanentworkcampwouldbeestablishedsimilartothefirstscenario.Exportingwouldbeginin1990.-Two200MWcoal-firedgeneratingplantsandasixMMTPYcoalexport-ingfacilitycouldjustifythenecessaryfront-endcapitalinvest-menttoestablishapermanentcommunityatBeluga.Thiswouldalsoentailsecondaryeconomicdevelopment.-ThereisadistinctpossibilitythatnodevelopmentoftheBelugacoalfieldwilloccurbefore1990.Exportscenariosalsoincludebarging3500milestoJapanor2100milestoSanFranciscoandaslurrypipelineschemetothePacificNorthwest(28).SupplyingAnchoragewithcoalviaanewrailroadtiedoesnotappeartobeanoptionconsideredforthenearfuturedevel-opment(28).B-3 (ii)Bass-Hunt-WilsonHoldingsThestudyoftheBelugaCoalFieldpotentialattheBass-Hunt-Wilson(BHW)coalleasesintheChuitnaRiverFieldwascompletedbyBechtelCorporationinApril1980(27).Thisstudyresultedina7.7MMTPYeconomicexportproductionratewithnoconsiderationoflocalcoal-firedgeneratingdevelopments.PotentialexportmarketsforBelugacoalasdefinedintheprevioussectionincludetheentireLower48statesorCalifornia,PacificNorthwestandJapanmarkets.TheaveragemarketpriceforcoalinCaliforniaandthePacificNorthwestregion,asreportedinJune,1980totheU.S.DepartmentofEnergy,rangedfrom$1.55/MMBtuto$1.46/MMBtu.Thesepricesareslightlyhigherthantheaverageu.s.price.ThecostsoftransportingBelugaminedcoaltothePacificNorthwestortoCaliforniawereestimatedina1977Reporton"AlaskaCoalandthePacific."(2)ThesepriceswereestimatedandappearinTableB.5.TheBelugacoalstudiesdoneforPlacer-AmexandtheBass-Hunt-Wilsonven-turehaveresultedinopportunitycostsforcoalof$1.00-$1.33/MMBtu.Forpurposesofthisstudythevalueof$1.15/MMBtuwillbeusedforsuppliestofuturecoal-firedgeneratingplantsconstructedinAlaska(TableB.5).AreportissuedinDecember,1980byBattellePacificNorthwestLaboratory(50)analyzedmarketopportunitiesforBelugacoal.ResultsreportedinthisreportweregenerallyconsistentwithearlierBattelleandDOEstudies.(b)NaturalGasNaturalgasresourcesavailableorpotentiallyavailabletotheRailbeltregionincludetheNorthSlope(PrudhoeBay)reservesandtheCookInletreserves.InformationonthesereservesissummarizedinTableB.2.ThePrudhoeBayFieldcontainsthelargestaccumulationofoilandgaseverdiscoveredontheNorthAmericancontinent.Thein-placegasvolumesinthefieldareestimatedtobeinexcessof40trillioncubicfeet(Tcf).Withlossesconsidered,recoverablegasreservesareestimatedat29Tcf.GascanbemadeavailableforsalefromthePrudhoeBayFieldatarateofatleast2.0billioncubicfeetperday(Bcfd)andpossiblyslightlymorethan2.5Bcfd.Atthisrate,gasdeliveriescanbesustainedfor25to35years,dependingonthesalesrateandultimategasrecoveryefficiency.Duringthemid-seventies,threenaturalgastransportsystemswereproposedtomarketnaturalgasfromtheNorthSlopeFieldstotheLower48states.Twooverlandpipelineroutes(AlcanandArctic)andapipeline/LNGtanker(ElPaso)routewereconsidered.TheAlcanandArcticpipelineroutestraversedAlaskaandCanadaforsome4000to5000miles,terminatinginthecentralU.S.fordistributiontopointseastand/orwest.TheElPasoproposalinvolvedanoverlandpipelineroutethatwouldgenerallyfollowtheAlyeskaoilpipelineutilitycorridorforapproximately800miles.Aliquefactionplantwouldprocessapproximately37millioncubicmetersofB..A gasperday.ThetransferstationwasproposedatPointGraviniasouthoftheValdezterminationpoint.Eleven165,000cubicmetercryogenictankerswouldtransporttheLNGtoPointConceptioninCaliforniaforregasification.Thestudiesnotedabovehaveconcludedwiththeinitiationofa4800mile,2.4Bcfd,Alaska-Canadanaturalgaspipelineproject,costingbetween$22and$40billion,expectedtobeoperationalby1984-1985.Thepipelineprojectpassesapproximately60milesnortheastofFairbanks.TheCookInletReserves(TableB.2)arerelativelysmallincomparisontotheNorthSlopereserves.Gasreservesareestimatedat4.2Tcfascom-paredto29TcfinPrudhoeBay.Ofthe4.2Tcf,approximately3.5Tcfisavailableforuse;theremainingreservesareconsideredshut-inatthistime.ThegasproductioncapabilityintheKenaiPeninsulaandCookInletregionfarexceedsdemand,asnomajortransportationsystemexiststoex-portmarkets.Asaresultofthissituation,thetwoAnchorageelectricutilitieshaveasupplyofnaturalgasataveryeconomicprice.ExportfacilitiesforCookInletnaturalgasincludeoneoperatingandonepro-posedLNGscheme.Thefacilityinoperation,theNikiskiterminal,ownedandoperatedbyPhillips-Marathon,islocatedontheeasternshoreofCookInlet.TwoLiberiancryogenictankerstransportLNGsome4000milestoJapan.Thevolumeproducedis185MMCFDwithrawnaturalgasrequirementsof70percentfromaplatforminCookInletand30percentfromexistingonshorefields.In1979,thePacificAlaskaLNGCompany(PALNG)proposedtoshipLNGtoCaliforniafromaterminaltobeconstructedatNikiskiontheKenaiPenin-sula.Thisplantwouldultimatelyprocessupto430MMCFDforshipmentviatwocryogenictankerstoLittleCojo(nearPointConception),California.TheFederalEnergyRegulatoryCommission(FERC)hasplacedariderontheprojectpermit,stipulatingthatin-placeandcommittedgasreservesmusttotal1.6Tcfbeforealicenseisgranted.10datePALNGestimates1.0Tcfisinplace.ThereisalsosomepotentialforagaslinespurtobeconstructedfromtheCookInletregionsome310milesnorthtointersectwiththeAlaska-CanadanaturalgaspipelineprojectinordertomarkettheCookInletgas.Thisconcepthasnotbeenextensivelystudiedbutcouldprovetobeaviablealternative.MarketsforPrudhoeBaygaswerenotconsideredindevelopingamarketpriceforRailbeltfuelalternativessinceanexistingmarketandtranspor-tationsystemhasbeendevelopedwiththeinceptionoftheAlaska-Canadapipelineproject.MarketsforCookInletgasincludetheLower48statesviatwotransporta-tionmodes:LNGtankersorapipelinespurconstructedfromAnchoragetoDeltaJunctionandintersectingwiththeAlaska-Canadapipeline.TheregulatedceilingmarketpricefornaturalgasonthewestcoastasreportedintheFederalRegister,DepartmentofEnergy,Tuesday,October27,1980was$4.89/MMBtuintheRegion10area(Washington,Oregon,California).TheaveragereportedU.S.pricewas$3.58/MMBtu.ShipmentofgastothesemarketsviatheLNGtankerschemeasproposedbyPALNGwas8-5 wasestimatedtocost$2.50/MMBtufortransportationandprocessing.Alternatively,thecostforshipmentviaa310-milepipelinespurfromCookInlettotheAl-Canpipelinewasestimated(basedoncostdataavailablefromthecurrentpipelineproject)tobe$1.97/MMBtu.ThisincludestheincrementalcostoftheAlaska-Canadapipeline($1.27/MMBtu)andthecostofthetapfromCookInlet($O.70/MMBtu).TableB.5liststheresultingAlaskanopportunityvaluesunderthesetwoassumptionsformarketsinRegion10andtheLower48states.ThecurrentJapanesemarketpricefornaturalgassalesfromtheNikiskiLNGprojectis$4.50to$4.65/MMBtu(46).BasedoninformationcollectedfromNikiski,transportationandprocessingcostswereestimatedtobe$3.00/MMBtu.ThisresultsinanAlaskanopportunityvalueof$1.50to$1.65/MMBtu.Theresultingpricesdevelopedintheseanalysesrangefrom$1.08to$2.92/MMBtu.Forpurposesofthisstudy$2.00/MMBtuwasadoptedastheopportunityvalueofnaturalgasinAlaska.(c)OilBoththeNorthSlopeandtheCookInletFieldshavesignificantquantitiesofoilresourcesasseeninTableB.3.NorthSlopereservesareestimatedat8375millionbarrels.OilreservesintheCookInletregionareesti-matedat198millionbarrels(14).Asof1979,thebulkofAlaskacrudeoilproduction(92.1percent)camefromPrudhoeBay,withtheremainderfromCookInlet.Netproductionin1979was1.4millionbarrelsperday(11).OilresourcesfromthePrudhoeBayfieldaretransportedviathe800miletrans-Alaskapipelineatarateof1.2millionbarrelsperday.Inexcessof600shipsperyeardeliveroilfromtheportofValdeztothewest,GulfandeastcoastsoftheU.S.Approximately2percent(or10millionbar-rels)ofthePrudhoeBaycrudeoilwasusedinAlaskarefineriesandalongthepipelineroutetopowerpumpstations(14).TheNorthPoleRefinery,located14milessoutheastofFairbanks,issupplied~thetr~ns-Alaskapipelineviaaspur.Refiningcapacityisaround25,000barrelsperdaywithhomeheatingoils,dieselandjetfuelstheprimaryproducts.MuchoftheinstalledgeneratingcapacityownedbyFairbanks·utilitiesisfueledbyoil.FMUShas38.2MWandGVEAhas186MWofoil-firedcapacity.Duetothehighcostofoil,theseutilitiesuseavailablecoal-firedcapacityasmuchaspossiblewithoilusedasstandbyandforpeakingpurposes.CrudeoilfromoffshoreandonshoreKenaioilfieldsisrefinedatKenai,primarilyforusein-state.ThermalgeneratingstationsinAnchoragerelyonoilasstandbyfuelonly.SincetheinstallationoftheAlyeskaoilpipeline,whichhasmadeAlaskanoilmarketable,theopportunitycostofoiltoAlaskahasbeentheexistingmarketprice.Contractsforoiltoutilitieshaverangedfrom$3.45/MMBtuto$4.01jMMBtuasreportedtoFERC.ForpurposesofthegenerationB-6 expansionstudy,whereoilisconsideredonlyavailableforstandbyunits,thepriceadoptedforuseis$4.00/MMBtu(TableB.5).B.2-ThermalGeneratingOptions-CharacteristicsandCostsTheanalysisofthermalgeneratingresourcesavailabletomeetfutureRailbeltneedsrequiresthedetaileddeterminationofexistinggeneratingcapacity,itsuse,conditionandplannedretirementpolicyinadditiontocommittedthermalplantexpansions.Ofthe943.6MWofexisting(1980)capacityintheRailbeltregion,95percentofcapacityreliesonfossilfuels(TableB.6).AsummaryofcapacitybyunittypeisgiveninTableB.7.ByfarthemostimportantthermalgeneratingresourcesavailabletotheRailbeltin1980,arethenaturalgas-firedgasturbinesintheAnchorage/CookInletre-gion(TableB.7).TherecenttrendofbothAnchorageMunicipalLightandPowerDepartment(AMLPD)andtheCEAhasbeentomeetfuturegeneratingneedsusingcombinedcycleadditionstoexistinggasturbineunits.ThisongoingtrendisillustratedbytheanticipatedexpansionofCEA'ssystemwiththeBelugaNo.8unit(60MW)andthemostrecentAMLPDexpansionofunitNo.6attheirGeorgeM.SullivanPlant.TheseunitsallrelyonlocallycontractedCookInletnaturalgasforgeneration.Oil-firedgenerationbygasturbinesisgenerallyconfinedtotheFairbanksre-gionwithunitsownedandoperatedbyGVEAandFMUS.Inaddition,thesetwoutilitiesownandoperatethe54MWofcoal-firedsteamcapacityusingHealycoal.SmalldieselunitsareusedforpeakingandstandbyserviceintheFair-banksregion..Thecapitalcostsforfourdifferenttypesofthermalgeneratingplantsconsid-eredavailabletotheRailbeltregionwereestimated.Capitalcostestimatesforcoal-firedsteam,combinedcycle,gasturbinesanddieselsappearinTablesB.8toB.13.TableB.13summarizesthegenerationparametersnecessaryfortheproductioncostmodelinthegenerationplanningstudiesdescribedinSection8.Capitalcostsfornewfossil(coal)thermalplantalternativesareaninputtoanygenerationplanningstudy.Thedevelopmentofcapitalcostestimatesofhighaccuracygenerallyconsumessubstantialtimeandeffortforasingleplantdesignataspecifiedlocation.Thedevelopmentofdetailedcostestimatesfornumerousplanttypesatnon-specificlocationstobeselectedatsomefuturetimewouldbeaformidabletask.Theapproachtakeninthisstudyhasbeentodevelopgenericcoal-firedplantcostestimates,largelybaseduponpublishedLower48states'costdata,previousstudiesofAtaskanconstructioncostdif-ferentials,andrecentAlaskanconstructionexperiences.Gasturbinecombinedcycleanddieselplantsaretypicallymodularizedunits,withmajorcostvariationslargelytiedtospecifiedsiteconditionsorrestric-tions.Costsusedfortheseitemswerebasedonmanufacturersuppliedinforma-tionandpublishedbidinformationforunitstobeinstalledintheRailbeltre-gion.B-7 (a)Coal-FiredSteamAspreviouslymentionedtherearecurrentlyfourcoal-firedsteamplantsinoperation.The29MWChenaunitisoperatedbyFMUSandanother25MWplantisoperatedbyGVEAatHealy.Twomorecoalunits,withatotalcapacityof6MW,supplyFortWainwrightandtheUniversityofAlaskaatFairbankswithheatandelectricpower.ThesetwounitssupplyFMUSonacontractualbasis,whenavailable.AlloftheseplantsaresmallincomparisontonewelectricutilityunitstypicallyunderconsiderationintheLower48states.Up-to-datecostcomparisonsforpotentialnewinstallationsinAlaskawerethereforedifficult.Otherfactorsthathavebeenconsideredindevelopingcostsfornewinstal-lationsinclude:Large,newcoal-firedplantswillrequireextensiveemissioncontrolequipmenttomeetcurrentEPAemissionstandards-Largerplantsinvolvelongerconstructionperiods-Currenthighinterestandescalationrateshavedrivencostsofnewplantstomuchhigherlevelsthanpreviouslyexperienced(i)DeviationofPlantCostsBasedonprojectedAlaskanplantcapacityadditionsdevelopedinpreviousstudies,coal-firedunitsizesof100,250,and500MWwereconsideredforcapacityadditions.Itisunlikelythata500MWplantwouldbeproposedforlocalsupplytoeitherAnchorageorFairbanksduetolimitedpowerde-mandandfueltransportationcapacity.TheremotenessofFairbanksalsopossiblyprecludestheuseof500MWplants.However,installationofsuchaplantasabaseloadunit,perhapsintheBelugacoalfieldregion,tofeedanintegratedutilitygridisapossibility.SincetypicalplantunitsizesrequiredinAlaskaaresubstantiallysmallerthanthosetypicaloftheLower48states,previousstudieshavethereforeincorporatedrelation-shipsforeconomyofscale,baseduponLower48data(3,17).TheregionaldifferencesinAlaskanconstructioncostscanalsobesubstantial,withtheresultthatAlaskanlocationadjustmentfactorshavealsobeenusedintheserecentstudies(3).Costdifferencesmaybeduetotransportationrequirements,laborcosts,climate,anddistancefromequipmentsupplies.AreviewofAlaskanconstructioncostlocationadjustmentfactorswasundertakenbyBattelleinMarch1978(3).Theseadjustmentfactors,iden-tifiedfordifferentlocationsintheRailbelt,rangedfrom1.35to1.7forAnchorage,1.8to2.75forBeluga,and2.20to2.42fortheHealy/Nenana/Fairbanksarea.ThefactorsfinallyadoptedbyBattellefortheirstudywere1.65,1.80and2.20forAnchorage,BelugaandtheHealy-Fairbanksarea,respectively.TheBattellestudyincludedareviewofmaterialcostadditionsduetotransportationandlaborcostvariationsduetolackofdevelopedsocialinfrastructureinmanyareasinthestate.TheBattellestudyexaminedtheBelugacoalfieldsasapowerplantsite.ParticularattentionwaspaidtothevariationincostsassociatedwithB-8 developmentofalargelyuninhabitedarea.Landwasconsideredtobelowerincostthaninotherregions,andthesitefavoreduseofpreassembledplantmodulesbargedtothesite;bothitemsproducedcostreductions.Costincreasesresultedfromconstructionofworkertownsandtransportofequipment,food,fuelandothersupplies.IntheHealyarea,modularizedconstructionoflargeunitswouldnotbepossiblesincetransportationopportunitiesarelimitedtotheabilityofAlaskanrailroadstocarrylargeloads.Therefore,theneteffectontheadjustmentfactorisincreased.ThereisasignificantamountofuncertaintyregardingtheuseofAlaskanlocationadjustmentfactorsderivedinpreviousstudies•.Consequently,attemptsweremadetocrosscheckthevalidityoftheBattellefactorswithindependentdevelopmentofcostsforongoingAlaskanprojectsandevalua-tionoftheBattellesourceswheneverpossible.Capacityscalingfactors,asusedbyEPRIandBattelleinpreviousstudies,extrapolatecostsoflargerunits(500-1000MW)tosmallerunits(100-500MW).Underthisprocedure,thecostofasmallerunitcanbecomputedgiventhecostofalargerunitandanexponentialscalingfactor.Thisprocedure,exercisedwithcautionovernomorethanatenfoldrangeofcap-acity,canproducepreliminaryfiguresforcostcomparison.Battelle,intheirstudyofAlaskanelectricpower,usedcapacityscalingfactorsof0.85inthe200-1000MWrangeand0.60inthe100-200MWrange(3).Recog-nizingtheinaccuraciesassociatedwithusingcapacityscalingfactors,theuseoftheexponentapproachwaslimitedandwasreviewedforconsistencyonceapplied.Afurthercheckwasmadebymeansofcostsensitivityassessmentsingenerationplanningstudies(Section8).(ii)BasisofPlantCostEstimatesThecoal-firedplantcostestimatesdevelopedforinputintothermalgener-atingoptionswerebasedonanEPRIdocumentnumberAF-342,preparedbyBechtel(17).Thisreportextensivelydetailsthecostsof1000MWcoalplantsinvariousLower48locations.Thebaselineplant,usedtodevelopAlaskancosts,wasdesignedforaremotelocationinOregonwithmaximumenvironmentalcontrols.ThisplantusedWyomingcoalswhichhavesimilarcharacteristicstoAlaskancoals.Thecostestimateswerebasedonthefollowingdesignassumptions:-Theplantlocationassumesbothmake-upwaterandrailaccessavailable,butatsomedistancefromthesite.Ariverintakeandpumpingplantwouldsupplyrawriverwatertoasurgepondthroughathirteen-milelongpipeline.-CoalwouldberaildeliveredbyunittraininopengondolacarsforrotarydumpserviceoB-9 Theplantdesignhasassumedtoincludethefollowingsystems:-Coalhandlingsystem-Auxiliaryboilersystem-Rawwatersupplysystem-Fireprotectionsystem-Plantrainrun-offsystem-Lightoilsupplysystem-Heatingandventilatingsystem-Boilersystem-Turbinegeneratorsystem-Condensatesystem-Extractionsteamsystem-Mainsteamandreheatsystem-Circulatingwaterandcoolingtowersystem-Rainwatersystem-Chemicaltreatment-Ashhandling-Wastewaterdisposal-AirqualitycontrolTheairqualitycontrolsystemisdesignedtocontrolsulphurdioxideemis-sionsandparticulates.ThissystemwasconsideredparticularlyimportantduetotheairqualityoftheAlaskanenvironment.Theswitchyardcostincludes:-Circuitbreakers-Disconnectswitches-Linetraps-Potentialdevices-Lightningarresters-Foundations-Controlbuildings-Supportingstructures-Take-offtowers-Singlealuminumbus-singlebreakerschemewithbussectionalizingbreak-ersof345kV-Twostart-uptransformers-Emergencypowersupply(lowvoltage)IntheEPRIbaselinedesign,waterfromthecondensorswouldbecooledintwomechanicaldraftcoolingtowers,withmake-upwatercomingbypipeline.Thereis,ofcourse,thepotentialforopencyclecoolingusingacoolingpondwhichoffersapotentialcostsavings.However,duetothescopeofthisstudy,thiswasnotinvestigated.Theuseofnaturalwaterbodiesforonce-throughcoolingisgenerallycheaperthancoolingtowers.However,duetoenvironmentalconstraints,thiscoolingmethodisrestricted.SiteaccesscostsincludedintheEPRIplantdesignwerebaseduponare-motearea;accessoriesincluded15milesofrailroadandswitchingstation,and13milesofwaterpipeline.ThiswouldadequatelyrepresentaremotedevelopmentintheBelugaarea.8-10 TableB.6summarizesthecostestimateoftheEPRIplantin1976.Thecostin1976dollarsfora1000MWplantwasdeterminedtobe$566.6million.(iii)CostAdjustmentsUpdatedcostsfor1980weredevelopedusingtheHandy-Whitmanindices(54).TheHandy-Whitmanindicesarewidelyusedforcostupdating.Theyaredevelopedbi-annuallybyWhitman-RequardtandAssociatesandarebasedonextensiveutilityplantcostresearchineachofsixregionsoftheUnitedStates.TheHandy-WhitmanindicesusedforthisstudyarefortheRegion6-PacificNorthwestarea.TheyarerepresentedasaratiooftheJanuary1,1980dollarvaluestotheJanuary1,1976dollarvaluesforavarietyofplantcostestimates.The1976costwasthereforeupdatedtogivea1980dollarcostof$792million.Thiscostrepresentsthecostofa1000MWplantintheLower48andthereforeisrequiredtobescaledtoreflectthecostofaunitsizeapplicabletotheRailbeltregion.Twomethodswereconsideredinscalingthecost.ThefirstwasdevelopedfromEPRIresearchwhichreportedthatapproximately-54percentofthetotalconstructioncostwasattributabletothefirstunit(17).Thecostofasingle500MWunitwouldthusbe54percentofthecostofa1000MWplant,or$428million.Thecapacityscalingequationusedwas:CostofUnitACostofUnitB=(CapabilityofUnitA)exponent(CapabilityofUnitB)Thisequationwassolvedfortheexponentbysubstitutingthevariouscostsandcapabilities.Thisyieldedavalueof0.89whichissubstantiallygreaterthantheusual0.6value.However,asdiscussedinanarticleonthesubjectofcomputingeconomyofscalevalues(51),inflation,highin-terestratesandlengthenedscheduleshavenegatedtoalargedegreethe0.6economyofscaleandbroughttheexponentuptovaluesof0.79to0.86.Thiscomparesfavorablytothe0.85valueobtainedinanalysesconductedbyBattellefor200to500MWunits.Itisassumedthatthe0.85valueusedbyBattelleinpreviousstudiesisanaccuraterepresentationofthecur-renteconomyofscaleinpowerplantestimation.Consequently,thisvaluewasusedfortheplantcostsinthisstudy.TablesB.8,B.9andB.10reflectthisapplication.Forthe100MWplantthescalingfactorusedwas0.85ratherthanthe0.60suggestedbyBattelleforplantsinthe100to200MWrange.Applyingthe0.85factorresultsinamoreconservativefigureforthe100MWplantbyalmost$90milliondollars($111vs$199million).TheapplicationoftheestablishedLower48costtotheRailbeltsituationmusttakeintoaccountavarietyofotherfactors.Short-termadditionstoexistingcoal-firedplantsareaviablepossibilityforextensionofRail-beltgenerationcapability.OngoingstudiesintheFairbanksregiontoexpandexistingcoal-firedcapacityforelectricityanddistrictheating,althoughforasmallerplantcapacitythanthe100MWconsideredhere,haveshownthecostofnewmechanicalequipmentalonetobeapproximately1.77timesmorecomparedtoasimilarinstallationintheLower48.Thisresult,inadditiontoresearchbytheU.S.ArmyCorpofEngineersandB-ll Battelle,indicatesincreasesinLower48plantcostsintherangeof1.2to2.65fortheRailbelt.Additionally,duetothelimitationsofmostoptimizedproductioncostmodels,allowanceismadeforanumberoffuturesizeadditions;however,theadditionsaresite-constricted,allowingnovariabilityincapitalcostversussiteconditions.Reviewingthelong-termcoalproductionandusepotentialintheRailbeltindicatesthatlargescaledevelopmentatBelugaisagoodpossibility.Thisdevelopmentwouldentailexportoperationsandlocalgenerationusage.Therefore,todevelopandrepresenttoaproductioncostmodelanindica-tionoflikelysitedevelopmentandcost,theLower48capitalcostswereadjustedtorepresentaBeluga-siteddevelopment.Thisrepresentationinnowaydisallowsthepossibilityofexpansionorevensmallscaledevelop-mentofcoalpotentialatotherRailbeltlocations.Itdoes,however,servetorepresentanoverallRailbeltcoalpotentialcostforaremoteAlaskansituation.TheBelugacostfiguresshowninTablesB.8toB.10re-flecta1.8Alaskanadjustmentfactor,whichrepresentsthemiddlerangeofallRailbeltestimatesandissimilartothedevelopedBelugafactorreportedbyBattelle(3).InadditiontothedirectcostsshowninTablesB.8,B.9andB.10,acon-tingencyof16percent,10percentforutilitiesandotherconstructionfacilitiesand12percentforengineeringandadministrationwasadded.Interestof3percent,netofescalation,duringtheconstructionperiodofsixyearsforthe500and250MWplantsandfiveyearsforthe100MWplantwouldbeanaddedcost.(iv)OperatingCharacteristicsCoal-firedplantoperatingcharacteristicswhichareincorporatedinthegenerationplanninganalysisareheatrate,unitavailabilityandoperationandmaintenancecosts.Theheatrateselectedforthethreeplantsizesis10,500Btu/kWh,whichisconsistentwiththeEPRIplantdesign.Outagesforcoal-firedsteamplantsaretakenintoaccountintermsofscheduled(planned)andforcedoutagesasapercentoftime.Datapublish-edbytheEdisonElectricInstitute(EEl)indicatesaforcedoutageofap-proximately5.4percentforlargecoal-firedplants(41).Thisfigurewasroundedto5percenttorepresentforcedoutagesforstudypurposes.Sche-duledoutages,asreportedbyGVEAfortheirHealyplant,areinthe5.1to16.3percentrange.Anaverageof11percent,whichalsocorrelateswiththeEEldata,wasadoptedasthescheduledoutagerateforcoal-firedplantsforthisstudy.TheparametersgivenaboveforthermalgeneratingplantsaregiveninTableB.13.Operationandmaintenance(O&M)costsforuseingenerationplanningaredividedintotwocomponents:fixedcostsandvariablecosts(exclusiveoffuel).FixedO&Mcostsfortypicalu.S.plantsarereportedperiodicallyintheDOEpublication,SteamPlantConstructionandAnnualProductionExpenses(21).Trendsindicatedinthesereportsledtoadoptionofvaluesforfixedcostof0.50,1.05and1.30$yr/kwfor500MW,250MWand100MWplantsrespectively.VariablecostsintheDOEpublication(21)areshowntodecreasewithincreasingunitsize.Thevaluesusedinthisstudyare$1.40,$1.80and$2.20/yr/kWfor500MW,250MWand100MWplantsrespectively.B-12 (b)CombinedCycleAnumberoffactorshaverecentlyledtoanincreasedinterestincombinedcyclegeneratingplants,bothintheLower48andAlaska.Thesefactorsincluderisingfuelprices,increasingenvironmentalrequirementsandgreaterflexibilityformid-andbase-loadapplicationsdictatedbychang-ingsystemloadrequirements.TheseconditionshavepromptedtwoAnchorageutilities,AMLPDandCEA,tolooktocombinedcyclegenerationtomeettheirneeds.PresentlytherearetwocombinedcycleplantsinoperationinAlaska.Anoperationalunit,knownastheG.M.SullivanplantandownedbyAMLPD,con-sistsofthreeunitswhich,whenoperatingintandem,produceanetcapa-cityof140.9MW.AnotherplantunderconstructionforCEAandknownasBelugaNo.9unitwilladda60MWsteamturbinetothesystemsometimein1982.Thesetwounitsrepresentexpansionstoexistinggas-turbineplantsandareconsideredtobeessentiallyshort-termgenerationplanningcommit-mentsfortheRailbelt.Forthelongerterm,aunitcapacityof250MWfornewcombinedcycleplantswasconsideredtoberepresentativeofpotentialfutureadditionsintheRailbeltarea.ThisassumptionisbasedontrendsintheLower48andloadgrowthprojectionsinAlaska.Aheatrateof8500Btu/kWhwasadoptedbasedonAlaskanexperience.TheEPRIreportAF-610(18),wasusedasthebasisofcostestimatesforthistypeofplant.Asubstantialquantityofnaturalgascouldbeavailabletoutilitieswiththeimplementation oftheAlaskanNaturalGasPipeline.However,construc-tionofanaturalgaspipelinespurtosupplycombined-cycleinstallationsintheRailbeltregionisnotlikelyduringthecriticalstudyplanningperiodof1990-1995.AllgeneratingresourcesinFairbanksarecurrentlyfueledwithcoaloroil.Inaddition,despitethecloseproximityoftheBelugaregiontotheCookInletgasreserves,developmentatBelugawouldnotbepredicatedoncombinedcycleplants.Therefore,thepotentialinstallationofcombinedcycleplantswillmostlikelybelimitedtotheAnchoragearea.Thispremiseisbasedonthelocalelectricutilities'mostrecentgenerationexpansionprogramsandreadilyavailableCookInletnaturalgas.RecentexperienceincombinedcycleconstructioninAlaskahasbeenlimitedtosmallexpansionsofexistingfacilities.Forpurposesofthisstudy,itwasthereforenecessarytorelyonLower48costestimatesforlargerin-stallations,extrapolatedtoapplytoAlaskaconditions.Lower48costsfor250MWcombinedcyclegeneratingunitsaregiveninTableB.13.ThesecostswereobtainedfromGeneralElectricCorporationin1980dollars.Estimatesweremadeforcostsoffoundati~nsandbuildings,fuelhandlingfacilitiesandothermechanicalandelectricalequipment.Anadditionalcostof25percentofthecostofthegeneratingequipmenthasbeenincludedfortransportationofthebasicunittothePacificNorthwest.ThesecostswerecomparedtopriorcostestimatesofcombinedcyclepowerplantsinEPRI-AF-610andwerefoundtobeconsistent.UsinganAlaskanlocationadjustmentfactorof1.6recommendedbyBattelle(3),theaccountitemswereadjustedforaplantlocatedintheAnchoragearea.TransportationtoAnchoragewasassumedtobe25percentmorethantothePacificNorthwestcoast.ThismaybeslightlyhighfortransportationcoststoAlaska,however,consideringlimitednavigationperiodsandsizeB-13 sizeofthe250MWunits,itisbelievedtobeareasonableassumptionandwithinlimitsofaccuracyforstudycostestimates.Asforcoal-firedplants,indirectcostsof16percentforcontingency,10percentforconstructionfacilitiesandutilities,and12percentforengineeringandadministrationwereaddedtothedirectedcost.TableB.13summarizestheresultsoftheseestimates.Allowanceforfundsduringconstruction(AFDC)fortheseyearsisincludedinthistotal.Op-erationandmaintenance(O&M)costsforlargecombinedcycleplants,asre-portedinEPRl,AF-610(18)approximate$2.75/yr/kWforfixedO&Mand$0.30/MWhforvariableO&M.ThesewereadoptedforAlaskanapplication.BasedoninformationprovidedbyAMLPDfortheirG.M.Sullivancombinedcycleplant,scheduledoutageratesareapproximately11percent.Foralargerplantof250MW,basedonEEldata,a14percentscheduledoutageratewasselected.Aforcedoutagerateof6percentwasalsoconsideredappropriatebasedontheAMLPDandEEldata.Thecombined-cycleplantpar-ametersaresummarizedinTableB.13.(c)GasTurbinesGasturbinesarebyfarthemainsourceofthermalpowergeneratingre-sourcesintheRailbeltareaatthepresenttime.Thereare470.5MWofinstalledgasturbinesoperatingonnaturalgasintheAnchorageareaandapproximately168.3MWofoil-firedgasturbinesintheFairbanksarea(TableB.7).Lowinitialcostandsimplicityofconstructionandoperationinadditiontoavailablelowcostgashavemadegasturbinesveryattrac-tiveasaRailbeltgeneratingscource.Newoil-firedgasturbineswerenotconsideredinthisstudyprimarilybecauseofthepriceofdistillate.Thispricehasbeenhistoricallyhigherthannaturalgasandisexpectedtoremainso.Aunitsizeof75MWwasconsideredtoberepresentativeofamoderngasturbineplantadditiontotheRailbeltsystem.Thepossibilityofinstall-inggasturbineunitsatBelugawasnotconsidered,asthisdevelopmentisintendedprimarilyforcoal.Coalconversiontomethanolisapossibility;butthisconsiderationisbeyondthescopeofthisstudy.Thegasturbineplantsareassumedtohaveatwo-yearconstructionperiod(22).ThebaseplantcostswereobtainedfromtheGasTurbineWorldHand-book(19),whichlists"turnkey"bidsin1978dollarsforagasturbineprojectinAnchorage.TheseestimatesarequotedinTableB.14.Thesees-timateshadanestimatedheatrateof12,000Btu/kWh.Thecostswereesca-latedby13.7percentusingthedevelopedHandy-WhitmanindicestoJanuary,1980dollars.A10percentincreasewasincludedforconstructionfacili-tiesandutilitiesaswellasa14percentengineeringandadministrationfee(TableB.15).Theresultantcostof$25.80million(excludingAFDC)wasconsideredrepresentativeofthecostofgasturbineconstructionre-gardlessoflocationwithintheRailbelt.Potentiallyhighercostcould,however,beincurredforremoteAlaskanlocations.Operationandmaintenance(O&M)costsadoptedare$2.50/yr/kWand$0.30/MWhforthefixedandvariablecomponents.ThesevaluesreflectintermediatelevelsofO&McostsintheFMUS/GVEAUnitStudy(32).B-14 Threesourcesofdatawereconsultedforplannedandforcedoutagesofgasturbineunits;theEElreportandinformationfromAMLPDandGVEA.Sche-duledoutageratesof11to12percentandforcedoutageratesof3.8per-centappeartobevalidintheAlaskaarea.Gas-turbineparametersaregiveninTableB.12.(d)DieselsMostdieselplantsinoperationtodayarestandbyunitsorpeakinggenera-tionequipment.Nearlyallthecontinuousdutyunitshavebeenplacedonstandbyserviceforseveralyearsduetothehighoilpricesandtheconse-quenthighcostofoperation.Thelackofsysteminterconnectionandtheremotenatureoflocalizedvillageloadcentershasrequiredtheinstalla-tionofmanysmalldieselunits.Theinstalledcapacityofthesedieselunitsis64.9MW,andtheseunitsaresolelyusedforloadfollowing.Thehighcostofdieselfuelmakesnewdieselplantsexpensiveinvestmentsforallbutemergencyuse.Aunitsizeof10MWwasselectedtorepresentanadditionofasmallamountofstandbycapacityintheAlaskanRailbelt.Todevelopacapitalcostoftheseunits,threemanufacturers·quotesforgeneratingunitswereobtained:Six16cylinderunitstotalling10,685kWat900RPMat$5,050,000F.O.B.AdditionalcostswouldbeincurredfortransportationtoAlaska(10percentofgeneratingunits),controlsandbuildings/site.develop-menteAfourunit(2500kW/unit)dieselgeneratingplantat$3,000,000F.O.B.A$10,000/unittransportationcosttoAlaskawassuggestedaswellasadditionalcostsforpre-engineeredbuilding,foundations,controlsandelectricalequipment.-Ten100kWunitsplustwoforcontinuousduty,eachunitcosting$150,000,givingatotalcostfor12unitsof$1,800,000F.O.B.A$5,000/unittransportationcostwasassessedandadditionalcostsformechanicalcontrols.Alsoaddedtothecostofthegeneratingunitsareauxiliarymechanicalandfuelhandlingequipmentandelectricalsystem/switchyardcosts.Aconstructionperiodofoneyearwasassumedsincetheseplantsaremodu-larandquicktoassemble.Inaddition,contingencies(16percent),con-structionfacilitiesandutilities(10percent),engineeringandadminis-tration(14percent)areaddedtocosts.Anaveragecostof$7.67million1980dollars(excludingAFDC)wasadoptedandusedfortheentireRailbeltregionregardlessoflocationbasedonthemodularandrapidconstructiontechniquesassociatedwiththesesmalldieselunits.DieselO&McostsquotedintheWilliamsBrothersReportforGVEAandFMUS(32)areconsideredtypicalforsmalldieselunitsoperatinginAlaska.Fixedcostsof$O.50/yr/kWand$5.00/MWhforvariablecostsareusedinthisstudy.B-15 Dieselunitshavealow(1percent)scheduledoutagerate.ThisrateisbasedonEElutilityexperience.However,theEEldatacorrespondtounitsinlocationswherepartsandserviceareforthemostpartreadilyavail-able.CanadianElectricalAssociatesdataforremoteisolatedunitswithdifficultaccessforpartsandservicearefarworse.Alaskacouldbesomewherebetweentheseextremes,withheavydependenceonunitmanufac-turersandlocationgivingforcedoutagesratesofbetween4.0-5.0percent.Consequently,a 5percentratewasadoptedforthesystemplanningstudy.DieselparametersaresummarizedinTableB.12.B.3-EnvironmentalConsiderationsTheinvestigationofthermalalternativesforinclusionInproposedgenerationexpansionsequencesdealtwithgenericplanttypeswhichweregenerallynotsitespecific.Theunderlyingassumptionforinputwasthatenvironmentallyaccept-ablesitescouldbefoundwithintheRailbeltregion.Thus,theconcernadd-ressedwastheidentificationofmajorcostitemsincurredbynecessaryenviron-mentalprotectionmeasures.Themajorenvironmentalprotectioncostcomponentofcoal-fired,gasturbine,combinedcycle,anddieselunitswillbethatrequiredforairpollutioncontroltomeettheNationalNewSourcePerformanceStandards(NSPS).SitingofthermalplantsintheRailbeltregionmaybelimitedbythePreventionofSignificantDeterioration(PSD)standardsforClassI,II,andIIIairsheds.PlantslocatednearNationalParkswhicharedesignatedClassIwillbesubjecttothescrutinyoftheeffectsofitsemissionsonvisibilityandairqualitywithinthepark.ClassIIareasthatarenotpresentlyincompliancewithoneormoreoftheambientairqualitystandards(AnchorageandFairbanks)orthatareclosetoexceedingthePSDincrementfortheairshed(suchasValdez)maynotbeacceptablesitesforthermalplants.Otherenvironmentalcontrols,suchasthoserequiredforwateruse,effluentdischarge,solidwastedisposal,noisecontrolandconstructionactivities,areimportantwithrespecttothepresentqualityoftheAlaskanenvironment.Thesefactors,althoughnotsignificantatthistimeforcostestimatingpurposes,wouldhavetobeconsideredintheevaluationofanyplantsiting.(a)AirQualityRequirementsThecostofairpollutioncontrolequipmentisbasedonsatisfactionofthenationalNSPSandNationalAmbientAirQualityStandards(NAA~S)(36).ItisassumedthatcompliancewithNSPSandNAAQSforthefinalsiteselectionforspecificfacilitieswillassurecompliancewiththePreventionofSig-nificantDeterioration(PSD)aspectsofairqualityregulation.TheStateofAlaskahasadoptedtheNationalAmbientAirQualityStandards,withad-ditionofastandardforreducedsulfurcompounds(36,37).TheStatemayalsorequiremeasuresforcontroloficefog(38).ThreeNewSourcePerformanceStandardscovertheplanttypesunderconsid-eration.TheNSPSforElectricUtilitySteamGeneratingUnitsisapplic-abletocoal-firedstearnunits.Specificstandardsaresetforcontrolofsulfurdioxide(S02),particulate,andnitrogenoxides(NOx)'Forthecoal-firedunits,theuseofhighlyefficientcombustiontechnologyis8-16 acceptedforcontrolofNOx'FluegasdesulfurizationisrequiredforS02removal,anddryscrubbertechnologyisrecommendedbyEPAforusewithlowsulfurfuel.Lowsulfurfuelisgenerallyconsideredtohaveasulfurcontentlessthan3lb/millionBTUorlessthanapproximately1.5percentsulfurbyweightincoal.TypicalAlaskancoalshavesulfurcon-tentsofaround1.5percentbyweight.Drytechnologyisappropriatealsoforreductionofpotentialicefogproblems.BaghousesarepreferredbyEPAforremovalofparticulatesinfacilitiesburninglowsulfurfuel.Pollutioncontrolforgasturbineunitsandforcombinedcycleunitsburn-inggasisdesignatedbytheNewSourcePerformanceStandardsforgastur-bines.InstallationofgasturbineunitsrequireswetcontroltechnologysuchaswaterorsteaminjectionforcontrolofNOxemissions.Turbinesusingtheinjectionprocess,however,areexemptfrommeetingtheNOxemissionsstandardsduringperiodswhenicefogisdeemedatraffichazard.S02emissionsarelimitedbylimitationsonfuelsulfulcontent.NSPSforStationaryInternalCombustionEngineswhichapplytotheproposeddie-selunitsrequireNOxcontrol.ReductionofNOxemissionswillbeachievedbyanefficientfuelinjectionprocess.NewpollutionsourcesmustmeetthePSDrequirementsforClassI,II,andIIIairsheds(39).MostareasofthestatearedesignatedClassIIareas(40)inwhichimplementationofNSPStechnologieswillbesufficienttosatisfythePSDincrement.Thereareseveralexceptionstothisstatus(40).Mt.McKinleyNationalParkisdesignatedasaClassIarea.Aplantlocat-edinthevicinityoftheParkwouldbesubjecttotherestrictionsbasedontheeffectsofitsemissionsonvisibilityandairqualitywithinthepark.AnchorageandFairbanks-NorthPoleurbanareasarepresentlytheonlyClassIIareasnotincompliancewithoneormoreofambientairqual-itystandards.ValdezisclosetoexceedingthePOSincrementallowedfortheairstand.Compliancewithstricterregulationsinanyofthesesensitiveareascouldincurhigherpollutioncontrolcosts,orcouldeffectivelyresultinbarr-ingthedevelopmentofathermalplantinthatarea.Itislikelythatnewthermalplantswillnotbelocatedintheseareasifthecostofadditionalpollutioncontrolequipmentsubstantiallyaffectsthecostofenergysup-pliedtotheconsumer.Thesesitinglimitations,however,barelylimitthenumberofpossibleplantlocationswithintheRailbelt.Therefore,"theas-sumptionofcompliancewithNSPSisbelievedtobeappropriateforderiva-tionofairpollutioncontrolcosts.(b)OtherRequirementsThecostsforotherenvironmentalcontrolswerealsoincludedincostesti-mates.Thesecontrolsaremandated~nationalandstatewaterdischargestandards,solidwastedisposalstandardsandoccupationalhealthandsafetystandards.Thesecontrolswillhavethegreatestrelativeimpactonthecostofcoal-firedplantscomparedtotheotherthermalplanttypes.Thisisduetothelargepermanentstaffrequiredatcoalplantsforcoalhandlingandplantoperationsandmaintenance,andtothetreatmentfacili-tiesrequiredforfluegasdesulfurizationwastes.However,comparedtothecostsofairpollutioncontrol,thesecostsareofminorsignificance.B-17 LISTOFREFERENCES(1)Abegg,F."BurningCoalinAlaska- AWinterExperience",ASME,1980.(2)AlaskanDepartmentofCommerceandEconomicDevelopment,AlaskaCoalandthePacific,Juneau,Alaska,September,1977.(3)BattellePacificNorthwestLaboratories,AlaskanElectricPower;AnAnalysisofFutureRequirementsandSupplyAlternativesfortheRailbeltRegion,March,1978.(4)EngineeringNewsRecord,"ConstructionisUnderwayonAlaska-CanadaGasline",August21,1980,P.18.(5)Erickson,GreggandBoness,Frederick.AlaskaCoalandAlaskaPowerAlternativesfortheRailbelt,May,1980.(6)ExecutiveOfficeofthePresident,EnergyPolicyandPlanning,DecisionandReporttoCongressontheAlaskaNaturalGasTransportationSystem,September,1977.(7)rCFIncorporated.AReviewofAlaskaNaturalGasTransportationSystemIssues;FERC,EJ-78-C-01-6395,May,1979.(8)JensenAssociatesInc."TheMarketOutlookforAlaskanNaturalGas,"September,1979.(9)U.S.DepartmentofEnergy,CostandQualityofFuelsforElectricUtilityPlants.FPCFormNO.423,DOE/EIA-0075(80/04),June1,1980.(10)U.S.DepartmentofEnergy,"RecommendationtothePresidentonANGTS,"May1,1977.(11)TheAlaskaEconomyYear-EndPerformanceReport,AlaskaDepartmentofCommerceandEconomicDevelopment,1979.(12)AlaskaOilandGasConservationCommissionStatisticalReport,1978.(13)StateofAlaska,DepartmentofNaturalResources,DivisionofMineralsandEnergyManagement,IIHistoricandProjectedDemandforOilandGasinAlaska1972-1995,IIApri1,1977.(14)TheEnergyReport,Vol.No.3,FairbanksNorthStarBorough,CommunityInformationCenter,September,1980.(15)Rao,P.O.andWolff,ErnestN.,"CharacterizationandEvaluationofWashabilityofAlaskanCoals."UniversityofFairbanksforDOEGrantNo.G0166212,May,1978.B-18 LISTOFREFERENCES(Cont1d)(16)U.S.DepartmentofEnergy,OfficeofEnvironmentalAssessments,DivisionofEnergyandPower.AlaskaRegionalEnergyResourcesPlanningProject,Phase2,Coal,HydroelectricandEnergyAlternatives;Volume1BelugaCoalDistrictAnalysis.PreparedbyAlaskaDepartmentofCommerceandEconomicDevelopment,1980.(17)Coal-FiredPowerPlantCapitalCostEstimates-EPRIAF-342(SOA76-329FinalReport,December,1977.(18)CombinedCyclePowerPlantCapitalCostEstimates-EPRIAF-610(SOA77-402)FinalReport,December,1977.(19)GasTurbineWorldHandbook-1978,PequotPub.Vol.4,1979-80.(20)1978FairbanksEnergyInventory-CommunityInformationCenterSpecialReportNo.4,FairbanksNorthStarBorough,July,1979.(21)U.S.DepartmentofEnergy,Steam-ElectricPlantConstructionCostandAnnualProductionExpenses1976,August,1978.(22)U.S.DepartmentofEnergy,GasTurbineElectricPlantConstructionCostandAnnualProductionExpenses-1976,EIA-0180,April,1979.(23)Phung,DoarL.,AMethodforEstimatinEscalationandInterestDurinConstructionEDC&IDC.ORAU/IEA-78-6M,April,1978.(24)ElectricalWorldDirectoryofElectricUtilities-1979-8087thEdition.(25)Manual-U.S.ArmyCorpsofEngineers,Portland,1979.(26)Personalcommunication,re:SusitnaHydroelectricProject-Task6,CostEstimating.September,1980.(27)BechtelCorporation,ExecutiveSummary,PreliminaryFeasibilityStudy,CoalExportProgram,Bass-Hunt-WilsonCoalLeases,ChuitnaRiverField,Alaska.April,1980.(28)Hennigan,Brian0.,CookInletCoal:EconomicsofMiningandMarineSlurryTransport,MastersThesis,UniversityofWashington,Seattle,Washington,1977•(29)Olsen,Marvin,etal.,1979.BelugaCoalFieldDevelopment:SocialEffectsandManagementAlternatives.PreparedforAlaskaDivisionofEnergyandPowerDevelopment,DepartmentofCommerceandEconomicDevelopment,Anchorage,AlaskaandtheU.S.DepartmentofEnergy,OfficeofTechnologyImpacts,RegionalAssessmentDivision,Washington,D.C.byPacificNorthwestLaboratory,Richland,Washington,BattelleHumanAffairsResearchCenters,Seattle,Washington,andCH2MHill,Anchorage,Alaska.PNL-RAP-29UC-11.B-19 LISTOFREFERENCES(Cont'd)(30)BattellePacificNorthwestLaboratory,DraftFinalReport,~elugaCoalMarketStudies,fortheStateofAlaska,OfficeoftheGovernor,DivisionofPolicyDevelopmentandPlanning,September,1980.(31)FederalEnergyRegulatoryCommission(FERC)FormNo.12,PowerSystemStatementsfor(a)AnchorageMunicipalLightand PowerDepartment(AMLU),(b)ChugachElectricAssociation(CEA),(c)FairbanksMunicipalUtilitySystems(FMUS),(d)HomerElectricAssociation(HEA),and(e)GoldenValleyElectricAssociation(GVEA),December31,1979.(32)WilliamtirothersEngineeringCompany,ReportonFMUSandGVEASystems,1978.(33)AlaskaDepartmentofRevenue,PetroleumRevenueDivision,PetroleumProductionRevenueForecast,QuarterlyReport,March,1980.(34)AlcanPipelineCompany,AlcanPipelineProject,48-InchAlternativeProposal,March,1977.(35)Markle,Donald,ofOITGeo-HeatUtilizationCenter,GeothermalEnergyinAlaska:SiteDataBaseandDevelopmentStatus,fortheU.S.DepartmentofEnergy,April,1979.(36)TheBureauofNationalAffairs(BNA),Incorporated,BNAPolicyandPracticeSeries;AirPollutionControl,Section101;AmbientAirQualityStandards,Section111;StatePolicies,Section121,NewSourcePerformanceStandards,copyright1980.(37)StateofAlaska,AlaskaAdministrativeCode,Title19,Cnapter50.050(d).(38)StateofAlaska,AlaskaAdministrativeCode,Title18,Chapter50.090,IceFogLimitations.(39)StateofAlaska,AlaskaAdministrativeCode,Title18,Chapter50.020,AmbientAirQualityStandards.(40)StateofAlaska,AlaskaAdministrativeCoae,Title18,Chapter50.u21,StateAirwualityClassifications.(41)EdisonElectricInstitute(tEl),"ReportonEquipmentAvailabilityforthe10-yearPeriod1968-1978",1979.(42)PersonalcommunicationwithMr.HankNicholsofAnchorageMunicipalLightandPowerDepartment,September,1980.(43)PersonalcommunicationwithMr.LarryColpofFairbanksMunicipalUtilitiesSystem,September,1980.B-20 LISTOFREFERENCES(Cont'd)(44)PersonalcommunicationwithMr.WoodyBaker,GoldenValleyElectricAssociationProductionSuperintendent,September,1980.(45)U.S.DepartmentofEnergy,OfficeofConservationandSolarEnergy,FederalEnergyManagementandPlanningPrograms;MethodologyandProceduresforLifeCycleCostAnalysesAverageFuelCosts,TheFederalRegister,Tuesday,October7,1980.(46)PersonalcommunicationwithDr.CharlesLogsdan,AlaskaStateDepartmentofRevenue,December,1980.(47)PersonalcommunicationwithMr.SchandlerofSuperiorProducts,Springfield,Ohio,September,1980.(48)PersonalcommunicationwithBelyeaCompany,JerseyCity,NewJersey,September,1980.(49)PersonalcommunicationwithMr.MarshallofCumminsInternationalDiesel,Baltimore,Maryland,September,1980.(50)BattellePacificNorthwestLaboratory,BelugaCoalMarketStudyfortheStateofAlaska,OfficeoftheGovernor,December,1980.(51)Comtois,WilfredH.,"EconomyofScaleinPowerPlants",PowerEngineering,August,1977,p.51-53.(52)Budwani,RameshN.,"PowerPlantCapitalCostAnalysis",PowerEngineering,May,1980,p.62-70.(53)BattellePacificNorthwestLabortory,CookInletNaturalGas;FutureAvailabilityandPriceForecastsfortheStateofAlaska,OfficeoftheGovernor,February,1981.(54)Handy-Whitman,CostIndexforHydropowerProductioninthePacificNorthwest,1978.8-21 Table B.1 -ALASKAN RAILBELT COAL DATA 1 Approximate Heatmg Reserves 0'0'0'0'Value 0''"'"'"'"'0 ASTM million Moisture Volatile Fixed Ash Btu/lb 0'%0'0'Sulfur'"'0 '"Coal Field Rank tons (range)Matter Carbon (range)(range)C H N 0 (range) Beluga 2400 (12-33)--(3-25)(7200-----(0.2) 8900) Water Fall Sub Bit C 20.56 36.62 34.68 8.14 8,665 49.9 6.0 0.56 35.2 0.15 Yentna /12 Lower Lignite 29.80 38.26 28.61 3.33 7,943 45.2 6.8 0.53 44.1 0.11 Kenai Cabin Sub Bit C 23.01 35.63 32.71 8.65 8,028 47.2 6.1 0.62 37.2 0.23• Nenana Sub Bit 2000 (17-27)--(3-13)(7500--- --(0.1-0.3) 9400) Poker Flat 114 Sub Bit C 25.29 32.51 32.55 9.85 7,779 45.3 6.3 1.10 37.1 0.33 Poker Flat 116 Mid Sub Bit C 25.23 35.71 31.40 7.66 8,136 46.1 6.3 0.60 39.2 0.12 Moose Seam'Sub Bit C 21.42 36.62 34.88 7.68 8,953 51.7 6.3 0.81 33.3 0.15 Caribou Seam Sub Bit C 21.93 35.88 32.85 9.34 8,567 49.4 6.1 0.69 34.3 0.13 /12 Seam Sub Bit C 26.76 33.12 32.25 7.87 7,966 46.4 6.4 0.63 38.5 0.17 Jarvis Creek Sub Bit c 20.58 36.20 34.16 9.06 8,746 49.8 5.8 0.86 33.4 1.05 Matanuska 100 (2-9)--(4-21 )(10,300-- -- - (0.2-1.0) (limited)14,000) Castle Mountain Uv Ab 1.78 28.23 52.20 17.78 12,258 69.3 4.7 1.60 6.3 0.46 Premier Uv Bb 5.87 35.73 43.96 14.44 11,101 63.6 5.1 1.60 15.3 0.35 Kenai Sub Bit C 300 (21-30)--(3-22)(6500-----(0.1-0.4 ) 8500) Notes: (1)Proximate and ultimate analysis TableB.2-ALASKANGASFIELDSGas(billioncubicfeet)Location/fieldNorthSlope:PrudhoeBayEastUmiatKavikKemikSouthBarrow2TOTAL:CookInlet:AlbertKaloaBeaverCreekBelugaBirchHillFallsCreekIvanRiverKenaiLewisRiverMcArthurRiverMoquawkieNicolaiCreekNorthCookInletNorthForkNorthMiddleGroundShoalSterlingSwansonRiverWestForelandWestForkTOTAL:Notes:RemainingReserves129,000UnknownUnknownUnknown2529,025+Unknown250767208051313Unknown78None171074201252330012074189+ProductDestinationorFieldStatusPipelineconstructiontoLower48underwayShut-inShut-inShut-inBarrowresidential&commercialusersShut-inLocalBelugaRiverPowerPlant(CEA)Shut-inShut-inShut-inLNGPlant,Anchorage&KenaiUsersShut-inLocalFieldAbandonedGranitePt.FieldLNGPlantShut-inShut-inKenaiUsersShut-inShut-inShut-in(1)Recoverablereservesestaimedtoshowmagnitudeoffieldonly.(2)Producing (1)Recoverablereservesestaimedtoshowmagnitudeoffieldonly.(2)ProducingTableB.3-ALASKANOILFIELDSLocation/FieldNorthSlope:PrudhoeBay2SimpsonUgnuUmiatTOTALCookInlet:BeaverCreekGranitePointMcArthurRiverMiddleGroundShoalRedoubtShoalSwansonRiverTradingBayTOTALNotes:RemainingReserves1Oil(millionbarrels)8,375UnknownUnknownUnknown8,375+12111836None224198+ProductDestinationorFieldStatusPipelinetoValdezShut-inShut-inShut-inRefineryDriftRiverTerminalDriftRiverTerminalNikiskiTerminalFieldAbandonedNikiskiTerminalNikiskiTerminal TableB.4-ALASKANRAILBELTFUELPRICES(1980)FuelCoal1NaturalGas2OilSource/UseHealy/Mine-Mouth(GVEA)Healy/Fairbanks(FMUS)AverageLower48DOERegion10DOEU.S.AverageKenai-CookInlet/AnchorageUtilitiesAMLPDCEA:BelugaOtherAverageCookInlet/LNGexporttoNikiskiAverageLower48DOERegion10DOEU.S.AveragePrudhoeBay/FairbanksUtilities:GVEAFMUSCost$80/MMBTU1.251.401.351.551.461.000.241.040.344.50-4.651.984.893.583.454.01References( )&(( )&((9)June1980(45)October1980(45)October1980(31)(9)June1980(9)June1980(9)June1980(46)(9)June1980(45)October1980(45)October1980(31)(32)Notes:AverageLower48DOEU.S.Average5.44(9)June19804-63-4.93(45)October1980(1)HealyCoal=8,500Btu/lb(2)NaturalGas=1,005Btu/cf TableB.5-SUMMARYOFALASKANFUELOPPORTUNITYVALUESAlaskanOpportunityMarketPriceTransportCostValueFuelMarketVia$/MMBTU$/MMBTU$/MMBTUCoalPacificNWbarge1.550.501.05Lower48barge1.460.630.83JapanbargeN/AN/A1.33JapanPlacer-AmexN/AN/A1.33JapanbargeN/AN/A1.00-1.30JapanB-H-WN/AN/A1.00-1.30NaturalRegion10LNG-tanker4.892.502.39GasRegion10Pipelinespur4.891.972.92Lower48LNG-tanker3.582.501.08Lower48Pipelinespur3.581.9711.61JapanLNG-tanker4.50-4.653.001.50-1.65OilLower48Pipeline-tankerN/AN/A4.00Notes:(1)estimated Table B.6 -GENERATING UNITS WITHIN THE RAILBELT -1980 Heat Rate Minimum Maximum Fuel RetirementRaUbeltStationUnitUnitInstallationInstalled Utility Name /f Type Year (8TU/kWH)Capacity Capacity Capacity Type Year (MW)(MW) (MW) Anchorage AMLPD 1 GT 1962 15,000 14 2 15 NG 1992 Municipal AMLPD 2 GT 1964 15,000 14 2 15 NG 1994 Light &Power AMLPD 3 GT 1968 14,000 15 2 20 NG 1998 Department AMLPD 4 GT 1972 12,000 28.5 2 35 NG 2002 (AMLPD)G.M.Sullivan 5,6,7 CC 1979 8,500 140.9 NA NA NG 2009 Chugach Beluga 1 GT 1969 13,742 15.1 NA NA NG 1998 Electric Beluga 2 GT 1968 13,742 15.1 NA NA NG 1998 Association Beluga 3 GT 1973 13,742 53.5 NA NA NG 2003 (CEA)Beluga 4 GT 1976 13,742 9.3 NA NA NG 2006 Beluga 5 GT 1975 13,742 53.5 NA NA NG 2005 Beluga 6 GT 1976 13,742 67.8 NA NA NG 2006 Beluga 7 GT 1978 13,742 67.8 NA NA NG 2008 Bernice Lake 1 GT 1963 23,440 8.2 NA NA NG 1993 2 GT 1972 23,440 19.6 NA NA NG 2002 3 GT 1978 23,440 24.0 NA NA NG 2008 International 1Station1GT196539,9731 14.5 NA NA NG 1995 2 GT 1975 39,973 1 14.5 NA NA NG 1995 3 GT 1971 39,973 18.6 NA NA NG 2001 Knik Arm 1 GT 1952 28,264 14.5 NA NA NG 1985 Copper Lake 1 HY 1961 --15.0 NA NA --2011 Golden Valley Healy 1 ST 1967 11,808 25.0 7 27 Coal 2002 Electric 2 IC 1967 14,000 2.7 2 3 Oil 1997 Association North Pole 2 GT 1976 13,500 64.0 5 64 Oil 1996 (GVEA)2 GT 1977 13,000 64.0 25 64 Oil 1997 Zehander 1 GT 1971 14,500 17.65 10 20 Oil 1991 2 GT 1972 14,500 17.65 10 20 Oil 1992 3 GT 1975 14,900 2.5 1 3 Oil 1995 4 GT 1975 14,900 2.5 1 3 Oil 1995 5 IC 1970 14,000 2.5 1 3 Oil 2000 6 IC 1970 14,000 2.5 1 3 Oil 2000 7 IC 1970 14,000 2.5 1 3 Oil 2000 8 IC 1970 14,000 2.5 1 3 Oil 2000 9 IC 1970 14,000 2.5 1 3 Oil 2000 10 IC 1970 14,000 2.5 1 3 Oil 2000 Table B.6 (Continued) Railbelt Station Unit Unit Insta1lation Heat Rate Installed Minimum Maximum Fuel Retirement Utility Name //Type Year (BTU/kWH)Capacity Capacity Capacity Type Year (MW)(MW)(MW) Fairbanks Chena 1 ST 1954 14,000 5.0 2 5 Coal 1989 Municipal 2 ST 1952 14,000 2.5 1 2 Coal 1987 Utiltiy 3 ST 1952 14,000 1.5 1 1.5 Coal 1987 System (FMUS)4 GT 1963 16,500·7.0 2 7 Oil 1993 5 ST 1970 14,500 20.0 5 20 Coal 2005 6 GT 1976 12,490 23.1 10 29 Oil 2006 FMUS 1 IC 1967 11,000 2.7 1 3 Oil 1997 2 IC 1968 11,000 2.7 1 3 Oil 1998 3 IC 1968 11,000 2.7 1 3 Oil 1998 Homer Elec.Homer= Association Kenai 1 IC 1979 15,000 0.9 NA NA Oil 2009 (HEA)Pt.Graham 1 IC 1971 15,000 0.2 NA NA Oil 2001 Seldovia 1 IC 1952 15,000 0.3 NA NA Oil 1982 2 IC 1964 15,000 0.6 NA NA Oil 1994 3 IC 1970 15,000 0.6 NA NA Oil 2000 Matanuska Talkeetna 1 IC 1967 15,000 0.9 NA NA Oil 1997 Elec.Assoc. (MEA) Seward SES 1 IC 1965 15,000 1.5 NA NA Oil 1995 Electric System (SES)2 IC 1965 15,000 1.5 NA NA Oil 1995 Alaska Eklutna -HY 1955 --30.0 NA NA --2005 Power Administration (APAd) TOTAL 943.6 Notes: GT =Gas turbine CC =Combined cycle HY =Conventional hydro IC =Internal Combustion ST =Steam turbine NG =Natural gas NA =Not available (1)This value judged to be unrealistic for large range planning and therefore is adjusted to 15,000 for generation planning studies. TABLEB.7-EXISTINGGENERATINGCAPACITYINTHERAILBELTREGIONNo.TypeUnitsCapacity(MW)Coal-firedsteam554.0Naturalgasgas-turbines(Anchorage)18470.5Oil-firedgasturbines(Fairbanks)6168.3Diesels2164.9Combinedcycle(naturalgas)140.9Hydro245.0TOTAL53943.6MW TABLEB.8-1000MWCOAL-FIREDSTEAMPLANTCOSTESTIMATE-LOWER48$MIL[IONSHandy-WhitmanAccount/Item1976Adjustment198010Concrete22.40547/39431.1020Civil/Structural/Architectural21,22,24Structural&M1SC.Iron&Steel23.70559/39733.3725Architectural&Finish11.90500/36116.7626Earthwork23.70500/36132.8228SiteImprovements14.80500/36120.5030SteamGenerators119.70571/407167.9341TurbineGenerators48.40413/29368.2242MainCondenser&Auxiliaries4.20518/3616.0343RotatingEquipment,Ex.T/G12.80518/36118.3644Heaters&Exchangers3.70518/3615.3145Tanks,Drums&Vessels1.50518/3612.1546WaterTreatment/ChemicalFeed2.40518/3613.4447Coal/Ash/FGDEquipment47.1CoalOnloadlngEqulpment3.50461/3384.7747.2CoalReclaimingEquipment3.40461/3384.6347.3AshHandlingEquipment1.40461/3381.9047.4ElectrostaticPrecipitators61.30461/33883.6047.6FGDRemovalEquipment87.90461/338119.8847.8Stack(Lining,Lights,etc.)5.20461/3387.0948OtherMechanicalEquiEmentIncl.Insulatlon&agglng9.70518/36113.9249Heatin~EVentilating,AirCondlioning1.70518/3612.4350Piping44.60629/42266.4760Control&Instrumentation11.10461/32215.4170ElectricalEruipment(Switchgear!ransformers/MCCs/Fixtures)11.30461/33215.6980ElectricalBulkMaterials81,82,83CableTray&Conduit11.60173/12316.3184,85,86Wire&Cable13.40173/12318.85Switchyard11.30173/12315.89CONSTRUCTIONCOSTTOTAL$566.60$792.82 TABLEB.9-500MWCOAL-FIREDSTEAMCOSTESTIMATES$MI [ [ION5(1980)ACCOUNT/ITEM[ower48Beluga10-20Civil/Structural/Architectural$72.66$130.7930-46MechanicalEquipment146.57263.8247Coal/Ash/FGD131.52236.7348-60OtherMechanical53.0495.4770-80ElectricalEquipment36.0564.89CONSTRUCTIONCOSTTOTAL:$439.84$791.70Contingency(16%)70.37126.67Subtotal510.21918.37ConstructionFacilities/Utilities(10%)51.0291.84Subtotal561.231010.20Engineering&:Administration(12%)67.35121.23TOTAL(EXCLUDINGAFDC)$628.57$1131.43 TABLEB.10-250MWCOAL-FIREDSTEAMCOSTESTIMATESACCOUNT/ITEM10-20Civil/Structural/Architectural30-46MechanicalEquipment47Coal/Ash/FGD48-60OtherMechanical70-80ElectricalEquipmentCONSTRUCTIONCOSTTOTALContingency(16%)SubtotalConstructionFacilities/Utilities(10%)SubtotalEngineering&Administration(12%)$MIL[ION5(1980)Lower48Beluga$39.23$70.6179.15142.4777.52139.5328.6551.579.4635.02$244.01$439.20283.05509.47311.35560.41TOTAL(EXCLUDINGAFDC)$348.71$627.65 TABLEB.11-100MWCOAL-FIREDSTEAMCOSTESTIMATESACCOUNT/ITEM10-20Civil/Structural/Architectural30-46MechanicalEquipment47Coal/Ash/FGD48-60OtherMechanical70-80ElectricalEquipmentCONSTRUCTIONCOSTTOTALContingency(16%)SubtotalConstructionFacilities/Utilities(10%)SubtotalEngineering&Administration(12%)$MIL[ION5(1980)Lower48Beluga$21.19$38.1442.7476.9322.0839.7415.4727.8510.5018.90$111.98$201.56129.89233.80142.88257.19TOTAL(EXCLUDINGAFDC)$160.03$288.05 TABLEB.12-250MWCOMBINEDCYCLEPLANTCOSTESTIMATES$MI [[IoN 5(1980)[ower48Beluga2.834.535.639.0037.5060.001.402.245.288.4511.7918.869.3818.7573.81121.8385.61141.3494.17155.47ACCOUNT/ITEM20Civil/Structural/Architectural21,22,23Buildings/Structures26,28FoundationsSiteWork40Mechanical41-47GeneratingUnits45FuelHandling48OtherMechanical70/80ElectricalEquipment100Transportation:(25%)(41-47total)PacificNW(50%)(41-47total)AnchorageCONSTRUCTIONCOSTTOTALContingency(16%)SubtotalConstructionFacilities/Utilities(10%)SubtotalEngineering&Administration(12%)TOTAL(EXCLUDINGAFDC)$105.47$174.13 TABLE B.13 -SUMMARY OF THERMAL GENERATING RESOURCE PLANT PAR~METERS I'TJ\N T T Y P E CO~[-FIRED STEAM COMBINED GAS Parameter CYCLE TURBINE DIESEL 500 MW 250 MW 100 MW 250 MW 75 MW 10 MW Heat Rate (Btu/kWh)10,500 10,500 10,500 8,500 12,000 11,500 O&M Costs Fixed O&M ($/yr/kW)0.50 1.05 1.30 2.75 2.75 0.50 Variable O&M ($/MWH)1.40 1.80 2.20 0.30 0.30 5.00 Outa~ Planned Outages (%)11 11 11 14 11 1 Forced Outages (%)5 5 5 6 3.8 5 Construction Period (yrs)6 6 5 3 2 Start-up Time (yrs)6 6 6 4 4 Total Capital Cost ($million) Railbelt:---175 26 7.7 Beluga:1,130 630 290 Unit Capital Cost ($/kW)1 Railbelt:- --728 250 778 Beluga:2473 2744 3102 Notes: (1)Including AFDC at 0 percent escalation and 3 percent interest. TABLEB.14-GASTURBINETURNKEYCOSTESTIMATE1TurnkeyInstalledBidsCapacity($million1978)6313.957518.107718.807814.32Notes:(1)Source:Reference(19) TABLEB.15-GAS75MWGASTURBINECOSTESTIMATEItemTurnkeyCostConstructionfacilities/Utilities(10%)EngineeringandAdministration(14%)TOTAL(EXCLUDINGAfDC)Notes:Cost($million1978)($million1980)118.1020.582.063.1625.80(1)AdjustedbyHandy-WhitmanCostIndicesforSteamPlants(258/227) APPENDIXC -ALTERNATIVEHYDROGENERATINGSOURCESTheanalysisofalternativesitesfornon-Susitnahydropowerdevelopmentfollow-edtheplanformulationandselectionmethodologydiscussedinSection1.4ofVolumeIandAppendixA.Thegeneralapplicationofthefive-stepmethodology(FigureA.1)fortheselectionofnon-SusitnaplansispresentedinSection6ofthisreport.Additionaldataandexplanationoftheselectionprocessarepre-sentedinmoredetailinthisAppendix.Thefirststepintheplanformulationandselectionprocessistodefinetheoverallobjectiveoftheexercise.Forstep2oftheprocess,allfeasiblesitesareidentifiedforinclusionintothesubsequentscreeningprocess.Thescreeningprocess(step3)eliminatesthosesiteswhichdonotmeetthescreen-ingcriteriaandyieldscandidateswhichcouldberefinedtoincludeintotheformulationofRailbeltgenerationplans(step4).Detailsofeachoftheaboveplanningstepsaregivenbelow.TheobjectiveoftheprocessistodeterminetheoptimumRailbeltgenerationplanwhichincorpor-atestheproposednon-Susitnahydroelectricalternatives.C.1-AssessmentofHydroAlternativesNumerousstudiesofhydroelectricpotentialinAlaskahavebeenundertaken.Thesedateasfarbackas1947,andwereperformedbyvariousagenciesincludingthethenFederalPowerCommission,theU.S.ArmyCorpsofEngineers(COE),theUnitedStatesBureauofReclamation(USBR),theUnitedStatesGeologicalSurvey(USGS)andtheStateofAlaska. Asignificantamountoftheidentifiedpoten-tialislocatedintheRailbeltregion,includingseveralsitesinthe SusitnaRiverBasin.ReviewoftheabovestudiesandinparticulartheinventoriesofpotentialsitespublishedintheU.S.ArmyCorpsofEngineersNationalHydropowerStudy(1)andtheAlaskaPowerAdministration(APAd)IIHydroelectricAlternativesfortheAlaska-Railbeltll(2)identifiedatotalof91potentialsites(FigureC.1).Allofthesesitesaretechnicallyfeasibleand,understep2oftheplanningprocess,wereidentifiedforinclusioninthesubsequentscreeningexercise.C.2-ScreeningofCandidateSitesThescreeningprocessforthisanalysisrequiredtheapplicationoffouritera-tionswithprogressivelymorestringentcriteria.(a)FirstIterationThefirstscreenoriterationdeterminedwhichsitesweretechnicallyinfeasibleornoteconomicallyviableandrejectedthesesites.Thestan-dardforeconomicviabilityinthisiterationwasdefinedasenergyproductioncostlessthan50millsperkWh,basedoneconomicparameters.ThisvalueforenergyproductioncostwasconsideredtobeareasonableupperlimitconsistentwithSusitnaBasinalternativesforthisphaseoftheselectionprocess.C-l CostdataprovidedinpublishedCOEandAPAdreportswereupdatedtorepre-sentthecurrentlevelofeconomicsinhydropowerdevelopmentforatotalof91sitesinventoriedwithintheRailbeltRegion.AsdiscussedinSection8,annualcostswerederivedonthebasisofa 3percentcostofmoney,netofgeneralinflation.ConstructioncostsweredevelopedbymakinguniformthefieldcostsprovidedintheCOEandAPAdreports.Thiswasnecessaryasthetwoagenciesuseddifferentlocationfactorsintheirestimates,toaccountforhigherpricelevelsinAlaska.Contingenciesof20percentandengineering-administrationadjustmentsof12to14percentwereaddedtofinallyyieldtheprojectcost.Projectcostsweresubse-quentlyupdatedtoaJuly1,1980pricelevelbasedontheIIHandy-WhitmanCostIndexforHydropowerProductioninthePacificNorthwestll(3).Usingupdatedprojectcostsaswellasaseriesofplantsize-dependenteconomicfactorspreliminarilyselectedfortherougheconomicscreening,theaverageannualproductioncostsinmills/kWhwereestimatedforthe91sites.Typicalfactorsconsideredwereconstructionperiod,annualinvest-mentcarryingcharges,andoperationandmaintenanceexpenditures.Plantcapacityfactorsrangedfrom50to60percent,basedonsourcedata.Arangeofaverageannualproductioncostsresultedformostofthesites,similartothoseinitiallyestimatedbyboththeCOEandtheAPAd.Asaresultofthisscreen,26siteswereeliminatedfromtheplanningpro-cess.ThesitesrejectedaregiveninTableC.1.Theremaining65sitesweresubjectedtoaseconditerationofscreeningwhichincludedadditionalcriteriaonenvironmentalacceptability.Thelocationofthe65remainingsitesaregiveninFigureC.1.(b)SecondIterationTheinclusionofenvironmentalcriteriaintotheplanningprocessrequiredasignificantdatasurveytoobtaininformationonthelocationofexistingandpublishedsourcesofenvironmentaldata.The27referencesourcesusedinpreparingtheevaluationmatrixincludepublicationsandmapsforwhichdatawerecollected,preparedand/oradoptedbythefollowingagencies:-UniversityofAlaska,ArcticEnvironmentalInformationandDataCenter-AlaskaDepartmentofFishandGame-AlaskaDivisionofParks-NationalParkService-BureauofLandManagement,U.S.DepartmentofInterior-U.S.GeologicalSurvey-AlaskaDistrictCorpsofEngineers-JointFederalStateLandUsePlanningCommissionC-2 Inaddition,representativesofstateandfederalagencies(includingAEIDC,ADNR,ADF&G,ADECandAlaskaPowerAdministration)wereinterviewedtoprovidesubjectiveinputtotheplanningprocess.Thebasicdatacollectedidentifiedtwolevelsofdetailofenvironmentalscreening.Thepurposeofthefirstlevelofscreeningwastoeliminatethosesiteswhichwereunquestionablyunacceptablefromanenvironmentalstandpoint.Rejectionofsitesoccurredif:(i)TheywouldcausesignificantimpactswithintheboundariesofanexistingNationalParkoraproclaimedNationalMonumentarea;(ii)Theywerelocatedonariverinwhich:-Anadromousfishareknowntoexist;-Theannualpassageoffishatthesiteexceeds50,000;-Upstreamofthesite,aconfluencewithatributaryoccursinwhichamajorspawningorfishingareaislocated.Thedefinitionoftheaboveexclusioncriteriawasmadeonlyafterareviewofthepossibleimpactsofhydropowerdevelopmentonthenaturalenviron-mentandtheeffectsoflandissuesonparticularsitedevelopment.Thefirstexclusioncriterionreflectstheexistingrestrictionstothedevelopmentofhydropowerincertainclassifiedlandareas.Informationregardingtheinterpretationsoflanduseregulationswasgatheredindis-cussionswithstateandfederalofficials,includingrepresentativesoftheFederalRegulatoryCommission(FERC)whoareresponsibleforthelicensingofhydropowerprojectsaffectingfederallands.Manylandclassificationswereidentified,suchasnationalandstateparks,forests,gamerefugeorhabitatareas,wildandscenicrivers,andwildernessareas.Additionally,thelandownershipquestioninAlaskawasfurthercomplicatedbyfederallandwithdrawals(undertheFederalLandPolicyandManagementAct)andAdministrationNationalMonumentProclamations.Afterthevariousrestrictionswereevaluated,itbecameclearthattheonlylandswherehydropowerdevelopmentisstrictlyprohibitedareNationalParksandMonuments,WildandScenicRiversandNationalWildernessAreas.Atthistime,manylandswerestillprotectedbytheNationalMonumentProclamations,pendingthepassageoftheAlaskaNationalInterestLandsBillinCongress.Otherlandclassificationsallowformonitoringandregulationofdevelopmentbythecontrollingagencyand,insomecases,vetopowerifthedevelopmentisnotconsistentwiththepurposesofthelanddesignation.NotethatnositescoincidedwitheitherWildandScenicRiversorWildernessAreas;thesewerenotincludedasexclusioncriteria.Atthetimeofevaluation,theAlaskaLandsBillhadnotyetbeenpassedbytheU.S.Congress.Thus,thedeterminationofimpactsofrestrictedlandusewasbasedontheexistinglegislation,whichincludedtheC-3 AdministrationNationalMonumentProclamationofDecember1~1978~andtheFederalLandPolicyandManagementActof1976.TheLandsBillbecamePublicLaw96-487onDecember2~1980.Theresultinglandstatuschangeshavebeenevaluatedtotheextentthattheyaffectedthechosenhydropowersites.ManysignificantsensitivitieswereidentifiedintheAlaskansetting.However~onlyoneofthesewasdeterminedtobesohighlysensitivetohydrodevelopmentandsoimportanttothestatethatitalonecouldpro-hibitthedevelopmentofasite.Thus~siteslocatedonastretchofriverusedasamajorarteryforanadromousfishpassagewereexcluded.Itwasbelievedthatthepotentialformitigationofadverseaffectsofsuchsiteswaslimited,andthatevenarelativelysmallpercentagelossoffishcouldhaveadevastatingresultforthefishery.Ofthe65sitesremainingafterthepreliminaryeconomicscreening~19siteswereunabletomeettherequirementssetforthesecondscreen.ThesesitesaregiveninTableC.l~andthereasonfortheirrejectioninTableC.2(c)ThirdIterationThereductioninthenumberofsitesto46allowedareasonablereassess-mentofthecapitalandenergyproductioncostsforeachoftheremainingsitestobemade.AdjustmentsweremadetotakeintoaccounttransmissionlinecostsnecessarytolinkeachsitetotheproposedAnchorage-Fairbanksintertie.Thisiterationresultedintherejectionof18sitesbasedonjudgementaleliminationofthemoreobviousuneconomicorlessenvironmentallyacceptablesites.Theremaining28sitesweresubjectedtoafourthiterationwhichentailedamoredetailednumericalenvironmentalassessment.The18sitesrejectedinthethirditerationaregiveninTableC.1.(d)FourthIterationTofacilitateanalysis~thesiteswerecategorizedintosizesasfollows:-Lessthan25MW:5sites;25MWto100MW:15sites-Greaterthan100MW:8sites.Thefourthandfinalscreenwasperformedusingdetailednumericalenviron-mentalassessmentwhichconsideredeightcriteriachosentorepresentthesensitivityofthenaturalandhumanenvironmentsateachofthesites.Threemainaspectswereincorporatedintotheselectionofthesecriteria:-Criteriamustrepresenttheimportantcomponentsoftheenvironmentalsettingthatmaybeimpactedbythedevelopmentofahydroelectricpro-ject.-Criteriamustincludecomponentsthatrepresentexistingandpotentiallanduseandmanagementplans.C-4 -Informationrelatingtothesecriteriamustbereasonablyavailableandeasilyincorporatedintoascreening/evaluationprocess.TheeightevaluationcriteriaarelistedinTableC.3.Eachcriterionwasdefinedtoidentifytheobjectivesusedforinvestigatingthatcriterion.Followingtheselectionoftheevaluationcriteria,itwasnecessarytodefinethesignificanceofavarietyoffactorswithineachsetofcriter-ia.Underthecategoryofanadromousfisheries,forexample,itisneces-sarytodifferentiatebetweenasitewhichwouldadverselyaffectamajorspawningareaandasitewhichisusedonlyforpassagebyarelativelysmallnumberoffish.Foreachoftheevaluationcriteria,therefore,asystemofsensitivityscalingwasusedtoratetherelativesensitivityofeachsite.Aletter(A,B,CorD)wasassignedtoeachsiteforeachoftheeightcriteriatorepresentthissensitivity.ThescaleratingsystemisdefinedinTableC.4.EachevaluationcriterionhasadefinitivesignificancetotheAlaskanenvironmentanddegreeofsensitivitytoimpact.Adiscussionofeachcriterionisappropriatetodeterminetheimportanceofthatcriterioninthecontinuedstudyorrejectionofthehydroelectricsites.(i)BigGameThepresenceofbiggameisespeciallysignificantintheAlaskanenvironment.Specialprotectionandmanagementtechniquesareem-ployedtoensurepropagationofthespeciesandcontinuedabundanceforsubsistanceandcommercialharvestingaswellasrecreationuses.Thiscriterionhasaveryhighimportanceinthelifestyleandeco-nomicwellbeingoftheAlaskanpeople.Sitespecificinformationwasextractedfromaseriesofmapoverlayswhichidentifiedtypesofbiggamehabitatswithvaryingimportancetosurvivalofthespeciesconsidered.Forexample,amapmayhavealargeareadesignatedas"moosepresent"or"moosedistribution".Withinthatlargedistributionarea,smallerareaswereidentifiedasseasonalconcentrationareasorcalvingareas.Thesesmallerareaswereconsideredtobemoresensitivetodevelopmentthanthe largeareasbecausetheysatisfyspecificneedswithinthelifecycleofthemoose,andbecausetheavailabilityofappropriatelandislimited.Ofthereferencesinspected,"Alaska1sWildlifeAtlas,VolI"wasregardedasthemostauthoritativesource,andtookprecedenceinthecaseofconflictinginformation.References"MuskOxenandCaribou"and"LargeMammals"generallyaddedtothebodyofknowledge.Refer-ences"BearDenningandGoatRange,"DallSheep,DeerandMooseCon-centrations"and"DistributionofCaribouHerdsinAlaska"werereviewed,buthadlittleinputwhichcorrespondedwiththesitessurveyed.C-5 (ii)ArgiculturalPotentialAgriculturalpotentialwasassignedarelativelyhighimportance.Thisisbecauseitisanindicatonofthepotentialfortheselfsuffi-ciencyofanyarea,andtheavenuestowardsselfsufficiencyrequirespecialconsiderationintheeconomicclimateofAlaska.ThebestagriculturalresourcesidentifiedintheRailbeltregionarelocatedinthelowlandsadjacenttothelowerSusitnabasin.TheseincludetheYentna/SkwentnasystemandthenorthernandeasternshoresofCookInletaswellastheTananaandNenanaRivervalleysandtheupperpartoftheCopperRiverbasin.Thelatterwasidentifiedasclimaticallymarginal.Theamountoflandidentifiedwithsuitablefarmingsoilsisrela-tivelysmallandwasassignedahighersensitivitythanlandwithmarginalfarmingsoils.Landswithnosuitablesoilsidentifiedwereassignedthelowestsensitivity.MapreferenceIICultivatableSoilslland"AlaskaResourcesInventory,AgriculturalandRangeResources"wereusedtoidentifylandswithagriculturalpotentialintheRailbelt.(iii)Waterfowl,RaptorsandEndangeredSpeciesTheRailbeltprovidesextensivehabitatsformanyspeciesofwaterfowlaswellashabitatsforsomethreatenedandendangeredbirdspecies.Theprotectionofthesehabitatsinthefaceofdevelopmentisacon-cernofmanyenvironmentalistsandecologists.Asanevaluationcri-terion,thiswasconsideredtobeslightlylessimportantthanthebiggameorfisheriescriteriabecauseofthecombinedecologicalandeconomicimportanceofthosetwocriteria.Inevaluatingthesensitivityofthevariousfactorsprovidinginputtothesecriteria,threereferencemapsweresurveyed:"Alaska'sWildlifeAtlasVolII"providedinformationregardingwaterfowlandseabirds;IIMigratoryBirds:Seabirds,Raptors&EndangeredSpecies"hadinformationregardingseabirdsandraptorhabitats;andIIBirdsllidentifiedendangeredandthreatenedspecieshabitats.Generally,raptorandendangeredspecies'habitatswereconsideredmostsensitive.Highdensityandkeywaterfowlareaswereconsideredtobemoderatelysensitive.(iv)AnadromousFisheriesTheanadromousfisheriesresourceisanessentialcomponentofAlaska'seconomyandlifestyleaswellasitsnaturalenvironment.Itisthesingleresourcemostaffectedbyhydropowerdevelopmentduetothenatureofthedevelopmentitselfwhichnotonlyhampersthepassageoffishbutmayalsoalterflowconditionsessentialtotheanadromouslifecycle.Becauseofitssensitivitytohydropowerdevelopment,theanadromousfisheriesresourcewasveryhighlyconsideredinthisevaluation.C-6 Thecomparativesensitivityofthesiteswasbasedonthenumberofspeciesidentifiedaspresentorspawninginthevicinity.Particularemphasiswasplacedontheriverupstreamofproposeddamsitesand,wheninformationwasavailable,ontheestimatednumberoffishiden-tifiedpassingcertainpoints.Somesiteswereexcludedinprelimin-aryscreeningbecausetheywereidentifiedasmajorlocationsforfishpassage(greaterthan50,000annually.)Themostsensitiveoftheremainingsiteswerethosewiththelargestnumberofspeciespresentandwiththemostextensivespawningareasupsteamofthedamsite.Lowestsensitivitycorrespondedwiththeabsenceofanadromousfishinthearea.Severalcompiledreferenceswereavailablefordeterminingtheextentoffisheries'presenceateachofthehydrositesconsidered.Themostcomprehensivereferencewas"AlaskaFisheriesAtlas"VolumeI,whichindicatedonUSGStopographicalmapsthepresenceofeachoffivespeciesofsalmonandtheirspawningareasforallareasofinterest.Twomapoverlayswereusedtodeterminemoregenerallythepresenceofanadromousfisheries:"Fisheries"and"MarineMammalsandFish".ThisinformationwasalsocheckedagainsttheCh2M-Hillreport"ReviewofSouthCentralAlaskaHydropowerPotential"forsomeofthesites.(v)WildernessConsiderationNationalandstateinterestinthepreservationofnaturalaestheticqualitiesinAlaskacontinuetobetheimpetusforstudiesandlanduselegislation.Substantialamountsoflandhavebeenidentifiedandprotectedunderstateandfederallaw.However,otherlandshavebeenidentifiedfortheiruniquewilderness,scenic,naturalandprimitivequalitiesbuthavereceivednoparticularprotection.Thisfactorwasconsideredtotheextentthatanyofthepotentialhydrositeswouldimpacttheaestheticqualityoftheseunprotectedlands.TwomapoverlayspreparedbytheJointFederalStateLandUsePlanningCommissionwereused:"SelectedPrimitiveAreasinAlaskaforConsid-erationforWildernessDesignation"and"Scenic,NaturalandPrimitiveValues".(vi)Cultural,RecreationandScientificfeaturesThesecriteriareflecttheimportanceplacedonthehistorical,cul-turalandrecreationalvaluesofcertainlandmarks,aswellasthevaluesofscientificresourcesatidentifiedlocations.Areasofvaryingsignificancewereidentifiedbythereferencesourcesandcom-parativesensitivitieswereassignedaccordinglyifpotentialhydrositescorrespondedwithidentifiedareas.Threemapoverlayswereusedtosubstantiatethesecriteria:"Recrea-tion,CulturalandScientificFeatures","NationallySignificantCul-turalFeatures",and"ProposedEcologicalReserveSystemforAlaska".C-7 (vii)RestrictedLandUseAsignificantamountoflandinAlaskaisclassifiedasnationalorstateparks,wildlifeareas,monuments,etc.Theseclassificationsaffordvaryinglevelsofprotectionfromcompleteexclusionofanydevelopmentactivitytoamonitoringorregulationofdevelopmentoccurringontheprotectedlands.Usingthiscriterionasanindica-tionofthelegalrestrictionsthatmighthindertheimplementationofahydroelectricdevelopment,thecomparativesensitivitiesweredefined.Ifapotentialhydrositewaslocatedwithinanationalparkormonument,thesitewasexcludedduringpreliminaryscreeningfromfurtherconsideration.Otherlandclassificationswerelesssevere.Thiscriterion,althoughitmaybemoreofanindicationofinstitutionalfactorsthantheactualsensitivityofthesitearea,representsrealissuesthatwouldaffectdevelopment.Landstatuswasidentifiedusingmapsandreferencematerialspreparedbystatesources:IIGenera1izedStateLandActivityll,IIGameRefuges,CriticalHabitatAreasandSanctuariesll,andfederalsources,USGSAlaskaMapEandQuadrangleMaps,IIAdministrationNationalMonumentProclamationandFLDMAWithdrawalsll,IIAlaskaIllustratedLandStatusll.ItshouldbenotedthatthisevaluationwasperformedbeforethepassingoftheAlaskaNationalInterestLandsConservationAct(PL96-487).Theresultsoftheapplicationofthiscriterionweresubsequentlycomparedagainstthemandatesofthisfederalact.Nosubstantialeffectsonthescreeningresultswerefound.(viii)AccessThemainpurposeofthiscriterionwastoindicatehowthepotentialhydrositesfitintotheexistinginfrastructure.Inotherwords,theconcernwastoidentifythoseareaswhichwouldbemostandleastaffectedorchangedbytheintroductionofroads,transmissionlinesandotherfacilities.Thehighestsensitivitywasassignedtothesiteswhichwerethefarthestfromtheexistinginfrastructure,indicatingareaswiththegreatestpotentialforimpacts.Lowersensitivitieswereassignedtoareaswhereroads,transmissionlinesandsettlementsalreadyexist.Althoughthiswasanimportantcriteriontoconsider,itwasnotgivenahighweightingwhencomparedtoothercriteriaduetothesubjectivenatureoftheinterpretationsmade.Itcouldbe,forexample,thatanexistingsmallsettlementwouldbemoreadamantlyopposedtodevelop-mentinanareawherenobodyhaspresentlysettled.InformationwasgarneredfromnotesinIIReviewoftheSouthcentralHydropowerPotentialllandroadmapsofthearea.(ix)SummaryofCriteriaWeightingThefirstfourcriteria-biggame,agriculturalpotential,birdsandanadromousfisheries,werechosentorepresentthemostsignificantfeaturesofthenaturalenvironment.TheseresourcesrequireC-8 protectionandcarefulmanagementduetotheirpositionintheAlaskanenvironment,theirrolesintheexistingpatternsoflifeofthestateresidentsandtheirimportanceinthefuturegrowthandeconomicinde-pendenceofthestate.Thesefourcriteriawereviewedasmoreimpor-tantthanthefollowingfourcriteriaduetotheirquantifiableandsignificantpositioninthelivesoftheAlaskanpeople.Theremainingfourcriteria-wilderness,cultural,recreationandscientificfeatures,restrictedlanduse,andaccesswerechosentorepresenttheinstitutionalfactorstobeconsideredindetermininganyfuturelanduse.Thesearespecialfeatureswhichhavebeeniden-tifiedorprotectedbygovernmentallawsorprogramsandmayhavevaryingdegreesofprotectedstatus,orthecriteriarepresentexist-inglandstatuswhichmaybesubjecttochangebythepotentialdevel-opments.Itmustbenotedthattheinterpretationsplacedonthesecriteriaaresubjective,althoughcarewastakentoensurethatthemanyviewpointswhichmakeupAlaska'ssociopoliticalclimatewererepresentedintheevaluation.Thelatterfourcriteriawereconsideredlessimportantinthecomparativeweightingofcriteriamainlybecauseofthesubjec-tivenatureandlowerdegreeofreliabilityofthefactscollected.Datarelatingtoeachofthesecriteriawerecompliedseparatelyandrecordedforeachsite,formingadata-basematrix.Then,basedonthesedata,asystemofsensitivityscalingwasdevelopedtorepresenttherelativesensitivityofeachenvironmentalresource(bycriterion)ateachsite.Thescaleratingsusedaresummarizedbelow.AdetailedexplanationofthescaleratingmaybefoundinTableC.5.A -Exclusion(usedforsitesexcludedinpreliminaryscreening)B -HighSensitivityC-ModerateSensitivityD -LowSensitivityThescaleratingsforthecriteriaateachsitewererecordedintheevaluationmatrix.Siteevaluationsofthe28sitesunderconsidera-tionaregiveninTableC.6.Preliminarydataregardingtechnicalfactorswerealsorecordedforeachpotentialdevelopment.Parametersincludedinstalledcapacity,developmenttype(damordiversion),damheight,andnewlandfloodedbyimpoundment.ThecompleteevaluationmatrixmaybefoundinTableC.7.Inthismanner,theenvironmentaldatawerereducedtoaform fromwhicharelativecomparisonofsitescouldbemade.Thecomparisonwascarriedoutbymeansofarankingprocess.C-9 (x)RankWeightingandScoringForthepurposeofevaluatingtheenvironmentalcriteria,thefollow-ingrelativeweightswereassignedtothecriteria.Ahighervalue·indicatesgreaterimportanceorsensitivitythanalowervalue.BigGame8AgriculturalPotential7Birds8AnadromousFisheries10WildernessValues4CulturalValues4LandUse5Access4Thecriteriaweightsforthefirstfourcriteriawerethenadjusteddown,dependingonrelatedtechnicalfactorsofthedevelopmentscheme.Damheightwasassumedtobethefactorhavingthegreatestimpactonanadromousfisheries.Allthesiteswererankedintermsoftheirdamheightsasfollows:-Height~150I:Rank+-Height1501-3501:Rank++-Height>3501:Rank+++Adamwiththelowestheightranking(+)wouldhaveleastimpact,andwouldthereforeresultinthefisheriesweighttobeadjusteddownbytwopoints.Similarly,adamofheight(++)wasadjusteddownbyonepoint.Adamofheight(+++)wouldhavethegreatestimpactandtheweightremainedatitsdesignatedvalue.Theamountofnewlandfloodedbycreationofareservoirwascon-sideredtobetheonefactorwithgreatestimpactonagriculture,birdhabitat,andbiggamehabitat.Siteswererankedintermsoftheirnewreservoirareaasfollows:-Area<5000acres:Rank+-Area5000-100,000acres:Rank++-Area~100,000acres:Rank+++Thesameadjustmentsweremadeforthebiggame,agriculturalpoten-tials,andbirdhabitatweightsbasedonthisfloodedareaimpact(seeTableC.8).Notethatfordevelopmentswhichutilizedanexistinglakeforstorage,thenewareafloodedwasassumedtobeminimal(+).C-10 Thescaleindicatorswerealsogivenaweightedvalueasfollows:- B=5C=30=1Tocomputetherankingscore,thescaleweightsweremultipliedbytheadjustedcriteriaweightsforeachcriteriaandtheresultingproductswereadded.Twoscoreswerethencomputed.Thetotalscoreisthesumofalleightcriteria.Thepartialscoreisthesumofthefirstfourcri-teriaonly,whichgivesanindicationoftherelativeimportanceoftheexistingnaturalresourcesincomparisontothetotalscore.(xi)EvaluationTheevaluationofsitestookplaceinthefollowingmanner:siteswerefirstdividedintothreegroupsintermsoftheircapacity.Basedontheeconomics,thebestsiteswerechosenforenvironmentalevaluation.TableC.10liststhenumberofsitesevaluatedineachofthecapacitygroups.Thesiteswerethenevaluatedasdescribedabove.Theywerelistedinascendingorderaccordingtotheirtotalscoresforeachofthegroups.Thepartialscorewasalsocompared.Thesiteswerethengroupedasbetter,acceptable,questionable,orunacceptable,basedonthescores.Thesamegeneralstandards(e.g,cut-offpoints)wereusedforallgroups.(xii)AnalysisThepartialandtotalscoresforeachofthesites,groupedaccordingtocapacity,aregiveninTableC.10.- a -25MWOfthefivesitesevaluated,allfiveweredeterminedtobeaccep-table,basedontheoverallstandards.ThreeofthesesiteswerejUdgedasagrouptobebetterthantheothertwowhichhadhigherpartialandtotalscores.-25-100MWAcutoffpointofapproximately134forthetotalscoreandapproxi-mately100forthepartialscorewasused.Sitesscoringhigherwereeliminated.Thesevensitesscoringlowerwerere-examined.ThreedevelopmentsatBruskasna,BradleyLake,andSnowwerethebestsitesidentified.C-11 Oftheremainingfour,CoffeeandSeetnawereidentifiedasques-tionablebecauseofanticipatedsalmonfisheriesproblems.LoweandCachescoredonlyslightlybetter,butLowehasminimalfisheriesproblems,andtheCachesiteisfarthestupstreamontheTalkeetnaRiver,beyondwhichthesalmonmigrateonlyaboutfivemiles.->100MWAgain,thesamecutoffpointforacceptablesiteswithtotalscoresof134andpartialscoresof100used.Thesitesfelleasilyintothetwogroupingsofacceptableandunacceptable.(xiii)ResultsSixteensiteswerechosenforfurtherconsideration.Threecon-straintswereusedtoidentifythese16sites.First,themosteco-nomicalsiteswhichhadpassedtheenvironmentalscreeningwerechosen.Secondly,siteswithaverygoodenvironmentalimpactratingwhichhadpassedtheeconomicscreeningwerechosen.Andfinally,arepresentativenumberofsitesineachcapacitygroupweretobechosen,TableC.10.Fromthelistof16sites,10wereselectedfordetaileddevelopmentandcostestimatesrequiredasinputtothegenerationplanning.ThetensiteschosenareunderlinedinTableC.l.Threesites,StrandlineLake,Hicks,andBrownewereidentifiedbytheCh2M-HillReporttoCaEasbeingenvironmentallyverygood.Thesesiteswereincluded,eventhoughtheirassociatedeconomicswerenotasgoodasmanyoftheothersiteswhichhadalsopassedtheeconomicscreening.TheChakachamnasitehadbothaveryhigheconomicrankingandagoodenvironmentalratingintermsofthesensitivityofitsnaturalresourcestodevelopment.ChakachamnawasalsoidentifiedbytheCh2M-Hi11reportashavingminimalenvironmentalimpacts.ItshouldbenotedthatundertherecentlypassedAlaskaNationalInterestLandsConservationAct(PL96-487,December2,1980)thelandsincludingtheChakachamnasitehavenotreceivedprotectedstatusofanytype.ThisappliestoboththeprojectareaandtheexistingLakeChakachamna.Althoughtheboundaryofdesignatedwildernessareaislocatedafewmilesfromtheeasternendofthelake,operationofthelakewouldhavelittledirecteffectonthewildernessarea.BecausetheChakachamnasiteisdesirableinotherrespects,itisbeingconsid-eredasaviablealternatecompetingwiththeSusitnaProject.ThreesiteswerechosenonthelkeetnaRiver.TheseareCache,Keetna,andTalkeetna-2whicharebeingstudiedasanintegratedsystemalternative.Althoughtheidentifiedenvironmentalproblemsaresignificant,thesystemisbeingstudiedforseveralreasons.ItC-12 isbelievedthatwiththesystemapproach,theincrementalimpactsofbuildingasecondorthirdplantonthesameriversystemwouldbesmallerthantheimpactsassociatedwithbuildingplantsoncompletelyseparaterivers.Theintegratedsystemnotonlyimprovestheeconomicpotentialoftheoperatingcapacity,butalsoallowsforbettercon-troloverregulationofstreamflowsasneededbythedownstreameco-systems.Secondly,thechoiceoftheTalkeetnaRiverwasmadeoverotherriverswithpotentialfordevelopmentofsimilarsystems,becausetheenvironmentalsensitivityoftheTalkeetnawasnotasgreatasthatoftheYentna-Skwentnabasin,theChulitnaRiverorthelowerSusitnabasin,particularlywithregardstothepresenceofan-adromousfishorbiggame.Andfinally,theTalkeetnaRiverdevelop-mentsweresomeofthebestsiteseconomically,thusprovidingbettercompetitiontoSusitna.Theremainingsitesofthe10studiedindetailareAllisonCreek,Snow,andBruskasna.Thesearesitesthatwereidentifiedbytheenvironmentalevaluationasbeingthebestenvironmentallyofthe28economicallysuperiorsites.(e)PlanFormulationandEvaluationSteps4and5intheplanningprocessaretheformulationofthepreferredsitesidentifiedinStep3intoRailbeltgenerationscenarios.Toade-quatelyformulatethesescenarios,theengineering,energyandenviron-mentalaspectsofthe tenshortlistedsiteswerefurtherrefined(Step4).Engineeringsketchlayouts(FiguresC.2toC.lO)wereproducedforsevenofthesiteswithcapacitiesof50MWorgreater,andsitespecificconstruc-tioncostestimateswerepreparedonthebasisofthismoredetailedinfor-mation(TablesC.12throughC.18).Forthethreeremainingsites,con-structioncostsweredevelopedbyaprocessofjudgementalinterpolationonthebasisoftheestimatesforthesevenlargerdevelopments.CostsandparametersassociatedwithalltensitesaresummarizedinTableC.19.Thesecostsincorporatea20percentallowanceforcontingenciesand10percentforengineeringandowner'sadministration.Costofmoneyhasagainbeenassumedtobethreepercent,netofinflation.Energyandpowercapabilitywasdeterminedforeachofthesitesusingamonthlystreamflowsimulationprogram(AppendixF).TheannualaverageenergyforeachofthethesitesarealsogiveninTableC.19.Installedcapacitiesweregeneral-lyassumedthatwouldyieldaplantfactorforthedevelopmentsofapprox-imately50percent.ThisensuresgeneralconsistencywithSusitnadevelop-mentsandRailbeltsystemrequirements.TheformulationofthetensitesintodevelopmentplansresultedintheidentificationoffiveplansincorporatingvariouscombinationsofthesesitesasinputtotheStep5evaluations.ThefivedevelopmentplansaregiveninTableC.20.TheessentialobjectiveofStep5wasestablishedasthederivationoftheoptimumplanforthefutureRailbeltgenerationincorporatingnon-Susitnahydrogenerationaswellasrequiredthermalgeneration.ThemethodologyusedintheevaluationofalternativegenerationscenariosfortheRailbeltarediscussedindetailinSection8.ThecriteriononwhichthepreferredplanwasfinallyselectedintheseactivitieswasleastpresentworthcostbasedoneconomicparametersestablishedinSection8. Theselectedpotentialnon-Susitnahydrodevelopments(TableC.19)wererankedintermsoftheireconomiccostofenergy.Chakachamnaisthehigh-estranked(preferred)withacostofenergyof40$/1000kWhandHicksisthelowestrankedwithacostofenergyof1612$/1000kWh.Thepotentialdevelopmentswerethenintroducedintotheall-thermalgeneratingscenarioingroupsoftwoorthree.Themosteconomicschemeswereintroducedfirstfollowedbythelesseconomicschemes.TheresultsoftheserunsaregiveninTableC.21andillustratethataminimumtotalsystemcostof$7040millioncanbeachievedbytheintroduc-tionoftheChakachamna,KeetnaandSnowprojects(PlanC.2).Thisplanincludes1211MWofthermalcapacityandassumesamediumloadforecast.Norenewalofgasplantsatretirementisalsoassumed.Themake-upoftheRailbeltgenerationsystemunderthisleastcostscenarioisshowninFigureC.ll.AdditionalsitessuchasSnow,StrandlineandAllisonCreekcouldbeintroducedwithoutsignificantlychangingtheeconomicsofthegenerationscenarios.Theintroductionoftheselatterprojectswouldbebeneficialintermsofdisplacingnon-renewableenergyresourceconsumption.C-14 LISTOFREFERENCES(1)U.S.ArmYCorpsofEngineers,NationalHydropowerStud~,July,1979.(2)AlaskaPowerAdministration,HydroelectricAlternativesfortheAlaskaRailbelt,February,1980.(3)Handy-Whitman,CostIndexforHydropowerProductioninthePacificNorthwest,1978.C-15 TABLE C.1 -SUMMARY OF RESULTS OF SCREENING PROCESS ElImInatIon tllmlnatlOn thminabon thmInatlOn Iteration Iteration Iteration Iteration 1 1 1 1 Site 1 2 3 4 Site 1 2 3 4 Site 1 2 3 4 Site 1 2 3 4 Allison Creek Fox *Lowe *Talachulitna River *Beluga Lower *Gakona *Lower Chulitiua *Talkeetnna R.-Sheep * Beluga Upper *Gerstle *Lucy *Talkeetna - 2 Big Delta *Granite Gorge *McClure Bay *Tanana RIver *Bradley Lake *Grant Lake *McKinley River *Tazlina *Bremmer R.-Salmon *Greenstone *McLaren River *Tebay Lake *Bremmer R.-S.F.*Gulkana River *Million Dollar *Teklanika *Browne Hanagita *Moose Horn *Tiekel River *Bruskasna Healy *Nellie Juan River *Tokichitna *Cache Hicks Nellie Juan R.-Upper *Tat atlanika *Canyon Creek *'JiiCJ<River *Ohio *Tustumena *Caribou Creek *Johnson *Power Creek *Vachon Island *Carlo *Junction Island *Power Creek - 1 *Whiskers *Cathedral Bluffs *Kanhshna River *Ramport *Wood Canyon *Chakachamna Kasilof River *Sanford *Yaned - 2 *Chulitna E.F.*Keetna Sheep Creek *Yentna *Chulitna Hurrican *~ake *Sheep Creek - 1 *Chulitna W.F.*Kenai Lower *Silver Lake *Cleave *Killey River *Skwentna *Coal *King Mtn *Snow Coffee *Klutina *"SOlOmon Gulch *Crescent Lake *Kotsina *Stelters Ranch *Crescent Lake - 2 *Lake Creek Lower *Strandline Lake Deadman Creek *Lake Creek Upper *Summit Lake *Eagle River *Lane *Talachulitna * -- NOTES: (1)Final site selection underlined. *Site eliminated from further consideration. SiteHealyCarloYanert- 2CleaveTebayLakeHanagitaGakonaSanfordTABLEC.2-SITESELIMINATEDINSECONDITERATIONCriterionNationalPark(Mt.McKinley)NationalMonument(Wrangell-St.EliasNationalPark)andMajorFisheryNationalMonument(Wrangell-St.EliasNationalPark)LakeCreekUpperMcKinleyRiverTeklanikaCrescentLakeKasilofRiverMillionDollarRampartVachonIslandJunctionIslandPowerCreekNaionalMonument(DenaliNaitonalPark)NationalMonument(LakeClarkNationalPark)MajorFishery EvaluatIonCriterIaTABLEC.3-EVALUATIONCRITERIAGeneralConcerns(1)BigGame(2)AgriculturalPotential(3)Waterfowl,raptors&endangeredspecies(4)Anadromousfisheries(5)WildernessConsideration(6)Cultural,recreation&scientificfeatures(7)Restrictedlanduse(8)Access-protectionofwildliferesources-protectionofexistingandpotentialagriculturalresources-protectionofwildliferesources-protectionoffisheriesprotectionofwildernessanduniquefeatures-protectionofexistingandidentifiedpotentialfeatures-considerationoflegalrestrictiontolanduse-identificationofareaswherethegreatestchangewouldoccur ScaleRatingA.EXCLUSIONB.HIGHSENSITIVITYC.MODERATESENSITIVITYD.LOWSENSITIVITYTABLEC.4-SENSITIVITYSCALINGDefinitionThesignificanceofonefactorisgreatenoughtoexcludeasitefromfurtherconsideration.Thereislittleornopossibilityformitigationofextremeadverseimpactsordevelopmentofthesiteislegallyprohibited.1)Themostsensitivecomponentsoftheenvironmentalcriteriawouldbedisturbedbydevelopment,or2)Thereexistsahighpotentialforfutureconflictwhichshouldbeinvestigatedinamoredetailedassessment.Areasofconcernwerelessimportantthanthosein"B"above.1)Areasofconcernsarecommonformostormanyofthesites.2)Concernsarelessimportantthanthoseof"C"above.3)Theavailableinformationaloneisnotenoughtoindicateagreatersignificance. TABLE C.5 -SENSITIVITY SCALING OF EVALUATION CRITERIA r-v-l;ilu-aHon--c-fiter fa ----~---------SCALE ABC D Exclusion High Moderate Low Big Game: Agricultural Potential Waterfowl,Raptors and Endangered Species Anadromous Fisheries Wilderness Consideration Cultural,Recreational and Scientific Features -major anadromous fish corridor for three or more species -more than 50,000 salmon passing site -seasonal concentration are key range areas -calving areas upland or lowland soils suitable for farming -nesting areas for: •Peregrine Falcon •Canada Geese •Trumputee Swan -year round habitat for Neritic seabirds and raptors -key migration area three or more species present or spawning identified as a major anadromous fish area All of the following -good to high quality: •scenic area •natural features •primitive values -selected for wilderness consideration -existing or proposed historic landmark -reserve proposed for the Ecological Reserve System -big game present -bear denning area -marginal farming soils -high density waterfowl area -waterfowl migration and hunt ing area -waterfowl migration route -waterfowl nesting or or molt area less than three species present or spawning -identified as an impor- tant fish area Two of the following -good to high quality: •scenic area •natural features •primitive value -site in or close to an area selected for wilderness consideration -Site affects one or more of the following: boating potential recreational potential historic feature historic trail archeological site ecological reserve nomination cultural feature -habitat or distribu- t ion area for bear no identified agri- cultural potential -medium or low density waterfowl areas -waterfowl present not identified as a spawning or rearing area. One or less of the following good to high quality: •scenic area •natural features primitive value -site near one of the factors in B or C TABLE C.5 (Continued) I:valuaHon-Criteria SCALEA-----B C ~U Exclusion High Moderate Low Restricted Land Use Restricted Land Use -Significant impact to: •Existing National Park Federal Lands with- drawn by National Monument Proclaima- tions -Impact to: •National Wildlife Range State Park •State game refuge, range,or wilderness preservation area -no existing roads, railroads or airports -terrain rough and access difficult -increase access to wilderness area -Increase: •Nat ional Forest •Proposed wild and scenic river •Nat ional resource area •Forest land withdrawn for mineral entry -existing trails -proposed roads or -existing airports -close to existing roads -In one of the following: •State land Native land •None of A,B,C -existing roads or railroads -existing power lines fABLE C.6 -SITE EVAlUATIONS Site EYilUBlIon CrU"i'lii Agr (cultural Wit.errowl'·Raplors,AnilCffOiiOOe "lJoeroeis Ciill,ijral,··RiJereitrOiliI;ffMtflctecJ Big G....Polentiel Endengered SpecIee risherlee Consideration end Scientific risherIee lend Use Allison Creek -Bleck end Grizzly beer -None lde·,U ned present Oredley loke -Block end Grizzly beer -2~10 JO percenl ef presnt soil mergIne11 sull- -Hoose presont.able for fermlng -high QUelity foreete Browne -Bleck end Gr Iz zly beor -ttJre than SO percent _~~:n~resenl mergInslly suitable ror forming -Caribou wintor range Bruskosno -Bleck end Grizzly beor -None ldentined prescnt -Hoose present -Caribour wint.er fange O1nkochomno -mock beer hohllol -tlplnnd opruce,herd- -Hoose present wood foreot -Veer reund hab Iisl for neritic seAblrdo lind replors -Peregr lne relcon nest lng eres -Wolsrrowl presenl -Peregrine ralcon nest lng Bre08 -low density or ...ier- rowl -low denolly or weler- rowl -Nooting en<!molt Ing area -Waterfowl neet log nnd molt log area -Spewnlng erea ror 2 BaIntOn species -None ldenti fiod -None -None -Two spec leo present -High io good guallty 8Ct!nlc .f88 -Good 10 high QUelliy BCffnery -None -Good 10 high quoilly Bcenery -Area under wilderness consldeat ion t -Good 10 high guaHI y scenery -Primitive end nalural rellt.ureo -None Identified -008!Inq area -Boailng potential -Boating polential -Proposed ecological reoerve site -Roollng oreos -Noar Chugach Nationol fore.I -None ldentl fied -None ldenl Ifled -None ldenU ned -None IdlmU ned Coffee Cethedrel B1ufr. Hicks Johnson Keelno Kenai lake -Black end Grizzly beor present -!-bone present -Alack end Grizzly bear present -f.bose present -De 11 sheep preseni -Moose concentration area -Aleck and Grizzly baer present -Car lbou praaani -Hoose wintering aren -Bleck end Grizzly beor preeent -t-boae,car tbou and bison present. -Black ...d Grizzly beer preeeni -Car tbou winter are. -Hoose rall/wlnler coneentrotlon ares -Bleck ..d Grizzly bear -I:~:~ep habital -Hooaa fall/wlnler concentration area -Hore Ihan ~O%of upper lands suilable fer egr I.ultursl -Good forests -Hore Ihen ~O%or lend msrglnol ror rsrlOing -Upland spruce-herdwnod rareet -None ldenlifled -25 10 ~or uplen<! soil 8uitoble ror farming -Uplend spruce-hardwood forest -None ldenllfled -None Identified -Coaelal helOleck- alUcD sprue.foreat -Key wslerfowl hobital -low density of waler- rowl -Noating en<!oooiting Bren -lIalerrowl noollng ond 1fM)1t lng area -low dens ily walerfowl Ireo -Noating end molt Ing area -None ldenti ned -Wetarrowl neollng end ooolting ares -Four species present, two tlpownlng in oren -One spec les present -rar downotreem of aite only -Salmon epuwnlng arOIl, one speciee preoent -four spec le8 present, one opecies spawning near site -rour epee lea present, twot9Pawnlng -None ldenli ned -Good scenery -None ldenli ned -None ldenli ned -Coed 10 high QUal Uy pr 1..llive lando ::tur~·~~;ru~;:nory -Booling area -None ldenli fled -None ldenli fled -Boating polenlial -High booting polentlal -Bosting polential -None ldenU ned -None ldenlHled -No precenl restrlct loon -None ldenll fled -None ldenll ned -Chugech Nalionsl rorest TABlE C.6 (Continued) srre-E:ViiluoHOi1 CfitcH" ~11ufaT --WarerrowI,·Rij)tiro,lVln:oro..ons -lfllOiroos9 ~~l:Ul{ur~8tlonolf--~ _______-'B"'I"'9L.e-==-_Potential Endangered Specla.Fisheriaa Conaideratlon end Scientific Fioharie.tend lIae Klutln.-Black end Grizzly be.r -25 to SO percent of -tow donally watarfowl -Two epecles present,-HIt.:quality acanery -lIo.t Ing potent 1.1 -Ilona ldontlfod pre88nt .011a ...rglno1 for orea one spec leo spawn in -Ha urol For...tlone -Car Ibou preaent forming -Nesting and 11I011 Ing vicinity of .lIa -Prlmll Ive lend. -t-boso f8l1 concentro--Climate marglnel for 8r08 -Selected for wllder- t ion area far..lng upland spruce-MSS COf1s1derot Ion hardwood fora.t t.ne -Black bear praoent -""re than SO percont -low density waterfowl -five specles prosent -None ldenl iflod -'::~:';1I:::rortunlt lee -Nona ldenll find -Hoose present .of the .0110 In upper-oroe and 8PSwn 1n uUe -Caribou proscnt lend••ultobl.for -Ne.tlng and tROlting vicinity rer..lng orca -IIottomlend spruco- poplar foreot lowe -Rlock and Grizzly boor -IIono ldentl fled -Per Igrona falcon -One opec lea present,-Good to high qu.llly -Hlotoricol feature -located neSf the present -Co ••tal we.tarn hntRlock-nt'!st log eroa others downstream of scenery -Propos.ed ecologlco1 border of Olugoch -MJosc present s ltka spruce forcst aile -Area se lected for rOBffrvo stte Net looel roroot wlldernees consideration tower Oluillna -Black end GrizZly b••r -""re th.n SO parcont of -Nedlum denolty ...terfowl -fOUf opectes present f -Area selected for -Boot Ing potent 1.1 -None I,font I flod present tho upland eoU.oull-area throe opown Ing In wilderness considerot ton -Caribou present able for farming -~otlng .nd mol t Ing vicinity areD -Bleck and Gr Izzly boor -~ne ldent Iflod -Veor round hablt.t ror present -Coeotal ....torn hemlock-neritic ...oblrdo end -High deneity of 80.10 a1th opruce foreat reptora Silver loke Skwentna -Olock end Grizzly b••r present -Moose wtnter conesot fo- tion orea -SO percent of upparlande -low donolty ...terfowl suitable for forming area -lowland epruce --Neet Ing and molting hardwood rorool orca -One specloa preeont, more downst reM -Three apeeies prt'uh,nt, $powning in eres -Coed to high quollty eeeoery •Primitive volue -None identified -Bo.t Ing areo potont 101 =~:~~~Yc:~o:rollo -Olugocl1 Not lonol fore" -None ldentl fled Snow -Bl.ck bear present -Hene ldentl fled -0011 ohaep hablt.to -""088 winter concentra- tion oreB -Neotlng Ond molting BreD -Hene -!lone ldantl fled -Proposed ecologtcot rem!lrve site -locotod In OlUQoch Not lonol foroot Slrendllno lake -lIoooe,black be.r -25 to SO porcont ..ergl--Neetlng end IIIOlt Ing h.bltot nel fermlng .0110 oreo -Grizzly boer _present ~_•Alpl",,-tundre~ -None present •Goad to high 'Iuo1lty scenery -Primitive lends -!lone ldenllfled -None Illentl fled falkeelnn 2 Cacho falllno -Block and Grizzly beor pr.ent -Moo88 foil/winter con- centration orca -Cor lbou winter range -Block end GriZZly beor present -fobooe wtnter concen- trot ion ares -C.ribou winter range -Block and Gr Izzly be.r preoent -tbose winter range -Caribou wlntar range -Nona ldont I f10d -None ldentl fled -Nona ident I fled -lowlend spruca-herdwood foresl -None ldont IfI"d -None ldentl fled -Nodi ...denalty w.ter- rowl area -Neotlng and 11IO 11 Ing eres -four epec iee present, one species spnwno at. alte -Four opoctes or aalmon preoont.spawn log oroos ldontlfled -Two speciee pre..nt at .110 end up.tre... -Coed to high 'lUoHty sceMry -Primitive lando ~Coed to high qu.llty scenery -Primitive lando -None identl fled -1Io0ting potontlol -Ilo.tlng potentlel -1Io01lng potent 101 -Nona ldent I fl.d -None IdentHled -None ldentl fled foklcl1llno -Black bear prosenl -",re lhan ~o percent of -HodilP density water--rour species present, -Hoose present oolls are usable for fowl orca three 8peciea &pawn in -Caribou prooent farming (In upper lando)-Neatlng .nd ..,ltlllll aroa ~alte vicInity -Border prbllit lve orea -Booting potentl.1 -!lone ldent tr led IABlE C.6 (Conllnued) ~~---~.__.__..--~-_._--_.--~~--------~-------t:Viiliiiil.-IOn----crnerTo Agr hiultiJriil liiiterrolil;-Replor.,--PiiiKJrOlllOfla Olg Came Polenllal ~_~Endangored SpecIes n""eriea Wilderness CuHufaI"Recreational,Restricted Conaldorsllon ond ScionlHlc nnllories lond llM JunllJlter8 -Black boar hoblla!-None ldonll fled -Nona ldenllfled -None Idsnllrled -Doll &h..p hobltot Upper Belugn -Moose prescnt -Hare thon ~O percent of -MadlUlll donslty ..nter--rOUf species present, upper londs are tlUlt-fowl area two species spawn In able for forming -Noollng ond moiling oreo -lowland spruce-hordwood oreo rorest Uppor No 11 Ie -Gr izzly boor present -None ldenl Hied -Nono Idsntlfled -None ldonll fled Jusn -Moose present -C089Ln1 western hemlock- -mock besr hobltat sitko spurce foroot -Sr lecled ror wllderne..-Nona ldonll ned conslderst Ion -Good 10 high quality scenery -Natural rcotureD -Primitive lendo -None Idsntl fled -Bostlng ores -Selecled ror "Ildsrno..-Oo.llng petentlol cono Idetat Ion -High pr Imltlvo,ocenlc, ond nslural roatureo -localed In Kenai Notional Masoe R"""" -Site ..lthln 0 - doolgnoled Nat Ions I WI tdernco8 orea -None ldenll ned -Chugach Nat lonnl Forest Whiskers -Bleck ond Crlzzly bear -50 percanl or upperland.-lo..don.lly "oterro..l prescnt suitable for farming nr08 -Mooo.pre.ent -Oollomlond spurce--Noollng ond molting -Cac lbou prosent.poplar forest area -five speclos present. two spawn In area -None Idsntlrted -Oostlng petenllel -No""ldentl ned Yentno -Block .nd Crlzzly boer present -~ose,spring/summar/ wlnler :oneent rot ton -25 to 50 percenl or -HodlUlll donslty ..eler- 00 Us In lowl nods ere fowl orea .ulteble ror r.rmlng -""'.Ung .nd moltIng -OoU...lond .pruce-popler eree forest -rive species spawn In orea -None Idsnl tried -Geatlng petenUsl -Nono Identified TABLE C.7 -SITE EVALUATION MATRIX Waterfowl,Installed [000 Big Agrlcullural Raplors,Anadromous Wilderness Cult,Recrea,Reslricted Capacity Dam nooded Game Polentisl Endg.Species rtsheries Consideration u&!iJ:i""tiLic Land Use Access (M'lI)Scheme Height (ft)(Acres) Crescenl lake Chakachomna lower Be I uga Coffee l\1per Beluga St rand line lake llrodley lake Kasilof River TustlJlleno Kenai lower Kenoi loke Crescenl lake-2 Granl lake Snow I-\CClure lley C C C C C C C C C C o C 11 B o o o o II II C C B o B o o o o o o C C C C C II C o C C C C C o B C B B B o o II o B B c II o C C B o o D C C o B C C C c o B C C C C C o C C o C o c c c o II B o o o o o o o B c C C c C B c o o o o o o B o o o o o c >100 <25 25-100 25-100 <25 25-100 <25 25-100 >100 <25 <25 25-100 <25 Reservo ir <150 wlOi vers ion Reservoir <150 wlOI vers ion Reservoir <150 anel Dam Dam snd <150 Reservoir Dam and 150-350 Reservoir Reservoir <150 wlOi version Reservoir <150 wlOi vers Ion Reservoir 150-350 wlOi vers ion Reservoir <150 w/Oiversion Om end <150 Reservoir Osm and >350 Reservoir Reservoir <150 wlOi vera ion Reservoir <150 wlOI vers Ion Reservoir 150-350 wlOi vers Ion Reservoir <150 wiD I vers ion <5000 <5000 <5000 <5000 5000 to 100,000 <5000 <5000 >100,000 <5000 <5000 5000 to 100,000 <5000 <5000 5000 to 100,000 <5000 l\1per Nellie Juan R C o o o B c C <25 Reservoir <150 w/Ohers Ion <5000 Allison Creek Solomon Gulch Lowe Sliver lake Power Creek o o C o o o o o o o R B R o R C C C C A o o c c c o o c c C o o o C c o o o c c <25 <25 25-100 <25 <25 Reservoir <150 w/Olversion Reservoir <150 wlOi vers ion Dam and 150-350 Reservoir Reservoir <150 wlOi vers ion Reservoir <150 wlOi vers Ion <5000 <5000 5000 to 100,000 <5000 <5000 Mill ion Dollar o o o A o c c c Dam and Reservoir <150 5000 to 100,000 Haterfowl,Installed nlimd 81g Agrlcullural Raplors,Anadromous Wilderness Cull,Recrea,Realrlcled Capacity Oorn rtoodod Game Polential Endg.Species fisheries Consideration &ScJ~nJ!fic Land lls~A,,-c"!llL__Q!lI.L s.,h~me Heighl (fl)(Acres) Keelna Grsnlle Gorge lalkeelna-2 Greenstone Cache Hicks B 8 8 8 8 B o o o o D D o o D D D c 8 8 8 8 B o o c c c C D c c c c C D o o o o o o c c c c c D 25-100 25-100 25-100 25-100 25-100 25-100 Oam and )350 Reservoir Reservoir 150-350 wiD I ve ra ion Dam and )350 Reaervoir Reservo I r 150-350 w/Di vera Ion Dum and 150-350 Reservblr Darn and 150-350 Reservoir 5000 10 100,000 <5000 5000 10 100,000 <5000 <5000 <5000 Ramparl Vachon Is land Juncllon Island Kanllshna River McKinley River Tsklanlka River 8rowne Healy Carlo Yanerl-2 8ruskasna Tanana Gerslle Johnson Calhedral Bluffs c 8 B c 8 8 B 8 B B B 8 fl c B 8 B 8 B D D c c D o o fl 8 B c 8 c C c C D o D o o C c C c c A A A 8 o D D o o o o B c C c o o D D B 8 D 8 8 B o D D o o C c C c c o c 8 c C B c c c I> C o o o A A o A A A o o o o o c C C B D o o o D o C D D )100 )100 )100 25-100 )1£10 25-100 25-100 25-100 )100 >100 Dam and Reservoir Dam and Reservoir Dam and Reservoir Oom and Reservoir Dam and Reservoir Oom and Reservoir Dam and Reservoir Oem ond Reservoir Darn and Reservoir Oumond Reaervolr Oumond Reservoir Dam and Reservoir Oem and Reservoir Dam and Reservoir Oam and Reaervoir )350 <150 150-350 <150 150-350 )350 150-350 150-350 150-350 150-350 150-350 <150 <150 <150 150-350 )100,000 )100,000 )100,000 )100,000 <5000 5000 to 100,000 5000 10 100,000 5000 to 100,000 <5000 5000 to 100,000 5000 10 100,000 5000 to 100,000 <5000 5000 to 100,000 5000 to 100,000 TABLE C.7 (Continued) WilterfOWl,··Installed Lililil Big Agricullural Raptors,Anadromous Wilderness Cull,Recrea,Reatrlcted Capacity Dam flooded _________Game Potential Endg.Species fisher lea Consideration c\Scientific Land Use Access (MW)Scheme Height (ft)(Acres) Cleave Wood Canyon lebay Lake Hanaglta C C C C o o o o B C o o B B C o B B B B C B o o A A A A o o n n Dam and 150-350 Reservoir Dam and >350 Reservoir Reservoir <150 w/Ol vers Ion Reservoir <150 ,,/Oi vers ion 5000 to 100,000 >100,000 <5IJOO <5000 Klutina Tazl Ina Gakona Sanford B Il o B C o C C c C C C C C C C B o o o C C C C o C A A o o 25-100 >100 Dam end Reservoir Oem and Reservoir Oem and Reservoir 150-350 150-350 5000 to 100,000 5000 to 100,000 r.ulkana Yentna To lachu It no SkwenLna Lake Creek Lpper Lake Creek Lower B B B B C C o B n B o n C C C C C C C B Il n C B o o o o C o B C C C o C B o o o A o o C c C c c 25-100 >100 25-100 25-100 Reservoir 150-350 w/Ol vers ion Oam and <150 Reservoir Oem end <150 Reservoir Oem and >350 Reservoir Reservoir <150 w/Ol vera Ion Oem and 150-350 Reservoir 5000 to 100,000 >100,000 5000 to 100,000 5000 to 100,000 <5000 <5000 Lower Chulitna Toklchitna COAL lJ110 Chulitna Whiskers lane C C Il B A C C B A o o o B B C C C C C C c B n C C C B n C C C C C o o C C C C C C c o o o o o o o o o o o o C C 25-100 >100 25-100 25-100 25-100 25-100 >100 Oem and Reservoir Oam ond Reservoir Dam end Reservoir Oam ond Reservoir Oem and Reservoir Oem end Reservoir Oom and 150-350 150-350 150-350 150-350 150-350 <150 150-350 <5000 5000 to 100,000 <5000 <5000 <5000 <5000 <5000 TABLEC.8-CRITERIAWEIGHTADJUSTMENTSDamHeightAdjustedWeightsReserv.AreaInitialWeight++++++++++++BigGame8678AgriculturalPotential7567Birds8678Fisheries108 910TABLEC.9-SITECAPACITYGROUPSNo.ofSItesNo.ofSItesSiteGroupEvaluatedAccepted<25MW5325-100MW154 - 6>100MW84 TABLEC.l0-RANKINGRESULTSSiteGroupPartialScoreTotalScoreSites:<25MWStrandlineLake5985NellieJuanUpper3796Tustumena37106AllisonCreek6582SilverLake65111Sites:25-100MWHicks6279Bruskasna71104BradleyLake71104Snow71106Cache86127Lowe89122Keetna89131Talkeetna-298134Coffee101126Whiskers101134Klutina101142LowerChulitiua106139BelugaUpper117142TalachultnaRiver126159Skwentna136169Sites>100MWChakachamna65134Browne6994Tazlina89124Johnson96121CathedralBluffs101126Lane106139KenaiLake112147Tokichitna117150 TABLEC.11-SHORTLISTEDSITESEnvironmentalCapacityRatingo -25MW25-100MW100MWGoodStrandlineLake*Hicks*Browne*AllisonCreek*Snow*JohnsonTustumenaCache*SilverLakeBruskasna*AcceptableKeetna*Chakachamna*PoorTalkeetna-2*LaneLowerChulitnaTokichitna*10selectedsites TableC.12-PRELIMINARYCOSTESTIMATE-SNOWDescriptionDiversionTunnelEarthCofferdamsExcavation-Overburden-SpillwayImperviousFillPerviousFillFilterStoneCoarseRockFillConcreteSpillway9Ft~PowerTunnel22Ft~SurgeShaft50MWUndergroundPowerhouseTailraceTunnelTailraceChannelSubtotalLand/DamagesReservoirClearingSwitchyardTransmissionRoadsBridgesOn-siteRoadsBuildings/EquipmentMobilizationSubtotalCampCateringSubtotalEngineering,AdministrationContingencyTOTALQuantity2,000132,000768,000638,0003,028,00083,00057,0001,60010,00020015052,000Cost/UnltUnit$LF3,060.00cy10.25cy4.50cy5.00cy5.00cy8.00cy8.50LF24,900.00LF1,978.00VLF7,000.00eaLF1,978.00LF510.00Airio~ntTotgls$10$106.121.353.463.1915.140.660.4939.8019.781.4025.001.001.02118.41.984.163.007.204.205.008.007.54158.4920.0014.40192.8961.72254.61 TableC.13-PRELIMINARYCOSTESTIMATE-KEETNACost/UnitAmo~ntfotglsDescriptionQuantityUnitJ$10$10DiversionTunnel2,000LF9,460.0018.92EarthCofferdams824,000cy10.258.45Excavation-Overburden1,474,000cy4.506.63ImperviousDamFill1,850,000cy5.009.25PerviousDamFill8,513,000cy5.0042.50FilterStone193,000cy8.001.54CoarseRock-RipRap148,000cy8.501.26Spillway Excavation410,000cy130FtConcreteSpillway1,000LF100,500.00100.50PowerTunnel2,100LF4,110.008.64100MWSurfacePowerhouse1ea50.00Subtotal247.69Lands/Damage1.66ReservoirClearing12.18Switchyard3.00Transmission3.20Roads3.60Bridges5.00On-siteRoads5.00Buildings/Equipment8.00Mobilization14.47Subtotal303.80Camp30.00Catering27.30Subtotal361.10Engineering,Administration,Contingency115.55TOTAL476.65 TableC.14-PRELIMINARYCOSTESTIMATE-CACHECostfUnltAffio~ntTot~lsDescriptionQuantityUnit$$10 $10DiversionTunnel2,200LF8,390.0018.45EarthCofferdams301,000cy10.253.09Excavation-Overburden2,946,000cy4.5013.25-Spillway490,000cyImperviousFill2,750,000cy5.0013.75PerviousFill12,018,000cy5.0060.09FilterStone284,000cy8.002.27CoarseRockFill196,000cy8.501.67ConcreteSpillway2,000LF71,400.00142.8013Ft~PowerTunnel2,000LF2,870.005.7450MWSurfacePowerhouse1ea25.00Subtotal286.11Lands/Damages1.89ReservoirClearing13.96Switchyard3.00Transmission8.80Roads12.00Bridges5.00On-siteRoads5.00Buildings/Equipment8.00Mobilization17.19Subtotal360.95Camp33.75Catering32.40Subtotal427.10Engineering,Administration,Contingency136.67TOTAL563.77 TableC.15-PRELIMINARYCOSTESTIMATE-BROWNECost/UmtAmo~ntTotglsDescriptionQuantityUnit$$10$10DiversionTunnel1,000LF12,000.0012.00EarthCofferdams196,000cy10.252.00Excavation-Overburden7,197,000cy4.5032.39-SpillwayImperviousFill2,497,000cy5.0012.49PerviousFill.11,895,000cy5.0059.48FilterStone337,000cy8.002.70CoarseRockFill329,000cy8.502.80ConcreteSpillway1,100LF128,000.00141.0023Ft~PowerTunnel1,000LF5,540.005.54100MWSurfacePowerhouse1ea50.00TailraceChannel300LF510.000.15Subtotal320.55Lands/Damages4.62ReservoirClearing28.21Switchyard3.00Transmission2.00Roads4.20Bridges5.00On-siteRoads5.00Buildings/Equipment8.00Mobilization19.03Subtotal399.61Camp37.50Catering36.00Subtotal473.11Engineering,Administration,Contingency151.40TOTAL624.51 TableC.16-PRELIMINARYCOSTESTIMATE-TALKEETNA-2Cost/UnItAffio~ntTot~lsDescriptionQuantityUnit$$10$10Diversion,Tunnel2,800LF8,660.0024.25EarthCofferdams445,000cy10.254.56Excavation-Overburden4,668,000cy4.5021.00-Spillway333,000cyImperviousFill2,932,000cy5.0014.66PerviousFill14,213,000cy5.0071.07FilterStone294,000cy8.002.35CoarseRockFill197,000cy8.501.67ConcreteSpillway1,200LF81,600.0097.9012.5Ft~PowerTunnel2,400LF2,750.006.6050MWSurfacePowerhouse1ea25.00Subtotal269.06Lands/Damages0.48ReservoirClearing3.27Switchyard3.00Transmission5.60Roads7.20Bridges5.00On-siteRoads5.00Buildings/Equipment8.00Mobilization15.33Subtotal321.94Camp27.50Catering29.10Subtotal378.54Engineering,Administration,Contingency121.13TOTAL499.67 TableC.17-PRELIMINARYCOSTESTIMATE-HICKSCost/UnItAirio~ntlotalsDescriptionQuantityUnit$$10 $106DiversionTunnel2,400LF8,450.0020.28EarthCofferdams641,000cy10.256.60Excavation-Overburden2,136,000cy4.509.60-Spillway292,000cyImperviousFill2,160,000cy5.0010.80PerviousFill8,713,000cy5.0043.60FilterStone238,000cy8.001.90CoarseRockFill154,000cy8.501.30ConcreteSpillway1,800LF79,444.00143.0015Ft~PowerTunnel1,900LF3,342.006.35SurgeShaft60MWSurfacePowerhouseea30.00Subtotal273.43Lands/Damages1.76ReservoirClearing1.48Switchyard3.00Transmission20.00Roads3.00Bridges5.00On-siteRoads5.00Buildings/Equipment8.00Mobilization16.05Subtotal336.72Camp33.75Catering30.30Subtotal400.77Engineering,Administration,Contingency128.25TOTAL529.02 TableC.18-PRELIMINARYCOSTESTIMATE-CHAKACHAMNACOst/Om.tAlriogntlotgIsDescriptionQuantityUnit$$10$10MainDamea2.0026FtConcreteLinedPowerTunnel57,000LF8,380.00477.66AditTunnels14,000LF1,680.0023.5035FtTailraceTunnel1,000LF3,500.003.5088Ft0SurgeShaft500LF50,000.0025.0016Ft0Penstocks3,700LF5,090.0018.85500MWUndergroundPowerhouse1ea273.50DiversionTunnel2,000LF9,580.0019.15Subtotal843.16Lands/Damages0.50ReservoirClearingSwitchyard3.00Transmission14.00Roads31.80Bridges10.00On-siteRoads10.00Buildings/Equipment8.00Mobilization44.40Subtotal964.86Camp72.50Catering84.00Subtotal1121.36Engineering,Administration,Contingency359.05TOTAL1480.41 TableC.19-OPERATINGANDECONOMICPARAMETERSFORSELECTEDHYDROELECTRICPLANTSMax.AverageEconomicGrossInstalledAnnualPlantCapit~lCostofHeadCapacityEnerrFactorCos~EnergyNo.SiteRiverFt.(MW)(Gwh(%)($10)($/1000Kwh)1SnowSnow6905022050255452BruskasnaNenana23530140532381133KeetnaTalkeetna33010039545477474CacheTalkeetna31050220515641005BrowneNenana19510041047625596Talkeetna-2Talkeetna3505021550500907HicksMatanuska2756024546529848ChakachamnaChakachatna9455001925441480309AllisonAllisonCreek1270833475412510StrandlineLakeBeluga810208549126115NOTES:~ncludingengineeringandowner'sadministrativecostsbutexcludingAFDC. TABLEC.20-ALTERNATIVEHYDRODEVELOPMENTPLANSInstalledOn-linePlanDescriptionCapacityDateA.1D1akachamna5001993Keetna1001997A.2D1akachamna5001993Keetna1001997Snow502002A.3D1akachamna5001993Keetna1001996Snow501998Strandline201998AllisonCreek81998A.4D1akachamna5001993Keetna1001996Snow502002Strandline202002AllisonCreek82002A.5D1akachamna5001993Keetna1001996Snow502002Talkeetna- 2502002Cache502002Strandline202002AllisonCreek82002 TABLE C.21 -RESULTS OF ECONOMIC ANALYSES OF ALTERNATIVE GENERATION SCENARIOS Installed capacity (MW)by 10tal System lotal System Category in 2010 Installed Present Worth Generation Scenario OGP5 Run 2hermal HYdro Capacity in Cost - ,~Descnption Load Forecast Id.No.oal Gas oil 2010 (MW)($10 6 ) All Thermal No Renewals Very Low 1 LBT7 500 426 90 144 1160 4930 No Renewals Low L7E1 700 300 40 144 1385 5920 With Renewals Low L2C7 600 657 30 144 1431 5910 No Renewals Medium LME1 900 801 50 144 1895 8130 With Renewals Medium LME3 900 807 40 144 1891 8110 No Renewals High L7F7 2000 1176 50 144 3370 13520 With Renewals High L2E9 2000 576 130 144 3306 13630 No Renewals Probab il ist ic LOF3 1100 1176 100 144 3120 8320 Thermal Plus No Renewals Plus:Medium l7W1 600 576 70 744 1990 7080 Alternative Chakachamna (500)2_1993 Hydro Keetna (100)-1997 No Renewals Plus:Medium LFL7 700 501 10 794 2005 7040 Chakachamna (500)-1993 Keetna (100)-1997 Snow (50)-2002 No Renewals Plus:Medium LWP7 500 576 60 822 1958 7064 Chakachamna (500)-1993 Keetna (100)-1996 St randl.i.ne (20), Allison Creek (8), Snow (50)-1998 No Renewals Plus:Medium LXF1 700 426 30 822 1978 7041 Chakachamna (500)-1993 Keetna (100)-1996 Strandline (20), Allison Creek (8), Snow (50)-2002 No Renewals Plus:Medium L403 500 576 30 922 2028 7088 Chakachamna (500)-1993 Keetna (100)-1996 Snow (50),Cache (50), Allison Creek (8), Talkeetna-2 (50), Strandline (20)-2002 Notes: (1)Incorporating load management and conservation (2)Installed capacity 46SCALE-MILESIINCHEQUALSAPPROXIMATELY40MILESo&G0-25MW25-100MWI.STRANOLINEL.13.WHISKERS26.SNOW2.LOWERBELUGA14.COAL27.KENAILOWER3.LOWERLAKECR.15.CHULITNA28.GERSTLE4.ALLISONCR.16.OHIO29.TANANAR.5.CRESCENTLAKE217.LOWERCHULITNA30.8RUSKASNA6.GRANTLAKE18.CACHE31.KANTISHNAR.7.McCLURE8AY19.GREENSTONE32.UPPER8ELUGA8.UPPERNELLIEJUAN20.TALKEETNA233.COFFEE9.POWERCREEK21.GRANITEGORGE34.GULKANAR.10.SILVERLAKE22.KEETNA35.KLUTINAII.SOLOMONGULCH23.SHEEPCREEK36.BRADLEYLAKE12.TUSTUMENA24.SKWENTNA37.HICK'SSITE25.TALACHULITNA38.LOWESELECTEDALTERNATIVEHYDROELECTRICSITES39.40.41.42.43.44.45.46.47-48.49.>100MWLANETOKICHITNAYENTNACATHEDRALBLUFFSJOHNSONBROWNEJUNCTIONIS.VACHONIS.TAZILNAKENAILAKECHAKACHAMNAFIGURECIIOIRI FIGUREC.2[iii]~CALE.: 0'200400FEETI~~~!~_~IGRA\JE.LSURF~E:CCRESTELEVATION(ASINDICATEDONPLAN)~=#=:::o...::::--...L.---DAMCROSSSECTiONALTERNATIVEHYDROSITESTYPICALDAMSECTIONRIPRAP£NORMALMAx.WL(ASINDICATEDONPLAN) FIGUREC.314TAILRACEUNDERGROUNDPOWERHOUSE50MWCAPACIToSCALE:AO,----r=1~O.ZM\LES•ISCALE:BI;iMILESALTERNATIVEHYDROSITESSNOWPLANOFDEVELOPMENT,,00;;~==~S:C~A~LE~:~B~=::=-__---!~~J\'l,00..-0:-::::-~~:;.------.-.......;::;-..:::::"'.-:::::---------:::-,...::::---.----------"---:::---°08~//\ooo\o8 FIGUREC.4111m:...----..'"--"-----•..SURFACE.FOWe.R1-lOUS1:rooMWCAPACITY1=L1PBUCKl:iITAlkWATERSt...~~.s.o/l~.-----0/5:COFFERDAM.p~RINTAKIii(\\ALTERNATIVEHYDROSITESKEETNANORMAl..MA')(,W.L.EL.0)45t FIGUREC.5\500\600.___-liOOSURF~CEPOWtRHOUSE.50MWCAPACITY\~oo~ALf:0~~~~~O_.I~..'2.I.•MILe>-----SP\LLWA'YCONTROL~\<cfSJSTRUCTURE.~ALTERNATIVEHYDROSITESCACHE---------.,.".-:-....NORMALMA'J..WLE.L.\630-~-----------._-\400~•••uf.;COFFERDAM~------....".-------1400-.~-•• FIGUREC611~lmI0.2MILES0.1o/#/,.....",,----_...----.F'LIPOUC~ET FIGUREC.7O.'2.MIL.E.S0.1SCAl-E:.0\?JcP0°\J\:~POWERTUNNE.-LALTERNATIVEHYDROSITESTALKEETNA2SPILl-WA'(CONTROL.~__STt<U<:TuRe.\'OC~~=------'Soc-~--U!sCOFFE:ROAJv1/,\cP1000-~-------1400/1iI'ooFLOWr> AGUREc.a[iii]1800O.'2..M IL.ES0.1---------------1900rzt:X:J::)SCALE.05PILL.WAYCONTROL5TJ<UCTURE........:::::::1-11----<:::::..·1-1....---.......-:-:.>.......1700__________lGOO:-------------=/50:::>--/9QJ~::I-It---l~---------~---------'2100---20~_---~----1800---==:::::::-~f---'~:-=-::::--:~--==----------------ALTERNATIVEHYDROSITESHICKS"DisGOFFIER.DAM,"1400"~...\~~~ISURFAcE.POWE.RHOUSe.-__=-nI.'.__~---~::T:\ttt=-----:"~'--II::"'-"~'/\.'''~,<00MWCAPAC1-:::__•••_....~"---.::J---..----.~~:~:~/.l---l!I------IT.o::~WATE.1<.E.LI~IIMATANUSkAeIVE.R".=4••I--II---~".....0.=-,.o~···--------···--':::=::::'0i~FLIPBUCKET-----/500r---_,<OQo-.U/5GOFFEROAMNORMALMAX.W.L.£L.I<aSGI o'2MIL.E.S~""--.""I....-..""r,CONSTRU110N--fAOITALTERNATIVEHYDROSITESCHAKACHAMNAUt-JDE:R.GROUNDPOWE'RHQUSe.-500MWCAPA.CITYFIGUREe.9 FIGUREC.IOIHimISURe;E5~AFT10II8UNLlt-JE.DORSHOTCR&TER:>WERTUNt-JEL2~.O:DIA.6..,TAILRAa:TDNNI:L5ALTERNATIVEHYDROSITESSeAL.,-0.......0:::.-----:.:;40FEETCHAKACHAMNA-PROFILEANDSECTIONSHORIZONTALDISTANCE.It-JMIL;S4PROFILEALONGiOFINrAKii::,TUNNI:L1~POWERI-4OUSE32powe~TUNN&LSECTIC),JMAXIMUMReSERVOIRELU30.0·oIUL",L.~____J---_L---_1_---_+_---+_---+_---~--~~--_+---+~-=~L_JF7TAlLWATGRla,/-B5li'\l--JJ-----+-----+-~--_+---+--"""7'""4'~--_t_---+_---+_---t_---t_---t_-_r___;-r-1'ONERHOUse500MW(;.AR6CITYFIGUREC.IOIHimISURe;E5~AFT10II8UNLlt-JE.DORSHOTCR&TER:>WERTUNt-JEL2~.O:DIA.6..,TAILRAa:TDNNI:L5ALTERNATIVEHYDROSITESSeAL.,-0.......0:::.-----:.:;40FEETCHAKACHAMNA-PROFILEANDSECTIONSHORIZONTALDISTANCE.It-JMIL;S4PROFILEALONGiOFINrAKii::,TUNNI:L1~POWERI-4OUSE32powe~TUNN&LSECTIC),JMAXIMUMReSERVOIRELU30.0·oIUL",L.~____J---_L---_1_---_+_---+_---+_---~--~~--_+---+~-=~L_JF7TAlLWATGRla,/-B5li'\l--JJ-----+-----+-~--_+---+--"""7'""4'~--_t_---+_---+_---t_---t_---t_-_r___;-r-1'ONERHOUse500MW(;.AR6CITY 2010700kl""'I""'III~",j1965J.L..'-Ll2000150815341944fllJll'l'I'lI1954PEAKLOAD~19807152oLEGEND8642DHYDROELECTRIChtrtilCOALFIREDTHERMALEZlGASFIREDTHERMAL•OILFIREDTHERMAL(NOTSHOWNONENERGYDIAGRAM)NOTE:RESULTSOBTAINEDFROMOGPSRUNLFL7KEETNACHAKACHAMNAEXISTINGANDCOMMITTEDSNOW1980199020002010TIMEGENERATIONSCENARIOINCORPORATINGTHERMALIlieIANDALTERNATIVEHYDROPOWERDEVELOPMENTS-MEDIUMLOADFORECAST-FIGUREC.II APPENDIX0 -ENGINEERINGLAYOUTDESIGNASSUMPTIONSTheobjectiveofdocumentingthefollowingdesignconsiderationsistofacili-tateastandarizedapproachtotheengineeringlayoutworkbeingdoneaspartofSubtasks6.02"InvestigateTunnelAlternative",6.03"EvaluateAlternativeSusitnaDevelopments"and6.06"StagedDevelopment".Itisemphasizedthatforpurposesoftheseinitialprojectdefinitionstudies,layoutsareessentiallyconceptualandthematerialpresentedisbasedonpublisheddatamodifiedbyjudgementandexperience.0.1-ApproachtoProjectDefinitionStudiesThegeneralapproachtotheprojectdefinitionstudiesinvolvesthreesteps:(a)SingleSiteDevelopmentsAllsitesaretreatedassingleprojects.(b)MultisiteDevelopmentsTwoorthreesitesaredevelopedinaseries.Thismeansthatthedown-stream·sitesmayhaveinstalledcapacities,spillwayanddiversioncapaci-ties,anddrawdownlevelswhichdifferconsiderablyfromtheslnglesitedevelopment.(c)StagedDevelopmentsDevelopmentatasitemaybestaged,i.e.insubsequentstagesofdevelop-ment,thedamcrestlevelmaybeincreasedandthepowerhousecapacityexpanded.Althoughthesestepsnormallyfollowconsecutively,thereisconsiderableover-lap,andworkcouldbeprogressingonallthreestepsatthesametime.Thisappendixessentiallyaddressesthestep(a)typestudies.Carefulinter-pretationoftheinformationisrequiredwhenapplyingittostep(b)and(c)studies.0.2-ElectricalSystemConsiderationsThecurrenttotalsystemplantfactorisreportedtobeoftheorderof50to55percent.Studyprojections(Section5)indicatethatthisfactormaygouptobetween56and63percentinfutureyears.Initially,allprojectsshouldbesizedfora45to55percentplantfactorandshouldincorporatedailypeakingtosatisfythisrequirement.Asalaterstep,someoftheproposeddevelopmentscouldhavehigherorlowerplactfactors,ifthisisjustifiedineconomicstudies.0-1 Allprojectsshouldbecapableofmeetingaseasonallyvaryingpowerdemand.TableD.1isbasedonloadforecastingstudiesundertakenasdiscussedinSection5andliststhemonthlyvariationinpowerandenergydemandthatshouldbeused.Ingeneral,theinstalledcapacityandreservoirlevelregulatingrulesusedinthisstudyareestablishedsothatthefirmenergyoutputoftheprojectismaximized.Anumberoftermsrelativetoenergyassessmentswhichareusedintheprojectdefinitionstudiesarelistedanddefinedbelow.Thesedefinitionsmaybemodifiedduringthesubsequentstepsofthefeasibilitystudiestoreflectthehighersophisticationofthestudiesandconsequentlytheneedforamoreexactorspecificterminologydefinition.-AverageMonthlyorAnnualEnergyTheaveragemonthlyannualenergyproducedbyahydroprojectoveragivenperiodofoperation.-FirmMonthlyorAnnualEnergyTheminimumamountofmonthlyorannualenergythatcanbeguaranteedevenduringlowflowperiods.Forpurposesofthispreliminarystudythisshouldcorrespondtotheenergyproducedduringthesecondlowestenergyproducingyearonrecord.Thiscorrespondsroughlytoanannuallevelofassuranceof95%.-SecondaryEnergyElectricenergyhavinglimitedavailability.In900dwateryearsahydroplantcangenerateenergyinexcessofitsfirmenergycapability.Thisexcessenergyisclassifiedassecondaryenergybecauseitisnotavailableeveryyear,andvariesinmagnitudeinthoseyearswhenitisavailable.-InstalledCapacityTheratingofgeneratorsatdesignheadandbestgateavailableforproductionofsaleablepower.D.3-GeotechnicalConsiderations(a)MainandSaddleDamsGeotechnicalconsiderationsinherentforeachofthedamsitesaresummarizedinTableD.2.(b)TemporaryCofferdamsItisassumedthatallcofferdamsareoffill-type.Sincemuchoftheoriginalriverbedmaterialunderthemaindamshellmayhavetobeexca-vated,allcofferdamshavebeenlocatedoutsidetheupstreamanddownstreamlimitsofthemaindamineachcase.D-2 D.4-HydrologicandHydraulicConsiderationsTablesD.3,D.4,D.5andD.6listtheprovisionalhydrologicandhydraulicparametersusedininitialprojectdefinitionstudies.TableD.7detailspreliminaryfreeboardrequirements.AnexampleisworkedoutinTableD.8tocalculatefreeboardrequirements.(a)GeneralFiguresD.1toD.8illustratethestoragecapacityandreservoirareaateachSusitnaBasindamsitefortheapplicablerangeofwaterlevels.(b)SizingofHydraulicComponentsPowerConduits-FordamschemesthesizesshouldbebasedonthemaximumvelocitieslistedinTableD.6.Forlongtunnelschemesthediameterisdeterminedsuchthatthecostofenergyisminimized.Thatis,tunneldiameterisoptimizedbetweencostofexcavatinglargertunnelsagainstreducedheadlosses.-DiversionSystem-Thecofferdam-diversiontunnelsystemissizedasfo11ows:•Thediversiontunnelissizedtoaccommodatethemaximumvelocitypermissible(TableD.6)forthedesigndiversionflow.Thetopoftheupstreamcofferdamisthendeterminedbycomputingheadlossthroughthetunnel,addingtotheelevationoftheenergygradelineattheoutletportal,andprovidinga10feetfreeboardallowance.•Thedownstreamcofferdamheightisdeterminedfromtheavailablestage-dischargerelationshipwithsimilarfreeboardallowances.-Spillway-SpillwaysizewasbasedontheaccommodationoftheProjectDesignFloodshowninTableD.3andD.4.Supplementaryemergencyspillwaysareusedwherenecessary.Allservicespillwayshavedownstreamstillingbasins.ThecapacityofeachstructureischeckedforthePMFflowwithareductionupto9feetinfreeboard(TableD.7).Theenergytobedissipatedbythespillwaystructurewassetat45,000hpperfootwidthunderPMFconditions.D.5-EngineeringLayoutConsiderationsTableD.9liststhecomponentsthatareincorporatedintheengineeringlayoutsanddescribesthetypesofcomponentstobeused.TableD.9wasusedasaguidetodesignforalllayouts.D.6-MechanicalEquipment(a)Powerhouse-NumberofUnitsIngeneral,adecreaseinthenumberofunitswillresultinareductioninpowerplantcost.ForpreliminarystudiesithasbeenassumedthatunitcapacitiesrangefromIOOto250MW.Theminimumnumberofunitsassumedistwoandthemaximumnumberisfour.D-3 -TurbinesTheratednetheadhasbeenassumedtobeapproximatelyequaltotheminimumnetheadplus75percentofthedifferencebetweenthemaximumandminimumnetheads.Forratedheadsabove130feet,verticalFrancistypeunitswithsteelspiralcaseshavebeenassumed.VerticalKaplanunitsareusedforheadslowerthan130feet.Turbinesaredirectlyconnectedtoverticalsynchronousgeneratorsinallcases.(b)OverflowSpillwayGatesThespillwaygateshavebeenassumedtobefixedwheelverticalliftgatesoperatedbyadoubledrumwithropehoistslocatedinanenclosedtowerandbridgestructure.Maximumgatesizeforpreliminarydesignhasbeensetat50feetwidthand60feetheight.Inallcasesaprovisionof3feetoffreeboardforgatesovermaximumoperatinglevelhasbeenassumed.Thegatesareheatedforwinteroperation.(c)MiscellaneousMechanicalEquipmentCostestimatesprovideforafullrangeofpowerstationequipmentincludingcranes,gates,valves,etc.0.7-ElectricalEquipment(a)PowerhouseGeneratorsareoftheverticalsynchronoustypewithseparatetransformergalleriesprovidedformainandstationtransformers.Provisionismadeinthecostestimatesforafullrangeofmiscellaneousoperatingandcontrolequipmentincludingwherenecessaryallowanceforremotestationoperations.(b)SwitchyardandTransmissionLinesTheswitchyardisdesignedtobelocatedonthesurfaceandasclosetothepowerhouseaspossible.Sizeguidelinesfortheyardsareapproximately900x500feet.Costestimatesallowfortransmissionlinesandsubstations(Table0.9).0.8-EnvironmentalConsiderationsPreviousinvestigationshaveshownthataprimeenvironmentalconsiderationistheeffectofpossibledevelopmentonfisheries.Inordertoavoidaseveredetrimentalimpactonthefisherieshabitat,tentativewaterlevelfluctuationsanddownstreamflowreleaseconstraintshavebeendeveloped.Theseareguidelinesonlyforthepresentstudiesandwillbefurtheraddressedandrefinedasworkproceeds.0-4 (a)FlowConstraintsTable0.10listspreliminaryvaluesofminimumflowsrequireddownstreamofanydevelopmentatalltimes.Thelowerflowsarebasedonpreliminaryassessmentoftherequirementsofresidentfishwhilethehigherflowsareestimatedanadromousfishneeds.(b)WaterLevelConstraintsDailyreservoirlevelfluctuationsshouldbekeptbelow5feetwhileseasonaldrawdownshouldbelimitedtobetween100and150feet.0-5 TABLE0.1-MONTHLYVARIATIONSOFENERGYANDPEAKPOWERDEMANDMonthEnergyVar2at2onPeakDemandOctober.086.80November.101.92December.1091.00January.100.92February.094.87March.086.78April.076.70May.069.64June.067.62July.066.61August.070.64September.076.70I,I~ General Conditions TABLE D.2 -GEOTECHNICAL DESIGN CONSIDERATIONS DAM S -rT E Dena!l Maclaren Vee Dam Type U!S Slope D!S Slope Earth-Rockfill 4:1 (H!V) 4:1 Earth-Rockfill 4:1 4:1 Earth-Rockfill 2.25:1 2:1 General Foundation Conditions All structures would have soil foundations.Depth to bedrock is believed to be 200'+.Inter- stratified till and alluvium foundation material,local liquefaction potential.40'+ alluvium in valley. Assurre soil foundations.Depth to bedrock estimated at 200'. Compressible,permeable and liquefiab Ie zones probab ly exist. River alluvium 125',drift abutments is 10-40'thick. located on deep permafrost or talus on Saddle dam alluvium. Required Foundation Excavation (in addition to overburden) Abutment Channel Total Excavation Depth Core Shell---mr-...,-rrr- 70''50' Unknown. Denali. Assume same as for Assume:Core -Remove rock Shell -Remove average of 50'of top 10'of rock Required Foundation Treatment and Grouting Seismic Considerations (MCE =Maximum Credibl e Earthquake) Powerhouse Locat ion Permafrost Construction Material Availabi lity Remarks NOTES: Assune core-grout in five rows of holes to 70 percent of head up to a maximum of 300 I. Probable drain curtain or drain blanket under downstream she II. Foundation surface -no special treatment. High exposure,no known site faults.MCE =Richter 8.5 @ 40 Underground powerhouse unsui tab Ie. >100 I deep in abutrrents,probable lenses under river. No borrow areas identified. Assume suitable materials are available within a five-mile radius.Processing of impervious material will be required. Based on Kachadoorian,1959. Assume same as for Denali. High exposure,no known site faults. MCE =8.5 @ 40 miles. Underground powerhouse unsuitable. Probably )100'. Assume same as for Denali. No report on site.Parameters based on regional geology. Assume grouting same as for Watana.No special treatment under shell.Assume extensive sand drains in saddle dam permafrost area. High exposure,no known site faults. MCE =B.5 @ 40 miles. Unknown.Assume suitable for t.l1derground with substantial rock support. >60'in saddle area,sporadic in ablJt- ments. Assume available 0.5 to 5 mile radius. Imperv ious will require processing. Based on USSR studies. Watana and Devil Canyon have been taken from overburden contour maps. to January 1 t 1981.Estimates made after this date have used updated excavation criteria. TABLE D.2 (Continued) General Conditions D--1\-M S I I t: 5lisTEna Watana HIgh Dev!l Canyon Dam Type U!S Slope D!S Slope General Foundation Conditions Required Foundation Excavation (in addition to overburden) Required Foundation Treatment and Grouting Seismic Considerations (MCE =Maximum Credible Earthquake) Powerhouse Location Permafrost Construction Material Availability Remarks Earth-Rockfi 11 2.25:1 2:1 Unknown but rock probab Ie over 50'in depth.Possible perme- ab Ie compressible and liquefiab Ie strata. Assurre same as for Watana. Assure grout and drain system full width of dam,dependent on founda- tion quality.Drain gallery and drain holes. High exposure.MCE=8.5 ®411 miles. Also near zone of intense shearing. Unknown.Assume suitable for underground with substantial rock support. Probably sporadic and deep. Assume available within five miles.Processing similar to that at Watana. No reports available.Parameters based on regional geology of the area. Earth-Rockfill or concrete arch 2.25:1 (for earth) 2:1 Abutments-assume 15'overburden (OB) Valley bottom -48-78'alluvium. Assume 70'.Right bank upstream - apprOXimately 475 t deep relict channel on right bank,upstream of dam site. Core:Remove top 40'of rock. Shell:Remove top 10'of rock. Extensive grouting to depth =7r110 of head but not to exceed 300'. Drain gallery and drain holes. MCE =Richter 8.5 ®40 miles or 7.0 @ 10 miles.- Underground favorab Ie,ex tensi ve support may be required. )100'on left abutment.More prevalent and deeper on north facing slopes. Available with 0-5 miles. Processing required. Based on Corps studies and 1980 Acres exploration. Earth-Rockfill 2.25:1 2:1 Assume 30-60'overburden and alluvium. Core:Remove top 40'of rock. Shell:Remove top 15'of rock. Assure same as for Watana. Same as for Watana. Probably favorable for underground but assume support needed. Sporadic,possibly 100'+. No borrow areas defined.Assume avail- able within 5 miles. No geotechnical data available.Para- meters based on regional geology. -~~~~~~~~~~~''-''?----=....'"m.........~~.__'" TABLE 0.2 (Continued) General Conditions DAM 5--1 T E De~Canyon Devl1 Canyon ~age Creek Dam Type U!S Slope D!S Slope General Foundation Conditions Required Foundation Excavation (in addition to overburden) Required Foundation Treatment and Grouting Concrete arch or gravity Assume 35'alluvium in river bottom. abutments,35-50'of weathered rock. deep.Assume excavation for spillway valley walls. Remove 50'of rock.Extensive dental work and shear zone over- excavat~on will be required. Saddle dam:Excavation 15'into rock. Extensive grouting to 70~~of head, limited to 300'.Allow for long anchors into rock for thrust blocks.Extensive dental treat- ment.Deep cutoff under saddle dam,15'into rock. Rockfill 2.25:1 2:1 Shears and fau 1t zones in both Saddle dam overburden up to 90' totals 90'to sound rock on Core:Excavation 40'into rock Shell:Excavate 15'into rock Extensive grouting to 70%of head, limited to 300'.Extensive dental treatment under core.Deep cutoff under s add Ie dam,15'into rock. Concrete gravity Unknown -assume same as for Devil Canyon Rock type is similar to Devil Canyon,so assume foundation condit ions are similar. Assume same as Devil Canyon. Seismic Considerations (MCE =Maximum Credible Earthquake) Powerhouse Location Permafrost Construction Material Availability Remarks Same as for Watana. Favorable for underground power- house,assume moderate support. None expected,but possibly sporadic. Concrete aggregate within 0.5 miles,embankment material - assume within 3 mi les. Based on USBR,Corps and 1980 Acres exploration. Same as Watana. Favorable for underground power- house,assume moderate support. None expected,but possibly sporadic. Concrete aggregate within 0.5 miles, embankment materia 1 -assume within 3 miles. Based on USBR,Corps and 1980 Acres exploration. MCE =Richter 8.5 @ 40 miles or 7.0 at 10 miles.- Probably favorable for underground powerhouse,assume moderate support. None expected,but may be local areas on north exposures or in overburden. Unknown -expect adequate sources 2-5 miles downstream. No previous investigations are available on this site. Parameter Denali .2Catchmentarea-sq.ml.:1,269' Mean annual flow-cfs:3,290 Spillway design flood-efs:89,800 Construction diversion flood cfs:42,500 50 year sediment accumulation Acre-ft 1 :*290,000 Notes: (1)Assumes upstream reservoir. TABLE D.3 -INITIAL HYDROLOGIC DESIGN CONSIDERATIONS DAM 5 I TE 5 Susitna High Devil Devil Portage Tunnel Maclaren Vee III Watana Canyon Canyon Creek Alternative Remarks 2,320 4,140 4,225 5,180 5,760 5,810 5,840 4,360 6,190 6,350 8,140 9,140 9,230 9,230 106,000 133,000 137,000 175,000 198,000 200,000 200,000 175,000 1:10,000 year flood peak without routing 50,000 63,000 64,600 82,600 93,500 94,400 20,0001 20,0001 1:50 year flood peak 243,000 162,000 165,000 204,000 248,000 252,000 ----assumes no up- stream develop- ment TABLE D.4 -REVISED DESIGN FLOOD FLOWS FOR COMBINED DEVELOPMENT Parameters ~v-r-[Qtl-M E N T Scnel1leT .--SCneme-L .~m-arKS (High Devil Portage ) (Watana &Devil Canyon)(Canyon &Creek &Vee ) Spillway design flood -cfs 115,or)Q 135,000 145,000 150,000 105,000 1:10,000 year flood routed through the reservoir at FSL as in Table D.5 Construction diversion 89,100 20,000 99,100 20,000 71,200 Subsequent developrrents enjoy regulation by upstream reservoir(s). PMF for checking 235,000 270,000 262,000 270,000 189,000 design -cfs Notes: This table is based on Acres Flood Frequency Analyses and supercedes Table D.3 for Watana and High Devil Canyon first developrrents. TABLE 0.5 -SITE SPECIFIC HYDRAULIC DESIGN CONSIDERATIONS 1JAM"5~TTt:--S Susitna High Devil Devil Portage1 Tunne1 1 Remarks Tunnel Parameter Denali Maclaren Vee III Watana Canyon Canyon Creek Alternative Alternative Only Reservoir Full 2,540 2,395 2,330 2,340 2,220/1,750 1,445 1,020 2,200/Tunnel alternative Supply Level -ft 2,000 1,475 consists of Watana and re-regu lat ion dams Dam Crest Level -'ft 2,555 2,405 2,350 2,360 2,225/1,775 1,465 1,030 2,225/See above remarks 2,fJ60 (rock fill)1,490 1,459 (concrete)2 Average Tail Water Level -ft 2,4fJ5 2,320 1,925 1,81 fJ 1,465 1,030 880 85fJ 1,465/Watana/Re-regula- 1,260/tion dam/Devil 9fJO Canyon,respec- tively Installed Capacity -MW 50 10 230 330 800/400 800 400 150 Maximum Power Flow -5,400 2,000 8,300 9,fJOO 18,000/18,000 10,000 15,000 8,400 In Tunnel between cfs 11,000 re-regulation and Devil Canyon Power House Minimum Compensation 600 1,200 1,500 1,500 2,000 2,000 2,000 2,00fl 1,000 In reach between Flow -cfs tunnel out fa 11 at Devil Canyon Low Level Outl~t 8,900 4,700 8,300 10,flOO 20,800 15,600 10,6orl 9,300 20,8flf)Capacity -cfs' Notes: (1)Considered only as second developments after u/s dam(s)is built. (2)Includes 4'high wave wall on top of dam. (3)Empties reservoir to ,10 percent capacity in 12 months. TABLED.G-GENERALHYDRAULICDESIGNCONSIDERATIONSWaterpassage1Steelpenstocks:Powertunnels-lined:Tailrace-lined:-unlined:Diversiontunnels-lined:MaXlmumVelocityfps2015151050Notes:(1)Fortunnel-alternativeschemes(tunnellengthgreaterthan5miles)optimizevelocitywithrespecttocostoftunnelingandenergylossinfriction. (1)Ifseismicslump<14'designconditionsfixdamcrestlevel.Ifseismicslump>14'damcrestleve1=FSL+seismicslump+1percentallowanceforpost-constructionsettlement.-TABLED.7-PRELIMINARYFREEBOARDREQUIREMENTParameterDesignConditionsDryfreeboard-ftWaverunupandwindsetup-ftFloodsurchargeoverfullsupplylevel(FSL)-ftAllowanceforpost-constructionsettlementTotalfreeboard-ftDamcrestlevel-ftExtremeConditionsforCheckingDesignSeismicslump1PMFsurchargeoverFSLallowableNotes:DAMRockhIllEarthfillDam3651%damheight14'FSL+14'+1%damheight1-1/2%ofdamheight14'YPEConcreteDam365nil14'FSL+14'nil14' TABLE0.8-EXAMPLECALCULATIONOFFREEBOARDREQUIREMENTATDEVILCANYONParameterDesignConditions1Dryfreeboard-ftWaverunupandwindsetup-ftFloodsurcharge-ftHeightofdam-ft1%ofheightforpost-constructionsettlementDamcrestlevelExtremeConditionsSeismicslump(1-1/2%)-ftSeismicslump<14feetThus,damcrestlevelremainsthesameascalculatedaboveDAMTY P ERockhl1ConcreteDamDam3366556006006nil1445+14+61445+14==1465'1459'9nilPMFconditionMaximumallowblewaterlevelNotes:1445+14=1459'1445+14=1459'(1)Fu11supplylevel=1445ft;damheight=600ft TABLE 0.9 -ENERGINEERING LAYOUT CONSIDERATIONS AS SINGLE DEVELOPMENTS U/l;WSTTE Components Denali Maclaren C1j Vee Susitna III Watana High Devil Canyon Devil Canyon Tunnel Alternatives Dam t--Conventional earth/rockfill--------------------------------------·--------Concrete Earth/rockfill Spillway Power Facilities Intake: Power Tunnel: Penstocks: Powerhouse: Tailrace Tunnel: Low Level Outlet Works Intake and Tunnel: t--Service:Gated,open chute with downstream stilling basing --7 t--Emergency:(if required)as above with downstream flip bucket ) ~Single level ----7 f--Multilevel ) f--Single concrete"?f--Minimum of two,concrete lined Two partially lined lined tunnels (1/3 concrete lined,1/3 shot- creted,1/3 unlined) f--Steel lining where necessary (near U.G.Powerhouse)(length =1/5 turbine head)) t--Underground if feasible f-One lined/unlined ----1 f---Two lined/unlined ) (Lined or unlined -based on cost/energy loss optimization f-One or two with gates -use diversion tunnel(s)if possible ) Construction Facilities U/S &D/S Cofferdams:f--Earth or rock fill ) Fill or~cellular-)f--Fill------\) Diversion Tunnels: Access Road Access: Transmission Line Local Compensation Flow Outlet Surge Chamber Notes: t--Minimum of two ) t--To Denali Highway ----1 t---to Gold Creek ) t-To Cantwell along ----7 f--to Gold Creek ) Denali Highway t--Roads/tunnels and bridges as required ) t-Independent intake with control valve discharghing through low level outlet works or independent conduit ) t--Upstream surge tank required if net head on machines <1/6 of distance between reservoir and machine ) f--Downstream surge tank is required if tailrace is pressurized ) ~Size differential surge chambers for all locations where required ) (1 )Portage Creek development will be similar to Maclaren except that access roads and transmission lines will be to Gold Creek. TABLE D.10 -TENTATIVE ENVIRONMENTAL FLOW CONSTRAINTS Site lfeCjlui'ea MInImum Flow Release -cfs WfEh ProTect--.Wl1::Il-otJtProje-ct Located Located Downstream 1 Downstream 1 Maximum Allowable Flow for Daily Peaking O~erations CFS Remarks Dena Ii Maclaren Vee Susitna III Watana High Devil Canyon Devil Canyon Alternative Tunnel Scheme Notes: 300 600 600 1,20fl 800 1,500 800 1,500 1,000 2,000 1,000 2,000 1,flOO 2,000 1,flOO 5,000 6,500 9,500 9,500 12,000 13,500 14,000 14,000 In the reach between re-reg.dam and tail- race outfall at Devil Canyon (1)Does not apply if downstream dam backs up to tail water level of dam above. (2)Would not necessarily apply if scheme considered did not include a substantial amount of seasonal regulation. APPENDIXE-SUSITNABASINSCREENINGMODELAsdiscussedinSection8,ascreeningmodelwasdevelopedforuseintheselec-tionofSusitnaBasinsitesforincorporationinthebasindevelopmentplans.ThepurposeofthisAppendixistoprovidetherequiredbackgroundinformationnecessarytoestablishthevalidityandreasonablenessofthescreeningmodelusedtodeterminetheseoptimumbasindevelopmentsfortheselectionprocess.Asinmostmodelswhichtrytooptimizeadesiredproduct,thescreeningmodelisdependentupontheavailabilityanddetailofinformationusedasinput.Thescreeningmodelisthereforeonlyasgoodastheinputestimatesofcost,damtypes,environmentalcriteria,andenergyoutputandrequirements.Theuseofthemodelshouldthereforebetreatedinasubjectivemannerappropriatetothequalityoftheinputdataused.E.l-ScreeningModelThebasicscreeningmodelisausefultool,evenwhendatabasesarethoughtinadequateorincomplete.Theusefulnessofthemodelstemsfromitsabilitytorejectalternativesthatareobviouslyinferiortoothersandtorankallalter-nativesaccordingtotheinformationavailable.Thenetresultisareduction.intheamountofanalysesandinvestigationsrequiredtoproducedefinitiveconclusionsastoselectionorrejectionofdevelopmentalternatives.Developmentselectionisdeterminedthroughmathematicalprogrammingtechniques(optimization).Theadvantagesofthistechniqueare:-Developmentsareneverfullyrejectedfromthelistbythemodel;-Comparisonsofdevelopmentsarebasedonthesameobjectivefunctionandimposedconstraints.Thedecisionsarebasedonahomogenousandconsistentsetofgeneratedalternatives;-Algorithmsusedtosolvetheobjectivefunctionaremathematicallyprovenandefficient;-Sensitivityanalysesarerelativelysimpletoconduct.Thedisadvantagesofthetechniquearemoreoperationaloreconomicthanphilo-sophicalinnature.Themainprogramislargeandexpensivetorun.However,costscanusuallybereducedbymakingsimplifyingassumptions.TheprogramselectedforSusitnaBasinscreeningusesasimplifiedMixedIntegerProgramming(MIP)Model.TheMIPmodelsareadaptionsofclassicalLinearPro-grammingModelswithintegervariables.GenerallyMIPmodelsoptimize(eitherminimizeormaximize)alinearobjectivefunctionwhichissubjecttoasetofconstraintsorlinearirregularities.InsomecircumstancesMIPmodelscanoptimizenonlinearobjectivefunctionsbutthisisanunusualcondition.Theselectionofthismodelingapproachtoscreenpossibledevelopmentsisbasedonthefollowingobservations:-Manyoftherelationshipsbetweenthemodelvariablesarelinearorcanbemadepiecewiselinear;E-l,IIIII -Mixedintegerprogrammingoffersoneofthefastestalgorithmsforsolvingoptimizationproblems;-StandardsoftwareforMIPisavailable;-Mutuallyexclusivesituationscanbemodelledthroughzero-onevariablesandlogicalconstraints;-Sensitivityanalysesareusuallypartoftheprogram;-TheMIPmodelischeaperthanothertechniques;-Operationalproceduresareuseroriented;and-Thesolvingalgorithmsarereliable.E.2-ModelComponentsThemodelcomponentsconsistofthreebasicsets:variables,constraintsandobjectivefunction.Insomecases,dependinguponstudytype,avariableinonestudywillbeaconstraintinanother.Consequentlycareisusuallyrequiredtoensurethatareasonablesetofvariablesandconstraintsareselected.Theobjectivefunctionislessopentothevagariesofstudytypebutissubjecttoeconomic,social,environmentalandpoliticalpressures.(a)VariablesThevariablesofthemodelaretheunknowns.Generallythevariablescanbedividedintothreegroups:-Statevariableswhichcharacterizethebehaviorofthesystem;-Decisionvariablesthatexpressaresultofachoice;and-Logicalvariablesusedtosetuprelationshipsamongthevariousdecisionvariables.Nophysicaldifferenceexistsbetweenstateanddecisionvariables,andinsome,modelcasesarereversible.Eachvariablecanbecontinuousordiscrete(integer).InthemodeloftheSusitnaBasin,statevariablesare:seasonalreservoir.storagevariation,seasonalenergyyieldandspills.Decisionvariablesare:sites(systemconfiguration),reservoircapacity(damheights),installedcapacity,anddischarges.(b)ConstraintsConstraintsarerelationshipswhichlimitthevalueofavariable,usuallywithinagivenrange.LinearinequalitiesandboundslimitingonevariablearethetwotypesofconstraintusedintheMIPmodel.Linearinequalitiescanalsobereplacedby,orsupplementedwith,equationslinkingseveralvariablestoalimitingcondition.TheconstraintsincludedintheSusitnaBasinmodelare:reservoirwaterbalance,maximumstorage,powerandenergyequations,levelofdevelopment(quantifiedbythetotalinstalledcapacity),convexityoflogicalequa-tions(SectionE4)andlogicalconditionsformutuallyexclusivealterna-tives.E-2 (c)ObjectiveFunctionTheobjectiveoftheSusitnaBasinstudiesasappliedtothisscreeningmodelistominimizecostsofthesystem.E.3-ApplicationoftheScreeningModelTheassumptionsusedandtheapproachtothesitescreeningprocessarediscuss-edinSection8ofthisreport.TheresultsofthesitescreeningprocessdescribedinSection8indicatethattheSusitnaBasindevelopmentplanshouldincorporateacombinationofseveralmajordamsandpowerhouseslocatedatoneormoreofthefollowingsites:-DevilCanyon;-HighDevilCanyon;-Watana;-SusitnaIII;and-Vee.Inaddition,sitesatWatanaandDenaliarealsorecommendedascandidatesforsupplementaryupstreamflowregulation.Themaincriterion(objectivefunction)inselectingtheSusitnaBasindevelop-mentplansiseconomic(seeFigure8.1).Environmentalconsiderationsareincorporatedintotheassessmentoftheplansfinallyselected.Thecomputermodelusedselectstheleastcostbasindevelopmentplanforagiventotalbasinpowerandenergydemand.Intheselectiontheprogramdeter-minestheapproximatedamheightandinstalledcapacityateachsite.Themodelisprovidedwithbasichydrologicdata,damvolume-costcurvesatallthesites,anindicationofwhichsitesaremutuallyexclusiveandatotalpowerdemandrequiredfromthebasin.Itthenperformsatimeperiodbytimeperiodenergysimulationprocessforindividualandgroupsites.Inthisprocess,themodelsystematicallysearchesouttheleastcostsystemofreservoirsandselectsinstalledcapacitiestomeetthespecifiedpowerandenergydemand.E.4-InputDataInputdatatothemodelconsistsofthevariousvariablesandconstraintsre-quiredbythemodeltosolvefortheobjectivefunction.Inputdatatothemodeltakesthefollowingform.(a)StreamflowAsnotedinthediscussionofthemodelcharacteristics,simplifyingassumptionscouldbemadetoreducethecomplexityofthemodelanalysis.Onesuchsimplificationistodividestreamflowintotwoperiods,summerandwinter.ThisassumptionisreasonablefortheSusitnaRiverbecauseofthenatureofstreamflowsintheregion.E-3 FlowsarespecifiedforthesetwoperiodsforthirtyyearsatalldamsitesexceptDevilCanyon,Vee,MaclarenandDenali.StreamflowrecordsusedarehistoricaldatacollectedatthefourgagingstationsintheUpperSusitnaBasin,whichhavebeenextendedwherenecessarytothirtyyearsbycorrelationwiththethirtyyearrecordatGoldCreek.ThesmallerdamsitesatDevilCanyon,Vee,MaclarenandDenali,whichhavelittleornooveryearstoragecapability,utilizeonlytwotypicalyearsofhydrologyasinput.Thesetypicalyearscorrespondtoadryyear(90percentprobabilityofexceedence)andanaverageyear(50percentprobabilityofexceedence).StreamflowrecordsusedasinputtothemodelaregiveninTablesE.1toE.7.(b)SiteCharacteristicsForeachofthesevensites,storagecapacityversuscostcurvesweredevelopedbasedonengineeringlayoutspresentedinSection8.Utilizingtheselayoutsasabasis,thequantitiesforlowerleveldamheightsweredeterminedandusedtoestimatethecostsassociatedwiththeselowerlevels.FiguresE.1toE.3depictthecurvesusedinthemodelruns.Thesecurvesalso incorporatethecostoftheappropriategeneratingequip-mentexceptfortheDenaliandMaclarenreservoirswhicharetreatedsolelyasstoragefacilities.(c)BasinCharacteristicsBasincharacteristicsareinputedtothemodeltorepresentwhichsitesaremutuallyexclusive;thatis,thosesiteswhichcannotbedevelopedwithoutcausingtheeliminationofanothersite.MutuallyexclusivesitesaregiveninFigureE.4.(d)PowerandEnergyUemandThemodelissuppliedwithapowerandenergydemandthatisrepresentativeofthefutureloadrequirementsoftheRailbeltregion.Thetotalgenera-tioncapacityrequiredfromtheriverbasinandanassociatedannualplantfactorhasbeenused.Thecapacityandannualplantfactorareusedtodeterminetheannualenergydemand.ThevaluesusedarediscussedinSec-tionE.5.E.5-ModelRunsandResultsThereviewoftheenergyforecastsgiveninSection5revealsthatbetweentheearliestonlinedateoftheSusitnaProjectin1993andtheendoftheplanningperiodin2010,approximately2210,4210and9620GWhofaddi-tionalenergywouldberequiredforthelow,mediumandhighenergyfore-castsrespectively.Basedontheseenergyprojections,thescreeningmodelwasrunwiththefollowingtotalcapacitiesandenergyvalues:-Run1:-Run2:-Run3:-Run4:400MW-1750GWh800MW-3500GWh1200MW-5250GWh1400MW-6150GWhE-4 Forinitialstudypurposes,theannualplantfactorassociatedwithallthesecombinationswasassumedtobe50percent.TheresultsofthefourscreeningmodelrunsaregiveninTableE.8.Thethreebestsolutions(optimal,firstsuboptimalandsecondsuboptimal)fromaneconomicpointofviewarepresentedonly.Themostimportantconclu-sionsthatcanbedrawnfromtheseresultsareasfollows:-Forenergyrequirementsofupto1750GWh,theHighDevilCanyon,DevilCanyonortheWatanasitesindividuallyprovidethemosteconomicenergy.ThedifferencebetweenthecostsshownonTableE.8arearound10percentwhichissimilartotheaccuracythatcanbeexpectedfromthescreeningmodel;-Forenergyrequirementsofbetween1750and3500GWh,theHighDevilCan-yonsiteisthemosteconomic.DevelopmentsatWatanaandDevilCanyonare20to25percentmorecostly;-Forenergyrequirementsofbetween3bOOand5250GWhthecombinationsofeitherWatanaandDevilCanyonorHighDevilCanyonandVeearethemosteconomic.TheHighDevil/SusitnaIIIcombinationisalsocompetitive.ItscostexceedstheWatana/DevilCanyonoptionby11percentwhichiswithintheaccuracyofthemodel;-ThetotalenergyproductioncapabilityoftheWatana/DevilCanyondevel-opmentisconsiderablylargerthanthatoftheHighDevilCanyon/Veedevelopmentandistheonlyplancapableofmeetingenergydemandsinthe6000GWhrange.OfthesevensitesavailabletothemodelforinclusionintoplansofSusitnaBasindevelopmenttwowererejectedandonlyoneincludedinasecondsuboptimalsolution.TherejectedsitesatMaclarenandDenalidonotsignificantlyimpactthesystems'energycapabilityandarerelativelycostlysowereeliminatedfromtheplans.SusitnaIIIwasrejected,exceptintheonecase,duetohighcapitalcosts.E-5II TABLE E.1 - COMPUTED STREAMFLOW AT DEVIL CANYON OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP -670-.0 697.1 735./ 76l.,5 802·.2,·1-0 4-9-0 r7-1B46B'l6-2+3B-3.'4-'18B-2o-.-6-'-::;'~...-B----­ 1504.6 13218.5 1 9 9 7 8 . 5 21575.9 18530.0 19799.1 943.2 828.2 8 7 8 . 5 4989.5 30014.2 24861.7 19647.2 13441.1 7 15.,t,--"-76-6 .-'1-"1:53b-S-17 T5B-.3--25-B(h-7--1-9-t~-1--9-~7-.v--~B-r4---­ 929.7 729.4 1130.6 15286.0 23188.1 19154.1 24071.6 11579.1 1275.2 1023.6 1 1 0 7 . 4 8390.1 28081.9 26212.8 24959.6 13989.2 893 • 1 -852 ..3 SA 7.3-1 5979.-0 '_':311 37-d--'-z-92 1-2--.,v--'-22-609.8--1649-5.8~-----'-' 1388.9 1105.4 1109.0 12473.6 28415.4 22109.6 19389.2 18029.0 1212.2 1085.7 1 4 3 7 . 4 11849.2 24413.5 21763.1 21219.8 6988.8 1:1 79 .1:'.'S7-7 .9 ..-+1:1 '7-.--9--:1:'-39 *.9-..!21:--:r3-7,7 2-3.:,3-9-&-....r--2-6-5·94·.,~-3-2'9-r6--­ 1340.2 1112.8 1217.8 14802.9 1 4 7 0 9 . 8 21739.3 2?066.1 18929.9 1593.6 1638.9 2405.4 16030.7 27069.3 22880.621164.4 12218.6 1413.4 ·-1-3-2<)'.·3····16·1-3·r4,12141-.z·'4-0-679T7L-249-9-0 ..-6,-r2-24-1.B-'-:l:4·7-6-l-r2-··---" 1387.4 938.4 810.9 17697.6 24094.1 32388.4 22720.5 11777.2 900.2 663.8 696.5 4046.9 47816.4 21926.0 15585.8 8840.0 828.8 ....-~66 .-9,;1.3104.4-t·2·2·~,7-..-1---2·4··1·-i"-O-"",·~.....u-l·-9-5--ri~-1·-9-7.@.¥....·J-..·-1~~~-..·~--_.._·- 1187.4 1 1 8 7 . 4 1619.1 8734.0 30446.3 18536.2 20244.6 10844.3 1268.3 1089.1 1053.7 14435.5 27796.4 25081.2 30293.0 15728.2 1778.7-1778.71791.0 ..14 9.8.2 .•4 ..2 ..9.4·62-.-1 ....2A27.1...-O--.-1.609·0·,·•.5._.-.....S2-25...s- 681.8 769.6 1421.3 10429.9 14950.7 15651.2 8483.6 4795.5 708.7 721.8 1046.6 10721.6 1 7 1 1 8 . 9 21142.2 18652.8 8443.5 943.6 ··-au •8 .,..981.).2-..342i~-.9 .,.3-1-O-3-1 ..,-O---2,2,Q.4-1+6-3-w1S...·9---1~4-+-O----...· 1836.4 1659.8 1565.5 19776.8 31929.8 21716.5 18654.1 11884.2 1128.6 955.0 986.7 7896.4 26392.6 17571.8 19478.1 8726.0 745.9 689.5 949.11-5004y6-16 766.7---1":1-:;"90-.-0 +5-i~-5-t'''dt-''11-3 '7'0.1- 1342.2 1271.9 1 4 5 6 . 7 14036.5 30302.6 26188.0 17031.6 1 5 1 5 4 . 7 876.2 825.2 1261.211305.3 22813.6 18252.6 19297.7 6463.3 ·1509.-8-:I:1:-2-11-i-9 '-3~-.7--z-:i:7-40.-5-1:-8-37-h--Z---i-:t-9+6-.-1-------·..-· 1597.1 11693.4 18416.8 20079.0 15326.5 8080.4 1402.8 13334.0 24052.4 27462.8 19106.7 10172.4 756+9 1583.2 17,)2.0 1649.1 921.7 951.3 905.7 1483.7 -999-.6 1224.2 1318.8 2036.1 1139.8 842.7 1.408.8 87'6.8 165'7.4,.1469 •7"---":1:36-1 .0 1867.9 1525.0 1480.6 1304.1 1203.6 1164.7 131-6.9 1686.2 2212.0 1796.0 1496.0 978.0 925.3- 1278.7 13:::;7.9 1851.2 686.6 575B~2 -2404~7 1342~5 3652.0 1231.2 1 0 3 0 . 8 5221.7 2539.0 1757.5 -7-&1-7-.""6--3'2'32-.-6""1550." 5109.3 1921.3 1387.1 4830.4 2506.8 1868.0 4647.9 --1-7&8.-6--1206.6 5235.3 2773.8 1986.6 7434.5 3590.4 2904.9 ~"""4-<1'2-.B ---1:-9-9-9--T8---1 3 70 • 9 6060.7 2622.7 2 0 1 1 . 5 7170.9 2759.9 2 4 3 6 . 6 ---5-459 ..4-2544-'.1:1978.7 6307.7 2696.0 1896.0 5998.3 2085.4 1387.1 ·5-:,7-44.-0·-.;;L-&4~T'1-1160.8 6496.5 1907.8 1478.4 3844.0 1457.9 1364.9 4585.3.2203 ..5.-1929.7 3576.7 1531.8 836.3 2866.5 1145.7 810.0 4745.2:·30S1 ....$--.2074 •8 5537.0 2912.3 2312.6 4638.6 2154.8 1387.0 3491.4 1462~9 9~7.4 3506.8 1619.4 1 4 8 6 . 5 7003.3 1853.0 1007.9 '-'---315 &2-·.4---'~3-9-1.'::;'-:2 1 A'7 •5 6936.3 3210.8 2371.4 4502.3 2324.3 1549.4 TABLE E.2 -COMPUTED STREAMFLOW AT HIGH DEVIL CANYON OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 'r -,.'.r:..::0 /...1 .;...) 919.6 1,237.3 1448.6 1504.t1 1191"l"9 1198.7 1160.9 1324.2 1570.7 1401.0 1371.3 890.8 824.4 1171.3 1249.5 1761.4 67;:i.9 700.3 930.5 1809.0 1118.5 741.5 1323.8 865.6 662.0 792.5 10345.1 18307.0 21209.6 18669.2 7900.8 691.0 1488.5 13094.0 19862.6 21433.9 18367.1 19593.3 ··S 20·.3---·S7-2 ..·a ·-.4!~·~·g.....·2··_·:J-.9.a·'J·::;·..··a 2 4-6 4 ~.4-~..-4--4 ~:2 1;1 2 r:f-._.... 759.1 1.519.9 17542.3 24932.2 19038.9 19006.6 13736.7 722.1 1115.7 15001.1 22893.5 18981.9 23781.9 11387.6 1012.7"'·1094"+2···-·8-257·.4 ·278-27....9-2-6G20.~24-a4-6-...:;7--·-·13-94-b-.-2--·__···· 839.8 855.4 15738.9 30822.4 28943.6 22335.5 16233.8 1091.8 1096.0 12291.3 28166.1 21938.1 19224.8 17776.0 1-0 7'6 .B-··..--t4-z·3--.-B---:H-&9-9-.·1:---2·~··2·2-9-.--r--z-1·-6-(7;h-5---Z-1-fr3-:i:-+2--~.,....,tllr----- 863.3 1101.3 13602.5 21283.1 23160.5 28225.1 15102.4 1100.7 1206.1 14663.4 14592.6 21562.1 21848.4 18704.1 1614.5-2370.4-··15840.8 26729 ..2-226·3-9·r3---iH<t;'3·0·,7··H?·05-4".2------ 1308.9 1601.0 12077.1 40309.6 24867.8 22055.0 14606.8 952.5 808.2 17507.2 23821.8 32101.0 22584.9 11699.6 6~"j 6·.8 -6-89 .6~-4·0 09·.B---4.]4-24--.·6 ......;2-1 "7 7--9 •7--4-€!i4--b~·..S·_·..S 7-;;5 •6 862.2 1307.9 12163.9 23880.4 25960.8 19599.2 18074.8 1171.3 1596.8 8603.8 30088.6 18347.1 20018.1 10715.0 1073.3 1037-.5 ·14286.3 27551·...6··24B;-;S ..6-..¢9960-T6-·-1SS6-5 ..-0-_·_.. 1761.4 1774.0 14811.3 29163.9 24649.7 15936.3 8141.5 762.9 1408.6 10341.3 14872.3 15587.1 8427.1 4753.0 714rO ··:!:.(}/t·l·.-f!··1-0627.5 -16-90¢.··1 ..-2()~5-....3-··-1-B4-6-3 ..·2 ····8-H6-.:;'·.....·__..__·..·.. 855.0 972.5 3382.6 30759.7 22797.5 30088.2 13521.2 1636.5 1544.9 19475.0 31572.6 21566.0 18563.3 11810.5 948.-5'980.9 7848.126191,.-5'''1-7-47-5.-&-1-936-2·.-1-..·-8-6--7-6T3----- 684.5 943.0 14836.7 16609.0 17645.7 15119.5 11244.4 1253.6 1437.2 13848.9 30015.8 2G969.1 1A880.4 14989.7 814-.-6-'.':1:245,'--2'111'1.'7'.·5 ·2'25-S-9.·ft..rtt·5-il....-t-·-·t~5 ..+"9 ·····&·4€rs·.-'7'..----_.. 1341.1 1485.5 11002.2 35269.1 21579.1 18247.1 11812.7 1462.8 1582.2 11636.8 18:;26.4 19944.6 15174.5 8005.2 ··:t:1-59....-jL·....-1--3-96+1--1:--3-25-7-.-5 z 396h-3-..zn~....-3-TB-9-1-3T3-11;)~8 7 .--(1-- 88~~+2 728.3 760.0 935.1 '735.0 940.5 898.0 1467.·;1·········· 985.3 1213.4 1628.4 913.4 1328.8 1020.9 ·1737.1 1529.1 1371.0 1842.8 1193.3 2379.2 1221 :'3 25-09.7 3194.9 1895.7 2470.7 1772.7 2734.3 1964.4 1566.5 3538",:4 2853.6 17&7.3 1978.4 1350.6 1298.2 2590.2 1984.6 1663.5 2·725.6 2399.8 2177 •7 2521.8 1961.4 1781.2 2681.2 1881.2 1481.2 20~1.9.137;1,.8 9 ~8+0 2623.2 1153.6 920.4 1880.6 1456.5 1261.4 1437.6 1345.5 1337.6 2182.1 1911.8 1832.7 1517.7 829.7 681.2 1135.8 802 ..-0 747.4 3035.3 2044.1 1301.2 2886.5 2284.5 2007.1 2140 •71 1 375 •8 113 1.•2 1454.3 992.2 838.3 1607.9 1469.8 1393.5 183-3.{}997 .4 885.8 2354.8 2111.0 1632.9 3165.9 2340.3 1844.9 229 -4 d·.---H;-3-~h"-6--·12-9-<t."8 4b67.6 ;:i492 .7 4611.8 3456.9 3473.tJ -689,8.2, 3506.4 6845.7 4444.5 .~,-~~8 2,·,9".7 ;5153.7 "7323.4 .. 4344.5 598<;'.6 7081.·9 5394.2 6248.3 ..5~=t34·.0 5665.9 6395.3 3799.4 4540.4 3541.1.:, 5675.8 3624.0 ·51.7-1...9 7419.8 5038.7 4753 r3 4604.6 TABLE E.3 -COMPUTED STREAMFLOW AT WATANA OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 575.2 609.2 3578.8 42841.9 20082.8 14048.2 7524.2 807.3 1232.4 10966.0 21213.0 23235.9 17394.1 16225.6 ·984.7 1338.4..·7-094 .1 889.5 849.7 12535.5 24711.9 21987.3 26104.5 13672.9 1560.4 1576.7 12826.7 25704.0 22082.8 14147.5 7163.6 "686.O'...···1 261.6--"9~13 .?···139'02·.-1.-1:-4&4·3·.5····??-?l1....9······4-£tre.....r-..··..- 624.1 986.4 9536.4 14399.0 18410.1 16263.8 7224.1 717.1 813.7 2857.2 27612.8 21126.4 27446.6 12188.9 1 366 •0 '1305.4 1 5973 •1 2742-9 ..3 ..··1·9820.3 ..1:7509.-;510955 ..:;.· 873.9 914.1 7287.0 23859.3 16351.1 18016.7 8099.7 627.3 871.9 12889.0 14780.6 15971.9 13523.7 9786.2 1041 .-4··1211-.2'·11·6 7·2·~-2·-26-6-&9--..2-.·-234-3<t ..4··4~1:2-6.-6-·13 075.3······... 690.7 1059.8 8938.8 19994.0 17015.3 18393.5 5711.5 1110.8 1203.4 8569.4 31352.8 19707.3 16807.3 10613.1 -·1·25-6.7-1408·.-411·2·3-·1-·,,§··17·27-7ti-..:l:-S3B·:¥;,··2-·;I;~1f!.·,-4-··74-3-2r6---·..... 1101.2 1317.9 12369.3 22904.8 24911.7 16670.7 9096.7 772.7 641.7 569.1 680.1 8655.9 16432.1 19193.4 16913.6 7320.4 "'673";0"········6 rT;13······:r:rOZ·;2···rnr:tt'9·.·g-·!1j;:rt7;·9'-·1-'1"i1:fo··;.o-;,·$·'¢7S.··O-"1"'i4\}~~----· 841.0 735.0 803.9 4216.5 25773.22110.9 17356.3 11571.0 611.7 670.7 1382.0 15037.2 21469.8 17355.3 16681.6 11513.5 803.1638 .1~942.6 11·69-6.8 1050.5 886.1 940.8 6718.1 24881.4 23787.9 23537.0 13447.8 754.8 694.4 718.3 12953.3 27171.8 25831.3 19153.4 13194.4 1189.0 ·····935.-0 915'.1 -l·"4B-4·f"·rt---~--_· 1041.7 973.5 1265.4 9957.8 22097.8 19752.7 18843.4 5978.7 949.0 694.0 885.7 10140.6 18329.6 20493.1 23940.4 12466.9 -1138.9 961.11069.9'130440'2 1 .:1.-1-*&5..·6----_.- 1304.8 1331.0 1965.0 13637.9.22784.1 19839.8 19480.2 10146.2 1257.4 1176.8 1457.4 1j333.5 36017.1 23443.7 19887.1 12746.2 118+.7 ·..883r6 ..····7176.·b··j ,::;29·9·.. 781.6 984.7 1031.3 1560.4 607.5 602.1 777.4 1491.4 1000.2 689.S' ·11·lO.3 743.2 1202.9 ·1·267.7 1055.4 815.1 '808';'0 1274.5 8:1.8.9 1087~8 1388.3 816.9 1373.0 1480.6 1081.0 1400.4 1779.9 1608.9 -1308.·9 852.0 863.0 106{).4 1:1.02.2 16;.17.6 619.2 636.2 1097.1 1670.9 1031.5 786.4 1215 ..8 757.8 1348.7 1577.9 1136.8 1168.9 "906;2 1501.0 1281.2 1183.8 1549.5 1038.6 1"707."0 2258.5 1115.1 1672 ..3 1973.2 1760.4 ···1708.9 1194.7 1070.3 1203.6 1121.6 1/'04.2 753..9 709.3 1687.4 1957.4 1246,5 931.6 1276.7 876.2 1687.5 1979 ..7 1312.6 2368.2 15650·3 1202.2 H'34.3 1354.·9 1020.9 2496.4 2587.0· 1977.9 1354.7 ·1474.4 1601.1 1926.7 2645.3 1944.9 2263.4 ·25-08.,9 1789.1 :305bt~':; 5·2·2,·-1,.2 3269.8 3088.8 5679.1 2973.5 5793.f;' 3773.9 4019.0 ··3·135.0·· 2403.1 3768.0 ·4979.1 4301.2 4719.9 2083.6 ···········329lj~T·.rl0T~"J' 4592.9 2170.1 6285.7 2756.8 4218 ..9 1599'.6 3859.2 2051.1 4102.3 1588.1 4208".02.2'76 .6- 6034.9 2935.9 3668.0 1729.5 5165.5 2213.5 6049.3 2327.8 4637.6 ··5~{).1 5187.1 4759.4 TABLE E.4 - COMPUTED STREAMFLOW AT SUSITNA 3 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP _·_··--~4:J.+~·7--~-9-4-.-5·---9-0A··.3 2761.4 918.5 716.3 3634.8 1607.9 1110.2 ·--44(}8·..S---2-<t-3-1-.·6----·EF71 .0 2862.1 1109.4 874.1 2379.1 1356.7 1064.1 -··-·-·¥r7·-0·r9-·~8-2i -;-7-82--.5 2642.6 1519.0 1280.8 3902.2 1938.5 1 2 7 3 . 5 "·-254ft.4 ·F3-17··.-5-·..·725 .3 3801.4 1590.0 1155.3 4340.1 1669.3 1267.0 _·_·······_-~SS·....4..·_·~-·-142+·..7 4420.9 2223.8 1423.8 3951.0 1337.6 901.4 ·:;;259·~·O 19A:-b .....2 932.:i 3277.9 1043.5 784.9 2394.9 812.5 750.9 :;;±~;;·5T9 ····-1..a-24·..2·····-1-360 ..6 2462.1 1085.5 628.5 1696.9 830.8 555.8 22·i'9 r1 1604.-3--1097.2 4128.9 2091.3 1416.1 3787.1 1708.5 1032.4 23-93.-7 .11B9-.7---831.4 2451.8 1253.4 957.1 3661.3 1217.2 675.6 -2091.3 ·1218.1 986.6 4053.2 1783.5 1 3 8 2 . 8 2664.0 1366.9 951.8 1:,07 ..-5·..·•··#S.-3··..---4-4~--···-4J;'4-M}·_···-5 B /:,0 .:1.:I.;3;;:2 B • 9 1 5B 5/:,•4 1 4 ~.;'/:,;3 5 9 • 8 659.1 529.0 502.1 993.8 9259.4 16292.1 17060.0 13351.1 13253.3 955.6 685.2 592.9 690.2 3038.5 19311.4 17919.1 13865.3 8721.4 543·.5··.··-4-G7l..-b--·---5-24-rS---1-1-;"3.8 ..1-()-&9-<1-.-t--1-·~-9--f~4-4S-CrB-r7 12 a 3-3"":3-··-~·....,""'7-'--- 880.0 610.2 499.4 656.3 6227.6 13821.2 13676.0 14857.0 5487.7 990.8 708.1 676.6 6 8 6 . 9 4170.3 20004.4 20092.8 21369.2 12622.8 .-6&7.1-----5-44-dt---·-4-53-TB---·-4·9-!-.-4-·...8 3-04 2 • 6 2-H:29 •'"2 0 6 '7 9 • 8 13 e 8 6 •5·--€1-16 3-•5 1052.6 884.3 675.4 6 9 5 . 4 6675.3 20489.7 16656.5 14161.2 9983.4 1006.0 781.8 802.6 1003.3 7075.7 18569.2 16689.2 15222.2 4439.4 721·.5 -5 98 ··.··2-·_...4-1·3T8-·..·-52el8---4-4·H)-.5··-l-3-4-4-h~re.·~-e-.+·~€H~+.=r----_· 964.9 832.2 730.1 844.6 10364.3 10983.7 16103.2 15143.3 11751.6 1121.5 864.9 8 6 1 . 8 1294.0 9991.8 16254.2 15206.1 16913.9 6988.2 -1·3·2·3··.-8-_·..~·1··0 1-9·..-8-..-9-r;.a.....2~--1-2-:l.-9~.8 1010:2.6 :2 8 9 12 •2 2100 6 ..4 1 (:,2 9 9 ..G .-9 (:,6 6-..(, 1023.8 875.7 769.5 724.4 11644.6 15435.6 23249.8 18407.0 9311.1 660.0 6 0 1 . 0 440.2 476.1·2865.4 35261.7 17274.1 11705.2 5519.1 767 .9..---b8 7.-1-....7·1-6-..·-6---11 (j·:;.t·.-4-··-89·8-3..f!·-1-b-7-9 7-.9.;1 872 S •B-+~l'2"+3-1-6-S-l~--­ 727.7 675.7 675.7 910.6 4595.2 19072.3 1 2 5 2 2 . 6 13042.4 6730.0 712.5 670.1 585.3 538.9 9690.7 20011.7 17272.9 19721.9 1 0 5 4 1 . 0 1 26-1.-7..122-7·..7-..--;t22..7.·-7··--12·:;O ..2--·..9~4-h-7--·-1-9-9--7-h·2 1 7 a:;"+..-1 111 U .....i~-····5 5 44.-9---· 516.6 494.4 5~8.6 1018.3 7612.7 12455.5 1 3 6 1 2 . 6 6687.4 3444.0 452.3 4 3 9 . 5 4 7 5 . 4 894.6 7730.5 10254.4 14246.9 12623.4 5365.9 759.2·524 •:l:....48-9.0 ...-·-5G{h9·:l:9-8.;'-.·5-"2·2-4-o-+.·1--4B';;'6--G,-S-·~7L4-.-4-·- - ' r 9 - B 3 - r B - · _ - 1114.4 965.8 918.3 9 0 9 . 0 10177.0 20571.5 16930.8 15765.3 9540.9 866.4 8 0 4 . 5 750.4 803.5 6358.4 19999.0 14491.0 1 5 7 8 9 . 9 7145.3 70&.6 .60A .6 ··-5-32".""6 '-........7 54·•-3 96-6-5.-2,1--'./;":;'-54-.·-3-,1 3 :2 0 1.·5--~8-2-.-5-'''':;-3-7'2-r7----· 921.8 757.0 690.1 837.3 8069.4 21183.0 19228.4 1 2 2 2 3 . 6 9906.6 546.0 5 4 0 . 7 485.6 733.1 5332.7 15697.4 15129.9 17015.6 4566.0 878 •1796-•2 729.-6-6.-6 4542.7 2A-8+··0-...:;Z ..-1-~·..2·-1-442·4-~·3----8·6~7··.-7..·..·_·- 1135.9 875.5 915.4 1120.8 10527.7 15540.5 15804.2 10494.9 5688.4 881.8 829.4 1004.4 1 1 8 8 . 5 10899.3 21155.9 21024.3 12958.6 7457.5 TABLE E.5 -COMPUTED STREAMFLOW AT VEE 3005.9 1553.7 882.3 2716.6 902.8 700.5 ~55S.~4~~4~01077..6 4252.1 1971.2 836.8 2749.0 1068.5 848.3 ~2-255.'8i29Eh 8 ---1023.7 3201.6 1257.2 761.2 2512.1 1455.9 1245.3 3724.'7j .'1855.4 1191.4 2455.1 1283.2 692.8 3687.7 1538.0 1112.2 ,·-4-1~97.::;·--46-iA-.-4--1208.2 3281.0 1800.0 1400.0 4326.0 2200.0 1400.0 3848.0 1300rO B77.0 3134.0 1911.0 921.0 3116.0 1000.0 750.0 -2322 ..0 ·780.0 .-.-.-··72<).0 3084.0 1490.0 1332.0 2406.0 1063.0 618.0 :l638,.{J 815.0 543.0 2155.0 1530.0 1048.0 4058.0 2050.0 1371.0 --37-44 ..3 -1686.0 -1-014.6 2338.5 1176.0 823.0 2398.7 1235.0 930.5 3493.1 ·U.8·5.2 658 •9 2017.8 1159.1 928.2 3908.1 1711.7 1333.1 2571·.,5 1314j.7 921.7 SEPAUGJULJUNMAYAPRMAR 402.6 478.5 5627.1 13070.3 15578.3 13765.5 6279.8 492.3 968.1 9060.2 16106.6 16832.8 13090.5 12924.0 581.1 ·6-8(1.7 2940r3 ·13574 512.3 1134.8 10545.2 15261.4 14336.5 12512.6 7527.0 487.8 632.4 5771.8 13349.9 13400.4 14393.4 5181.2 .65-9'.-1;---,,''6 65.'7 '~i·Qr;r~,~··fr·······'4-.c;'C:;'<:;~~·4+··4-·~i~-i=i-A-·,...Q-···e;q-+t::l-~,,-t'·--1~~J::;·'::~·,.--A-----_.. 433.8 472.5 7958.4 20625.9 20250.5 13447.6 7744.3 653.8 674.6 6383.6 20090.9 16382.1 13898.2 9578.6 788.4 981,-'5 ··,-o835.'5-i:B275--+"1---1;--t;>Y3'3'".9'-1 a <;>''':>A "It ··-"t\--~-H-·_-+·-'-'--"·-· 390.3 499.1 3933.0 13033.6 13710.3 16257.6 7741.2 710.8 825.8 10141.0 10796.2 15819.6 14795.0 11390.4 .89.2l7 ..·-12 :3 8.1:·········9 68 8,,·<)---1-~r7-1.~-+4~(}--1-tr74Hh·.e-'·-6-7-£l:-\5..~-"---;..­ 940.0 1200.0 10000.0 28320.1 20890.0 16000.0 9410.0 760.0 720.0 11340.0 15000.0 22790.0 18190.0 9187.0 429.0 465.0 2806.034630.-(j"..1;4)4(h·0..--l'Hijl0.~..-~;352-.G------ 709.0 1097.0 8818.0 16430.0 18350.0 li440.0 12910.0 650.0 875.0 4387.0 18500.0 12220.0 12680.0 6523.0 -·-56-0;O·,···513rtJ-·9 45 2.-0--4.-9-6-2-0--M1-'4--6-8~-..-1-9-H-o.4--l:-O---2B(j-rO-..----- 1200.0 1223.0 9268.0 19500.0 17480.0 10940.0 5410.0 548.0 998.0 7471.0 12330.0 13510.0 6597.0 3376.0 46-3.0 ,·887.0 ·758().-<J9-9<J-9·.0----1-"39·0-(hO--i-2-3-2-0-..0 -'5-2-1-:l:T~)-'----' 470.0 529.0 1915.0 21970.0 18130.0 22710.0 9800.0 881.0 876.0 9694.0 20000.0 16690.0 15620.0 9423.0 "7·40.1..'7-94.36281.-0 ·-19677..-3-....1-43-3&.0·-1"5-6-04·..-3-~l-065.-H-..-···.... 524.7 744.5 9396.5 11502.1 12970.6 10662.4 7171.6 660.8 806.1 7769.2 20724.2 18878.2 11981.7 9642.5 468 •-5 ..-.727.5 5032 ..215339 .-4....14~7.2 ..·S....;l·4·9·(),O",-B '44-7-0-.5·-,·,-- 697.8 697.7 4207.1 243~0.5 16351.0 14225.7 8462.2 887.0 1096.8 10469.1 15395.8 15589.1 10251.8 5568.0 ,··99-.{,·.~117+...'l .,1:077'{".-8--..2-1·'()14-.·2·-,·24-700·.-~·..-1..2«-9....~····7~.9 JAN FEB 590.2 486.4 646.7 517.0 929.0 672,2 520.6 390.6 862.7 594.1 957.7 679-.6'- 643.8 526.4 1025.9 858.9 966.5 760.1 691.5 569.0 928.6 806.6 1066.6 828.2' 1300.0 1000.0 1000.0 830.0 644.0 586.0 760.0 680.0 700.0 650.0 680.0 640.0 1232.0 12'00.0 508.0 485.0 437.0 426.0 731.0 503.0 1068.0 9::2 +0 832.6 788.2 693.5 597.5 897.3 727.6 528.4 523.8 8~8.9 ?62+3 1099.1 842.8 8.€>-O.'{'-8l0.,.€>- DECNOVOCT TABLE E.6 -COMPUTED STREAMFLOW AT MACLAREN ._._----------------_._._-------------------------_._-------_._---_._---_. 2482t~j 2256.2 1778.3 1408.2 1961.5 1932.0 ::~3:;~7.0 1589.4 2817.8 2144.1 :;1472.0 2179.0 2182.7 1862.1 .. 1891.8 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1851.5 930.0 557.2 340.3 308.0 229.9 296.0 3345.8 8595.6 11824.2 9947.8 3932.9 15 :;z 9 •9 52 9 -.-7~0 8-.-8 --34 8-.--9--2-7-9-.--7--27-6-.-2--5 66--r3-54-20-.-9-1-06 05-.6-1-26-3-1-.-5-98 9 8-.-4-817-4-.-3:---- 2043.6 845.0 583.8 544.9 436.3 384.7 441.3 2224.2 12442.8 13272.1 10301.1 5261.9 2392.9 1158.0 490.4 326.4 240.8 288.2 705.7 7047.4 11176.5 11218.7 9206.1 4547.9 620 .8--483--.-7---532-.-7--363-.-1--307·-.-0----·368-.5--361·6 .-3--8975 .5-10546-·.-4-10528.9-3368-.0------ 818.3 562.2 532.8 370.2 379.6 390.1 2753.9 13038.6 13381.9 15813.8 8225.5 709.6 454.1 416.2 285.3 263.4 289.2 6372.9 18316.8 16750.4 13544.8 6560.6 104 o.5--783-.-2--·5-7-6-.-9---4 84-.-6~5-9•4 436-.--9--4·7-08-.-5-1-55·9·0-.-9-1-34 06-.-0-1-154 0-.-4-6402-.-9'---- 1144.3 675.6 539.7'411.7 406.7 541.0 3596.5 12617.6 12274.8 10132.9 2922.4 773.2 394.3 364.6 290.4 191.3 238.7 2704.8 10668.2 11497.9 11475.:1 4747.3 1093.8----805.5--··_·65-1-·.-9···---529.3--46-2-.·-O--5()~-;..·6---6262.-8 --762 1-.9-1-1'94 7-.-9-10863.7--7637.-0-------· 1069.4 794.1 646.6 510.0 513.4 768.1 5845.7 10400.8 10970.3 11305.8 4423.9 1160.5 851.8 717.6 566.0 528.9 674.7 5544.5 17338.()14797.4 ~2262.2 6120.5 1235·.·0--7-7-7--.-6--5-7-1-..8--496-.-0--44()-"';'~--428-.-8-672·2-.-3-1-0-296-•.:;-1-5-7-7-2-.-4-1-3633.-4-6196-.-1---- 723.3 481.9 356.2 331.3 246.9 273.7 1723.4 21497.0 11636.6 8679.0 3799.5 1220.7 554.4 451.7 405.9 422.9 653.3 5189.9 9701.9 11729.8 9057.0 9509.7. 600.3 ..·----458.8---420.-2--393.-1--393·.-1--··..:,35.·3-2812-....2-1·1847 .-9---9974v3--9112-.4-4625-.·6 .--- 637.5 504.2 485.6 411.5 430.0 362.0 6395.0 13647.0 13610.8 137H4.5 6087.5 926.3 771.4 674.9 694.7 708.5 648.9 4428.6 12364.3 14259.6 10303.3 3572.5 1431 • 9 ,"-629 ..6---3 63...3---3 0 0+7--2 88 ....0---31-7.....-9--:i 58 .....9-·-4214....6-9-94 {).....-9-1-U·8 8.....9-5 06 7-.-9--2 711 ......9 1.2 7 4 •8 635 •7 426 •5 33 8 •8 308 •9 308 • 8 5 62 • 7 45 :I.3 •7 7 11 :~• 4 1 0790 •3 883"4 •6 33 46 •7 1226.0 881.9 607.2 410.7 287.2 270.1 304.0 1180.7 14049.7 13721.9 15681.0 6081.6 2 :~3 4.2 -.-1:1.52 ..4·--·-80:-i..-l·--651.7-······-~.)70·..8--~i41...-3 ...--5~~0.0 ---6139·.-0--1-2326...-9 ..·1312-7 .-0--1-1648.1--5628 ..-7-------- 1987.2 907.7 555.7 467.4 431.8 404.9 428.1 3289.5 11719.7 10915.7 10844.3 4427.3 1503.4 768.3 562.:1.474.5 411.1 359.3 469.0 54H2.0 8156.0 11015.7 9879.9 6189.7 2248.1 914.-1--616-..-7--556-.-2----426...-3-39:/-.-7--460-.-0-4269-.-4-1-29-10 .·5-ltiOl-3-..--6-9305·.-6--..6175 .-7---- 2377.3 722.6 379.2 290.6 280.1 252.4 382.3 3189.5 9971.8 11309.9 13006.1 2958.2 1376.1 763.9 587.2 511.8 464.1 431.3 439.8 2660.2 15150.2 12730.3 11915.6 5747.0 2J:~:;!.1·1106 .·6---·822-.6..----6'70·.·;;>--532.......9-·-52.hO--620.-7-5650...-9--96()2.5-1-1822.·7---9333.-7-·...,4456.8------ 1597.1 830.1 573.6 519.4 478.5 543.3 648.0 6216.9 13381.5 14307.2 10667.2 5717.0 TABLE E.7 -COMPUTED STREAMFLOW AT DENALI OCT NOV DEC JAN FEB MAR APR MAYJUN JUL AUG SEP 1493.~618.9 398.2 219.4 220.1 149.6 218.8 2531.9 6232.7 10078.0 8015.0 2478.8 --899.0 ----3-10-.-2--250-.8--1-7-3--.-1--14 7-.--9--1-5h-8--363-.-7-3-4 56-j.-3---7J 89-.-2-1-0352.8--8506.-8-587 8 ..0----- 1216.4 1600.3 1485.8 1247.9 1297.5 2000.2 1963.6 1299.5 2016.2 2:Dl.2 169:-L2 1445.7 1323.0 1951.0 1545.6 18;:;0.3 191:;'.1 -916.6 1229.4 :1007.3 LH2.7 832.5 1089.4 2340.:1 2188.6 11 78.0 1708.4 1222.3 488.0 338.6 359.1 309.3 282.9 298.1 2065.4 9767.3 11392.7 8965.7 3758.5 780.5 362.2 269.1 193.9 166.9,456.8 5754.4 9952.4 9773.4 7960.8 3494.4 --442.3---309 ..4----35 h-6---2~.i-1-.-6----215-.9------262-.-5--3-7-57.-7---7509.-7-9467-.0--9416-.-6-----:H 89.B------- 680.9 371.8 341.6 248.0 237.1 264.7 2669.5 9680.5 9760.9 12473.6 5239.0 396.4 305.7 296.6 172.0 212.7 224.6 6666.0 18527.2 15779.2 15313.5 7290.9 ---972-.-3---573.-3--3-4-2-.-6--301-.-4--2-2-h-~~38-.-7-45-7-7-.--1-13750-.-6-1-22-30-.-0-10785-.-2--5580-.-9----­ 931.1 605.1 371.8 233.7 175.0 294.4 2090.9 9503.0 10136.3 7701.8 2374.6 522.6 295.5 234.7 193.9 131.9 -157.9 3626.7 10464.8 9754.31016~.1 3902.4 960.7------74 :1:-.-4 --------584.-:2----41 9.7---349..4---33/-.-6--421.-1:.-8 ---5961.3---10134-.5 ----9255.6 6212.-3----- 872.0 710.3 543.0 412.6 4:52.1 631.0 4132.8 8514.2 9569.8 8079.2 3711.7 817.7 547.1 371.8 316.5 290.4 356.5 2593.3 11374.3 10978.9 10609.2 4640.4 ---601-.8--40 t-.8---~~·H-.8--329 .~_)------236-.-7--2';'~6-.-8--4429-.-6-8446.0-.1-;2276-.-3-11048.4---4428-.-3----- 435.4 279.4 201.8 198.1 153.5 172.8 1139.7 14070.3 8481.2 7306.3 3278.5 837.9 323.4 250.6 227.5 237.2 360.2 3102.3 6068.4 8208.0 6939.0 7940.3 -468.0 ---37 4 ;8---·-317-.-1.--·---299.~i ---·-299-.::=i----41_-7-.:J-243~h5·---9060.8---9455.9-----7832.0·--3999.-7----------- 655.9 461.4 465.1 356.1 430.2 348.6 5020.6 10672.6 12672.4 11778.1 3946.0 634.8 460.8 371.0 422.1 446.4 322.7 1850.2 8846.9 13207.8 10778.2 2713.1 390.8 ---21.2-.--4--1-78..-0--:1-7 6·.-4--1-B6-.-0--30-7-...3-23l5.-6--863l-.0-984-1-.·3---4-268-.-1--..2475.7--- 562.2 388.4 324.2 273.3 240.9 348.5 2791.4 6347.3 9794.3 7388.0 2544.2 682.2 466.0 278.8 206.5 193.4 219.6 909.0 9775.9 11300.5 11807.6 3997.9 637.6-·-554.-~~---5180'~~--4 76.2---430 ...-"----397.6--53.34.0·---8769.8-1.·1-380.2---9225.5 --3233 .::'i ---- 409.8 279.9 231.2 227.0 192.8 188.6 1341.0 6983.8 8944.8 7984.9 2752.3 515.1 398.3 337.6 298.5 265.5 299.9 3578.9 6616.3 10438.9 10142.3 6229.0 -744.1-----483 ..-9------3 9-4.7---_:~1.3 ..-/--3-1-3--.-t--3-:W-.--4-27-9-9-...9-8812-.-6--1-3-462-..8-8 22 9-.6---4591 .:1.---- 498.6 233.6 180.2 162.2 156.0 221.8 2965.9 7322.2 9165.0 10523.6 2190.8 695.1 556.6 417.5 370.9 353.7 396.3 2794.4 10339.8 11007.4 10947.2 4346.2 9:~9.4------63_1..-2----490 "3---426-.3·--355.-9----355 ...6-22,,,)7.6 ---5809.1-9823.9--~-9583.1----4087.0---- 649.1 428.2 345.1 301.7 234.2 291.7 3264.3 8213.0 10755.5 10373.0 5039.7 TABLE E.8 -RESULTS OF SCREENING MODEL .... Total Demand Max.Inst.Total Max.Inst.Total Max.Inst. Energy Site Water Cap.Cost Site Water Cap.Cost 6 Site Water Cap. Run MW GWh Names Level MW $x 10 6 Names Level MW $,x 10 Names Level MW $ 400 1750 High 15BO 400 BB5 Devil 1450 400 970 Wat.ana 1950 400 9BO Devil Canyon Canyon 2 BOO 3500 High 1750 BOO 1500 Watana 1900 450 1130 Watana 2200 800 1B60 Devil Canyon Devil Canyon 1250 350 710 TOTAL BOO 1840 3 1200 5250 Watana 2110 700 1690 High 1750 BOO 1500 High 1750 B20 1500 Devil Devil Canyon Canyon Devil 1350 500 800 Vee 2350 400 1060 Susitna 2300 3BO 1260 Canyon III TOTAL 1200 2490 TOTAL 1200 2560 TOTAL 1200 2760 4 1400 6150 Watana 2150 740 1770 N 0 SOL UTI 0 N N 0 SOL UTI 0 N Devil 1450 660 1000 Canyon LEGEND•COSTDEVELOPEDDIRECTLYFROMENGINEERINGLAYOUTSCOSTBASEDONADJUSTMENTSTOoVALUESDETERMINEDFROMLAYOUTS10001000800~IDQ600..-~400u20000DEVILCANYON15001000.....IDO><-I-(f)0u500150050004000100020003000RESERVOIRSTORAGE(103x AF)HIGHDEVILCANYONO'-----£-----£-----"'-----"-----~_..oDAMSITECOSTVSRESERVOIRSTORAGECURVESFIGUREE.I 2400LEGEND•COSTDEVELOPEDDIRECTLYFROMENGINEERINGLAYOUTSCOSTBASEDONADJUSTMENTSTOoVALUESDETERMINEDFROMLAYOUTS1390186015001000U)Q)(-I-en8500OL-_--l__-L..__.L.-_--l__..J-__.L.-_--l__......o20004000600080001000012000RESERVOIRSTORAGE(103xAF)WATANA4002000..l-S4000100020003000RESERVOIRSTORAGE(103xAF)SUSITNAIIIo'--.......L.-.L.-......-----l..oDAMSITECOSTVSRESERVOIRSTORAGECURVESFIGUREE.2 0'-_-.1.__""""-__"'--_......__........__......__..........o200400600800100012001400RESERVOIRSTORAGE(103xAF)MACLAREN1000800~600)(-l-I/)8400200800600~)(-~400l-I/)ou2002004006008001000RESERVOIRSTORAGE(103xAF)VEE~500~1060LEGEND•COSTDEVELOPEDDIRECTLYFROMENGINEERINGLAYOUTSCOSTBASEDONADJUSTMENTSTOoVALUESDETERMINEDFROMLAYOUTS800l-4008200_-~4401000200030004000RESERVOIRSTORAGE(I03xAF)DENALI5000DAMSITECOSTVSRESERVOIRSTORAGECURVESFIGUREEJiiJ TYONEBUTTE CREEKMACLARENIDENALI BUTTE CREEK DENALI MACLAREN WATA~A I SUSITNAml VEE VEE DEVIL CREEK SUSITNA m WATANA DAM IN COLUMN IS MUTUALLY EXCLUSIVE IF FULL SUPPLY LEVEL OF DAM IN ROW EXCEEDS THIS VALUE-FT. VALUE IN BRACKET REFERS TO APPROXIMATE DAM HEIGHT. LEGEND DEVIL CREEK HIGH DEVIL CANYON DEVI L CANYON OLSON COMPATIBLE ALTERNATIVES MUTUALLY EXCLUSIVE ALTERNATIVES D GOLD CREEK MUTUALLY EXCLUSIVE DEVELOPMENT ALTERNATIVES FIGURE E.411111 F.1-IntroductionAPPENDIXF -SINGLEANDMULTI-RESERVOIRHYDROPOWERSIMULATIONSTUDIESTheaveragemonthlyinflowinanymonthisutilizedasfollowsinorderofpriority:energyunderconstantheadcondi-isusedtosupplementtheinflowandifavailableinflowexceedspowerreplenishedbyanysurplusinflow.InflowF-l-Powerhouseflowtomeetdemand;-Fillreservoir;-Generatesecondaryenergy;and-Spill.Ifinflowisinadequatetomeetdemandtions,thenstoragefromthereservoirthereservoirisdrawndown.Conversedemandneeds,thereservoirstorageisThesimulationmodelisdrivenbyanenergydemandcurveandwillattempttomeetthisdemandineachmonth.Adeficitisnotedwhenthedemandisnotmetandafailureofthesystemisrecorded.Ifthenumberoffailuresinthestudyperiodisexcessive,theenergydemandistoohighforthesystemandanothersimulationmustbemadewithalowerenergydemand.Thisprocessisrepeateduntildeficitsarerecordedinnoneorinonlyoneyearofthesimulation.ThereservoirsimulationmodelsdeterminetheenergyyieldfromtheSusitnadevelopmentsgivenusinginflowdataforthethirtyyearperiodfrom1949to1979,theinstalledcapacityateachhydroplantandaspecifiedannualenergy.demandpatternandplantfactor.ThetotalenergysuppliedbySusitnawasassumedtobeafractionoftheforecastelectricalsystemdemandfortheRail-beltregionasdiscussedinSection5.Themonthlydistributionofthegener-atedenergyisassumedtobeequaltothemonthlypeakloadmultipliedbytheloadfactorinthatmonth.Environmentalconstraintsincorporatedintothemodelincludeamaximumseasonalreservoirlevelfluctuation,amaximumdailyreservoirfluctuationandaminimumdownstreamflowrequirement.Theseconstraintsarepreliminaryatthisstageandareonlyusedtoprovideconsistencybetweenenergyestimatesattherespectivedamsites.TheeconomiccomparisonsofvariousSusitnaBasindamsitesdescribedinSection8,bothindividuallyandincombination,wereaccomplishedtoalargeextentthroughsimulationofenergyavailabilityfromagivendevelopment.ThepurposeofthisAppendixistodescribethetwocomputermodelswhichwereusedtosimulateenergyyieldsaccordingtothestorageandhydrologyavailableatthevariousdamsites.(b)UtilizationofMonthF.2-SingleReservoirModel(a)EnergyOemand (c)ActionsatReservoirBoundaryCondition~Underboundaryconditionsofeitherminimumreservoirlevelormaximumreservoirlevel,thefollowingactionsaretaken:(i)MinimumReservoirLevelTurbinedischargeisassumedequaltoinflowplusthestorageavail-abletoreducethereservoirtotheminimumlevelattheendofthemonth.Ifdischargeisinadequatetomeettheenergydemand,afail-ureisrecorded.(ii)MaximumReservoirLevelWhenthereservoirisfull,thetotalcapacityoftheplantistheor-eticallyavailableiftheinflowisadequate.Consequently,thedis-chargeissetequaltotheinflowexceptwhentheinflowexceedstheinstalledcapacity.Inthiscase,thedischargeequalstheplantcapacityandthesurpluswaterisspilled.Energygeneratedabovedemandisdesignatedassecondaryenergy.(d)SimulationProcedure(i)MonthlySimulationThemodelcomputesthedischargethatwillgivetheenergydemandfortheheadavailable.Ifreservoirstorageisdepletedorreplenished,aniterativeprocessisusedtodeterminethecombinationdischargeflowandheadnecessarytomeetdemand.Forthesepreliminarystudiesithasbeenassumedthatiftheenergy.'generatediswithin5percentofenergydemandforsinglereservoirand1percentformulti-reservoir,theresulthasconvergedsufficiently.Asnotedearlier,adeficitisnotedwhenenergygenerateddoesnotmeetenergydemand.Becauseofthenatureofthissystem,adeficitcanonlyoccurwhenthereservoirisdrawndowntothespecifiedmin-imumlevel.However,energyisgeneratedsincethepowerhouseflowisassumedequaltoinflow,givingnochangeinreservoirlevel.(ii)DailySimulationThemonthlysimulationhassuperimposedonitadailyrequirementduetopeakingoperation.Theoperationhasbeendividedintobaseloadcapacity,peakingcapacityandsecondarycapacity.Thepeakingcapa-cityhasbeenassumedtobeneededfor10hours.Baseloadcapacityandpeakingcapacityaredeterminedsothatthesumofeachdailygenerationforanymonthequalstheenergydeterminedinthemonthlysimulation.Ineffect,monthlypeakingcapacityisequaltotheratioofmonthlypeaktoannualpeakgiveninFigureF.lmultipliedbythenominalinstalledcapacity.Baseloadcapacityisvariableanddeterminedtoproducethenecessaryenergytomakethedailyoperationconsistentwithmonthlyenergyvalues.SecondarycapacityF-2 isonlyusedwhenthereservoirisfullandwouldhavetospill.Secondaryenergyisassumedtobegeneratedfor24hoursbythedif-ferenceininstalledcapacityandthesumofbaseloadandpeakingcapacities.Secondaryenergycanalsobeproducedduringtheoffpeakperiodbythecapacitydifferencebetweeninstalledcapacityandbaseloadcapacity.Alowerlimitonbaseloadpowerhouseflowistheconstraintofmini-mumdownstreamflowwhichmustalwaysbemetexceptwhennecessarytoviolatetheminimumreservoirlevelboundary.Ifbaseloadpowerhouseflowshavetobesetequaltodownstreamflowrequirements,thenpeakingperiodpowerhouseflowsmustbereducedtomaintainthemonthlyenergybalance.Apeakingcapacitydeficitisthereforepro-ducedandthiseventisrecordedandprinted.F.3-Multi-ReservoirSimulationThemulti-reservoirsimulationfollowsthesameoperatingrulesasthesinglereservoirprogramexceptthattheenergydemandinaparticularmonth;sallo-catedtoeachhydropowerplantaccordingtothereservoirstatusinthatmonth.Thisallocationrulepreventsthestorageofwaterinonereservoirwhenanotherreservoirisbeingdrawndown.Theallocationoftheenergydemandbetweenres-ervoirsisgivenby:H..E..=E.lJlJJT.lJwhere:E·=theenergydemandinmonthJJE·.=thefractionoftheenergydemandinmonthjallocatedtolJthehydropowerplant;H·.=thenetheadinmonthjofthehydropowerplantilJHij=thetotalheadofthecascadeinmonthjAfterthisallocation,thesinglereservoiroperatingrulesareappliedforeveryhydropowerplant.Thereservoirischeckedforitsfinalstatussolvingthesamenonlinearsystemofinequalitiesiterativelyforeverymonthofthesimulationperiod.F.4-AnnualDemandFactorAnannualdemandfactorisinitiallyspecifiedtoenableanestimateofthemonthlyenergydemandtobemadeforagiveninstalledcapacityandmonthlypeaktoannualpeakratios.Theintentionofthisdemandfactoristoalloweasyadjustmenttotheenergydemandcurvewhichdrivesthesimulationprogram.F-3 Adjustmentofthespecifiedinstalledcapacitywouldalsoadjusttheenergydemandcurveifthedemandfactorwasheldconstant.Consequently,thedemandfactorusedcoupledwithinstalledcapacitymustbeconsideredonlyasameansofdeterminingtheenergydemandthatcanbesuppliedbyagivenhydropowersystem.Environmentalconstraintsandhydrology(shortagesandsurpluses)leadtoanactualplantfactorwhichisslightlydifferentthanthenominaldemandfactorspecifiedtodeterminedemand.F.5-InputtoSimulationModelsInputtothesimulationmodelshasbeendeterminedfromexistingdefinitivestudiesoftheSusitnaBasinhydropotentialandfrompublishedandunpublishedUSGSrecords.Inputtothemodelcanbeclassedunderthreemaincategories:reservoirandpowergenerationfacilitydescription,energydemandcurveandinflowrecords.(a)ReservoirandPowerGenerationFacilities(i)ReservoirStorage-ElevationCurvesThestoragecurvesforthesevendamsidentifiedintheSusitnaBasinscreeningmodelhavebeendeterminedfrom50footcontourmapsofthereservoirareasbeingstudied.(ii)ReservoirStorageConstraintsDuetothepossibleenvironmentallimitationstoseasonalanddailydrawdownofthereservoirs,tentativevalueshavebeensettoallowconsistencyincomparisons.Themaximumdailyreservoirfluctua-tion,duetopeakingoperation,hasbeensetatfivefeet.Seasonalfluctuationsvaryaccordingtothesizedreservoir.Thefluctua-tionsassumedaregiveninTableF.l.Theseconstraintsmaybechangedduetomoreinformationon,andanalysesof,theenvironmentalimpactofthesefluctuations.(iii)DownstreamFlowConstraintThisconstraintonlyaffectsdailypeakingoperation.Assuch,itoccasionallylimitstheplantcapabilitytoproduceeitherfullordemandpower.Theflowconstrainthasbeensetsothattheplantatleastgivesapproximatelythehistoricalnterflowinthereachimmediatelydownstreamofthedamsite.FlowconstraintsaregiveninTableF.l.(iv)InstalledCapacityInstalledcapacityforeachofthedamsiteshasbeendeterminedfromtheplansidentifiedduringtheoptimumscreeningofSusitnaBasindevelopments(AppendixE).Insomecasesphasedpowerhousealternativeshavebeenconsideredandareusually50percentoffulldevelopment.InstalledcapacitiesconsideredaregiveninTablesF.3andF.4.F-4 (v)TailwaterElevationandEfficiencyAveragetailwaterelevationshavebeendeterminedfromtopographicalmapsandfrominformationcontainedinreportsofpaststudies.TailwaterelevationsaregiveninTableF.l.Theassessmentofmoreprecisetailwaterelevationratingcurvesdevelopedduringlaterstagesofthestudiesandfurtherdefinitionofchannelgeometryatselecteddevelopmentsiteswillbeundertakenduringdetailedpro-jectfeasibilitystudies.Combinedefficiencyofgenerators,turbinesandpenstocks,etc.hasbeenassumedtobe81percent.Thisvalueisconservativeandisbelievedtobeareasonableassumptionfortheseinitialassess-ments.(b)EnergyDemandCurveThisdistributionhasbeentakenfromstudiesoftheRailbeltregionenergygrowthasdiscussedinSection5.Thedistributionselectedisthatfor1995underamediumloadgrowthscenarioandisgiveninFigureF.1.(c)InflowThestreamflownetworkoftheUpperSusitnaBasinconsistsofthreegagesatGoldCreek(2920),Cantwell(2915)andDenali(2910)ontheSusitnaRiverandoneatMaclarenontheMaclarenRiver(2912).ThelongestrecordisatGoldCreek,whichhas30yearsofrecordfrom1949to1979.Theothershaveshorter,intermittentrecords.Therecordsatthethreegageswithl~ssthan30yearshavebeenextendedbycorrelationwithstreamflowsatGoldCreek.Toestimatethestreamflowateachoftheproposeddamsites,arelationshipbetweendrainageareaandupstreamanddownstreamgagestreamflowwasdetermined.Basically,thisrelationshipwasusedtoestimatethestreamflowatadamsitebyaddingthenearestupstreamgagerecordstotheflowdifferencebetweenthenearestupstreamanddownstreamgageswhichwereproratedtoreflectthedrainageareaatthedamsitewithrespecttothenearestdownstreamgage.ThesestreamflowrelationshipsaregiveninTableF.2.Streamflowsateachdamsiteforthe30yearperiodaregiveninTablesE.1toE.7ofAppendixE.F.6-ModelResultsThescreeningmodelidentifiedpotentialSusitnadevelopmentsconsistingofeithersingledarnsormulti-damdevelopments(AppendixE).Themaindamscon-sideredoptimumfordevelopmentareDevilCanyon,HighDevilCanyon,VeeandWatana.TheoptimizationprocessindicatedthatWatanaandHighDevilCanyonwouldbefirststagedevelopmentsinmulti-damdevelopmentschemes.Second-stagedevelopmentswouldresultinaWatana/DevilCanyonplanandaHighDevilCanyon/Veeplan.F-5 Adjustmentofthespecifiedinstalledcapacitywouldalsoadjusttheenergydemandcurveifthedemandfactorwasheldconstant.Consequently,thedemandfactorusedcoupledwithinstalledcapacitymustbeconsideredonlyasameansofdeterminingtheenergydemandthatcanbesuppliedbyagivenhydropowersystem.Environmentalconstraintsandhydrology(shortagesandsurpluses)leadtoanactualplantfactorwhichisslightlydifferentthanthenominaldemandfactorspecifiedtodeterminedemand.F.5-InputtoSimulationModelsInputtothesimulationmodelshasbeendeterminedfromexistingdefinitivestudiesoftheSusitnaBasinhydropotentialandfrompublishedandunpublishedUSGSrecords.Inputtothemodelcanbeclassedunderthreemaincategories:reservoirandpowergenerationfacilitydescription,energydemandcurveandinflowrecords.(a)ReservoirandPowerGenerationFacilities(i)ReservoirStorage-ElevationCurvesThestoragecurvesforthesevendamsidentifiedintheSusitnaBasinscreeningmodelhavebeendeterminedfrom50footcontourmapsofthereservoirareasbeingstudied.(ii)ReservoirStoraqeConstraintsDuetothepossibleenvironmentallimitationstoseasonalanddailydrawdownofthereservoirs,tentativevalueshavebeensettoallowconsistencyincomparisons.Themaximumdailyreservoirfluctua-tion,duetopeakingoperation,hasbeensetatfivefeet.Seasonalfluctuationsvaryaccordingtothesizedreservoir.Thefluctua-tionsassumedaregiveninTableF.l.Theseconstraintsmaybechangedduetomoreinformationon,andanalysesof,theenvironmentalimpactofthesefluctuations.(iii)DownstreamFlowConstraintThisconstraintonlyaffectsdailypeakingoperation.Assuch,itoccasionallylimitstheplantcapabilitytoproduceeitherfullordemandpower.Theflowconstrainthasbeensetsothattheplantatleastgivesapproximatelythehistoricalwinterflowinthereachimmediatelydownstreamofthedamsite.FlowconstraintsaregiveninTableF.l.(iv)InstalledCapacityInstalledcapacityforeachofthedamsiteshasbeendeterminedfromtheplansidentifiedduringtheoptimumscreeningofSusitnaBasindevelopments(AppendixE).Insomecasesphasedpowerhousealternativeshavebeenconsideredandareusually50percentoffulldevelopment.InstalledcapacitiesconsideredaregiveninTablesF.3andF.4.F-4 (v)TailwaterElevationandEfficiencyAveragetailwaterelevationshavebeendeterminedfromtopographicalmapsandfrominformationcontainedinreportsofpaststudies.TailwaterelevationsaregiveninTableF.1.Theassessmentofmoreprecisetailwaterelevationratingcurvesdevelopedduringlaterstagesofthestudiesandfurtherdefinitionofchannelgeometryatselecteddevelopmentsiteswillbeundertakenduringdetailedpro-jectfeasibilitystudies.Combinedefficiencyofgenerators,turbinesandpenstocks,etc.hasbeenassumedtobe81percent.Thisvalueisconservativeandisbelieved tobeareasonableassumptionfortheseinitialassess-ments.(b)EnergyDemandCurveThisdistributionhasbeentakenfromstudiesoftheRailbeltregionenergygrowthasdiscussedinSection5.Thedistributionselectedisthatfor1995underamediumloadgrowthscenarioandisgiveninFigureF.1.(c)InflowThestreamflownetworkoftheUpperSusitnaBasinconsistsofthreegagesatGoldCreek(2920),Cantwell(2915)andDenali(2910)ontheSusitnaRiverandoneatMaclarenontheMaclarenRiver(2912).ThelongestrecordisatGoldCreek,whichhas30yearsofrecordfrom1949to1979.Theothershaveshorter,intermittentreco~ds.Therecordsatthethreegageswithlessthan30yearshavebeenextendedbycorrelationwithstreamflowsatGoldCreek.Toestimatethestreamflowateachoftheproposeddamsites,arelationshipbetweendrainageareaandupstreamanddownstreamgagestreamflowwasdetermined.Basically,thisrelationshipwasusedtoestimatethestreamflowatadamsitebyaddingthenearestupstreamgagerecordstotheflowdifferencebetweenthenearestupstreamanddownstreamgageswhichwereproratedtoreflectthedrainageareaatthedamsitewithrespecttothenearestdownstreamgage.ThesestreamflowrelationshipsaregiveninTableF.2.Streamflowsateachdamsiteforthe30yearperiodaregiveninTablesE.1toE.7ofAppendixE.F.6-ModelResultsThescreeningmodelidentifiedpotentialSusitnadevelopmentsconsistingofeithersingledarnsormulti-damdevelopments(AppendixE).Themaindamscon-sideredoptimumfordevelopmentareDevilCanyon,HighDevilCanyon,VeeandWatana.TheoptimizationprocessindicatedthatWatanaandHighDevilCanyonwouldbefirststagedevelopmentsinmulti-damdevelopmentschemes.Second-stagedevelopmentswouldresultinaWatana/DevilCanyonplanandaHighDevilCanyon/Veeplan.F-5 Thesimulationmodelswereruntoestimateenergyyieldsfromthesinglereser-voirdevelopments(WatanaandHighDevilCanyon),andthenfrombasindevelop-ments(Watana/DevilCanyonandHighDevilCanyon/Vee).Theaverageannualenergylevelsobtainedfromthevariousdevelopmentplanspossible(stagedpowerhouse,stageddams,etc.)aregiveninTableF.3andF.4.DetailsofmonthlyaverageenergyandmonthlyfirmenergyaregiveninTablesF.5toF.15.F.7-InteractionofOGP5Thefinalplantfactorandthemonthlypeakratiosordemandcurvearedeter-minedinaninteractiverunwithOGP5.Basically,theinputofthesimulationresultstoOGP5canbeassumedtoapplytovariousinstalledcapacitiesprovidedtheenergydemandcurve determinedinthesimulationprocedureisnotviolated.OGP5thenselectsoptimumplantfactors(andinstalledcapacity)whichthenformsthebasisfornewreservoirsimulationwork.F-6 TABLEF.1-RESERVOIRANDFLOWCONSTRAINTSMaXl.ffiUmDOwnstreamNormalSeasonalCompensationTailwaterMaximumDrawdownFlowElevationElevationDam(ft)(cfa)(rt)(ft)DevilCanyon10020008801450HighDevilCanyon100200010201750Watana150200014652200Vee150200019052350 TABLEF.2-DAMSITESTREAMFLOWRELATIONSHIPuralnageSiteAreaDischargeRelationshipGoldCreek(g)6160QgCantwell(c)4140QcDenali(d)950QdDevil'Canyon(DC)5B10~C=0.827(Q-Q)+Q9c cHighDevilCanyon(HOC)5760QHOC=0.802(Qg-Qc)+QcWatana(W)5180QW=0.515(Q-Q)+Q9c cSusitnaIII(S)4225Qs=0.042(Q-Q)+Q9c cVee(V)4140QV=QcDenali(D)950~=0.153(Q-Q)+Qd9 cMaclaren(M)2319~=0.429(Q-Q)c d+Qd TABLE F .3.SUSITNA DEVELOPMENT PLANS CUffiulatl.ve Stage/Incremental Data System Data Annual Maximum Energy Capital Cost Earliest Reservoir Seasonal Production Plant $Hi lUans On-line Full Supply Draw-Firm Avg.Factor (1980 values)1 ~Plan Stage Construction Date Level -ft.down-ft GWH GWH.ro 1 .1 1 Watana 2225 ft 800MW 1860 1993 2200 150 2670 3250 46 2 Devil Canyon 1470 ft 600 MW 1000 1996 1450 100 5500 6230 51 TOTAL SYSTEM 1400 MW ~ 1.2 1 Watana 2060 ft 400 MW 1570 1992 2000 100 1710 2110 60 2 Watana raise to 2225 ft 360 1995 2200 150 2670 2990 85 3 Watana add 400 MW capacity 130 2 1995 2200 150 2670 3250 46 4 Oevil Canyon 1470 ft 600 MW 1000 1996 1450 100 5500 6230 51 TOTAL SYSTEM 1400 MW )1Jb!l" 1.3 1 Watana 2225 ft 400 MW 1740 1993 2200 150 2670 2990 85 2 Watana add 400 MW capacity 150 1993 2200 150 2670 3250 46 3 Devil Canyon 1470 ft 600 MW 1000 1996 1450 100 5500 6230 51 TOTAL SYSTEM 1400 MW 'lIl'm TABLE F.3 (Continued) --~-~-~CumlJlat~ve Stage/Incremental Data System Data Annual Maximum Energy Capital Cost Earliest Reservoir Seasonal Production Plant $Millions On-line Full Supply Draw-Firm Avg.Factor Plan (198D values)1 Stage Construction Date Level -ft.down-ft.GWH GWH % 2.1 1 High Devil Canyon 1775 ft 800 MW 1500 1994 3 1750 150 2460 3400 49 2 Vee 2350 ft 400 MW 1060 1997 2330 150 3B70 4910 47 TOTAL SYSTEM 1200 MW "Z5Oll" 2.2 1 High Devil Canyon ~ 1630 ft 400 MW 1140 1993'1610 100 1770 2020 58 2 High Devil Canyon add 400 MW Capacity raise dam to 1775 ft 500 1996 1750 150 2460 3400 49 3 Vee 2350 ft 400 MW 1060 1997 2330 150 3870 4910 47 TOTAL SYSTEM 1200 MW 'TTlJlj 2.3 1 High Devil Canyon 1775 ft 400 MW 1390 1994 3 1750 150 2400 2760 79 2 High Devil Canyon add 400 MW capacity 140 1994 1750 150 2460 3400 49 3 Vee 2350 ft 400 MW 1060 1997 2330 150 3870 4910 47 TOTAL SYSTEfl 1200 MW 'Z'5'lU 3.1 1 Watana 2225 ft 800 MW 1860 1993 2200 150 2670 3250 46 2 Watana add 50 MW tunne I 330 MW 1500 1995 1475 4 4B90 5430 53 TOTAL SYSTEM 1180 MW 136'1f TABLE F.3 (Continued) Stsgeilncremental ~umIJ~al:.IVB Data System Data Annua t Maximum Energy Capital Cost Earliest Reservoir Seasonal Production Plant $Millions On-line Full Supp ly Draw-Firm Avg.Factor (19BD values)1 "Plan Stage Construction Date Level -ft.down-ft.GWH GWH ~ 3.2 1 Watana 2225 ft 400 MW 1740 1993 2200 150 2670 2990 85 2 Watana add 400 MW capacity 150 1994 2200 150 2670 3250 46 3 Tunnel 330 MW add 50 MW to Watana 1500 1995 1475 4 4890 5430 53 »'lIT 4.1 1 Watana 2225 ft 400 MW 1740 1995 3 2200 150 2670 2990 85 2 Watana add 400 MW capacity 150 1996 2200 150 2670 3250 46 3 High Devil Canyon 1470 ft 400 MW 860 1998 1450 100 4520 5280 50 4 Portage Creek 1030 ft 150 MW 650 2000 1020 50 5110 6000 51 TOTAL SYSTEM 1350 MW )1i1JIJ" NOTES: (1)Allowing for a 3 year overlap construction period between major dams. (2)Plan 1.2 Stage 3 is less expensive than Plan 1.3 Stage 2 due to lower mobilization costs. (3)Assumes FERC license can be filed by June 1984,ie.2 years later than for the Watana/Devil Canyon Plan 1. TABLE F.4.SUSITNA ENVIRONMENTAL OEVELOPMENT PLANS CUffiulatlve Stage/Incremental Data System Data Mnua ( Maximum Energy Capital Cost Earliest Reservoir Seasonal Production Plant $Millions On-line Full Supply Draw-Firm Avg.Factor Plan Stage (1980 values)1ConstructionDate Level -ft.down-ft GWH GWH.% E1.1 1 Watana 2225 ft 800MW and Re-Regulation Dam 1960 1993 2200 150 2670 3250 46 2 Oevil Canyon 1470 ft 40IJMW 900 1996 1450 100 5520 6070 58 TOTAL SYSTEM 1200MW '2llb!T E1.2 1 Watana 2060 ft 400MW 1570 1992 2000 100 1710 2110 60 2 Watana raise to 2225 ft 360 1995 2200 150 2670 2990 85 3 \~atana add 400MW capacity and Re-Regulation Dam 230 2 1995 2200 150 2670 3250 46 4 Devil Canyon 1470 ft 400l>1W 900 1996 1450 100 5520 6070 58 TOTAL SYSTEM 1200MW )1J6l'f E1.3 1 Watana 2225 ft 400MW 1740 1993 2200 150 2670 2990 85 2 Watana add 40Of~ capacity and Re-Regulation Dam 250 1993 2200 150 2670 3250 46 3 Devil Canyon 1470 ft 400 MW 900 1996 1450 100 5520 6070 58 TOTAL SYSTEM 1200MW '2'!l'JIT Maximum Energy Capital Cost Earliest Reservoir Seasonal Pl."oduction Plant $ME lions On-line Full Supply Draw-Firm Avg.Factor Plan Stage Construction (1980 values)1Date Level -ft.down-ft.GWH GWH % E2.4 1 High Devil Canyon 1755 ft 40flMW 1390 1994 3 1750 150 2400 2760 79 2 High Devil Canyon add 480MW capacity and Portage Creek Dam 150 ft 790 1995 1750 150 3170 4080 49 3 Vee 2350 ft 400MW 1060 1997 2330 150 4430 5540 47 TOTAL SYSTEM mrr E3.2 1 Watana 2225 ft 400MW 1740 1993 2200 150 2670 2990 85 2 Watana add 400 MW capacity and Re-Regulation Dam 250 1994 2200 150 2670 3250 46 3 Watana add 50MW Tunnel Scheme 330MW 1500 1995 1475 4 4890 5430 53 TOTAL SYSTEM 1180MW '3'1i9!f E4.1 1 Watana , 2225 ft 400MW 1740 1995'2200 150 2670 2990 85 2 Watana add 400MW capacity and Re-Regulation Dam 250 1996 2200 150 2670 3250 46 3 High Devil Canyon 1470 ft 400MW 860 1998 1450 100 4520 5280 50 4 Portage Creek 1030 ft 150MW 650 2000 1020 50 5110 6000 51 TOTAL SYSTEM 1350 MW >sm NOTES: rrr--Allowing for a 3 year overlap construction period between major dams. (2)Plan 1.2 Stage 3 is less expensive than Plan 1.3 Stage 2 due to lower mobilization costs. (3)Assumes FERC license can be filed by June 1984,ie.2 years later than for the Watana/Devil Canyon Plan 1. TABLE F.4 (Continued) Cumulative Stage/Incremental Data System Data Annual Maximum Energy Capital Cost Earliest Reservoir Seasonal Production Plant $Millions On-line Full Supply Draw-Firm Avg.Factor Plan Stage (19BO values)1ConstructionDate Level -ft.down-ft.GWH GWH % E1.4 1 Watana 2225 ft 400MW 1740 1993 2200 150 2670 2990 B5 2 Devil Canyon 1470 ft 40OM\~900 1996 1450 100 5190 5670 81 TOTAL SYSTEM 800MW Uiiii E2.1 1 High Devil Canyon 1 775 ft 800MW and Re-ReglJ lation Dam 1600 1994 3 1750 150 2460 3400 49 2 Vee 2350ft 400MW 1060 1997 2330 150 3870 4910 47 TOTAL SYSTEM 1200MW T660 E2.2 1 High Devil Canyon 1630 ft 40DMW 1140 1993 3 1610 100 1770 2020 58 2 High Devil Canyon raise dam to 1775 ft add 400MW and Re-Regulation Dam 600 1996 1750 150 2460 3400 49 3 Vee 2350 ft 400 MW 1060 1997 2330 150 3870 4910 47 TOTAL SYSTEM 1200MW TsiJii E2.3 1 High Devil Canyon 177 5 ft 400MW 1390 1994 3 1750 150 2400 2760 79 2 High Devil Canyon add 400MW capacity and Re-Regulation Dam 240 1995 1750 150 2460 3400 49 3 Vee 2350 ft 400MW 1060 1997 2330 150 3870 4910 47 TOTAL SYSTEM 1200 2690 TABLEF.5-PLAN1.1-ENERGIESSTAGE1STAGE2AddOev11CanyonMONTHWatana(2200)(1450)BOOMW600MWEAEFEAEF(GWH) (GWH)(GWH) (GWH)JANUARY26426354253BFEBRUARY250249514511MARCH224224452458APRIL201201394406MAY186186418405JUNE187183437383JULY285183473373AUGUST499190707394SEPTEMBER370204667421OCTOBER233ZJ3488478NOVEMBER266266544540OECEMBER2B7287591587TOTALANNUAL3252266962275494Notes:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(2200):Reservoirfullsupplylevel TABLEF.6-PLAN1.2-ENERGIESSiAGE3(1)51AGE1stAGE4Watana(2000)RaiseWatana(2200)AddDev~1CanyonMONTH400MWAdd400MW(1450)400MWEAEFEAEFEAEF(GWH)(GWH)(GWH)(GWH)(GWH) (GWH)JANUARY13B13726426354253BFEBRUARY130129250249514511MARCH117116224224452458APRIL10357201201394406MAY1001001B618641B405JUNE154102187 183437383JULY3221032851B3473373AUGUST355365499190707394SEPTEMBER26918B370204667421OCTOBER131123233 23348B478NOVEMBER140139266266544540DECEMBER150149287287591587TOTALANNUAL210917083252266962275494Notes:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(2000):Reservoirfullsupplylevel(ft)(1)Stage2isasforStage1onTableF.6(Plan1.3) TABLEF.7-PLAN1.3-ENERGIESSIAGE1STAGeZSTAGe3Watana(2200)Add400MWtoAddDevilCanyonMONTH400MWWatana(2200)(1450)400MWEAITeAEFEAEF(GWH) (GWH)(GWH)(GWH)(GWH)(GWH)JANUARY263 26326426354253BFEBRUARY250 249250249514511MARCH224 224224224452 458APRIL201 201201201394406MAY186 186186 186418405JUNE187 184187183437383JULY245183285183473373AUGUST333190499190707394SEPTEM8ER315204370204667421OCT08ER233233233 233488 478NOVEMBER266 265266266544540DECEMBER287 2872B72B7591587TOTALANNUAL2990 26693252266962275494Notes:EA:AverageMonthlylnergyEF:MonthlyFirmEnergy(2000):Reservoirfullsupplylevel(ft) TABLEF.B-PLAN2.1-ENERGIESSTAGE1STAGE2MONTHHighDevilCanyonAddVee(2355)(1750)BOOMW400MWEAEFEAEF(GWH)(GWH)(GWH) (GWH)JANUARY235 23236B368FE8RUARY222219349 350MARCH197151303313APRIL17330268276MAY169171254258JUNE231172290247JULY480173526319AUGUST554307752298SEPTEM8ER429303575280OCTOBER219213394 366NOVEMBER239233403393DECEMBER257254425401TOTALANNUAL3405245849073869Notes:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(1750):Reservoirfullsupplylevel(ft) TABLEF.9-PLAN2.2-ENERGIESStAGE1STAGEZSTAGE3RaiseH1ghDevilAddVee(2330)Hi{hDevilCanyonCanyon(1750)400MWMONTH1610)400MWTotal1200MWEAEF.EAEFEAEF(GWH)(GWH)(GWH)(GWH)(GWH)(GWH)JANUARY11711623523236B36BFEBRUARY110 109222219349350MARCH999B197141303313APRIL898717330268276MAY9Z87169171254258JUNE26593231172290247JULY29Z291480173526319AUGUST29029Z55430775229BSEPTEMBER270 243429303575280OCTOBER150105219213394366NOVEMBER120 119239 233403393DECEMBER129127257254425401TOTALANNUAL20n17672759241549073869Notes:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(1610):Reservoirfullsupplylevel(ft) TABLEF.10-PLANS2.3andE2.3-ENERGIESH'?hg~e!I~anyonS~A5E2S~4GE~MdOMWtoAddee(530)MONTH1750)400MWHighDevilCanyon400MWEAEFEAEFEAEF(GWH)(GWH)(GWH)(GWH) (GWH)(GWH)JANUARY23523223523236B 36BFEBRUARY222219222219349350MARCH197141197152303313APRIL173301733026B276MAY169171169171254258JUNE200172231172290 247JULY2751734BO173526319AUGUST2BB2B6554307752298SEPTEMBER2B5292429303575280OCTOBER219213219 213394366NOVEMBER239 232239233403393DECEMBER257254257254425401TOTALANNUAL2759 24153405245949073869Notes:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(1750):Reservoirfullsupplylevel(ft) TABLEF.11-PLAN3.1-ENERGIES51AGE151AGE2Watana(2200)AddTunnelMONTH800MW380MWEAEFEAEFJANUARY264263490488FEBRUARY250249463467MARCH224 224411423APRIL201201364376MAY186186345351JUNE187183332 332JULY285183390321AUGUST499190633337SEPTEMBER370204574364OCTOBER233 233419417NOVEMBER2662664B3481DECEMBER287 287529527TOTALANNUAl32522669543348B5Notes:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(2200):Reservoirfullsupplylevel(ft) TABLEF.12-PLAN4.1-ENERG!ESSTAGE1STAGE2StAGE3Watana(220d)AddH.O.C.AddPortagaCreekMONTH800MW(1450)400MW(1020)150MWEAEFEAEFEAEF(GWH) (GWH)(GWH) (GWH)(GWH)(GWH)JANUARY264 263447444504501FEBRUARY250 249424 422 478476MARCH224 224379378428426APR!L201 201334335 379 378MAY186 186338330391376JUNE187183349313406356JULY285183419306481347AUGUST499190670323799366SEPTEM8ER370204583346661392OCTOBER233 233400393454445NOVEM8ER266265499446507503DECEMBER287287488485550546TOTALANNUAL32522669528145225997 5112~:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(2200):Reservoirfullsupplylevel(ft) TABLEF.13-PLANE1.2-ENERGIESSTAGE2(1)STAGE3STAGE4WatanaHalseDamAdd400MWtoAddDevl!CanyonMONTH(2200)400MWWatana(2200) (1450)400MWEAEFEAEFEAEF(GWH)(GWH)(GWH) (GWH)(GWH) (GWH)JANUARY263263264263544560FEBRUARY250249250249515 516MARCH224224224224450460APRIL201201201 20139640BMAY1B61861B61B6419406JUNE1B71841B71B34363B5JULY2451B32B5183453375AUGUST333190499190616395SEPTEMBER315204370204606423OCTOBER2332332332334904BONOVEMBER266265266266547545DECEMBER2872B72872875945B9TOTALANNUAL299026693252266960655520Notes:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(2200):Reservoirfullsupplylevel(ft)(1)Staga1isasforStage1onTable2Plan(1.2) TABLEF.14-PLANE1.)-ENERGIESSTAGE1-STAGEZSIAGE3Watana(2200)Add400MWtoAddDevilCanyonMONTH400MWWatana(1450)400MWEAEFEAEFEAEF(GWH) (GWH)(GWH)(GWH) (GWH)(GWH)JANUARY26)26)26426)544560FEBRUARY2502~9250249515516MARCH224224224224450460APRIL201 201201 201)9640BMAY186 186186186419406JUNE18718418718)4)6)85JULY24518)28518)45)315AUGUST)))190499190616)95SEPTEMBER)1520437020460642)OCT08ERZ)Z)2)J2»490480NOVEMBER266 265266 266547545OECEMBER287287287 287594589TOTALANNUAL299026693252266960655520~:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(2200):Reservoirfullsupplylevel(ft) TA8LEF.1'-PLANE2.4-ENERGIESSTAGE1STAGE2SfAGE3Add400MWtoHighMONTHHi~hDevilCanyonDevilCanyonandPor-AddVee(23,0)17,0)400MWtageCreek(1'0MW)400MWEAEFEAEFEAEF(GWH)(GWH)(GWH)(GWH)(GWH)(GWH)JANUARY23,232317317432435FE8RUARY222219296302411415MARCH197141261270360372APRIL17330231239318328MAY169171220221287 290JUNE200172232208321277JULY275173460214564349AUGUST288 286629221820332SEPTEM8ER285 292492241646315OCTOBER219213282276447 415NOVEM8ER239 2323173174,7446OECEM8ER257 254346346480456TOTALANNUAL275924154083317155434430Notes:EA:AverageMonthlyEnergyEF:MonthlyFirmEnergy(1750):Reservoirfullsupplylevel(rt) FIGUREF.III~IRI1.00I-.92.92.87I-.80.78.70.70I-.64.64.62.611995MONTH/ANNUALPEAKLOADRATIOSNOVDECSEPOCTJUNJULAUGMONTHJANFE8MARAPRMAYREF:WOODWARDCLYDECONSULTANTS,'.'FORECASTINGPEAKELECTRICDEMANDFORALASKA'SRAIL8ELT"1.0.9.8Q~Q:.7:.:«UJa...J.6«::>zz«.50I-:.:.4«UJa.>-.3..J~Z0:=;;.2 APPENDIXG -SYSTEMWIDEECONOMICEVALUATIONTheRailbeltSystemwillbedevelopedinthefuturebymeansofanappropriatecontinuationofexistingandnewprovengenerationalternativestosupplythenecessarydemand.TheobjectivesofgenerationplanningintheevaluationprocessistodeterminethepreferredSusitnaBasindevelopmentplanwhichwillformpartoftheRail-beltSystem.ThepreferredSusitnaBasinplanwouldbethatplanwhichgivesthelowestsystempresentworthcostofgenerationfortheenergyandcapacitydemandsandeconomiccriteriaselected.G.1-IntroductionGenerationplanninganalyseswereperformedbymakingacomparisonofSusitnaBasindevelopmentalternativeswiththeaidofaproductioncostmodeltoassessthesystemcostsforthevariousdevelopmentalternativesavailable.Standardnumericalevaluationtechniqueswerethenusedtomakedirectcomparisonofal-ternatives.Initially,asetofvariableswasestablishedforuseinmakingbroadcomparisonsofavailablebasindevelopments.Inthispreliminaryevalua-tion,thestudyfocusedonthemediumloadforecasttoidentifyvariousplans;abaseplanwhichconsistedofanall-thermaldevelopment,planscomposedofther-malplusvariousSusitnadevelopments,andaplancomposedofthermalplusotherhydroelectricdevelopments.Thesecondphaseofgenerationplanningassessedtheimpactofvaryingtheloadforecast.SystemgenerationplanswithandwithouttheSusitnaBasindevelop-mentplanwereidentifiedforthehighandlowloadforecasts.Aplanwasalsodevelopedforthelowloadforecastconsideringanadditionalreductioninloadgrowthduetoconservationandloadmanagement.Alsounderthisphase,aplanwasdevelopedconsideringaprobabilisticforecastcenteredaroundthemediumloadforecast.Sinceitisrecognizedthattheselectionofagenerationplanmaybesensitivetotheunderlyingassumptions,thethirdphaseofgenerationplanningassessedtheimpactsofvariableplanningparametersandthesensitivityofthesepara-meterswithrespecttothegenerationplans.Thisanalysisdealtwithvariableinterestrates,fuelcostandescalation,retirementpolicies,andcapitalcostestimates.G.2-GenerationPlanningModels(a)SelectionofPlanningModelThemajortoolusedintheeconomicevaluationofthevariousRailbeltgen-erationplansisacomputergenerationsystemsimulationprogram.Thereareanumberofgenerationplanningmodelsavailablecommerciallyandac-ceptedforuseintheutilityindustrythatwillsimulatetheoperation,growthandcostofaelectricutilitysystem.Someofthemorewidelyusedmode1sinc1udethefo11owing:G-l -GENOP-OGP5-PROMOD-WASPbyWestinghousebyGeneralElectric.byEnergyManagementAssociates.byTennesseeValleyAuthority.TheWASPprogramwasnotavailableforuseatthestartofthisstudysoisnotconsideredordiscussedfurtherinthisreport.Keyconsiderationsforuseinselectionofamodelforthisstudyaredataprocessingcosts,methodofproductioncostmodeling,treatmentofsystemreliability,selectionofnewcapacity,dispatchingofhydroelectriccapa-citytomeetloadprojectionsandabilityofthemodeltoaddressloaduncertainty.Althoughtheseitemsarehandleddifferentlyineachprogram,commontraitsofoperationexist.SomeofthesalientfeaturesofeachmodelareshownonTableG.l.Majordifferencesinthemodelsaregivenbelow.(i)ForcedOutagesOnesignificantfactorwhichvariesbetweenthemodelsisthemethodofdeterminingforcedoutagesofthevariousunitsofsystempowergenerationinstallationswhicharerepresentedintheproductioncostalgorithm.Thethreemethodsusedare:-Deterministicmethodswhichdevoteunitcapacitybyamultiplierorbyextendingplannedmaintenanceschedules.-Stochasticmethodswhichcanbereducedtodeterministicmethods.Strictlyspeakingstochasticrepresentationsofoutagesisarandomselectionofsomeunitsineachcommitmentzonetobeputoutofservice.Theloadpreviouslyservedwillbetransferredtohighercostunits.-Probabilisticmethods,whicharedescribedbythemodifiedBooth-Baleriauxmethodofproductionsimulationwhichallowsforprobabilitydistributionofgenerationunitoutages.Theselectionofoneofthesemethodsmaybecriticalintheuseofamodelforshort-termoutagescheduling.However,itisgenerallyfoundthatvirtuallynodifferenceinplanningresultsisobtainedfrommodelsusingthethreemethodsavailableoveralongtermperiod.(ii)DispatchingHydropowerResourcesThemethodofdfspatchinghydropowerresourcestomeetloaddemandsisanothersignificantfeaturewhichaffectsthemodel'srepresentationofthesystem.TheGENOPprogramwilldispatchorselect,fromavail-ableunits,hydroelecricunitsfirsttomeetagivendemand.Gen-erally,therun-of-riverunitswillmeetloaddemandandunitswithstoragecapabilitywillbeusedtoshavepeakdemands.G-2 TheOGP5programusesasimilarmethod,utilizinghydroelectricenergyasmuchaspossibletominimizesystemoperatingcosts.Hydropowerisscheduledfirstonamonthlybasistoaccountforseasonalconditions.Anadditionalfeatureoftheprogramistheabilitytousedryyearorfirmenergyonamonthlybasistodeterminesystemreliability,whileusingaverageannualenergytodeterminesystemproductioncosts.ThePROMODprogramallowsforthree1eve1sofannualrunoffandassociatedhydroelectricenergy.Theseenergylevelscanbeenteredintotheprograminaprobabilisticmannertobeusedindeterminingreliabilityandproductioncosting.Run-of-riverandstorageunitsaredispatchedasintheotherprograms.Otherfactorsarealsoimportantsuchasprogramavailabilityandex-perienceofstaffinusingthemodels.Onthebasisofthisassessmentofmodelfeatures,modelavailabilityandAcres'knowledgeoftheintricaciesofthemodelprocedures,theOGP5modelwasselectedforuseinthisstudy.ThismodelisbelievedtobethemostappropriatetoaccuratelymodeltheRailbeltgenerationsystemasitexiststodayandinthefuture,withthevariousgenerationalternativesavailabletotheregion.OGP5ModelTheprimarytoolusedforthegenerationplanningstudieswasthemathema-ticalmodeldevelopedbytheElectricUtilitySystemsEngineeringDepart-mentoftheGeneralElectricCompany.ThemodeliscommonlyknownasDGP5orOptimizedGenerationPlanningModel.Thefollowinginformationispara-phrasedfromGEliteratureontheprogram.TheOGP5programwasdevelopedovertenyearsagotocombinethethreemainelementsofgenerationexpansionplanning(systemreliability,operatingandinvestmentcosts)andautomategenerationadditiondecisionanalysis.OGP5willautomaticallydevelopoptimumgenerationexpansionpatternsintermsofeconomics,reliabilityandoperation.ManyutilitiesuseOGP5tostudyloadmanagement,unitsize,capitalandfuelcosts,energystorage,forcedoutagerates,andforecastuncertainty.TheOGP5programrequiresanextensivesystemofspecificdatatoperformitsplanningfunction.Indevelopinganoptimalplan,theprogramconsid-erstheexistingandcommittedunits(plannedandunderconstruction)availabletothesystemandthecharacteristicsoftheseunitsincludin9age,heatrate,sizeandoutageratesasthebasegenerationplan.Theprogramthenconsidersthegivenloadforecastandoperationcriteriatodeterminetheneedforadditionalsystemcapacitybasedongivenreliabil-itycriteria.Thisdetermines"howmuch"capacitytoadd and"when"itshouldbeinstalled.Ifaneedexistsduringanymonthlyiteration,theprogramwillconsideradditionsfromalistofalternativesandselecttheavailableunitbestfittingthesystemneeds.Unitselectionismadebycomputingproductioncostsforthesystemforeachalternativeincludedandcomparingtheresults.G-3 Themodelisthenfurtherusedtocomparealternativeplansformeetingvariableelectricaldemands,basedonsystemreliabilityandproductioncostsforthestudyperiod.Furtherdiscussionontheloadrequirements,loaduncertaintyandplantreliabilityisgivenbelow:(i)LoadRepresentationBesidesgenerationunitdataandsystemreliabilitycriteria,theprogramusesamodelofthesystemloadincludingmonthtoyearpeakloadratios,typicaldailyloadshapesfordaysandweekends,andprojectedgrowthfortheperiodofstudyintermsofcapacityandenergysupply.Loadforecasts'usedforgenerationplanningarerepresentedindetailinSection5,"RailbeltLoadForecast",ofthemainreport.FigureG.1depictsthefourenergyforecastsinthesystemwideanalysis.Theunitresultinginaddedtothesystem.costsiscompletedtoaddtothesystem.thelowestsystemproductioncostisselectedandFinally,aninvestmentcostanalysisofthecapitalanswerthequestionof"whatkind"ofgenerationtoTheforecastsusedforgenerationplanningarebasedonAcres'analysisoftheISERenergyforecast.TheenergyforecastusedbyAcresforestablishingthe"basecase"generationplanisthemediumloadforecast(TableG.2).SensitivityanalyseshavealsobeenundertakenusingvariableloadsdevelopedfromtheISERscenariosofhighandlowlevelsofbotheconomicactivityandgovernmentspending.TableG.2givestherangeofloadforecastsconSidered.TheenergyandloadforecastsdevelopedinSection5ofthisreportincludeenergyprojectionsforself-suppliedindustrialandmilitarysectors.ThesemarketswillnotbeapartofthefutureelectricaldemandtobemetbytheRailbeltUtilityCompany.Likewise,thecapacityownedbythesesectorswillnotbeavailableasasupplytothegeneralmarket. Areviewoftheindustrialselfsuppliersindicatesthattheyareprimarilyoffshoreoperations,drillingoperationsandothersvlhichwouldnotlikelyaddnordrawpowerfromthesystem.Theforecastshavebeenappropriatelyadjustedforuseingenerationplanningstudies,asdescribedinSection5.Additionally,althoughitisconsideredlikelythatthemilitarywouldpurchaseavailablecosteffectivepowerfromageneralmarket,muchoftheircapacityresourceistiedtodistrictheatingsystems,andthuswouldbeexpectedtocontinueoperation.Forthesereasonsonly30percentofthemilitarygenerationtotalwillbeconsideredasaloadonthetotalsystem.Thisamountisabout4percentoftotalenergyin1980anddecreasest~2.5percentin1990.Thismethodofaccountingfortheseloadshasnosignificanteffectontotalcapacityadditionsneededtomeetprojectedloadsafter1985.TableG.2illustratesthemediumloadandenergyforecastsatfiveyearintervalsthrou9houttheplanningperiod.G-4 (ii)LoadUncertaintyTheloadforecastusedtodevelopagenerationplanwillhaveasigni-ficantbearingonthenatureoftheplan.Inaddition,theplancanbesignificantlychangedduetouncertaintiesassociatedwiththeforecastedloads.Toaddressthe questionoftheimpactofloadun-certaintyonadevelopmentplan,twoprocedureswillbeused.Thefirstprocedurewillbetodevelopplansusingthehighandlowloadforecastsassumingnouncertaintytotheforecast.ThiswillidentifytheupperandlowerboundsofdevelopmentwhichwillbeneededintheRailbelt.Thesecondmethodwillbetoincorporatethevariablefore~castsanduncertaintyoftheloadforecastsintotheplanningpro-cess.Themediumloadforecast(usedinpreliminaryevaluationofplans)isintroducedintotheprogramindetail.Thiswouldincludedailyloadshapes,monthlyvariabilityandannualgrowthofpeaksandenergy.Additionalvariablesareaddedwhichintroduceforecastuncertaintyintermsofhigherandlowerlevelsofpeakdemandandtheprobabilityoftheoccurrenceoftheseforecasts.Forexample,intheyear2000themediumloadforecastdemandenteredis1175MW.Variableforecastsareenteredfor950,1060,1530and1670MW,withassociatedprobabil-itiesofoccurrenceof0.10,0.20,0.20and0.10,respectively.Themiddlelevelforecastof1175MWwouldhaveaprobabilityofoccur-renceof0.40.TheOGP5programusesthisvariableforecastindetermininggeneratingsystemreliabilityonly.Alossofloadprobabilityiscalculatedforeachprojecteddemand1eve1ascomparedtotheavailab1ecapacityandaweightedaverageistaken.Thislossofloadprobabilityisthenusedforcapacityadditiondecisions.Aftercapacitydecisionsaremade,theprogramusesthemediumloadforecastdetailforoperatingtheproductioncostmodel.ThismethodofdealingwithuncertaintyisdirectlyapplicabletothedataavailableonRailbeltloadforecasts.Therearefiveforecastswhichcouldbepluggedintothereliabilitycalculations,threebyISERandtwoextremescalculatedbyAcresrepresentedinTableG.2.Subjectivityisreducedtothedecisionofplacingprobabilitiesontheloadforecasts.BasedoncommmunicationwiththeISERgroupinAlaskaaswellasGeneralElectricOPG5personnel,theaboveexampleprobabilitysethasbeenconsideredintheanalysis.Thisisbasedontheassumptionthateachextremeforecastishalfaslikelytohappenastheadjacentforecastwhichisclosertothemedium.TheloadsandprobabilitiesanalyzedaregiveninTableG.3.(iii)GenerationPlantReliabilityInordertoperformastudyofthegenerationsystem,criteriaarerequiredtoestablishgeneratingplantandsystemreliability.ThesecriteriaareimportantindeterminingtheadequacyoftheavailableG-5 generatingcapacityaswellastheslzlngandtimingofadditionalunits.Plantreliabilityisexpressedintheformofforcedandplan-nedoutagerateswhichhavebeenpresentedwithintheindividualre-sourcedescriptionsinSection6.Systemreliabilityisexpressedasthelossofloadprobability(LOLP).AnLOLPforasystemisacalculatedprobabilitybasedonthecharacteristicsofcapacity,forcedandscheduledoutage,andcyclingabilityofindividualunitsinthegeneratingsystem.Theprobabilitydefinesthelikelihoodofnotmeetingthefulldemandwithinaoneyearperiod.Forexample,anLOLPof1relatestotheprobabilityofnotmeetingdemandonedayinoneyear;anLOLPof0.1isonedayintenyears.ForthisstudY,anLOLPof0.1hasbeenadopted.ThisvalueiswidelyusedbyutilityplannersintheUnitedStatesasatargetforindependentsystems.Thistargetvaluewillbeusedbothforthebasecaseplanandforsensitivityanalysesdealingwiththeeffectsofoverorundercapacityavailab1ility.(iv)EconomicandFinancialParametersAsapublicinvestment,itwasdeterminedthattheSusitnaprojectshouldbeevaluatedinitiallyfromaneconomicperspective,usingeco-nomicparameters.InitialanalysisandscreeningofSusitnaalterna-tivesemployedanumericaleconomicanalysisandthegeneralaidoftheOGP5model.Thedifferencesbetweeneconomicandfinancial(costofpower)ana-lysespertaintothefollowingparameters:-ProjectLifeInecpnomicevaluations,aneconomiclifeisusedwithoutregardtotheterms(repaymentperiod)ofdebtcapacityemployedtofinancetheproject.Afinancial(orcostofpower)perspectiveusesanamortizationperiodthatistiedtothetermsoffinancing.Aretirementperiod(policy)isgenerallyequivalenttoprojectlifeineconomiceva1uations;financia1analysismayusearetirementperiodthatdiffersfromprojectlife.-DenominationofCashFlowsandDiscountRatesEconomicevaluationsuserealdollarsandrealdiscountratesthatexcludetheeffectsofgeneralpriceinflationwiththeexceptionoffuelescalation.-MarketorShadowPricesWhenevermarketandshadowpricesdiverge,economicevaluationsuseshadowprices(opportunitycostsorvalues).Financialanalysisusesmarketpricesprojectedasapplicable.FuelpricesarefriscussedindetailinSection6andAppendixB.G-6 -CostEscalationRatesG-7Itshouldbenotedthatthe50-yearlifeforhydroprojectswasselectedasaconservative'estimateanddoesnotincludereplacementinvestmentexpenditures.-30years-35years-20years-30years-30years-50years•Largesteamplants•Smallsteamplants•Gasturbines,oil-fired•Gasturbines,gas-fired'•Diesels•HydroelectricprojectsTocalculateannualcarryingcharges,thefollowingassumptionsweremaderegardingtheeconomiclifeofvariouspowerprojects.Asnotedearlier,theseliveswerealsoassumedastheplantlives.Itisimportanttonotethatapplicationofthevariousparameterscontainedhereinwillnotnecessarilyprovideanaccuratereflectionofthetruelifecyclecostofanysinglegeneratingresourceofthesystem.Fromthepublic(StateofAlaska)perspective,therelevantprojectcostsarebasedonopportunityvaluesandexcludetransferpaymentssuchastaxesandsubsidies.Furtherstudyintothiscomparativeanalysisofprojecteconomicswillbecontinuingduring1981.Incomparison,analysisrequiresanominalormarketrateofinter-estfordiscountedcashflowanalysis.Thisrateisdependentupongeneralpriceinflation,capitalstructure(debt-equityratios)andtax-exemptstatus.Inthebasecase,ageneralrateofpriceinfla-tionofsevenpercentisassumedfortheperiod1980to2010.Givena100percentdebtcapitalizationandathreepercentrealdiscountrate,theappropriatenominalinterestrateisapproximately10percentinthebasecase.Thenomina1interestiscomputedas:NominalInterestRate=(1+inflationrate)x(1+realinterestrate)=1.07x1.03Intheinitialsetofgenerationplanningparameters,itwasassumedthatallcostitemsexceptenergyescalateattherateofgeneralpriceinflation(assumedintheeconomicsensetobe0percentperyear).Thisresultsinrealgrowthratesofzeropercentfor,non-energycostsinthesetofeconomicparametersusedinrealdollargenerationplanning.-InterestRatesandAnnualCarryingChargesTheassumedgenerationp1anningstudybasedoneconomicparametersandcriteriahasa 3percentrealdiscountrateforthebasecaseanalysis.Thisfigurecorrespondstothehistoricalandexpectedrealcostofdebtcapacity.Theissueoftax-exemptfinancingdoesnotimpingeontheseeconomicevaluations. Baseperiod(January1980)energypriceswereestimatedbasedonbothmarketandshadowvalues.Theinitialbasecaseanalysisusedbaseperiodcosts(marketandshadowprices)of$1.15/millionBtu(MMBtu)and$4.00/MMBtuforcoalanddistillaterespectively.Fornaturalgas,thecurrentactualmarketpriceisabout$1.05/MMBtuandtheshadowpriceisestimatedtobe$2.00/MMBtu.Theshadowpriceforgasrepresentstheexpectedmarketvalueassuminganexportmarketwasdeveloped.Realgrowthratesinenergycosts(excludinggeneralpriceinfla-tion)areshowninTableG.4.ThesearebasedonfuelescalationratesfromtheDepartmentofEnergy(DOE)mid-termEnergyFore-castingSystemforDOERegion10(includingtheStatesofAlaska,Washington,OregonandIdaho.Priceescalatorspertainingtotheindustrialsectorwereselectedoverthoseavailableforthecommer-cialandresidentialsectorstoreflectutilities'bulkpurchasingadvantage.Acompositeescalationratehasbeencomputedfortheperiod1980to1995whichreflectsaveragecompoundgrowthrateperyear.SincetheDOEhassuggestedthattheforecaststo1995maybeextendedto2005,thecompositeescalationratesareassumedtopre-vailintheperiod1996to2005.Beyond2005,zerogrowthinenergypricesisassumed.TableG.5summarizesthesetsofeconomicandfinancialparametersassumedforgenerationplanning.-OtherParametersOtherparametersconsideredingenerationplanningstudiesincludeinsuranceandtaxes.Thefactorsforinsurancecosts(0.10 percentforhydroelectricprojectsand0.25percentforallothers)arebasedonFERCguidelines.Stateandfederaltaxeswereassumedtobezeroforalltypesofpowerprojects.Thisassumptionisvalidforplanningbasedoneconomiccriteriasinceallintra-statetaxesshouldbeexcludedastransferpaymentsfromAlaska'sperspective.Thesubsequentfinancialanalysesmayrelaxthisassumptionifnon-zerostateand/orlocaltaxesorpaymentsinlieuoftaxesareiden-tified.AnnualfixedcarryingchargesrelevanttothegenerationplanninganalysisaregiveninTableG.5.G.3-GenerationPlanningResultsGenerationplanningrunsweremadeforeachoftheSusitnadevelopmentplansidentifiedinSection8.6-FormulationofSusitnaBasinDevelopmentPlans,andforsystemgenerationplanswithoutSusitnadevelopments.PlanswithoutSusitnaincludedalternativehydroandall-thermalgenerationscenarios.AminorlimitationinherentintheuseoftheOGP5modelisthatthenumberofyearsofsimulationislimitedto20years.Toovercomethis,thestudyperiodof1980to2040hasbeenbrokenintothreeseparatesegmentsforstudypurposes.Thesesegmentsarecommontoallsystemgenerationplans.G-8 firstsegmenthasbeenassumedtobefrom1980to1990.Themodelofthisimeperiodincludesallcommittedgenerationunitsandisassumedtobecommonallgenerationscenarios.Thisten-yearmodelissummarizedinTableG-8.Thistableshowsthe1980to1990systemconfigurationanddetailsoncommittedunitsandretirementsthatoccurduringtheperiod.Theendpointofthismodelbecomesthebeginningofeach1990-2010model.modelofthefirsttwotimeperiodsconsidered(1980to1990,and1990to)providesthetotalproductioncostsonayear-to-yearbasis.Thesetotalinclude,fortheperiodofmodeling,allcostsoffuelandoperationandntenanceofallgeneratingunitsincludedaspartofthesystem.Intion,thecompletedproductioncostincludestheannualizedinvestmentcostsofanyproductionplansaddedduringtheperiodofstudy.Anumberoffactorsichcontributetotheultimatecostofpowertotheconsumer,arenotincludedinthismodel.Thesearecommontoallscenariosandinclude:-Allinvestmentcoststoplantsinservicepriorto1981;Costsoftransmissionsystemsinservicebothatthetransmissionanddistributionlevel;andAdministrativecostsofutilitiesforprovidingelectricservicetothepublic.,itshouldberecognizedthattheproductioncostsmodeledrepresentonlya.portionofultimateconsumercostsandineffectareonlyaportion,albeitmajor,oftotalcosts.thirdperiod,2010to2040,wasmodeledbyassumingthatproductioncostsofowouldrecurfortheadditional30yearsto2040.Thisassumptionisievedtobereasonablegiventhelimitationsonforecastingenergyandloadrementsforthisperiod.Theadditionperiodto2040isrequiredtotakeintoaccountthebenefitderivedfromthevalueoftheadditionofahydroelectricpowerplantwhichhasausefullifeoffiftyyearsormore.Theselectionofthepreferredgenerationplanisbasedonnumerousfactors.Oneoftheseisthecostofthegenerationplan.Toprovideaconsistentmeans·ofassessing theproductioncostofagivengenerationscenarioeachproductioncosttotalhasbeenconvertedtoa1980presentworthbasis.Thepresentworthcostofanygenerationscenarioismadeupofthreecostamounts.Thefirstispresentworthcost(PWC)ofthefirsttenyearsofstudy(1981to1990),thesecondisthePWCofthescenarioassumedduring1990to2010,andthethirdisthePWCofthescenari0in2010assumedtorecurfortheperiod2010to2040.Inthiswaythelong-term(60years)PWCofeachgenerationscenarioin1980dollarscanbecompared.ThepresentworthcostofthegenerationsystemgivenbyTableG.6is$873.7millionin1980values.ThiscostiscommontoallgenerationscenariosandisaddedtoallPWCvaluesforeachgenerationscenarioduringthemodelingofthesystemintheperiodof1990to2040.G-9 GenerationscenariosanalysesincludethermalgenerationwithSusitnaBasinplans,thermalgenerationwithalternativenon-Susitnahydroplansandall-ther-malgeneration.Detailsoftheanalysisofthesethreegenerationmixesaregiveninthefollowingsections.(a)SusitnaBasinPlans(i)Base CaseMediumLoadForecastEssentiallytheSusitnaBasinplansweredevelopedfromthestudiesdescribedinSection8.Someoftheplansaresimilarinlocationandsizebutvaryinstagingconcepts.Othersareattotallydif-ferentsites.ThesevariousSusitnaplansweremodeledinthe.OGP5modelaspartoftheRailbeltsystem.ThecharacteristicsoftheSusitnaplansaresummarizedinTableG.7andtheirformulationisdescribedfullyinSection8.TheresultsoftheOGP5modelrunsassumingamediumloadforecastforalltheSusitnaplansidentifiedthroughtheproceduresoutlinedinSection8aregiveninTableG.8.Theplansdevelopedincluded800MWand1200MWcapacityplansinadditiontovariationintheseplanstodeterminetheeffectsonPWCofdelayingimplementationoftheplan,theeliminationofastageintheplan,orstagingconstructionofaparticulardamintheplan.InspectionoftheresultsgiveninTableG.8indicatesthefollowing:Thelowestpresentworthcostdevelopmentat$5850millioniseitherPlanEl.lorPlanEl.3(seeTableG.7).ThisresultshowsthatthereisnoeffectivedifferencebetweenfullpowerhousedevelopmentatWatanaandstagedpowerhousedevelopment;-Thehighestpresentworthcostdevelopmentat$6960millionisPlan1.3withDevilCanyonnotconstructed;Watana/DevilCanyon(PlanE1.1orEl.3)issuperiortoWatana/Tunnel(Plan3.1)by$680million;Watana/DevilCanyon(PlanEl.lorEl.3)remainssuperiortoWatana/Tunnel(SpecialPlan3.1)whentunnelcapitalcostsarehalved.Watana/DevilCanyonissuperiorby$380million;Watana/DevilCanyon(PlanE1.1orEl.3)issuperiortoHighDevilCanyon/Veedevelopments(PlanE2.1orPlanE2.3)byatleast$520million;ReplacementofVeeDamwithChakachamnadevelopmentlowerspre-sentworthcostofPlan2.3to$6210million.Watana/DevilCanyonremainssuperiorby$360million;G-10 -Watana/DevilCanyondevelopmentlimitedto800MW(PlanEl.4)is$140millionmorethanfull1200MWdevelopment(PlansEl.lorEl.3)butremainssuperiortotunnelschemeorHighDevilCanyon/Veeplans;.DelayingimplementationofWatana/DevilCanyonPlanEl.3byfiveyearsadverselyaffectspresentcostbyanadditional$220mi11ion;StagingpowerhouseanddamconstructionatWatana(PianEl.2)costs$180millionmorethanPlansE1.1orE1.3;andWatana/HighDevilCanyon/PortageCreek(PlanE4.1)is$200millionmorethaneitherPlanE1.1orE1.3.(ii)VariableLoadForecastAsdiscussedinSection5,themanyuncertainitiesofloadforecast-ingprovideawiderangeofpossibilitiesforfuturegenerationplanning.Themediumloadforecast(withmoderategovernmentexpen-diture)usedabovetoshowthepresentworthcostofthedevelop-mentsidentifiedthroughsitescreeningandplanformulationstepsisthoughttobethemostlikelyloadandenergyforecast.However,duetotheuncertainty associatedwiththeloadforecasting,approx-imateupperandlowerlimitstotheloadforecasthavebeendefined.Thehighforecastassumeshigheconomicgrowthandhighgovernmentexpenditurewhereasthelowerbound,orlowforecast,assumesloweconomicgrowthandlowgovernmentexpenditure.Inadditiontothesetwoforecasts,theresultsofadeterminedeffortatloadmanagementandconservationhavebeenincorporatedintoafourthloadforecast.Thisverylowforecastalsoassumeslowgovernmentexpenditureinadditiontoloweconomicgrowthwithloadmanagementandconservation.FurtherdetailsoftheseforecastsaregiveninSection5andloadforecastvaluesinfive-yearperiodsinTableG.8.TheresultsoftheOGP5analysisoftheRailbeltgenerationsystemwithSusitnaunderthesevariousloadforecastsaregiveninTableG.g.TheconclusionsthatcanbedrawnfrominspectionofTableG.gare:-Watana/DevilCanyondevelopment(PlanE1.4)hastheleastpresentworthcostat$4350millionofalldevelopmentsunderalowloadforecast;-Watana/DevilCanyonwithChakachamnaasafourthstage(modifiedPlanE1.3)hastheleastpresentworthcostof$10,050millionofalldevelopmentsunderahighloadforecast;-PlanE1.4issuperiortospecialWatana/tunnel(tunnelcosthalved)by$380millionunderalowloadforecast;G-11 PlanE1.4issuperiortoHighDevilCanyon/Vee(PlanE2.1)by$320millionunderalowloadforecast;ModifiedPlanE1.3issuperiorby$650milliontoPlanE1.3underahighloadforecast;andModifiedPlanE1.3issuperiortoHighDevilCanyon/VeewithChakachamna(modifiedPlanE2.3)by$990million.(iii)EconomicSensitivityTheWatana/DevilCanyondevelopmentknownasPlanE1.3hasbeenidentifiedasthemosteconomicdevelopmentofSusitnaalternativesunderamediumloadforecast(TableG.8).Inaddition,variationsoftheWatana/DevilCanyondevelopmenthavebeenidentifiedasthemosteconomicalunderlowandhighloadforecasts(TableG.9).Consequently,thePlanE1.3isobviouslythemostreasonabletoselectastheonetodeterminethesensitivityoftheplanstovariationsintheeconomicparameterswhicharesubjecttouncertainties.SensitivityanalyseshavebeenperformedoncriticalparametersandarebasedonPlanE1.3withamediumloadforecast.TheresultsoftheseanalysesaresummarizedinTableG.10andarediscussedbelow.BasevaluesfortheparametersassumedinOGP5modeling,particular-lywithrespecttothermalplantcosts,etc.aregiveninAppendixB.InterestRatesInthebaseplanselected(alsoinotherplans)theinterestrateassumedis3percent.Thisraterepresentsthecostofmoney,netofinflation.Variationofthisrateto5and9percenthasbeenassumedtodeterminetheeffectofinterestratevariationonthiscapitalintensivedevelopment.Theeffectofa 5percentinterestrateistolowerthepresentworthcostofPlanE1.3by$1620millionto$4230million.Thehigherrateof9percentlovlersthepresentworthcostto$2690million.-FuelCostandFuelCostEscalationRateThebaseplanhasassumedafuelcost($/millionBtu)of2.00,1.15,and4.00,fornaturalgas,coalandoilrespectively.Theeffectofreducingfuelcostsby20percentto1.60,0.92and3.20$/millionBtufornaturalgas,coalandoilrespectivelyistoreducethepresentworthcostofPlanE1.3by$590millionto$5260.Thisreductionrepresentsthelowercostassociatedwithoperatingthethermalgenerationcomponentofthesystem.Fuelcostescalationratesof3.98,2.93,and3.58percenthavebeenderivedastypicalfortheRailbeltregion(AppendixB).Theeffectofloweringthisescalationratetozeropercentforall-thermalfuelsistolowerthepresentworthcostofPlanE1.3G-12 -EconomicLifeofThermalPlantsTheeffectsofthesensitivityanalysesconductedabovewouldbethesameforwhicheverdevelopmentplanisselected;therelativerankingofthevariousSusitnaBasindevelopmentplanswouldremainessentiallyunchangedandPlanE1.3wouldstillbethemosteconomicintermsofpresentworthcostunderamediumloadforecast.to$4360million.Whencoalcostescalationaloneissetatzeropercenttheeffectismuchless,givingareductionofonly$590million.Againthefuelcostescalationrateshowsthatthehy-droelectricalternativeswouldbecomeeconomicallysuperiorifthermaloperationcostsarelowered.G-13480MW100MW50MW-ThermalPlantCapitalCostsTheeffectofareductioninthermalplantcapitalcostsby22percent,to350,2135and778$/kwfornaturalgas,coalandoilrespectively,resultsinaslightreductioninpresentworthcostofthesystem.Thereductionis$110millionandisadirectre-sultofthelowercapitalcostsofthethermalcomponentofthesystem.-HydroPlantCapitalCostsVariousuncertaintiesincapitalcostsofthehydrodevelopmentexistduetopossiblevariationsinamountsoffoundationtreat-ment,constructiondelays,etc.Totakeintoaccountsomeoftheseuncertainties,anassessmenthasbeenmadeofincreasedhydroconstructioncosts.Anincreaseinconstructioncostof10percenttoDevilCanyonresultsinanincreaseinpresentworthcostofthesystemof$360million.A50percentincreaseinbothWatanaandDevilCanyonconstructioncostsresultsina$960millionincreaseinpresentworthcost.Increasingtheeconomiclivesof thermalplantsincorporatedintothegenerationsystemwithSusitnaPlanE1.3resultsinanin-creaseofthepresentworthcostofthesystemof$250million.Thisresultwasfora50percentincreaseinthermalplantlifeandshowsthattheincreaseresultsingreateroperationalcosts.-Chakachamna:-Keetna:-Snow:AlternativeHydroGenerationPlansInSection6andAppendixC,alternativehydroelectricdevelopmentstoSusitnawereidentified.InAppendixC,thefollowingtensiteswereshowntobethemost.economicallyviableandenvironmentallyacceptablesitesoutsideoftheSusitnaBasin: IntheOGP5analysesthesesiteswerecombinedintoappropriategroupsonthebasisofleastcostenergyandincorporatedwiththermalgenerationsourcestomeetthemediumloadforecastdefinedearlier(Section5).TheresultsoftheOGP5runsaregiveninTableG.11.-Strandline:-AllisonCreek:-Cache:-Talkeetna-2:-Browne:-Bruskasna:-Hicks:20MW8t1W50MW50MW100MW30Mlj60MW(c)ThermalGenerationScenariosThethermalgeneratingresourcesrequiredtomeetRailbeltenergyandpowerdemandscanbeidentifiedthroughtheuseofthesameproductioncostmodelasthatwhichidentifiedthemosteconomicplanofdevelopmentwithSusitnaBasinalternativesandnon-Susitnahydroalternatives.ThelowestpresentworthcostofthesystemwithalternativeSusitnahydrois$7040million.Thisrepresentsanincreaseof$1190millionoverthelowestcostSusitnadevelopmentplan(PlanE1.3)forthemediumloadfore-cast.ThisalternativehydroscenarioincludesChakachamna,KeetnaandSnowdevelopments.TheadditionofStrandlineLakeandAllisonCreektothesystemhasminimumeffectonpresentworthcost($7041million)butwouldeliminatetheneedof55MWofthermalgeneratingcapacity,thussavinganon-renewableresource.ofalternativehydroconsideredhasapresentworthThesixsitesincludedinthisplanaregiveninThemaximumdevelopmentcostof$7088million.TableG.l1.UsinginformationdevelopedinAppendixBforthermalgeneratingresourcesavailabletotheRailbeltandthefiveloadforecastsoutlinedinSection5,theOGP5programwasusedtosimulatetheoperationoftheRailbeltgeneratingsystemoverthe3D-yearstudyperiod.AsinSusitnaandnon--Susitnahydroalternatives,thelongtermpresentworthcost(in1980dollars)ofthethermalsystemwasdetermined.ThemediumloadforecastiscurrentlybelievedtobethemostlikelyloadtodevelopintheRailbeltoverthenext40years.Consequently,asbeforeforhydrodevelopments,thisforecast'formsthebasisofthemajorityofOGP5analysis.(i)MediumLoadForecast:ThethermalgeneratingplanforthemediumloadforecastispresentedinTableG.11.Twocasesweremodeledforthethermalgenerationplan.Thefirstmodelallowedtherenewalofnaturalgasturbinesattheendoftheireconomiclife;thesecondassumednorenewalsandrequiredthepermanentretirementofthenaturalgasG-14 turbinesattheendoftheirusefullives.Thispolicyaffects456MWofexistinggasturbineunits.TherationalebehindthesetworenewalpoliciesisrelatedtotheimplementationoftheFuelUseAct(FUA)whichprohibitsthebuildingofnewgeneratingunitsoper-atingonnaturalgas.TheFUAisdiscussedmorefullyinSection6.6whereitwasshownthatRailbeltutilitieswouldprobablyberestrictedtonewgasfacilitiesforpeakingapplicationsonly.Thepolicyofrenewalornon-renewalofgasturbineshasaminimaleffectonlong-termpresentworthcostofthethermalsystemmodel.ThisisclearlyshowninTableG.llwherethepresentworthcostdifferencebetweenthetwopolicies,underamediumloadforecast,isonly$20million.Thenaturalgasturbinespermanentlyretiredareinfactsimplyreplacedbypeaking-onlynaturalgasturbines.Thelong-termpresentworthcostofthethermalgeneratingsystemis$8110millionassuminggasturbinerenewals.Thesame10-yeargenerationplan(for1981-1990)appliestothethermalgeneratingscenarioasitdoesforthehydroelectricscenar-iosgivenabove.ThisperiodseestheinstallationoftheBelugacombinecycleUnitNo.8byChugachElectricAssociationandthe94MWBradleyLakehydroplantin1988.Underthemediumloadforecastthelevelofinstalledcoal-firedunitsincreasesfrom54MWin1990to900MWin2010withthefirstcoalunitadditionin1993tomeetlossofloadprobabilityrequire-ments.Themodelselects100MWcoalunitadditionsover250and500MWunits.ThisselectionisdueinparttoarelativelyslowdemandgrowthfromyeartoyearandthegenerousreservecapacityofpeakingunitsintheexistingRailbeltregion.The2010systemmixiscomprisedprimarilyofnaturalgasturbinesandcoalunits,althoughenergydispatchedismorereliantoncoalplantsoperatingatapproximately70percentplantfactor.(ii)OtherLoadForecastsSection5identifiedloadforecastswhichtookintoaccountcombina-tionsoflevelsofeconomicgrowthandgovernmentexpenditure.Theseloadforecastsalsoincludedthecaseswithloadmanagementandconservationandtheprobabilisticvariationonthemediumloadforecast.Asinthemediumforecast,thetwocasesofgasturbinerenewalornon-renewalweredetermined.HighLoadForecastThehighloadforecastrequirestheinstallationofa100MWcoal~firedplantin1990.ThisisthesameaswasdeterminedforSusitnaandnon-Susitnahydroscenariosunderthehighloadfore-cast.Thelong-termpresentworthcostofthethermalgenerationscenari0underthisloadforecastis$13,630mi11ionassumingarenewalpolicyofgasturbines.Thereisaslightbenefitof$110millionifapolicyofnon-renewalispursued.However,thehlocasescanbeassumedtobeeffectivelythesame.G-15 -LowLoadForecastThelowloadforecastrequiresapproximatelyonethirdofthecapacityadditionsasthehighloadforecast(TableG.11).Thepresentworthcostofthethermalsystemunderthelowloadfore-cast,andassumingrenewalsofgasturbineunits,is$5910million.Withnorenewals,thepresentworthcostisveryslightlyincreasedto$5920million.LoadManagementandConservationForecastThethermalgenerationplanrequiredtomeetthelowloadfore-castwithadeterminedpolicyofloadmanagementandconservationwasdevelopedusingthesameprinciplesandpracticeasfortheSusitnaplans.Aswouldbeexpectedthisforecastresultedinalowercostsystemthanthatfoundundertheunadjustedlowloadforecast.Thepresentworthcostwasfoundtobe$4930millionforthisscenario(norenewalswereassumed).-ProbabilisticLoadForecastTocompletetheanalysisofthethermalgenerationplan,themed-iumloadforecastwasoperatedundertheassumptionofaprob-abilisticloadvariation.Theeffectofassumingthisvariationtothemediumforecastresults,aswasfoundforSusitnaBasindevelopments,inanincreaseinlong-termpresentworthcost.Thepresentworthcostforthissystem(TableG.11)is$8320million.Thisassumesnogasturbinerenewalsandrepresentsanincreaseof$190millionoverthecomparablemediumloadforecastcase.(iii)SensitivityAnalysesItisimportanttoobjectivelydeterminethesensitivityofnon-Susitnaornon-renewalresourcedependentgenerationplansorchangesincostsandescalationoffuel,interestrates,construc-tioncosts,andplantlife.InterestRateSensitivityAsintheSusitnadevelopmentscenarioandtheinvestigationintothesensitivityoftheplantoeconomicparameterchanges,theassumedunderlyingescalationrateforthebasecasethermalplaniszeropercentandtheinterestrateisthreepercent.Sensi-tivityofthethermalplantochangesintheinterestrateto5and9percentwasdetermined,againassumingazeropercentesca-lationorinflationrate.TableG.12showsthechangeofthepresentworthcostfortheplanfrom$8130millionto$5170millionand$2610millionforfiveandninepercentinterestratesrespectively.G-16 IfacomparisonwastobedrawnbetweenthermalandSusitnascen-ariosstudiedunderthesensitivityanalyses,itwouldshowthatthetwoplanswouldbeeconomicallycomparable(intermsofpresentworthcost)ifinterestrateswereapproximatelyeightpercent.Toprovidereasonablecomparisonsbetweeninterestratesensitiv-ityanalysesitwasnecessarytoassumethatthegenerationsystemmixwouldbesimilarasthatdeterminedforthethreeper-centOGP5run.Ifthiswasnotthecase,thenOGP5wouldselectcheapergenerationunits,particularlynaturalgas,whichprob-ablywouldnotmeetdefinedcriteriaonsystemcomponents.-FuelCostThereductionoffuelcostsby20percentproducessignificantreductioninpresentworthcostofapproximately$1060millionto$7070million.Thisreductionisduetothelowerexpenseofsupplyingtheplantswiththenecessaryfueltopowertheunits.-FuelCostEscalationFuelcostescalationsensitivitywasassessedintwomethods.Thefirstwasassumingzeropercentescalationforallthreemajorfuelsandthesecondwastoassumezeropercentforcoalonly,withoilandnaturalgasremainingatanescalationrateof3.58and3.98percentrespectively.Inbothcasesescalationrateswereassumedtoapplybetween1980and2005andprogress-ivelydroppingtozeroin2010.Thecaseofzeropercentescalationforallfuelsshowsadra-maticreductioninpresentworthcostof$3570millionoverthebasecasethermalscenario(TableG.12).Aswouldbeexpectedforzeropercentescalationinthecostofcoal,thereductioninproductioncostislessthanfornoesca-lationincostofanyfuel.Thisreductionis,however,stillsignificantandamountstoanannualsavingsof$1210millionoverthebasecasethermalplan.-EconomicLifeofThermalPlantTheuncertaintyassociatedwiththeprobableplantlifeofin-stallationsintheRailbeltregionnaturallyraisesconcerns.Toaddresstheseconcernsthethermalplantlife,ineachcategory,wasextendedby50percent.Theplantlifethereforebecame45,45,and30yearsforcoal,gasandoilfacilitiesrespectively.Theextensionoftheeconomicliferesultsinagainincostofapproximately$280millionforthethermalgenerationscenario.G-17 -ThermalCapitalCostsCapitalcostisanotherareaofconcernwhichhasbeenaddressedinanattempttonegotiatetheuncertaintiesassociatedwithcostingworkorstructuresinremoteareas.Althoughthecostsdevelopedarebelievedtobethebestpossibleestimatesthatcanbemadeatthistime,thecostsofall-thermalplanttypeshavebeenreducedby22percent.Aswouldbeexpectedfromalogicalinspectionatthesystem,thereductionincoalplantcostsresultsincoalbecomingmoreeco-nomicallyviableasanenergyscource.Capitalcostsreductionthereforeshowsagainincoalcapacitygenerationof200MWoverthebasecasethermalplan.Thelongtermpresentworthcostisreducedto$7590million,areductionof$540millionfromthebasecase.G-18 TABLE G.1 -SALIENT fEATURES Of GENERATION PLANNING PROGRAMS Programl Load Generat ion ----------opt 1m lzat ion--Reltability Pf-o-difcElon Av8i1-aoiIlty and Developer Modeling Modeling Available Criterion Simulation Cost/Run GENOP/Done by two Done by one yes LOLP or Deterministic or $500 to validate Westinghouse external external %reserve Modified Booth -Learning Curve programs program Baleriaux Costs $300 -$BOO/run PROMOD/EMA Done by one Done by one no LOLP or Modified Booth -$2,500 to validate external external %reserve Baleriaux on TYMSHARE program program learning Curve Costs $300 -$500/run OGP/GE I)one by one Dane by one yes LDLP or Deterministic or AAI validated external external %reserve Stochastic Columbia &Buffalo program program Experienced Personnel $50 -$BOO/run TABLEG.2-RAILBELTREGIONLOADANDENERGYfDRECASTSUSEDfORGENERATIONPLANNINGSTUDIESLOADCASELowPlusLoadManagementandLowMediumHighConservation(LES-GL)2(MES-GM)3(HES-GH)4(LES-GLAdjusted)1loadLoadloadload~MWGWhFactorMWGWhFactorMWGWhfactorMWGWhFactor198D510279062.551D279062.4510279062.4510279062.419B5560309062.858D316D62.4650357062.66953B6063.4199062D343063.2640350562.4735403062.6920509063.119956B5381D63.5795435062.3945517062.51295712062.82000755424063.8950521062.31175643D62.41670917062.62005835469064.11045570062.21380753062.3228512540'62.62010920520064.41140622D62.21635894062.4290D1593062.7~:(1)LES-GLLoweconomicgrowth/lowgovernmentexpenditurewithloadmanagementandconservation.(2)LES-GLLoweconomicgrowth/lowgovernmentexpenditure.0)MES-GMMediumeconomicgrowth/moderategovernmentexpenditure.(4)HES-GHHigheconomicgrowthlhighgovernmentexpenditure. TABLEG.'-LOADSANDPROBABILITIESUSEDINGENERATIONPLANNINGNotes:FORECAST1PROBABILITYSETLES-LG.10LES-MG.20MES-MG.40HES-MG.20HES-HG.10LoweconomicgrowthmediumeconomicgrowthhigheconomicgrowthlowgovernmentexpendituremoderategovernmentexpenditurehighgovernmentexpenditureLES:MES:HES:LG:MG:HG:(1) TA8lEG.4-fUELCOSTSANOESCALATIONRATESNaturalGascoalD~stI1IateBasePeriod(January1980)-Prices($/million8tu)MarketPrices$1.05$1.15$4.00Shadow(Qpportunity)Values2.001.154.00RealEscalationRates(Percentage)-ChangeCompounded(Annually)1980-19851.79%9.56%3.38%1986-19906.202.393.091991-19953.99-2.874.27Composite(average)1980-19953.982.933.581996-20053.982.933.582006-2010000 TABLEG.5-ANNUALFIXEDCARRYINGCHARGESUSEDINGENERATIDNPLANNINGMDDELProjectL1feJlype3d-Year3S-Year50-Year20-YearThermal ThermalHydroThermal(%)(%)(%)(%)ECDNOMICPARAMETERS(0%-3%)CostofMoney3.0D3.DO3.00 3.00Amortization2.1D1.650.893.72Insurance0.250.25 0.100.25TOTALS>.J)4.'9IT~b.97FINANCIALPARAMETERS(7%-10%)Non-exemptCostoffoklney10.DO10.00 10.0010.00Amortization0.610.370.091.75Insurance0.250.250.10 0.25TOTALSm:m-l'IJ:b'2"TO:T9"n:mrTax-exemptCostofMoney8.00 8.00 8.00 8.00Amortization0.880.580.172.19Insurance0.25 0.25 0.100.25TOTALS'1:'UF.lITe.rrlu:44 TABLEG.6-TENYEARBASEGENERATIONPLANMEDIUMLOADfORECASTSYSIEM(AwlToTALYEARMWMWNGOILoILCAPABILITYCommittedRetiredCOALGTGTDIESELCCHY(MW)19BO544701686514149947119B1544701686514149947198260CC54.470168652014910071983544701686520149100719845447016865201491007198514(NGGT)544561686520149993198650456168652014999319874(Coal)504561686520149989198895HY5045616865201144108419895(Coal)45456168652011441079199045456168652011441079Notes:(1)Thisfiguresvariesslightlyfromthe943.6MWreportedduetointernalcomputerrounding. TA8LE G.7 -SUSITNA ENVIRONMENTAL DEVELOPMENT PLANS Cwnulatlve Stage/Incremental Data System Data Annual Maximum Energy Capital Cost Earliest Reservoir Seasonal Production Plant $Millions On-I ina full Supply Draw-Firm Avg.Factor (1980 values)1 ~Plan Stage Construction Dete Level -ft.down-ft GWH GWH.~ E1.1 1 Watana 2225 ft 800MW and Re-Regulation Dam 1960 1993 2200 150 2670 3250 46 2 Devil Canyon 1470 ft 400MW 900 1996 1450 100 5520 6070 58 TOTAL SYSTEM 120~IW '2llbll" E1.2 1 Watan'2060 ft 400MW 1570 1992 2000 100 1710 2110 60 2 Watana raise to 2225 ft 360 1995 2200 150 2670 2990 85 3 Hat ana add 400MW capacity and Re-Regulation Dam 230 2 1995 2200 150 2670 3250 46 4 Devil Canyon 1470 ft 400MW 900 1996 1450 100 5520 6070 58 TOTAL SYSTEM 1200MW 1ll61l" E1.3 1 Watana 2225 ft 400MW 1740 1993 2200 150 2670 2990 85 2 Hat ana add 400MW capacity and Re-Regulation Dam 250 1993 2200 150 2670 3250 46 3 Devil Canyon 1470 ft 400 flH 900 1996 1450 100 5520 6070 58 TOTAL SYSTEI1 1200MW 2ll"9lf TABLE G.7 (Continued) Cumulative Stage/Incremental Data System Data Annual Maximum Energy Cap ital Cost Earliest Reservoir Seasonal Production Plant $Millions On-line full Supply Draw-firm Avg.factor (1980 values)1PlanStageConstructionDate Level -ft.down-ft.GWH GWH ~ E1.4 1 Watana 2225 ft 4DOMW 1740 1993 2200 150 2670 2990 85 2 Devil Canyon 1470 ft 400MW 900 1996 1450 100 5190 5670 81 TOTAL SYSTEM 800MW 2640 EZ.1 1 High Devil Canyon 1775 ft 800MW and Re-Regulation Dam 1600 1994 3 1750 150 2460 3400 49 2 Vee 2350ft 400MW 1060 1997 2330 150 3870 4910 47 TOTAL SYSTEM 1200MW 266ii E2.2 1 High Devil Canyon 1630 ft 400MW 1140 1993 3 1610 100 1770 2020 58 2 High Devil Canyon raise dam to 177S ft add 400MW and Re-Regulation Dam 600 1996 1750 150 2460 3400 49 3 Vee 2350 ft 400 MW 1060 1997 2330 150 3870 4910 47 TOTAL SYSTEM 1200MW 2800 E2.3 1 High Devil Canyon 1775 ft 400MW 1390 1994 3 1750 150 2400 2760 79 2 High Devil Canyon add 40~lW capacity and Re-Regulation Dam 240 1995 1750 150 2460 3400 49 3 Vee 2350 ft 400MW 1060 ,.997 2330 150 3870 4910 47 TOTAL SYSTEM 1200 2690 cumulatIve Stage/Incremental Data System Data Annual Maximum Energy Capital Cost Earliest Reservoir Seasonal Production Plant $Millions On-line Full Supply Draw-Firm Avg.Factor (1980 values)1Plan.Stage Construction Date Level -ft.down-ft.GWH GWH ~ E2.4 1 High Devil Canyon 17 55 ft 40()1W 1390 1994 3 1750 150 2400 2760 79 2 High Devil Canyon add 400MW capacity and Portage Creek Dam 150 ft 790 1995 1750 150 3170 4080 49 3 Vee 2350 ft 40()1W 1060 1997 2330 150 4430 5540 47 TOTAL SYSTEM mrr EJ.2 1 Watana 2225 ft 40()1W 1740 1993 2200 150 2670 2990 85 2 Watana add 400 MW capacity and Re-Regulat ion Dam 250 1994 2200 150 2670 3250 46 3 Watana add 5()1W Tunnel Scheme 330MW 1500 1995 1475 4 4890 5430 53 TOTAL SYSTEM 118(}IW ~ E4.1 1 Watana 2225 fL 40()1W 1740 1995 3 2200 150 2670 2990 85 2 Watana add 40()1W capacity and Re-Regulation Dam 250 1996 2200 150 2670 3250 46 3 High Devil Canyon 1470 ft 40()1W 860 1998 1450 100 4520 5280 50 4 Portage Creek 1030 ft 15()1W 650 2000 1020 50 5110 6000 51 TOTAL SYSrEM 1350 MW J'5Ulr NOTES: ("f)-Allowing for a 3 year overlap construction period between major dams. (2)Plan 1.2 Stage 3 is less expensive than Plan 1.3 Stage 2 due to lower mobilization costs. (3)Assumes FERC license can be filed by June 1984,ie.2 years later than for the Watana/Oevil Canyon Plan 1. TABLE G.B -RESULTS Of ECONOMIC ANALYSES Of SUSITNA PLANS -MEDIUM LOAD fORECAST Sus~tna Develo~nt Plan Inc.Installed CapacIty (Aw)by total System fetal System [},lne Dates Category in 2010 Installed Present Remarks Pertaining to Plan Stages OGP5 Run Thermal Hydro Capacity In Worth Cos~the Susitna Basin No.T 2 3 4 Id.No.Coal Gas 01.1 Other Susltna 2010-MW $Mill ion Development Plan El.1 1993 2000 ----LXE7 300 426 0 144 1200 2070 5B50 E1.2 1992 1995 1997 2002 L5Y9 200 501 0 144 1200 2045 6030 E1.3 1993 1996 2000 --LBJ9 300 426 0 144 1200 2070 5B50 1993 1996 ----L7W7 500 651 0 144 BOO 2095 6960 Stage 3,Devil Canyon Dam not constructed 199B 2001 2005 --LAD7 400 276 30 144 1200 2050 6070 Delayed implementation schedule E1.4 1993 2000 ----LCK5 200 726 50 144 BOO 1920 5B90 Total development limited to BOO MW flJdified E2.1 1994 2000 ----LA25 400 651 60 144 BOO 2055 6620 High Devil Canyon limited to 400 MW E2.3 1 1993 1 9 9 6 2000 --L601 300 651 20 144 1200 2315 6370 1993 1996 ----LE07 500 651 30 144 BOO 2125 6720 Stage 3,Vee Dam,not constructed Modified EZ.3 1993 1 9 9 6 2000 LEB3 300 726 220 144 1300 2690 6210 Vee dam replaced by Chakachamna dam 3.1 1993 1996 2000 --L607 200 651 30 144 IlBO 2205 6530 Special 3.1 1993 1996 2000 --L615 200 651 30 144 IlBO 2205 6230 Capital cost of tunnel reduced by 50 percent E4.1 1995 1996 199B --LTZ5 200 576 30 144 1200 2150 6050 Stage 4 not constructed ~: (1)Adjusted to incorporate cost of re-regulation dam Remarks Plan Stages OGP5 Run Thermal Hydro Capacity In Worth Cost the Susitna Basin No.1 Z 3 4 Id.No.Coal Gas 011 Other Sus1tna 2010-MW $Million Development Plan VERY LOW FORECAST 1 E1.4 1997 2005 ----L7B7 0 651 50 144 BOO 1645 3650 LOW LOAD FORECAST E1.3 1993 1996 2000 ------------------low energy demand does not warrant plan capacities E1.4 1993 2002 ----LC07 0 351 40 144 BOO 1335 4350 1993 ------LAK7 200 501 BO 144 400 1325 4940 St age 2,Dev il Canyon Dam, not constructed E2.1 1993 2002 ----LG09 100 426 30 144 BOO 1500 4560 High Devil Canyon limited to 400 MW 1993 -- -- --LBUl 400 501 0 144 400 1445 4B50 Stage 2,Vee Dam,not constructed E2.3 1993 1996 2000 -------------------low energy demand does not warrant plan capacities Spec ial 3.1 1993 1996 2000 --L613 0 576 20 144 780 1520 4730 Capital cost of tunnel reduced by SO percent 3.2 1993 2002 ----L609 0 576 20 144 7BO 1520 5000 Stage 2,400 MW addition to Watana,not constructed HIGH LOAO FORECAST E1.3 1993 1996 2000 --LA73 1000 951 0 144 1200 3295 106BO Modified 2005 2E1.3 1993 1996 2000 LBV7 BOO 651 60 144 1700 3355 10050 Chakachamna hydroelectric generating station (4BO MW) brought on line as a fourth stage E2.3 1993 1996 2000 --LBV3 1300 951 90 144 1200 36B5 11720 Modified 2003 2E2.3 1993 1996 2000 LAYl 1000 876 10 144 1700 3730 11040 Chakachamna hydroelectric generating ststion (480 MW) brought on line as a fourth stage NOTE: (1)Incorporating load management and conservation TABLE G.10 -RESULTS OF ECONOMIC SENSITIVITY ANALYSES FOR GENERATION SCENARIO INCORPORATING SUSITNA BASIN DEVELOPMENT PLAN E1.3 -MEDIUM FORECAST Total Total Installed Capacity (MW)by System System Installed Present Category in 2010 Capacity Wodh Description Parameter OGP5 Run Thermal Hydro In 2010 Cost Parameter Varted Values Id.No.coal Gas OIl OEher Sus1tna MW $Million Remarks Interest Rate 5%LFB5 300 426 0 144 1200 207D 4230 9%LFB7 300 426 D 144 1200 2070 2690 Fuel Cost ($million Btu, natural gas/coal/oil)1.60/0.92/3.20 L533 100 576 20 144 1200 2040 5260 20%fuel cost reduction Fuel Cost Escalalion (%, natural gas/coal/oil)0/0/0 L557 0 651 30 144 1200 2025 4360 Zero escalation 3.98/0/3.58 L563 300 426 0 144 1200 2070 5590 Zero coal cost escalation Economic life of Thermal Plants (year,natural gas/coal/oil)45/45/30 L585 45 367 233 144 1200 19B9 610D Economic lives increased by 50% Thermal Plant Capital Cost ($/kW,natural gas/ coal/oil)350/2135/77B LEIl7 300 426 0 144 1200 2070 5740 Coal capital cost reduced by 22?o \1atan~/Devil Canyon Capital Cost ($million,Walana/ Dev il Canyon)1990/1110 L,Gl 300 426 0 144 1200 2070 6210 Capital cost for nevil Canyon Dam increased by 23% 2976/13,0 LD7,300 426 0 144 1200 2070 6B10 Capital cost for both dams increased by 50% Probabilistic Load Forecasl L8T,200 1476 140 144 1200 3160 6290 -- ~: (1)Alaskan cost adjustment faclor reduced from 1.8 to 1.4 (see Section B._) (2)Excluding AFOC TABLE G.11 -RESULTS OF ECONOMIC ANALYSES OF ALTERNATIYE GENERATION SCENARIOS Installed Capacity (MW)by Total System lotal System Category in 2010 Installed Present Worth Generation Scenario OGP5 Run 1herms!Aydro Capacity in Cost - Iype Descriplion Load forecast Id.No.Coal Gas 011 2010 (MW)($10 6 ) All Thermal No Renewals Very Low 1 LAT7 500 426 90 144 1160 4930 No Renewals Low L7El 700 300 40 144 1385 5920 With Renewals Low L2C7 600 657 30 144 1431 5910 No Renewals t-ledilJll LME1 900 801 50 144 1895 8130 With Renewals Medium U1E3 900 807 40 144 1891 8110 No Renewals High L7F7 2000 1176 50 144 3370 13520 With Renewals High L2E9 2000 576 130 144 3306 13630 No Renewals Probabilistic LOF3 1100 1176 100 144 3120 8320 Thermal Plus No Renewals Plus:Medium L7W1 600 576 70 764 2010 7080 Alternative Chakachamna (500)2_1993 Hydro KeeLna (120)-1997 No Renewals Plus:Medium LFL7 700 501 10 814 2025 7040 Chakachamna (500)-1993 Keetna (120)-1997 Snow (50)-2002 No Renewals Plus:"led tum LWP7 500 576 60 847 1983 7064 Chakachamna (500)-1993 Keetna (120)-1996 Strandline (20), Allison Creek (8), Snow (50)-1998 No Renewals Plus:Medium LXf1 700 426 30 847 2003 7041 Chakachamna (500)-1993 Keetna (120)-1996 Strandline (20), Allison Creek (8), Snow (50)-2002 No Renewals Plus:Med il.ltl L403 500 576 30 947 2053 7088 01akachamna (500)-1993 Keetna (120)-1996 Snow (50),Cache (50), Allison Creek (8), Talkeetna-2 (50), Strandline (20)-2002 Notes: (1)Incorporating load management and conservation (2)InsLalled capacity TABLE G.12 -RESULTS OF ECONOMIC ANALYSES FOR GENERATION SCENARIO INCORPORATING THERMAL DEVELOPMENT PLAN -MEDIUM FORECAST lotal System lota1 Installed Capacity (MW)Installed System by Category in 2010 Capacity Present Description Parameter OGP5 Run Thermal In 2010 Worth Cost Parameter varled Value Id.No.Coal Gas ulI Hydro Total MW $Million Remarks Interest Rate 5%LEA9 900 BOO 50 144 1895 5170 9%LEBl 900 801 50 144 1895 2610 Fuel Cost ($million Btu, natural gas/coal/oil)1.60/0.92/3.20 L1K7 800 876 70 144 1890 7070 20%fuel cost reduction fuel Cost Escalation (%, natural gas/coal/oil)0/0/0 L547 0 1701 10 144 1855 4560 Zero escalation 3.98/0/3.58 L561 1100 726 10 144 1980 6920 Zero coal cost escalation Economic Life of Thermal Plants (year)natural gas/coal/oil 45/45/30 L583 1145 667 51 144 2007 7850 Economic life increased 50% Thermal Plant Capital Cost ($/kW,natural gas/350/2135/778 LAL9 1100 726 10 144 1980 7590 Coal capital cost reduced coal/oil)by 22% 220102005IIIIIIIIIIIIIIIHES-GHIIII------LES-GLADJUSTED20001995YEARIIFIGUREG.I,,,,,,//"/,,/,//,19901985HES-GH,HIGHECONOMICGROWTHTHIGHGOVERNMENTEXPENDITUREMES-GM'MODERATEECONOMICGROWTHTMODERATEGOVERNMENTEXPENDITURELES-GL'LOWECONOMICGROWTHTLOWGOVERNMENTEXPE~DITURELES-GLADJUSTED'LOWECONOMICGROWTHTLOWGOVERNMENTEXPENDITURETLOADMANAGEMENTANDCONSERVATIONLEGEND0'----.1.-'--'-'----.1.....1980ENERGYFORECASTSUSEDFORGENERATIONPLANNINGSTUDIES1615141312II~:I:;;:10(,!)~z09~a::wz8W(,!)>-f-()7ii::f-()W6...JW54 PPENDIXH-ENGINEERINGSTUDIESAstheprojectplanningstudiesoutlinedinSections6and7werecompleted,astartwasmadewithmoredetailedengineeringstudiesfortheselectedWatanaandDevilCanyonsites.Themajorthrustofthesestudieswastwofold:-Toselecttheappropriatedamtypeforthetwosites;-Toundertakesomepreliminarydesignoftheselecteddamtypes.Thissectionbrieflyoutlinestheresultsofthestudiestodate.AmoredetaileddescriptionwillbeincorporatedintheProjectFeasibilityReport.-DevilCanyonSiteDamTypeStudiesAmajoradvantageofanarchdamrelativetoacomparablerock/earthfillstructureisthegenerallylowercostoftheauxiliarystructures,whichcanbeincorporatedwithinthedamitselforreducedinoveralllengthcorrespondingtothereducedbasewidthoftheconcretedam.Inordertostudytherelativeeconomicsofdifferentdamtypesitwasnecessarytodevelopgeneralarrangementsofthesitesincludingthediversion,powerfacilitiesandspillways.ArepresentativearrangementwasstudiedforeachofthefollowingdamtypesattheDevilCanyonsite:- Athickconcretearchdar,];- Athinconcretearchdam;and- Arockfilldam.Noneoftheselayoutsareintendedasthefinalsitearrangement,buteachwillbesufficientlyrepresentativeofthemostsuitablearrangementasso-ciatedwitheachdamtypetoprovideanadequatebasisforcomparison.EachtypeofdamislocatedjustdownstreamofwheretheriverentersDevilCanyon,closetothecanyon'snarrowestpoint,whichistheoptimumloca-tionforalltypesofdams.Abriefdescriptionofeachdamtypeandcon-figurationisgivenbelow.(i)ThickArchDamAsshownonPlatesH.IandH.2,themainconcretedamisasinglecenterarchstructure,actingpartlyasagravitydarn,withaverticalcylindricalupstreamfaceandaslopingdownstreamfaceinclinedat1V:D.4H.Themaximumheightofthedamis635feetwithauniformcrestwidthof30feet,acrestlengthofapproximately1400feetandamaximumfoundationwidthof225feet.Thecrestelevationis1460feet.Thecenterportionofthedamisfoundedonamassiveconcretepadconstructedintheexcavatedriverbed.Thiscentralsectionincorporatesaservicespillwaywithgatedorificespillwaysdischarg-ingdownthesteeplyinclineddownstreamfaceofthedamintoasinglelargestillingbasinwithsidewallsanchoredintosolidbedrocksetbelowriverlevel,spanningthevalley.H-l Themaindamterminatesinthrustblockshighontheabutments.Theleftabutmentthrustblockincorporatesanemergencygatedcontrolspillwaystructurewhichdischargesintoarockchannelrunningwelldownstreamandterminatingatahighlevelintherivervalley.Beyondthecontrolstructureandthrustblockalowlyingsaddleontheleftabutmentisclosedbymeansofarockfilldikefoundedonbedrock.Thepowerhousehousesfour150MWunitsandislocatedundergroundwithintherightabutment.Themulti-levelintakeisconstructedintegrallywiththedamandconnectedtothepowerhousebyverticalsteel-linedpenstocks.Theservicespillwayisdesignedtopassthe1:10,000yearroutedfloodwithlargerfloodsdischargeddownstreamviatheemergencyspi11way•(ii)ThinArchDamAsshownonPlate10,themaindamisatwo-center,doublecurvedarchstructureofsimilarheighttothethickarchdam,butwitha20footuniformcrestwidthandamaximumbasewidthof90feet.Thecrestelevationis1460feet.Thecentersectionisfoundedonaconcretepadandtheextremeupperportionofthedamterminatesinconcretethrustblockslocatedontheabutments.Themainservicespillwayislocatedontherightabutmentandconsistsofaconventionalgatedcontrolstructuredischargingdownaconcrete-linedchuteterminatinginaflipbucket.Thebucketdischargesintoanunlinedplungepoolexcavatedintheriverbedalluviumandlocatedsufficientlydownstreamtopreventunderminingofthedamandassociatedstructures.Themainspillwayissupplementedbyorificetypespillwayslocatedhighinthecenterportionofthedamwhichdischargeintoaconcrete-linedplungepoolimmediatelydownstreamofthedam.Anemergencyspillwayconsistingofafuseplugdischargingintoanunlinedrockchannelwhichterminateswelldownstream,islocatedbeyondthesaddledamonthe1eftabutment.Theconcretedamterminatesinamassivethrustblockoneachabutmentwhich,ontheleftabutment,adjoinsarockfillsaddledarn.Theserviceandauxiliaryspi11way'saredesignedtodischargethe1:10,000yearflood.Excessflowsforstormsuptotheprobablemaximumfloodwi11bedischargedthroughtheemergency1eftabutmentspillway.(iii)RockfillDamAsshownonPlate1,therockfilldamisapproximately670feethigh.Ithasacrestwidthof50feet,upstreamanddownstreamslopesof1:2.25and1:2respectively,andcontainsapproximately20millionH-2 cubicyardsofmaterial.Thecentralimperviouscoreissupportedbyadownstreamsemi-perviouszone.Thesetwozonesareprotectedup-streamanddownstreambyfilterandtransitionmaterials.Theshellsectionsareconstructedfromblastedrock.Alldamsectionsarefoundedonsoundbedrock.Externalcofferdamsarefoundedontheriverbedalluvium.Asinglespillwayconsistingofagatedcontrolstructure,chuteanddownstreamunlinedplungepoolislocatedontherightabutment.Thisisdesignedtopasswithoutdamagethe1:10,000yearroutedflood.Excesscapacityisprovidedtoallowdischargeoftheprobablemaximumfloodwithnodamagetothemaindam.ConstructionMaterialsSandandgravelforconcreteaggregatesarebelievedtobeavailableinsufficientquantitiesimmediatelyupstreamintheCheechakofanandter-races.Thegravel~ndsandsareformedfromthegraniticandmetamorphicrocksofthearea,andatthistimeitisanticipatedthattheywillbesuitablefortheproductionofaggregatesafteramoderateamountofscreeningandwashing.Materialfortherockfilldamshellwouldbeblastedrock,someofitcomingfromthesiteexcavations.Itisanticipatedthatsomeimperviousmaterialforthecoreisavailablefromthetilldepositsformingtheflatelevatedareasontheleftabutmentandthatothersuitableborrowmaterialswillbeavailableinhighlyingareaswithinthethreemileupstreamreachoftheriver;however,noneofthesedepositshaveyetbeenproven.GeneralConsiderationsThegeologyofthesiteisasdiscussedinSection7anditappearsatthisstagethattherearenogeologicalorgeotechnicalconcernsthatwouldpre-cludeanyofthedamtypesfromconsideration.Arockfilldamwouldbemoreadaptablethanaconcretearchdamtopoorerfoundationconditionsalthough,atpresent,foundationandabutmentloadingsfromthearchdamsappearwellwithinacceptablelimits.Thethickarchdamallowsfortheincorporationofamainservicespillwaychuteonthedownstreamfaceofthedamwhichdischargesintoaspillwaylocateddeepwithinthepresentriverbed.Thisspillwaycanpassroutedfloodswithareturnfrequencyoflessthan1:10,000years.Forthethinarchandrockfillalternativestheequivalentdischargecapacityhastobeprovidedseparatelythroughtheabutments.Stressesunderhydrostaticandtemperatureloadingswithinthethickarchdamaregenerallylowerthanthoseforthethinarchalternative.However,finiteelementanalysishasshownthattheadditionalmassofthedamunderseismicloadingproducesstressesofagreatermagnitudeint~lethickarchdamthaninthethinarchdam.Ifthesurfacestressesapproachthemaximumallowableataparticularsection,theremainingunderstressedareaofconcreteisgreaterforthethickarchandthefactorofsafetyfortheH-3 damiscorrespondinglyhigher.Thethinarchis,however,amoreefficientdesignandbetterutilizestheinherentpropertiesoftheconcrete.Itisdesignedaroundacceptablepredeterminedfactorsofsafetyandrequiresamuchsmallervolumeofconcretefortheactualdamstructure.Atthetimeofcompletionoflayoutsindicationswerethatthethinarchdamwouldbefeasible.Athickarchdamlayoutwascompletedtodetermineifitprovidedanyoutstandingadvantages,andincaseathinarch,inspiteofindications,shouldproveinfeasible.Itdidnotappeartohaveanyoutstandingmeritscomparedtoathinarchdamandwouldbemoreexpensiveduetothelargervolumeofconcrete.Arockfilldamconstructedtothedesigncurrentlyassumedoffersnocostsavingsrelativetothethinarchconsiderationofmoreconservativedesignsinwhichtheupstreamrockfillslopesarerevisedfrom1:2.25to1:2.75tomeetpossiblymorestringentseismicdesignrequirements.Thesecostincreaseswouldoccurinthedamitselfandinspillwayandpowerfacilitiesbecauseofthelargerbasewidthofthedam.Studieshavethereforecontinuedinanefforttoconfirmthefeasibilityofthethinarchalternative.(d)PreliminaryArchDamDesignBoththinandthickarchdamdesignswereoriginallyanalyzedbymeansofacomputerprogrambasedonfiniteelementanalysis.Resultsfromtheseanalysesindicatedsignificantlylowerstressesforthethickarchunderhydrostaticandtemperatureloadings,aswouldbeanticipated.Substan-tiallyhighertensilestresseswerefoundunderseismicloadingconditionsforbothdams,althoughsomewhathigherinthecaseofthethickarchdarn.Stressesclosetothefoundationsandabutmentsweredistortedbythefiniteelementmodelbecauseofthecoarsemeshspacingoftheselectednodes.Toproduceresultswhichcouldmorereadilybeinterpreted,itwasdecidedtousethetrialloadmethodandtheassociatedprogramArchDamStressAnalysisSystem(ADSAS)developedbytheUSBR.Theresultsofthisanalysisarepresentedinthefollowingparagraphs.Thethin,two-centerarchdamdesignislocatedapproximatelynormaltothevalley.Thereisagradualthickeningofthedamtowardstheabutments,butthetwo-centerconfigurationproducessimilarthicknessandcontactpressuresatequivalentrock/concretecontactelevationsandasymmetricaldistributionofpressuresacrossthedam.Underhydrostaticloadsnoten-sionisevidentatthedamfaces.UnderextremetemperaturedistributionasdeterminedbytheUSBRprogramHEATFLOvJ,fullreservoirconditionsbringaboutlowtensilestressesonbothfacesacrossthecrestofthedam.Theseapproachtheallowabletensilestressof150psi.Althoughanalysishasstilltobefinalizedforseismicloadings,indica-tionsarethattheconcretethinarchdamatDevilCanyonwillbestructurallyfeasible.H-4 2 -WatanaSiteDamTypeStudiesArockfilldamlayout(Plate12)hasbeenstudiedatWatanawiththedamsitedbetweenthenorthwesttrendingshearzonesofthe"Fins"andthe"Fingerbuster".ThedamisclosetothealignmentproposedbytheCorpsofEngineersandisskewedslightlytothevalleyinanorth-northwestdirection.Theapproximateheightofthedamis900feet,theupstreamanddownstreamslopesare1V:2.75Hand1V:2Hrespectively,andthevolumeisapproximately62millioncubicyards.Theassumedcrestelevationofthedamis2225feet,subjecttocompletionofreservoirleveloptimizationstudies.Forinitialstudypurposes,thespillwayhasbeenassumedtodischargedowntherightabutmentwithanintermediatestillingbasinandadownstreamstillingbasinfoundedbelowriverlevel.Two35feetdiameterdiversiontunnelsarelocatedontherightbankandan800MWundergroundpowerstationislocatedontheleftabutment.Optimizationstudiesofspillway,diversionandpowerplantfacilitiesarecontinuing.ConstructionMaterialsAtthistimeitisassumedthat50percentoftherockfillfortheshellmaterialforthedamwillbeblastedrock,asmallproportionofwhichwillbeobtainedfromsiteexcavations;theremainderwillconsistofblastedrockfromborrowareas.Theremaining50percentwillbegravelmaterialsobtainedfromthedownstreamalluvialriverbeddeposits.GravelsforfilterzonesareavailablefromalluvialdepositsinTsusenaCreek.Corematerialisavailabdefromglacialtillslocatedapproximatelythreemilesupstreamabovetherightsideoftherivervalley.Thismaterialwillrequireverylittleprocessing.)GeneralConsiderationsAsanalternativetotherockfilldam,athree-centerconcretethinarchhasbeenconsidered,andlayoutsareshownonPlatesH.3andH.4.Thevolumeofthedamis8.25millioncubicyardswithadditionalconcreterequiredfortheabutmentthrustblocks.Theoverallcostofconcretewillbeapproximately$1,300millionascomparedto$950millionfortheupperlimitcostestimateforfillwithintherockfilldam.Althoughwaterpassageswillbeshorterforfacilitiesassociatedwiththeconcretedam,itisanticipatedthatthesewillbeoffsetbysavingsinthespillwayexcavationassociatedwiththerockfilldamwhereexcavatedmaterialcanbeutilizedwithinthedam.TheoverallcostsforbothtypesofdamandtheirassociatedfacilitieswillbeevaluatedfurtherintheProjectFeasibilityReport.Inthemeantime,studyoflayoutsassociatedwiththerockfilldamhasproceeded.PreliminaryDamDesignAsectionhasbeententativelyestablishedforarockfilldamwithanearverticalimperviouscore(Plate12).Atthistime,nostabilityanalyseshavebeenconductedonthedam,butthesectionisconservativelybasedonH-5 Acres'pastexperienceandongeneralexperiencethroughouttheworldconcerningsimilardamsizesandlocationsofsimilarseismicactivity.Thereisapossibilitythatfurtheranalysiswillleadtoareduction.insizeofthedam.Thecrestwidthofthedamis80feet,theupstreamslopeisIV:2.75HandthedownstreamslopeisIV:2H.Thecoreiscomposedofmaterialsfromthefinetilldepositsandtheshellispresentlytobeconstructedofblastedrockfromsiteexcavationsandfromborrowandgravelmaterialtakenfromtheriverbed.H-6 ,CENTR"L.ANGLA(DECO.)'»Sq"JJ)5KARESOURC·UHR~R~USDart:roent0theInteriOr.,ep/PLATEHIL-/DEvlLCANYONARCHGI<AVITYDAMSCHEMEPLANANDSE.CTIONSRI~-440'R"&20'RI·40o!'RI,,_~OOIk'I..51400'/,~.--,--,~CH.APP.APPj\""............'-xREVISIONSAR.C~·GRAVITYDAMGEOME.TRY\~"S'E.I~:"IC.E.SPILL.WA'(-OR-PICE.'20'·0.'ZO'-ODOWN~IRE.AME.LEVATIONOFDAM----\\t--2'RC!;,,'-".~'"~"'~O~'----"-------...Jl!IOj•IRWL.EL.14'50~~-"':~~~:-&-S-_~IO.",~o'------.-J~.500I~OI-1200IIIIIIL~Z11000~":>III1000JIII900.!I20200'·0GROUT.c,uIllTAIN·eoTTOMciNEI~OORIGHT~ANtLTt-I~U$TP-tLOCl(,1506-1400I!>GO.+1'7.~"'~t-III1100-IIIlL~1000Z0I-4"100>IIIJIII600100-·~-500-.~I/JrOO-------..~0g(f"-uJoARRANGEMENTGENERAL/II1~/'/...uJ//'/~\,0°-HQUS:Bl..OCI(."'1--,'fJfNING,.//I/00::>/I/,,_/I,'-,._\",00./\1!>15JI/J//~/,rv"O/-'til'J~:JI::;//I//~J:>,<9~/'<Jl/I\,I....')/J/IA-I<)I~Ill!II-<f)a.::>'\J\\\\\"\/Fl-OW\\/r\" "-SERvIC.e.5PlLLNAyUt-JITOPF=T1t-JGGIOtOUNDSURFACE.CONcRE.TELlt-JI"'G-'21Tf.·fJoC..POWE.RFACILITIESPi<OFILE.STEE.1..L1t-JE.RCOUPLING_~-~/'IJI------'''-II:,;;:'/'~_~ORIGINAI..-~""-LNORMAI..MA>C..w:L.E.L1450'EL..14SS·IZ>OO-800-900-I-uJWlL~''200-Zoi=1100-~<?OW'NST~CO",.u.o.........(TOBE~VE.O)/CONSOLIC)O.'TIO....GR.OUTING-""RELIEFDQ.AI"'lS·4':;>,A..g~oc/cO~VE.RSIONOLJTLE,TS,0'.10'EL.1'2.&0'-Ai:iiAT1DNOFFSE.T--GQOUTC.uRi.to.INEL.1._~·IO',GO'PLATEH21..ALASKAPOWERAUTHORITYSUSITNAHVDROELECTRICPROJECT~'YORIGINAl..GQOUt-JO5URFA,GI>},./STOPLOGGUIDESDEVILCANYONARGI-lGRAVITYDAMSC~EME5E.CTIONS~""-QJ,"~-­I/"-,'"\ROCK.eeL-,S/SE.CTION5-5----_<000'APPl<OX.........r------~.CONSOLIDATION]GROUTINGRELIE.FOQ.AI"'lS-4"OIA.AEVISIQH5SECTIONTf-lRLJDIVERSIUNTUNNE.LEL.14IQO'TOPa'>a:lCKFII..I..D'KE.---<_~~U~~~~ND\EME.R<iJ!.>,jC'r:>PILLWA"(p-E5UTME.NT~iDATE.---.-----------1--_-¥-_.~------~-------,---+-+-I--I~~_~~I-~-,-.-D-E-C--1-9-8-1--+.c.=~":":":=------r=:::-IQt.AlP.APP.ACRlSAMERICANIHCORPORATfDCONCRETE.l..INING~'TI-lk..1400-T>JRU5TP.>LOCI<.5CALE.O.~~~'~OO~iiiiiiiiiiii~2COFeeTi:!SECTIONA-A:fzoii1!>50~wI-1500-~1450STOPLOGGUICE'S'_a__·'500-900-1'200-800-1100-I!>OO-,000-,400900-aoo-,!!lCXl-,400-1100-,000-1'200~1500-I-::llJ.;!:Zo~,.uJ-luJ900-1100-1000/'\\\'.\\''\\MO."TWI..,IcL.9.'2.S,'L--.J~~CDNC.~TE.WNIN(iDOWW5T~H1OFAU)ll.IL."A.~DAMSECTIONATiNE.lRPROFILE..OFEMEQGECYSPILLWAY-II,'!--REL-'E.~~"-40'''',I/,!~(-GROUTculCTA.IN..ACO...,CSZe.TELININGA.,5E.ci10NA,SPILLWAYAQCH-GRAVI,YDAMLAVOU,900-soo-1100-~'000-;!:zo~WJW1500-I-UI,400-W~h?zI~OO-Cl~~''ZOO-W-luJ1100- Z300PLATEH3WATANAARCHDAMGEOMETRYI22.15~S.651502.210033.0S454S1950S2..5454'-(pISOOZ9.037374180031.041.544.:s11#5029.040.541TABLEOFARCHANGLESGEOMETRYTYPICALARCHSECTIONCENTRA.L.$EGMENT/l/A.omDE.C.19811----+"'""-------~--------+-+-I--Ii.'V1_'LrJ~I-o-~-..-~-=.~-'---''----f=;;;;;;-;;;:---r.=lI-:D::::AT=E--l';='1------~-'-;;;:REV;:;IS:::,DHS=------L--+:at::-.+-APP-.f-:.APP--:-F,.A~AMERi"cANi;CoRpQRATEo+.-.-o,-""------f'....·uvNOTES:I.)'PCC'INDICATESpOI~TOFCHAN6EOOFCURVATURE.2.}'c:'INDICA-TE.SCEN~OFE><.TAAPOSARCH.•3.1'I'INDICA.TEOSCEONT~OFINTRADOSA.RCI-\.4.)THE:SUBSCRIPT'0'INDICo'Te:SOUT!P\SEGMENT.e.)THESUBSC.RIPT'c'INDICATEOsCENTRAl.SEGMEONT.(".)THESUeScR.IPT'I.:'INDICA.TESI.E.PTSIO.OFARcHl.OOKINGUI'STREOAM.7.)THEOSUB.SCRIPT'R'INDICA.T!SRIGHTSlOEofARCHl.OOKINGUPSTReAM.6.1THRUSTBl.OCK5AREONOTSHOWN.9.}CONTOURI.INEOSsHOWGROUNDSURPACi::GENERALARRANGEMENT,THRUST,el.OCKl'f.C.S_---?PCC4:------A~~~?I'Cc.~pU::z.pCC12100--22002000-1900IhOO ------THRUST&1.0CI<..emDEC.1981WATANAARCHDAMGEOMETRYPLATEH4IliumII--~-uL-s~-T5_NK_A_A_H-~_~-R-~-E-~-~-cA_TR-~-:_H_p_~-OR~JI_~_~--ISOUNDROCKSURFACE.GROUNDSURFACEDOWNSTRE.AMFACEOFABUTMENT"l200(NOTDEVELOPED)"l000EL.2215'EL./3",0'LC2.•3300'lACRO~~VAI.I.E.Y)340032003000EXTRADOSFACECENTERLINE2200240021D002.600DISTANCE(FT.)INTRADOSFACECENTERLINE16002000IIDOOR,»<.IS0 •4050'.,.I---I'-c-''I------~-==:=_----~-_+:_If_+__+-'',....~.:~~~::~+_-----___J:>DATEREVISIONlACRESAM::R1CANINCORPORATEDPROJECTPROFILEOFDAMLOOKINGUPSTREAM1400E)(CAVATIONLINE.(DOWNSTREAMFAce01"ABUTMENT)---~--#----LINEOFINTRADOSCENTERSLINEOFEXTRADOSCENTERSFORCENT~LSEGMENTS01"INTI"i'OOS"::'>-<::::-=--'-iFa~II.-\NE.E\...2215'=1350SECTIONSALONGPLANESOFCENTERS-....IIIIl)'"..."'i00'"iii-\0III.J'...-s'"0....~1086.5848'2HiI-''"~6>002UI1055.9139'uZ~800108(o."'i011'ltln10001367.500U:1734-7se~DICE120025002300----2100~~1900°2CE-"988.189107'(NOTTOSCALe)z02200~:>1700III--lW2100150013001400uJJ«~zwoo01200l-lLt-""0III<Il62400~~,1000<Ii-1\I...'"0...'"Oliii22000")000....NI-'~Z2000~~OO0~uJ>'"w2"'iE"IIJ1800~"100w20'0175'SESIIIDOO200iDEE\...1360'140007E1200 APPENDIXI -ENVIRONMENTALSTUDIES"Whileperforminganenvironmentalreviewofthevariousdevelopmentoptions,'withintheSusitnaBasin,Acres'environmentalsubconsultant,TES,preparedtworeportsentitled"PreliminaryEnvironmentalAssessmentofTunnelAlternatives",and"EnvironmentalConsiderationsofAlternativeHydroe1ectricDevelopmentSchemesfortheUpperSusitnaBasin".Thesereportsassubmitted,arecontainedinthisAppendix.1.1-SummaryThesereports,augmentedbyadditionalinformationthatbecameavailablesubsequenttotheirpreparation,formedthebasisofthecomparisonoftheDevilCanyonDamwiththetunnelalternativeandthereachbyreachcomparisonofWatana/DevilCanyonversusHighDevilCanyon/Veedevelopmentplans.,TheenvironmentalassessmentsofthermaldevelopmentsandofalternativehydroelectricdevelopmentsoutsideoftheSusitnaBasinaregiveninAppendixBandC,respectively.(alDevilCanyonDamversusTunnelAlternative(ilEnvironmentalComparisonTheenvironmentalcomparisonofthetwoschemesissummarizedinTableB.1.Overall,thetunnelschemeis'judgedtobesuperiorbecause:'-Itoffersthepotentialforenhancinganadromousfishpopulationsdownstreamofthere-regulationdamduetothemoreuniform'flowdistributionthatwillbeachievedinthisreach.-Itinundates13mileslessofresidentfisherieshabitatinriverandmajortributaries.-Ithasalowerimpactonwildl,ifehabitatduetothesma11erinundationofhabitatbythere-regulationdam.-Ithasalowerpotentialforinundatingarcheologicalsitesduetothesmallerreservoirinvolved.-ItwouldpreservemanyoTthecharacteristicsoftheDevilCanyongorge,whichisconsideredtobeanaestheticandrecreationalresource.(ii)Socia1ComparisonTable1.2summarizestheevaluationintermsofthesocialcriteriaofthetwoschemes.Intermsofimpactonstateandlocaleconomicsandrisksduetoseismicexposure,thetwoschemesareratedequally.However,thedamschemehas,duetoitshigherenergyyield,morepotentialfordisplacingnonrenewableenergyresourcesandthereforescoresaslightoverallplusintermsofthesocialevaluationcriteria.I-I Amajorfactortobeconsideredincomparingthetwodevelopmentplansisthepotentialeffectsoncaribouintheregion.Itisjudgedthattheincreasedlengthofriverflooded,especiallyupstreamfromtheVeedamsite,wouldresultintheHighDevilCanyon-VeeplancreatingagreaterpotentialdiversionoftheNelchinaherd'srange.Inaddition,alargerareaofcaribourangewouldbedirectlyinundatedby'theVeereservoir.TheareafloodedbytheVeereservo'irisalsoconsideredimportanttosomekeyfurbearers,particularlyredfox.InacomparisonofthisareawiththeWatanaCreekareathatwouldbeinundatedwiththeWatana-DevilCanyonscheme,theareaupstreamofVeeisjudgedtobemoreimportantforfurbearers.1-2 Aspreviouslymentioned,betweenDevilCanyonandtheOshetnaRivertheSusitnaRiverisconfinedtoarelativelysteeprivervalley.Alongthesevalleyslopesarehabitatsimportanttobirdsandblackbears.SincetheWatanareservoirwouldfloodtheriversectionbetweentheWatanaDarnsiteandtheOshetnaRivertoahigherelevationthanwouldtheHighDevilCanyonreservoir(2200feetascomparedto1750feet),theHighDevilCanyon-Veeplanwouldretaintheintegrityofmoreofthisrivervalleyslopehabitat.Fromthearcheologicalstudiesdonetodate,theretendstobeanincreaseinsiteintensityasoneprogressestowardsthenortheastsectionoftheUpperSusitnaBasin.TheHighDevilCanyon-Veeplanwouldresultinmoreextensiveinundationandincreasedaccesstothenortheasterlysectionofthebasin.Thisplanisthereforejudgedtohaveagreaterpotentialfordirectlyorindirectlyaffectingarcheologicalsites.DuetothewildernessnatureoftheUpperSusitnaBasin,thecreationofincreasedaccessassociatedwithprojectdevelopmentcouldhaveasignificantinfluenceonfutureusesandmanagementofthearea.TheHighDevilCanyon-VeeplanwouldinvolvetheconstructionofadamattheVeesiteandthecreationofareservoirinthemorenortheasterlysectionofthebasin.ThisplanwouldthuscreateinherentaccesstomorewildernessthanwouldtheWatana-Devi1Canyonscheme.Sinceitiseasiertoextendaccessthantolimitit,inherentaccessrequirementsareconsidereddetrimental;theWatana-Devi1Canyonschemeisjudgedtobemoreacceptableinthisregard.Exceptfortheincreasedlossofrivervalley,bird,andblackbearhabitat,theWatana-Devi1CanyondevelopmentplanisjudgedtobemoreenvironmentallyacceptablethantheHighDevilCanyon-Vee·p1an.AlthoughtheWatana-Devi1CanyonplanisconsideredtobethemoreenvironmentallycompatibleUpperSusitnadevelopmentplan,theactualdegreeofacceptabilityisaquestionbeingaddressedaspartofongoingstudies.(ii)SocialComparisonTableB.2summarizestheevaluationintermsofthesocialcriteria.Asinthecaseofthedamversustunnelcomparison,theWatana-DevilCanyonplanisjudgedtoh~veaslightadvantageovertheHighDevilCanyon-Veeplan.Thisisbecauseofitsgreaterpotentialfordisplacingnonrenewableresources.1.2-TESReportReportspreparedbyTESontheenvironmentalassessmentoftheDevilCanyonDarnversustheTunnelalternativeandWatana/DevilCanyonversusHighDevilCanyon/Veedevelopmentplansaregivenintheirentiretybelow.1-3 ALASKAPOWERAUTHORITYSUSITNAHYDROELECTRICPROJECT.oPRELIMINARYENVIRONMENTALASSESSMENTOFTUNNELALTERNATIVESbyTerrestrialEnvironmentalSpecialists,Inc.Phoenix,NewYorkforAcresAmericanIncorporatedBuffalo,NewYorkDecember15,19BO TABLEOFCONTENTSPage1 -INTRODUCTION..............................................12 -COMPARISONOFTUNNELALTERNATIVES................•.•.......32.1.Scheme1........................................32.2Scheme2........................................32.3Scheme3........................................32.4Scheme4..........52.5LocationofDevilsCanyonPowerhouse............52.6DisposalofTunnelMuck.........................63 -COMPARISONOFSCHEME3WITHCORPSOFENGINEERS'SCHEME....8APPENDIXA-DESCRIPTIONSOFTUNNELSCHEMESAPPENDIXB-AMENDEDDESCRIPTIONOFTUNNELSCHEME4J1./ 1 -INTROOUCTIONInresponsetoarequestbyAcresAmerican,Inc.forinputintoSubtask6.02ofth.eSusitnaHydroelectricProjectfeasibilitystudy,TerrestrialEnvironmentalSpecialists,Inc.(TES)didapreliminaryassessmentoftunnelalternatives.,Theobjectivesofthisassessmentwere:(1)tocompareenvironmentalaspectsoffouralternativetunnelschemes;(2)tocomparethebesttunnelscheme,asselectedbyAcres,withthetwo-damscheme(WatanaandDevilsCanyon)proposedby.theU.S.ArmyCorpsofEngineers;(3)tocomparetworevisedlocationsforthedownstreampowerhouse;and(4)tocommentonalternativemethodsofdisposaloftunnelmuck,therockremovedtocreateatunnel.TheenvironmentalassessmentwasbasedonboththeprojectdescriptionsinaletterdatedOctober29,1980,fromAcrestoTES,asamendedbyaletterdatedDecember11,1980,andonconversationsbetweenrepresentativesofthesefirms.Copiesoftheselettersmaybefoundintheappendicestothisreport.Atthetimethisassessmentwasperformedcompleteinformationwasnotavailableonthevarioustunnelschemesunderconsideration.Therefore,TESviewsthisassessmentasonlyapreliminarystudy.OneassumptionmadebyTES,andconfirmedbyAcres,isthatthedam,poolelevation,andpoollevelfluctuationsofWatanaareasdescribedbytheCorpsofEngineersandwouldnotdifferamongthefiveschemes.If,onthecontrary,anyofthetunnelschemesincreasetheprobabilitythatthepoollevelatWatanamaybelowerthanthatproposedbytheCorpsorifaparticularschememaymoderatethepoolfluctuations,thentheenvironmentalassessmentofthetunnelschemesmay,inturn,beaffected.1.I ItisrecognizedthatanenvironmentalassessmentforrankingalternativeschemeSmustincludesomesubjectivevaluejudgements.Agivenschememaybepreferablefromthestandpointofoneenvironmentaldiscipline(e.g.fisheries)whereasanotherschememaybebetterfromanotheraspect(e.g.terrestrial·ecologyoraesthetics).To-recommendanyoneschemeoveranotherinvolvesthedifficulttaskofmakingtrade-offsamongtheenvironmental'disciplines.Suchtrade-offsarelikelytobecontroversial.2 2 -COMPARISONOFTUNNELALTERNATIVES2.1Scheme1Theenvironmentalimpactsassociatedwiththistunnelschemearelikelytobegreaterthanthoseofatleastoneofthe.othertunnelschemesevaluated(i.e.Scheme3).Themaincriterionforthisassessmentistheadverseeffects,particularlyonfisheriesandrecreation,ofthevariabledownstreamflows(4000-14000cfsdaily)createdbytheDevilsCanyonpowerhousepeakingoperation.·Othernegativeimpactswouldresultfromconstructionofboththere-regulationdamandarelativelylongtunnel.TunnelimpactsaresimilartothoseofSchemes2and4andincludedisturbanceofSusitnatributariesasaresultoftunnelaccessandthepotentialproblemsassociatedwithdisposalofarelativelylargevolumeoftunnelmuck.2.2Scheme2LikeSchemeI,thisschemeinvolvesadverseenvironmentalimpactsassociatedwithvariabledownstreamflowscausedbypeakingoperationattheDevilsCanyonpowerhouse(4000-14000cfs).Withoutthere-regulationdam,however,lesslandwouldbeinundatedandtheimpactsassociatedwithconstructionofthisrelativelysmalldamwouldbeavoided,althoughflowfluctuationsaboveDevilsCanyonwouldbemoresevere.LikeScheme1too,thelongtunnelproposedherewillhavenegativeconsequences,includingdisturbanceoftributariesfortunnelaccessandthepotentialproblemsconnectedwithtunnelmuckdisposal.2.3Scheme3Theoverallenvironmentalimpactofthisschemeisconsideredlessthanthatrelatedtothetwopreviousschemes,andalsolessthanthatrelatedtothefourthschemeasamended(AppendixB).Therelativelyconstantdischarge(aboutB300-8900cfs)fromtheDevilsCanyonpowerhouseisdesirableformaintainingdownstreamfishhabitatandrecreationalpotential.Sinceitmayallowanadromousfishaccessto3.I apreviouslyinaccessibleIS-milestretchoftheSusitnaRiver,Scheme3could,infact,offerarareopportunityforenhancementofthefisheriesresource.Thenewlyavailablesectionofrivercouldperhapsbeactivelymanagedtocreateorimprovespawninghabitatforsalmon.Thismitigationpotentialisdependentuponthelocationofthedownstreampowerhouse(aboveorbelowthepresentrapids)andthedeterminationofwhetherprojectflowsthroughDevilsCanyonwillstillconstituteabarriertofishpassage.Thedataneededforthisdeterminationarenotyetavailable.Acompensationflowreleaseof1000cfsatthere-regulationdamisnotthesameas1000cfsattheWatanadam.Becausefewertributarieswillaugmentthecompensationflowunderthisre-regulationscheme,thecompensationflowwillneedtobeslightlygreaterthanwiththeotherschemestoresultintheequivalentflowatDevilsCanyon.Compensationflowshouldbesufficienttomaintainacertaindegreeofriverinecharacter,andthusshouldbekepttoamaximumevenintheabsenceofasalmonfishery.Ofcourse,iftheviabilityofatunnelschemeisjeopardized,theimpactsofthealternativeschememustbecomparedtotheimpactsofalessercompensationflow.Aswithanyofthetunnelschemes,thewildlifehabitatinthestretchofriverbypassedbythetunnelmightimprovetemporarilybecauseofanincreaseinriparianzonevegetation.WithScheme3,however,thisstretchofriverisshorterthanwiththeothertunnelschemes;soasmallerareawouldbenefit.Thewildlifehabitatdownstream·ofDevilsCanyonpowerhousemaywellbenefitfromtheflowfromthehydroelectricproject,regardlessofthetunnelschemechosen.Theimprovementstothathabitatmaybesomewhatgreater,though,withtheconstantflowsallowedinScheme3thanwiththevariableflowsresultingfrompeakingintheothertunnelschemes.Oneenvironmentaldisadvantageofthisschemecomparedtotheothersisthelargerareatobeinundatedbythere-regulationreservoir.Thisareaincludesknownarcheologicalsitesinadditiontowildlifehabitat.Nevertheless,itisfeltthatthisdi~advantageisoffsetbythemorepositiveenvironmentalfactorsassociatedwithconstantdischargefromtheDevilsCanyonpowerhouse.4['IIIII·.'I,.IIIII,1.,1apreviouslyinaccessibleIS-milestretchoftheSusitnaRiver,Scheme3could,infact,offerarareopportunityforenhancementofthefisheriesresource.Thenewlyavailablesectionofrivercouldperhapsbeactivelymanagedtocreateorimprovespawninghabitatforsalmon.Thismitigationpotentialisdependentuponthelocationofthedownstreampowerhouse(aboveorbelowthepresentrapids)andthedeterminationofwhetherprojectflowsthroughDevilsCanyonwillstillconstituteabarriertofishpassage.Thedataneededforthisdeterminationarenotyetavailable.Acompensationflowreleaseof1000cfsatthere-regulationdamisnotthesameas1000cfsattheWatanadam.Becausefewertributarieswillaugmentthecompensationflowunderthisre-regulationscheme,thecompensationflowwillneedtobeslightlygreaterthanwiththeotherschemestoresultintheequivalentflowatDevilsCanyon.Compensationflowshouldbesufficienttomaintainacertaindegreeofriverinecharacter,andthusshouldbekepttoamaximumevenintheabsenceofasalmonfishery.Ofcourse,iftheviabilityofatunnelschemeisjeopardized,theimpactsofthealternativeschememustbecomparedtotheimpactsofalessercompensationflow.Aswithanyofthetunnelschemes,thewildlifehabitatinthestretchofriverbypassedbythetunnelmightimprovetemporarilybecauseofanincreaseinriparianzonevegetation.WithScheme3,however,thisstretchofriverisshorterthanwiththeothertunnelschemes;soasmallerareawouldbenefit.Thewildlifehabitatdownstream·ofDevilsCanyonpowerhousemaywellbenefitfromtheflowfromthehydroelectricproject,regardlessofthetunnelschemechosen.Theimprovementstothathabitatmaybesomewhatgreater,though,withtheconstantflowsallowedinScheme3thanwiththevariableflowsresultingfrompeakingintheothertunnelschemes.Oneenvironmentaldisadvantageofthisschemecomparedtotheothersisthelargerareatobeinundatedbythere-regulationreservoir.Thisareaincludesknownarcheologicalsitesinadditiontowildlifehabitat.Nevertheless,itisfeltthatthisdi~advantageisoffsetbythemorepositiveenvironmentalfactorsassociatedwithconstantdischargefromtheDevilsCanyonpowerhouse.4 2.4Scheme4Scheme4,asoriginallydescribed(AppendixA),wasdeterminedtobeenvironmentally·superiortotheothertunnelschemes,becauseofconstantdownstreamflowscombinedwiththelackofalowerreservoir.However,Acres'analysisdeterminedthatthisbaseloadoperationismostlikelyincapableofsupplyingthepeakenergydemand..Scheme4,asamended(AppendixB),isapeakingoperationatWatanawithbaseloadoperationatthetunnel.SincethenetdailyfluctuationsinflowbelowDevilsCanyonwouldbeconsiderable(intheorderof4000-13000cfs),theamendedScheme4wasjudgedaslessdesirablethanScheme3fromanenvironmentalstandpoint.AlthoughScheme4wouldavoidtheimpactsassociatedwiththelowerdamanditsimpoundment·(asplannedunderScheme3),theadverseimpactsthatwouldresultfromfluctuatingdownstreamflowsareconsideredtobeanoverridingfactor.Another,lesssignificantdisadvantageofScheme4(andsharedbySchemes1and2)incontrasttoScheme3isthelongertunnellengthplannedfortheformerand,perhaps,theproposedlocationofthetunnelonthenorthsideoftheriver.Thesiteschosenfordisposaloftunnelmuckandfortherequiredaccessroadsinanyoftheseschemes(asyetundetermined)willfurtherinfluencethiscomparison.2.5LocationofDevilsCanyonPowerhouseAlternativelocationsfortheDevilsCanyonpowerhousehavebeenproposed.Theseconsistofanupstreamlocationabqut5milesabovetheproposedCorpsofEngineersdamsiteandadownstreamlocationabout1.5milesbelowPortageCreek,asalternativestothesiteillustratedinAppendixA.ThemajorenvironmentalconsiderationisthatapowerhouseupstreamofDevilsCanyonwouldpreservemuchoftheaestheticvalueofthecanyon.Inaddition,theshortertunnelwouldconfineconstructionactivitiestoasmallerareaandmayresultinslightlylessgrounddisturbance,particularlyiftherearefeweraccesspoints,aswellasasmallermuckdispos~lproblem.Adownstreampowerhouselocation,ontheotherhand,mightcreatea5~! mitigationopportunitybyopeningupalongerstretchofriverthatperhapscouldbemanagedtocreatesalmonspawninghabitat.Untillarge-scaleaerialphotographsandcross-sectionaldataonthecanyonhavebeenreceivedandanalyzed,adeterminationcannotbemadeastowhetherprojectflowsthroughthecanyonwillstillconstituteabarriertofishpassage.Ourprimaryresponsibilityistoavoid,oratleasttominimize,adverseimpactstotheenvironment,anditmusttakeprecedenceoverourdesiretoenhanceorexpandaresource.Itisouropinionthatlosingaresource(theaestheticvalueoftheDevilsCanyonrapids)isworsethanlosingapossiblemitigationopportunity.Itisnotyetknownifthisopportunityevenexists.Furthermore,therearealwaysothermeansbywhichtoenhancethefishery,althoughnotnecessarilysoconvenientlyassociatedwiththehydroelectricproject.Thus,atthistimetheupstreampowerhouselocationispreferred.2.6DisposalofTunnel.MuckThereareanumberofoptionstobeconsideredfordisposaloftherockremovedincreatingthetunnel.Theseinclude:stockpilingthematerialforuseinaccessroadrepair,constructionofthere-regulationdam,orstabilizationofthereservoirshoreline;disposalinWatanareservoir;dikeconstruction;pile,cover,andseed;anddisposalinaravineorotherconvenientlocation.Itisunlikelythatthemostenvironmentallyacceptableoptionwillalsobethemosteconomical.Becausemanyunknownfactorsnowexist,afirmrecommendationcannotbemadewithoutfurtherevaluation.Itisquitelikely,however,thatacombinationofdisposalmethodswillbethebestsolution.Stockpilingatleastsomeofthematerialforaccessroadrepairsisenvironmentallyacceptable,providedasuitablelocationisselectedforthestockpile.Perhapsthematerialcouldbeutilizedforconstructionofanyoftheaccessroadspursortemporaryroadsthatarenotalreadycompletedatthetimethetunnelisdug.6 Anotheracceptablesolutionmightbetostockpilethematerialforuseinconstructionofthere-regulationdam.Thisrockcouldalsobea..potentialsourceofmaterialforstabilizationofthereservoirshorelineifrequired.Aswiththepreviousoption,anenvironmentallyacceptablelocationofthestockpilewouldberequired.DisposalofthematerialinWatanaReservoirmightalsobeenvironmentallyacceptable.Considerationshouldbegiventothefeasibilityofusingthematerialintheconstructionofanyimpoundmentcontrolstructuressuchasdikes.Asmallamountoftunnelmuckcouldpossiblyalsobeusedforstream.habitatdevelopment.Withanyoftheseoptions,thepossibletoxicityofmineralsexposedto.thewatershouldbefirstdeterminedbyassay,ifthereisanyreasontosuspecttheoccurrenceofsuchminerals.Topile,cover,andseedthematerialisworthyoffurtherconsideration,andwouldrequireproperplanning.Forexample,borrowareasusedindamconstructioncouldperhapsberestoredtooriginalcontourbythismethod..Thesourceofsoilforcoverisamajorconsideration,asearthshouldonlybetakenfromanareaslatedforfuturedisturbanceorinundation.Iftruckingsoilfromthereservoirareaisdeterminedtobefeasible,itmightalsobeworthwhiletotransportaportionofthemuckbackfordisposalinthereservoirarea.Themosteconomicalsolutionmightbetofillaravinewiththematerialortodisposeofitinanotherconvenientlocation.Unlessthechosendisposalsitewilleventuallybeinundated,however,suchanarrangementisenvironmentallyunacceptable,especiallysincebetteroptionsareobviouslyavailable.7 I3 -COMPARISONOFTUNNELSCHEME3WITHCORPSOFENGINEERS'SCHEMEScheme3emergedassuperiorinAcres'preliminaryeconomicandtechnicalscreening.AfteramendmentofScheme4,Scheme3wasalsoconsideredtobethebestschemefromanenvironmentalstandpoint.Therefore,Scheme3istobecomparedwiththetwo-damschemeproposedbytheU.S.ArmyCorpsofEngineers.FurtheranalysiswillbeinorderaftercompletedetailsareavailableonTunnelScheme3.Atpresent,manygapsexistintheavailabledata.Additionalinformationondesign,operation,andhydrology,combinedwithenvironmentalfieldinvestigationsatthelocationsofprojectfacilities,wouldpermitamuchmoredetailedcomparisonofthesetwodevelopmentalternatives.Nevertheless,fromwhatispresentlyunderstoodaboutScheme3,thereislittledoubtthatitis,byfar,environmentallysuperiortotheCorpsofEngineers'proposal.Ofcourse,extensiveadditionalstudyneedstobeperformedonwhateverschemeisselectedtoidentifyitsimpactsandtodevelopmitigationplans.TunnelScheme3has,byanymeasure,alessadverseenvironmentalimpactthantheCorpsofEngineers'scheme.Byvirtueofsizealone,construc-tionofthesmallerdam(245ft.)wouldhavelessenvironmentalimpactthantheDevilsCanyondamproposedbytheCorps.TherivermilesfloodedandthereservoirareacreatedbytheScheme3re-regu1ationdamwouldbeabouthalfthoseoftheCorps'planforDevilsCanyon,therebyreducingnegativeconsequences,suchaslossofwildlifehabitatandpossiblearcheologicalsites.Inaddition,theadverseeffectsupontheaestheticvalueofDevilsCanyonwouldbesUbstantiallylessenedwithScheme3,particularlywiththepowerhouselocationupstreamoftheproposedCorpsdamsite.Furthermore,TunnelScheme3maypos~ib1ypresentararemitigationopportunity,bycreatingnewsalmonspawninghabitatthatcouldbeactivelymanaged.WiththeincreaseinriparianzonevegetationallowedbyScheme3,thewildlifehabitatinthestretchofriverbypassedbythetunnelmightbetemporarilyimproved.TheimpactsassociatedwithtunnelaccessanddisposaloftunnelmucknecessitatedbyScheme3aremorethanoffsetbytheplan'sadvantages.Thus,TunnelScheme3farexceeds,theU.S.ArmyCorpsofEngineers'proposalintermsofenvironmentalacceptability.8 APPENDIXADESCRIPTIONSOFTUNNELSCHEMES OtherOllices:Columbia.MD:Pittsburgh.PA:Raleigh.NC:Washington.DCOctober29,1980P5700.06T507Telex91-6423ACRESaUFTelephone716-853-7525ConsultingEngineersTheLibertyBankBuilding.MainatCourtBullalo.NewYork14202Scheme1iscomposedoftheCOEWatanaDamandpowerhouse,andasmallre-regulationdamwithpowertunnelsleadingtoapowerhouseatDevilCanyon.PeakingoperationswilloccuratbothWatanaandtheDevilCanyonpower-houses.AconstantcompensationflowdischargewillbeprovidedbetweenWatanaandDevilCanyon.PeakingoperationswillcreatedailywaterlevelfluctuationsofunknownmagnitudedownstreamofDevilCanyon.ACRESAMERICANINCORPORATEDh',,:n',DearVince:SusitnaHydroelectricProjectSubtask6.02Attention:VinceLucidTerrestrialEnvironmentalSpecialists,Inc.R.D.1Phoenix,NY13135Scheme2iscomposedoftheCOEWatanaDamandpowerhousewithpowertunnelsfromtheWatanaReservoirtoapowerhouseatDevilCanyon.UponcompletionofthetunnelschemetheWatanapowerhousewillbereducedto35MWandwillsupplyaconstantcompensationflowbetweenWatanaandDevilCanyon.TheDevilCanyonpowerhousewilloperateasapeakinghydrofacility.WaterlevelfluctuationsdownstreamofDevilCanyonaresimilartothatofScheme1.Wewouldlikeyoutoreviewtheenvironmentalaspectsofthetunnelalter-native(Subtask6.02),whichyouwereintroducedtoonOctober3,1980.YourenvironmentalassessmentwillbeincludedintheSubtask6.02close-outreport,November1980.Inordertocompletethisclose-outreportonscheduletheenvironmentalassessmentisrequiredbyNovember13,1980.Theenvironmentalassessmentshouldincludeasmallsectiononeachofthefourtunnelschemes(SchemesI,2,3,&4).Physicalfactorsoftheschemes-andtheCOEselectedplan.arepresentedinTable1.Tunnelschemeplanviewandali9nmentsareenclosed.Scheme3iscomposedoftheCOEWatanaDamandpowerhouse,andare-regulationdamwithpowertunnelsleadingtoapowerhouseatDevilCanyon.TheWatanapowerhousewilloperateasapeakingfacilitywhichdischargesintoare-regulationreservoir.There-regulationreservoiriscapableofstoringthedailypeakdischargesandreleasingaconstantdischargeintothepowertunnels.Afourfootdailywaterlevelfluctuationinthere-regulationreservoirisrequired.TheDevilCanyonpowerhousewilloperateasabaseloadfacility,thus,nodailywaterlevelfluctuationswilloccurdownstreamofDevilCanyon. ACRESAMERICANINCORPORATEDRJW:ccvOctober29,1980- 2-Stockpileanduseforaccessroadrepairs._Stockpileandusefordammaterial(Scheme3only).-DumpinWatanaReservoir.-Fillthenearestravine.-Leaveinthemostconvenientlocation.-Pile,cover,andseed.;Z:-.J~,~01-.c?KevinYoungPleasedonothesitatetocontactmeforanyadditionalinformationthatmayberequired.TheobjectiveofSubtask6.02istocomparethebesttunnelschemewiththeCOEselectedscheme(HighWatanaandDevilCanyon).TheenvironmentalassessmentshouldincludeasectioncomparingtheimpactsoftunnelScheme3withtheCOEselectedscheme.Includeconclusionsandadescriptionofadditionalstudyrequired.Inregardstodisposaloftunnelmuck(rockremoved,tocreatetunnel)wecanassumethatadditionalcostswillbeincuredtodisposeofthemuckinanenvironmentallyacceptablemanner.Anenvironmentalassessmentofalternativedisposalmethodswouldhelptodefinethisaddedcost.Thefollowinglistsonlyafewdisposalideas,feelfreetoconsiderothers.ThegenerallayoutofScheme4issimilartoScheme2.Scheme4isabaseloadschemeandhasaverylimitedpotentialtoproduceadditionalpeakenergy.DailywaterlevelfluctuationsdownstreamofDevilCanyonaresimilartoScheme3.PreliminaryeconomicandtechnicalscreeningshowedScheme3assuperior.PreliminaryenvironmentalassessmentrankedScheme4environmentallysuperior.Scheme4ismostlikelynotcapableofsupplytherequiredpeakenergydemand.Thus,Scheme3,rankedsecondenvironmentally,wasprelim-inarilychosenasthebesttunnelscheme.IfyoushoulddisagreewiththeselectionofScheme3pleasecontactmeassoonaspossible.VinceLucidTerrestrialEnvironmentalSpecialists,Inc.III\1'!II!",II!I' TABLE1SusitnaTunnelSchemesPhysicalFactors..COEDevilCanyon12347.500320-0-3.900-0":31.62.0-0-.15.8-0-272915.8.29--10.749.00011.545,0004,285,0006.494,000500500500500"totototq10001000 10001000streamervoirVolume,re-Feet)1,100.0009.500-0-350.00'0-O-ilCanyonerhousechargeConstantPeakingPeakingConstantConstantHeightet)52075245I DEcFG302UNDE.RGROUNDPOWERl-lOLJSE3sUQGETANK.--4,LuJwc1U56FLOW-POWE.RTUNNE:LSCHEMES2q4.aINTAK.E.(5C~EME9ACCE.SSADITMAX.H.W.L,E.L.22C01I5CHE,ME.5'2~4II.!1025=3000F========~~E~I===========~=~~~~~-=======-=========_====_=====soo'-------:>__;__~~------,;--------;;;---------;c----~---=~=---L'510:4:;;11520"C'''''"'NM'coo"NORTHE.R.NALIGNM--(t.Ni5Cf-IE.ME5I,'2q,4)10002'0001500NOTES:A8,LI.)TUNNELALIGNMEN.TF"O~SCHEME.3IS5HOWNONDRAWINGN~5700.cG:,-;1-z.2)ALLPLANSANDPROFILESFORCONCEPTJALSTUDYpuRPOSESONLY.IUIRII-;;-A~lA~S:;-:-KA-::-::-P::-:O-.:-W:-E_R_A_U_TH_O_R....:.-IT~Y-lSUS1TNAHYDROELECTRICPROJECTPLATEUNDERGROUNDPOWE.RHOUSE.25SURGE.TANK.;201uJ1~cJvT.v\!.L.EL67C'iO::===~~=====~~~~15/POwE.;:<,UNNELI::>'2.000l-l.W.L.EL1SCO'lSCHEMEI)3SOO1500~=-----l-----3CCO1000IMAX.H.W.LE.LrL'200\I-'lS:)QJ:~e:,ME.:S'2.44~wuJuJLLuJrizI)z2=Q1-<l>uJ1500-lIII1000SOO05DiSTANCE.INM1L-E..51098D\QECT7ALIG NMENT(SCI-F'ME..SI,'Z.14')+DATE4Re....ISION'S3CONCEPTUALTUNNELSCHEMESPLANaSECTIONS oAGEcBF,e.O'OI"'.SURGE.TANI4S2II\IIIIIIIII1\IIIIII1\\IIIII".t~\\\\"IIII)I./\IIII1\~~'2-?>o'DIA,\~POWERTUNNEL'SIIIIII IIIIII34GENERALARRANGEMENTPEVILCANYONi=t::>W£Rl-IOU5ESCALE0400800FE.ETi!5ALLPL"-N5ANDLAYOUTSFORCONCEPTUALSTUDYpuRPOSESONL.Y.NORMALTW.L",12<00'6PLAN~----------__rUN-~~---!:!~4.1...RE-"<EGUL-ATIONDAM...i~---!.~~E:.N.,.o----~C!:!..i:."-11;.r---2....'i-I//DEVILCANyONPOWE.R1-40USEj/'/)"-'iOE",VC!.I=L~~'I,,~,,'-~/,~CANYON"'~A~rJ9J4i/~If~-40'101,SO'HIGHVERTICALL.IFTGATE.S'--~--------SPIL.LW"'YCRE'STEL./435,~NOTE.:SCl-1E.ME.':>72-';0'OIA_POWERTUNNEL5~=======-=~SCAL-EO~~~~iiiiiiiiiiiiii,:2MIL-£I.I25'DIAOIVE.RSIONfL-OWLEVELouTLETTUNNEl..8---------------GENERALARRANGEMENIRE,REGULATIONDAM9\NTAlo'..E.SCALE0300"00FEETiOATEREVISIONS109-+87t4653t.--------..._._~J'"10~/900SUS/TNA14001:';00----,,00\c,oo BAcDEFG,NORMA.l...T.W.LEL'lOO-COFF£RDAMI..TAILRACESTQ?LOGS"\\PREFERREDTUNNELSCHEME3SECTIONS22IMIRII--~-U-':-,-T:-~--H-~-D-A-~-E-~-~-C-:-AU-Ic_T_H_.O_A-~-J~-c-~-~PLATE3:-30'OIA.TA.IL'2b..C.E:.,TUNNE.1..10334I-o-.,-,---IC-.:'l-----------:."'"'v-:,,-:,""'------------+-""-.1-.,.-f-.,.-:-:-l.--~s_~I~TEo+------.....-!SCALE.'ATRANSFOR-ME.R..GAl.-LERYSCALE.A0100=FEE.T~i~~_iiiiiiiiiiil'5DISTANCE.INMIL-Eo5TUNN.E.LALIGNMENTtAL-1..STRUCTURALANDSLiPPORTDETAILSARECONCEPTU"LANDFORSTUDYPURPOSESONLY_NoTE;DEVILCANYONPOWERFACILITIESPROFILE5HEXNUTSTEEL?LIO"EoFA5TSETTINGGRouTGROUTASRE.QU/l2E.OC''"P)DE.TAILAOETAILe>W.W.F.6STEEL?LA'EFASTSETTI»6GROUT500L..__-"-__......1l-__-'---__--l'-__-'---__--ll-__-'---__......1L__---"--__---l_30002~ooI-WuJ2000Ii..~Z0~I~OO>uJ-'W1000ACCESSA.OITORIFICE-------SURGETANK----------(NOTTOSeAL.E)7ROCKBOLTS---I~OO15001400....ww"-!::1300:z~....I~OO«>w~w11001000000TYPICALTUNNELSECTIONS8,,SE.CTIONA-ASCALE.:A4OW.40HVE£T\CALL.IFT"c:"ATESROLLeDROCKFILLSPILLWAYPROFILESCAL-E.;A9CASTI»PL,ACE.cof'.lCRETELININ(')MAX.OPERATINGLEVel-INTAKE.GATESCALE.:Po..RE-REGULATIONDAMTYPICALSECTIONflA A~BEARIN6PI>DCONC.LINEDW/STEELSETPOWERTUNNELINTAKESECTIONRocl<BOLTSASREQUIREDNORMALMAX.EL.l475'UNLINEDTYPICALTUNNELSECTIONS(NOTToSCALE.)DETAILA.I<POOI~OO1500I~OO>-MIN.NORMALw...1500OPERATINGLEveL"-~EL.1470':z//fL141&'0;::1400<lTRASHRACK:>I~lw1300:zo~>~I!DO....ww"-='140010IGOO150014.00~~~I~OO:z0;::«>...I~OOoJw1100 APPENDIXBAMENDEDDESCRIPTIONOFTUNNELSCHEME4 December11,1980P5700.11.30T.606OffIcesColumbia.MD:PIttsburgh.PA.Raleigh.NC:Washington,DCCRESAMERICANINCORPORATEDInaddition,Ihavecompletedyourtableoutliningtunneldesigninformation.Sincerely,r-J..-/~:~~/~/_.~_~/'~~i_~~evinYoungEnvironmentalCoordinatorTelex91-6423ACRESBUFMr.VinceLucidTerrestrialEnvironmentalSpecialists,Inc.RD1Box388Phoenix,NewYork13135EnclosureKRY/ljrDearVince:SusitnaHydroelectricProjectRevisedDescriptionofTunnelAlternativesEnclosedpleasefindamemofromB.Wartoutliningourreviseddescriptionoftunnelalternatives.Pleaseusethisdescriptioninyourassessmentoftunnelalter-natives.onsultingEngineerseLibertyBankBuildmg.MainatCourtHaloNewYork14202 OFFICEMEMORANDUMSUBJECT:SusitnaHydroelectricProjectPreliminaryEnvironmentalAssessmentofTunnelAlternativesTheassumptionmadebyTESthatthedam,poolelevation,andpoollevelfluctuationsofWatanaareasdescribedbytheCorpsofEngineers,andwouldnotdifferamongthefiveschemesiscorrect.ThedescriptionoftunnelScheme4hasbeenrevisedsothatScheme4iscapableofsupplyingadailyloadcurvesimilartothatoftheotherschemes.ThereviseddescriptionoftunnelScheme4follows:Date:December11,1980File:P5700.07.07K.YoungB.WartFROM:TO:RJ~l/ljrThegenerallayoutofScheme4issimilartoScheme2.TheoperatiorofScheme4variesfromthatofScheme2andisdescribedbelow.TheWatanapowerhousewillremainatthestageoneinstalledcapaci~orifnecessaryenlargedslightly.PeakingdemandswillbemetwiththeWatanapowerhouse.AtalltimestheWatanapowerhousewillgenerateami~imumof35MWtosupplementbaseloaddemandsandsupplytherequiredcompensationflowbetweenWatanaandDevilCanyolTheDevilCanyonpowerhouseandtunnelwilloperateasabaseloadfacility.Scheme4failstodevelopthefullheadfortheentireflowandthusScheme4isnotexpectedtoproduceannualenergycomparabletootherschemes.DailywaterlevelfluctuationsdownstrtofDevilCanyonaresimilartoSchemes1and2.Waterlevelfluctua'betweenWatanaandDevilCanyonareexpectedtobelarge. susrTNA TUNNEL SCHEMES -PHYS[CAL FACTORS (Addendum) Typical COE 1 2 3 4 Range of discharge (cfs)daily 6 000 t.o 13,000 4,000 to 14,000 4,000 to 14 000 8 300 to 8 900 4 000 to 13 000 at Devil Canyon Powerhouse seasonal Fluctuations are less than existing natural fluctuations and are smaller for all plans. Range of river stage below daily SmaLl J Large I Large I Small I Large Devil Canyon powerhouse To date no detailed information is available. (corresponding to discharges A.d plans have ~dentical seasonal fluctuatlOns which are ~ess than natural fluctuations. 1 isted above)seasonal To date no information is available. Maximum fluctuations (ft)daily <1 Same as COE Same as COE Same as COE Same as COE in Watana Reservoir seasonal See Graph Same as COE Same as COE Same as COE Same as COE Maximum fluctuations (ft)dailY 2 Laroe NA 4 NA in downstream reservoir seasonal None None NA None NA Generating Capacity (MW)Watana 792 792 35 (792)*792 792 [)ev~l Canyon 776 550 1,150 365 365 Total Project Costs ($)2 150 000 000 2,502,100.000 2.394,600,000 2 144.300.000 2.074.200,000 Total Annual Enerqy (GwH)6 895 5,704 5,056 5 924 4,140 *Watana capacity is reduced after completion of tunnel project. JMTAHA litOHTHt.,Y STORAGE Fl*:QUENCY F<m Tl{£OEVIL CAW({»f I:..~WATAN·,.SYSTE~ [¥:fIT~~'I~r~.;·'~!;~~.~.~..;:,..n.;~.r~~:-:r-:'~f;J·~t.;~~:.;-·-~-~-~.:-r~ffrr1~-~;',::,-;,,~·n~?;·:I .. ., ~~--_",,_'-'--..:..- .~..:...~~::i ~;: ~~'.;':~;-~i, :'! ! ,..";I I ....~..~',: Appendix I GRAPH C-12 C-147 ... '"...... ~ :i oo ~ ~ ~ -';-;~!~·_;;~>~-;t-t;~~·":'ttrrn~t~t~~t",~;'0 ;.:,i:+i'~.>-;-~~.i 'IJOO:~..",:~.~.~~~.~... [i'·;';:;:. ,poo~:.~_~.:.~~:;,'.~!'i ...........~f :i _ ","00 .··r·,;.:!L_,_.,,,.. "II.~ "":""._~~_._,-~j~,~:}21f:~1-" 4,OO(lt-:':'"I,CVIVH l··~.,pC"~C..c,0''I"C ".UlOt "-:'.1M'Tot .~fA·,~PCUf,t CO"'[',"_III'C ....ACPORT ':.fi·:':.d~"PIC.:..,u,'·r lliOl~lT():;SOlJTHCEIiTRAI.RAIUIE!.T .:..,VOlU"!.AREA AI..ASKA~..DCvll 0','0..'0;,"£l:l '0 .....,t.. ,:,.-:.""'VIl H ....lTI'J..'A,V':~'I""Al",U CIIsrROCIs.ooo ..:,:Cit'.':.'1100 CO,VS 0'(':"'((11 '1«1:=.·r..:::L"_·=.·•.::,~.,..,.;:-..""Itt riPI :*.:.g~".:..':..:.-:--=...=i:~ CCT wt:N I)(C .we m MAll APII .Ii&AY ~u.y M SUT :Terrestrial,.nvironmentai'SpEcialists.inc.R.D.1BOX388PHOENIX,N.Y.13135January16,1981218.443ProjectManagerSusitnaHydroelectricProjectAcresAmerican,Inc.LibertyBankBuildingMainatCourtBuffalo,NewYork14202Attention:KevinYoungRe:AlternativeDevelopmentSchemesDearKevin:InresponsetoyourrequestofDecember10,1980,andasdiscussedinmylettertoyouonJanuary8,1981,TES,Inc.haspreparedsomecommentsontheVee/HighDevilCanyon/OlsonschemeincomparisonwiththeWatana/DevilCanyonscheme.Enclosedforyourreviewandco~mentisadraftofabriefreportentitled"EnvironmentalConsiderationsofAlternativeHydroelectricDevelopmentSchemesfortheUpperSusitnaBasin".Wewillbepleasedtodiscussthecontentsofthisreportwithyou.Sincerely,VincentJ.Lucid,Ph.D.EnvironmentalStudiesDirectorVJl/vlEne.cc:R.Krogseng Dw'.qC_::Z~.,-..'I;'.'!~..L..i~;1,J\".-JII;---:\iJI'jALASKAPOWERAUTHORITYSUSITNAHYDROELECTRICPROJECTENVIRONMENTALCONSIDERATIONSOFALTERNATIVEHYDROELECTRICDEVELOPMENTSCHEMESFORTHEUPPERSUSITNABASINbyTerrestrialEnvironmentalSpecialists,Inc.Phoenix,NewYorkforAcresAmerican,Inc.Buffalo,NewYorkJanuary16,1981 .".TABLEOFCONTENTS1 -INTRODUCTION2 -APPROACH2.1TheDevelopmentSchemes...."2.2AssumptionsofEnvironmentalConstraints3 -DISCUSSION. .3.1Socioeconomics.3.2CulturalResources.3.3LandUse3.4FishEcology3.5WildlifeEcology.3.6PlantEcology.3.7TransmissionLineImpacts....3.8AccessRoadImpacts3.9Summary. .4 -CONCLUSION....APPENDIXA-DESCRIPTIONOFSTAGINGALTERNATIVESPage1222333455789911 1 -INTRODUCTIONThisreportdocumentspreliminaryenvironmentalconsiderationsofalternativehydroelectricdevelopmentschemesfortheUpperSusitnaBasin.Theneedforthereportstemsfromdiscussionatameetingheld·inBuffaloonDecember2,1980betweenstaffofAcresAmericanandTES,Inc.ThealternativedevelopmentschemesaredescribedinaDecember4,1980memofromI.HutchisontoK.YoungfortransmittaltoTES,In~.(AppendixA).AdditionaldetailswereobtainedandtheapproachagreeduponinsubsequentconversationsanddatatransmittalbetweenK.YoungandV.Lucidconcerningthesealternativedevelopmentschemes.ThefollowingassessmentisbaseduponafamiliaritywiththeWatana/DevilCanyonareaobtaineddu~ingthefirstyearofenvironmentalstudies.Atthiswriting,however,wedonothavethebenefitofinformationtobecontainedinthe1980AnnualReports,whicharetobecompletedbyTESsubcontractorsbyMarch1981.BecausemuchoftheVeereservoirliesoutsideofthestudyareaformanydisciplines,commentsconcerningthisimpoundmentrelyheavilyuponintuitivejudgement. 2 -APPROACH2.1TheDevelopmentSchemesEnvironmentalconsiderationswerepreliminarilyidentifiedfortwodifferenthydroelectricdevelopmentschemesfortheUpperSusitnaBasin:Watana/DevilCanyonandVee/HighDevilCanyon/Olson.Thethreestagingvariationsforeachoftheseschemes(AppendixA)willlikelyhavedifferentshort-termimpacts,butanattempttoaddressthesepossibledifferencesatthistimewouldbetoospeculativeinmostdisciplinestobemeaningful.Indisciplinessuchassocioeconomicsandlanduse,however,thestagingofthedevelopmentwilllargelydeterminethemagnitudeofimpacts.Thus,theenvironmentalconsiderationsidentifiedinthisreportarebasedinmostcasesuponthetwoultimateschemeswithoccasionalreferencestothestagingoptions.Itwasassumedthatwhateverstagingalternativeisselected,allstagesofdevelopmentwouldbecompleted.TheresultwouldbeoneofthetwoschemesoutlinedinTable1.2.2AssumptionsofEnvironmentalConstraintsTheidentificationofpotentialadvantagesanddisadvantagesofthetwoschemes,fromanenvironmentalstandpoint,requiresthatcertainassumptionsbemadeconcerningenvironmentalconstraintsthatwillgovernthedesignandoperationofthefacilities.Amongtheseare:(a)thatconstant,ornearlyconstant,.downstreamflowsbemaintained,bothduringandafterdevelopment,whetherbymeansofare-regulationfacilityoroperationalconstraints;(b)thatdrawdownofthereservoirswouldbesimilarinmagnitudetocorrespondingreservoirsintheotherscheme(e.g.Watanavs.Vee),andwouldbewithinenvironmentalconstraints;and(c)thataminimumreleaseorcompensationflowbemaintained(ofavolumetobedetermined)topreservetheriverinehabitatbetweenthereservoirs.2 Table1DescriptionsofTwoAlternativeHydroelectric( )DevelopmentSchemesfortheUpperSusitnaBasinaMaximumpoolelevation(ft)DamHeight(ft)InstalledCapacity"(MW)ProbableOn-lineDateoflastStageDailyPeakingApproximate(b)ReservoirArea(acres)Approximate(b)RiverMilesFlooded(C)Watana/DevilCanyon2200/1450750/570800/6002010to2020Yes/No40,000/7,500(Total=47,500)60/30(Total=90)Vee/HighDevilCanyon/Olson2300/1750/1020425/725/120400/800/100+2020Yes/Yes/No16,000/21,700/900(Total-38,600)95/58/7(Total=160)aDerivedfromdescriptionsofthreestagingalternativesforeachscheme,whicharepresentedinAppendixA.bPreliminaryvalues.cMainstreamSusitnaonly,tributariesnotincluded. 3 -DISCUSSIONPotentialadvantagesanddisadvantagesofthetwodevelopmentschemesarepresentedbelowforeachofthemajorenvironmentalstudydisciplines.3.1SocioeconomicsTherecouldbesignificantdifferencesintype,degree,andchronologyofsocioeconomic'impactsresultingfromthevariousplansunderconsideration.Animportantconcernrelatestoalternativestagingplansandassociatedfactorssuchas:(a)costofstage,(b)schedulingofvariousstages(i.e.,lengthofconstructionperiodperstageandspacing),(c)constructionmanpowerrequirementsbytimeperiod,(d)accesspointoforigin,and(e)whetherornotaconstruction"community"willbeestablished.Impactsgenerallywillfallintotwo&ategories:thoseassociatedwithprojecteconomicsandconstruction,andthoseassociatedwithpowerproductionandsales.Bothtypesofimpactswillexhibitavarietyoflocal,Railbelt,andstatewideramifications.Intheabsenceofpracticallyanyprojecteconomicsinformation,detailedanalysisisimpossibleatthistime.Ingeneral,however,itcanbeexpectedthataschemeinvolvingon-lineproductioncapabilityof800MWbytheyear2000willhavegreaterandmoresignificantimpactsthanaschemeinwhichthatcapabilityisnotattaineduntil2010(e.g.,Plan1comparedtoPlan2).Thisdifferencewouldoccurbecause,inthelatterplan,thedemandonresourceswillbespreadoutovertime.Inaddition,itisreasonabletoexpectthattheeconomicbaseofMat-SuBoroughwillbelargerin2010thanin2000,evenwithouttheproject.Therefore,therelikelywouldbeagreatercapacitytodealwithprojectimpacts.3.2CulturalResourcesFieldsurveysintheWatana/DevilCanyonimpoundmentareaduringthesummerof1980havedocumented37archeologicalsites.Apreliminaryassessmentofthedataindicatesagreaternumberofarcheologicalsites3 towardstheeastendofthestudyarea.In1953,apreliminaryfieldsurveyconductedfortheNationalParkServicenearLakesLouise,Susitna,andTyoneidentifiedapproximatelysixarcheologicalsites.Thereisahighpotentialfordiscoveringmanymoresitesalongthelakes,streams,andriversinthiseasterlyregionoftheUpperSusitnaRiverBasin.AdditionalsitesareexpectedtobeidentifiednearcariboucrossingsoftheOshetnaRiver.Insummary,apreliminaryassessmentofavailableinformationsuggeststhatthereperhapscouldbeagreaternumberofarcheologicalsitesassociatedwiththeVee/HighDevilCanyon/OlsonschemethanwiththeWatana/DevilCanyonscheme.3.3LandUseAtpresent,muchoftheUpperSusitnaBasinissubjectedtoalmostnegligiblehumanactivity.Eitherofthedevelopmentschemes(andanyofthestagingplans)willcausechangesinlandusepatternsintheUpperSusitnaBasin.Regardlessoftheschemechosen,impactsonlocallandusageandhumanactivityintheUpperBasinwillbesignificantintermsofareainundatedandlandcoverchangesresultingfromprojectfacilities.WitheithertheWatana/DevilCanyonorVee/HighDevilCanyon/Olsonscheme,DeadmanFallswillbeinundatedandDevilCanyonwillbegreatlyreducedinscenicvalue.TheVee/HighDevilCanyon/OlsonschemewouldalsoeliminateTsusenaFallsandwoulddestroytheexistingaestheticsofVeeCanyonbydamconstructionatthissite.AlthoughtheVee/HighDevilCanyon/Olsonschemehasasmallerreservoirarea,itwouldinundateapproximately70milesmoreoftheSus~tnaRiverthanwouldtheWatana/DevilCanyonscheme(Table1).Developmentofarecreationplanfortheprojectwouldvaryaccordingtothedesignschemeandstagingplanselected.Broaderconcernsassociatedwithlandusearerelatedtostaging,asdiscussedintheprevioussectionregardingsocioeconomics.Theinfluenceofstagingonlanduseimpactsappliestolandusefactorsconcernedwithexistingregionaltransportationsystems.Theexistingtransportationsystems(andcommunitiesandlandusesassociatedwiththem)whichconnecttotheselectedaccessroutewillbeaffectedbyconstruction-relatedactivity.Inthiscontext,thedegreeof4 construction-relatedactivitywithinagiventimeframecouldbeasignificantfactor.Thisconsiderationissimilartothesocioeconomicconcernidentifiedpreviously.Theproportionatelygreaterdegreeofconstructionactivityassociatedwithaplaninwhich800MWcapabilitywouldbeachievedby2000-ascomparedwithoneinwhichthiswouldnotbeachieveduntil2010-concentratesimpactsonlandusesinashortertimeframe.3.4FishEcologyAlldevelopmentschemesmustbeexaminedwiththedownstreamanadromousfisheryreceivingprimaryconsideration.Anyschemeorstagingplanthatallowsfordailypeakingwithoutare-regulationdamdownstreamcouldbedetrimentaltothisresource.Therefore,themaintenanceofconstant,ornearlyconstant,downstreamflowsisanenvironmentalconstraintthatmustbemetforanydevelopmentschemetobeacceptable.TheVee/HighDevilCanyon/Olsonschemehasatleastonemajordisadvantage,withrespecttofishecology,incomparisontodevelopmentatWatana/DevilCanyon.ItisthattheOlsonsiteisdownstreamofPortageCreek,whichisknowntobeaveryimportantspawningstreamforsalmon.DamdevelopmentattheOlsonsitewouldprovideanobstructiontoanadromousfishpassageandtwomilesofPortageCreekwouldbeinundated.Evenwithfacilitiesforfishpassage,theimpactsonthisspawningareacouldbesevere.BecausetheVee/HighDevilCanyon/Olsonschemewouldinundateabout70additionalmilesoftheSusitnaRiver,plusdifferenttributaries,thanwouldtheWatana/DevilCanyonscheme,impactsonresidentfishcanbeexpectedtodifferbetweenthetwoschemes.Dataarenotpresentlyavailabletopermitan.assessmentoftheseimpacts.3.5WildlifeEcologyAlthoughtheareathatwouldbeinundatedbytheVeereservoirhasnotbeenthoroughlyinvestigated,projectpe~sonnelhavesufficientfamiliaritywiththeareatomakeafairlystrongrecommendationat~ thistime.Withtheexceptionofimpactsonavianspecies,itisfeltthattheWatana/DevilCanyonschemeissuperiorfromawildlifeimpactstandpointtotheVee/HighDevilCanyon/Olsonscheme.Thebasictrade-offsassociatedwiththiscomparisoninvolvetheareastobefloodedbytheVeedamasopposedtothefloodingofmuchoftheWatanaCreekdrainageandthehigherportionsofthecanyonwallsalongtheSusitna.ForavarietyofreasonstheareatobefloodedbytheVeedamseemsmorevaluableforwildlifethantheareasthatwouldbeinundatedbytheWatana/DevilCanyondams.AVee/HighDevi1Canyon/OlsonschemewouldfloodmoreacreageofcriticalriverbottomhabitatthanwouldtheWatana/DevilCanyonscheme.Theseareasareimportantformooseduringseverewintersandtheadditionalreductioninsuchhabitatcouldhaveamajorimpactonmoosepopulations.Inaddition,theVeeimpoundmentwouldfloodkeywinterhabitatforatleastthreesubpopulationsofmoosethatrangeoverlargeareaseastoftheSusitnaandnorthoftheMaClarenRiver.TheareathatwouldbesavedbytheVeedamscheme,theWatanaCreekdrainage,isinhabitatedbyasubpopulationofmoosethatappearstobedeclininginconditionandincreasinginage,thusindicatingthatwithin10to15yearsthissubpopulationmaybefarlessimportantthanatpresent.ThehabitatqualitywithintheWatanaCreekdrainagealsoseemstobedecreasing.TEShaspreviouslyrecommendedthatthepoolelevationofWatanabeloweredtopreserveasmuchoftheWatanaCreekdrainageaspossible.Nevertheless,thetrade-offbetweenWatanaCreekandtheVeeimpoundmentfavorsfloodingtheWatanaCreekarea.TheareathatwouldbefloodedbytheVeedamishistoricallyusedbytheNelchinacaribouherd,particularlyinmovingtotheircalvinggroundsnearKosinaCreek.Althoughcariboumovementpatternsarehighlyvariableandappeartochangeasthesizeoftheherdchanges,thisareahasbeenfrequentlytraversedbymembersofthisherd.ThepotentialforimpactingcariboumovementisgreaterthanwiththepresentWatanascheme.LikeWatana,theVeereservoirwouldbesubjecttolargedrawdownandpossibleice-shelving.Inaddition,thethree-damschemewouldresultinagreaterdivisionoftheNelchinaherd1srangeduetothegreaterlengthoftheimpoundmentsinvolvedandthusincreasethelikelihoodofimpactsonthisherd.6 ThereisanindicationthattheareatobefloodedbytheVeedamismoreimportanttosomekeyfurbearers,theredfoxinparticular,thanareassuchasWatanaCreekthatwouldbesparedbyaVeedam.ThereisalsomoretrappingconductedbyresidentsintheareaupstreamfromtheVeesitethaninareasdownstreamfromthatarea.TheVeedam,especiallyduetothedrawdownschedulethatwouldbeoperativewiththisdam,alsohasthepotentialofmoreseverelyimpactingbothmuskratandbeaverpopulations.ItappearsthatonlyavianspeciesmightsufferlessadverseimpactsfromtheVee/HighDevilCanyon/OlsonschemethanfromWatana/DevilCanyon.AlthoughtheVeedamwouldeliminatemoreriverbottomhabitat,itwouldspareaconsiderableamountofdeciduousforest(birchandaspen)thatexistsalongthesouth-facingslopesoftheSusitnacanyonandalongsomeofthetributaries.Thisistheonlyarea,ofanyextent,thatcontainsthistypeofhabitat,anditsassociatedavifauna,withintheUpperSusitnaBasin.Althoughamoredetailedrecommendationcouldbemadeifabetterdatabasewereavailable,thereasonsgivenaboveseemtoindicatethattheWatana/DevilCanyonschemeissuperiortoaVee/HighDevilCanyon/Olsonscheme.Thisisespeciallytrueifoneconsidersthatthegreatestpotentialformoresevereimpactsconcernmooseandcaribou,whichareunquestionablythekeybiggamespeciesinthearea.3.6PlantEcologyBothschemeswillprimarilyflooddeciduousforests(whitebirch,balsampoplar,andaspentypes),coniferouswoodlandsandforests(whitespruceandblackspruce),andshrubcommunities(alder,birch,andwillowtypes).Therelativeamountsofhabitatsfloodedwillvarywiththetwoschemes.TheVee/HighDevilCanyon/Olsoncombinationwillprobablyfloodmorefloodplainhabitatssuchasbalsampoplarforests,whiletheWatana/DevilCanyonschemewillprobablyfloodmorebirchandaspenforests.7 TheprimaryadvantageoftheVee/HighDevilCanyon/Olsonschemeisthatapproximately9,000feweracreswouldbeflooded(Table1).Theprimarydisadvantagesofthisschemeare:morelakesandwetlandsflooded,moreriverfloodplainsflooded,andagreateramountofassociatedfloodplainhabitats,suchasbalsampoplar,eliminated.Theamountofwetlandeliminatedwouldbeaverysmallproportionofthetotalwetlandintheregion.Nevertheless,theimportanceofwetlands,floodplains,andassociatedhabitatshasbeenemphasizedbyExecutiveOrdersandvariousfederalagencies.3.7TransmissionLineImpactsBecauseofthedistance'traversed,theconstructionofatransmissionlinetotheintertiefromaVee/HighDevilCanyon/OlsonprojectoffersseveraldisadvantageswhencomparedtoalineconstructedfromaWatana/DevilCanyonproject.AlinefromtheParksHighwaytoWatanawouldbeapproximately50milesinlength.FollowingthesameroutetoWatanaandextendingthelinetotheVeesitewouldaddapproximately40milestoitstotallength,anincreaseinmileageofsome80percent.Generally,thelongertheline,thegreatertheimpact.Inaddition,theaddedlengthwouldcrossapresentlyroadlessremoteparcelofland,therebynecessitatingadditionalmilesofaccessroadconstruction.Additionalvegetationclearingwouldberequiredduetothelongerroute.Assuminga300footwideright-of-way,approximately1500additionalacreswouldneedtobeclearedduringconstructionandmaintainedduringoperationofthisline,therebypotentiallyimpactingwildlifehabitat.Totheextentthatlanduse,aestheticandrecreationalopportunitiesareimpairedbytransmissionfacilities,alargerimpactzonewillbecreated.Similarly,areasofsignificantculturalresourcepotentialwillbeimpactedtoagreaterdegreethanwiththeshorterline.AgreaternumberofstreamstributarytotheSusitnaRiverwillneedtobecrossed,posingadditionalareasofpotentialimpact.Insummary,constructingtransmissionfacilitiestotheVeesiteconsiderablyincreasesthepotentialimpactofprojecttransmissionlines.8 3.8AccessRoadImpactsAtpresent,anaccessroutefortheWatana/DevilCanyonschemehasnotbeendecidedupon,andnoinformationatallisavailablewithregardtoaccessfortheVee/HighDevilCanyon/Olsonscheme.Also,ithasnotevenbeendeterminedwhichofthetwoschemeswouldhavetheshorteraccessroad.Byvirtueoftherelativedispersionofthedamsites,however,thetwo'schemesmaydifferwithrespecttotheareaopeneduptoaccessandtheresultantdispersionofhumandisturbanceovertheUpperSusitnaBasin.TheWatana/DevilCanyonschememayconfineaccesstoasmallerportionofthebasin,especiallyifaccessisfromthewest.TheVee/HighDevilCanyon/Olsonscheme,especiallyifitisastageddevelopment,maybemorelikelytohaveaccessfrombothnorth(DenaliHighway)andwest,therebyopeningaccesstoalargerarea,andfromseveraldirections.3.9SummaryIneachoftheenvironmentalstudydisciplines,differencesexistinthepotentialimpactsoftheVee/HighDevilCanyon/OlsonschemeincomparisontotheWatana/DevilCanyonscheme..TheVee/HighDevilCanyon/Olsonschemehasmoreapparentdisadvantagesthanadvantages;mostofthesedisadvantagesareduetotheVeeimpoundmentratherthantheHighDevilCanyonimpoundment.Insocioeconomicsandinsomeaspectsoflanduse,thedifferencesduetostagingareofmoresignificancethanthoseduetothelocationofthedams.Nevertheless,itisnoteworthythattheVee/HighDevilCanyon/OlsonschememayaffectmorecanyonsandwaterfallsofoutstandingscenicvaluethanwouldWatana/DevilCanyon.ExistinginformationsuggeststhatthereisahighpotentialforoccurrenceofculturalresourcesinthevicinityoftheVeereservoir,perhapsevenmorethaninthevicinityofDevilCanyonandWatana.AmajordisadvantageoftheVee/HighDevilCanyon/OlsonschemeistheimpactofOlsononanadromousfishspawninginPortageCreek;dailypeakingfromHighDevilCanyonwithoutre-regulationisalsoenvironmentallyunacceptable.Thereisevidencethatimpactsuponbiggame(particularlymooseandcaribou)andfurbearerswouldbemoreseverewiththeVee/HighDevilCanyon/OlsonschemethanwithWatana/DevilCanyon,althoughthisisnotnecessarilythecasewithbirds.AlthoughtheVee/HighDevilCanyon/Olsonschemewould9 floodlessacreagethanWatana/DevilCanyon,alargeramountoffloodplainandwetlandhabitatwouldbeinundated.Becauseofthelongerdistancetraversed,potentialimpactsofthetransmissionlinewouldbeproportionatelygreaterwithdevelopmentattheVeesite.ThedispersionofthedamsitesintheUpperBasinwithVee/HighDevilCanyon/Olsonwouldalsolikelyresultinalargerimpactzoneduetoincreasedaccess.10 4 -CONCLUSIONAlthoughsomepotentialadvantagesanddisadvantageshavebeenidentifiedforboththeWatana/DevilCanyonschemeandtheVee/HighDevilCanyon/Olsonscheme,sufficientinformationisnotyetavailableuponwhichtobasea firmrecommendation.Theevidencethatisavailable,however,whencombinedwithintuitivejudgement,suggeststhattheWatana/DevilCanyonschememaybepreferabletotheVee/HighDevilCanyon/Olsoncombination.Thecommentscontainedinthisreportwillbereviewedandrefinedafterthe1980AnnualReportsareavailableandwhenmoreconstructionandoperationaldetailsareknown.ComparisonofthetwoschemeswillstillbehamperedbythescarcityofinformationconcerningtheVeeimpoundmentarea.11 APPENDIXADESCRIPTIONOFSTAGINGALTERNATIVES .'~..~~,.P5700~14.06'.December,4,1980~fo~o~~~nsmit:bl·toTES).I..,Hutchison·'' ".r~;~;~~~:'~~P~~:~" .:.~urr~~t.SusitnaBasinDevelopmentSch'e!nes"Asreq·u'ested~·theschemescurrentlybeinginvestigatedare"sunmarizedonthe'attachedsheets.:,Please''notethattheprobableon-linedatesareestimates.at~~!s.stage,andwillbefinnedupoverthenexttwoweeks.I.HutchisonIH:ccvAttacr.mentscc:J.D.LawrenceJ.H.Hayden'P.T!Jc;-{el~(Col.)A.SimonG.KrishnanD.CarlsonR.HartV.S-inghP.RodrigueE.~l.,ShadeedR.Ibbotson SCHEME Plan 1 .(Total installed capacity =1400t·1U) Dam Site DeviL~anyon (450)DamSite I. Stage I Development Dam Site Watana (22001 Height 750 ft. Installed Capacity 800 ~~ Probable on Line Date 1995-2000 Daily Mode of Operation Peaking Separate Re-regulation Dam Possibly Stage II Development Height 570 ft. Installed Capacity __~~~ .Probable on Line Date 2010-20 No Oai1y Mode of Operatione.eakjng Separate Re-regu1 ation Dam ...:.rJ,L;;:O~_ Stage III Development i Height ft. Ins ta 11 ed Capacity ~M Probable on Li ne Date --- Hode 'of Operation _ Separate Re-regulation Dam _ ~~age IV Development Dam Site _ Height ft. Installed Capacity ~M Probable on Li ne Date --- Mode of Operation _ Separate Re-regulation dam _ NOTE:Figures in brackers behind dam site name indicate maximum water surface elevation in feet. SCH EME ~P1U!a.!.!.n..J;2,-_(Total installed capacity =1409 MW) Dam Site O~yjl.ca'nYQ!J (1.1501)Dam Site .•• Stage I 'Deve 10E!!l.ent Dam Site Hqtana.(2000L Height -2§.Q ft. Insta 11 ed Capaci ty 400 f4W Stage II Development Dam Site Watana (2200). Hei ght ,750 ft. Installed Capacity .800 ~M Stage III Development Height 570 ft. Insta11 ed Capaci ty 600 '~1VJ -~ ?tage IV Development Height ft. Installed Capacity .~M Probable on Probable on Line Date 1995 ,,Line Date 2000-10, Daily "Da ily , Hade of Operati on Pea king , .Mode of Operati on eea kj 09 Probable on Probable on Line Date 2010-20:,Line Date • , .''""No Daily . ,t10de of Operation .eeaking ,Mode of Operation'_ Separate Re-regulation Dam Possibly Separate Re-regulation Dam Possibly Wa~tanaDam raised 200' Installed Capacity Increased by 400 MW Separate, Re-regulation Dam ~N=Q~.___ 'Separate Re-regulation dam •. SCHEME -eJan 3 '•(Total installed capacity =1400 t·1\~) ~e1ght ft. Installed Capacity ~M Probable on .Line Date --- Mode of Operati on _ Stage I Development Dam Si te \:Jatana {2200} He;ght --l.§Q ft. Installed Capacity'400 t4W Probable on Line Date 1995 Daily Mode of Operation Peaking Separate Re-regulation Dam .Possibly .~tage III Development Dam Site .De\[;1 Ca OYOO_ Height.--liZ.Q.ft~ Ins ta 11 ed ,Capac;ty'600 ,~1Vl Probable on Line Date 2010-20 , No Daily' Hode ()f Operati on eea King Separate , ne-r~gulat;on D~m ~ ~~age IV Development Dam Site ------._. Separate Re-regulation'dam _ SCHEME Plan 4 '(Total installed capacity =1300 f.1W)' Dam Si te .~j gh 0 Ie.(1Z5.5)Dam Si te Vee.(?300)._, Height 725 ft.Height 425 ft. l.. .Probable on,Probable on Li ne Date .2020 -''..Line Dat~_ ..No Daily .. ,Hade of Operation .eeaking ':Mode of Operation _ Stage I DeveloEment .Installed Capac;ty .800 t~ Probable on Line Date 1995-2000 .Daily Mode of Operation Peaking ~tage IIDeveloEmen~.. .Instal,led Capac;ty .!lQO J.1W .Probable'on Line Date .2Q10-2Q. "Dai 1y Mode of Opera ti on .pea ki [lg ~t~ge III DeveloEment ,Dam Si te ..Q..1son ,(lQ1Q),. Height ._12Q~_'ft. Installed' Capacity :!:10Q_14'". Stage IV Oeve19pmen~ Dam Site ------ ';Height _..__.ft. Installed Capaci ty .~1W Separate Separate Re-regul ation Dam Pass;bly*'Re-regul ation -Dam J.Q Separate ~e-regulation Dam ~ Separate Re-regulation dam • *Olson may serve as the re-regulation dam in which case the Olson dam would constitute part of'Stage I.The powerhouse'at Olson could ~till be b~ilt at a later stage... . SCHEME Plan'5 (Total installed capacity 1:1 1300 '·U4) Separate 'Separate ,Separa~e. Re-regu)ation Dam Possibly*Re-regulationDam'Pos~ibly*'Re-t~gulation Dam ~.... ,;High Devil ,Canyon Dam Rai sed 140'"..'".,, .I'n'stalled capacity ',"Increased by 400 t1\~ ,, Stage I'Develoement Dam Site High Devil Capyon (1610) Height 570 ft. Ins ta 11 ed Capacity,400 'f4W Probable on Line Date'1995 Daily Mode of Operation Peaking Stage II Development ,, Dam SiteHjgb Ocvj"Ciln~n ,,'".',(1750) ,Hei ght,,725 ',·ft. •I •• ,I nsta 1.1 ed Capac;ty 800 t!\W,- Probable on ' , :'Li ne Date ,2000:..10,,.,.~··Daily Mode of Operation Peaki~g : Stage III Development, ,Dam S1 te •y'ee (Z~OO),;"., Heigh~425 ft. ,,......:'. ". Installed " ,Capac.ity .:....400;~1W Probable on . Line Date "2010-20 ',', """Oai ly'::" ,Hode of Opera ti..on ,Pea ki n9 'stage IV Oeveloement Dam Si,te .Ql son,(l020}_ " ;'Height 120 ft. ,"...... Installed Capacity ±Ioa ~M p'roba b1eon' ',Line,Date 2020 No Daily Mode of OperationPeakiQ9. .Separate :Re-regul ati,on «:fam ...;..:N-.o__ *O1·sonilmay.se rvei"as',th'c'::re,;;reguJ at10n ,'danf.'1n,:'wh1 ch::case:the 01 son ,dam would constitute,part of Stage I.':The'powerhouse at 01 son'. could 5tH 1 be ,bu,i.lt ata,later"stage.:'. SCHEME Plan 6 (Total installed capacity a 1300 t1H) Separate Separate Separate Re-regulation Dam Possibly*Re-regulation Dam P9ssib]y*Re-r~gulationDam'No Installed Capacity increased ~400 I~ Stage II Development No-Daily Mode of Operation Peaking Separate Re-regulation dam.--Ho Stage IV Development Dam Site OJ son (J 020) Height .120 ft. Installed -Capac;ty ,±100 HH Probable on Line Date ?020 Hei ght •425 _ft. Install ed Capacity 400_FII Probable on Line Date 2010-20, -Daily t10de of Operati on ,Peaking Dam Site lee I S~age III Development llL ft. Dam Site _High ~vil.CanYon (1750) Height Installed Capac1 ty _8.illL-t·1W Probable on Line Date 2000-1q . Dally Mode of Operati on .Pea king ~tage I DeveloRment Dam Si te ,Hi gb .Qe'Li 1 ,Ca~on (1750) Height --If§ft. Installed Capaci ty 40Q ._HW Probable on Line Date 1995 Da ily Mode of Operation Peaking *01 son may serve as the re-regul at10n dam 1n wh1 ch case the 01 son dam would constitute part of Stage 1.The powerhouse at Olson could still be built at a later stage. ~LJ..~.!...-~....!..NVJHIlM,1I NIAI_..!~~~!!!.~.!)1 VIt,CANYON DM!AND IIJNNII ~~ ..--------'----..,--------·------------~)pi'ilEiil- f"J\VirWlOlImtal (fJlfrel"efu:e~:;il'l in~JHct Atlribule _._~~~.of t.wo schemes) fcoloqical: -------------------------SCli."ne Judqed lo have Idenl ificullun the leasl polent ial impact of diffcnHlce _.Appraisal :Judgement funnel Dr: -Downstream r lstmr tt:?s and Ii d,ll.fe !!.es idenl fisher ies: Iii Idl ife: Cultural: Land Use: (ffecls I'c:-ltJl t tnt) from change:::;in wal er lIuanl i l Y and qual ity. Lotis a r res ident fisheries hahilal. lnss of wildl ife hab ital. lnundal ion of archeo log iea 1 s iles. lllundat iun of Dev il Canyon. No sitJllificanl differ- ence bel ween gel H:Hnl~S regaflHn~J effects down- stream of Oevil Canyon .. Oi ffcl'ence in reach bel ween Dcv i 1 CliO yon dam and lutU1C 1 re- requlat ion dam. Minimal differences bel ween schemes. Minimal differences bel ween schemes. Potenl ial differences bel ween schemes. Significant difference between schemes. l~ith lhe lunnel scheme cun- trollod flows between rCfJlJln- l ion dum and downstream power- house offers potent ial for anadl'omous fisher ies enhance- ment in lh is 11 mile reach of the 1'iver. Dev it Canyon dam would inundale 27 miles of the Sus ltna River and approximalely 2 miles of Dev i I Creek.The t unne I scheme would inundate 16 miles of the Susitna River. The moat senaitive wildlife ha- hilal in this reach is upslream of the lunne I re-re9ulation dam where there is no "it]tlificanl difference bel ween the schemes. The Dev iI Canyon dam scheme in adrJit ion inundales the river valley between the two dam sites result ing in a moderate ioel'ease in ifllJocls Lo wildlife. Due lo the larger area inun- dated the probahi I ily of inun- dal ing archeological siles is increased. The Devil Canyon is considered a un ique resoul'ce,80 percent of ,"'ich would be inundated by lhe Dev it Canyon dam scheme. Th is would resull in a loss of both an aesthel ic value plus the potenl ial for while water reereal ion. Not a faclor in eva ltlal ion of scheme. If fisher ies enhancement oppor- lun il y can be rea I ized the tun- nel scheme offers a positive mit igat ion measure nol ava i Ish Ie wil.h the Devil Canyon dam scheme.This opporlunity is COilS ide red moderate and favors 1he t unne I scheme. Th i3 reach of river is not con- sidered to be highly significant for resinenl fisheries and lhua the difference between the schemes is minor and favors the t unne I scheme. The difference in loss of wild- life hab il at is cons idered mod- erale and favors the tunne I scheme. A sif)nificanl.archeological site,if idenl ified,can proba- bly be excavaled.This concern is not cons idered a factor in in scheme evaluat ion. rhe aesthet ie and lo sume extenl the recreal ional losses'assoc i- ated with the development of the Oev it Canyon dam is the rna in aspect favor ing lhe lunne 1 scheme. x OVERALL EVAlIJAIIllN:The lunnel scheme hus ovel'all a lower impact on the environment. TABLE 1.2 -SOCIAL EVALUATION OF SUSITNA BASIN DEVELOPMENT SCHEMES/PLANS SocIal Tunnel DevIl Canyon---mgIlUevITLanyQilT-lVa"tan8]lle-,,'-n Aspect Parameter Scheme Dam Scheme Vee Plan Ca~yon Plan Remarks All projects would have similar impacts on the state and local economy. Potential non-renewable resource displacement Impact on state economy Impact on local economy Mill ion tons Beluga coal over 50 years ] 80 110 170 210 Devil Canyon dam scheme potential higher than tunnel scheme.Watana/ Devil Canyon plan higher than High Devil Canyon/ Vee plan. Seismic exposure Risk of major structural failure Potential impact of failure on human life. All projects designed to similar levels of safet y. ,Any dam failures would effect the same downstream populat ion. Essentially no difference between plans/pchemes. Overall Evaluat ion 1.Devil Canyon dam superior to tunnel. 2.Watana/Devil Canyon superior to High Devil Canyon/Vee plan. TABLE 1.3 -ENV.lRONHENTAL EVALUATION or IIATANA/DEVIL CANYON AND HIGH DEVIL CANYON/VEE DEVElOPHENT PLANS Environmental Attribute,Plan Compariaon .Appraisal Judgement Pliiil judged to have the leaat potential impactHDe/V ~~~:-lI7OC EColopica!: 1)Isherles No significant difference In effects on downstreom snadromous fisher les. HOC/V would Inundate approximalely 95 mllea of lhe Susllna River and 2B miles of trihulary streams,In- cluding the Tyone River. II/DC would inundate approximalely B4 miles of lhe Susltna River and 24 miles of lributary atreams, including lIatana Creek. Due to the avoidance of the Tyone River, lesser inundation of resident fisheries habitat and no signiflcanl difference In the effects on anadromous fisheries,lhe II/DC plen Is judged 10 have less Impact. x 2)Wildlifa a)l.foose HOC/V would Inundate 123 miles of critical winter rivar Due 10 the lower polentiel for direct Impect bottom habitat.on moose populations within the Susitna,the II/DC plan is judged superior. II/DC would inundate lOB miles of this river bottom habitat. HOC/V would inundate a large area upstream of Vee utilized by three eub-populetlonsof moose that range In the northeast aection of the basin. x b)Cerlbou r.)furbearers d)Birds and Bears Cultural! W/DC would Inundate the lIatana Creek area ut Illzed by moose.The condit Ion of this sub-populat Ion of moose and lhe quality of the habitat they are using appeara to be decreaa Ing. The Increased length of river flooded,especially up- stream from the Vee dam aite,would reauIt in the HOC/V plan creating a greater potential division of the Nelchlna herd'a range.In addlt Ion,en increase In range would be direct ly Inundated by the Vee res- ervoir. The area flooded by lhe Vee reservoIr Is considered lr.'portant to some key furbearers,particularly red fox. ThIs area is judlJed to be more Importont than the Walana Creek area that would be inundated by tha II/DC plan. foresl habitat,important for birds and black bears, exisl along the valley slopes.The lose of this hsbl- tst would be greater with the II/DC plan. There Is a high potential for discovery of archeo logi- cal sites in the easterly region of the Upper Susltna Basin.The HOC/V plen has a greater potent ial of affect Ing these altes.for olher reeches of the river the difference between plans Is considered minimal. Due to the potent ial for a greater Impact on the Nelchina ceribou herd,the HOC/V scheme is considered Inferior. Due to lhe lesser potent lei for Impact on fur- bearers the W/DC Is judged to be auperlor. The HOC/V plan Is judged super lor. The II/DC plan Is judged to have a lower po- tential effect on archeological sites. x x x 1.~I1U t.3 (Coni lmmdi IlOClV-."7llT:Apprais"l Judqement----_._---_._--_.Plwi l:olllparisurlfovil'Ollllllnllal Altrihulc ------------.------..----------------_.--------------------.-------------------._-..-------_._.------------------,'1";,""Judq"d (0 have (he-- least pote"Ual.impact AesUwt iC/ ~Wilh nilhcr schelllt~,lhu aeslhelic quality of hoth I){~v i t Canyon and V~e Caoyon would he impaired.fhe IlDC/V plan \'iuuld also inundale lsuuena ralls. Bolh plan!:i impucl lh~vtliley uesthcl ics.The rlifferBnce is considered minimal. DlH~Lo construcl ion at Vee DUlI1 sHe and the sizH of the Vee Heservnir,the IUlC/V ;,lan would inhel'enlly r.realc Cll~·t:esS to more wilderness area than would the lv/DC plan. An it is eas ier Lo extend access lhan to 1 imil it,inherenl access requirements were considered detrimental and the W/OC plan is judged superior.Ihe ecological sensil ivity of the at'en opened uy the IiDC/V plan re in- forces th is judgement. x OVUlAl.I [VALDA liON:Ihe 11/D(;plan is judged to be superior to the IUJC/V plan. (Ihe lower i"I,act on birds and bonrs associated with IUlC/V plan is considered to be outweighed by all _________the other impacts "hieh favour the W/llC plan.)_ NOlES; H =\'/0 lana Daw DC =Dev i I Canyon Ilam IIDC =lIiqh Devil Callyon Dam V =Vee Dnm APPENDIXJ -AGENCYANDOTHERCOMMENTSTheseconddraftoftheDevelopmentSelectionReportwasdistributedtothefollowingagenciesforreviewandcomment.Thissectionofthereportaddressesthecommentsreceivedandresponsestothosecomments.Attachment1,2,3,4and5,whichfollowintheirentirety,arethecommentsreceivedfromthefollowingagencies:-Attachment1:UniversityofAlaskaArcticEnvironmentalInformationandDataCenter-Attachment2:StateofAlaska,DepartmentofFishandGame-Attachment3:U.S.DepartmentofInterior,GeologicalSurvey-Attachment4:U.S.DepartmentofInterior,NationalParkService-Attachment5:StateofAlaska,DepartmentofEnvironmentalConservationJ.1-ResponsestoAEIDCComments(a)BorrowAreasItisagreedthattherewillbesignificantimpactsduetodevelopmentofborrowareasforconstructionofallearthorrockfilldamsconsidered.Forpurposesofthestudyithasbeenassumedthatthemajorportionofborrowmaterialwillbeobtainedfromareaswhichwillbesubsequentlysubmergedbytheproposedreservoirs.Therelativelyshort-termimpactsofearth-movingoperationsduringdamconstructionareconsideredtobesimilarforallalternativesconsideredandthereforenotasignificantfactorincomparisons.Thelonger-termimpactsofborrowareaswhichwillbesubmergedwereconsideredtobeincludedinthecomparisonsofimpactsofthereservoirsineachcase.(b)ContinuationofEnvironmentalStudiesItistruethatdetailedenvironmentalstudiesofonlytheselectedplanarecontinuinginsupportoftherequirementsoftheFERClicenseapplica-tion.Thepurposeofthesestudiesistoallowmorepreciseassessmentstobemadeofsuchimpactsandfordevelopmentofmitigationplanswhereappropriate.Thecomparisonsofenvironmentalimpactsofallalternativesconsideredhavebeenbasedonlyonthoseaspectswhichwillinfluencetheselectionofadevelopmentplan.Thereportprovidesappropriatesupportforthesecomparisonstobemadeandwillnotconsiderthemfurther.Con-siderationofimpactswhicharesimilarinmagnitudeorwhicharerelative-lyinsignificantwillnotinfluencetheselectionprocessandhavethere-forebeenexcluded.J-l J.2-ResponsestoADF&GComments(a)Page1-4(g),Task7 -EnvironmentalStudiesThetexthasbeenrevisedassuggested.(b)Pages8-26and8-27,EnvironmentalComparisonsThebackgroundinformationusedtosupporttheenvironmentalcomparisonsmadeconsistsofpublisheddatatogetherwithvisualobservationofperson-nelundertakingthecurrentstudies.Thereportprovidesappropriatereferencestoanddocumentationofthisinformation.ThepersonnelinvolvedinthestudiesareamplyqualifiedintheirrespectivefieldsandwereapprovedassuchbytheAlaskaPowerAuthority.AppropriatemechanismshavebeenestablishedforcontinuingtheactiveinvolvementofADF&G,USFWSandallotherconcernedagenciesinthedeci-sionprocessesbeingusedinthisstudy.Thescopeandmethodologyforundertakingenvironmentalstudieshavebeenreviewedbytheseagenciesandmodifiedwhereappropriateasaresultofsuchreviews.J.3-ResponsetoUSGSCommentsNoresponserequired.J.4-ResponsetoUSNPSCommentsTheSusitnaProjectFeasibilityReportwilldealwiththespecificimpactsoftheselecteddevelopmentplanandwillnotconsiderfurthertheimpactsofalternativeSusitnaBasindevelopmentplans.Sufficientinformationhasbeenpresentedinthereporttoarriveataselecteddevelopment;furtherstudyofotherbasinalternativesisunwarrantedatthistime.TheimpactofreservoirsiltationfortheselecteddevelopmentwillbestudiedandtheresultspresentedintheFeasibilityReport.J.5-ResponsetoADECCommentsNoresponserequired.J-2 ,rCI!CEnvironmenlollnformolionandDOloCenler707ASlreelAnchorage,Alm~.a99501ATTACHMENT1PHONE(907)279..c:Sf'UNIVEHSITYOFALASKAAugust4,1981Dave'WozniakAlaskaPowerAuthority333'W.4thAVenue,Suite31Anchorage,AK99501DearDave:RECEIVED:'.'!G519B1ALASKAPOWERAtlTHOP.JTYPeryourrequesttothemembersoftheSusitnaSteeringCommittee,IhavequicklyreviewedtheDevelopmentSelectionReportpreparedbyAcres.IngeneralIfounditlogicalinapproachandcompleteinre-gardstotherelevantfactorsoneshouldevaluatewhenreducingmultipleoptions.Ihaveonlythefollowingspecificcomments:1.Thelocationandenvironmentaleffectsofdevelopingborrowmaterialsitesisnotwelldocumentedandincorporatedintothefirstpartofthereport.Enormousqunatitieswouldberequiredformostofthedams,andtheremoval,stockpiling,andtransportofthismaterialcouldbeasignificantfactorinfluencingthedecision-makingprocess.2.Significanteffortsarecurrentlybeingexpendedinenviron-mentalstudyofthisregion,theresultsofwhicharenotyetavailable.Factoringthisnewknowledgeintothedecision-makingprocesscouldhaveinfluencedthenatureofthefinalscheme;oristhecurrentenvironmentalstudyeffortgearedonlytowardtheeffectsofthe"selectedplan(page9-1)"andnotforinputtotheoverallselectionprocess?IngeneralIfoundtheenvironmentaleffectsofthealternativeoptionsaddressedverysuperficially.Ihopemycommentsareofinterest.Sincerely,,,'/.)1'.(.:.(LWilliamJ.WilsonSupervisor,ResourceandScienceServicesDivisionSeniorResearchAnalystinFisheries\UW/gcc:AlCarson i')J\n,lQ..uc..t?c:.1Page1-4(g)Ta~k7 -EnvironmentalStudieslivereviewedthedraftDevelopmentSelectionReportfortheSusitnaHydroelectricProjectandmYcommentsareasfollows:ATTACHMENTReviewofDraftDevelopmentSelectionReport-SuHydroProjectJuly29,198102-1-81-ADF&G-7.002-V-Acres-1.0DATEStateofAlaskaFILENOTELEPHONENOALASKAPOWERAUTHORITYDaveWozniakProjectEngineerAlaskaPowerAuthority333W.4thAvenue,Suite31Anchorage,Alaska~1ThWTGtlJ,JR E C E , V E 0SUBJECT:omas.renAquaticStudie:coordd~nato/~!/01,1981SuHydroAquatlcStules·'~'-1-.AnchorageComment:Irecommendthewordsinthelastsentencei.e.,largegamebechangedto~game.Page8-26EnvironmentalComparison-2ndparagraph- astatementregardlligenhancementpotentialforanadromousfishand,thestatementonpage8-27EnvironmentalComparison,2ndparagraph.Comment:Ageneralobservationaddressedtothesespecificsections,isthatdevelopmentoftheenvironmentalcomparisonshasundoubtedlybeena-subjectiveprocess.Thestatementsmadereallydon'tprovideanydetailingofthehows,whys,andrationalefortheconclusionsdrawn.Ibelievewecanacceptasubjectiveprocessforevaluatingtheenvironmentalmeritsordeficienciesofaparticulardamscheme,butitwouldhavebeenahelpfulprocessforAcrestoinvolveADF&G,USFWSandothersinsuchananalysistodiscussalternativepositive/negativeimpactpossibilitIthinkthiswouldhaveledtoahealthyexchangeofideas.Theexposureofthefish9ndwildlifeorotherresourceagenciestothesamedesignoroperationalschemeslaidouttotheAcresenvironmentalreviewteammayhaveledtoconclusionswhichwerethesameorpotentiallyquitedifferentfromtheAcresanalysisofthesituation.Tosumup,wecan'targuewithAcresreportsincewedon'tknowthebackgroundinformationusedtosupporttheirrationalizationsortheexperienceoftheindividualsinvolvedinthereportpreparationthatdrewtheconclusionsonfisheries.cc:S.Zrake-DECB.Wilson-AEIDCG.Stackhouse-USFWSR.Lamke-USGSA.Carson-ADNRMEMORANDUMTOFROM: UNITEDSTATESDEPARTMENTOFTHEINTERIORGEOLOGICALSURVEYWaterResourcesDivision733W.FourthAve.,Suite400Anchorage,Alaska99501July27,1981ATTACHMENT3RECEIVED.1tJL3)1981AlASKApOWEr:':":;::-:OJ<fTYAlCarsonStateofAl.askaDepartmentofNaturalResources323E.FourthAvenue'Anchorage,Alaska99501DearMr.Carson:IhavereviewedtheDraftDevelopmentSelectionReportfortheproposedSusitnaHydroelectricProjectasrequestedintheAPAtransmittalofJune1811981.Thereviewwaslimitedtotheevaluationprocessus4dbyAcres,therelativeimpactsofseveralalternativedevelopmentplans.ofSusi·tnahydroelectricresources,andtheconclusionthattheWatana-DeyilCanyonplanisthepreferredbasinalternative.TherewerenoproblemsinvolvedinunderstandingtheselectionprocessusedbyAcresandtherewereenoughdataandinformationpresentedtocomparethefinalcandidate(alternative)plans.Therelativeimpactsofthecandidateswerepresentedinanunderstandableandcrediblemanner.Althoughenlyaqualitativeevaluationofimpactsispresented(pendingreportsofon-goingstudies},areasonableconclusionisthattheWatana-DeyilCanyonplanisthepreferredcandidateforSusitnahydroelectricdevp10pment.cc:DavidD.Wozniak,ProjectEngineer,APA,Anchorage,AY DearDavid:Thankyoufortheopportunitytoreviewthereport.TheabovecommentsaremyownandshouldnotbeinterpretedasrepresentingtheofficialpositionoftheNationalParkService.ATTACHMENT/\UG?1981RECEIVEDAlASKAPOWERAUTHORITYAUG:;iS81334WestFifthAvenue,Suite250Anchorage,Alaska99501UnitedStatesDepartnlentoftheInteriorNATIONALPARKSERVICEALASKASTATEOFFICESaveEnergyandYouServeAlIlerica!1201-03aSincerely,'-~~'./1-~1-Jt\tlPl(,)!~~-Larry.Wr19ht.OutdooRecreationPlannerMr.DavidD.WozniakSusitnaHydroProjectEngineerAlaskaPowerAuthority333West4thAvenue,Suite31Anchorage,AK99501InresponsetoyourrequestIhavereviewedtheDraftDevel-opmentSelectionReportfortheSusitnaProject.BaseduRortheinformationpresentedinthereport,Iwouldjudgetheevaluationprocesstobesatisfactory.However,Iwouldnotwanttorecommendorotherwisecommentonapreferredbasinalternativepriortothecompletionofongoingstudieswhicfwillfurtherquantifytheanticipatedenvironmentalimpacts.Iassumethefinalreportwillreflectamoreprecisecom~parisonofenvironmentalimpactsforthedamsitesunderconsideration.Anadditionalitemofinterestwhichshouldperhapsbeincludedinthefinalreportisacomparisonoftheexpectedlifeoftheprojectforeachalternativedamsiteconsiderintheeffectofsiltaccumulationin'thereservoirs.INREPLYREFERTO: BH/SZ/mnATTACHMENT5437EStreetSecondFloorAnchorage.AKP.O.Ro~1207Soldotna.Ala!>l<.a99669(907):'625210P.O.Bo>:i064Wasilla,Alaska99687(907)376·5038ilL.4//;IAugust14~19811981n[l@(";'-;\;:",o,·\I}.'.'l·./1"f\o.\'....II\1.1'")I.rJ_:Ji.rj\>~.;....".1'·/:Dr:..::..v~-04_At.thistime,thisDepartmentdoesnotendorseanyparticularplan.l-lewould,however~recommendtheSteeringCommitteeopenlydiscussthe\.]atanaDam-Tunneloptionbecauseofitsreducedenvironmentaland·aestheticimpact.Thankyoufortheopportunitytoreviewthisdocument.WeappreciateyoureffortinsolicitingSu-HydroSteeringCommitteeinvolvement.IfyouhaveanyquestionsregardingthesecommentspleasecontactStevenZrakeofthisoffice.cc:SteveZrakeDaveStudevantAlCarson-DNRSincerely,ft#//h~BobNartinRegIonalEnvironmentalSuperVisorDearMr.Wozniak:Wehavereviewedsections7and8oftheSusitnaHydroelectricProjectDevelopmentSelectionReport(seconddraftJune1981).Wefindthattheplanselectionmethodologyusedinsection8meetstheobjectivesofdetermininganoptimumSusitnaBasinDevelopmentPlanandofmakingapreliminaryassessmentofaselectedplanby.an.alternativescomparison•.TheincreasedemphasisoverpreviousanalYses·oftheenvironmentalacceptabilityofthealternativesisgood.DaveWozniakProjectEngineerAlaskaPowerAuthority333W.4thAvenue~Suite31Anchorage,Alaska99501