ML20063K734
| ML20063K734 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 02/16/1994 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20063K733 | List: |
| References | |
| NUDOCS 9403020064 | |
| Download: ML20063K734 (2) | |
Text
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pa a'%g f-UNITED STATES
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NUCLEAR REGULATORY COMMISSION
'g WASHINGTON, D.C. 20555-0001
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...s SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 67 TO FACILITY OPERATING LICENSE NO. NpF-39 PHILADELPHIA ELECTRIC COMPANY LIMERICK GENERATING STATION. UNIT 1 DOCKET NO. 50-352
1.0 INTRODUCTION
By letter dated Novmeber 30, 1993, Philadelphia Electric Company submitted a request for changes to the Limerick Generating Station (LGS), Unit 1, Technical Specifications (TS).
The requested changes would allow a one-time extension of the third Type A Containment Integrated Leakage Rate Test (CILRT), by approximately 15 months in the first 10-year service period.
2.0 EVALUATION The existing TS 4.6.1.2.a. states that three Type A tests (Overall Integrated Containment Leakage Rate) shall be conducted at 40 10-month intervals during shutdown at P, (44 psig) during each 10-year service period.
The 50-month maximum interval for the third Type A test within the first 10-year service period would be extended to approximately 65 months.
This extension will prevent performing four CILRTs, one more than required, within the first 10-year service period.
The benefit of not performing the additional CILRT is a reduction in personnel radiation exposure. A dose saving will be realized from eliminating contamination, reducing exposure for venting and draining, and from setup and restoration of instrumentation required to perform the test.
Data from the pre-operational (August 1984), first (August 1987) and second (November 1990) CILRT, at LGS, Unit 1, indicates that most of the measured leakage is from the containment penetrations and not from the containment barrier. The "as-left" leakage rates were well below the 10 CFR Part 50 Appendix J limit. Both Appendix J and the TS require that the leakage rate be less that 75% of L to allow for deterioration in leakage paths between tests.
Theallowableleakagerate,L is 0.5 wt.%/ day.
Therefore, the established acceptable limit is < 0.37,i wt.%/ day.
The "as-left" leakage rates for the pre-operational and first two JILRTs were 0.225%, 0.178% and 0.334%
wt.%/ day, which are below the acceptance limit.
The Type B and C test (Local Leakage Rate Test or LLRT) program also provides assurance that containment integrity has been maintained. LLRTs demonstrate operability of components and penetrations by measuring penetration and valve leakage. Additionally, there have been no modifications made to the plant that could adversely affect the test results.
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The only failure of tha CILRT occurred during the August 1987 test.
During this CILRT, the leakage rate was 1.0 wt.%/ day. The licensee determined that the excessive leakage was caused by packing gland leaks on nine containment atmosphere control (CAC) system valves. This failure was caused by a maintenance error and was not age related. The configuration of the CAC valves was subsequently modified by the licensee so that the LLRT would identify any packing leaks in the future.
In addition, all containment inboard isolation valves that are located outside containment (i.e., the same configurations as the CAC valves) were reviewed and modified by the licensee to ensure that the packing would be subject to the LLRT pressure.
Since the licensee has justified the leaktight integrity of the containment based on previous leakage test results, the staff concludes that a one-time extension of approximately 15 months beyond the maximum permitted test interval will not have a significant safety impact. The staff, therefore, concludes that the licensee's requested one-time schedular test interval extension for conducting the third CILRT of the first 10-year service period is acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Pennsylvania State official was notified of the proposed issuance of the amendment.
The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a surveillance requirement. The NRC staff has determined that the amendment involves 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
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proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (58 FR 67858). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
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 regalations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
F. Rinaldi Date: February 16, 1994
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