ML082840372

Three-Month Supplemental Response to NRC Generic Letter 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal and Containment Spray Systems

ML082840372
Person / Time
Site:	Calvert Cliffs
Issue date:	10/10/2008
From:	Spina J A Calvert Cliffs, Constellation Energy Group, Nuclear Generation Group
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
GL-08-001
Download: ML082840372 (4)

Text

James A.Spina Calvert CliffsNuclear P owerPlant,In c.V ice President 1650Calvert C liffsParkwa y Lusby , Maryland 20657 410.495.5200 4 10.4 95.3500 Fa x'-'U'**,stellationEn y uclear eneration Group October 10 , 2008U.S.Nuclear Regulatory Com mission Washington,DC20555 ATTEN T ION: SU B JECT:

REFERENCES:

Document Control Desk Ca lvert Cli ffs Nuclear Power Plant UnitNos.1and2;Docke tNos.50-317 and 50-318 Three-MonthSupp lemental Response t o NRC Generic Letter2008-01

,"ManagingGas Accumulation in Emergency Core Cool ing , Decay Heat Removal.and Containment Spray Systcms" (a)NRC Generic Letter2008-01

, dated January II, 2008 ,"Managing Gas Accumu lation in Emergency Core Cooling , Decay Heat Removal,and Containment Spray Systems" (b)LetterfromMr.J.A

.Spina (CCNPP)toDoc ument Co ntrol Desk (NRC), datedAprilII , 2008 , Three-Month ResponsetoNRC Generic Letter 2008-01 ,"Managing Gas Accumulation in Emergency Core Cooling , Decay Heat Removal , and Containment Spray Systems" (c)LetterfromMr.J.A.Spina (CCNPP)to Documen t Contro l Desk (NRC), date d Jun e 25, 2008, C hange to Thre e-MonthRes ponse t o NRC Generic Letter 2008-01,"Ma nagingGasA ccum u lation in Emergency Core Cooling, Decay Heat Removal, a nd Contai nment Spray Systems" (d)LetterfromMr.M.G.Kowal (NRC)toMr.J.A.Spina (CCNPP), dated August4,2008, Calvert Cliffs Nuclear Power Plant Unit2Re: Generic Letter 2008-01,"Managing Gas Accumu latio n in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems ," Propos ed Alternative Course o f Action (TAC No.MD7808)Reference (a)requested each licensee to provide certain informationina written response ,tobe submitted in accordancewith10 CFR 50.54(f), within nine mont hs ofthedate of the Generic Letter(G L).Additiona lly, Reference (a)requested that ifali censee cannot meet th e requested responsedate,the licensee"shall provide a response within 3 month s of th edateo f this GL." Inthe three-month response, the licensee was requestedtodes cribe the alternative c ourse of actionthati t proposestotake, includingtheba sisforthea cceptability o f the proposed alternative c ourse of action.I n Reference(b),as revised in Referen ce (c),we provided our three-month responsetoth e information requested in NuclearRegulatory Comm i ssion (NRC)GL200 8-01forU nit 2, includingadescription o f DocumentControlDesk October10,2008Page2ourproposed alternative course ofaction.In Reference(d),theNRC stafffoundourproposed alternative course ofactionacceptable,withthe exception of the clarifications and associated requests delineated in the enclosuretoReference(d)

.The clarificationsweretobe submittedinathree-month supplemental response.Thisletterprovidesthe three-month supplementalresponserequestedperReference(d)

.Specifically, as requestedinReference(d),wearerevisingourproposed alternative course of action (Referencesbandc)relatedtoournine-monthinitialresponseasfollows:

I.TheGLrequested informationfortheportions of the subjectsystemsforUnit2thatare accessiblepriortothenext refuelingoutageforUnit2,willbe providedtotheNRCinournine-month initial submittal.

2.Exceptforthelong-term actions describedbelow,the remaining GL requested informationforthesubjectsystemsforUnit2(i.e., GL requested informationforthe inaccessible portions of thesubjectsystems)willbe providedtotheNRCinour nine-month supplemental (post-outage)submittalwithin90daysfollowing completion ofthespring2009 refueling outage.3.Inournine-month initial submittal,wewilladdresshowweplantotracklong-termactionsrelatedtoadversegas accumulationissues.Long-termactionsweplantotrackinclude

a.The Technical SpecificationsTaskForce travelerthatmaybe necessarytoreflectanimproved understanding achievedduringreview ofresponsestotheGL, b.Theindustry assessment to determineifpumptestingis necessary to determine the allowable limits ofingestedgasvolumeinpump suctionpiping,and c.Theindustry assessment to determine whether analysis developmentisneededtoassessgas transportinthe subjectsystempipingasafunction ofsystemflow

.4.Inour nine-month initial submittalandinournine-month supplemental (post-outage) submittal , we will, consistentwiththe information requestedintheGL,provide

a.A description oftheresults of evaluationsthatwereperformedinresponsetotheGL,b.A description of correctiveactionsthatwe determinedwerenecessary,andc.A statement regarding which correctiveactionswere completed, the schedule for completing the remaining correctiveactionsandthebasisforthat schedule.Inourthree-month response (Referenceb)weproposedtodefer walkdowns and examinations of sections ofpipingforthesubjectsystemslocatedintheUnit2 ContainmentandintheUnit227'West PenetrationRoomuntilthenextUnit2 refueling outage (Spring 2009).Subsequenttoourthree-monthresponse,weidentifiedsections ofpipingforthesubjectsystemsthatarelocatedintheUnit25'West PenetrationRoom,whichalsorequiredeferral of the necessary walkdowns and examinationsuntilthenext scheduledUnit2refuelingoutage.Althoughthese sections ofpipingarelocatedinthe5'West Penetration Room (overhead),itismorepracticaltoaccessthepipingfromthe27'WestPenetrationRoom,alockedhighradiationarea

.Our alternative course ofactionplannedfortheadditional pipmgidentifiedintheUnit25'West PenetrationRoomistodeferthe walkdowns and examinationsuntilthenext scheduledUnit2 refuelingoutage.Plansarecurrentlybeing formulated to completetheseactionsshouldan opportunity develop providingaccesspriortothenext scheduledUnit2 refueling outage.Thebasisfor acceptabilityremainsas describedinReference(b)relativetothe pipmg previouslyidentifiedintheUnit2 Containmentandinthe27'West Penetration Room.ThisbasismayalsobeappliedtotheadditionalpipingidentifiedintheUnit 25'West Penetration Room.

Document Control Desk October 10 , 2008 Page3 Also , we identified section s of pipingforthes ubject syste ms thatarelocate dinthe Unit1Auxi liary Building[horizonta l run s of t he Unit 1 safety injectio n discharge pipingand two horizontalruns of refueling wa ter tank (R WT)norma l suctio n piping].Thispipingwasi nadvertently omitted fromth e sco pe of theUnit 1 walkdowns conducted.The requiredeval uations for this additionalidentifiedpip i ng w ill notb e completeb y October 11,2008 (ninemonthsfro mtheda te o fGL2008-01).O ur alternative course o f ac t ion plan nedforthesu b jec t pipingidentifiedinUnitI isto d eferthe wa l kdownsandexaminationsuntilthe nextavai lable on-line maintenance opportunity(n o latert han Augus t 30, 2009)forthe safety injectionsystemdischargep iping and th e nextscheduledUn itIrefueling outage (Spring2010)fort heRW T no rmal suction piping.Th e basisfo r acceptabilityi s asfollows: For theUnitIsafetyinjection dischargepipinghorizonta l ru ns: Thed ischarge piping designedhighpoints (invertedloopsea ls)were inspectedandfound full.Also, pointsa longthis pipingthathad thepo tential forgas collectiondueto back leakage and stripping have been inspectedand foundfull.Basedonthis,itis reasonablethatsubtle hig h points alo ng horizonta lrunsofthesame pipinga realsofu ll.T he August30,2009completiondatewasestablishedtoe nsure the subject activityisplanned, sc hedule d an d imp lemented in accorda nce w ith stationprocedures, comme nsurate with the ri sk significa nce associated with completing this task.Fort he Unit I RWTnormalsuction pipinglocatedi n the 27'West PenetrationRoo m: T heRWT supply headersflow horizontallyordown vertically t o thecommonECCS/CSsuction headersatthe(-)6" elevation.Thereareno designed high pointsin these p iperuns.The portionso fthemissedpip in g int he West PenetrationRoom representsasmallportionoftheoverall piperuns.The balanceo fthesepiperunshavebee n inspectedandlocal(highpointsofhorizontal run s)high pointshave been foundful l.A lso, we have not observed iss ues with gas ingestion fromRW T suct ion pipi ng.Based onth e above, itis reasonablethatthe subject sections o f horizonta lrunsarealsofull.Duringpoweroperation,the27'West PenetrationRoom isa locked high radiationarea.Currently, UnitIdoesnothave a scheduled outage to conduct th e requiredwa lk downs within the nine month period requestedint he G L.Thenext scheduled outageisthespri ng 2 010 Unit 1 refue lingo utage.Th er efore,t he sections ofpiping intheUnit 127'WestPenetrationRoomi dentif ie dabovew ill be d eferredunti l thenext schedu led Un it1re fueling ou tage.Based up on theabove,webelieve t hat completing pe rformance o fthedetailed walkdowns a nd s u bsequent evaluatio ns o f those portions of pip ingatUnits1a nd 2 , outside the requestednine

-month period,isa n acceptable alternative co urse o f action.For Unit2,within90daysafterthee nd of t he nex t scheduled Uni t2refueling out age,wewillsubmit a written response informing t heNRCo f t he activitiesperformedconsistent withtheactio ns a nd information requested byGL2008-01.ForU nit1,within90days afterthee nd ofthenext scheduled Un it1refue ling outage ,wew ill sub mit a written response i nforming theNRC of theactivitiesp e rformed consistent withtheactions and informationrequestedbyGL2008-01.

Document Control Des k October10,2008 Page 4 Should yo uhaveq uestio ns regarding th is m atter , p lease contactMr.JayS.Gainesat(410)495-5219.ou rs, 4---.,.-S TATE OF MARYLAND T O WIT: COUNTY O F CALVERT I , James A.Spina, bei ng du ly sworn, state that IamV ice President, Calve rt Cliffs Nuclear PowerPlant, Inc.(CCNPP), and tha t Iamdu ly aut horized to execute andfilethis responseon beh alf o f CCNPP.T o thebest of my knowledgeandbelief, th e statements conta inedinthis docu ment are true an d correct.T o th e exten t that these sta te mentsareno t based on m y perso nal knowledge, t heyarebasedupon information providedbyotherCCNPPe m ployees and/or consultant s.Such i nfor mationhasbeen reviewedi n accordance with compa ny practice an d I be lieveittobe reliable.subsc ribe Zt nd swo rn before me,a Notary Publicinan d for theState o f Marylanda nd County of.51.atl Q , t his 10+1--dayo f Ov+ober, 2008.WITNESS my Handand Notarial Seal: Notary Publi atetJ-o/1MyComm ission Expires: MDF/ALS/bjdcc:D.V.Pickett, NRC S.J.Collins, N RC Resident Inspector, NRC S.Gray , DNR