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, 2007 Mr. M. R. Blevins Senior 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 OF FINITE 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 Confirmatory Action 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 [Finite Element 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 staffs 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 no longer 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 commitment letter regarding enhanced inspection and leakage monitoring requirements for the reactor 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 Policy and 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 or Enforcement 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 NRCs 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 Regulation Docket No. 50-446 cc: See next page

ML072420055 OFFICE DCI/CPNB DCI/CPNB LPL4/PM LPL4/LA LPL4/BC NAME TLupold TChan BSingal JBurkhardt Thiltz, BKS for DATE 9/6/07 9/6/07 9/5/07 9/5/07 9/5/07 OFFICE DCI/D DRP/D, RGN4 DORL/D NAME MEvans DChamberlain CHaney DATE 9/7/07 9/7/07 WJones for DC 9/7/07 Comanche Peak Steam Electric Station cc:

Senior Resident Inspector Mr. Richard A. Ratliff, Chief U.S. Nuclear Regulatory Commission Bureau of Radiation Control P.O. Box 2159 Texas Department of Health Glen Rose, TX 76403-2159 1100 West 49th Street Austin, TX 78756-3189 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission Mr. Brian Almon 611 Ryan Plaza Drive, Suite 400 Public Utility Commission Arlington, TX 76011 William B. Travis Building P.O. Box 13326 Mr. Fred W. Madden, Director 1701 North Congress Avenue Regulatory Affairs Austin, TX 78701-3326 TXU Generation Company LP P.O. Box 1002 Ms. Susan M. Jablonski Glen Rose, TX 76043 Office of Permitting, Remediation and Registration George L. Edgar, Esq. Texas Commission on Environmental Morgan Lewis Quality 1111 Pennsylvania Avenue, NW MC-122 Washington, DC 20004 P.O. Box 13087 Austin, TX 78711-3087 County Judge P.O. Box 851 Mr. Anthony P. Jones Glen Rose, TX 76043 Chief Boiler Inspector Texas Department of Licensing Environmental and Natural and Regulation Resources Policy Director Boiler Division Office of the Governor E.O. Thompson State Office Building P.O. Box 12428 P.O. Box 12157 Austin, TX 78711-3189 Austin, TX 78711 September 2007