ML20244B433
| ML20244B433 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 06/02/1989 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20244B374 | List: |
| References | |
| NUDOCS 8906130111 | |
| Download: ML20244B433 (2) | |
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UNITED STATES l'
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NUCLEAR REGULATORY COMMISSION N ll,',, ll WASHINGTON, D. C. 70555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT N0.112TO FACILITY OPERATING LICENSE NO. DPR-28 VERMONT YANKEE NUCLEAR POWER CORPORATION VERM0'iT YANKEE NUCLEAP POWER STATION DOCKET NO. 50-271 Introduction By letter dated August 5,1983 and supplemented on Varch 4,1985, the Vermont Yankee Nuclear Power Corporation (Verraont Yankee, the licensee) requested cheoges to facility Operating License No. DPR-28. Clarifying information was provided on May 18, 1989 which did not substantially change the March 4, 1985 letter, therefore a determination was made not to renotice the application.
The changes modify the Technical Specifications to add limiting conditions of operation and surveillance requirements for the reactor protection system (RPS) power protection panels.
2.0 Background
By NRC generic letter dated September 24, 1980, the staff expressed concern regarding the design of RPS monitoring equipment in BWRs, and requested appropriate modifications. By letter dated June 27, 1984 the staff found that the Vermont Yankee plant proposed design modifications addressing these concerns were acceptable, and proposed administratively-controlled interim J
e set points and surveillance requirements were acceptable until f.'nalization h
I and approval of Technical Specifications.
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3.0 Evaluation
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The RPS protection panels were installed to protect the RPS equipment from a postulated seismic failure of the RPS normal power supply (RPS MG sets).
Identical panels were also irstalled on the alternate supply for the RPS.
Undervoltage, overvoltage, and underfrequency setpoints were chosen for the Technical Specifications based on the requirements of the RPS equipment connected to +he RPS busses. Equipment ratings and line voltage drops were taken into account. The time deleys were included in the Technical Specifications for the protection panels to eliminate spurious trips due to transients and noise. The time delays were chosen to allow protection panels to trip before the equipment operating limits are reached, therefore, maximum delay settings were limited by RPS equipment ratings.
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The changes included in this proposal add requirements to the Technical
' Specifications to enhance the reliability of the RPS protection panels. The addition of these changes to the Technical Specifications improves the reliability of the RPS pcwer supplies and enhances the overall safety of the plant, therefore; the staff finds the proposed changes to be acceptable.
4.0 Environmental Consideration j
This amendment involves a change in the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20.
The staff has determined that the amendmer.t involves n? 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 published a proposed finding that the emendment involves no significant hazards
. i consideration and there has been no public comment on such finding. Accordingly, this amendment meets the eligibility criteria for categorical exclusion set l
forthin10CFR51.22(c)(9). Pursuantto10-CFR51.22(b),noenvironmental impact statement or environmental assessment need be prepared in connection l
with the issuance of this amendment.
5.0 Conclusion We have concluded, based on the consideration discussed above, that (1) therts is reasonable assurance that the health safety of the public will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Connission's regulations, and issuance of this amendment will not be inimical to to the common defense and security w to the health and safety of the nublic.
Principal Contributor:
V. Rooney Dated: June 2, 1989 I
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