ML20044G056
| ML20044G056 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 05/20/1993 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20044G051 | List: |
| References | |
| NUDOCS 9306010370 | |
| Download: ML20044G056 (3) | |
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NUCLEAR REGULATORY COMMISSION l
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NOS. 139 AND 143 TO I
FACILITY OPERATING LILENSE N05. DPR-24 AND DPR-27 WISCONSIN ELECTRIC POWER COMPANY' f
POINT BEACH NUCLEAR PLANT. UNIT NOS. 1 AND 2 DOCKET NOS. 50-266 AND 50-301
1.0 INTRODUCTION
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By letter dated June 1,1990 Wisconsin Electric Power Company applied for i
amendments to Facility Operating Licenses DPR-24 and DPR-27 to change the Technical Specifications for the-Point Beach Nuclear P1 ant.
The proposed j
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amendments would change Technical Specification 15.3.3, " Emergency Core l
Cooling System, Auxiliary Cooling Systems, Air Recirculation Fan Coolers, and Containment Spray." Specifically Section 15.3.3. A.2.a. would be revised to l
i allow one accumulator to be isolated-to perform a check valve leakage test or j
be otherwise incperable for a period of up to I hour.
The current technical i
specification reads: "One accumulator may be isolated for a period of up to one hour to permit a check valve leakage test." The proposed amendments would i
change this to read: "One accumulator may be isolated to perform a check valve leakage test or be otherwise inoperable for a period of up to one hour."
The proposed amendments would also revise the corresponding bases section for
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Specification 15.3.3 by adding an example of the application of this limiting condition of operation.
The example that would be added provides insight to the underlying reason for the changes to the limiting condition for operation.
The added wording in the bases would be as follows:
For example, specification 15.3.3. A.2a allows one accumulator to be isolated or otherwise inoperable for periods of up to one hour.
An inoperable accumulator may be defined as one with'its outlet MOV shut, no pressure instrumentation operable, or water and/or nitrogen spaces cross-connected with the accumulator on the other loop.
If the inoperable accumulator is not restored within one hour then the conditions of specification 15.3.0. A and 15.3.0.B apply which requires the affected unit, if critical, to be in hot shutdown within three hours and in cold shutdown within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> if the condition is not corrected.
Finally, the licensee also proposed to make a correction to the bases to Specification 15.3.0.A.
The sentence to be corrected reads: "For example, Specification 15.3.3.A.2.e. permits a single Reactor Coolant System accumu-lator to be isolated for up to one hour during power operations." The correct reference should be to Specification 15.3.3. A.2.a.
This correction is viewed to have no safety significance and is therefore acceptable without further consideration in this safety evaluation.
9306010370 930520 I
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. 2.0 EVALUAILOH The need for the amendments is based on WEPCo's analysis of an event which occurred on July 12, 1989 (Licensee Event Report 89-003-01, dated November 28, 1989). On that date operators were completing a routine level fill of the "B"
safety iniection accumulator. One redundant level indicating instrument ch wael was out of service for maintenance. The level indicating instrument that was in service began giving spurious indications. Operators regained indication by cross connecting the vent and fill lines between the "A" and "B" accumulators. Normal system lineup was restored 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and 49 minutes after the level detector was declared out of service.
I'uring the evaluation of that event WEPCo determined that cross-connecting the accumulators may limit the water available for injecting during a loss of coolant accident (LOCA) resulting from a cold leg break.
According to WEPCo:
"The LOCA analysis for the Point Beach Nuclear Plant assumes that in the event of a cold leg break, the accumulator on the faulted loop injects directly to containment via the pipe break while the accumulator on the non-faulted loop injects to the reactor core.
In the event of a cold leg break with accumulators cross-connected, assuming reactor system pressure prevents injection into the non-faulted loop, water and gas will flow from the accumulator on the non-faulted loop to the accumu-lator on the faulted loop. This limMs the water available for injection into the reactor core from the accumulators. Thus, cross-connecting accumulators results in one accumulator being potentially inoperable and unable to perform its design function in the event of a LOCA resulting from a cold leg break."
Prior to the submittal of this amendment request, WEPCo recognized no constraint on the cross connection of the accumulators to regain level indication. These amendments would add a constraint, limiting the time which the systems could be cross-connected to I hour.
In it, June 1,1990 letter of application, WEPCo noted Technical Specification 15.3.3. A.2.a allows an accumulator to be isolated for up to I hour to perform a check valve leakage test. The accumulator is inoperable while it is isol ated. WEPCo proposed that this I hour limit be made applicable for the accumulator to be inoperable for any reason.
It views this as adding a constraint to the technical specifications.
The standard technical specification (NUREG-1431, SRP 3.5.1) requires that an accumulator be restored to operable status within I hour when it is inoperable for any reason other than boron concentration not within limits. This time limit niinimizes the potential for exposure of the plant to a LOCA when an accumulator is inoperable.
The staff believes that the revision to the bases section defining an inoperable accumulator and specifying corrective actions may be helpful to the j
operators. The staff notes that the standard technical specification would l
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include in the definition of operable that the isolation valve be opened and that power be removed from the isolation valve.
Furthermore, water volume and nitrogen cover pressure should be within design limits.
Because the amendments add an important restriction to the technical specifications and because the limiting condition for operation is consistent with the standard technical specification, the staff finds that the amendments j
improve safety and are acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Wisconsin State official was notified of the proposed issuance of the amendments. The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
These amendments involve a change in the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 or change an inspection or surveillance requirement. The staff has determined j
that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released j
offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. - The Commission has previously published a proposed finding that these amendments involve no significant hazards consideration and there has been no public comment on such finding (56 FR 43819). Accordingly, these amendments meet the eligibility criteria l
for categorical exclusion set forth in 10 CFR 551.22(c)(9).
Pursuant to 10 i
CFR SI.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of these amendments.
5.0 CONCLUSION
l The staff has concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
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Principal Contributor:
R.B. Samworth Date: May 20,1993 l
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