ML17331B232
| ML17331B232 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 02/15/1994 |
| From: | FITZPATRICK E INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG |
| To: | MURLEY T E NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML17331B233 | List: |
| References | |
| AEP:NRC:1168A, NUDOCS 9402240306 | |
| Download: ML17331B232 (16) | |
Text
ACCELERATEDDI'lp~pt~IUTIONDEMONSTIONSYSTEMREGULATORYINFORMATIONDISTRIBUTIONSYSTEM(RIDS)ACCESSIONNBR:9402240306DOC.DATE:94/02/15NOTARIZED:YESDOCKETgFACIL:50-316DonaldC.CookNuclearPowerPlant,Unit2,IndianaM05000316AUTH.NAMEAUTHORAFFILIATIONFITZPATRXCK,E.IndianaMichiganPowerCo.(formerlyIndiana6MichiganEleRECIP.NAMERECXPIENTAFFILIATIONMURLEY,T.E.DocumentControlBranch(DocumentControlDesk)SUETECT:ApplicationforamendtoLicenseDPR-74,deletingTS3/4.3.4,associatedbases6associatedindexlistingsforturbineoverspeedprotection.DISTRIBUTIONCODE:A001DCOPIESRECEIVEDLTRENCLSIZE:TITLE:ORSubmittal:GeneralDistributionNOTES:DRECIPIENTXDCODE/NAMEPD3-1LAHICKMAN,JINTERNAL:NRR/DE/EELBNRR/DRCH/HICBNRR/DSSA/SPLBNUDOCS-ABSTRACTOGC/HDS2EXTERNAL:NRCPDRCOPIESLTTRENCL11221111111110RECIPIENTIDCODE/NAMEPD3-1PDNRR/DORS/OTSBNRR/DRPWNRR/DSSA/SRXBOCLFDQREGLEOlNSICCOPXESLTTRENCL111111111011DDRDNOTETOALL"RIDS"RECIPIENTS:DDPLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOMPl-37(EXT.20079)TOELIMINATEYOURNAMEFROMDISTRIBUTIONLISTSFORDOCUMENTSYOUDON'TNEED!TOTALNUMBEROFCOPIESREQUIRED:LTTR16ENCL14 0~~t.4 IndianaMichiganPowerCompanyP.O.Box16631~Columbus,OH43216N'EP:NRC:1168ADonaldC.CookNuclearPlantUnit2LicenseNo.50-316DocketNo.DPR-74TECHNICALSPECIFICATIONSCHANGEREQUESTTODELETETURBINEOVERSPEEDPROTECTIONREQUIREMENTSU.STNuclearRegulatoryCommissionDocumentControlDeskWashington,D.C.20555Attn:T.E.MurleyFebruary15,1994
DearDr.Murley:
ThisletteranditsattachmentsconstituteanapplicationforamendmentofthelicenseconditionsandTechnicalSpecifications(T/Ss)fortheDonaldC.CookNuclearPlantUnit2.Specifically,thechangeproposedinthisletterdeletesT/S3/4.3.4,associatedbases,andassociatedindexlistingsfortheUnit2turbineoverspeedprotection.Theturbineoverspeedprotectioninstrumentationtripstheturbinetopreventgenerationofpotentiallydamagingmissilesfromtheturbineintheeventofalossoftheturbinespeedcontrolsystemoratransient.WebelievethepresenceofaT/SfortheUnit2turbineoverspeedprotectionisinappropriateandunnecessaryforthisbalance-of-plantsystem.ThisviewisconsistentwiththeMERITSprogramofNUREG-1431whichdoesnotincludeatechnicalspecificationforturbineoverspeedprotection.ThisT/SchangerequestisbeingproposedtoincreaseoperationalflexibilitytoconductturbinevalvetestingandmaintenanceandtoeliminatethisT/SdifferencebetweenUnit1andUnit2.ThisT/Schangewillnotsignificantlychangeourtestingpractices.Previoustestingresultsshownosignsofadverseturbinevalveconditions.WeintendtocontinuetotestUnit2andmaintaintheturbineoverspeedprotectionavailableduringpoweroperation.ThisT/SchangerequestistoproviderelieffromtherigidityofthepresentUnit2T/S.Xslyp0940224030h9402i5PDRADQCK05000516gp.PDR..
IIV Dr.T.E.Murley-2-AEP:NRC:1168AAttachment,1providesadetaileddescriptionoftheproposedchanges,thejustificationforthechanges,andourproposeddeterminationofnosignificanthazardsconsiderationperformedpursuantto10CFR50.92.Attachment2containstheexistingT/Spagesmarkedtoreflecttheproposedchanges.Attachment3containstheproposedrevisedT/Spages.Inaddition,thisisourfirstCostBeneficialLicensingAction(CBLA)submittal.WeneedtoimplementthechangeintheupcomingUnit2refuelingoutagecommencingAugust5,1994.ThelifetimecostsavingsassociatedwiththisCBLAare$1,800,000asdetailedinAttachment4.Webelievetheproposedchangeswillnotresultin(1)asignificantchangeinthetypesofanyeffluentthatmaybereleasedoffsite,or(2)asignificantincreaseinindividualorcumulativeoccupationalradiationexposure.TheseproposedchangeshavebeenreviewedbythePlantNuclearSafetyReviewCommitteeandtheNuclearSafetyandDesignReviewCommittee.Incompliancewiththerequirementsof10CFR50'1(b)(1),copiesofthisletteranditsattachmentshavebeentransmittedtotheMichiganPublicServiceCommissionandtheMichiganDepartmentofPublicHealth.Thisletterissubmittedpursuantto10CFR50.30(b)and,assuch,anoathstatementisattached.Sincerely,ee,E.E.FitzpatrickVicePresidentdrAttachmentscc:A.A.BlindG.CharnoffJ.B.Martin-RegionIIINFEMSectionChiefNRCResidentInspectorJ.R.Padgett Dr.T.E.Murley3AEP:NRC:1168Abc:S.J.BrewerD.H.Malin/K.J.Toth/C.C.SavitscusM.L.Horvath-Bridgmanw/oattachmentsJ.B.Shinnock-w/oattachmentsW.G.Smith,Jr./S.H.SteinhartS.P.Hodge/J.D.Benes/G.D.HinesJ.B.Hickman,NRC-Washington,D.C.AEP:NRC:1168ADC-N-6015.1-w/oattachments STATEOFOHIO)COUNTYOFFRANKLIN)E.E.Fitzpatrick,beingdulysworn,deposesandsaysthatheistheVicePresidentoflicenseeIndianaMichiganPowerCompany,thathehasreadtheforgoingRequestforDeletionofUnit2TurbineOverspeedProtectionTechnicalSpecificationandknowsthecontentsthereof;andthatsaidcontentsaretruetothebestofhisknowledgeandbelief.Subscribedandsworntobeforemethis~edayof19~.NOTARYPUBLIC-BlTAD.HlLL~NOTARYPUOMCSTA1EorOHIOAYCOMMISSIOIIEXPIRES~
Attachment1toAEP:NRC:1168A10CFR50.92ANALYSISFORCHANGESTODONALDC.COOKNUCLEARPLANTUNIT2TECHNICALSPECIFICATIONS
Attachment1toAEP:NRC:1168APage11.0SectionstobeChanedUnit2T/SIndex-pagesVandXII,Unit2T/S3/4.3.4-pages3/43-65and3/43-66,Unit2Bases3/4.3.4-pageB3/43-4.2.0ExtentofChaneThislicenseamendmentrequestproposestodeleteTechnicalSpecification(T/S)3/4.3.4forUnit2anditsassociatedbasessectionandindexlistings.3.0SecificChanesReuesteda.WeproposetodeletetheentryonpageVoftheT/SindexforT/S3/4.3.4,TurbineOverspeedProtection.b.WeproposetodeletetheentryonpageXIIoftheT/SindexforBasessection3/4.3.4,TurbineOverspeedProtection.C,WeproposetodeleteT/S3/4.3'onpages3/43-65and3/43-66initsentirety.Toeffectthis,thepageswouldberemoved.d.WeproposetodeletethesecondparagraphanditsheadingonpageB3/43-4inthebasessection,therebydeletingthebasesonturbineoverspeedprotection.4.0DiscussionSstemDescritionadSafetFunctioAccordingtothebasesforthisT/S,thespecificationis"...providedtoensurethattheturbineoverspeedprotectioninstrumentationandtheturbinespeedcontrolvalvesareOPERABLEandwillprotecttheturbinefromexcessiveoverspeed.Protectionfromturbineexcessiveoverspeedisrequiredsinceexcessiveoverspeedoftheturbinecouldgeneratepotentiallydamagingmissileswhichcouldimpactanddamagesafetyrelatedcomponents,equipment,orstructures."ThepresentUnit2turbineoverspeedprotectionT/Slists"SurveillanceRequirements"b,c,anddonpage3/43-66undertheheadingof"LimitingConditionforOperation".ThisclericalerrorwillbecorrectedwhenthisT/Sisdeleted.
Attachment1toAEP:NRC:1168APage2TheUnit2turbinewasthefirstturbinemanufacturedbyBrownBoveritooperateatanuclearpowerplantinNorthAmerica.TherearetwoindependentmechanicaloverspeedtripsontheUnit2turbine.ThesurveillancerequirementsoftheUnit2T/Spresentlyrequirethatallturbinecontrol,stop,andinterceptvalvesbetestedthroughatleastonecompletecycleatleastoncepersevendays.ValvetestingisagoodpracticewhichisfollowedatCookNuclearPlant.FortheBrownBoveriturbinethesevalvesarecontrolledbytheTurbomatsystem.Aturbineshutdowntest,wherethevalvesarestroked,isperformedpriortoturbineroll.Thenormalturbinevalvetestisthenperformeduptosevendayslater.inMode1withabout8%powerormore.AtthattimetherequirementsforrunningtheTurbomatin"auto"havebeensatisfied.WiththeTurbomatin"auto",theTurbomatwilladjusttheremainingvalvestomaintainunitloadasonevalveistested.TheT/Salsorequiresdirectobservationofthemovementofeachofthevalvesonceper31days.Ithasbeenplantpracticethatthisdirectobservationbedoneeverysevendays,alsomeetingthe31dayT/Srequirements.TheT/Salsorequiresa"channelcalibration",whichisinterpretedtomeananactualoverspeedtest,oftheturbineoverspeedprotectionsystematleastonceper18months.OverspeedtestswillbecontinuedatCookNuclearPlantconsistentwithoperatingexperienceatCookNuclearPlantandapplicableindustryexperience.AlsoincludedintheT/Sistherequirementthatatleastonevalveofeachtype(control,mainstop,reheatstop,andreheatintercept)shallbedisassembledandinspectedatleastonceevery40months.ValveinspectionswillbecontinuedatCookNuclearPlantconsistentwithoperatingexperienceatCookNuclearPlantandapplicableindustryexperience.JustificationWebelievethatthepresenceofaT/Sforturbinevalvetestingandmaintenanceisinappropriateandunnecessarilyrestrictiveforabalance-of-plantsystem.Itisexpectedthattheoverspeedprotectionwillremainavailableduringpoweroperation.ThisT/SchangeistoproviderelieffromtherigidityofthepresentUnit2T/S.ThisT/Schangerequestisproposedforthefollowingreasons:thisT/Sisnotincludedinthenewstandardizedtechnicalspecifications(STS)developedbythemethodicallyengineered,restructured,andimprovedtechnicalspecifications(MERITS)program;itwillincreasethesimilarityoftheT/Ssforthetwounits;ourtestingpracticeswillnotsignificantlychange;since1983ourtestingresultsdonotshowsignsofadverseconditions;andwewillbelesslikelytotripthereactorasaresultoftryingtomeettheschedularrequirementsofthisT/S.
Attachment1toAEP:NRC:1168APage3ThenewSTSdevelopedbytheMERITSprograminNUREG-1431doesnotincludeaT/Sforturbineoverspeedprotection.Ourmaintenanceoftheturbineoverspeedprotectionsystemwillpreventchallengestomissile-protectedequipment,TheomissionofanoverspeedprotectionT/SinNUREG-1431indicatesthataT/Sisnotneeded.ThisviewissupportedbyWCAP11618whichusestheNRC's"InterimPolicyStatementCriteria"toevaluatetheneedforaturbineoverspeedprotectionT/Sandconcludesthatitisnotneeded.AsimilarT/SdoesnotexistforUnit1.ThereasonforthisisthattheSTSofNUREG-0452werenotavailablewhenUnit1waslicensedbutwereadoptedforUnit2.AlthoughUnit1doesnothavea'urbineoverspeedprotectionT/S,thesurveillancesperformedontheUnit1turbinearesimilartothoseperformedontheUnit2turbine,asthisissimplygoodsurveillanceandtestpracticebasedonoperatingexperienceatCookNuclearPlantandapplicableindustryexperience.TheresultoftheproposedT/SchangeswillbetoreducetherigidityoftheschedularrequirementtoperformthesurveillanceforturbineoverspeedprotectiononUnit2sothatbothunitswillbetestedunderanadministrativeprogramoutsideofthetechnicalspecificationsandinaccordwithoperatingexperienceatCookNuclearPlantandapplicableindustryexperience.ThissimilarityinT/SsbetweenUnit1andUnit2benefitsthesafeoperationofbothunitsbecausetheincreasedconsistencybetweentheunitsminimizesthechanceofhumanerror.DespitethedeletionofthisT/S,thesurveillancetestswillnotsignificantlychangeontheUnit2turbine.TurbineoverspeedprotectionandsurveillancewillbemaintainedonUnit2,similartowhathasalwaysexisted.'nlytheT/Swillbedeleted.GoodsurveillanceandtestpracticesbasedonoperatingexperienceatCookNuclearPlantandapplicableindustryexperiencewillcontinuetobefollowedunderanadministrativeprogramoutsideofT/Ss.TheUnit2turbineisnowoperatinginitsninthoperatingcyclewithover90,000hoursofoperation.Turbineoverspeedprotectionsurveillanceresultshavebeenverygoodsinceunitstartupin1978.In1983,awearproblemwasfoundwiththeoverspeedplungers.Replacementplungerswereinstalled.Thenin1988,theseplungerswerereplacedwithpartshavingstellited(hardened)surfaces.Therehavebeennosubsequentproblems.DuringnormalpoweroperationtherequirementtoperformthisT/Ssurveillancehasthepotentialforbringingtheunitdownandthensubjectingtheplanttotransients.InperformingthisT/Ssurveillancetheplantcanencounterdifficultiesthatareunrelatedtothefunctionalityofthevalvesandoverspeedtripprotection.WebelievethatitissafertocontinuetooperateinMode1whilethesedifficultiesareworkedoutbothfromthepointofviewofapotentialreactortripandtheadditionalstressonplantpersonneltoperformtheworkina72-hourwindow.ShuttingdowntheunitbecauseofdifficultiesperformingthisT/Ssurveillance,inouropinion,isinappropriateandunnecessary.
Attachment1toAEP:NRC:1168APage4TherearetwoindependentmechanicaloverspeedtripsontheUnit2turbine.Eachtripdeviceoperatesthroughaseparatechanneltotripallofthecontrol,mainstop,reheatstop,andreheatinterceptvalvesasitssetpointisreached.Eachmajorsteamlineenteringtheturbinehastwoindependentvalvesinseries.Thusitcanbeseenthatthereisredundantoverspeedprotection.TheBrownBoverilowpressureturbinerotorsareassembledfromseparateforgingsthatareweldedtogether.Theyarenotassembledusingashrunk--ondiskdesign.TheBrownBoveriweldeddesignisconsideredtobelesssusceptibletoturbineburst.5.0NoSiificantHazardsDeterminatioWehaveevaluatedtheproposedT/Schangesandhavedeterminedthatthechangesshouldinvolvenosignificanthazardsconsiderationbasedonthecriteriaestablishedin10CFR50.92(c).OperationofCookNuclearPlantinaccordancewiththeproposedamendmentwillnotsatisfyanyofthefollowingcriteria.(a)Involveasinificantincreaseintherobabilitorconseuencesofanaccidentreviouslevaluated.Theproposedamendmentdoesnotinvolveasignificantincreaseintheprobabilityorconsequencesforanaccidentpreviouslyevaluated.TheproposeddeletionoftheturbineoverspeedprotectionT/SwillnotsignificantlychangethesurveillancetestsontheUnit2turbine.ThesurveillancescheduleandtestswillbeunderadministrativeproceduresoutsideoftheTSssimilartothatofUnit1andwillbeinlinewithoperatingexperienceatCookNuclearPlantandapplicableindustryexperience.TheUnit2turbineisnowoperatinginitsninthoperatingcyclewithover90,000hoursofoperation.Turbineoverspeedprotectionsurveillanceresultshavebeenverygoodsinceunitstartupin1978.In1983,awearproblemwasfoundwiththeoverspeedplungers.Replacementplungerswereinstalled.Thenin1988,theseplungerswerereplacedwithpartshavingstellited(hardened)surfaces.Therehavebeennosubsequentproblems.Ourexpectationisthattheturbineoverspeedprotectionsystemwillremainavailabletoperformitsfunctionofpreventingexcessiveturbineoverspeed.Lastly,theSTSdevelopedbytheMERITSprograminNUREG-1431donotincludeaT/Sforturbineoverspeedprotection.TheomissionofanoverspeedprotectionT/SinNUREG-1431indicatesthataT/Sisnotneededtoensureanadequatelevelofsafetyforanuclearfacility.ThisviewissupportedbyWCAP11618whichusestheNRC's"InterimPolicyStatementCriteria"toevaluatetheneedforaturbineoverspeedprotectionT/Sandconcludesthatitisnotneeded.Forthesereasons,webelievethatdeletingtheturbineoverspeedprotectionT/Swillnotsignificantlyincreasetheprobabilityorconsequencesofanaccidentpreviouslyevaluated.
Attachment1toAEP:NRC:1168APage5(b)Createtheossibilitofanewordifferentkindofaccidentfromanreviouslanalzed.Theproposedamendmentdoesnotcreatethepossibilityofanewordifferentkindofaccidentfromanypreviouslyevaluated.ThisrequesttodeletetheturbineoverspeedprotectionT/SeliminatesacontrolonthesurveillancetestingoftheUnit2turbine.Thedesignfunctionoftheturbineoverspeedprotectionandtheoperationoftheturbine/generatorremainthesame.TheoperatinghistoryoftheUnit2surveillanceresultstodateandourcontinuedtestingsupporttheviewthattheturbineoverspeedprotectionwillremainavailable.Forthesereasons,webelievethattheproposedchangeswillnotcreatethepossibilityofanewordifferentkindofaccidentfromanypreviouslyanalyzed.(c)InvoveasiificantreductioninamariofsafetTheproposedamendmentdoesnotinvolveasignificantreductioninthemarginofsafety.Turbineoverspeedprotectionsurveillanceresultshavebeenexcellentsince1983.TheyearsofoperatingdatawellwithinacceptancecriteriaonUnit2turbineoverspeedprotectionprovideampleevidencethatthereisnosignificantdegradationofthesystemtoperformitsfunction.Thereliabilityoftheoverspeedprotectionwasimprovedbythereplacementoftheplungerswithpartshavingstellitedsurfaces.ThesurveillancescheduleandtestswillbebasedonoperatingexperienceatCookNuclearPlantandapplicableindustryexperience.SurveillancetestingwillcontinueunderanadministrativeprogramoutsideofTSs.Thustheturbineoverspeedprotectionisexpectedtoremainavailable.AlsobyeliminatingthisT/SwewillbereducingthepotentialforshuttingdowntheunitbecauseofdifficultiesperformingthisT/Ssurveillanceunrelatedtothefunctionalityofthevalvesandoverspeedtripprotection.Lastly,theSTSdevelopedbytheMERITSprograminNUREG-1431donotincludeaT/Sforturbineoverspeedprotection.TheomissionofanoverspeedprotectionT/SinNUREG-1431indicatesthataT/Sisnotneededtoensureanadequatelevelofsafetyforanuclearfacility.ThisviewissupportedbyWCAP11618whichusestheNRC's"InterimPolicyStatementCriteria"toevaluatetheneedforaturbineoverspeedprotectionT/Sandconcludesthatitisnotneeded.Forthesereasons,webelievethattheturbineoverspeedprotectionsystemwillremainoperableandsothisproposedamendmentdoesnotinvolveasignificantreductioninthemarginofsafety.
Attachment1toAEP:NRC:1168APage66.0PendinTSProosalsImactinThisSubmittalNoneofthepagesinthissubmittalimpactnorareimpactedbyanycurrentlypendingT/Sproposals.
Attachment2toAEP:NRC:1168AEXISTINGTECHNICALSPECIFICATIONSPAGESMARKEDTOREFLECTPROPOSEDCHANGES