ML20196D698
| ML20196D698 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 12/06/1988 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20196D694 | List: |
| References | |
| TAC-69038, NUDOCS 8812090166 | |
| Download: ML20196D698 (2) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON.D C 20044
- 't, SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION
[EL ATED TO AMENDHENT NO.135 E
TO FACILITY OPERATING LICENSE NO. OPR-65 NORTHEAST NUCLEAR ENERGY COMPANY ET AL.
MILLSTONE NUCLEAR POWER STATION, UNIT NO. 2 DOCKET NO. 50-336 INTRODUCTION By application for license asendment dated August 2, 1988, Northeast Nuclear Energy Company, et al. (the licensee), requested a change to Technical Specification (TS) 4.7.8.c "Snubbers," for Millstone Unit 2.
The proposed change to the TS would decrease the sample size, for subsequent tests of snubbers, from 10% to 5% of the snubber test population.
DISCUSSION AND EVALUATION Technical Specification 4.7.8.c requires that the licensee periodically, functionally, test 10% of each type of seismic sway arrestor (snubber).
For each snubber or a particular type (hydraulic, mechanical, design or vendor specific) that fails the initial test, a subsequent test of 10% of the snubber test population would also be required.
The testing would continue until all snubbers in the test pupulation have been tested or until no additional failures have been detected. The licensee has proposed that the subsequent test population, following snubber test failure, be decreased from 101 to 51 of the test popublation.
The licensee's recent experience with snubbers at Millstone Unit 2 has shown this equipinent to be reliable. Following a 1001 overhaul / test of snubbers during the 1985 refueling outage, the following was noted:
1 During the 1986 refueling outage, one hydraulic snubber failed to pass toe functional test. Subsequent testing revealed no additional failuies.
For mechanical snubbers, one failure was detected with one additional failure during subsequent testing.
Ouring the 1987 refueling outage, there were no snubber test failures.
8812090166 8s1206 ADOCK0500g6 DR
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9 2-A 5% follow-up sample size has been previously authorized for Millstone Unit 1.
Justification for this change was based on statistics showing that a 5% follow-l up sample for each failure provides essentially the same confidence level as the first 10% sample. Whereas, the 10% follow-up samples, for each failure, continually improves the confidence level above that obtained with the first Jample. The statistical conclusions reached, concerning the Unit 1 snubber i
follow-up sample are equally applicable to the Unit 2 snubber follow-up l
sample. Accordingly, the proposed change to Millstone Unit 2 TS 4.7.8.c.
which reduces the required follow-up snubber test sample from 10% to 5%, is acceptable.
ENVIRONMENTAL CONSIDERATION This amendment changes surveillance requirements. The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, o' any effluents that may be released offsite, i
and that there is no significant increase in individual or cumulative occupational radiation exposure. The Comission has previously published a proposed finding that the amendmnt involves no significant hazards 2
consideration and there has been no public conrent on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 561.22(c)(9). Pursuant to 10 CFR 551.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
CONCLUSION I
Wehaveconcluded,basedontheconsiderationsdiscussedabove,that(1)there is reasonable assurance that the health and safety of the public will not be endangeredbyoperationintheproposedmanner,and(2)suchactivitieswillbe conducted in compliance with the Comission's regulations, and the issuance of the amendnent will not be inimical to the connon defense and security or to the health and safety of the public.
Dated:
Dece:nber 6,1988 Principal Contributor:
D. Jaffe
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