ML062490236
| ML062490236 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 09/12/2006 |
| From: | Kalyanam N NRC/NRR/ADRO/DORL/LPLIV |
| To: | Rosenblum R Southern California Edison Co |
| Kalyanam N, NRR/DORL, 415-1480 | |
| References | |
| TAC MD2469 | |
| Download: ML062490236 (5) | |
Text
September 12, 2006 Mr. Richard M. Rosenblum Senior Vice President and Chief Nuclear Officer Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92674-0128
SUBJECT:
SAN ONOFRE NUCLEAR GENERATING STATION, UNIT 3 - REQUEST FOR ADDITIONAL INFORMATION ON RELIEF REQUEST ISI-3-24, USE OF STRUCTURAL WELD OVERLAY AND ASSOCIATED ALTERNATIVE REPAIR TECHNIQUES (TAC NO. MD2469)
Dear Mr. Rosenblum:
By letter dated June 30, 2006, Southern California Edison submitted a request to use alternatives to the requirements of the American Society of Mechanical Engineers Code,Section XI, 1995 Edition through 1996 Addenda, IWA-4000, for repair/replacement activities related to the performance of structural weld overlays at San Onofre Nuclear Generating Station, Unit 3 for the third 10-year inservice inspection (ISI) interval.
After reviewing your request, the U.S. Nuclear Regulatory Commission staff has determined that additional information is required to complete the review. We discussed this with your staff by telephone on September 5, 2006, and they agreed to provide the additional information requested in the enclosure within 30 days from the receipt of the formal request for additional information.
If you have any questions, please contact me at (301) 415-1480.
Sincerely,
/RA/
N. Kalyanam, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-362
Enclosure:
Request for Additional Information cc w/encl: See next page
September 12, 2006 Mr. Richard M. Rosenblum Senior Vice President and Chief Nuclear Officer Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92674-0128
SUBJECT:
SAN ONOFRE NUCLEAR GENERATING STATION, UNIT 3 - REQUEST FOR ADDITIONAL INFORMATION ON RELIEF REQUEST ISI-3-24, USE OF STRUCTURAL WELD OVERLAY AND ASSOCIATED ALTERNATIVE REPAIR TECHNIQUES (TAC NO. MD2469)
Dear Mr. Rosenblum:
By letter dated June 30, 2006, Southern California Edison submitted a request to use alternatives to the requirements of the American Society of Mechanical Engineers Code,Section XI, 1995 Edition through 1996 Addenda, IWA-4000, for repair/replacement activities related to the performance of structural weld overlays at San Onofre Nuclear Generating Station, Unit 3 for the third 10-year inservice inspection (ISI) interval.
After reviewing your request, the U.S. Nuclear Regulatory Commission staff has determined that additional information is required to complete the review. We discussed this with your staff by telephone on September 5, 2006, and they agreed to provide the additional information requested in the enclosure within 30 days from the receipt of the formal request for additional information.
If you have any questions, please contact me at (301) 415-1480.
Sincerely,
/RA/
N. Kalyanam, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-362
Enclosure:
Request for Additional Information cc w/encl: See next page DISTRIBUTION PUBLIC LPLIV r/f RidsNrrDorlLpl4 RidsNrrPMNKalyanam RidsNrrLALFeizollahi RidsNrrDciCfeb RidsAcrsAcnwMailCenter RidsOgcRp RidsRgn4MailCenter (TPruett)
RidsNrrDorlDpr TSteingass, DCI/CFEB RidsNrrPMBSingal ACCESSION NO: ML062490236
- No major changes from Staff provided RAI OFFICE NRR/LPL4/PM NRR/LPL4/LA NRR/DRA/APLA NRR/LPL4/BC NAME NKalyanam LFeizollahi KGruss
- DTerao DATE 9/11/06 9/11/06 8/1/06 9/12/06 OFFICIAL RECORD COPY
REQUEST FOR ADDITIONAL INFORMATION (RAI)
SAN ONOFRE NUCLEAR GENERATING STATION, UNIT 3 SOUTHERN CALIFORNIA EDISON DOCKET NO. 50-362 RELIEF REQUEST ISI-3-24 TAC NO. MD2469 1.
In your submittal dated June 30, 2006, you state in Section 4.0 that structural weld overlays are proposed for the welds listed. You also state that the thickness of the overlay determined by the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code),Section XI requirement that no flaw of depth greater than 75% through-wall is acceptable, along with the consideration of applied loading.
Since there is no mention in your submittal whether you are doing full-structural overlays, please clarify whether full-structural overlays are to be performed and that no design/optimized overlays will be implemented.
- 2.
Please indicate what types of nondestructive examinations (NDEs) will be performed prior to the weld overlay installation. If pre-welding NDEs are not to be performed, expand your justification for not performing the NDE prior to welding your overlays.
3.
Please discuss your repair strategy as a result of pre-welding NDE. The cover letter indicates that full-structural overlays will be performed as a preemptive application. If a flaw is detected in the weld by NDE prior to a weld overlay, confirm that the weld overlay thickness calculation is based on the worst case flaw.
- 4.
Please identify when the flaw evaluations and shrinkage stress effects analyses required under Code Case N-504-2(g), Items 2 and 3, will be performed as they relate to your outage schedule. It is the staffs expectation that this requirement will be satisfied prior to placing the welds/plant into service. This expectation is reflected in recent safety evaluations since your Relief Request ISI-2-18, dated February 22, 2006. If you cannot complete these analyses prior to startup, relief from this requirement must be requested with sufficient justification for the staff to grant relief.
- 5.
Please indicate the maximum surface area of the part of the overlay that is deposited on the ferritic portions of the weld to confirm whether the 100 square inches limitation of Code Case N-638-1 is met.
- 6.
On page 1 to Table 3 of your submittal, you state: In lieu of the required ultrasonic examination of 4.0(b) only the required liquid penetrant will be performed. The ultrasonic examination will be in accordance with N-504-2 and Appendix Q. You state that... it is believed that for this type of repair that any major base material cracking would take place in the HAZ [heat-affected zone] directly below the weld overlay or in the underlying Inconel 82/182 weld deposit and not in the required band of material out beyond the overlay. Therefore, it is assumed that if this cracking were to occur it would be identified by the ultrasonic examination of the weld overlay and not performing the required base material ultrasonic examination should be considered acceptable. Your statements it is believed and it is assumed do not meet the staffs threshold for an acceptable technical justification in accordance with paragraph 50.55a(a)(3)(i) of Title 10 of the Code of Federal Regulations.
Typically, in lieu of providing an acceptable justification, licensees have requested relief from the ultrasonic area requirements and performed a best effort examination of the 1.5T area. Please provide an acceptable technical justification or revise your relief accordingly.
February 2006 San Onofre Nuclear Generating Station Units 2 and 3 cc:
Mr. Daniel P. Breig Southern California Edison Company San Onofre Nuclear Generating Station P. O. Box 128 San Clemente, CA 92674-0128 Mr. Douglas K. Porter, Esquire Southern California Edison Company 2244 Walnut Grove Avenue Rosemead, CA 91770 Mr. David Spath, Chief Division of Drinking Water and Environmental Management P. O. Box 942732 Sacramento, CA 94234-7320 Chairman, Board of Supervisors County of San Diego 1600 Pacific Highway, Room 335 San Diego, CA 92101 Mark L. Parsons Deputy City Attorney City of Riverside 3900 Main Street Riverside, CA 92522 Mr. Gary L. Nolff Assistant Director - Resources City of Riverside 3900 Main Street Riverside, CA 92522 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 Mr. Michael Olson San Diego Gas & Electric Company P.O. Box 1831 San Diego, CA 92112-4150 Mr. Ed Bailey, Chief Radiologic Health Branch State Department of Health Services Post Office Box 997414 (MS7610)
Sacramento, CA 95899-7414 Resident Inspector/San Onofre NPS c/o U.S. Nuclear Regulatory Commission Post Office Box 4329 San Clemente, CA 92674 Mayor City of San Clemente 100 Avenida Presidio San Clemente, CA 92672 Mr. James T. Reilly Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92674-0128 Mr. James D. Boyd, Commissioner California Energy Commission 1516 Ninth Street (MS 31)
Sacramento, CA 95814 Mr. Ray Waldo, Vice President Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92764-0128 Mr. Brian Katz Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92764-0128 Mr. Steve Hsu Department of Health Services Radiologic Health Branch MS 7610, P.O. Box 997414 Sacramento, CA 95899 Mr. A. Edward Scherer Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92674-0128