ML072420055

Evaluation of Finite Element Analysis in Support of Alloy 82/182 Pressurizer Butt Weld Inspections in 2008 as Provided by Confirmatory Action Letter CAL NRR-07-007

ML072420055
Person / Time
Site:	Comanche Peak
Issue date:	09/07/2007
From:	Catherine Haney Plant Licensing Branch III-2
To:	Blevins M TXU Power
singal, balwant NRR/DORL 301-415-3016
References
TAC MD4144, NRR-07-007
Download: ML072420055 (4)

Text

September 7, 2007Mr. M. R. BlevinsSenior Vice President

& Chief Nuclear Officer TXU Power Comanche Peak Steam Electric Station ATTN: Regulatory Affairs P.O. Box 1002 Glen Rose, TX 76043

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION, UNIT 2 - EVALUATION OFFINITE ELEMENT ANALYSIS IN SUPPORT OF ALLOY 82/182 PRESSURIZER BUTT WELD INSPECTIONS IN 2008 AS PROVIDED BY CONFIRMATORY ACTION LETTER NRR-07-007 (TAC NO. MD4144)

Dear Mr. Blevins:

On March 20, 2007, the U.S. Nuclear Regulatory Commission (NRC) issued ConfirmatoryAction Letter (CAL) No. NRR-07-007 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML070730620) regarding dissimilar metal welds in the pressurizer surge, spray, and safety/relief nozzle-to-safe end welds at Comanche Peak Steam Electric Station (CPSES), Unit 2. The CAL and the supporting commitment letter (ADAMS Accession No. ML070530211) indicate that inspection and mitigation actions may be conducted during your spring 2008 refueling outage, contingent on the industry providing an analysis that demonstrates an acceptable level of safety to the NRC for the operation of these welds until spring 2008. This letter acknowledges receipt of your letter dated August 3, 2007 (ADAMS Accession No. ML072250091), informing the NRC that the analysis referred to by this CAL and the supporting commitment letter has been completed, and that the analysis is applicable to your plant.The NRC received MRP-216, Rev. 1, "Materials Reliability Program: Advanced FEA [FiniteElement Analysis] Evaluation of Growth of Postulated Circumferential PWSCC [Primary Water Stress-Corrosion Cracking] Flaws in Pressurizer Nozzle Dissimilar Metal Welds," on August 13, 2007 (ADAMS Accession No. ML072410235). Based on our review of this report, the NRC concludes that the analysis provides adequate justification to permit inspections during your spring 2008 refueling outage, and that the analysis is applicable to CPSES, Unit 2. The results of the staff's review are contained in a safety assessment dated August 31, 2007 (ADAMS Accession No. ML072400199), and the associated contractor report (ADAMS Accession No. ML072470394). Based on the above, the NRC concludes that a plant shutdown by December 31, 2007, is nolonger required. Therefore, the pressurizer surge, spray, and safety/relief nozzle-to-safe end Alloy 82/182 butt weld inspections for CPSES, Unit 2 must be performed prior to exiting your scheduled spring 2008 refueling outage. All other requirements of the CAL and the supporting M. R. Blevins-2-commitment letter regarding enhanced inspection and leakage monitoring requirements for thereactor coolant system and associated reports remain valid.The CAL will remain open until all CAL commitments pertaining to CPSES, Unit 2 are complete.

Current NRC guidance regarding CALs is contained in the NRC Enforcement Policyand the NRC Enforcement Manual, which are available at the NRC web site at http://www.nrc.gov/about-nrc/regulatory/enforcement.html (click on Enforcement Policy orEnforcement Guidance) or by contacting the Government Printing Office (GPO) toll-free at 1-888-293-6498. The GPO is open from 7:00 a.m. to 9:00 p.m. EST, Monday through Friday (except Federal holidays).In accordance with Section 2.390 of Title 10 of the Code of Federal Regulations of the NRC's"Rules of Practice," a copy of this letter will be made available electronically for public inspection in the NRC Public Document Room or from the NRC's document system (ADAMS),

accessible from the NRC Web site at http://www.nrc.gov/reading-rm.html

.Sincerely,/RA/Catherine Haney, Director Division of Operating Reactor Licensing Office of Nuclear Reactor RegulationDocket No. 50-446 cc: See next page

ML072420055 OFFICEDCI/CPNBDCI/CPNBLPL4/PMLPL4/LALPL4/BCNAMETLupoldTChanBSingalJBurkhardtThiltz, BKS for DATE9/6/079/6/079/5/079/5/079/5/07 OFFICEDCI/DDRP/D, RGN4DORL/D NAMEMEvansDChamberlainCHaney DATE9/7/079/7/07 WJones for DC9/7/07 September 2007Comanche Peak Steam Electric Station cc:Senior Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 2159 Glen Rose, TX 76403-2159Regional Administrator, Region IVU.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011Mr. Fred W. Madden, DirectorRegulatory Affairs TXU Generation Company LP P.O. Box 1002 Glen Rose, TX 76043George L. Edgar, Esq.Morgan Lewis 1111 Pennsylvania Avenue, NW Washington, DC 20004County JudgeP.O. Box 851 Glen Rose, TX 76043Environmental and Natural Resources Policy Director Office of the Governor P.O. Box 12428 Austin, TX 78711-3189Mr. Richard A. Ratliff, ChiefBureau of Radiation Control Texas Department of Health 1100 West 49th Street Austin, TX 78756-3189Mr. Brian AlmonPublic Utility Commission William B. Travis Building P.O. Box 13326 1701 North Congress Avenue Austin, TX 78701-3326Ms. Susan M. JablonskiOffice of Permitting, Remediation and Registration Texas Commission on Environmental Quality MC-122 P.O. Box 13087 Austin, TX 78711-3087Mr. Anthony P. JonesChief Boiler Inspector Texas Department of Licensing and Regulation Boiler Division E.O. Thompson State Office Building P.O. Box 12157 Austin, TX 78711