ML20055E682
| ML20055E682 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 07/05/1990 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20055E681 | List: |
| References | |
| NUDOCS 9007120235 | |
| Download: ML20055E682 (3) | |
Text
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wun UNITED STATES 9,,
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WASHINGTON, D. C. 20656 r,
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION
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RELATED TO AMENDMENT NOS.129 AND 113 TO FACILITY OPERATING LICENSE N05. NPF-4 AND NPF-7 V,1RGINTA ELECTRIC AND POWER, COMPANY 7
OLD 00MINTON ELECTRIC COOPERATIVE NORTH ANNA POWER STATION, UNITS NO. 1 AND NO. 2 DOCKET N05. 50-338 AND 50-339 l
INTRODUCTION By letter dated March 23, 1990, the Virginia Electric and Power Company (the licensee)proposedchangestotheTechnicalSpecifications(TS)fortheNorth Anna Power Station, Units No. I and No. 2 (NA-1&2).
Specifically, the changes would remove the 3.25 limit on extending surveillance intervals required by TS 4.0.2 for NA-1&2 as recommended by NRC Generic Letter 89-14.
In addition, the changes would extend TS 4.0.3 to allow a 24-hour period to complete a missed surveillance requirement before entering into the applicable action statement in accordance with NRC Generic Letter 87-09.
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DISCUSS 10'd The NA-1&2 TS 4.0.2 permits surveillance intervals to be extended up to 25 percent of the specified interval. This extension facilitates the scheduling of surveillance activities and allows surveillance activities to be postponed when plant conditions are not suitable for conducting the surveillance, for example, under transient conditions or other ongoing surveillance or maintenance activities. TS 4.0.2 also limits extending surveillances so that r
the tombined time interval for any three consecutive surveillance intervals doer, not exceed 3.25 times the specified surveillance interval. The intent of
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5 the 3.25 limit is to preclude routine use of the provision for extending a r
surveillance interval by 25 percent. As currently expressed, this
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specification is consistent with the Standard TS for Westinghouse Pressurized Water Reactors, NUREG-0452, Revision 4.
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On August 21, 1989, the NRC issued Generic Letter (GL) 89-14, which provides guidance to licensees for proposing a license amendment to implement removal of the 3.25 limitation for three consecutive surveillance intervals. As stated in the GL, the NRC considers this to be a line-item improvement to the TS. The revised specification will remove an unnecessary restriction on extending surveillance requirements and will result in a benefit to safety when plant conditions are not conducive to the safe conduct of surveillance requirements.
The removal of the 3.25 limit will provide greater flexibility in the use of the provision for extending surveillance intervals, reduce the administrative
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y burden associated wif.h its use, and have a positive effect on safety.
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' Revised TS 4.0.3 would permit delaying the requirement of an action statement for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to permit the completion of a missed surveillance when the allowable outage time limits of the action statement are less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or require a shutdown. As discussed in GL 87-09, it is overly conservative to assume that systems or components are.immediately inoperable because a surveillance requirement has not been performed. Generally the opposite is in fact the case. The vast majority of surveillances confirm that the tested system or component is within requirements and operable. When a surveillance is missed, it is this positive verification of operability that has not been confirmsd by the performance of the required surveillance. Because the allowable outage " me limits of some action statements do not provide an appropriate time 1 :it for performing a missed surveillance before shutdown requirements may apply, the TS should include a time limit that would allow a delay-of the required actions to permit the performance of the missed surveillance.
This time limit should be based on considerations of plant conditions, adequate planning, availability of personnel, the time required to perform the survei'.-
lance, as well as the safety significance of the delay in completion of the surveillance. GL 87-09 states that, based on these considerations, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is an acceptable time limit for completing a missed surveillance when the allowable outage times of the action statements are less than this time limit or when shutdown action statements apply. The GL concludes that the 24-hour time limit adequately balances the risks associated with potential for a plant upset and challenge to safety systems when the alternative is a shutdown to comply with action statements before the surveillance can be completed.
These proposed TS changes are consistent with the guidance provided in NRC GL 89-14 and NRC GL 87-09. Approval of the change request will produce the
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Facilitate scheduling of surveillance activities and allow surveillances to be postponed when plant conditions are not conducive to the safe conduct of the surveillance.
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Reduce the potential for unnecessary forced shutdowns to perform surveillance activities.
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Eliminate the administrative and logistical burdens associated with tracking the use of the 25 percent allowance to ensure compliance with i
3.25 limit.
I EVALUATION GL 87-09 stated that it is overly conservative to assume that systems or y
components are inoperable when a surveillance requirement has not been performed. Therefore, delay of up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to permit completion of a missed surveillance would be allowed. The GL also states that the 24-hour time limit would balance the risks associated with an allowance for completing l
the surveillance within this period against the risks associated with plant upset and challenge to safety systems when the alternative is shut down.
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'l 3-For the changes intended to achieve consistency with the recomendations of, GL 87-09, " Sections 3.0 and 4.0 of the Standard Technical Specifications on the Applicability of Limiting Conditions for Operation and Surveillance Requirements,"
1 the NRC staff has previously evaluated these changes in the GL and determined that the modifications will result in improved TS.
GL 89-14 states that removal of the 3.25 limitation for three consecutive surveillance intervals will remove an unnecessary restriction on extending surveillance requirements and will result in a benefit to safety when plant conditions are not conducive to the safe conduct of surveillance requirements.
The proposed changes are in accordance with the guidance provided in GLs 87-09
.and 89-14 Therefore, based on all of the above, we find the proposed changes 6
to be acceptable.
Finally, the staff noted an administrative error in the licensee's _ proposed changes to the Bases pages. The change to TS 4.0.3 on page B 3/4 0-3 involved i
additional paragraphs which required the addition of a new page (B 3/4 0-3a).
However, page B 3/4 0-4, which was not included in the licensee's submittal, still contained language from the unchanged TS 4.0.3.
Therefore, for consistency the staff has included page B 3/4 0-4 in these amendments with the incorrect language from TS 4.0.3 deleted.
ENVIRONMENTAL CONSIDERATION r
These amendments involve a change to a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. We have 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 these amendments involve no significant hazards consideration and there has been no public comment on such finding. Accordingly, these amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
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-Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of these amendments.
CONCLUSION We have concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health and safety of the public will not be j
endangered by operation in the proposed manner, and (2) such activities will l
be conducted in compliance with the Commission's regulations, and the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
l Date:
July 5, 1990 Principal Contributor:
L. Engle i