ML17331A681

Submits Interim Rept on Corrective Actions Taken in Response to IE Bulletin 80-11, Masonry Wall Design. Mods on 39 Walls Will Be Completed by 811001.Final Rept Will Be Forwarded by 811031

ML17331A681
Person / Time
Site:	Cook
Issue date:	03/20/1981
From:	HUNTER R S INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	KEPPLER J G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
AEP:NRC:0418B, AEP:NRC:418B, IEB-80-11, NUDOCS 8104030543
Download: ML17331A681 (4)

Text

INDIANALMICHIGANELECTRICCOMPANYP.O.BOX18BOWLINGGREENSTATIONNEWYORK,N.Y.10004March20,1981AEP:NRC:0418B DonaldC.CookNuclearPlantUnitNos.1and2DocketNos.50-315and50-316LicenseNos.DPR-58andDPR-74Mr.JamesG.Keppler,DirectorU.S.NuclearRegulatory Commission OfficeofInspection andEnforcement RegionIII799Roosevelt RoadGlenEllyn,Illinois60137ApR01198'IIMshlQCLtARREGNATOCgOhNISSON

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Reference:

1)NRCIEBulletin80-11datedMay8,19802)LetterAEP:NRC:0418 datedJuly10,19803)LetterAEP:NRC:0418A datedJanuary14,1981

DearMr.Keppler:

Thisletterisaninterimreportontheactivities beingcarriedoutattheDonaldC.CookNuclearPlanttoaddresstheconcernsofReference (1).InReferences (2)and(3)wereportedthestatusoftheevaluation whichwaspartially completed atthattime.Thisletterreportstheresultsofourplantsurveyandthestatusofthewallevaluations.

Asreportedearlier,onehundredandthirty(130)masonrywallsattheCookPlantfallunderthescopeofthebulletin.

Wehavecompleted theplantsurveyofalltheaccessible walls.Eighteen(18)wallswereinaccessible duringpoweroperation (ononefaceofthewall)andwillbesurveyedduringthecurrentUnit2refueling outage,andthenextrefueling outageforUnitl.Theresultsofourfieldwalkanddesignevaluation are:a)NumberofwallsrecentlydesignedwhichmeetReference (1)Criteria..

~~~~~~~~~~~~~~~~68104080QgUMAR25>98)

EIIIllk.a)f~l~i'("*Piaa'Idf~,u Mr.JamesG.KepplerAEP:NRC:0418Bb)Numberofwallsthatcanwithstand theseismicforces,andnopipebreakloadsexist...........82 c)Numberofwallsthatrequiremodifications forseismicforces,andnopipebreakloadsexist...........................................39 d)Numberofwallsthatdonotrequiremodification forseismicforcesandareunderevaluation forpipebreakloads.............3TOTAL130Themodification ofthe39wallsnotedabovewillcommenceshortlyandweexpecttocompletetheworkbyOctober1,1981.Someofthemodifi-cationscanbeperformed duringplantoperation butsomerequirearefueling outage.ByOctober1,bothunitswillhavebeenoutofserviceforrefueling outages.The39wallsrequiring modification arenotloadbearingwalls;theyareforradiation shielding andareaseparation purposes.

Sincethesewallsarebuiltforspecificlocalconditions andarenotpartofthestructural system,thefailureofanyofthesewallsintheunlikelyeventofadesignbasisearthquake doesnotaffecttheintegrity ofthebuilding.

Further,itisonlyunderthemostconservative assumptions thatcollapseofthesewallscouldpossiblydamagesafety-related equipment atthePlant.Forexample,wehaveassumedanaffectedareaequaltotheareaofthewall,withnocreditforanyintervening equipment orinherentresistance oftheequipment itselftowalldebris.Considering theexceedingly lowprobability ofoccurrence ofaDBE,andthatthenecessary modifications willsoonbeimplemented, continued plantoperation iswarranted untilthecompletion ofsuchmodifi-cations.Thefinalreportofthedescription ofthedesignmodifications andplantchangeswillbesubmitted byOctober31,1981.WedonotintendtosubmitanotherinterimreportbyMay1,1981aspreviously notedinreference (3)Verytrulyyours,cc:R.C.CallenG.CharnoffJohnE.Dolan-ColumbusR.W.Jurgensen D.V.Shaller-BridgmanNRCResidentInspector 8CookPlant.HunterVicePresident 4'I