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| | issue date = 10/25/1996 | | | issue date = 10/25/1996 |
| | title = Informs That Util Agrees W/Nrc Staff Re Importance of Issues Surrounding Revised LBLOCA Evaluation Model.Final Analysis of Impact of Model Error on ECCS Acceptance Criteria Will Be Prepared | | | title = Informs That Util Agrees W/Nrc Staff Re Importance of Issues Surrounding Revised LBLOCA Evaluation Model.Final Analysis of Impact of Model Error on ECCS Acceptance Criteria Will Be Prepared |
| | author name = BOHLKE W H | | | author name = Bohlke W |
| | author affiliation = FLORIDA POWER & LIGHT CO. | | | author affiliation = FLORIDA POWER & LIGHT CO. |
| | addressee name = | | | addressee name = |
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| =Text= | | =Text= |
| {{#Wiki_filter:CATEGORY1REGULATINFORMATION DISTRIBUTION STEM(RIDS)ACCESS3;0$ | | {{#Wiki_filter:CATEGORY 1 REGULAT INFORMATION DISTRIBUTION STEM (RIDS) |
| .NBR:9611050179 DOC.DATE: | | ACCESS3;0$ . NBR:9611050179 DOC.DATE: 96/10/25 NOTARIZED: NO DOCKET FACIL:50-335 St. Lucie Plant, Unit 1, Florida Power 6 Light Co. 05000335 AUTH. NAME AUTHOR AFFILIATION BOHLKE,W.H. Florida Power a Light Co. |
| 96/10/25NOTARIZED: | | RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk) |
| NOFACIL:50-335 St.LuciePlant,Unit1,FloridaPower6LightCo.AUTH.NAMEAUTHORAFFILIATION BOHLKE,W.H.
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| FloridaPoweraLightCo.RECIP.NAME RECIPIENT AFFILIATION DocumentControlBranch(Document ControlDesk)DOCKET05000335
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| ==SUBJECT:== | | ==SUBJECT:== |
| Informsthatutilagreesw/NRCstaffreimportance ofissuessurrounding revisedLBLOCAevaluation model.FinalanalysisofimpactofmodelerroronECCSacceptance criteriawillbeprepared.
| | Informs that util agrees w/NRC staff re importance of issues surrounding revised LBLOCA evaluation model. Final analysis of impact of model error on ECCS acceptance criteria will be prepared. A DISTRIBUTION CODE: A001D COPIES RECEIVED:LTRK ENCL SIZE: |
| DISTRIBUTION CODE:A001DCOPIESRECEIVED:LTRK ENCLSIZE:TITLE:ORSubmittal: | | TITLE: OR Submittal: General Distribution E |
| GeneralDistribution NOTES:AERECIPIENT IDCODE/NAME PD2-3LAWIENSiL.COPIESRECIPIENT LTTRENCLIDCODE/NAME 11'D2-3PD11COPIESLTTRENCL110INTERNAL:
| | NOTES: |
| ACRSNRR/DE/EMCB NRR/DSSA/SPLB NUDOCS-ABSTRACT EXTERNAL:
| | RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID PD2-3 LA WIENSiL. |
| NOAC1111111111FILECENTERRR/DRCHHICBNRR/DSSA/SRXB OGC/HDS3NRCPDR1111111011DNOTETOALL"RIDS"RECIPIENTS:
| | 1 1 |
| PLEASEHELPUSTOREDUCEWASTE.TOHAVEYOURNAMEORORGANIZATION REMOVEDFROMDISTRIBUTION LISTSORREDUCETHENUMBEROFCOPIESRECEIVEDBYYOUORYOURORGANIZATION, CONTACTTHEDOCUMENTCONTROLDESK(DCD)ONEXTENSION 415-2083TOTALNUMBEROFCOPIESREQUIRED:
| | 1 1 |
| LTTR13ENCL12 FloridaPower&LightCompany,P.O.Box14000,JunoBeach,FL33408-0420 OgT251996L-96-28310CFR50.46U.S.NuclearRegulatory Commission Attn:DocumentControlDeskWashington, D.C.20555Re:St.LucieUnit1DocketNo.50-335RevisedLBLOCAEvaluation Model;Prelimina Assessment ofImactonPCTRef:(1)NRCletter:BrianW.SherontoT.F.Plunkett, 10CFR50.46LARGEBREAKLOSS-OF-COOLANTACCIDENTEVALUATION MODELFORST.LUCIEPLANT,UNIT1(TACNO.M96355);October11,1996.(2)Telecon10/24/96, 4:00pm,J.A.Zwolinski(NRC),
| | 'D2-3 CODE/NAME PD LTTR ENCL 1 1 0 |
| etal,toW.H.Bohlke(FPL),et.al.Reference (1)informedFloridaPowerandLightCompany(FPL)ofproblemsidentified bytheNRCconcerning changestotheSiemensPowerCorporation (SPC)largebreakloss-of-coolant (LBLOCA)evaluation modelusedbySPCforpressurized waterreactors.
| | INTERNAL: ACRS 1 1 FILE CENTER 1 1 NRR/DE/EMCB 1 1 RR/DRCH HICB 1 1 NRR/DSSA/SPLB 1 1 NRR/DSSA/SRXB 1 1 NUDOCS-ABSTRACT 1 1 OGC/HDS3 1 0 EXTERNAL: NOAC 1 1 NRC PDR 1 1 D |
| Theletterrequested thatFPLevaluate, inaccordance with10CFR50.46(a)(3)(ii),
| | NOTE TO ALL "RIDS" RECIPIENTS: |
| theimpactofidentified modelerrorsandchanges,andtakewhateveractionsarerequiredtoassurecompliance with10CFR50.46.FPLagreeswiththeNRCstaffregarding theimportance oftheissuessurrounding thesubjectLBLOCAevaluation model.Asdiscussed inReference (2),FPLhasagreedtodocumentthecurrentassessment andtherationale leadingtoFPL'sconclusion thatSt.LucieUnit1isoperating incompliance with10CFR50.46.Theattachment tothislettercontainsthatassessment withsupporting rationale.
| | PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD) ON EXTENSION 415-2083 TOTAL NUMBER OF COPIES REQUIRED: LTTR 13 ENCL 12 |
| Becausethecurrentassessment's calculational resultshavenotreceivedfinalverification bySPC,FPLisalsopreparing afinalanalysisoftheimpactoftheLBLOCAmodelerroronemergency corecoolingsystemacceptance criteria.
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| FPLwillsubmitthisanalysistotheNRCuponcompletion ofitsreviewofSPCrevisedcalculational modelfinalresults.Pleasecontactusifthereareanyquestions regarding thissubmittal.
| | Florida Power & Light Company, P.O. Box 14000, Juno Beach, FL 33408-0420 OgT 2 5 1996 L-96-283 10 CFR 50.46 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Re: St. Lucie Unit 1 Docket No. 50-335 Revised LBLOCA Evaluation Model; Prelimina Assessment of Im act on PCT Ref: (1) NRC letter: Brian W. Sheron to T.F. Plunkett, 10 CFR 50.46 LARGE BREAK LOSS-OF-COOLANT ACCIDENT EVALUATIONMODEL FOR ST. LUCIE PLANT, UNIT 1 (TAC NO. |
| Verytrulyyours,W.H.BohlkeVicePresident NuclearEngineering WHB/RLD~~nnCid96ii050i79 qhi025PDRADQCK05000335PPDR
| | M96355); October 11, 1996. |
| | (2) Telecon 10/24/96, 4:00 pm, J.A. Zwolinski(NRC), et al, to W.H. Bohlke (FPL), et.al. |
| | Reference (1) informed Florida Power and Light Company (FPL) of problems identified by the NRC concerning changes to the Siemens Power Corporation (SPC) large break loss-of-coolant (LBLOCA) evaluation model used by SPC for pressurized water reactors. The letter requested that FPL evaluate, in accordance with 10 CFR 50.46(a)(3)(ii), the impact of identified model errors and changes, and take whatever actions are required to assure compliance with 10 CFR 50.46. |
| | FPL agrees with the NRC staff regarding the importance of the issues surrounding the subject LBLOCAevaluation model. As discussed in Reference (2), FPL has agreed to document the current assessment and the rationale leading to FPL's conclusion that St. Lucie Unit 1 is operating in compliance with 10 CFR 50.46. The attachment to this letter contains that assessment with supporting rationale. |
| | Because the current assessment's calculational results have not received final verification by SPC, FPL is also preparing a final analysis of the impact of the LBLOCAmodel error on emergency core cooling system acceptance criteria. FPL will submit this analysis to the NRC upon completion of its review of SPC revised calculational model final results. |
| | Please contact us if there are any questions regarding this submittal. |
| | Very truly yours, W. H. Bohlke Vice President Nuclear Engineering |
| | ~ ~ nnCid WHB/RLD 96ii050i79 qhi025 05000335 PDR P |
| | ADQCK |
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| ==Attachment:== | | ==Attachment:== |
| | LBLOCA Assessment For St. Lucie Unit PDR 1 |
| | QG( i cc: Stewart D. Ebneter, Regional Administrator, Region II, USNRC. |
| | Senior Resident Inspector, USNRC, St. Lucie Plant. |
| | an FPL Group company |
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| | ATTACHMENT LBLOCA Assessment For St. Lucle Unit 1 FPL has performed an assessment for St. Lucie Unit 1 in light of NRC's concern with the calculation of peak cladding temperature (PCT) resulting from a Large Break Loss of Coolant Accident (Reference 1). The NRC identified non-physical behavior in the heat transfer coefficient for reflood rates between 1.00 in/sec and 1.77 in/sec in the NRC approved 1986 ECCS/LBLOCA evaluation model for Siemens Power Corporation (SPC). FPL has developed a modification to the heat transfer coefficient with a linear function between 1.00 in/sec and 1.77 in/sec which corrects the non-physical behavior of the reflood heat transfer correlation. FPL concludes that this modification is appropriate because: |
| | i) The end points for interpolating the heat transfer coefficient are the respective values at flooding rates of 1.00 in/sec and 1.77 in/sec. |
| | ii) The linear interpolation of the heat transfer coefficient between the flooding rates of 1.00 in/sec and 1.77 in/sec follows the trend of increasing heat transfer coefficient with increasing reflood rate shown by the FLECHT test data (Reference 2). |
| | iii) The values of the heat transfer coefficient throughout the range of interest are conservative for pressurized water reactor applications. |
| | An assessment of PCT using the above interpolation approach has shown a PCT of 2027 F (Reference 3), which is an increase of 115 F with respect to the current analysis of record PCT of 1912 F. The recalculated PCT remains well below the 10 CFR 50.46 criterion of 2200 F (margin ) 150 F). |
| | However, the magnitude of the increase meets the definition of significant change per 10 CFR 50.46. |
| | In addition, the preliminary results of the calculation show that the maximum local cladding oxidation is much less than 17% and the core wide maximum oxidation is much less than 1%. In conclusion, the 10 CFR 50.46 acceptance criteria remain satisfied. |
| | The information used by FPL to reach its conclusion is based upon computer code calculations which have not received a formal verification under SPC's and FPL's quality assurance programs. A formal review of this analysis is currently in progress. |
| | Meanwhile, FPL has performed a review of the above analytical results with respect to the following major parameters. The review concludes that the operation of St. Lucie Unit 1 will continue to remain in compliance with 10 CFR 50.46: |
| | Heat Transfer Coefficient: The heat transfer coefficient in the current analysis is less than that seen with the uncorrected 1986 model correlation. The behavior of the heat transfer coefficient with time at various elevations is as expected. |
| | Flooding Rate: The flooding rate shows a drop from a value of -2 in/sec at 75 seconds to a value of -1.2 in/sec at 150 seconds into the transient. The calculated increase in PCT is consistent with the reduced heat transfer coefficient in this range of flooding rates. |
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| LBLOCAAssessment ForSt.LucieUnit1QG(icc:StewartD.Ebneter,RegionalAdministrator, RegionII,USNRC.SeniorResidentInspector, USNRC,St.LuciePlant.anFPLGroupcompany 0I;'<<)'r ATTACHMENT LBLOCAAssessment ForSt.LucleUnit1FPLhasperformed anassessment forSt.LucieUnit1inlightofNRC'sconcernwiththecalculation ofpeakcladdingtemperature (PCT)resulting fromaLargeBreakLossofCoolantAccident(Reference 1).TheNRCidentified non-physical behaviorintheheattransfercoefficient forrefloodratesbetween1.00in/secand1.77in/secintheNRCapproved1986ECCS/LBLOCA evaluation modelforSiemensPowerCorporation (SPC).FPLhasdeveloped amodification totheheattransfercoefficient withalinearfunctionbetween1.00in/secand1.77in/secwhichcorrectsthenon-physical behavioroftherefloodheattransfercorrelation.
| | l 1-Peak Cladding Temperature: The PCT has increased and the corresponding time to reach the PCT has increased by more than 30 seconds under the reduced heat transfer coefficient assumption. This behavior of PCT following modification of the heat transfer coefficient is as expected and the magnitude of the change appears reasonable. |
| FPLconcludes thatthismodification isappropriate because:i)Theendpointsforinterpolating theheattransfercoefficient aretherespective valuesatfloodingratesof1.00in/secand1.77in/sec.ii)Thelinearinterpolation oftheheattransfercoefficient betweenthefloodingratesof1.00in/secand1.77in/secfollowsthetrendofincreasing heattransfercoefficient withincreasing refloodrateshownbytheFLECHTtestdata(Reference 2).iii)Thevaluesoftheheattransfercoefficient throughout therangeofinterestareconservative forpressurized waterreactorapplications.
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| Anassessment ofPCTusingtheaboveinterpolation approachhasshownaPCTof2027F(Reference 3),whichisanincreaseof115FwithrespecttothecurrentanalysisofrecordPCTof1912F.Therecalculated PCTremainswellbelowthe10CFR50.46criterion of2200F(margin)150F).However,themagnitude oftheincreasemeetsthedefinition ofsignificant changeper10CFR50.46.Inaddition, thepreliminary resultsofthecalculation showthatthemaximumlocalcladdingoxidation ismuchlessthan17%andthecorewidemaximumoxidation ismuchlessthan1%.Inconclusion, the10CFR50.46acceptance criteriaremainsatisfied.
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| Theinformation usedbyFPLtoreachitsconclusion isbaseduponcomputercodecalculations whichhavenotreceivedaformalverification underSPC'sandFPL'squalityassurance programs.
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| Aformalreviewofthisanalysisiscurrently inprogress.
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| Meanwhile, FPLhasperformed areviewoftheaboveanalytical resultswithrespecttothefollowing majorparameters.
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| Thereviewconcludes thattheoperation ofSt.LucieUnit1willcontinuetoremainincompliance with10CFR50.46:HeatTransferCoefficient:
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| Theheattransfercoefficient inthecurrentanalysisislessthanthatseenwiththeuncorrected 1986modelcorrelation.
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| Thebehavioroftheheattransfercoefficient withtimeatvariouselevations isasexpected.
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| FloodingRate:Thefloodingrateshowsadropfromavalueof-2in/secat75secondstoavalueof-1.2in/secat150secondsintothetransient.
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| Thecalculated increaseinPCTisconsistent withthereducedheattransfercoefficient inthisrangeoffloodingrates.
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| l1-PeakCladdingTemperature:
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| ThePCThasincreased andthecorresponding timetoreachthePCThasincreased bymorethan30secondsunderthereducedheattransfercoefficient assumption.
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| ThisbehaviorofPCTfollowing modification oftheheattransfercoefficient isasexpectedandthemagnitude ofthechangeappearsreasonable.
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| ==References:== | | ==References:== |
| | : 1. Letter B. W. Sheron (NRR) 'to T. F. Plunkett (FPL),"10 CFR 50.46 Large Break Loss-Of-Coolant Accident Evaluation Model For St. Lucie Unit 1 (TAC No. M96355)," dated October 11, 1996. |
| | : 2. N. Lee, "PWR FLECHT SEASET Unblocked Bundle, Forced and Gravity Reflood Task, Data Evaluation and Analysis Report," EPRI-NP-2013 NUREG/CR-2256 WCAP-9891 February 1982. |
| | : 3. Letter TMH:96:223, T. M. Howe (SPC) to R. J. Rodriguez (FPL), "Assessment of Non-Physical Behavior in Heat Transfer for St. Lucie Unit 1 LBLOCA," October 23,1996. |
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| 1.LetterB.W.Sheron(NRR)'toT.F.Plunkett(FPL),"10 CFR50.46LargeBreakLoss-Of-CoolantAccidentEvaluation ModelForSt.LucieUnit1(TACNo.M96355)," | | c A 1+}} |
| datedOctober11,1996.2.N.Lee,"PWRFLECHTSEASETUnblocked Bundle,ForcedandGravityRefloodTask,DataEvaluation andAnalysisReport,"EPRI-NP-2013 NUREG/CR-2256 WCAP-9891 February1982.3.LetterTMH:96:223, T.M.Howe(SPC)toR.J.Rodriguez (FPL),"Assessment ofNon-PhysicalBehaviorinHeatTransferforSt.LucieUnit1LBLOCA,"October23,1996.
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Category:CORRESPONDENCE-LETTERS
MONTHYEARML17241A5001999-10-21021 October 1999 Forwards Rev 3 to Emergency Response Data Sys (ERDS) Data Point Library for St Lucie Unit 1.Rev Provides Replacement Pages & Follows Format Recommended by NUREG 1394, ERDS Implementation, Rev 1,App C ML17309A9981999-10-19019 October 1999 Forwards Revised Epips,Including Rev 3 to EPIP-10 & Rev 25 to HP-202.EPIP-10 Added Onsite Monitoring Points,Made Administrative Changes & Incorporated New Attachments & HP-202 Added Red Team Survey Points ML20217F6171999-10-0808 October 1999 Forwards Insp Repts 50-335/99-11 & 50-389/99-11 on 990827 & 990907-09.No Violations Identified.Matl Encl Contained Safeguards Info as Defined by 10CFR73.21 & Disclosed to Unauthorized Individuals Prohibited by Section 147 of AEA ML17241A4811999-10-0101 October 1999 Reports Number of Tubes Plugged During Unit 1 Refueling Outage SL1-16,per TS 4.4.5.5.a ML20212M1601999-09-28028 September 1999 Refers to 990908 Engineering Meeting Conducted at NRC Region II to Discuss Engineering Issues at Lucie & Turkey Point Facilities.List of Attendees & Copy of Presentation Handout Encl ML17241A4701999-09-25025 September 1999 Forwards Info Requested by NRC Staff During 990916 Telcon to Complete Staff Review of Request for risk-informed Extension of Action Completion/Aot Specified for Inoperable Train of LPSI Sys at Plant ML17241A4721999-09-24024 September 1999 Forwards Rev 1 to Plant Change/Mod (PCM) 99016 to St Lucie Unit 1,Cycle 16 COLR, IAW TS 6.9.1.11.d.Refueling Overhaul Activities Are Currently in Progress & Reactor Operations for Cycle 16 Are Scheduled to Commence in Oct 1999 ML17241A4681999-09-22022 September 1999 Requests Restriction Be Added to Senior Operator License SOP-21093 for TE Bolander.Nrc Forms 369,encl.Encl Withheld Per 10CFR2.790(a)(6) ML17241A4671999-09-20020 September 1999 Forwards Completed NRC Form 536, Operator Licensing Exam Data, for St Lucie Units 1 & 2,as Requested in Administrative Ltr 99-03, Preparation & Scheduling of Operator Licensing Exams. ML17241A4581999-09-13013 September 1999 Forwards Info Requested by NRC Staff During 990630 & 0816 Telcons,To Complete Review of Proposed License Amend for Fuel Reload Process Improvement Program ML17241A4531999-08-31031 August 1999 Informs That No Candidates from St Lucie Plant Will Be Participating in PWR Gfes Being Administered on 991006 ML17241A4521999-08-31031 August 1999 Withdraws Relief Request 16 & Suppl Relief Request 15 with Info Requested During 990526 Telephone Conference Re ISI Insp Plan,Third 10-yr Interval ML17241A4501999-08-26026 August 1999 Informs That FPL Has Reviewed Reactor Vessel Integrity Database,Called RVID2,re Closure of GL 92-01,rev 1,suppl 1. Requested Corrections & Marked Up Pages from Rvid 2 Database Summary Repts That Correspond to Comments,Attached ML17241A4371999-08-13013 August 1999 Forwards fitness-for-duty Program Performance Data for six- Month Period Ending 990630,per 10CFR26.71(d) ML17241A4461999-08-11011 August 1999 Requests That W Rept Entitled, Evaluation of Turbine Missile Ejection Probability Resulting from Extending Test Interval of Interceptor & Reheat Stop Valves at St Lucie Units 1 & 2, Be Withheld from Public Disclosure L-99-171, Forwards Rev 56 to Physical Security Plan.Summary of Changes & Marked Up Copy of Revised Pages Also Encl.Encls Withheld from Public Disclosure Per 10CFR2.790(a)(3)1999-07-29029 July 1999 Forwards Rev 56 to Physical Security Plan.Summary of Changes & Marked Up Copy of Revised Pages Also Encl.Encls Withheld from Public Disclosure Per 10CFR2.790(a)(3) ML17309A9911999-07-26026 July 1999 Forwards Revised EPIPs & Revised Procedures That Implement Emergency Plan as Listed.Procedures Provides Instruction for Operational Support Ctr (OSC) Chemistry Supervisor to Establish Remote Labs at Locations Specified ML17241A4471999-07-22022 July 1999 Requests That Rev 1 to WCAP-14732 & Rev 1,Add 1 to WCAP-14732 Be Withheld from Public Disclosure ML17241A4221999-07-22022 July 1999 Forwards List of Proposed Licensing Actions for St Lucie Units 1 & 2,planned During Fys 2000 & 2001,in Response to Administrative Ltr 99-02, Operating Reactor Licensing Action Estimates. ML17241A4151999-07-22022 July 1999 Forwards Revised Relief Request 25 for Second 10-yr ISI Interval for Unit 2 ML17241A4101999-07-16016 July 1999 Forwards FP&L Supplemental Response to NRC Request for Info Re Y2K Readiness at Nuclear Power Plants ML17309A9881999-07-0707 July 1999 Forwards Rev 5 to EPIP-03, Emergency Response Organization Notification/Staff Augmentation. Rev 5 to EPIP-03 Was Revised to Transfer EP Responsibilities from Training Manager to Protection Svcs Manager ML20209F1541999-07-0606 July 1999 Informs That NRC in Process of Conducting Operational Safeguards Response Evaluations at Nuclear Power Reactors. Plant Chosen for Such Review Scheduled for Wk of 990823-26 ML17241A4011999-06-30030 June 1999 Forwards Info Copy of Florida Wastewater Permit (FL0002208) (Formerly NPDES Permit) Mod,Which Was Issued by Florida Dept of Environ Protection on 990604 ML17241A3971999-06-30030 June 1999 Forwards Suppl Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Movs, as Requested in 990317 Ltr ML17355A3661999-06-30030 June 1999 Forwards Florida Power & Light Topical QA Rept, Dtd June 1999.Encl I Includes Summary of Changes Made to Topical QA Rept Since 1998 ML17241A3951999-06-29029 June 1999 Provides Response to NRC Request for Info Re Y2K Readiness at Nuclear Power Plants.Gl 98-01, Y2K Readiness of Computer Sys at Nuclear Power Plants, Requested Response on Status of Facility Y2K Readiness by 990701.Disclosure Encl ML17241A3731999-06-17017 June 1999 Supplements Relief Requests 4,11 & 13 for Third ten-year ISI Interval with Info Requested During 990526 Telcon.Expedited Review Is Requested by 990730 to Avoid Negatively Impacting Upcoming St Lucie Unit 1 Refueling Outage (SL1-16) ML17241A3641999-06-14014 June 1999 Submits Supplement to Relief Request 24 with Info Requested by Nrc.In Addition Relief Request 24 Is Identical to St Lucie Unit 1 Relief Request 4 for Third ISI Interval Being Supplemented by FPL Ltr L-99-139 ML20195F3871999-06-11011 June 1999 Final Response to FOIA Request for Documents.App a Records Being Withheld in Entirety (Ref FOIA Exemption 5) IA-99-247, Final Response to FOIA Request for Documents.App a Records Being Withheld in Entirety (Ref FOIA Exemption 5)1999-06-11011 June 1999 Final Response to FOIA Request for Documents.App a Records Being Withheld in Entirety (Ref FOIA Exemption 5) L-99-129, Forwards Rev 55 to Physical Security Plan,Summary of Changes & Marked Up Copy of Revised Pages.With Directions for Incorporating Rev Into Plan & Copies of Replacement Pages.Rev Withheld,Per 10CFR2.790(a)(3)1999-06-0909 June 1999 Forwards Rev 55 to Physical Security Plan,Summary of Changes & Marked Up Copy of Revised Pages.With Directions for Incorporating Rev Into Plan & Copies of Replacement Pages.Rev Withheld,Per 10CFR2.790(a)(3) ML17241A3561999-06-0707 June 1999 Forwards Rept Containing Brief Description & Summary of SEs for Changes,Tests & Experiments Which Were Approved for Unit 3 During Period of 970526-981209 ML17241A3601999-06-0707 June 1999 Forwards Correction to Annual Radiological Environ Operating Rept for CY98.Util Has Identified Transcription Error on Last Page of Attachment C of Rept,Results from Interlaboratory Comparison Program 1998 ML20195F3941999-05-27027 May 1999 FOIA Request That Memo from J Calvo to Fl Lebdon Re TIA - St Lucie,Unit 1 Environ Qualification of Woodward Governor Controls Be Placed in PDR ML17241A3461999-05-24024 May 1999 Forwards Revised Relief Request 22 to Clarify Several Areas of Relief.Nrc Action Is Requested to Be Complete by Aug 1999 to Support Planning for Spring 2000 Unit 2 Refueling Outage ML17241A3391999-05-20020 May 1999 Forwards Notification of Change to Small Break LOCA ECCS Evaluation Model Used for St Lucie Unit 1.Anomaly Was Discovered & Corrected That Resulted in Reducing Calculated PCT for Limiting SBLOCA by More than 50 F ML17241A3371999-05-20020 May 1999 Forwards Util Suppl to GL 95-07 Response Re pressure-locking & Thermal Binding of safety-related power-operated Gate Valves,In Response to NRC Second RAI Dtd 990225 ML20207C7531999-05-17017 May 1999 Discusses Issue Identified by FPL in Feb 1998 Involving Potential for Fire to Cause Breach of Rc Sys High/Low Pressure Interface Boundary & NRC Decision for Exercise of Enforcement Discretion ML17241A3301999-05-17017 May 1999 Forwards LER 99-004-00 Re as Found Cycle 10 Psv Setpoints Outside TS Limits,Which Occurred on 990415.Root Cause Determination Not Yet Complete.Suppl to Include Root Cause & Corrective Actions Will Be Submitted ML17309A9821999-05-10010 May 1999 Forwards Rev 36 to St Lucie Emergency Plan, Per 10CFR50.54(q).Executive Summary & Summary of Changes Incorporated by Rev,Encl IR 05000335/19980141999-04-29029 April 1999 Provides Confirmation of NRC Staff Conclusions Re Cited & non-cited Violations in Insp Rept 50-335/98-14 & 50-389/98-14.Utils Position Re Consideration of Multiple Spurious Actuations in Event of Fire,Reiterated ML17241A3221999-04-29029 April 1999 Provides Confirmation of NRC Staff Conclusions Re Cited & non-cited Violations in Insp Rept 50-335/98-14 & 50-389/98-14.Utils Position Re Consideration of Multiple Spurious Actuations in Event of Fire,Reiterated ML17229B1071999-04-28028 April 1999 Forwards 1998 Annual Environ Operating Rept for St Lucie Unit 2. Rept Includes Discussions of 5-inch Barrier Net Maint & Taprogge Condenser Tube Cleaning Sys Ball Loss,As Agreed at First Biennial Sea Turtle Meeting Held on 980120 ML17229B1051999-04-22022 April 1999 Requests That Listed Individuals Be Placed on Official Serve List for Nuclear Matl Safety & Safeguards Info Notices ML17229B1061999-04-21021 April 1999 Notifies NRC of Change in Medical Status of Licensed Operator Pf Farnsworth (Docket 55-21285,license SOP-21094). NRC Form 3996, Medical Exam Certification, Encl.Encl Withheld Per 10CFR2.790(a)(6) ML17309A9851999-04-15015 April 1999 Requests That NRC Review Denial of Appeal from Assessment of Fees Assessed in 981101 Invoice RS0062-99 & Assessment of Fees in Invoice RS0182-99 Which Was Also Denied in 990305 Ltr.Both Invoices Are for Fees Re Inspector GG Warnick ML20205M0431999-04-13013 April 1999 Eighth Partial Response to FOIA Request for Records.App Q & R Records Encl & Being Made Available in PDR ML17229B0951999-04-0808 April 1999 Requests Approval of Encl Revised Relief Request 6,in Response to 990322 Telcon with NRC & 10CFR55.55a(a)(3). Request States That Visual VT-3 Exams Will Be Conducted IAW IWA-2213 & Repairs Will Be IAW Util ASME Section IX Program ML17229B0821999-04-0707 April 1999 Requests Approval of Interim Relief Request 26 Re Repair Requirements for Class 2 ECCS Piping,Per 10CFR50.55a(a)(3) & 50.55a(g)(iii).Alternative Actions Apply Guidance of GLs 91-18 & 90-05 & ASME Code Case N-513.Evaluation,encl 1999-09-28
[Table view] Category:INCOMING CORRESPONDENCE
MONTHYEARML17241A5001999-10-21021 October 1999 Forwards Rev 3 to Emergency Response Data Sys (ERDS) Data Point Library for St Lucie Unit 1.Rev Provides Replacement Pages & Follows Format Recommended by NUREG 1394, ERDS Implementation, Rev 1,App C ML17309A9981999-10-19019 October 1999 Forwards Revised Epips,Including Rev 3 to EPIP-10 & Rev 25 to HP-202.EPIP-10 Added Onsite Monitoring Points,Made Administrative Changes & Incorporated New Attachments & HP-202 Added Red Team Survey Points ML17241A4811999-10-0101 October 1999 Reports Number of Tubes Plugged During Unit 1 Refueling Outage SL1-16,per TS 4.4.5.5.a ML17241A4701999-09-25025 September 1999 Forwards Info Requested by NRC Staff During 990916 Telcon to Complete Staff Review of Request for risk-informed Extension of Action Completion/Aot Specified for Inoperable Train of LPSI Sys at Plant ML17241A4721999-09-24024 September 1999 Forwards Rev 1 to Plant Change/Mod (PCM) 99016 to St Lucie Unit 1,Cycle 16 COLR, IAW TS 6.9.1.11.d.Refueling Overhaul Activities Are Currently in Progress & Reactor Operations for Cycle 16 Are Scheduled to Commence in Oct 1999 ML17241A4681999-09-22022 September 1999 Requests Restriction Be Added to Senior Operator License SOP-21093 for TE Bolander.Nrc Forms 369,encl.Encl Withheld Per 10CFR2.790(a)(6) ML17241A4671999-09-20020 September 1999 Forwards Completed NRC Form 536, Operator Licensing Exam Data, for St Lucie Units 1 & 2,as Requested in Administrative Ltr 99-03, Preparation & Scheduling of Operator Licensing Exams. ML17241A4581999-09-13013 September 1999 Forwards Info Requested by NRC Staff During 990630 & 0816 Telcons,To Complete Review of Proposed License Amend for Fuel Reload Process Improvement Program ML17241A4531999-08-31031 August 1999 Informs That No Candidates from St Lucie Plant Will Be Participating in PWR Gfes Being Administered on 991006 ML17241A4521999-08-31031 August 1999 Withdraws Relief Request 16 & Suppl Relief Request 15 with Info Requested During 990526 Telephone Conference Re ISI Insp Plan,Third 10-yr Interval ML17241A4501999-08-26026 August 1999 Informs That FPL Has Reviewed Reactor Vessel Integrity Database,Called RVID2,re Closure of GL 92-01,rev 1,suppl 1. Requested Corrections & Marked Up Pages from Rvid 2 Database Summary Repts That Correspond to Comments,Attached ML17241A4371999-08-13013 August 1999 Forwards fitness-for-duty Program Performance Data for six- Month Period Ending 990630,per 10CFR26.71(d) ML17241A4461999-08-11011 August 1999 Requests That W Rept Entitled, Evaluation of Turbine Missile Ejection Probability Resulting from Extending Test Interval of Interceptor & Reheat Stop Valves at St Lucie Units 1 & 2, Be Withheld from Public Disclosure L-99-171, Forwards Rev 56 to Physical Security Plan.Summary of Changes & Marked Up Copy of Revised Pages Also Encl.Encls Withheld from Public Disclosure Per 10CFR2.790(a)(3)1999-07-29029 July 1999 Forwards Rev 56 to Physical Security Plan.Summary of Changes & Marked Up Copy of Revised Pages Also Encl.Encls Withheld from Public Disclosure Per 10CFR2.790(a)(3) ML17309A9911999-07-26026 July 1999 Forwards Revised EPIPs & Revised Procedures That Implement Emergency Plan as Listed.Procedures Provides Instruction for Operational Support Ctr (OSC) Chemistry Supervisor to Establish Remote Labs at Locations Specified ML17241A4221999-07-22022 July 1999 Forwards List of Proposed Licensing Actions for St Lucie Units 1 & 2,planned During Fys 2000 & 2001,in Response to Administrative Ltr 99-02, Operating Reactor Licensing Action Estimates. ML17241A4471999-07-22022 July 1999 Requests That Rev 1 to WCAP-14732 & Rev 1,Add 1 to WCAP-14732 Be Withheld from Public Disclosure ML17241A4151999-07-22022 July 1999 Forwards Revised Relief Request 25 for Second 10-yr ISI Interval for Unit 2 ML17241A4101999-07-16016 July 1999 Forwards FP&L Supplemental Response to NRC Request for Info Re Y2K Readiness at Nuclear Power Plants ML17309A9881999-07-0707 July 1999 Forwards Rev 5 to EPIP-03, Emergency Response Organization Notification/Staff Augmentation. Rev 5 to EPIP-03 Was Revised to Transfer EP Responsibilities from Training Manager to Protection Svcs Manager ML17241A4011999-06-30030 June 1999 Forwards Info Copy of Florida Wastewater Permit (FL0002208) (Formerly NPDES Permit) Mod,Which Was Issued by Florida Dept of Environ Protection on 990604 ML17241A3971999-06-30030 June 1999 Forwards Suppl Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Movs, as Requested in 990317 Ltr ML17355A3661999-06-30030 June 1999 Forwards Florida Power & Light Topical QA Rept, Dtd June 1999.Encl I Includes Summary of Changes Made to Topical QA Rept Since 1998 ML17241A3951999-06-29029 June 1999 Provides Response to NRC Request for Info Re Y2K Readiness at Nuclear Power Plants.Gl 98-01, Y2K Readiness of Computer Sys at Nuclear Power Plants, Requested Response on Status of Facility Y2K Readiness by 990701.Disclosure Encl ML17241A3731999-06-17017 June 1999 Supplements Relief Requests 4,11 & 13 for Third ten-year ISI Interval with Info Requested During 990526 Telcon.Expedited Review Is Requested by 990730 to Avoid Negatively Impacting Upcoming St Lucie Unit 1 Refueling Outage (SL1-16) ML17241A3641999-06-14014 June 1999 Submits Supplement to Relief Request 24 with Info Requested by Nrc.In Addition Relief Request 24 Is Identical to St Lucie Unit 1 Relief Request 4 for Third ISI Interval Being Supplemented by FPL Ltr L-99-139 L-99-129, Forwards Rev 55 to Physical Security Plan,Summary of Changes & Marked Up Copy of Revised Pages.With Directions for Incorporating Rev Into Plan & Copies of Replacement Pages.Rev Withheld,Per 10CFR2.790(a)(3)1999-06-0909 June 1999 Forwards Rev 55 to Physical Security Plan,Summary of Changes & Marked Up Copy of Revised Pages.With Directions for Incorporating Rev Into Plan & Copies of Replacement Pages.Rev Withheld,Per 10CFR2.790(a)(3) ML17241A3601999-06-0707 June 1999 Forwards Correction to Annual Radiological Environ Operating Rept for CY98.Util Has Identified Transcription Error on Last Page of Attachment C of Rept,Results from Interlaboratory Comparison Program 1998 ML17241A3561999-06-0707 June 1999 Forwards Rept Containing Brief Description & Summary of SEs for Changes,Tests & Experiments Which Were Approved for Unit 3 During Period of 970526-981209 ML20195F3941999-05-27027 May 1999 FOIA Request That Memo from J Calvo to Fl Lebdon Re TIA - St Lucie,Unit 1 Environ Qualification of Woodward Governor Controls Be Placed in PDR ML17241A3461999-05-24024 May 1999 Forwards Revised Relief Request 22 to Clarify Several Areas of Relief.Nrc Action Is Requested to Be Complete by Aug 1999 to Support Planning for Spring 2000 Unit 2 Refueling Outage ML17241A3371999-05-20020 May 1999 Forwards Util Suppl to GL 95-07 Response Re pressure-locking & Thermal Binding of safety-related power-operated Gate Valves,In Response to NRC Second RAI Dtd 990225 ML17241A3391999-05-20020 May 1999 Forwards Notification of Change to Small Break LOCA ECCS Evaluation Model Used for St Lucie Unit 1.Anomaly Was Discovered & Corrected That Resulted in Reducing Calculated PCT for Limiting SBLOCA by More than 50 F ML17241A3301999-05-17017 May 1999 Forwards LER 99-004-00 Re as Found Cycle 10 Psv Setpoints Outside TS Limits,Which Occurred on 990415.Root Cause Determination Not Yet Complete.Suppl to Include Root Cause & Corrective Actions Will Be Submitted ML17309A9821999-05-10010 May 1999 Forwards Rev 36 to St Lucie Emergency Plan, Per 10CFR50.54(q).Executive Summary & Summary of Changes Incorporated by Rev,Encl ML17241A3221999-04-29029 April 1999 Provides Confirmation of NRC Staff Conclusions Re Cited & non-cited Violations in Insp Rept 50-335/98-14 & 50-389/98-14.Utils Position Re Consideration of Multiple Spurious Actuations in Event of Fire,Reiterated IR 05000335/19980141999-04-29029 April 1999 Provides Confirmation of NRC Staff Conclusions Re Cited & non-cited Violations in Insp Rept 50-335/98-14 & 50-389/98-14.Utils Position Re Consideration of Multiple Spurious Actuations in Event of Fire,Reiterated ML17229B1071999-04-28028 April 1999 Forwards 1998 Annual Environ Operating Rept for St Lucie Unit 2. Rept Includes Discussions of 5-inch Barrier Net Maint & Taprogge Condenser Tube Cleaning Sys Ball Loss,As Agreed at First Biennial Sea Turtle Meeting Held on 980120 ML17229B1051999-04-22022 April 1999 Requests That Listed Individuals Be Placed on Official Serve List for Nuclear Matl Safety & Safeguards Info Notices ML17229B1061999-04-21021 April 1999 Notifies NRC of Change in Medical Status of Licensed Operator Pf Farnsworth (Docket 55-21285,license SOP-21094). NRC Form 3996, Medical Exam Certification, Encl.Encl Withheld Per 10CFR2.790(a)(6) ML17309A9851999-04-15015 April 1999 Requests That NRC Review Denial of Appeal from Assessment of Fees Assessed in 981101 Invoice RS0062-99 & Assessment of Fees in Invoice RS0182-99 Which Was Also Denied in 990305 Ltr.Both Invoices Are for Fees Re Inspector GG Warnick ML17229B0951999-04-0808 April 1999 Requests Approval of Encl Revised Relief Request 6,in Response to 990322 Telcon with NRC & 10CFR55.55a(a)(3). Request States That Visual VT-3 Exams Will Be Conducted IAW IWA-2213 & Repairs Will Be IAW Util ASME Section IX Program ML17229B0821999-04-0707 April 1999 Requests Approval of Interim Relief Request 26 Re Repair Requirements for Class 2 ECCS Piping,Per 10CFR50.55a(a)(3) & 50.55a(g)(iii).Alternative Actions Apply Guidance of GLs 91-18 & 90-05 & ASME Code Case N-513.Evaluation,encl ML17229B0851999-04-0505 April 1999 Requests Approval of Encl Relief Request 25 Which Proposes to Use Alternative Requirements of ASME Code Case N-613 in Lieu of Requirements of ASME Section XI Figures IWB-2500-7(a) & IWB-2500-7(b).Action Requested by Aug 1999 ML17309A9791999-03-31031 March 1999 Forwards Revised EPIPs Including Rev 2 to EPIP-00,rev 2 to EPIP-09,rev 2 to EPIP-10 & Rev 10 to HP-207.Summary of Revs Listed ML17309A9761999-03-23023 March 1999 Forwards Revised Epips,Including Rev 4 to EPIP-03, Er Organization Notification/Staff Augmentation, Rev 3 to EPIP-05, Activation & Operation of OSC & Rev 14 to HP-200, HP Emergency Organization. Changes to Epips,Discussed ML17229B0691999-03-19019 March 1999 Transmits TS Pages Requested by NRC for Use in Issuance of Proposed License Amend Re SFP Storage Capacity,Per Soluble Boron Credit ML17229B0721999-03-16016 March 1999 Requests Approval of Enclosed Relief Requests 23 & 24 Re ISI Plan for Second ten-year Interval.Nrc Action Is Requested to Be Complete by Aug 1999 to Support Planning for Spring 2000 Unit 2 Refueling Outage ML17355A2631999-03-12012 March 1999 Forwards FPL Decommissioning Fund Status Repts for St Lucie, Units 1 & 2 & Turkey Point,Units 3 & 4.Rept for St Lucie, Unit 2 Provides Status of Decommissioning Funds for All Three Owners of That Unit ML17229B0481999-03-10010 March 1999 Informs That Util Delivered Matls Requested in Encl 1 of NRC Ltr by Hand on 990308,as Requested by NRC Ltr Dtd 990218 1999-09-25
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CATEGORY 1 REGULAT INFORMATION DISTRIBUTION STEM (RIDS)
ACCESS3;0$ . NBR:9611050179 DOC.DATE: 96/10/25 NOTARIZED: NO DOCKET FACIL:50-335 St. Lucie Plant, Unit 1, Florida Power 6 Light Co. 05000335 AUTH. NAME AUTHOR AFFILIATION BOHLKE,W.H. Florida Power a Light Co.
RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Informs that util agrees w/NRC staff re importance of issues surrounding revised LBLOCA evaluation model. Final analysis of impact of model error on ECCS acceptance criteria will be prepared. A DISTRIBUTION CODE: A001D COPIES RECEIVED:LTRK ENCL SIZE:
TITLE: OR Submittal: General Distribution E
NOTES:
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INTERNAL: ACRS 1 1 FILE CENTER 1 1 NRR/DE/EMCB 1 1 RR/DRCH HICB 1 1 NRR/DSSA/SPLB 1 1 NRR/DSSA/SRXB 1 1 NUDOCS-ABSTRACT 1 1 OGC/HDS3 1 0 EXTERNAL: NOAC 1 1 NRC PDR 1 1 D
NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD) ON EXTENSION 415-2083 TOTAL NUMBER OF COPIES REQUIRED: LTTR 13 ENCL 12
Florida Power & Light Company, P.O. Box 14000, Juno Beach, FL 33408-0420 OgT 2 5 1996 L-96-283 10 CFR 50.46 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Re: St. Lucie Unit 1 Docket No. 50-335 Revised LBLOCA Evaluation Model; Prelimina Assessment of Im act on PCT Ref: (1) NRC letter: Brian W. Sheron to T.F. Plunkett, 10 CFR 50.46 LARGE BREAK LOSS-OF-COOLANT ACCIDENT EVALUATIONMODEL FOR ST. LUCIE PLANT, UNIT 1 (TAC NO.
M96355); October 11, 1996.
(2) Telecon 10/24/96, 4:00 pm, J.A. Zwolinski(NRC), et al, to W.H. Bohlke (FPL), et.al.
Reference (1) informed Florida Power and Light Company (FPL) of problems identified by the NRC concerning changes to the Siemens Power Corporation (SPC) large break loss-of-coolant (LBLOCA) evaluation model used by SPC for pressurized water reactors. The letter requested that FPL evaluate, in accordance with 10 CFR 50.46(a)(3)(ii), the impact of identified model errors and changes, and take whatever actions are required to assure compliance with 10 CFR 50.46.
FPL agrees with the NRC staff regarding the importance of the issues surrounding the subject LBLOCAevaluation model. As discussed in Reference (2), FPL has agreed to document the current assessment and the rationale leading to FPL's conclusion that St. Lucie Unit 1 is operating in compliance with 10 CFR 50.46. The attachment to this letter contains that assessment with supporting rationale.
Because the current assessment's calculational results have not received final verification by SPC, FPL is also preparing a final analysis of the impact of the LBLOCAmodel error on emergency core cooling system acceptance criteria. FPL will submit this analysis to the NRC upon completion of its review of SPC revised calculational model final results.
Please contact us if there are any questions regarding this submittal.
Very truly yours, W. H. Bohlke Vice President Nuclear Engineering
~ ~ nnCid WHB/RLD 96ii050i79 qhi025 05000335 PDR P
ADQCK
Attachment:
LBLOCA Assessment For St. Lucie Unit PDR 1
QG( i cc: Stewart D. Ebneter, Regional Administrator, Region II, USNRC.
Senior Resident Inspector, USNRC, St. Lucie Plant.
an FPL Group company
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ATTACHMENT LBLOCA Assessment For St. Lucle Unit 1 FPL has performed an assessment for St. Lucie Unit 1 in light of NRC's concern with the calculation of peak cladding temperature (PCT) resulting from a Large Break Loss of Coolant Accident (Reference 1). The NRC identified non-physical behavior in the heat transfer coefficient for reflood rates between 1.00 in/sec and 1.77 in/sec in the NRC approved 1986 ECCS/LBLOCA evaluation model for Siemens Power Corporation (SPC). FPL has developed a modification to the heat transfer coefficient with a linear function between 1.00 in/sec and 1.77 in/sec which corrects the non-physical behavior of the reflood heat transfer correlation. FPL concludes that this modification is appropriate because:
i) The end points for interpolating the heat transfer coefficient are the respective values at flooding rates of 1.00 in/sec and 1.77 in/sec.
ii) The linear interpolation of the heat transfer coefficient between the flooding rates of 1.00 in/sec and 1.77 in/sec follows the trend of increasing heat transfer coefficient with increasing reflood rate shown by the FLECHT test data (Reference 2).
iii) The values of the heat transfer coefficient throughout the range of interest are conservative for pressurized water reactor applications.
An assessment of PCT using the above interpolation approach has shown a PCT of 2027 F (Reference 3), which is an increase of 115 F with respect to the current analysis of record PCT of 1912 F. The recalculated PCT remains well below the 10 CFR 50.46 criterion of 2200 F (margin ) 150 F).
However, the magnitude of the increase meets the definition of significant change per 10 CFR 50.46.
In addition, the preliminary results of the calculation show that the maximum local cladding oxidation is much less than 17% and the core wide maximum oxidation is much less than 1%. In conclusion, the 10 CFR 50.46 acceptance criteria remain satisfied.
The information used by FPL to reach its conclusion is based upon computer code calculations which have not received a formal verification under SPC's and FPL's quality assurance programs. A formal review of this analysis is currently in progress.
Meanwhile, FPL has performed a review of the above analytical results with respect to the following major parameters. The review concludes that the operation of St. Lucie Unit 1 will continue to remain in compliance with 10 CFR 50.46:
Heat Transfer Coefficient: The heat transfer coefficient in the current analysis is less than that seen with the uncorrected 1986 model correlation. The behavior of the heat transfer coefficient with time at various elevations is as expected.
Flooding Rate: The flooding rate shows a drop from a value of -2 in/sec at 75 seconds to a value of -1.2 in/sec at 150 seconds into the transient. The calculated increase in PCT is consistent with the reduced heat transfer coefficient in this range of flooding rates.
l 1-Peak Cladding Temperature: The PCT has increased and the corresponding time to reach the PCT has increased by more than 30 seconds under the reduced heat transfer coefficient assumption. This behavior of PCT following modification of the heat transfer coefficient is as expected and the magnitude of the change appears reasonable.
References:
- 1. Letter B. W. Sheron (NRR) 'to T. F. Plunkett (FPL),"10 CFR 50.46 Large Break Loss-Of-Coolant Accident Evaluation Model For St. Lucie Unit 1 (TAC No. M96355)," dated October 11, 1996.
- 2. N. Lee, "PWR FLECHT SEASET Unblocked Bundle, Forced and Gravity Reflood Task, Data Evaluation and Analysis Report," EPRI-NP-2013 NUREG/CR-2256 WCAP-9891 February 1982.
- 3. Letter TMH:96:223, T. M. Howe (SPC) to R. J. Rodriguez (FPL), "Assessment of Non-Physical Behavior in Heat Transfer for St. Lucie Unit 1 LBLOCA," October 23,1996.
c A 1+