NOC-AE-07002196, CFR50.46 Annual Report of ECCS Model Revisions

CFR50.46 Annual Report of ECCS Model Revisions

ML072570097
Person / Time
Site:	South Texas
Issue date:	09/04/2007
From:	Leazar D South Texas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NOC-AE-07002196
Download: ML072570097 (4)

Text

Nuclear Operating Company South Texas Pro/ca Electric Generating Station PO.Bow 289 Wadsworth. Texas 77483 September 4, 2007 NOC-AE-07002196 10CFR50.46 U. S. Nuclear Regulatory Commission Attention: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 South Texas Project Units I & 2 Docket Nos. STN 50-498, STN 50-499 10CFR50.46 Annual Report of ECCS Model Revisions

References:

1. Letter from D. A. Leazar to NRC Document Control Desk, "1 OCFR5 0.46 Annual Report of ECCS Model Revisions," dated February 11, 2003 (NOC-AE-03001464, ML030500320)

2. Letter from D. A. Leazar to NRC Document Control Desk, "10CFR50.46 Annual Report of ECCS Model Revisions," dated September 18, 2006 (NOC-AE-06002064, ML062690497)

Pursuant to I OCFR50.46(a)(3)(ii), STP Nuclear Operating Company (STPNOC) submits this report concerning revisions to the accepted Emergency Core Cooling System (ECCS) evaluation model at South Texas Project (STP) Units 1 and 2.

The STP Unit I and Unit 2 Small Break LOCA peak clad temperatures (PCT) are unchanged from those reported in the previous report (Reference 2): 1612'F STPNOC has determined that the rebaseline described in Reference I was a reanalysis to establish a new Analysis of Record for Large Break LOCA with a PCT of 2136 'F. Corrections to the STP Unit 1 and Unit 2 Large Break LOCA analyses resulted in a PCT of 2112'F, as described in the attachment. The change is less than the 50'F criterion for reanalysis in I OCFR50.46(a)(3)(ii).

There are no commitments in this submittal.

STI: 32188233

NOC-AE-07002196 Page 2 of 3 If you should have any questions concerning this matter, please contact Mr. A. W. Harrison at (361) 972-7298 or me at (361) 972-7795.

David A. L~ea Manager, Fuels & Analysis

Attachment:

Peak Clad Temperature Summary for Appendix K Large Break LOCA

NOC-AE-07002196 Page 3 of 3 cc:

(paper copy) (electronic copy)

Regional Administrator, Region IV A. H. Gutterman, Esquire U. S. Nuclear Regulatory Commission Morgan, Lewis & Bockius LLP 611 Ryan Plaza Drive, Suite 400 Arlington, Texas 76011-8064 Mohan C. Thadani U. S. Nuclear Regulatory Commission Mohan C. Thadani Thad Hill Senior Project Manager Eddy Daniels U.S. Nuclear Regulatory Commission Marty Ryan One White Flint North (MS 7 Dl) Harry Holloway 11555 Rockville Pike Steve Winn Rockville, MD 20852 NRG South Texas LP Senior Resident Inspector Ed Alarcon U. S. Nuclear Regulatory Commission J. J. Nesrsta P. 0. Box 289, Mail Code: MN 16 R. K. Temple Wadsworth, TX 77483 Kevin Pollo City Public Service C. M. Canady Jon C. Wood City of Austin Cox Smith Matthews Electric Utility Department 721 Barton Springs Road C. Kirksey Austin, TX 78704 City of Austin Richard A. Ratliff Bureau of Radiation Control Texas Department of State Health Services 1100 West 49th Street Austin, TX 78756-3189

NOC-AE-07002196 Page,1 of 1 Attachment Peak Clad Temperature Summary for Appendix K Large Break LOCA South Texas Units 1 & 2 Analysis Information:

Analysis Date: 12/17/2002 Evaluation Model: BASH Limiting Break Size: Cd=0.8, Min SI FQ: 2.55 FdH: 1.62 Fuel: RFA /Vantage 5H Steam Generator Tube Plugging (%): 10 Notes: RFA Re-analysis - FdH = 1.55 for Once Burned Standard Fuel Licensing Basis Analysis-Of-Record (AOR) PCT*: 2136 OF PCT Assessments (Delta PCT)

A. Prior ECCS Model Assessments I . IMP Database Error Corrections: 0

2. PAD Version 4.0 Implementation: -30°F B. Planned Plant Modification Evaluations I . None C. 2007 ECCS MODEL ASSESSMENTS I . LOCBART Pellet Volumetric Heat Generation Rate: 6 OF Licensing Basis PCT + PCT Assessments PCT: 2112 OF As noted in the cover letter, STPNOC has determined that the rebaseline performed in 2002 established a new AOR. The new AOR PCT of 2136 °F was calculated from 2090 °F (1998 AOR) + 46 °F (2002 Rebaseline).