ML12216A354

Crystal River Unit 3 - Response to Second Request for Additional Information to Support NRC PRA Licensing Branch (Apla) Technical Review of the CR-3 Extended Power Uprate LAR (TAC No. ME6527)

ML12216A354
Person / Time
Site:	Crystal River
Issue date:	07/31/2012
From:	Franke J A Progress Energy Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
3F0712-08, TAC ME6527
Download: ML12216A354 (6)

Text

Progress EnergyCrystal River Nuclear PlantDocket No. 50-302Operating License No. DPR-72July 3.1, 20123F0712-08U.S. Nuclear Regulatory CommissionAttn: Document Control DeskWashington, DC 20555-0001Subject: Crystal River Unit 3 -Response to Second Request for Additional Information toSupport NRC PRA Licensing Branch (APLA) Technical Review of the CR-3 ExtendedPower Uprate LAR (TAC No. ME6527)References: 1. CR-3 to NRC letter dated June 15, 2011, "Crystal River Unit 3 -LicenseAmendment Request #309, Revision 0, Extended Power Uprate" (ADAMSAccession No. ML 112070659)2. Email from S. Lingam (NRC) to D. Westcott (CR-3) dated May 8, 2012, "CrystalRiver, Unit 3 EPU LAR -Additional Draft RAI from APLA (PRA Related)(ME6527)"3. NRC to CR-3 letter dated July 5, 2012, "Crystal River Unit 3 Nuclear GeneratingPlant -Request for Additional Information for Extended Power Uprate LicenseAmendment Request (TAC No. ME6527)" (ADAMS Accession No. ML 12171 A347)Dear Sir:By letter dated June 15, 2011, Florida Power Corporation (FPC) requested a license amendment toincrease the rated thermal power level of Crystal River Unit 3 (CR-3) from 2609 megawatts (MWt) to3014 MWt (Reference 1). On May 8, 2012, via electronic mail, the NRC provided a draft request foradditional information (RAI) needed to support the Probabilistic Risk Assessment (PRA) LicensingBranch technical review of the CR-3 Extended Power Uprate (EPU) License Amendment Request (LAR)(Reference 2). By teleconference on May 14, 2012, FPC discussed the draft RAI with the NRC toconfirm an understanding of the information being requested. On July 5, 2012, the NRC provided aformal RAI required to complete the evaluation of the CR-3 EPU LAR (Reference 3).The attachment, "Response to Second Request for Additional Information -Probabilistic RiskAssessment Licensing Branch Technical Review of the CR-3 EPU LAR," provides the CR-3 formalresponse to the RAI.This correspondence contains no new regulatory commitments.If you have any questions regarding this submittal, please contact Mr. Dan Westcott, Superintendent,Licensing and Regulatory Programs at (352) 563-4796.SSinc rely,Jon A. F nkeVice residentC stal River Nuclear PlantJAF/gweAttachment: Response to Second Request for Additional Information -Probabilistic Risk AssessmentLicensing Branch Technical Review of the CR-3 EPU LARxc: NRR Project ManagerRegional Administrator, Region IISenior Resident InspectorState ContactCrystal River Nuclear Plant15760W. Powerline StreetCrystal River, FL 34428 U.S. Nuclear Regulatory Commission3F0712-08Page 2 of 2STATE OF FLORIDACOUNTY OF CITRUSJon A. Franke states that he is the Vice President, Crystal River Nuclear Plant for FloridaPower Corporation; that he is authorized on the part of said company to sign and file with theNuclear Regulatory Commission the information attached hereto; and that all such statementsmade and matters set forth therein are true and correct to the best of his knowledge, information,and belief.A. FrankeCrystal River Nuclear PlantThe foregoing document was acknowledged before me this .3 /2012, by Jon A. Franke.day of(/Signature of Notary PublicState da. ....r CAROLYN E. POR IN]-* Commission # DD 937"553l1ý Expires March 1, 2014 !_ ", R , , , " Bo ndd Thru Troy F an l mr ft 8 ,.70190,(Print, type, or stamp CommissionedName of Notary Public)PersonallyKnown 11Produced-OR- Identification FLORIDA POWER CORPORATIONCRYSTAL RIVER UNIT 3DOCKET NUMBER 50-302 / LICENSE NUMBER DPR-72ATTACHMENTRESPONSE TO SECOND REQUEST FOR ADDITIONALINFORMATION -PROBABILISTIC RISK ASSESSMENTLICENSING BRANCH TECHNICAL REVIEW OF THE CR-3EPU LAR U.S. Nuclear Regulatory Commission Attachment3F0712-08 Page 1 of 3RESPONSE TO SECOND REQUEST FOR ADDITIONALINFORMATION -PROBABILISTIC RISK ASSESSMENT LICENSINGBRANCH TECHNICAL REVIEW OF THE CR-3 EPU LARBy letter dated June 15, 2011, Florida Power Corporation (FPC) requested a license amendmentto increase the rated thermal power level of Crystal River Unit 3 (CR-3) from 2609 megawatts(MWt) to 3014 MWt (Reference 1). On May 8, 2012, via electronic mail, the NRC provided adraft request for additional information (RAI) needed to support the Probabilistic RiskAssessment (PRA) Licensing (APLA) Branch technical review of the CR-3 Extended PowerUprate (EPU) License Amendment Request (LAR). By teleconference on May 14, 2012, FPCdiscussed the draft RAI with the NRC to confirm an understanding of the information beingrequested. On July 5, 2012, the NRC provided a formal RAI required to complete the evaluationof the CR-3 EPU LAR. For tracking purposes, each item related to this RAI is uniquelyidentified as APLA X-Y, with X indicating the RAI set and Y indicating the sequential itemnumber.APLA 2-1Page 2.13-29 of Attachment 5 to the original LAR dated June 15, 2011, describes the reviewconducted to analyze fire risk for extended power uprate (EPU). This section states that at thetime of LAR evaluation, the cable routing and component location had not been finalized,therefore the impact on fire risk could not be quantified. Also the timing analysis for the newoperator action to lock out the atmospheric dump valve (ADV) actuation had not been performedtherefore, the fire human reliability analysis (HRA) value could not be determined. The FirePRA was updated based only on HRA timing and did not include fire ignition frequency nor fireloading. The concluding sentence states that since HRA timing change due to EPU areinsignificant, it is concluded that there is no significant change in overall fire risk. The NRCstaff requests additional information explaining how the Fire PRA was updated for the EPU.Please provide updated results for the Fire PRA if cable routing, component location and HRAtiming on ADV actuation are now finalized. In addition, please describe how the results for nonmulti compartment fire core damage frequency in Table 2.13-2 of Attachment 5 to the originalLAR dated June 15, 2011, were obtained.Response:To further clarify the FPC response to RAI APLA 1-4 in the FPC to NRC letter dated March 22,2012 (Reference 2); the CR-3 fire PRA model is being significantly updated to support theimplementation of 10 CFR 50.48(c) and National Fire Protection Association (NFPA) Standard805, "Performance-Based Standard for Fire Protection for Light Water Reactor ElectricGenerating Plants, 2001 Edition," (NFPA 805). The fire PRA is based on the guidance ofNUREG/CR-6850, "EPRI/NRC-RES Fire PRA Methodology for Nuclear Power Facilities,"September 2005, (Reference 3) and the model was built using the 2009 internal events model. Apeer review was performed and the open facts and observation findings potentially impactingEPU were provided in Appendix 3 of the FPC to NRC letter dated August 11, 2011(Reference 4).The CR-3 fire PRA model was utilized during the development of the CR-3 EPU LAR toprovide available fire risk insights based upon known EPU design information. To fully quantifycore damage frequency (CDF) and large early release frequency (LERF) resulting from firerelated events, specific design details such as cable type and routing must be known. As such, U.S. Nuclear Regulatory Commission Attachment3F0712-08 Page 2 of 3the calculated non multi compartment fire CDF shown in Table 2.13-2, "Risk Results WithoutRisk Reduction Modifications," of the CR-3 EPU Technical Report (TR) (Reference 1,Attachments 5 and 7) only reflects the revised HRA considering the CR-3 EPU.A complete fire PRA evaluation is comprised of two parts: 1) the effects of a fire within anindividual fire compartment (i.e., non multi compartment); and 2) the effects of a fire within afire compartment and the adjacent compartments (i.e., multi compartment).The impact of the CR-3 EPU on the non multi compartment analysis fire risk contribution wasdetermined using the following process:* Operator actions were adjusted with new timing based upon EPU thermal-hydraulic analysis." HRA values were adjusted for fire impact using the same HRA methodology as the fire PRAbase model; human failure events were evaluated using standard HRA methods asimplemented in the Electric Power Research Institute HRA calculator." The CDF and LERF were requantified for the fire PRA model using the fire adjusted HRAvalues. LERF did not change as a result of the fire adjusted HRA values. The revised CDFfor the non multi compartment analysis was reported in Table 2.13-2 of the CR-3 EPU TR.The fire PRA multi compartment analysis requires details of the location of cables, andcomponents relative to doors, dampers, and penetrations. The location of cables and componentsassociated with certain EPU modifications (e.g., the Inadequate Core Cooling MitigationSystem) has not been finalized; therefore, a multi compartment analysis has not been performedreflecting the CR-3 EPU. A multi compartment analysis is continuing to be developed in supportof the transition of the CR-3 Fire Protection Program (FPP) to NFPA 805 and will consider theCR-3 as-built design at that time, including an analysis of the finalized EPU and other plantmodifications.Deterministic and probabilistic methods have been, and continue to be, utilized in the detaileddesign of the EPU and other plant modifications to minimize the potential increase in plant firerisk. The EPU modifications, including the ADV related modifications, are not expected tosignificantly alter the fire risk conclusions provided in Section 2.13, "Risk Evaluation," of theEPU TR and fire induced events are not expected to be dominant risk contributors to the overallplant CDF or LERF during operation at EPU conditions.A separate LAR regarding the transition of the CR-3 FPP to NFPA 805 will provide updated firePRA results based on plant conditions at that time and will include the multi compartmentanalysis results. Therefore, to avoid duplication of NRC reviews, FPC proposes to not addressthe CR-3 fire PRA further as part of the CR-3 EPU LAR review.References1. FPC to NRC letter dated June 15, 2011, "Crystal River Unit 3 -License AmendmentRequest #309, Revision 0, Extended Power Uprate." (ADAMS Accession No.ML1 12070659)2. FPC to NRC letter dated March 22, 2012, "Crystal River Unit 3 -Response to Request forAdditional Information to Support NRC PRA Licensing Branch Technical Review of the U.S. Nuclear Regulatory Commission Attachment3F0712-08 Page 3 of 3CR-3 Extended Power Uprate LAR (TAC No. ME6527)." (ADAMS Accession No.ML12086A107)3. NUREG/CR 6850, "EPRI/NRC-RES Fire PRA Methodology for Nuclear PowerFacilities," September 2005.4. FPC to NRC letter dated August 11, 2011, "Crystal River Unit 3 -Response to Request forAdditional Information to Support NRC Probabilistic Risk Assessment Licensing BranchAcceptance Review of the CR-3 Extended Power Uprate LAR (TAC No. ME6527)."(ADAMS Accession No. MLI 1234A05 1)