ML14015A139

V. C. Summer, Unit 1, Response to Request for Additional Information Concerning 2012 Annual ECCS Evaluation Model Revisions Report

ML14015A139
Person / Time
Site:	Summer
Issue date:	01/13/2014
From:	Gatlin T D South Carolina Electric & Gas Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC MF2722
Download: ML14015A139 (21)

Text

• 1VThomas D. GatlinVice President, Nuclear Operations803.345.4342A SCANA COMPANYJanuary 13, 2014U.S. Nuclear Regulatory CommissionDocument Control DeskWashington, DC 20555-0001Dear Sir / Madam:Subject: VIRGIL C. SUMMER NUCLEAR STATION (VCSNS), UNIT 1DOCKET NO. 50-395OPERATING LICENSE NO. NPF-12RESPONSE TO REQUEST FOR ADDITIONAL INFORMATIONCONCERNING 2012 ANNUAL ECCS EVALUATION MODELREVISIONS REPORTReferences:1. Thomas D. Gatlin, SCE&G Letter to Document Control Desk, ECCSEvaluation Model Revisions Report, dated June 13, 2013 [ML13169A054]2. Shawn Williams, NRC Letter to Thomas D. Gatlin, Virgil C. Summer NuclearStation, Unit I -Request for Additional Information (TAC NO. MF2722),dated December 2, 2013 [ML13324A813]South Carolina Electric & Gas Company (SCE&G) received a NRC letter datedDecember 2, 2013 (Reference 2), requesting additional information regarding the Virgil C.Summer Nuclear Station Unit 1 annual ECCS Evaluation Model Revisions Report for 2012(Reference 1). SCE&G has reviewed the request for additional information (RAI) and herebysubmits the attached response.If you have any questions or require additional information, please contact Mr. Bruce Thompsonat (803) 931-5042.Very truly yours,Thomas D. GatlinTS/TDG/wmEnclosure -Response to RAI Concerning Annual ECCS Evaluation Model Revisions ReportAttachments (2)c: K. B. MarshS. A. ByrneJ. B. ArchieN. S. CarnsJ. H. HamiltonJ. W. WilliamsW. M. CherryV. M. McCreeS. A. WilliamsNRC Resident InspectorK. M. SuttonNSRCRTS (CR-1 3-05091, LTD 321)File (818.02-17)PRSF (RC-14-0001)Virgil C. Summer Station .Post Office Box 88 -Jenkinsville, SC .29065. F (803) 941-9776 Document Control DeskEnclosureCR-13-05091RC-14-0001Page 1 of 5VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT IDOCKET NO. 50-395OPERATING LICENSE NO. NPF-12ENCLOSUREVIRGIL C. SUMMER NUCLEAR STATION, UNIT NO. I -RESPONSE TO REQUEST FORADDITIONAL INFORMATION CONCERNING 2012 ANNUAL ECCS EVALUATION MODELREVISIONS REPORT (TAC NO. MF2722)

• Document Control DeskEnclosureCR-13-05091RC-14-0001Page 2 of 5REQUESTS FOR ADDITIONAL INFORMATIONEMERGENCY CORE COOLING SYSTEM EVALUATION MODEL REVISIONS REPORTVIRGIL C. SUMMER NUCLEAR STATION, UNIT 1DOCKET NO. 50-395Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.46(a)(3), South CarolinaElectric and Gas Company (the licensee), submitted a report describing "changes andenhancements to the ECCS [emergency core cooling system] Evaluation Models," and anestimate of the effects of the changes and enhancements on the predicted peak claddingtemperature for Virgil C. Summer Nuclear Station, Unit 1. The report was submitted by letterdated June 13, 2013 (Agencywide Documents Access and Management System (ADAMS)Accession No. ML13169A054).Page 6 of 7 of Attachment II to the June 13, 2013, letter lists an "Upflow Conversion" under LineItem B., "Planned Plant Modification Evaluations," with an associated estimated effect onpredicted peak cladding temperature (PCT) estimated as 148 OF.Since 148 OF exceeds the 50 OF threshold at which the NRC defines a significant change andthe submitted report is described as an annual report, it is not clear how this change applies tothe plant nor how the report complies with 10 CFR 50.46(a)(3)(ii) requirements. Thereforeplease provide the following additional information.RAI IProvide a more detailed description of the upflow conversion and explain itsimplementation status.SCE&G ResponseDuring Cycle 16, V. C. Summer experienced fuel failure because of grid to rod fretting. Thisfailure mechanism was initiated by reactor coolant cross-flow jetting through the joints betweenbaffle plates. The susceptibility to this condition was due in part to the reactor internals flowconfiguration.The V. C. Summer reactor vessel lower internals assembly consists of a core barrel into whichbaffle plates, supported by interconnecting former plates, are installed. The original reactorvessel internals configuration incorporated downward coolant flow in the region between thecore barrel and the baffle plates as depicted in Figure 1. Since the flow direction through thebaffle-barrel region was opposite to the direction of the flow through the core, there was an axialpressure gradient across the baffle plates, which varies from a maximum at the top of the core Document Control DeskEnclosureCR-13-05091RC-14-0001Page 3 of 5to a minimum at the bottom of the core. This pressure gradient provided the driving force forcross flow jetting through the joints between baffle plates.In order to substantially reduce the possibility of the baffle jetting, the reactor vessel internalswere field modified during Refuel 18 (Fall 2009) to reverse the secondary coolant flow pattern inthe baffle-barrel region in order to reduce the jet-driving pressure gradient across the bafflejoints. The hardware change for this modification (i.e., Upflow Conversion), consisted-ofplugging the existing flow holes in the core barrel between the top and second former level andmachining new flow holes in the top former plates. These changes resulted in a substantialreduction in the driving force for coolant jetting through the baffle plate joints. Section 4.2.2.2 ofthe V. C. Summer FSAR contains a brief description of the modification and its impact on theflow pattern within the baffle-barrel region.In addition to V. C. Summer, Upflow Conversions have been successfully implemented at anumber of other Westinghouse plants including J. M. Farley Units 1 and 2, Kori Unit 1 in SouthKorea, Point Beach Units 1 and 2, Beaver Valley Unit 1, Ringhals Unit 2 in Sweden, JoseCabrera in Spain, North Anna Unit 1 and Diablo Canyon Unit 2.RAI 2Explain how the June 13, 2013, report, which appears to be the first disclosure of thismodel change to the NRC, satisfies the portion of 10 CFR 50.46(a)(3)(i) requiringsignificant ECCS evaluation model changes to be reported to the NRC in 30 days.SCE&G ResponseThe Westinghouse Electric Company holds the small break loss of coolant accident (SBLOCA)analysis of record for V. C. Summer. To assist SCE&G in meeting the reporting requirements of10 CFR 50.46(a), errors or changes in the Emergency Core Cooling System (ECCS) EvaluationModel (EM) are provided by Westinghouse in accordance with the process outlined in WCAP-13451, Westinghouse Methodology for Implementation of 10 CFR 50.46 Reporting. Forconsistency, the generic WCAP interpretations were applied by SCE&G in responding to thereporting requirements of 10 CFR 50.46 for the Upflow Conversion.As described in the response to Item 3 below, the impact of the Upflow Conversion wasevaluated prior to implementation via execution of the Westinghouse SBLOCA EM. The resultswere utilized in the 10 CFR 50.59 evaluation for the Upflow Conversion. The SBLOCAevaluation included plant specific input values to explicitly model the impact of the UpflowConversion on pre-accident initial conditions. These input changes were not consideredchanges in the Evaluation Model since (1) the SBLOCA Evaluation Model is applied to bothupflow and downflow plants, (2) the input changes were not made to correct a prior error and (3)no modification in a feature of the Evaluation Model or in its application as described to the NRCin licensing documentation resulted. With the Upflow Conversion being a planned change, thepeak clad temperature (PCT) change was not counted toward the accumulation of changespertaining to 10 CFR 50.46 reporting requirements related to a significant change (> 50 OF).Instead, consistent with Section 3.5 of WCAP-1 3451, the PCT change was included in the V. C.

Document Control DeskEnclosureCR-13-05091RC-14-0001Page 4 of 5Summer Nuclear Station 2009 annual report provided to the NRC by SCE&G letter numberRC-10-0073, dated June 7, 2010. The 2009 annual report and three subsequent reportsshowing the Upflow Conversion as a line item on the SBLOCA PCT rack up sheet under LineItem B, "Planned Plant Modification Evaluations," can be found in Attachment 2 of thisresponse. It should be noted, Westinghouse typically shows all changes as planned until a newanalysis of record is performed. In this context, planned does not mean future; it means a plantspecific input change made under 10 CFR 50.59.RAI 3When a significant (i.e., >50 OF) ECCS evaluation model error or change is reported to theNRC, 10 CFR 50.46(a)(3)(ii) requires that "the applicant or licensee shall...include with thereport a proposed schedule for providing a reanalysis or taking other action as may beneeded to show compliance with 50.46 requirements... " Please provide a disposition forthis requirement that is consistent with the response to Items 1) and 2), above.SCE&G ResponseAn evaluation was performed to assess the impact of the V. C. Summer Upflow Conversion onthe current SBLOCA analysis of record using the standard Westinghouse Appendix K SBLOCAEvaluation Model (NOTRUMP-EM; [1], [2] and [3]).The majority of the inputs for the Upflow Conversion remained unchanged from the V. C.Summer SBLOCA analysis of record. Key changes included the plant as an upflow baffle-barrelconfiguration and associated reactor vessel hydraulic and geometric data.A partial break spectrum with an upflow baffle-barrel configuration was evaluated using theNOTRUMP-EM to confirm the limiting break size. Fuel burnup sensitivity studies were alsoperformed for the limiting break size to determine the worst times in life that maximize theresulting PCT and cladding oxidation. The results are summarized in Section 15.3.1.2.7 of theFSAR. Overall, the results demonstrate that the requirements of 1OCFR 50.46 continued to bemet for this planned plant modification.In summary, the impact of the Upflow Conversion for V. C. Summer was evaluated via a partialreanalysis with an approved SBLOCA EM, and results have been incorporated into the V. C.Summer FSAR.

• Document Control DeskEnclosureCR-13-05091RC-14-0001Page 5 of 5References:1. WCAP-1 0079-P-A, Rev. 0, "NOTRUMP -A Nodal Transient Small Break and GeneralNetwork Code," August 1985.2. WCAP-10054-P-A, Rev. 0, "Westinghouse Small Break ECCS Evaluation Model Using theNOTRUMP Code," August 1985.3. WCAP-1 0054-P-A, Addendum 2, Rev. 1, "Addendum to the Westinghouse Small BreakECCS Evaluation Model Using the NOTRUMP Code: Safety Injection into the Broken Loopand COSI Condensation Model," July 1997.

• Document Control DeskAttachment 1CR-13-05091RC-14-0001Page 1 of 2VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT IDOCKET NO. 50-395OPERATING LICENSE NO. NPF-12ATTACHMENT 1FIGURE 1 -V.C. SUMMER BAFFLE-BARREL REGION DOWNFLOW PATH

• Document Control DeskAttachment 1CR- 3-05091RC-14-0001Page 2 of 2REACTOR VESSELCORE BARRELCOLANTCORE REGION/ I N BAFFLE PLATE 7THERMALNEUTRONPADSLO WER COREPLATE NJFigure 1. V. C. Summer Baffle-Barrel Region Downflow Path

-Document Control DeskAttachment 2CR-13-05091RC-14-0001Page 1 of 13VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT IDOCKET NO. 50-395OPERATING LICENSE NO. NPF-12ATTACHMENT 22009 -2012 ECCS Evaluation Model Revisions Reports Thomas D. GatlinVice President, Nuclear Operations803.345.4342A SCAANA COMPANY"June 7,2010Document Control DeskU. S. Nuclear Regulatory CommissionWashington, DC 20555Dear Sir / Madam:Subject: VIRGIL C. SUMMER NUCLEAR STATION UNIT 1DOCKET NO. 50/395OPERATING LICENSE NO. NPF-12ECCS EVALUATION MODEL REVISIONS REPORTSouth Carolina Electric & Gas Company (SCE&G) hereby submits the 2009 EmergencyCore Cooling System (ECCS) Evaluation Model Revisions Annual Report for theVirgil C. Summer Nuclear Station (VCSNS). This report is being submitted pursuantto 10 CFR 50.46, which requires licensees to notify the NRC on at least an annualbasis of corrections to or changes in the ECCS Evaluation Models.Summary sheets describing changes and enhancements to the ECCS EvaluationModels for 2009 are included in Attachment I. Peak Clad Temperature (PCT) sheetsare included in Attachment II.If you have any questions, please call Bruce L. Thompson at (803) 931-5042.Very truly yours,Thomas D. GatlinGARITDG/wmAttachmentsc: K. B. MarshS. A. ByrneJ. B. ArchieN. S. CamsJ. H. HamiltonR. J. WhiteW. M. CherryL. A. ReyesR. E. MartinNRC Resident InspectorK. M. SuttonNSRCRTS (LTD 321, RR 8375)File (818.02-17)PRSF (RC-10-0073)Virgil C. Summer Station -Post Office Box 88 .Jenkinsville, SC .29065. T (803) 345-52099 & o/ v , / '9 0 Document Control DeskAttachment IILTD 321, RR 8375RC-10-0073Page 6 of 7Westinghouse LOCA Peak Clad Temperature Summary for Appendix K Small BreakPlant Name:Utility Name:Revision Date:V. C. SummerSouth Carolina Electric & Gas1/27/10Analysis InformationEM: NOTRUMPFQ: 2.45Fuel: Vantage +Notes:Analysis Date:FdH:SGTP (%):9/12/061.6210Limiting Break Size: 3 InchClad Temp (OF)Ref. NotesLICENSING BASISAnalysis-Of-Record PCT1775 9 (a)PCT ASSESSMENTS (Delta PCT)A. PRIOR ECCS MODEL ASSESSMENTS1. NoneB. PLANNED PLANT MODIFICATION EVALUATIONS1. Upf low ConversionC. 2009 ECCS MODEL ASSESSMENTS1. NoneD. OTHER1. NoneLICENSING BASIS PCT + PCT ASSESSMENTS0148 10,1100PCT = 1923References:1. CGE-94-205, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Notification and Reporting Information," February 8, 1994.2. CGE-94-228, "South Carolina Electric and Gas Company, Virgil C. Summer Station,SBLOCTA Axial Nodalization," October 27, 1994.3. CGE-95-201, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Notification and Reporting Information," February 3, 1995.4. CGE-96-202, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Annual Notification and Reporting," February 9, 1996.5. CGE-96-213, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Small Break LOCA Notification and Reporting," July 8,1996.6. CGE-00-044, "South Carolina Electric and Gas Company, Virgil C. Summer NuclearStation, 10 CFR 50.46 Appendix K (BART / BASH / NOTRUMP) Evaluation Model,Mid-Year Notification and Reporting for 2000," June 30, 2000.7. CGE-03-80, "10 CFR 50.46 Mid-Year Notification and Reporting for 2003," January2004.

-.Document Control DeskAttachment IILTD 321, RR 8375RC-10-0073Page 7 of 78. LTR-LIS-06-344, "Transmittal of Updated V. C. Summer SBLOCA PCT Rackup Sheets,"November 2006.9. LTR-LIS-06-662, Transmittal of V. C. Summer SBLOCTA PCT Rackup Sheets for HHSIThrottle Valve Replacement," November 2006.10. WCAP-1 6980-P, Revision 1, "Reactor Internals Upflow Conversion Program EngineeringReport V. C. Summer Nuclear Station Unit 1," December 2008.11. LTR-LIS-09-18, "10 CFR 50.46 Report for the V. C. Summer (CGE) Upflow ConversionProgram Break LOCA Evaluation," January 2009.Notes:(a) The Rebaseline Analysis includes the impacts of the following model assessments:1. LUCIFER Error Corrections (Ref. 1)2. Effect of SI in Broken Loop (Ref. 1)3. Effect of Improved Condensation Model (Ref. 1)4. Axial Nodalization, RIP Model Revision and SBLOCTA Error CorrectionsAnalysis (Ref. 2)5. Boiling Heat Transfer Error (Ref. 3)6. Steam Line Isolation Logic Error (Ref. 3)7. NOTRUMP Specific Enthalpy Error (Ref. 4)8. SALIBRARY Double Precision Error (Ref. 4)9. SBLOCTA Fuel Rod Initialization Error (Ref. 5)10. NOTRUMP Mixture Level Tracking / Region Depletion Errors (Ref. 6)11. NOTRUMP Bubble Rise / Drift Flux Model Inconsistency Corrections (Ref. 7)12. Refined Break Spectrum (Ref. 8)13. High Head Safety Injection (HHSI) Flow Increase (Ref. 9)

Thomas D. GatlinVice President, Nuclear Operations803.345.4342A SCANA COMPANYJune 6,2011Document Control DeskU. S. Nuclear Regulatory CommissionWashington, DC 20555Dear Sir / Madam:Subject: VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1DOCKET NO. 50/395OPERATING LICENSE NO. NPF-12ECCS EVALUATION MODEL REVISIONS REPORTSouth Carolina Electric & Gas Company (SCE&G), hereby submits the 2010 EmergencyCore Cooling System (ECCS) Evaluation Model Revisions Annual Report for VCSNS.This report is being submitted pursuant to 10 CFR 50.46, which requires licensees tonotify the NRC on at least an annual basis of corrections to or changes in the ECCSEvaluation Models.Summary sheets describing changes and enhancements to the ECCS EvaluationModels for 2010 are included in Attachment I. Peak Clad Temperature (PCT) sheets areincluded in Attachment II.If you have any questions, please call Bruce L. Thompson at (803) 931-5042.Very truly yours,Thomas D. GatlinGAR/TDG/jwAttachmentsc: K. B. MarshS. A. ByrneJ. B. ArchieN. S. CamsJ. H. HamiltonR. J. WhiteW. M. CherryV. M. McCreeR. E. MartinNRC Resident InspectorK. M. SuttonNSRCRTS (LTD 321, RR 8375)File (818.02-17)PRSF (RC-11-0080)Virgil C. Summer Station -Post Office Box 88. Jenkinsville, SC .29065. T (803) 345-5209A A~ A~

Document Control DeskAttachment IILTD 321FIC-1 1-0080Page 6 of 7Westinghouse LOCA Peak Clad Temperature Summary for Appendix K Small BreakPlant Name: V. C. SummerUtility Name: South Carolina Electric & Gas CompanyRevision Date: 1/14/11Analysis InformationEM: NOTRUMPFQ: 2.45Analysis Date: 9/12/06FdH: 1.62SGTP (%): 10Limiting Break Size:3 InchFuel:Notes:Vantage +Clad Temp (OF) Ref. NotesLICENSING BASISAnalysis-Of-Record PCT 1775 9 (a)PCT ASSESSMENTS (Delta PCT)A. PRIOR ECCS MODEL ASSESSMENTS1. None 0B. PLANNED PLANT MODIFICATION EVALUATIONS1. Upflow Conversion 148 10,11C. 2010 ECCS MODEL ASSESSMENTS1. None 0D. OTHER1. None 0LICENSING BASIS PCT + PCT ASSESSMENTS PCT 1923References:1. CGE-94-205, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Notification and Reporting Information," February 8, 1994.2. CGE-94-228, "South Carolina Electric and Gas Company, Virgil C. Summer Station,SBLOCTA Axial Nodalization," October 27,1994.3. CGE-95-201, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Notification and Reporting Information," February 3, 1995.4. CGE-96-202, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Annual Notification and Reporting," February 9, 1996.5. CGE-96-213, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Small Break LOCA Notification and Reporting," July 8, 1996.6. CGE-00-044, "South Carolina Electric and Gas Company, Virgil C. Summer NuclearStation, 10 CFR 50.46 Appendix K (BART / BASH / NOTRUMP) Evaluation Model,Mid-Year Notification and Reporting for 2000," June 30, 2000.7. CGE-03-80, "10 CFR 50.46 Mid-Year Notification and Reporting for 2003,"January 2004.

Document Control DeskAttachment IILTD 321RC-1 1-0080Page 7 of 78. LTR-LIS-06-344, "Transmittal of Updated V. C. Summer SBLOCA PCT RackupSheets," November 2006.9. LTR-LIS-06-662, 'Transmittal of V. C. Summer SBLOCTA PCT Rackup Sheets forHHSI Throttle Valve Replacement," November 2006.10. WCAP-16980-P, Revision 1, "Reactor Internals Upflow Conversion ProgramEngineering Report V. C. Summer Nuclear Station Unit 1," December 2008.11. LTR-LIS-09-1 8, "10 CFR 50.46 Report for the V. C. Summer (CGE) UpflowConversion Program Small Break LOCA Evaluation," January 2009.Notes:(a) The Rebaseline Analysis includes the impacts of the following model assessments:1-LUCIFER Error Corrections (Ref. 1)2-Effect of SI in Broken Loop (Ref. 1)3-Effect of Improved Condensation Model (Ref. 1)4-Axial Nodalization, RIP Model Revision and SBLOCTA Error CorrectionsAnalysis (Ref. 2)5-Boiling Heat Transfer Error (Ref. 3)6-Steam Line Isolation Logic Error (Ref. 3)7-NOTRUMP Specific Enthalpy Error (Ref. 4)8-SALIBRARY Double Precision Error (Ref. 4)9-SBLOCTA Fuel Rod Initialization Error (Ref. 5)10-NOTRUMP Mixture Level Tracking / Region Depletion Errors (Ref. 6)11 -NOTRUMP Bubble Rise / Drift Flux Model Inconsistency Corrections (Ref. 7)12-Refined Break Spectrum (Ref. 8)13-High Head Safety Injection (HHSI) Flow Increase (Ref. 9)

Thomas D. GatlinVice President, Nuclear Operations803.345.4342A SCANA COMPANY June 6, 2012Document Control DeskU. S. Nuclear Regulatory CommissionWashington, DC 20555Dear Sir / Madam:Subject: VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1DOCKET NO. 50/395OPERATING LICENSE NO. NPF-12ECCS EVALUATION MODEL REVISIONS REPORTSouth Carolina Electric & Gas Company (SCE&G), acting for itself and as agent forSouth Carolina Public Service Authority, hereby submits the 2011 Emergency CoreCooling System (ECCS) Evaluation Model Revisions Annual Report for VCSNS. Thisreport is being submitted pursuant to 10 CFR 50.46, which requires licensees to notifythe NRC on at least an annual basis of corrections to or changes in the ECCSEvaluation Models.Summary sheets describing changes and enhancements to the ECCS EvaluationModels for 2011 are included in Attachment I. Peak Clad Temperature (PCT) sheets areincluded in Attachment I1.If you have any questions, please call Bruce L. Thompson at (803) 931-5042.Very truly yours,Thomas D. GatlinGAR/TDG/jwAttachmentsc: K. B. Marsh R. E. MartinS. A. Byrne NRC Resident InspectorJ. B. Archie K. M. SuttonN. S. Carns NSRCJ. H. Hamilton RTS (LTD 321, RR 8375)R. J. White File (818.02-17)W. M. Cherry PRSF (RC-12-0089)V. M. McCreeVirgil C. Summer Station .Post Office Box 88 .Jenkinsville, SC. 29065

• F (803) 345-5209Al l/4IZ O 5L Document Control DeskAttachment IILTD 321RC-12-0089Page 6 of 7Westinghouse LOCA Peak Clad Temperature Summary for Appendix K Small BreakPlant Name: V. C. SummerUtility Name: South Carolina Electric & Gas CompanyRevision Date: 2/20/2012Analysis InformationEM: NOTRUMPFQ: 2.45Fuel: Vantage +Notes:Analysis Date: 9/12/2006FdH: 1.62SGTP (%): 10Limiting Break Size:3 InchLICENSING BASISAnalysis-Of-Record PCTPCT ASSESSMENTS (Delta PCT)A. PRIOR ECCS MODEL ASSESSMENTS1. NoneB. PLANNED PLANT MODIFICATION EVALUATIONS1. Upflow ConversionC. 2011 ECCS MODEL ASSESSMENTS1. NoneD. OTHER1. NoneLICENSING BASIS PCT + PCT ASSESSMENTSClad Temp (°F) Ref. Notes1775 9 (a)0148 10,1100PCT= 1923References:1. CGE-94-205, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Notification and Reporting Information," February 8, 1994.2. CGE-94-228, "South Carolina Electric and Gas Company, Virgil C. Summer Station,SBLOCTA Axial Nodalization," October 27, 1994.3. CGE-95-201, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Notification and Reporting Information," February 3, 1995.4. CGE-96-202, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Annual Notification and Reporting," February 9, 1996.5. CGE-96-213, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Small Break LOCA Notification and Reporting," July 8, 1996.6. CGE-00-044, "South Carolina Electric and Gas Company, Virgil C. Summer NuclearStation, 10 CFR 50.46 Appendix K (BART/ BASH / NOTRUMP) Evaluation Model,Mid-Year Notification and Reporting for 2000," June 30, 2000.7. CGE-03-80, "10 CFR 50.46 Mid-Year Notification and Reporting for 2003,"January 2004.

Document Control DeskAttachment IILTD 321RC-12-0089Page 7 of 78. LTR-LIS-06-344, 'Transmittal of Updated V. C. Summer SBLOCA PCT RackupSheets," November 2006.9. LTR-LIS-06-662, Transmittal of V. C. Summer SBLOCTA PCT Rackup Sheets forHHSI Throttle Valve Replacement," November 2006.10. WCAP-16980-P, Revision 1, "Reactor Internals Upflow Conversion ProgramEngineering Report V. C. Summer Nuclear Station Unit 1," December 2008.11. LTR-LIS-09-18, 10 CFR 50.46 Report for the V. C. Summer (CGE) UpflowConversion Program Small Break LOCA Evaluation," January 2009.Notes:(a) The Rebaseline Analysis includes the impacts of the following model assessments:1-LUCIFER Error Corrections (Ref. 1)2-Effect of SI in Broken Loop (Ref. 1)3-Effect of Improved Condensation Model (Ref. 1)4-Axial Nodalization, RIP Model Revision and SBLOCTA Error CorrectionsAnalysis (Ref. 2)5-Boiling Heat Transfer Error (Ref. 3)6-Steam Line Isolation Logic Error (Ref. 3)7-NOTRUMP Specific Enthalpy Error (Ref. 4)8-SALIBRARY Double Precision Error (Ref. 4)9-SBLOCTA Fuel Rod Initialization Error (Ref. 5)10-NOTRUMP Mixture Level Tracking / Region Depletion Errors (Ref. 6)S11-NOTRUMP Bubble Rise / Drift Flux Model Inconsistency Corrections (Ref. 7)12-Refined Break Spectrum (Ref. 8)13-High Head Safety Injection (HHSI) Flow Increase (Ref. 9)

Thomas D. GatlinVice President, Nuclear Operations803.345.4342A SCANA COMPANY June 13, 2013Document Control DeskU. S. Nuclear Regulatory CommissionWashington, DC 20555Dear Sir / Madam:Subject: VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1DOCKET NO. 50-395OPERATING LICENSE NO. NPF-12ECCS EVALUATION MODEL REVISIONS REPORTSouth Carolina Electric & Gas Company (SCE&G), acting for itself and as agent forSouth Carolina Public Service Authority, hereby submits the 2012 Emergency CoreCooling System (ECCS) Evaluation Model Revisions Annual Report for VCSNS. Thisreport is being submitted pursuant to 10 CFR 50.46, which requires licensees to notifythe NRC on at least an annual basis of corrections to or changes in the ECCSEvaluation Models.Summary sheets describing changes and enhancements to the ECCS EvaluationModels for 2012 are included in Attachment I. Peak Clad Temperature (PCT) sheets areincluded in Attachment II.If you have any questions, please call Bruce L. Thompson at (803) 931-5042.Very truly yours,Thomas D. GatlinTS/TDG/wmAttachmentsc: K. B. Marsh E. A. BrownS. A. Byrne NRC Resident InspectorJ. B. Archie K. M. SuttonN. S. Cams NSRCJ. H. Hamilton RTS (LTD 321, RR 8375)J. W. Williams File (818.02-17)W. M. Cherry PRSF (RC-13-0080)V. M. McCreeVirgil C. Summer Station .Post Office Box 88. Jenkinsville, SC. 29065

• F (803) 345-5209 Document Control DeskAttachment IILTD 321RC-1 2-0080Page 6 of 7Westinghouse LOCA Peak Clad Temperature Summary for Appendix K Small BreakPlant Name:Utility Name:Revision Date:V. C. SummerSouth Carolina Electric & Gas3/1/2013Analysis InformationEM: NOTRUMPFQ: 2.45Fuel: Vantage +Notes:Analysis Date: 9/12/2006FdH: 1.62SGTP(%): 10Limiting Break Size: 3 InchClad Temp (°F)Ref. NotesLICENSING BASISAnalysis-Of-Record PCT1775 9 (a)PCT ASSESSMENTS (Delta PCT)A. PRIOR ECCS MODEL ASSESSMENTS1. NoneB. PLANNED PLANT MODIFICATION EVALUATIONS1. Upflow ConversionC. 2012 ECCS MODEL ASSESSMENTS1. NoneD. OTHER1. NoneLICENSING BASIS PCT + PCT ASSESSMENTS0148 10,1100PCT = 1923References:1. CGE-94-205, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Notification and Reporting Information," February 8, 1994.2. CGE-94-228, "South Carolina Electric and Gas Company, Virgil C. Summer Station,SBLOCTA Axial Nodalization," October 27, 1994.3. CGE-95-201, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Notification and Reporting Information," February 3, 1995.4. CGE-96-202, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Annual Notification and Reporting," February 9, 1996.5. CGE-96-213, "South Carolina Electric and Gas Company, Virgil C. Summer Station,10 CFR 50.46 Small Break LOCA Notification and Reporting," July 8, 1996.6. CGE-00-044, "South Carolina Electric and Gas Company, Virgil C. Summer NuclearStation, 10 CFR 50.46 Appendix K (BART / BASH / NOTRUMP) Evaluation Model,Mid-Year Notification and Reporting for 2000," June 30, 2000.7. CGE-03-80, "10 CFR 50.46 Mid-Year Notification and Reporting for 2003," January 2004.8. LTR-LIS-06-344, "Transmittal of Updated V. C. Summer SBLOCA PCT Rackup Sheets,"November 2006.9. LTR-LIS-06-662, Transmittal of V. C. Summer SBLOCTA PCT Rackup Sheets for HHSIThrottle Valve Replacement," November 2006.10. WCAP-16980-P, Revision 1, "Reactor Internals Upflow Conversion Program EngineeringReport V. C. Summer Nuclear Station Unit 1," December 2008.11. LTR-LIS-09-18, "10 CFR 50.46 Report for the V. C. Summer (CGE) Upflow Conversion Document Control DeskAttachment IILTD 321RC-1 2-0080Page 7 of 7Program Small Break LOCA Evaluation," January 2009.Notes:(a) The Rebaseline Analysis includes the impacts of the following model assessments:1-LUCIFER Error Corrections (Ref. 1)2-Effect of SI in Broken Loop (Ref. 1)3-Effect of Improved Condensation Model (Ref. 1)4-Axial Nodalization, RIP Model Revision and SBLOCTA Error Corrections Analysis (Ref. 2)5-Boiling Heat Transfer Error (Ref. 3)6-Steam Line Isolation Logic Error (Ref. 3)7-NOTRUMP Specific Enthalpy Error (Ref. 4)8-SALIBRARY Double Precision Error (Ref. 4)9-SBLOCTA Fuel Rod Initialization Error (Ref. 5)10-NOTRUMP Mixture Level Tracking / Region Depletion Errors (Ref. 6)11-NOTRUMP Bubble Rise / Drift Flux Model Inconsistency Corrections (Ref. 7)12-Refined Break Spectrum (Ref. 8)13-High head safety injection (HHSI) flow increase (Ref. 9)