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HomeMy WebLinkAboutUnalaska Outside Review Comments 1985 1fy ekce -oon Gage eS FZCLG.May tnPaanbreee.BE._ee _deotogt%and Engirleeriiig.gtgdies for oe LaeDarweaeeeseifGéothernalDeveloaloebas}aska Islan John.W.Reeder*,Michael J.Economides*,and Donald R.MarkieGeophyse"cee (7*State of Alaska Division of Geological and Seopheytcat Surveys,UU1S A5 'University,of"Alaska,U.s.SeAsy |'and ne State of 'Alaska Division of baerey.'Rs ae ate Aan aan De ane -_Sa7"and Powerr Development,U.S.Age - u ae.Geothermal resources "tnvestigetions om Unalaska.Island have:focused on ."Hakugktn Volcano and the Summer Bay region,.12.kn and 3 ko respectively .7 from 1 the.'Sonaupdty'Enowa'as3 Unalaska.In.total,"8 funarole fields”Te SETS aatepc*have been located in the.-Makuskin Volcano.Fegion.Large hydrotheraal a Reena Reeeereservoirs)having temperatures inexcess of"150°C and extending to.Oa TSeeaeeSRTayEaLyoneoptsPytenes"depths of about 2 kn}are suspected"to exist An the region,narked by.coe -i ce i -sli Bass,55 :cathefumarolefields'on the southeast flankfe)Makuskinn Volcano. .INTRODUCTION oO ie A oe os < Unalaska Island is part 'of the "Aleutian arc"which consistBee «: Aanergunsofmunerous-: volcanoes where at least 36 of these voleanoes,including the MakuskinVolcano'of Unalaska.Island,have been reported active since '1760 as"ReptreportedbyCoats(Esict).-Such volcanic regions,having shallow"magma bodies,and deep tectonic 'fracture'systems,'represent,a vary:"favorable'setting 1 for the 'existence of!Large |geothermal reservoirs. reweg"onthe topand on the south flank ofMakuskin tocarmy,Beeves et aa outer:"continental |shes bi,.cael re >gesVand nine production..:"Present P ak denandabyi,year 2000. " White a sizeable portion of the island population appears to be "pro--a Aes development,'there are prominent forces that are apprehensive.Independent of any devélopuent ;Unalaska needs to develop an inexpensive,reltable supply of energy.Geothermal resources can play an importantpartinUnalaska's energy picture,and.could be the key to total_energy"self-suffictency.9 =me 7 eee nen pels ae ".FUMAROLE FIELDS”- a a.we <40 AL el They were arbitrarily,numberedfor identification purposed ino a clockwiseLondote!oo Sy bo aS a Sh,:direction;wherethe 'Location.of these,funarolefields"are "shown 'inPopests-pe Ne aera ae 5 a et "ye :*Bee figure 1 .and14:"see :These 'Unalaska funarole,fleids vary in character.and 'dimension.Fumarole Loy .a ge Oe fae oe.we a Fa >poly e 'A .re ".Be .wn -"shown in Fig.a.nya2consist of'fumarole activity:andtopeswarm.ground covering a.region”"about °1 ka.Jong and.up:to"400 m1 wide as-shown tn Fig.33.'a Fegion consisting,also of outcrops ofhighly,,Set Los wre .Fe eran Faget oohydrothermallyalteredPlatonicandeetavolcaaicrocks.eumeroieaeex'consist of'fumarolie 'activity.and.warm"ground 'covering a-"regionese01aNBRStaaaeeanBNaeteWeeeneabout.300 m=tong and about (450)m wide ;a_region.also»consistingof,"Sipe lovg;Being located along a stream and §a."Yateral moraine.'Ese,onoe ey ary gale EEC ow. 90 m by 90 m region of unaltered volcanic beccla.A fairly large andnoisyfumarolefieldonthetopofMakuskinVolcano,fomernte fieldno.arin 6 occurs mainlyin a 100 m diameter region as shown in rigs @ near «asnalldomeofunknowncompositionandwithintheremainsofasmall oe |Sts cinder cone covered in part with sulphur deposits.This field occurs in the 3 km diameter ice-filled summit caldera of Makuskin FoLeano,..A ann es Bee ed aoe eS toene Mey eT aweé"signs of subsurface"thawing."Field 1NO.8 consisof minor fumarolic.> ?4 we ke .'a"aceavdty «and hot 'rock positioned ¢ontop.of a"emall knob:'Located.just”hee Coke *oe,.ve rrr Te saraa.1")nrrt*oOaer:Beo,tr'r+OQ:fete]be,foSD:(hhOYle}pb®|e"iela 'nod.8occurs'"in a regicd of unaltered"a io "8 SatSdaggbasaltsthathasretainedtheir"constructional forms.In\general,somepressurizedfumarolesoccurin'the fleld NO.A,N06 25 'NO.3,and TNO.ech orane nage 3aagbut:"highly pressurized fumarolés''occur in the fumarolé 'fteldaoe 5” a and no..6.. s "sodas”"peer bocetee*_o E =re1Sale/sesaebenees /eutmace waters:that.are:"ean150°ce'maximum 'temperature,s hydrothermalsystems.eeath anwee,on (ReG,8 ee ge-rolemac area elsewere as deseribed by.Mahon et al.7)lh theco eSaaon .a :wea tee.oe meteoric waterswhich,have been:heated by.a:vapor-dontnated nydréthermal:"Riis goed.ces Bone ay lhecoy ey 5 ESS .System generated from high temperature'alkali chloride waters at greater”by ;'Mokushin tes 'analyses:ue °depths Tn|addition thesd ekoskta water conat yess,fecnuse the:percentagea ee -atitefent funsiole.fields,'indicate the.possibility.that'severalpee eent ne os(uae sph2 esigp:tists eB on ."arideste ccna Makushin ean Tee i cae repsaseparatehydrothermal.systems,exist.in 'the Makuskin Volcano region.2.0 oo GEOLOGIC SETTING -7 CR he .ee -Une lacks .arya Ss *-_The rocks of Uaatska Island consist of an older group of altered ©SP EE -os 7 -Unalas es Dos.a,sedimentary and volcante 'rocks designated the erste Formation by rePrewesae ou._Brenes etal.(Ref.2),a|group of plutonic 'rocks "intermediate in age, ee and a youngergroup.of unaltered volcanic rocks.The rocks of theigre5at a wnatalydaring'the "eaplacenent oftheS plutonic 1'bodies."The regionoe .belonging 'to the'Undlaska Formation whereas0 uaattered volventes make UP.Meku sh;n_the Makuskin volcano andmost.of 'the rock exposures,to the northwest | ye :ne eee easnee.3 has been extensively iatreded byy platonte bodtes :of:abbro endfor "Convection _°s .connection atleast near;the groundSurface, woesnear'vertical fractures |on the northern5 boundarty ofthis pluton otrtkes eoswas found to have 'such,a strike-slip component as based on observed wae te nye fees de tee 5 :aeSeveralnearverticalfractures,striking between N 4o°w and N 70°W and”Pm ene appearing to be normal faults,were found near the vicinity of the ean Vee ." .fone 2 OR ny.LENfumarolefieldsasshowninFig.1.-Two,of these faults,which strike about N 60°W and bound the field no.2,extend nearly the entier length a7 of the northern part of 'Unalaska Island;a distance of over 36 kn.These two fractures:are active since they.disrupt 'soil horizons.Due:ne:.Se eae B78 etna”te roa a ies wee a er xto'the-underthrusting of 'the ©'Pacific+plate wader ¢the North American oe4ce |conpteebdonel atresses in)the"asection of.'plate'¢convergérice:wil exist)-(Res,10)es i"fn the-are 'region as 'indicatéd by Nakamura LRA Because the'notion ”__of convergence of the Pacific and North:American plates at'Unalaska is._'approximately.in”a N 45ew'direction,|these 1nearr vertical"fractures arehavebeenne"ceteiagly suspected to "fr caused by'these'compressional'tectonic.stresses."These fractures,éveit 'though 'they correlate with 'most "of 'the.fumarole |2 os.4 :Aa oncid4Craiescansweesces'fields,do not 'appear,to influence ,the 'actual Surface 'configuration of.3 'for byarothermal convection;that fs ob eastnot near 'the,"ground”oenN eens8)determined, aeof:N.60°0 where theexpected «azimuth"should be about.N145°We TE,'the.'moe coats tee,ke nas Mey oe ee eal Oe ey Meg "tre wae i 7ooexpected.'N ase We azimuth isthe.actual one,then the recognized fractureStriking|'about 60°.Wo|should contain «astrike-slip component.As |Faa”dn what es :ote"shown 4'In.Fig.1,one.YN.60°.w striking,fault,"in'the coumunity of Unalaska go.It is suspected that large hydrothermal convective systems exist inaYemenortheastorientedzoneas,roughly marked by fields noe 1,no.2,no.3, ""..and no.4.Recent lava flows.Goes,flows that 'still retain details ofaFeseroene:wo their constructional forms).can be "found northwest of this zone as represented by the flows from the upper reaches of Makushin Volcano and from the prominent rift zone near Point Kadin,portheast of this fone.coewaePe aneeroepee tet trtition seme a-within | ee ae ane Lat eR Meee eteInafactyag.unaltered volcanicFocks have'been recognized ;as 'being "have 'occurred in this 'region:for.'the last 'three million years as based”anradsoretric. on the 'known range,of"'Bedionetric.age,dates for the"unaltered voleants-Re$12)”om).for 'the Aleutian Islands '"eithceurredeither because.the Joel p 'redabl"greater Shan f a to'the venweat hisaoYaan: vida ar :ei ad a 2 For.en awest,"northwest;and north,"couldbe.the heat.'sources.teany:large.ae te ee'bydrocnerna,couective systene 'in.'this:northeast i Be -er eres n In contrast,any hydrothermal convective systems linked to fumarole*etyfields.no.5,no.6,nos 7,and NO.8 are Suspected to be limited to.shallow zones where any.heat sources would also be atshallow depths.- Such shallow heat sources might be due to the existence of recent .:,;-oo, fete we.se 'surface voleanie flows that still contain heat as suspected at fumarolevetela§no.BeSuch shallowheat sources "also might |bedue to.thecooling -ar :SPS a!of"Shallow 3magma "bodies as'reflected by the domi”'infield NO»1%as$shownwtaedBop eS oe iBlastare.=typleally |porous'basalticrocks «Any.)heat contained.in. a ee"!But,>seer convective-systens,might exist in the:fractured « ,funarole,field regions'of the Makushin.Volcano exeépt at Summer BayzyaoaawhichisosoenearthecommunityofUnalaska”shown 4 Figure.ne This particularRef,tz?se hensbe wetTeeeenot:atpresent showan Bai b ne SeeSpey aio 2Ein RRR 'found throughout |a sae ae Gad gontral:aleutiat sore roan So Pew sea8 eo ae ee ee Bo oe oo -eas Cowes ete hg early series consisting of a marine volcanic and sedimentary sequencethathasbeenmetanorphasedtoagreenschistgrade,a middle series. rs of plutonic rocks,and a late series consisting of an unaltered sequenceFesaomeoflateTertiarysubaertalvolcanic.and sedimentary rocks as described(to,by Marlow et al.,).In addition,the quaternary calc alkaline an *Riehl-magnatism found in the Unalaska Island is'similar to"magnatism found °within the central 'sections "of four'najor are segments asFecogatzed:2 Hn or we eyedet.ale,whnichmake,UP a'good part of American plates:sould'aso be"'expected nearthé Quaternary.voleanié.centers.throughout |the Aleutian,arc,where,such fractures should have"strikes.similar to the directign'of.maximum "horizontal compression'as.nonQs."determined by.Nakumura SeeBLPLANOFherion D.will.beeequtred to:the ©cogs teatsn /.. "aévelopaent Of.anyamakeanyinitialestimates:'of.the.nature:andPaEmota'this reg rensP=Eshydrotheraalreservolrs¢”Tt.is.recommended here.that -seothernal arilling aeparget :zone a in abanaence ere.Aaa aaa ne eerBa4sShownreWG.S "Te Fs-"expected hat this ar Sen woelofshoveasLhelogistien/base Ser any pilannecl keithing ,TheSurtece|of the a@instey,rs Currently ia [rer condition buat rr cent 4eupgraledtereceive'fees Eras Sec in @ Sheet pecied of fine |If any serious deep geothermal drilling is to be undertaken in the._.. _-s..Makushin Volcano region,an access road would be required to the drill site from the coast.With respect *to the 'northest,oriented target | .zone,there are only three potential road.approaches;i.e.,the Glacier =: Valley,the Makushin1 Valley,and the Driftwood Valley as shown in Fig.a ieOf thésé,'the Glactal valley and theMakushin 'Valley.approaches aa _Zwould require,especially |inthe,upperreachesof the Makushin Valley,”a os-the "routing of the road across.'large!rivers and,through fairly deep |canyons .Incontrast,aa "good'part.-_ofthe 16kn Driftwood route as _nnshown'in Fig.8 would 'be athigher 'elevations;avoiding'canyons and.te major drainages.athis 'route;one.bridge would be 're uired at point -Sryte ae,A and extensive bedrock"piasting would be.'required «at.point Be An )"arenes a pee .existing 'road."connects.'Driftwood |'Bay.with the'Sugarloaf cone#ache7'this road.is3 washed oout at numerous places and.considerable'repairs .".7=.;oe ;- ewould.be |necessary to make it possibies\The 'cost |for'"putldingTaSSaadSon,rebailding the Vinstieg'aroadtositeseashouldbe.under.2 piliion 'Ue Sedollars,Table.la. "and najor,bridge 'Constructions."Hovacliiy forther surfaceexplorationyoeaenecmnlly.Des tes . oY. . :would |be 'conducted "to."determine drillingtargets,but:Togistical us oSiteCislocatedataioeastartsPEtesaeswe"van elevation of about 600 neters:"above sea"Level;a 'gite.that would 'be.-coe e sod pack vies ...Tas :_engelted 3abet of the:time”the fanous Atedttan\fog and,couldexperience aeere PETRTTSMTG<The"main euphasts suggested bhere for:further,exploration'is.deep #5.APR,eo,"exploratory:drilling.-Such a"recommendationShould |not:be considered.ee."unusual espectally,when'considering,the:'difficulty andexpenses” Ps .sae geinvolvedinundertakingstandardexploration *surveysdue to Aleutian «.Sake seeweatherconditions and due'"to 'the remote and 'Tugged terrain of theMakushinVolcanoregion.Such a "recommendation is also consistent with =a+°the general exploration and reservoir assessment plan suggested by -Re5,17)Reeder"et al.Reis=10)for site-"specific investigations in Alaska.Such a deep drilling emphasis'should not tule out 'other exploratory aeoutveyeconductedPriortoasaforaoringdeepexploratorydrillingeaoytabsthan200,'meters aa 'obtain |temperature gradient.andeven.rock.permeability 'values in the”wwe hieUnalaskaFormation.and in plutonic bodies found in the region southeast |aeMakushin Volcano.”Low temperaBaeFi arate7recomended 2 ¢drilling;where,such |asurvey."would”be geared |toward dettning |thex7-ender!analtered,veleaniccocks | iesetvoirs poring the 'agiiling operation;i ceable "got eaogrebshould |be operated.near.cr ey,not:vat).the.artlltag ©'operation,for.volcanic | arrDEVELOPMENT ECONOMICS sew rr Geothermal energy is "location intensive”.©,Hence "unlike fossil fuels ae :conimit "7,there is”a need for the2 benefitfed markettobe in close bromine wiwith |os .the resource.Unalaska Island,with its relatively sizable population.and a,large fishing andprocessing industry presents”'an attractive!target .ayforgeothernaldevelopnent.A report.by.the UeS Bureauofand Managenent"{ReS,18)eae|Sastry projects an electric 'utility 'demand of50,MW.in the -year,2000 »oes ee neeee 'under a base case.Anticipated offshore"petroleun explorative in theBen.GCA feeBergingwillincrease.the demand.The”same "BeheM,report projects aSere Bet demand of 56 Mw Pra moderate ofl and gas leasing in 'the 'outer coitinental ©Me cane .poset SED pe”.oe reypectvens 5 OSES ao foto O"shelf proves successful.Their*Project appearg <onn Figs 2 'osstea on thestan rocnea a sitet of eaatots, a a :ag ON estaecpptee|esaeapeakof6000Yaborerssduringthe,fishing |sensed Phe er1SPEONRRBa foe eR "at this time electric power is generated by the city and by eeach of theprivateprocessors.However,consolidation 'to a power source likely.ifanattractivesinglesource"(such as_geothermal)becomes _available.-:.Neat dn o Le :eS re vee ag? 4 ° oer Sigehae "mes Economides et al.1 Sosonsed an analysis of the island logistics and the.os power,plaat economics +eee ae re ee nese!_ae sitetthe the:abandoned ailitery airstrip af DiLEE woodBay.pag Bay"etvarheie in the-tnited-trator aynew:energy.venture 'needs 'to be conpaned Table.1b _Tepresents a best:extimate |"scenario:for®'a,1.30 ccs"Beothermal 'powerbyEconomides ef af Che$:49 : output *'sites is "presented 1in Figs, Laks, The picture becomes even brighter when one contemplates future prices for eet cee vat petroleum fuels. "S ees :: C5,19 PadTheanalysispresentedbytheEcononidesetampresumedapricefordieselthatwouldremainconstantinrelationto1981"dottars.ae is|however,highly optinistic;a fact that makes geothermal energy _CONCLUSION© Any geothermal resources under the southeast flanks of Makushin Voleano wae ON Unalaska;Islandappear.to be of 'the sizes and types.that could.be-ee os"developed for electrical'energy production.Such development also.+het .BeBn.=,. om eappears|to 'be"economically attractive Fea the:Fades, oe"that 'need'to be addressed by.the logai'estate 3local 'interest .-rOUPS . aie ee we a Fe REFERENCES 1.Coats,R.Rei "Volcanic activity in the Aleutian Arc".U.S.Geological2"gutvey,Bull.974-B,1950,47 pp. a 2.Drewes»H.,Frasers G.D.,Snyder,G.Les Barnett H.G.,Jr.i ."GeologyofUnalaskaIslandand'adjacent insular shelf,Aleutian Vo jemi"Islands,"Alaska.”U.S.Geological Survey,Bull,1028-5,1961,pps Sage = -Prograns and setracts, Vapor-dominatedhydrothermal manifestation'on|UnaLaska "Reeder,Jee: Fs eeepNagent3ve web"File Report, 7 &=capeeo =ore .?ae "sfflesg.fn th-leatran AOC)Aoéke Ls.'-of Lo Bechere$Lake”ofn;Transections,Geo Chermal Reseurce C..aer/UPB f°Banal ee,Clouston )Texas,W547,|CCl,25-27,9&1),Pavecs,Cals$orar a,v5.SSGeothermalResourceCouncil,ve 5 (9&7,fr:MOTHS Qe cee etMahon,W.A.,Klyen,L.E.,and Rhode,M.:"™Neutral sodiua/bicarbonate/sulphate .wheesulphatehotwatersingeothermalsystem."chinetsa,'Ve W,"noel (serg no.64),March,1980,Pp.11-23.'a oe _oe Perfect,MoRs,and Lawrence,J.Re:"OxygenAsotopic evidence for_OSE es"meteoric water,dateraction with the 'Captains Bay,pluton,"-oe -a i ae "AB.ie a_Mléuttan Tslands.7 "Earth and1 Planetary Science Letters,-#veeaVe450.1979,PP:"16-22. tc 'Nakamuram,K.:"Voleanoes 'as possible indicators of tectonic stress _5 corientat{on--prinetple |'and1 proposal.”Journal Volcanology |a)and Geothermal 'Research,ve 2,1977,--PP+I 16.i : |"volcanoes.as possiblepeMeoetio:wea BoeAndicatorsof'tectonte,stress ortentation--Aleutians |a ot aaaoobaAlaska,”Pageoph,Fe: afore UAG R-213,1970,182 Pe (fe OS Ielands with»paleoaagnettc'data,from'shenyaand1 Adakioete foeaeaia"Aslands."University of "Alaska Geophysical.Institute,ae,Me Atal wes oat atWer""Initial assessmentoF 'thehydrotheraal £resources.ofon"ade:Yen" eonSIAEOct'z'25-29,1981).'Davies;'california;U:StA.,:Geothermal Resoureg ¢Council,we 5,1981,PP.BEI oy oe a4S.Marlow,M.S.,Scholl,D.W.,Buffington,E.C.,and Alpha,T.R.: Pee ne "Tectonic history of the central Aleutian arc.”Geological Society America,v.84,1973,pp.1555-1574., - .te, Kz Kay,S.M.,Kay,R.W.,and Citron,G.P.1 "Tectonte controls of Aleutian .arc tholeitic and calc-alkaline magmatism."In:,aa a -oye Abstrats,'ser raveer Sysposten Are Volvanism1 =(Toyo":ee /;oo "ad tatone,Japan Age,28-Sept.59,1981),'The a - oo oe Interior,ae pon ee eeEconomides.an "ss 7 _PetroleumEngineers)of AIMEi (ails,'Texas,U-S.AHy,ae aenns: PR vet LF"21-24,"1980)»,'SPE.of "ana,sre.9272,1980,"15°'DP Bureau'of Land Manageneiit "St_Peveloment Seenarton Local:scclBLpis Syetncs hagaers, ¢&,Economides,M.J.,Reeder,J.,and Markle'D.:"Unalaska geothermal..ee _ woe :development."In:Proceedings,Third Annual New Zealand OS ee Geothermal Workshop (Auckland,New Zealand:Nov.8-10,© 1982),University of Auckland and the Zealand Administry sown og Works,1981,ppe mc 8 Benes ne i ray yee ga ete * =ene -me oy folate ce oe 7 Tats .# .« Table 1.Capital Investment fi 2 30 col|Geothermal Power Plant nalaska Island - ITEM NUMBER DESCRIPTION COST 'Well So ,6 |8,000 feir7 3/4"diameter assumed 50%dry wells)$12,000,000"Piping -(|.3,000 ftes 8 'diameter pipe,installed ;250,000 Road from Se od ae -_ Driftwood ""=)3000 ft.of serrvice road,'18-ft-wide gravel,at .=ee $200,000/mile $2,000,000 Generator re oe 35 MW maximum Capacity generator,installed $20,000,000 'Transformer SG -oe Station 1 -.55 MW at $30/kW,installed oe $1,375,000 «Transmission...ee eam _-nn a aan5tt11milesoftransmissionlineoverland(helicopter ospee>-Anstalted);5 niles|underwater,$100,00/mile *$1,600,000Road>'along we ;Transmission'line a3,200,000 [.$40,385;000 (Contingency .”Total to be deprectated -top te $4,038,500 | $44,423,500:- /wyb+BuROMETEAS Mokushin Boy ULES Portage Bo MAP SYMBOLS <4 ao Fault:dashed where spproximate _@ |Fumarote field. . °Warm and/or hot springs *Recent volcanic vent sev?gyavygt Uneitered volcanic rocksc j . Plutonic rocks Unateska Formation C3 Volcanic caldera' 'Map location'on northern part of Unalaska Island Np a Re) {-sf ee 7 farmereoeerag seepageeneee seems * ek eee Let eg etscayre +ITSETS eee Pen cereee Se OE,sh we > 7rhe;ra +eeAar, wePo pe me faxSASPRe iow, 12 vd aN : iy hr aba ietaSh rer A mt: : 7 Py N he' at _ 3 S * de Caae ie ae ae ,ei. er Ce, "par Sa Nehfas FE A 4 f 2 Be wx. , a Oe : ' * wet y oo eeeegoomens nt eeFeeatfettie wr, yeeet _*.wsMt SF myv Cg SS nea. LOD adensaeyaealoralSITS2 gant 4 poeremlq\ LxSeen Wnaaao\iitUOYan:Ne¥¢vugeard4NOSLery "." x "he Wid3aNeo YSoWarr, Pont Tebentot DRIFT WOCR Fesncp Font Gis qe . vyWA ty mu Saath NETO eh <>. teeoffers ibei<i5 rdme esHie Pen eeeeetaeeeeyengtFroshaan cae:p ae'AINEattiyg?Wr Le niepaLEae ¥is st 60 ftoO©©'Powerdemand(mw).'-©-.t0 "0 .1980.oNO°BLM(Mean scenario) ".-BLM(Base case) PAB gd a ;__2 | | A885 _,1980 1995 2000 |Year Figuree 7.Electric utility demand forUnalaska Island .(from BLM,#¢6@ H--.Kee 17) Fraere 7 gaun»+40 Rateof.return(%).i Soya on Unalaska.Island,itwel y --Geothermal power plant 2 -Diesel power plant 0 Tg a db ee101520.25 (30)35.4 .|Plant'capacity(mw)!;7 :Figure.Bw Comparative,economicsfor geothermal anddiesel power plants l. 2. 3. 5. direction.Photograph by John W.Reeder,1980 :;oe "Grillingsite and access road,view «of the Driftwood Bay 'airstrip.taken during'a landing approachfrom: J 19BLs won ee'Electric uttitty 'demand 'for.Unalaska Island from a BLM report "(Ree Generalized geologic map os the northern part of Unalaska Teland.The main part of fumarole field no.1 as viewed looking ina|northeastern nesdirection,Photograph by John W.Reeder,1980., The main part of fumarole field no.2 as viewed looking in a southwesterndirection..Photograph by John W.Reeder,ite)ae wars ey .LIS eo vo eeeFumarolefieldno.6 as viewed from the air looking ina northwestern Topographic map of the Makushin Volcano region 'showing the location of.tefumarolefield,hot and/or warm Springs,and a 'Proposed deepexploratory. .Fhe araetheBeringSea.hofosraph-by Michael 'J.Economides and John WeReeder,” ty Comparative economies 'for "geothermal'anddiesal power 'plaats on Unalaska mlIsland.oehbg ge e-a Ce.re aa vo