ML16342C008
| ML16342C008 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 09/02/1993 |
| From: | Peterson S Office of Nuclear Reactor Regulation |
| To: | Rueger G PACIFIC GAS & ELECTRIC CO. |
| Shared Package | |
| ML16342A235 | List: |
| References | |
| TAC-M86229, TAC-M86230, NUDOCS 9309140380 | |
| Download: ML16342C008 (6) | |
Text
Dock'et Nos. 50-275 and 50-323 Hr. Gregory H. Rueger Nuclear Power Generation,
B 1 4A Pacific Gas and Electric Company 77 Beal e Street,
Room 1 45 1 P. 0.
Box 7 70000 San Francisco, California 941 77
Dear Hr. Rueger :
September 2, 199
SUBJECT:
SAFETY EVALUATION OF INDICATIONS IN THE SAFETY INJECTION ACCUMULATOR TANKS FOR DIABLO CANYON NUCLEAR POWER
- PLANT, UNIT NO.
1 (TAC NO. H86229)
AND UNIT NO.
2 (TAC'NO. M86230)
By letters dated April 19 and 28, and August 2, 1993, Pacific Gas and Electric Company (PG&E) submitted descriptions of the disposition of accumulator cladding indications found during the fifth refueling outage for Diablo Canyon Unit 2.
The indications were located in the stainless steel cladding of 'the steel accumulator tanks and extended up to, but not into, the base metal.
These surface flaws exceeded the acceptance criteria'f the ASHE Code,Section XI and required analysis.
The licensee did a fracture mechanics evaluation using the flaw acceptance criteria of Section XI and the analytical
'procedures of Appendix A of the Code.
The evaluation showed that the flaws were acceptable without grinding or repair.
The evaluation also addressed corrosion as a possible cause of degradation.
The licensee stated that such degradation would be negligible.
Our preliminary evaluation has completed its in-depth dispositioned according to evaluation (Enclosure 1).
was forwarded to you on April 22, 1993.
The staff review and concludes that the flaws were properly the ASHE Code.
Enclosed is the staff safety This closes TAC Nos.
H86229 and H86230.
Sincerely, Original signed by:
Sheri R. Peterson, Project Manager Project Directorate V
Division of Reactor Projects III/IV/V Office of Nuclear Reactor Regulation
Enclosure:
Safety Evaluation cc w/enclosure:
See next page DISTRIBUTION:
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UNITEDSTATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 September 2,
1993 Docket Nos.
50-275 and 50-323 Hr. Gregory H. Rueger Nuclear Power Generation, B14A Pacific Gas and Electric Company 77 Beale Street, Room 1451 P.O.
Box 770000 San Francisco, Cali forni a 94177
Dear Hr. Rueger:
SUBJECT:
SAFETY EVALUATION OF INDICATIONS IN THE SAFETY INJECTION ACCUHULATOR TANKS FOR DIABLO CANYON NUCLEAR POWER PLANT, UNIT NO.
1 (TAC NO. H86229)
AND UNIT NO.
2 (TAC NO. H86230)
By letters dated April 19 and 28, and August 2, 1993, Pacific Gas and Electric Company (PGIlE) submitted descriptions of the disposition of accumulator cladding indications found during the fifth refueling outage for Diablo Canyon Unit 2.
The indications were located in the stainless steel cladding of the steel accumulator tanks and extended up to, but not into, the base metal.
These surface flaws exceeded the acceptance criteria of the ASHE Code,Section XI and required analysis.
The licensee did a fracture mechanics evaluation using the flaw acceptance criteria of Section XI and the analytical procedures of Appendix A of the Code.
The evaluation showed that the flaws were acceptable without grinding or repair.,
The evaluation also addressed corrosion as a possible cause of degradation.
The licensee stated that such degradation would be negligible.
Our preliminary evaluation has completed its in-depth dispositioned according to evaluation (Enclosure 1).
Enclosure:
Safety Evaluation cc w/enclosure:
See next page was forwarded to you on April 22, 1993.
The staff review and concludes that the flaws were properly the ASHE Code.
Enclosed is the staff safety This closes TAC Nos.
H86229 and H86230.
Sincerely, Sheri R. Peterson, Project Hanager Project Directorate V
Division of Reactor Projects III/IV/V Office of Nuclear Reactor Regulation
Mr. Gregory M. Rueger Pacific Gas and Electric Company Diablo Canyon CC:
NRC Resident Inspector Diablo Canyon Nuclear Power Plant c/o U.S. Nuclear Regulatory Commission P. 0.
Box 369 Avila Beach, California 93424 Dr. Richard Ferguson, Energy Chair Sierra Club California 6715 Rocky Canyon
- Creston, California 93432 Ms. Nancy Culver San Luis Obispo Mothers for Peace P. 0.
Box 164 Pismo Beach, California 93448 Ms. Jacquelyn C. Wheeler 3303 Barranca Court San Luis Obispo, California 93401 Managing Editor The County Telegram Tribune 1321 Johnson Avenue P. 0.
Box 112 San Luis Obispo, California 93406 Chairman San Luis Obispo County Board of Supervisors Room 370 County Government Center San Luis Obispo, California 93408 Mr. Truman Burns Mr. Robert Kinosian California Public Utilities Commission 505 Van Ness, Rm.
4102 San Francisco, California 94102 Mr. Steve Hsu Radiologic Health Branch State Department of Health Services Post Office Box 942732 Sacramento, California 94234 Regional Administrator, Region V
U.S. Nuclear Regulatory Commission 1450 Maria Lane, Suite 210 Walnut Creek, California 94596 Mr. Peter H. Kaufman Deputy Attorney General State of California 110 West A Street, Suite 700 San Diego, California 92101 Christopher J.
- Warner, Esq.
Pacific Gas
- 5. Electric Company Post Office Box 7442 San Francisco, California 94120 Mr. John Townsend Vice President and Plant Manager Diablo Canyon.Power Plant P. 0.
Box 56 Avila Beach, California 93424 Diablo Canyon Independent Safety Committee ATTN:
Robert R. Wellington, Esq.
Legal Counsel 857 Cass Street, Suite D
Monterey, California 93940
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