ML20238D692
| ML20238D692 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 12/30/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20238D688 | List: |
| References | |
| NUDOCS 8801040366 | |
| Download: ML20238D692 (3) | |
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uco UNITED STATES e
[
g NUCLEAR REGULATORY COMMISSION
<l WASHINGTON, D. C. 20555 g.....e SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.102 TO FACILITY OPERATING LICENSt: NO. DPR-28 VERMONT YANKEE NUCLEAR POWER CORPORATION VERMONT YANKEE NUCLEAR POWER STATION DOCKET NO. 50-271
1.0 INTRODUCTION
By letter dated January 16, 1987 from W.P. Murphy to H.R. Denton, Vermont Yankee Nuclear Power Corporation (the licensee) requested changes to the Technical Specifications for Vermont Yankee Nuclear Power Station (VYNPS).
The changes are intended to clarify the existing specifications for the Standby Liouid Control System (SLCS) through a more explicit statement of flow, relief valve, circuitry, and triager assembly operability test requirements.
2.0 EVALUATIO'N As a result of problems identified during the 1986 SLCS surveillance test, wherein both redundant components of the SLCS were inoperable in that their explosive squib valves would not actuate, if required, to provide a flow path from the Standby Liquid Control System storage tank to the reactor vessel; the licensee initiated several corrective actions, including a review of the Technical Specifications pertaining to specific requirements concerning testing / surveillance of the SLCS.
In a May 22, 1986 letter to the NRC Region I Administrator, the licensee described, as follows, corrective actions taken to enhance the reliability of the SLCS:
"When purchasing new charges, we will specifically request a copy of the corresponding drawing.
This drawing will be compared against the copy on file at the plant.
Specifically, the reviewer will look for any changes that may exist between the new drawings and the file drawings; accuracy; traceability to the purchase order; and traceability to the assemblies to be used.
If this review is satisfactory, three (3) new assemblies, all manufactured from the same batch, will be removed from Stores after confirming they will not exceed their shelf life during the next cycle and tested for pin-to-pin continuity. At this point, in accordance with Vermont Yankee's surveillance procedure requirements, 8801040366 871230 DR ADOCK 050 1
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. I operability of SLC System is demonstrated, in part by demonstrating detonation of both installed trigger assemblies. Subsequently, one of-the three new assemblies is installed in the firing circuit and test fired to demonstrate acceptability of the batch. The remaining two new assemblies are then installed in the SLC Squib valves to render the system operable for the next operating cycle."
~In the May 22, 1986 letter, the licensee also committed to propose appropriate technical changes concerning the SLCS testing and surveillance requirements consistent with the above program.
The YY Technical Specification Limiting Condition for Operation (LCO) 3.4.A requires the SLCS to be operable whenever fuel is in the reactor and the reactor ode switch is not in the shutdown position.
Technical Specification LCO 3.4.6 permits operation to continue in the existing mode for seven days j
if a reaundant component of the SLCS is inoperable.
Unless Technical
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Specification LCOs 3.4.A or 3.4.B are met, the reactor shall be in the cold shutdown condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
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i The proposed change reformats Sections 3.4.A, 4.4.A, 3.4.C, and 4.4.C to I
clarify SLC operability and surveillance requirements.
Further, the Section i
4.4. surveillance requirement'is revised to specify flow, relief valve, circuitry, and trigger assembly operability functional test surveillance requirements.' In addition to the above, the Section 3.4 and 4.4. Bases Section is revised to specify the SLC System operability functional testing-requirements.
The staff has reviewed the Technical Specification changes proposed by the licensee. The changes do not involve any modification to the SLCS system performance requirements, design basis, or setpoints.
The changes constitute an enhancement of the wording of the existing specifications, and a clarification as to which tests are specifically required to demonstrate SLCS operability.
The Technical Specification changes proposed by the licensee constitute an improvement to the wording of the existing specifications without any relaxation of current requirements. As a result, we have concluded that they are acceptable.
3.0 ENVIRONMENTAL CONSIDERATION
S 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 amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that.may
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1 1 i 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 amendment involves no significant hazards consideration and there has been no public comment on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth I
Pursuant to 10 CFR 51.22(b), no environmental impact I
statement or environmental assessment need be prepared in connect' ion with the issuance of the amendment.
4.0 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 b7 endangered by operation in the proposed manne:, and (2) such activities will J
be conducted in compliance with the Commission's regulations, and the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
l Principal Contributor:
T. Collins and V. Rooney 1
Dated: December 30, 1987 l
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