IR 05000530/2010010

Followup of License Renewal Unresolved Item - Inspection Report 05000528; 05000529; 05000530-10-010

ML102180239
Person / Time
Site:	Palo Verde
Issue date:	08/05/2010
From:	O'Keefe N F NRC/RGN-IV/DRS/EB-2
To:	Edington R K Arizona Public Service Co
References
IR-10-010
Download: ML102180239 (10)

Text

August 5, 2010

Randall K. Edington, Executive Vice President, Nuclear/CNO Mail Station 7602 Arizona Public Service Company P.O. Box 52034, Mail Stop 7602 Phoenix, AZ 85072-2034

SUBJECT: PALO VERDE NUCLEAR GENERATING STATION - FOLLOWUP OF LICENSE RENEWAL UNRESOLVED ITEM - INSPECTION REPORT 05000528; 05000529; 05000530/2010010

Dear Mr. Edington:

On July 29, 2010, the U.S. Nuclear Regulatory Commission (NRC) completed review of two unresolved items documented in Inspection Report 05000528; 05000529; 05000530/2010007.

These unresolved items related to concerns regarding whether your staff had accounted for industry operating experience related to metal-enclosed bus ducts and the frequency and scope of your structures monitoring program. The enclosed report documents the inspection findings which were discussed with Ms. A. Krainik, Project Manager, License Renewal, and other members of your staff.

This inspection examined activities related to your application for a renewed license for Palo Verde Nuclear Generating Station. The inspection evaluated the completion of baseline structural inspections and the frequency for performing these inspections. In addition, the inspection evaluated whether a recent failure of your metal-enclosed bus ducts should have resulted in a change to your aging management programs. As part of the inspection, the NRC examined procedures and representative records and interviewed personnel.

As a result of our review we have concluded that the accelerated reviews to identify the current condition of your structures and the changes that increased the frequency of monitoring of structures provided reasonable assurance that you had established processes that would manage the effects of aging of your structures. Further, we have concluded the failure of the metal enclosed bus ducts resulted in no required changes to your management programs.

In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter, and its enclosure, will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records component of NRC's document system (ADAMS). ADAMS

Arizona Public Service Company - 2 -

is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,/RA/ Neil O'Keefe, Chief Engineering Branch 2 Division of Reactor Safety

Dockets: 50-528; 50-529; 50-530 Licenses: NPF-41; NPF-51; NPF-74 NRC Inspection Report 50-528; 50-529; 50-530/2010010

w/Attachment:

Supplemental Information cc w/enclosure Mr. Steve Olea Arizona Corporation Commission 1200 W. Washington Street Phoenix, AZ 85007

Mr. Douglas K. Porter, Esq Southern California Edison Company 2244 Walnut Grove Avenue Rosemead, CA 91770

Chairman Maricopa County Board of Supervisors 301 W. Jefferson, 10th Floor Phoenix, AZ 85003

Mr. Aubrey V. Godwin, Director Arizona Radiation Regulatory Agency 4814 South 40 Street Phoenix, AZ 85040 Mr. Dwight C. Mims Vice President Regulatory Affairs and Plant Improvement Palo Verde Nuclear Generating Station Mail Station 7605 P.O. Box 52034 Phoenix, AZ 85072-2034

Chairman, Board of Supervisors 301 W. Jefferson, 10 th Floor Phoenix, AZ 85040

Ronald A. Barnes, Director Regulatory Affairs Palo Verde Nuclear Generating Station MS 7638 P.O. Box 52034 Phoenix, AZ 85072-2034

Arizona Public Service Company - 3 -

Mr. Jeffrey T. Weikert Assistant General Counsel El Paso Electric Company Mail Location 167 123 W. Mills El Paso, TX 79901

Michael S. Green Senior Regulatory Counsel Pinnacle West Capital Corporation P.O. Box 52034, MS 8695 Phoenix, AZ 85072-2034

Mr. Eric Tharp Los Angeles Department of Water & Power Southern California Public Power Authority P.O. Box 51111, Room 1255-C Los Angeles, CA 90051-0100

Mr. James Ray Public Service Company of New Mexico 2401 Aztec NE, MS Z110 Albuquerque, NM 87107-4224

Mr. Geoffrey M. Cook Southern California Edison Company 5000 Pacific Coast Hwy. Bldg. D21 San Clemente, CA 92672

Mr. Robert Henry Salt River Project 6504 East Thomas Road Scottsdale, AZ 85251

Mr. Brian Almon Public Utility Commission William B. Travis Building P.O. Box 13326 Austin, TX 78701-3326

Environmental Program Manager City of Phoenix Office of Environmental Programs 200 West Washington Street Phoenix, AZ 85003

Mr. John C. Taylor Director, Nuclear Generation El Paso Electric Company 340 East Palm Lane, Suite 310 Phoenix, AZ 85004

Chief, Technological Hazards Branch FEMA Region IX 1111 Broadway, Suite 1200 Oakland, CA 94607-4052 Enclosure U.S. NUCLEAR REGULATORY COMMISSION REGION IV Docket: 05000528; 050000529; 05000530 License: NPF-41; NPF-51; NPF-74 Report: 05000528/2010010; 05000529/2010010; 05000530/2010010 Licensee: Arizona Public Service Company Facility: Palo Verde Nuclear Generating Station Location: 5951 S. Wintersburg Rd Tonopah, Arizona Dates: May 1 through July 29, 2010 Inspector: G. Pick, Senior Reactor Inspector Approved By: Neil O'Keefe, Chief Engineering Branch 2 Division of Reactor Safety Enclosure

SUMMARY OF FINDINGS

IR 05000528/2010010; 05000529/2010010; 05000530/2010010; 05/01/2010 - 07/29/2010; Palo Verde Nuclear Generating Station, Followup of License Renewal Unresolved Items

The report covered a 3-month period of inoffice review and evaluation by a senior regional inspector.

Cornerstone: Mitigating Systems

No findings were identified.

B. Licensee-Identified Violations

No findings were identified.

REPORT DETAILS

4OA5 Other - License Renewal

.1 (Closed) Unresolved Item 05000528; 05000529; 05000530/2010007-01:

Impact of Recent Operating Experience on Metal-Enclosed Bus Program

Subsequent to completing the onsite portion of the license renewal inspection, on March 7, 2010, Unit 1 tripped when a ground fault occurred on Bus 1E-NAN-A03 connecting the Nonclass 1E 13.8 kV Bus 1E-NAN-S01 to Breaker 1E-NAN-S03B. Because of heavy rains, water intruded past the cover protecting the nonsegregated bus. The applicant preliminarily concluded the fault resulted from an improperly installed bus duct cover and a breakdown in the Noryl insulation because of aging mechanisms.

The applicant had not completed their evaluation of this event, which included the cause(s).

During this inspection, the inspector reviewed the laboratory evaluation report of the remaining portions of the bus duct and the applicants root cause evaluation report. The inspector interviewed the team leader and personnel responsible for the Metal-Enclosed Bus Aging Management Program.

The inspector concluded that the causes identified for the failure in this bus duct would not have changed the methods employed by the applicant to monitor for the effects of aging since aging was not a contributing cause of the fault. Further, from review of the root cause analysis report planned corrective actions, the inspector determined that the applicant had corrective maintenance work orders scheduled to be implemented during future refueling outages to replace the Noryl insulation.

This unresolved item is closed.

.2 (Closed) Unresolved Item 05000528; 05000529; 05000530/2010007-02:

Structures Monitoring Frequency and Scope

During the onsite inspection, the license renewal inspection team had identified concerns related to the proposed inspection frequency and scope of the structures inspections. The applicant had not established an inspection program that reflected the frequencies specified in American Concrete Institute 349.3R-96, "Evaluation of Existing Nuclear Safety-Related Concrete Structures," and NUREG-1801, "Generic Aging Lessons Learned (GALL) Report - Tabulation of Results," Volume 2, Revision 1. These standards specified that structures exposed to the elements and those inside primary containment should be inspected every 5 years, and that other interior structures should be inspected every 10 years. In addition, the license renewal inspection team had

concerns because the applicant had not completed a 100 percent inspection of all structures to establish a baseline for comparison to future inspection results. The applicant documented these concerns in Condition Report Disposition Request 3441953.

In response to the team's concern, the applicant provided a supplemental response to Request for Additional Information B2.1.32-1, as documented in License Renewal Application Amendment 13, dated April 1, 2010. The applicant revised Commitment 34 in Table A.4-1, "License Renewal Commitments," to state that prior to the period of extended operation, the Palo Verde Structures Monitoring program will be enhanced to inspect structures within the scope of license renewal at 10-year intervals. The team concluded that the applicant had provided an appropriate response for internal structures, excluding primary containment. However, the team continued to have concerns with the applicant's assessment regarding external structures and structures inside containment and concerns with a lack of baseline inspection.

During this inspection, the inspector reviewed the applicant's supplemental responses, reviewed corrective action documents and discussed plans for completing the baseline inspections with the applicant.

As reflected in Letter 102-06194, "Responses to April 28, 2010, Request for Additional Information (RAI) and Follow-up RAIs, for the Review of the PVNGS [Palo Verde Nuclear Generating Station] License Renewal Application, and License Renewal Application Amendment No. 15," dated May 21, 2010, the applicant revised their structures monitoring program commitment to inspect external structures and those structures inside containment at 5-year intervals with the exception of a specific list of nonsafety-related structures. The inspector found this response satisfied the original concerns regarding the inspection frequency.

The inspector reviewed the applicant's plans to complete the inspection and evaluation of their structures onsite prior to the period of extended operation. In Condition Report Disposition Request 3439970, the applicant established an action plan to inspect the remaining structures by the end of 2015. In addition, the applicant established a plan to complete a second 100 percent inspection of the onsite structures during the subsequent 10-year period that would end in 2025 prior to entry into the period of extended operation.

The inspector found that these corrective actions appropriately addressed the identified concerns.

This unresolved item is closed.

4OA6 Meetings

Exit Meeting Summary

On July 29, 2010, the inspector presented the results of the in-office inspection of the structural inspection program reviews to Ms. A. Krainik, Project Manager, License Renewal and other members of the applicant's staff. The applicant acknowledged the issues presented. The inspector asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identified.

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee Personnel

A. Krainik, Project Manager, License Renewal

F. Oreshack, Licensing Engineer

K. Schrecker, Section Leader

LIST OF ITEMS

CLOSED

Closed

05000528,

05000529,

05000530/FIN-2010007-01 URI Impact of Recent Operating Experience on Metal-Enclosed Bus Program (Section 4OA5.1)

05000528,

05000529,

05000530/FIN-2010007-02 URI Structures Monitoring Frequency and Scope (Section 4OA5.2)

LIST OF DOCUMENTS REVIEWED

4OA5.1 Impact of Recent Operating Experience on Metal Enclosed Bus Program Aging Management Program for Metal Enclosed Bus - B2.1.36, Revision 4

Drawing

LR-PVNGS-ELEC-E-MAA-001, "Main Single Line Diagram," Revision 0

Significant Root Cause Investigation Report of the Unit 1 Calvert Bus 1ENANA03 Bus Failure and Reactor Trip

Test Report

APS-90390, "Testing of Sections of the 13.8kV Calvert 1E-NAN-A03 Bus and Insulation"

4OA5.2 Structures Monitoring Frequency and Scope Correspondence Letter 102-06194, "Responses to April 28, 2010, Request for Additional Information (RAI) and Follow-up RAIs, for the Review of the PVNGS [Palo Verde Nuclear Generating Station] License Renewal Application, and License Renewal Application Amendment No. 15," dated May 21, 2010

Letter 102-06160, "Response to March 2, 2010, Request for Additional Information Regarding Settlement, Tendons, Liner, Water Structures, for the Review of the PVNGS License Renewal Application, and License Renewal Application Amendment No. 13," dated April 1, 2010

Attachment Letter 102-06134, "Responses to December 29, 2009, Request for Additional Information Regarding the Aging Management Program (AMP) Audit for the Review of the PVNGS License Renewal Application, and License Renewal Application Amendment No. 9," dated February 19, 2010

Condition Report

Disposition Requests

3439969

3439970

3441953

Miscellaneous

ACI [American Concrete Institute] 349.3R-96, "Evaluation of Existing Nuclear Safety-Related Concrete Structures"

ASTM C 33, "Standard Specification for Concrete Aggregates," Figure 1, "Location of Weathering Regions"

NUREG-1801, "Generic Aging Lessons Learned (GALL) Report - Tabulation of Results," Volume 2, Revision 1

Procedure

81DP-0ZZ01, "Civil System, Structure, and Component Monitoring Program," Revision 16