ML17331A296

Suppls 920515 Ltr Re Status of Mod of Commitment Re Control Room Habitability,Per GDC 19.Damper No Longer Being Maintained Closed.Ts Changes & Supporting Analyses Associated W/Control Room Habitability Will Be Submitted

ML17331A296
Person / Time
Site:	Cook
Issue date:	04/26/1993
From:	FITZPATRICK E INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	MURLEY T E NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
AEP:NRC:0398Y, AEP:NRC:398Y, NUDOCS 9305030341
Download: ML17331A296 (5)

Text

ACCELERATEDDOCUMENTDISTRIBUTIONSYSTEMREGULATINFORMATIONDISTRIBUTIO1YSTEM(RIDE)ACCESSIONNBR'.9305030341DOC.DATE:93/04/26NOTARIZED:NODOCKETFACIL:5Q.-315DonaldC.CookNuclearPowerPlant,Unit1,IndianaM0500031550-316DonaldC.CookNuclearPowerPlant,Unit2,IndianaM05000316AUTH.NAMEAUTHORAFFILIATIONFITZPATRICK,E.IndianaMichiganPowerCo.(formerlyIndiana&MichiganEleRECIP.NAMERECIPIENTAFFILIATIONMURLEY,T.E.DocumentControlBranch(DocumentControlDesk)I

SUBJECT:

Suppls920515ltrrestatusofmodofcommitmentrecontrolroomhabitability,perGDC19.Damperneednolongerbemaintainedclosed.TSchangesssupportinganalysesassociatedw/controlroomhabitabilitywillbesubmitted.DISTRIBUTIONCODE:A003DCOPIESRECEIVED:LTRiENCL0SIZE:TITLE:OR/LicensingSubmittal:Suppl1toNUREG-0737(GenericLtr82-33)NOTES:DRECIPIENTIDCODE/NAMEPD3-1LADEANFWINTERNAL:NR/JVRHHFBllEXILE01EXTERNAL:NRCPDRCOPIESLTTRENCLRECIPIENTIDCODE/NAMEPD3-1PDOC/LFMBRES/DSIR/EIBNSICCOPIESLTTRENCLDDDNOTETOALL"RIDS"RECIPIENTSPLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOMPl-37(EXT.504-2065)TOELIMINATEYOURNAMEFROMDISTRIBUTIONLISTSFORDOCUMENTSYOUDON'TNEED!TOTALNUMBEROFCOPIESREQUIRED:LTTR10ENCL AmericanElectricP~ServiceCorporation~1RiversidePlazaColumbus,OH432154142231000SlNMICQNKI.MTQICIrWMAEP:NRC:0398YDonaldC.CookNuclearPlantUnits1and2DocketNos.50-315and50-316LicenseNos.DPR-58andDPR-74MODIFICATIONOFCOMMITMENTREGARDINGCONTROLROOMHABITABILITYU.S.NuclearRegulatoryCommissionDocumentControlDeskWashington,D.C.20555Attn:T.E.MurleyApril26,1993

DearDr.Murley:

InourletterAEP:NRC:0398W,datedMay15,1992,weprovidedtheNRCwithinformationonmeasureswehaveimplementedattheDonaldC.CookNuclearPlantinordertobringthecontrolroomventilationsystemsmoreincompliancewiththeNRC'sinterpretationofthedoselimitsof10CFR50AppendixAGeneralDesignCriteria(GDC)19.Thisletterprovidesanupdatedstatusregardingthosemeasures.InAEP:NRC:0398W,wecommittedtomaintainingthe(non-redundant)normalintakeisolationdamperinaclosedposition,andtolimitallowableairintakeratessuchthatthewholebodyandthyroiddoseswouldbewithintheStandardReviewPlancriteriaof5and30rem,respectively.(Thesemeasureswouldresultinacorrespondingskindoseofapproximately32rem,whichwaswithin7%ofthe30remStandardReviewPlanlimit.)Maintainingthenormalintakeisolationdamperclosedeliminatedtheneedtoaccountforthepossiblefailureofthisdamper,andthusreducedthecalculateddoseeAlthoughthecontrolzoomremainedhabitablefromanenvironmentalperspectivewiththenormalintakeisolationdamperclosed,thiswasnotadesirablelongtermsolutionsinceitdoeslimittheamountoffreshairthatentersthecontrolroomduringnormaloperations.InordertoreducethecalculateddosesandthereforedemonstratecompliancewiththeStandardReviewPlandosecriteriawithoutrelyingonmaintainingthenormalintakeisolationdamperclosed,weobtainedtheservicesofameteorologicalconsultingfirmtoprovideaplantspecificdeterminationoftheatmosphericdispersionterm(Chi/Q)thatisusedintheanalyticalmodel.TheplantspecificevaluationresiiltedinaninetyfifthpercentileChi/Qof~I<<t930503034i<930426PDRADOCK05000315PDR' "iEl,'I~

Dr.T.E.MurleyAEP:NRC:0398Y7.85E-4sec/m3,versusthepreviousvalueof2.41E-3sec/m3whichhadbeenderivedusingthegenericmethodologyreferencedintheStandardReviewPlan.SincecalculateddosesaredirectlyproportionaltoChi/Q,thenewlycalculateddosesareonlyonethirdoftheprevious.Theconsultant'sreportisavailableforauditattheAEPSCofficesinColumbus,OHandattheCookNuclearPlant.Thereductionindoseenablesustoaccommodateafailureofthenon-redundantnormalintakeisolationdampertoclosewhilestilldemonstratingcompliancewiththeStandardReviewPlandoselimitsdose,providedappropriatelimitsonairintakeareapplied.(InaccordancewiththeguidanceofSection6.4oftheStandardReviewPlan,thedamperisassumedtobeclosedmanuallytwohoursaftertheaccident.)Therefore,thisdamperneednolongerbemaintainedclosed.LimitswillbeappliedtoairintakeratessuchthattheStandardReviewPlandoselimitsforwholebody,thyroid,andskindosesaremet.Itisourintenttosubmitproposedtechnicalspecificationchanges(andthesupportinganalyses)associatedwithcontrolroomhabitability.Thiswillbethesubjectofseparatecorrespondence.Sincerely,ee~~qE.E.FitzatrickVicePresidentdrcc:A.A.Blind-BridgmanJ.R.PadgettG.CharnoffA.B.Davis-RegionIIINRCResidentInspector-BridgmanNFEMSectionChief

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