ML16342A738
| ML16342A738 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 03/23/1999 |
| From: | Steven Bloom NRC (Affiliation Not Assigned) |
| To: | Rueger G PACIFIC GAS & ELECTRIC CO. |
| Shared Package | |
| ML16342A739 | List: |
| References | |
| GL-95-05, GL-95-5, TAC-MA2387, NUDOCS 9903290156 | |
| Download: ML16342A738 (4) | |
Text
March 23, 1999 I
1 Mr. Gregory M. Rueger Senior Vice President and General Manager Pacific Gas and Electric Company Diablo Canyon Nuclear Power Plant P. O. Box 3 Avila Beach California 93424 I
SUBJECT:
REVIEW OF DIABLOCANYON UNIT2 REFUELING OUTAGE 8 (END OF CYCLE 8) STEAM GENERATOR INSPECTION 90-DAY REPORT (TAC No.
MA2387)
Dear Mr. Rueger:
By letter dated June 26, 1998, Pacific Gas and Electric Company (the licensee) submitted its steam generator (SG) 90-day report, "90-Day Report for Voltage-Based Alternate Repair Criteria - Unit 2 Eighth Refueling Outage." The report,was submitted in accordance with Generic Letter (GL) 95-05, "Voltage-Based Repair Criteria for Westinghouse Steam Generator Tubes Affected by Outside Diameter Stress Corrosion Cracking," as a result of implementing the voltage-based alternate repair criteria in the Diablo Canyon Unit 2 technical specifications (TS).
The amendment approving the use of voltage-based repair criteria for Diablo Canyon Unit 2 included a reporting threshold of 1 x 10'or the conditional probability of tube burst. The licensee estimated a conditional burst probability below this threshold using an NRC staff approved methodology.
The estimates of the primary-to-secondary leak rate during a postulated main steam line break (MSLB) for Diablo Canyon Unit 2 were below the 12.8 gpm value assumed in the licensing basis accident analyses and were determined using an NRC staff approved methodology.
We conclude that the licensee implemented the voltage-based repair criteria in accordance with its licensing basis.
The staff's review is contained in the enclosed safety evaluation.
Sincerely, Original Signed By Steven D. Bloom, Project Manager Project Directorate IV-2 Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-323
Enclosure:
Safety Evaluation cc w/encl: See next page OFC PDIV-2 PDIV-2 DISTRIBUTION:
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Mr. Gregory M. Rueger Parch 23, 1999 cc w/encl:
NRC Resident Inspector Diablo Canyon Nuclear Power Plant c/o U.S. Nuclear Regulatory Commission P. O. Box 369 Avila Beach, California 93424 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission Harris Tower 8 Pavillion 611 Ryan Plaza Drive, Suite 400 Arlington, Texas 76011-8064 Dr. Richard Ferguson, Energy Chair Sierra Club California 1100 11th Street, Suite 311 Sacramento, California 95814 Christopher J. Warner, Esq.
Pacific Gas & Electric Company Post Office Box 7442 San Francisco, California 94120 Ms. Nancy Culver San Luis Obispo Mothers for Peace P. O. Box 164 Pismo Beach, California 93448 Chairman San Luis Obispo County Board of Supervisors Room 370 County Government Center San Luis Obispo, California 93408 Mr. David H. Oatley, Vice President Diablo Canyon Operations and Plant Manager Diablo Canyon Nuclear Power Plant P.O. Box 3 Avila Beach, California 93424 Telegram-Tribune ATTN: Managing Editor 1321 Johnson Avenue P.O. Box 112 San Luis Obispo, California 93406
.Mr. Truman Burns A
Mr. Robert Kinosian California Public Utilities Commission 505 Van Ness, Room 4102 San Francisco, California 94102 Mr. Steve Hsu Radiologic Health Branch State Department of Health Services Post Office Box 942732 Sacramento, California 94232 Diablo Canyon Independent Safety Committee ATTN: Robert R. Wellington, Esq.
Legal Counsel 857 Cass Street, Suite D Monterey, California 93940
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