ML072420004

Palo Verde Nuclear Generating 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-07-004

ML072420004
Person / Time
Site:	Palo Verde
Issue date:	09/07/2007
From:	Catherine Haney Plant Licensing Branch III-2
To:	Edington R K Arizona Public Service Co
Markley, M T, NRR/DORL/LP4, 301-415-5723
References
TAC MD4170, NRR-07-004
Download: ML072420004 (4)

Text

September 7, 2007Mr. Randall K. EdingtonSenior Vice President, Nuclear Mail Station 7602 Arizona Public Service Company P. O. Box 52034 Phoenix, AZ 85072-2034

SUBJECT:

PALO VERDE NUCLEAR GENERATING 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-07-004 (TAC NO. MD4170)

Dear Mr. Edington:

On March 15, 2007, the U.S. Nuclear Regulatory Commission (NRC) issued ConfirmatoryAction Letter (CAL) No. NRR-07-004 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML070660298) regarding dissimilar metal welds in the pressurizer surge, spray, and safety/relief nozzle-to-safe end welds at Palo Verde Nuclear Generating Station (Palo Verde), Unit 2. The CAL and the supporting commitment letter (ADAMS Accession No. ML070590212) 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 2, 2007 (ADAMS Accession No. ML072410203), 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 Palo Verde, 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 Palo Verde, Unit 2 must be performed prior to exiting your scheduled spring 2008 refueling outage. All other requirements of the CAL and the supporting commitment letter regarding enhanced inspection and leakage monitoring requirements for the reactor coolant system and associated reports remain valid.

R. K. Edington-2-The CAL will remain open until all CAL commitments pertaining to Palo Verde, Units 1, 2, and 3are 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 Title 10 of the Code of Federal Regulations, Part 2, Section 390, of theNRC'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. 50-529 cc: See next page

ML072420004OFFICEDCI/CPNBDCI/CPNBLPL4/PMLPL4/LALPL4/BCNAMETLupoldTChanMMarkleyJBurkhardtThiltz, BKS for DATE9/6/079/6/079/6/079/5/079/6/07 OFFICEDCI/DDRP/D, RGN4DORL/D NAMEMEvansDChamberlainCHaney DATE9/7/079/7/07 Wjones for9/7/07 August 2007Palo Verde Nuclear Generating Station cc:Mr. Steve Olea Arizona Corporation Commission 1200 W. Washington Street Phoenix, AZ 85007Mr. Douglas Kent PorterSenior Counsel Southern California Edison Company Law Department, Generation Resources P.O. Box 800 Rosemead, CA 91770Senior Resident InspectorU.S. Nuclear Regulatory Commission P.O. Box 40 Buckeye, AZ 85326Regional Administrator, Region IVU.S. Nuclear Regulatory Commission Harris Tower & Pavillion 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064ChairmanMaricopa County Board of Supervisors 301 W. Jefferson, 10th Floor Phoenix, AZ 85003Mr. Aubrey V. Godwin, DirectorArizona Radiation Regulatory Agency 4814 South 40 Street Phoenix, AZ 85040Mr. Scott Bauer, Acting General ManagerRegulatory Affairs and Performance Improvement Palo Verde Nuclear Generating Station Mail Station 7636 P.O. Box 52034 Phoenix, AZ 85072-2034Mr. Matthew BenacAssistant Vice President Nuclear & Generation Services El Paso Electric Company 340 East Palm Lane, Suite 310 Phoenix, AZ 85004Mr. John TaylorPublic Service Company of New Mexico 2401 Aztec NE, MS Z110 Albuquerque, NM 87107-4224Mr. Geoffrey M. CookSouthern California Edison Company 5000 Pacific Coast Hwy Bldg D21 San Clemente, CA 92672Mr. Robert HenrySalt River Project 6504 East Thomas Road Scottsdale, AZ 85251Mr. Jeffrey T. WeikertAssistant General Counsel El Paso Electric Company Mail Location 167 123 W. Mills El Paso, TX 79901Mr. John SchumannLos Angeles Department of Water & Power Southern California Public Power Authority P.O. Box 51111, Room 1255-C Los Angeles, CA 90051-0100Mr. Brian AlmonPublic Utility Commission William B. Travis Building P.O. Box 13326 1701 North Congress Avenue Austin, TX 78701-3326Ms. Karen O'ReganEnvironmental Program Manager City of Phoenix Office of Environmental Programs 200 West Washington Street Phoenix AZ 85003