ML20002A300

HI-STORM Umax Amendment Request 3 RAI Responses

ML20002A300
Person / Time
Site:	HI-STORM 100
Issue date:	12/15/2019
From:	Holtec
To:	Office of Nuclear Material Safety and Safeguards
Shared Package
ML20002A299	List: ML20002A300 ML20002A303 ML20002A305 ML20002A307 ML20002A310
References
5021056
Download: ML20002A300 (6)

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Attachment2toHoltecLetter5021056 HISTORMUMAXAmendmentRequest#3 RAIResponses-NonProprietary

Page1of6 RAI1ProprietaryRAI RAI2ProprietaryRAI RAI3ProprietaryRAI RAI4ProprietaryRAI RAI5ProprietaryRAI RAI6ProprietaryRAI RAI7ProprietaryRAI RAI8ProprietaryRAI RAI9ProprietaryRAI RAI10ProprietaryRAI

RAI15Describethestructuralperformanceofthe24PT1DSCwhensubjectedtoaseismicanalysisthat utilizesthreecomponentsratherthantwo.

InSection2.4.3oftheapplication,theapplicantstatesthatithaschosentocomplywithSection3.7.1of theNUREG0800toperformtheseismicevaluationoftheUMAXsystemwiththe24PT1DSCcanister.

Specifically,theapplicantstatesthatithasusedfivetimehistoriesthathavetwocomponentsonly(one verticalandonehorizontal).However,fornonlinearanalyses,Section3.7.1ofNUREG0800statesthat timehistoriesshouldhaveoneverticalcomponentandtwohorizontalcomponents.Thesethree componentsshouldbestatisticallyindependent(furtherdetailscanbefoundinSection3.7.1ofNUREG 0800).Therefore,clarifyhowtwolateralcomponentscanbereplacedbyone,anddescribehowresults (safetymargins)willbeimpactedbytheuseofonelateralcomponentratherthantwoasstatedin Section3.7.1ofNUREG0800.Updateallseismicanalysesandcalculationsusingthreecomponentsas necessary.

Thisinformationisneededtodeterminecompliancewith10CFR72.236(l).

HoltecResponse:

Themethodofanalysis,aswellastheseismicinputmotion,usedtoevaluatethestructuralperformance ofthe24PT1DSCisthesameapprovedmethodusedinAmendmentNo.1(LAR10401)toseismically qualifytheHISTORMUMAXVersionMSEforstorageoftheMPC37andMPC89.Thisisindicatedin SubparagraphI.3.4.4.1.2oftheFSAR,whichstates:

ThetreatmentofLoadCase03(DesignBasisEarthquake)forstorageofthe24PT1DSCinside theHISTORMUMAXsystem,includingthemodelandanalysismethodology,isnearlyidentical toHoltecLetter5021056 HISTORMUMAXAmendmentRequest#3 RAIResponses-NonProprietary

Page2of6 tothatwhichisdescribedinSubparagraph3.4.4.1.2ofChapter3forstructuralqualificationof theHISTORMUMAXVersionMSE.

Theonlydifferencebetweenthetwoanalysesisthephysicalmodelingofthecanisters;the methodologyandtheseismicinputmotionarethesame.

TheDesignBasisEarthquakefortheVersionMSEisdefinedinTable2.3.10asaReg.Guide1.60 earthquakewithahorizontalZPAof1.5gintwoorthogonaldirectionsandaverticalZPAof1.0g.

Meanwhile,theDesignBasisSeismicModel,whichisdescribedinSubparagraphI.3.4.4.1.2andplotted inFigureI.3.4.2,isahalfsymmetricmodel(seealsoSubparagraph3.4.4.1.2andFigure3.4.25forUMAX VersionMSEwithMPC37canister).Toinsurethatthehalfsymmetricmodelyieldsconservativeresults, theappliedmotioninthehorizontaldirection(paralleltosymmetryplane)isbasedonaReg.Guide1.60 earthquakewithaminimumZPAvalueof2.12g,whichistheresultantZPAofthetwo1.5ghorizontal components.The1.0gverticalmotionisalsoappliedtothemodelsimultaneously.The5setsof accelerationtimehistories(w/twocomponents)usedfortheseismicanalysisaresummarizedinTable 2.4.5.

Insummary,whilethefivetimehistorysetsusedforanalysishaveonlytwocomponents,theapplied horizontalmotionrepresentstheresultantmotionofthetwoorthogonalcomponents.Moreover,this analysismethod,includingtheinputtimehistoriesandtheuseofahalfsymmetricmodel,areconsistent withthepreviouslyapprovedmethodologyfromAmendmentNo.1(LAR10401).

RAI19ProprietaryRAI RAI20ProvideananalysistodemonstratethedoseratesfortheHISTORMUMAXwiththe24PT1DSCs meetstheregulatoryrequirements.

TheapplicantstatedintheSARthat[s]incethedeterminationofoffsitedosesisnecessarilysite specific,moredetaileddoseassessmentmaybepreparedbythelicenseeaspartofimplementingthe HISTORMUMAXSysteminaccordancewith10CFR72.212.

Inaccordancewiththerequirementsof10CFR72.236(d),theapplicantisrequiredtodemonstratethat thedesigniscapableofmeetingtheregulatoryrequirements.Thestaffneedsthisinformationto determineiftherequestmeetstheregulatoryrequirementsof10CFR72.236(d),10CFR72.104and 72.106.

HoltecResponse:

TableI.5.1.2isaddedtoSAR.Thistableshowsannualdoseat100metersfromaHISTORMUMAX modulewith24PT1DSCCanister.Theshieldingcalculationpackageisincludedasanattachmenttothis letter.

RAI21Providejustificationtosupporttheassumptionthatthe24PTH1DSCwillremaindryinthe proposedstorageconfigurationorprovideanevaluationtoshowtheproposedsystemwillremain subcriticalunderfloodingconditions.

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Theapplicantneedstoprovidejustificationthatthe24PTH1DSCcanistersystemmeetsthecriticality safetyrequirementsforundergroundstorageintheHISTORMUMAXsystem.Theapplicantprovidedno analysistoaddressthelikelihoodofwaterenteringintothe24PTH1DSCduringundergroundstorage.

TheproposedHISTORMUMAXamendmenthasnodiscussionoranalysisthataddresseswaterintrusion intothe24PTH1DSC.Thesafetybasissubmittedbytheapplicant,andstatedthroughoutSupplement I.6,isthatthe24PTH1DSCisonlyanalyzedfordryconditions,whichtheybelieveleadstoasufficient marginofsafetytoaddressuncertaintiesintheirapproach.

Thisinformationisneededtoevaluatecompliancewith10CFR72.124(a)and72.236(c).

HoltecResponse:

TheHISTORMUMAXSystemhasanumberofbarriersagainstthepossibilityofwaterenteringthe 24PT1DSCcanister.TheHISTORMUMAXVVMlidhasbeentestedforstormwatercontrolto demonstratethatsignificantamountsofrainwaterdonotcomeincontactwiththecanister.PerHI STORMUMAXFSAR,Section10.3,itemiv,thistestsimulatesexposuretorainfallofatleast2inchesper hourforanhour.ThistestwasperformedontheinitialconstructedHISTORMUMAXVVMsand showedacceptableresults,thatwaterdidnotaccumulatebeyondtheFSARallowedcriteria.

AlthoughthesystemisdesignedtopreventfloodingoftheVVMcavity,thecanisteralsohasfeaturesto ensureitremainsdry.TheAdvancedNUHOMSFSAR(Reference[211]),Section6.1,statesthe following,Aleaktighthighintegrityconfinementboundaryisprovidedtoexcludethepossibilityof floodingthe24PT1DSCcavityduringthetransferoperationsandstorageperiod.Thisstatementis echoedintheNRCSERrelatedtotheapprovalofthecanister(Reference[212]),whichstatesthat,The confinementboundaryisweldedandtestedtomeettheleaktightcriteriaofAmericanNational StandardforRadioactiveMaterials,ANSIN14.51997andisshowntomaintainconfinementduringall normal,offnormal,andhypotheticalaccidentconditions.Thisleaktightcriteriaisbasedonahelium leakrate,whichismorestringentthancriteriawouldbeforjustwatertight.

Asoutlinedinthe24PT1DSCconfinementsupplementtotheHISTORMUMAXFSAR(SupplementI.7),

therearenoscenariosthatchangetheconfinementboundaryofthecanisterinstorageintheHI STORMUMAX.Additionally,themanufacturingandCoderequirementsfromtheAdvancedNUHOMS CoCareincludedintheHISTORMUMAXCoC,toensurethatthecanisterscontinuetomeetallthe requirementsthatallowedtheNRCtomakethefindingquotedabove.Basedonthisevaluationofthe canisterdesignbasis,thereisnocredibleleakageofwaterintothecanister.

Asadditionaldefenseindepth,theHISTORMUMAXsystemisdesignedfortheabilitytoremovewater thatcomesincontactwiththecanister.Thisisdescribedinthecorrectiveactionsforfloodingofthe coolingpassagesinParagraph12.2.4.3oftheHISTORMUMAXFSAR,whichstates,Appropriate vacuumingequipmentisinsertedthroughtheinletplenumanddowntothetransverseshells.Using thisequipment,anywaterthatenterstheHISTORMUMAXcavitycanberemoved,wellbeforeitwould challengethecanisterintegrity.

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Page4of6 Insummary,therearemultiplelayersofdefenseagainsttheintrusionofwaterintothecanisterarea, including:

HISTORMUMAXdesignedtokeepwateroutoftheVVMcavity HISTORMUMAXdesignedforeasydetectionandremovalofanywaterthatenterstheVVM cavity Canisterisdesignedandmanufacturedtobeleaktight,whichisamorestringentcriteriathan watertight.ThisdesignisnotchangedwhenstoredintheHISTORMUMAXSystem.

Basedonthesefeatures,thereisreasonableassurancethatfloodingofthecanistercanbeexcludedasa noncrediblecondition.

References

[211]FinalSafetyAnalysisReportfortheStandardizedAdvancedNUHOMSHorizontal ModularStorageSystemforIrradiatedNuclearFuel,NonProprietaryVersion.AREVA ReportNo.ANUH01.0150,Revision6,issuedAugust2014

[212]StandardizedAdvancedNUHOMSSER,Amendment0,issuedFebruary5,2003

RAI26Clarify(provide)thebasisandevaluationastowhythetechnicalspecification(TS)requirement forandofafuelremovalprocedurearenotprovidedintheHISTORMUMAXTS.

Page51oftheStandardizedAdvancedNUHOMSTSstatestherequirementforafuelremoval procedureandthenlists,ataminimum,whatitshallinclude.However,theHISTORMUMAXTS providedinthisapplicationdonotcontainsimilarrequirementstoensurethesamelevelofrigorand protectionofpersonnelthatisprovidedinthefuelremovalprocedure.Holtecstatedinitsresponseto NRCsRequestforSupplementalInformationObservation(O6)thatHISTORMUMAXcertificateof compliance(CoC)Condition8ofproposedAmendmentNo.3hadbeenrevisedtorequireaprocedure forfuelunloadingfromtheweldedTNNUHOMS24PT1DSCs(canisters)followingstorageinaHI STORMUMAXSystem.UponNRCreviewoftheproposedCondition8,norequirementforafuel unloadingprocedurehadbeenadded.

Thisinformationisneededtodeterminecompliancewith10CFR72.234(f).

HoltecResponse:

Holtecapologizesforthepreviousconfusion,theCoCCondition8hasbeenupdatedandisattachedto thisletter.ItshouldbenotedthattheboundaryoftheHISTORMUMAXlicenseiswithremovalofthe DSCfromtheHISTORMUMAXtransfercask.Ifasitechosetounloadfuelfromthecanister,those actionswouldbeperformedinaccordancewiththe721029CoC.ThishasbeennotedintheaddedCoC condition.

RAI27ExplaintheplannedprocessandactionsthatwillbetakenwhenaTNNUHOMS24PT1DSC reachestheoriginallicensedlifeof20yearsandisbeingstoredinaHISTORMUMAXsystemVVM.

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Page5of6 SectionI.10.1.1.1states,inpart,that24PT1DSCcanistersinuseforlongerthan20yearsarenot permittedtobestoredintheHISTORMUMAXperthisFSAR.Thisrestrictionofnotpermittingstorage over20yearsvs.juststatingthelicensedanddesignlifeofasystemisachangefromthecurrentHI STORMUMAXFSARdesignbasesandintroducesanewrequirement.However,noprocess,actions,or controlsareexplainedintheapplicationtodescribewhatoccurstoa24PT1DSCcanisterstoredinaHI STORMUMAXsystemwhenitreachesitsoriginallicensedlifeof20yearstoensurecontinuedsafe storage.Therefore,theNRCrequestsadditionalinformationonwhataretheplannedactions,process, and/orcontrolsat20yearsif24PT1DSCsarebeingstoredintheHISTORMUMAXsystem.Giventhe factthatthereare24PT1DSCcanisterscurrentlyloadedunderCoCNo.1029,thereisthepotentialthat thisscenariocouldoccuriftheyweretransferredintotheHISTORMUMAXstoragesystembeforethey reachedtheiroriginallicensedlifeof20years.

Thisinformationisneededtodeterminecompliancewith10CFR72.236(g).

HoltecResponse:

ADSCcanisterthathasbeeninstoragefor20yearswouldbehandledthesameasanyotherlicensed canisterthatreachestheendofitslicensedlife.Insuchasituation,eitherarenewalapplicationwillbe submittedinaccordancewithPart72orthecanisterwillberemovedfromservice,identicaltoany canisterinanyNRCapprovedlicense.

Therestrictiononnotloadingcanistersgreaterthan20yearsisspecificallytoexcludeanyuseroftheHI STORMUMAXCoCfromloadingacanisterthathasbeenstoredunderadifferentCoCforatime exceedingthelicensedlifeoftheHISTORMUMAXCoC.

RAI28Providethefabrication,inspection,test,andmaintenanceandrepairprogramfortheNUHOMS transfercask,includingtheroutineandannualinspectionrequirements.

SupplementI.10describesthefabrication,inspection,test,andmaintenanceprogramsforthe24PT1 DSCcanister,HISTORMUMAX,andchainhoistassembly(CHA90)butissilentontheseprogramsfor theNUHOMStransfercask.TheNUHOMStransfercaskisconsideredimportanttosafetyequipment asdescribedintheAdvancedNUHOMSFSAR,Section2.5.

Thisinformationisneededtodeterminecompliancewith10CFR72.236(l).

HoltecResponse:

TheNUHOMStransferequipmentisidentifiedasimportanttosafetyinthatFSAR.However,the boundaryoftheHISTORMUMAXlicensebeginswhenthecanisterisalreadyloadedandstagedinthe NUHOMStransfercaskandtransferbeginstotheHITRACtransfercask.ThisisdescribedinSubsection I.9.2.3,whichstatesthattheDSCisplacedintheNUHOMStransfercaskundertheNUHOMSFSAR.

Therefore,thecomponentslistedintheRAIquestionarenotconsideredpartoftheHISTORMUMAX licenseandmaintenanceisperformedundertheirexistinglicense.

RAI29Providetheimportanttosafetyclassificationsforalltransferequipmentusedduringthetransfer ofthe24PT1DSCcanisterfromtheAdvancedHorizontalStorageModuletotheHISTORMUMAXVVM.

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SectionI.2.5describestheimportanttosafetyclassificationsfortheCHA,topseismicrestraintassembly (TSRA),VVMpedestal,andDividerShellAppurtenance,butnotforallthetransferequipmentused.

Specifically,importanttosafetyclassificationswerenotprovidedfortheNUHOMStransfercask, NUHOMStransfertrailer/skid,NUHOMSramassembly,matingcollar,andtiltingframe.

Thisinformationisneededtodeterminecompliancewith10CFR72.236(b).

HoltecResponse:

AsstatedintheresponsetoRAI28,thecomponentsoftheNUHOMSsystemlistedintheRAIarenot consideredtobepartoftheHISTORMUMAXlicense,becausetheyareoutsidetheboundaryofwhere thelicensebegins.Therefore,safetyclassificationsarenotprovidedwithintheHISTORMUMAXFSAR, becausethosecomponentsareclassifiedintheFSARunderwhichtheyarelicensed.