ML081400526
| ML081400526 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 05/27/2008 |
| From: | Kalyanam N NRC/NRR/ADRO/DORL/LPLIV |
| To: | Rosenblum R Southern California Edison Co |
| Kalyanam N, NRR/DORL/LPL4, 415-1480 | |
| References | |
| TAC MD5953 | |
| Download: ML081400526 (5) | |
Text
May 27, 2008 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 - EVALUATION OF 2006 STEAM GENERATOR TUBE INSERVICE INSPECTION REPORT (TAC NO. MD5953)
Dear Mr. Rosenblum:
By letters dated May 25, and December 26, 2007 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML071520093 and ML073610391, respectively), Southern California Edison (the licensee), submitted information summarizing the results of the 2006 steam generator (SG) tube inspections performed at San Onofre Nuclear Generating Station, Unit 3 (SONGS 3) during the Cycle 14 refueling outage (3C14).
In addition, the U.S. Nuclear Regulatory Commission (NRC) staff summarized additional information concerning the SG tube inspections at SONGS 3 in a letter dated December 18, 2006 (ADAMS Accession No. ML063450313).
The NRC staff completed its review of these reports and concludes that the licensee provided the information required by their technical specifications and that no additional follow-up is required at this time. The NRC staff review of the reports is enclosed.
Sincerely,
/RA/
N. Kalyanam, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-362 cc w/encl: See next page
The NRC staff completed its review of these reports and concludes that the licensee provided the information required by their technical specifications and that no additional follow-up is required at this time. The NRC staff review of the reports is enclosed.
Sincerely,
/RA/
N. Kalyanam, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-362 cc w/encl: See next page DISTRIBUTION:
PUBLIC LPLIV r/f RidsNrrDorlLpl4 RidsNrrPMNKalyanam RidsNrrLAGLappert RidsNrrDciCsgb RidsAcrsAcnwMailCenter RidsOgcRp RidsNrrDorlDpr EMurphy, CSGB RidsRgn4MailCenter KKarwoski, CSGB AJohnson, CSGB ADAMS Accession No.: ML081400526 NRR-106
- Tech Staff Input OFFICE NRR/LPL4/PM NRR/LPL4/LA NRR/DCI/CSGB/BC*
NRR/LPL4/BC NAME NKalyanam:gkl GLappert AHiser THiltz DATE 5/27/08 5/19/08 5/20/08 5/27/08
SUMMARY
OF REVIEW BY THE OFFICE OF NUCLEAR REACTOR REGULATION SAN ONOFRE NUCLEAR GENERATING STATION, UNIT 3 2006 STEAM GENERATOR TUBE INSPECTIONS TAC NO. MD5953 DOCKET NO. 50-362 By letters dated May 25, and December 26, 2007 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML071520093 and ML073610391, respectively), Southern California Edison (the licensee), submitted information summarizing the results of the 2006 steam generator (SG) tube inspections performed at San Onofre Nuclear Generating Station, Unit 3 (SONGS 3) during the Cycle 14 refueling outage (3C14).
In addition, the U.S. Nuclear Regulatory Commission (NRC) staff summarized additional information concerning the SG tube inspections at SONGS 3 in a letter dated December 18, 2006 (ADAMS Accession No. ML063450313).
There are two Combustion Engineering Model 3410 SGs at SONGS Unit 3. Each SG has 9,350 mill-annealed, Alloy 600 tubes. The tubes have an outside diameter of 0.75 inches, and a wall thickness of 0.048 inches. Carbon steel eggcrate tube supports, diagonal straps, and vertical straps support the tubes at various locations. The tubes were expanded through the full depth of the tubesheet using an explosive process.
The licensee provided the scope, extent, methods, and results of their SG tube inspections in the documents referenced above. In addition, the licensee described corrective actions (e.g.,
tube plugging) taken in response to the inspection findings.
After review of the information provided by the licensee, the NRC staff has the following comment/observation:
To ensure the batwings in the stay cavity region were intact, the licensee:
- a.
familiarized their analysts with eddy current data from another plant that had experience batwing damage,
- b.
confirmed that a support was present at all wear scars (a rotating probe inspection was performed at all wear locations) and that there were no non-wear volumetric indications,
- c.
re-analyzed eddy current data focusing on looking for indications of batwing displacement, and
- d.
performed a foreign object search and retrieval (FOSAR) at the top of the tubesheet in which no batwing material was found.
Based on a review of the information provided by the licensee, the staff concludes that the licensee provided the information required by their technical specifications. The SG tube inspections at SONGS Unit 3 appear to be consistent with the objective of detecting potential tube degradation and the inspection results appear to be consistent with industry operating experience at similarly designed and operated units.
San Onofre Nuclear Generating Station (December 2007)
Units 2 and 3 cc:
Douglas K. Porter, Esquire Southern California Edison Company 2244 Walnut Grove Avenue Rosemead, CA 91770 Dr. David Spath, Chief Division of Drinking Water and Environmental Management California Dept. of Health Services 850 Marina Parkway, Bldg P, 2nd Floor Richmond, CA 94804 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 General Manager - Resources Riverside Public Utilities City of Riverside, California 3901 Orange Street Riverside, CA 92501 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 Mr. Michael L. De Marco San Diego Gas & Electric Company 8315 Century Park Ct. CP21G San Diego, CA 92123-1548 Resident Inspector San Onofre Nuclear Generating Station 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 California State Liaison Officer Vice Chair and Commissioner California Energy Commission 1516 Ninth Street, MS 31 Sacramento, CA 95814 Mr. Gary Butner Acting Branch Chief Department of Public Health Services Radiologic Health Branch MS 7610, P.O. Box 997414 Sacramento, CA 95899-7414 Mr. Ross T. Ridenoure Vice President and Site Manager Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92674-0128 Mr. A. Edward Scherer Director, Nuclear Regulatory Affairs Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92674-0128