ML080230553
| ML080230553 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 01/11/2008 |
| From: | Mims D Arizona Public Service Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 102-05796-DCM/DLK/RJR, GL-07-001 | |
| Download: ML080230553 (2) | |
Text
Generic Letter 2007-01 Dwight C. Mims Mail Station 7605 Palo Verde Nuclear Vice President Tel. 623-393-5403 P.O. Box 52034 Generating Station Regulatory Affairs and Plant Improvement Fax 623-393-6077 Phoenix, Arizona 85072-2034 102-05796-DCM/DLKIRJR January 11, 2008 Attn: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
Dear Sirs:
Subject:
Palo Verde Nuclear Generating Station (PVNGS)
Units 1, 2, and 3 Docket Nos. STN 50-52815291530 Response to NRC Request for Additional Information on Arizona Public Service's (APS) Response to Generic Letter 2007-01 By letter number 102-05697, dated May 3, 2007, Arizona Public Service Company (APS) submitted the information requested in Generic Letter 2007-01, "Inaccessible or Underground Power Cable Failures That Disable Accident Mitigation Systems or Cause Plant Transients." The Generic Letter specifically requested information relative to inaccessible or underground power cable failures for all cables that were within the scope of 10 CFR 50.65 (the Maintenance Rule) and for all voltage levels.
By letter dated November 8, 2007, the NRC requested additional information on cables associated with cable splice failures referenced in APS's original response to Generic Letter 2007-01. The NRC asked that "if the reworked cables (i.e., cables associated with the degraded splices) were within the scope of the Generic Letter, provide the data requested for each repaired cable requested in GL 2007-01."
APS's original response to the Generic Letter included the following statement:
"In addition, while not directly related to cablefjacket insulation degradation, PVNGS has experienced dielectric strength test failures of degraded cable splices on power cables in manholes. The cable splices were reworked in accordance with the PVNGS corrective action program."
The failures referred to in the statement above were provided as additional information -
outside the scope of Generic Letter 2007-01.
A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway 0 Comanche Peak
- Diablo Canyon
- Palo Verde & South Texas Project
- Wolf Creek 1
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ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Request for Additional Information on APS Response to NRC Generic Letter 2007-01 Page 2 Dielectric strength testing at Palo Verde normally includes testing multiple components at the same time (e.g. motors, terminations, splices, cables, etc.). When test results are unacceptable, the components are isolated so that the cause of the unacceptable test results can be determined. The dielectric strength test failures discussed in the statement above were found using this process. These failures were caused by degraded splices, not degraded cable jacket/insulation (i.e. splice test failures not cable test failures) and the degraded splices were located in accessible manholes. Because the test failures were not attributed to power cable failures and the degraded splices were located in accessible manholes, the failures do not fall within the scope of Generic Letter 2007-01 or the guidance provided to the Nuclear Energy Institute in the NRC letter dated April 13, 2007.
No commitments are being made to the NRC by this letter. If you have any questions, please contact Glenn Michael at (623) 393-5750.
Sincerely, DCM/SAB/DLK/gat cc: E. E. Collins Jr.
NRC Region IV Regional Administrator M. T. Markley NRC NRR Project Manager G. G. Warnick NRC Senior Resident Inspector for PVNGS