ML17333A901

Forwards Response to 970326 RAI Re Plant Raceway/Fire Stop Configuration in Response to Concerns for GL-92-08, Thermo-Lag 330-1 Fire Barriers.

ML17333A901
Person / Time
Site:	Cook
Issue date:	05/21/1997
From:	FITZPATRICK E AMERICAN ELECTRIC POWER CO., INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML17333A902	List: ML17333A901 ML17333A905 ML17333A906 ML17334B630 ML17334B631
References
AEP:NRC:0692DM, AEP:NRC:692DM, GL-92-08, GL-92-8, TAC-M85538, TAC-M85539, NUDOCS 9705290178
Download: ML17333A901 (12)

Text

CATEGORY1REGULATOYINFORMATION DISTRIBUTION YSTEM(RIDS)ACCESSION NBR:9705290178 DOC.DATE:97/05/21NOTARIZED:NODOCKETFACIL:50-315DonaldC.CookNuclearPoeerPlantiUnitiiIndianaM0500031550'-316DonaldC.CookNucleav.PoeerPlant.Unit2.EndianaM05000316AUTH.NAI'IEAUTHORAFFILIATION FITZPATRICKiE.AmericanElectricPowerCo.~Inc.RECIP.NAME,RECIPIENT AFFILIATION DocumentControlBranch(Document ControlDesk)

SUBJECT:

Forfardsresponseto.970326RAIreplantraceway/f irestopconfiguration inresponsetoconcernsfovGL-92-08.

"Thermo-Lag 330-1FireBav;vievs."DISTRIBUTION CODE:A029DCOPEESRECEI')ED:

LTRENCLSIZE:IITLE:GenevicLettev92-008Thermo-Lag 330FireBavrievNOTES:+87ERECIPEENTIDCODE/NAI'IE PD3-3LAHECKMANiJINTERNAL.

FILECEN~TZ~O~'%FR/DRPW/PD3-1 RGN3FILF.11111NRR/DE/EELB NRR/DSS*/SPL'B COPIESRECIPIENT LTTRENCLIDCODE/NAME 0PD3-3PD1COPIESLTTREiNCL11111,1G0YEXTERNAL:

NOACQI~R,~(ngS NRCPDR1oca,etwe~t'~iehD0NNOTETOALL"RZDS"RECIPZENTSI PLEASEHELPUSTOREDUCEWASTE.TOHAVEYOURNAMEORORGANIZATION REMOVEDFROMDISTRIBUTION LISTSORREDUCETHENUMBEROFCOPIESRECEIVEDBYYOUORYOURORGANIZATION, CONTACTTHEDOCUMENTCONTROLDESK(DCD)ONEXTENSION 415-2083TOTALNUMBEROFCOPEESREQUIRED:

LTTR10ENCL9ed-8 tall IndianaMichigan~PowerCompany500CircleDriveBuchanan, Mi491071395 INQMNASllml6ANPQWMMay21,1997AEP:NRC:0692DM DocketNos.:50-31550-316U.S.NuclearRegulatory Commission ATTN:DocumentControlDeskWashington, D.C.20555Gentlemen:

DonaldC.CookNuclearPlantUnits1and2RESPONSETOGENERICLETTER92-08(TACNOS.M85538ANDM85539)THERMO-LAG 330-1FIREBARRIERSREQUESTFORADDITIONAL INFORMATION InourletterdatedDecember27,1996(AEP:NRC:692DB),

weinformedtheNRCthatcorrective actionsinresponsetotheconcernsidentified inNRCgenericletter92-08,andsubsequent requestsforadditional information, havebeencompleted atCookNuclearPlant.ByletterdatedMarch26,1997,yourstaffrequested additional information concerning howourraceway/fire stopconfiguration, described inAEP:NRC:692DB, meetstheNRCfireprotection requirements andCookNuclearPlantlicensing anddesignbases.Ourresponsetotherequestforadditional information iscontained intheattachments.

Attachment 1describes ouruseoffirestopsforthe20footseparation boundary.

Attachments 2and3containthetechnical evaluations forauxiliary buildingfirezones6Mand6S,andfirezones44Nand44S,respectively.

Attachments 4and5containdesigndetaildrawings2-1434R-5 and2-1419R-6, respectively.

Sincerely, CWpE.E.Fitzpatrick VicePresident vlbAttachments CC:A.A.BlindA.B.BeachMDEQ-DWEcRDPNRCResidentInspector J.R.Padgett9705290i78 PDR"ADOCKP97052i050003i5PDR3%&.gIN(.e~0Lzsff!ffff!fff!ffllllfffffffffrfffffffff 1lE ATTACHMENT 1TOAEP:NRC:0692DM FIRESTOPSFOR20FOOTSEPARATION BOUNDARY

Attachment 1toAEP:NRC:0692DM Page1IntheNRCRAIdatedMarch26,1997,thefollowing requestwasmade."Additional information isrequiredtoresolvethestaff'squestions andreviewthenewconfiguration.

Specifically, pleaseaddress,indetail,howtheraceway/fire stopconfiguration described intheletterofDecember27,1996,meetsNRCfireprotection requirements andtheD.C.Cooklicensing anddesignbases.Inthisdiscussion, identifyanyexemptions fromSectionIII.GorAppendixRto10CFRPart50thathavebeenrequested andgrantedforthefirestopconfigurations described intheletterofDecember27,1996.Inaddition, submitthedesigndetailsofthefirestops,thedrawingsshowingthelocations oft.hefirestopsandfireareaswheretheyarecredited, andtheengineering analysesthatsupportachieving a20footseparation usingcabletrayfire"-tops."NRCFireProtection Reuirements andCookNuclearPlantLicensinandDesinBasesThesafeshutdowncapability assessment (SSCA)wascreatedtoaddresscompliance with10CFR50,appendixR,sectionZIZ.G.AppendixR,sectionZIZ.G.2.(b) providesonemeansofensuringthatoneoftheredundant trainsisfreeoffiredamage.Thissectionstates,"[S]eparation ofcablesandequipment andassociated non-safetycircuitsofredundant trainsbyahorizontal distanceofmorethan20feetwithnointervening combustible orfirehazards.Inaddition, firedetectors andanautomatic firesuppression systemshallbeinstalled inthefirearea;...."

Rev.0oftheSSCA,datedMarch1983,wassubmitted totheNRConMarch31,1983,byourletterAEP:NRC:0692E.

Thissubmittal contained sections8.3.1and8.16.1,thatdescribed twolocations wheresectionZII.G.2.(b) wasutilized.

Inbothituations, theSSCAstatedthatcertain"opencabletraystraversing thezonefromthenorthsidetothesouthsidewillbeappropriately firestoppedtopreventfirepropagation fromonesectionofthefirezonetotheother"Rev.1totheSSCAwassubmitted onMarch20,1987,byAEP:NRC:~92AZ.Therewasnochangetothestatements insections8.3.1and8.16.1quotedabove.Genericletter(GL)86-10containsguidanceregarding themeaningandintentofsectionIII.G.2.(b) wordingforintervening combustibles andexemption requests.

Basedontheinformation inGL86-10,thecablesinthetrayswithoutsomeformofnon-combustible coveringareconsidered intervening combustibles.

However,becausetheuseoffirestopsmetouroriginallicensing bases(SSCA)andpredatedGL86-10,wedidnotbelievetheinstallation ofadditional firestopswarranted anexemption requestrelativetothesubjectfirestopconfiguration.

DesinDetailsAttachments 4and5aredrawingsthatshowthetwolocations wherefirestopsareprovidedinaccordance withsectionIII.G.2.(b)

.Thesedrawingsshowthecabletrayslocatedinthesubject20footseparation spaces,thelocationofthefirestopsonthetrays,detailsofthefirestops,andfirezonelocations.

Thesedrawingshavedetailsshowingextensions addedtothesidesofcertaintrays.Thefollowing isprovidedtoclarifywhyandhowtheseextensions wereadded.Forsomecontrolcableinstallations, additional spacewasneededforproperinstallation ofthesilicone Attachment 1toAEP:NRC:0692DM Page2foamandspreading ofthecables.Theaddedspaceisprovidedbysheetmetalextensions.

Inattachment 4,theseextensions are'hownondrawing2-1419R-6 indetailsKB,MB,F9,H9,K9andM9,andinattachment 5ondrawing2-1434R-S, theyareshownindetailsJ2andL2.Fortheseinstallations, thesidesoftheraceway/fire stopconfigurations havebeenextendedasshown.Thisdesigndetailisnotapplicable topowercabletrays.Thesiliconefoamisentirelyenclosedbetweenthemetalhousingandthedammingmaterial.

Thedammingmaterialattheendsofthesiliconefoamreservoir separates thecontrolcables.Asthesiliconefoamexpandsandfillstheenclosedspace,italsoseparates thecontrolcables.EnineerinAnalsesThatSuortAchievina20FootSearationUsinCableTraFireStosAttachments 2and3aretechnical evaluations 11.42and1.43respectively.

Attheendofeachofthetechnical evaluations thereisaconclusion section.Thatsectionprovidesasummaryofthedefense-in-depth thatleadstotheconclusion thatafireoneithersideofthesubject20footseparation spaceswillnotspreadtotheotherside.Thissummarydoesnottakecreditforotherattributes suchastheenclosed(controlcable)traysandthesmallquantityofcables,rangingfrom3to20,intheopen(powercable)trays,bothofwhichfurthercontribute tominimizing theimpactoftheintervening combustibles withinthedesignated 20footspaces.Duringpreparation ofthisresponse, itwasnoticedthatthetitleandpurposeofthesetechnical evaluations mayneedclarification.

AppendixRsectionIII.G.2.(b) wasparaphrased andcontainsthephrase"withnointervening combustibles".

Weagreethatthecablesunderdiscussion areintervening combustibles.

However,thesetechnical evaluation evaluatetheabilityofthe"twentyfootwideseparation space"topreventthespreadoffirebetweenfirezonesandtomaintainsafeshutdowncapability forbothunits.Threedifferences betweenthecurrentdesign/procedures andthedescription inthetechnical evaluations werenoted.Allthreedifferences haveeithernoimpactortheyenhancethea~~cribed situation.

Thethreedifferences are:1)theboundaries haveshiftedslightlyfromthosedescribed intheevaluations andshownonthesketchesattachedtotheevaluations (noimpact);2)thefireloadingshavebeenreducedbecauseofthermo-lag removal(enhancement);

and3)thedailytourisbeingupgradedtoaprocedure versusaguideline (enhancement).

Thesedifferences havenosignificant impactontheevaluations.

~SummarTheSSCA(rev.0and1),submitted totheNRC,statedthatacommitment tomeetappendixR,sectionIII.G.2.(b) requirements attwolocations wouldbeaccomplished byproviding firestopsincabletraystraversing theseparation space.Nocommitment wasmadetoprovideacoveringoftheintervening combustibles.

Thethermo-lag wasbelievedtobeanon-combustible wrappingandwasaddedtosomecabletraystraversing theseparation space.Whenthethermo-lag wasremoved,thecablebetweenthefirestopsbecameanintervening combustible.

Becauseourlicensing basesuseoffirestopspredatedGL86-10guidance, webelievedthatanexemption wasnotrequired.

Thesafeshutdownimpactoftheuseoffirestopsiscontained inthetechnical evaluations preparedfor

Attachment 1toAEP:NRC:0692DM Page3theselocat'ons.

Thesetechnical ovaluations showthattheintentofappendixR,section'ZXE.G.2.(b) hasbeenmet.

J ATTACHMENT 2TOAEP:NRC:0692DM TECHNICAL EVALUATION FORAUXILIARY BUILDINGFIREZONES6MAND6S