ML20203L298
| ML20203L298 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 02/13/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20203L297 | List: |
| References | |
| NUDOCS 9803050438 | |
| Download: ML20203L298 (3) | |
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UNITED STATES l
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NUCLEAR REGULATORY COMMISSION i
g WASHINGTON, D.C. 301 6 4001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.121 TO FACILITY OPERATING LICENSE NO. DPR-80 AND AMENDMENT NO.119 TO FACILITY OPERATING LICENSE NO. DPR 82 PACIFIC GAS AND ELECTRIC COMPANY DIABLO CANYON NUCLEAR POWER PLANT. UNITS 1 AND 2 DOCKET NOS. 50 275 AND 50 323
1.0 INTRODUCTION
By application dated May 14,1997, as supplemented by letter dated December 15,1997, Pacific Gas and Electric Company (or the licensee) requested changes to the Technical Specifications (Appendix A to Facility Operating License Nos. OPR 80 and DPR 82) for the Diablo Canyon Nuclear Power Plant, Units 1 and 2. The proposed changes revise the combined Technical Specifications (TS) for the Diablo Canyon Power Plant (DCPP) Unit Nos.1 and 2 to revise TS 6.9.1.8.b.5 to replace reference WCAP 10266 P A with WCAP 12945 P for best estimate loss of coolant accideM (LOCA) analysis. The amendment would also revise TS Bases 3/4.2.2 and 3/4.2.3 to change the emergency core cooling system (ECCS) acceptance criteria limit to state that there is a high level of probability that the ECCS acceptance criteria limits are not exceeded. This is consistent with the best estimate LOCA methodology.
Pacific Gas and Electric Company (PG&E) requested approval to reference the Westinghouse (W) generic best estimate (BE)large break (LB) loss-of coolant accident (LOCA) analysis eveluation model (EM), described in WCAP 12945, June 1996, (approved on June 28,1996) in licensing documentation for Diablo Canyon Units 1 and 2 (Diablo Canyon), and apply that methodology to the Diablo Canyon licensing analyses. WCAP 12945 was originally submitted in September 1992 and underwent several model revisions prior to its approval. WCAP 12945, June 1996, as approved, described a model revision designated as MOD 7A, Revision 1.
The December 15,1997, supplemenal letter provided additional clarifying information and did not change the initial no significant hazards consideration determination published in the Federal Reaister on July 30,1997 (62 FR 40855).
2.0 EVALUATION in its review, the NRC considered the acceptability of the W BE LBLOCA EM described in WCI P 12945, June 1996, for reference in Diablo Canyon licensing documentation and use in Diablo Canyon licensing LBLOCA analyses.
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2-PG&E requested approval to reference the W BE LBLOCA EM described in WCAP 12945, June 1996, in licensing documentation for its Diablo Canyon plants. In its safety evaluation report of June 28,1996, the NRC concluded that this methodology meets the requirements of 10 CFR 50.46, and the NRC found that W BE LBLOCA EM as described in WCAP 12945, June 1996, !s acceptable for use in 3 and 4 loop Westinghouse design licensing applications, including reference in plant technical specifications and core operating limits reports (COLRs).
Diablo Canyon Units 1 and 2 are of 4 loop Westinghouse design with no significant differences from the designs for which the methodology was approved. Inerefore, the staff finds that the W BE LBLOCA EM described in WCAP 12945, June 1996,is acceptable for use in Diablo Canyon licensing applications, including reference in the Diablo Canyon Technical Specification 6.9.1.8.b.5. Inclusion of this methodology in the TS will provide assurance that values for cycle-specific parameters are determined such that all applicable ECCS limits of the safety analysis are met. From its review, the staff concludes that W BE LBLOCA EM, described in WCAP-12945, June 1996, is acceptable for use in Diablo Canyon, Units 1 and 2 licensing applications, including reference in the Diablo Canyon technical specifications and COLR, as approved in the staff evaluation published June 28,1996 (letter from R. C. Jones [U.S. NRC) to N. J. Liparulo (W),
- Acceptance for Referencing of the Topical Report WCAP 12945(P)' Westinghouse Code Qualification Document for Best Estimate Loss of Coolant Analysis'."
The scope of the review documented in this safety evaluation is limited to the use of W BE LBLOCA EM described in WCAP 12945, June 1996, for analyses of LBLOCA scenarios from the time of event initiation to the time of stable core quench. Other uses of this methodology, such as long term (post quench) cooling (e.g., during ECCS switchover) analyses, are beyond the scope of this evaluation. Use of the EM for these and other applications outside the scope of this report must be separately reviewed.
Diablo Canyon in their submittal also proposed revising the Bases for the ECCS acceptance criteria limit to state that there is a high probability that the ECCS acceptance critena limits are not exceeded. This is consistent with the wording in 10 CFR 50.46 and is therefore acceptable to the NRC.
3.0 S' TATE CONSULTATION in accordance with the Commission's regulations, the Califomia State official was notified of the proposed issuance of the amendments. The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
These amendments change a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment'on such finding
V' 3-(62 FR 40855). The change also modifies a recordkeeping or reporting requirement.
Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9) and (c)(10). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
5.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common oefense and security or to the health and safety of the public.
Principal Contributors: F. Orr S. Bloom Date: February 13, 1998 l
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