ML19352B117
| ML19352B117 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 05/20/1981 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19352B115 | List: |
| References | |
| NUDOCS 8106030131 | |
| Download: ML19352B117 (3) | |
Text
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UNITED STATES h
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NUCLEAR REGULATORY COMMISSION
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.C WASHINGTON. D. C 20555
%,~....j SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDHENT NO. 56 TO FACILITY OPERATING LICENSE NO. DPR-51 ARKANSAS POWER AND LIGHT COMPANY ARKANSAS NUCLEAR ONE, UNIT NO. 1 DOCKET NO. 50-313 Introduction 3y letter dated October 31, 1980, supplemented by letter dated January 30, 1981, Arkansas _ Power and Light Company (the licensee or AP&L) requested amendment to Facility Operating License No. DPR-51 for Arkansas Nuclear One, linit No.1, which would change the Technical Specifications (TSs) with respect to reactor decay heat removal capability.
Background
By letter dated June 11, 1980, the NRC requested all licensees of a
pressurized water reactors (PWR's) to propose TS changes which would p qvide for redundancy in the decay heat removal capability for their plants. This request was founded on a number of events which occurred at operating PWR's where decay heat removal capability had been seriously degraded due to inadequate administrative controls which would ensure that proper means were available to provide redundant methods of decay heat removal.
In IE Bulletin 80-12 dated May 9,1980, the licensee also was requested to immediately implement administrative controls which would ensure that proper means are available to provide -edundant methods of heat removal. Our request contained Model TSs which would provide for the permanent long term assurance that redundancy in decay heat removal capability would be maintained.
Evaluation The ANO-1 current TSs provide for only one r~eactor coolidt pump or one decay heat removal pump to be in operation whenever boron concentration is being reduced. This is to provide mixing which will prevent sudden positive reactivity changes by dilute coolant reaching the reactor.
However, this is not adequate for single failure considerations whenever the reactor is in the standby mode, is being cooled down to the decay heat removal mode, is in the decay heat removal mode, or is in the refueling mode.
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. The licensee's proposed TSs would require at least one reactor coolant loop with at least one reactor coolant pump in operation and the other reactor coolant loop with at least one reactor coolant pump in standby whenever the reactor coolant temperature is above 280*F. Whenever the reactor coolant system is below 280"F but above the refueling shutdown condition (the decay heat removal mode of operation), the proposed TSs would require at least one reactor coolant loop or one decay heat removal loop in operation and another reactor coolant loop or decay heat removal loop in standby. Whenever the reactor is in the refueling mode of operation, the proposed TSs would require at least one decay heat removal loop be in operation. Whenever the reactor is in the refueling mode of operation with the water level below 23 feet above the core, the proposed TSs would also require the other decay heat removal loop to te in standby.
The proposed TSs woilld provide limiting conditions for operation in the event specified cooling loops were not. operable. The proposed TSs would provide for surveillance requirements to assure the operability of the decay heat removal system and reactor coolant loops as needed for decay hect removal.
We have reviewed the licensee's proposed TSs and find that they provide for redundancy in the methods of heat removal during standby, cooldown and refueling operations and that they are consistent with the Model TSs which we provided in our request dated' June 11, 1980. Therefore, we find the proposed TSs relating to the reactor decay heat removal capability to be acceptable.
We have also discussed with the licensee's staff an existing TS related to the handling of a fuel cask during the cycle three operation which was incorrectly presented with the proposed TSs. Stace this TS was applied on a one-time basis and is no leger applicable, the licensee has agreed to have it deleted from the TSs.
We have determined that the licensee's proposed TSs, as modified, would provide for the permanent long term assurance that decay heat removal capability would be maintained. We find that the licensee's proposed change, as modified, would not decrease the margin of safety or increase the probability or consequences of an accident and therefore find the proposed change as modified acceptable.
Environmental Consideration We have detemined 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 determination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental impact and, pursuant to 10 CFR 551.5(d)(4), that an environmental impact J
statement, or negative declaration and environmental impact appraisal need not be prepared in connection with the issuance of this amendment.
. Conclusion We have concluded, based on the 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 assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will 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.
Dated: May 20, 1981
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