ML17037C156

Nine Mile Point Unit 1 - Letter Regarding a Geological Report and a Request for Examination and Submittal of an Independent Opinion

ML17037C156
Person / Time
Site:	Nine Mile Point
Issue date:	02/21/1964
From:	Ewart J N Niagara Mohawk Power Corp
To:	Sutton G Lamont Geological Observatory
References
Download: ML17037C156 (14)

Text

J0~/SNIAGARAMOHAWKPOWERCORPORATION NIAGARAMOHAWKBUFFALO8,N.Y.February211964Dr.GeorgeH.SuttonLamontGeological Ob'servatory Palisades, N.Y.DearDr.Suttori'~

Confirming ourtelephone conversation'of February21,Mr.JosephFischerwillhandyouacopyoftheDamesandMooregeological reportforourNineMilePointNuclearPowerStationonMonday,February24.Werequestthatyouexaminethisreportandrenderanindependent opinionofit.Pleasefeelfreetocomment,asanexpert,inanyareayouwishbutwewouldlikeyouropinioninthefollowing specificcategories:

l.Istheresufficient evidenceinthisreportthatthissiteisnotsubjecttoZone3earthquake rating,anddoyouagreewiththegroundacceleration asspecified.?

'"'.Doyouagreewiththehistorical seismological dataofthesiteregarding themagnitude oftheshocksatlocationoftheepicenter?

3.What'would youconsidertobetheprobablemaximummagnitude ofshockthatmightoccurinthegeneralareawithina100-mileradiusofthesiteduringthenext200years?4.Whatdoyouconsiderthecrediblemagnitude ofshockthatmightoccurinthegeneralareaduringthenext200years?JWehaveworkedverycloselywithMr.Fischeronthisproject,soifyouneedfurtherclarification ofthequestions listedherein,pleasefeelfreetodiscussthemwithhim.AsIindicated toyou,wewouldliketohaveyourreplyasearlyaspossibleinorderthatwecanincorporate itasapartofourpreliminary harardssummaryreportwhichisdueonApril1~Verytrulyyours,J.N.EwartChiefSystemProjectEngineer4

~P ALPINEGEOPHYSICAL ASSOCIATES, ING.55OakStreet,Norwood,NewJersey~Cable:"ALPGEO"~201-768-8000 March10,1964Mr..3.N.EwartChi,efSystemsProspectEngineerNiagaraHohawkPowerCorporatian 5354/ashington StreetBuffalo,NewYorkOurFile3S-714

DearMr.Ewart:

Following lsasummaryof'yopinionsbasedonacriticalreadingof'PartII,SectionC,Engineering Seismology; SiteEvaluation Study,ProposedNineHilePointNuclearPowerPlant;nearOswego,NewYork;fortheNiagaraMohawkPowerCorporation" preparedbyDamesandMaara.Inanswertothefourspecificquestions youraisedinyourletterof21February1964:(1)Ibelievethatthereshouldbesuf'flclent evidenceinthecitedreportbyDamesandMoore(hereafter called0-Mreport)thattheOswego,NewYorksiteisnotsub)ected toZone3earthquake ratingandthatthespecified groundaccelerations arereason-able.(2)Thehistorical seismological dataregarding in-tensities andmagnitudes intheregionappearstobeaccurately presented lntheD-Mreport.(3)Theprobablemaximummagnitude shockthatmightoccurinthegeneralareawithin10Dmileradiusof'hesiteduringthenext2DOyearslsH~5.0ta57(maximumintensity I,~7to8).(4)Thecrediblemaximummagnitude shockthatmightoccurwithin100mileradiusofthesiteduringthenext200yearsi,sM~7~0(Maximumintensity lo~9)~,Althoughtherecanbanaabsoluteguarantee thataverylargeshockwillnotoccurinthevicinityofthesita,ltappearstobefavorably locatedwithrespecttoseismicrisk.

4II Hr.3.N.EwartMarch10,1964Historically, onlythreeshocksofintensity I~5orgreaterhaveoccurredwithin100milesofthesita;onenear50milesdistantandtwonear100milesdistant.Therearenoknownactivefaultsintheregionanditisunderlain byrelatively undeformed lowerPaleozoic rockswithhighmechanical competence.

Seismicity inthisgeneralregionseemstoberelatedtotheSt.LawrenceValley,marginaltothestableCanadianShield,andtotheancientAppalachian Mountainsystem.HostoftheactivityrelatedtotheSt.LawrenceValleyisnortheast ofthesitewhiletheactivityrelatedtotheAppalachian systempasseswelleastofthesiteinthegeneralNE-SbJtrend.Similarzonesofrelatively minorseismicactivityarecommonthroughout theworldatthemarginsofstableshieldareasandalongmature(ancient) mountainsystems.Theoccurrence ofseveralearthquakes westofthesiteinthegeneralvicinityofBuffalo,NewYork,requiressomecautioninassumingthatthehistorical activitywithin100milesofthesitevillberepresentative oftheactivityinthenext200yearsorso.Also,Idonotbelievethatthestatement thattheseismicity maybedecreasing asaresultofslackening glacialreboundiscompletely

)ustified, since,asmentioned above,similarregionswhichhavenot'beenglsciated inthepastfewthousandyearsexhibitsimilarseismicity.

Inordertoobtainsomestatistical reliability Iconsidered aregionofradius200milessurrounding thesite.Thisregionhas4timestheareaofthezonebeingconsidered.

Thefollowing tableliststhenumberofhistorical earth-quakeswithmaximumintensities equaltoorgreaterthanthestatedvalueinthisregion:nuabar41~IntanaitV(orgreater)VI(orgreater)VII(orgreater)VII1Iftheseismicity within100mileradiusofthesitewereequaltothatofthelargerregionthesenumberswouldbedividedby4.Aconservative estimatetakingintoconsideration theactualhistorical distribution ofshockswouldbetodivideby8.(Theprecision ofthedatamakesanysmallcorrection

'I Mr.J.N~EwartMarch10,1964forthetimefactor,200yearsspanincludesmoatoftheshocks,relatively unimportant.)

Onthisbasisoneearthquake ofmaximumintensity I,~7mightbeexpectedwithin100milesin200years.Ho~evertwointensity 8earthquakes haveoccurredatadistanceonlyslightlygreaterthen100milesfromthesite.Sinceveryfewmagnitudes oflargerearthquakes inthisregionhavebeenmeasureddirectly, itisnecessary torelateintensity datatomagnitudes.

Theformula,M~2/3Io1.7logh-1.4whereMisRichterMagnitude I,ismaximumModifiedMercalliintensity hisfocaldepthinkilometers, obtainedbyHarnikasanaverageofobservations byseveralinvestigators invariousregions,wasusedforthispurpose.InaveryrecantstudybyIsacksofa300kmradiusareasurrounding northernNewDerseythisrelationwasfoundtobereliableforrelatively smallearthquakes usingafocaldepthofabout10km.Previousstudiesoflargerearthquakes inthisgeneralregionindicategreaterfocaldepths(upto60km).OntheSeismicZoningMapofthe1958UniformBuildingCoda,preparedbytheU.S.C.EG.S.,theproposedsitefallsnorthofalineseparating Zone1(tothesouth)fromZone3.Thelinesonthismaparenecessarily some~hatarbitrary andshouldbeusedonlyasageneralguide,especially nearzoneboundaries.

Theimmediate vicinityofthesiteshouldbeconsidered moranearlyZone1or,perhaps,Zone2thanZone3.Sincerely yours;;HS:GEGeorgeHESuttonAssoc.Prof.ofGeologyConsultant pprovedby:aerC.Beckmblann,President ALPINEGEOPHYSICAL ASSOCIATES)

INC~

0I THEUNIVERSITY OFTHESTATEOFNEWYORKTHESTATEEDUCATION DEPARTMENT AI.SANYINEWYORKI2224NCWYORKSTATCNVSCVNANOSCICNCCSCRVICCASSISTANT COMMISSIONCR April23,1968DamesandMoore100ChurchStreetNewYorkNewYork10017Gentlemen:

Attention:

~JosehA.PinchesInatelephone conversation withFredFoxyesterday, heindicated thatyourcompanyispresently concerned withthetrendofstruc-turalandseismiclinesinNewYorkState,particularly withre-specttotheOswegoarea.AlthoughIdonotconsidermyselfanexpertintheareaofgeo-physics,Iamquitefamiliarwiththestructural trendsinNewYorkandhavehadoccasion, withinthelasttwoyears,toplotareasofseismicity withintheState.Thereisnoindication tomethatsuchabeltpassesthroughorneartheOswegoregion.Ibelievethatseismi,cactivityintheSt.Lawrencelowlandsislargelytheresultofshallowfocusmovementresulting fromreactivation alongfaultlinescausedbyiceoverloading duri.ngtheglacialperiod.Theglacialreboundinthelast10,000yearshasbeeninthenatureof550feetintheareaofMontrealandprogressively lesssouthward intoNewYorkState.Otherstructural trendsinNewYorkStatearenortheast-southwest lineaments whichtransecttheAdirondacks, roughlyeast-west foldsintheFingerLakesareaandsouthwest, andnorthwest-southeast trendinglineswhichappearonNimbusphotoscuttingacrosswesternNewYorkintheBuffaloandNi.agaraFallsareas.NoneoftheseindicateatrendrunningfromtheSt.Lawrencelowlandssouthward throughOswegoandthenceacrosstheState,andIdonotbelievethatanyexists.DAMES&MOORENEWYORKRECEIVEDSincerely yours,cc:F.Foxg(j"IooCMIIICCG.BrougonAssistant Commissioner (Acting)ReiseIJTOICPSIWJMII9ITETRSEI.JARRMC'TMNCL,CARIJWOMITJMHJ4 lIIt I2~I'ee~IINIAGARAMOHAWKPOWERCORPORATION

.Ittllt&,NIAGARA~)MOHAWKBvvvAI.a, NEwYoRK$4203May31,1968(1)Thepassiblelinecannectio'n ofopicenters south-weotwax'd framtheSt.LawrenceRivex'alloy.

~/Dr.JackE.Olive'rIamantGeological Observatory p"-~Palisades, NewYox'k10964LtDoaxDr.Oliver:~gEaxlyin'1964wecontacted Dr.GeorgeSutton,whawasthonassoci-'ted withthoLamantGeolagical Observatory, farindependent reviewofthepreliminary geological reportpx'eparod byDamesandMooreforourNine'~MiloPointNuclearStation.%'enowfoolitisdeoirablo toobtaina,similar".independont reviewafasubsequent DamesandMo'ox'ereportentitled"SeiomicGeology,NineMilePaintNuclearPowerPlant,Noa'rOswego,NowYork."Vlehaveax'x'anged foxMr.JosephFischertodoliveracopyofthisreporttotheObservatory andxequeotthatyouoramemberofyouxstaffreviewit,asanexpert,andcommentinanyareayouwish.However,',

~~~wewouldlike'opinions inthefollowing specificareas:'~4,1~v~'t~,I~~',r'~.t'~~al,,t,~(2)Lothereanyreasonpredicated onnewinformation whichwouldindicatethatthe11pex'centanticipated m~mumgroundacceleratian previously adaptedaoadesignvalu'eshouldbechanged'l IIVehaveworkedveryclaoolywithher.Fischoronthisprojectsaifyouoryour"aosaciateo naodfurtherclarification ofthiswox'k,p)easefeelfreetadiocuooitwithhim.Wowould'appreciate areplybythefixotweekafJulyatthelatestforconsideration inmeetingsscheduled withtheAtomicEnergyCommission.

tVarytrulyyours,JNE/jfw~N.Ewax'tChiefSyotorojoctEnginoorf.

tkg~o sLamontGeological Observatory

'ofColumbiaUniversity

~Palisades, NY..10984tCabfsAddrassrLamont,Pallsados, fsfswYorkStatsCoda0'f4,ELmwood0-0000June26,1968Mr.J.N.EwartChiefSyst;emProjectEngineerNiagaraMohawkPowerCorporation

Ehxffalo, NewYork14203

DearMr.Ewart:

DrOliverforwarded yourletterofMay31tomeandrequested that;IhandlethereviewoftheDamesand.Moorereportentitled.

"SeismicGeology,NineMilePointNuclearPowerPlantnearOswego,NevYork".Accordingly

.Icontac+ed Mr.JosephFischerandarrangedwithhimameetingwithHr.FredFox.Ireceivedtheabove-mentioned reportfronMr.Foxanddiscussed theworkwithhim.readthereport;carefully andfurtherdiscussed severalpointswithttfr.FoxandMr.Fischer.Thefollowing are~comnentsthatIhaveconcerning thereport.Iagreewiththebasicargumentofthereportthat'itisnotreasonable toextrapolate therelatively h'.ghlevel.ofse~smicity oftheSt.TawrenceregiontotheareaoftheOswegosite.Inparticular, Ithinkthattheevidencefor+hecorrelat."on betweenthehighseismicity oftheNewMadridenr3.St.lawrenceregionswithlocalized fault;edstructures ofPaleozoic orlateragesisconvincing.

Thisevidencereasonably indicates that,evenifthealign-mentofepicenters isnotanartificeorisnotfortuitou tbelevetoi,'ei,sisiclty variesslgnlfi.cantly alongtbesupposedfeatureandappearstobecontrolled by'.localgeological structure.

Iseenoproblemwiththeestimation ofO.llgforthemaximumgroundaccelerat;ion".

Isuggested toMr.Fischerthatheconsider, asapossiblealternative, theeffect;sofanearthquake thesizeoftheAtticaEarthquake locatedverycloseoratthesiteinquestion.

Yw.F.'.scher inform-edmethat.thiswouldnotsigrificantly increasetheestimated acceleration.

Ingener@3.,

Iagreewiththebasicconclusions ofthereport.Pleasele~tmeknow'fyouwishfurther.deta11eddiscussion ofsomepart<eulernoints.Sincerely yours3ynL.Isacks

~vkP~