ML20003F068
| ML20003F068 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 04/03/1981 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20003F065 | List: |
| References | |
| NUDOCS 8104200083 | |
| Download: ML20003F068 (2) | |
Text
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UNITED STATES nuc'saa neou'aToav co==issio" WASMNGTON O. C. 20555 N..v...f i
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 51 TO FACILITY OPERATING LICENSE NO. OPR-25 CONNONWEALTH EDISON COMPANY d
DRESDEN NUCLEAR POWER STATION, UNIT NO. 3 DCCXET NO. 50-249 Introduction By letter dated April 1,1981, supplemented by letter dated April 3,1981 Comonwealth Edison Comcany (licensee) identified the need to remove three spec 1fic snubbers from the HPCI stea,a line to restore the piping to stress conditions lower than the IE3 79-14 operability limit.
Discussion and Evaluation Recent evaluations of piping in accordance with IE Bulletin 79-14 at Dresden Unit 2 indicate that high local stresses exist at welded lug attachments of some safety related snubbers on the HPCI system. Similar (but not identical) attachments exist on the Dresden Unit 3 HPCI system.
It was therefore decided to perfarn a similar analysis on safety related snubbers on Dresden Unit 3.
As a result of this analysis, it has been found that three snubber locations have stresses higher than FSAR allowable and in excess of the operability limits in IES 79-14. The licensee has evaluated the analysis results and has determined that a higher level of safety can be achieved by removal of j
the snubbers at the overstressed locations. Having made this determination, l
the licensee will, in accordance with Technical Specification, shutdown the l
Unit and perform the modification.
t The snubbers that require removal are components of a safety related system and are listed as nos.18,19 and 20 in Table 3.6.1 of the Technical Speci-fications, Safety Related Shock Suooressors. The licensee thus proposes to remove snubbers 18,19 and 20 from Tadle 3.6.1 for reasons already discussed, to conform the Technical Specification to the new modification.
We concur with the licensee's determination that the modification is desirable to restore applicable limits and thus achieve added safety, and find that the proposed action is acceptable.
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I 2-Environmental Consideration We have determined that the amendment does not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact. Having made this detennination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental impact and pursuant to 10 CFR Section 51.5(;dl(.4) that an environmental impact statement or negative declaration and environmental impact appraisal need not be prepared in connection widi the issuance of this amendment.
Conclusion
'de have concluded, hased on tne considerations discussed above, that:
(1) because the amendment does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the amendment does not involve a significant hazards consideration, (2) there is reasonable assur-ance that the health and safety of the public will not be endangered by oceration in the procesed manner, and (3) such activities will be conducted in compliance with the Ccmmission's regulations and the issuance of the amend-ment will not Se inimical to the common defense and security or to the health and safety of the public.
l Dated:
April 3,1981
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