ML20054E100
| ML20054E100 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 04/14/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20054E095 | List: |
| References | |
| NUDOCS 8204260136 | |
| Download: ML20054E100 (2) | |
Text
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9'o UNITED STATES 8
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NUCLEAR REGULATORY COMMISSION 5
.. 1 WASHINGTON, D. C. 20555 V
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 70 TO PROVISIONAL OPERATING LICNESE NO. 20
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CONSUMERS POWER COMPANY l
PALISADES NUCLEAR PLANT DOCKET NO. 50-255
1.0 INTRODUCTION
By.a letter dated May 5, 1980, Consumers Power Company (the licensee) proposed changes to the Technical Specifications (TSs) appended to Provisional Operating License No. DPR-20 for the Palisades Nuclear Plant. The change clarifies the implementation of the TSs with regard-to shutdown margin requirements with less than four primary coolant pumps in operation.
2.0 BACKGROUND
The Palisades Technical Specifications, Section 3.1.1.c, allows the plant to be operated with less than four primary coolant pumps (PCPs) running. However, Section 3.10.1.b, as it presently exists, will be violated if this is done before the 3.75% shutdown margin is obtained.
The proposed Technical Specification change to Section 3.10.1.b will allow the operator to operate the plant with less than four PCPs running' while increasing the SDM to e3.75%.
3.0 EVALUATION As part of t.he application for operation at power leve.ls up to 2530 MWt (Amendment 31, November 1, 1977) the steam line break accident was reanalyzed for two loop (four pump) operation at both full power and zero power conditions. Both analyses assumed a shutdown margin of
-2.0% 4. For the 102% power case a MDNBR of 1.30 and p'eak power of 464 MWt were predicted.
For the zero power case a MDNBR of 1.41 and peak power of 693 MWt were predicted.
The steam,line break accident was also analyzed for less than four operating primary coolant pumps (PCPs) since limited operation (12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />) is authorized at partial power following the trip of one or two PCPs. The most severe case was determined to be for 1 loop operation at zero power conditions. The two active pumps were assumed to be located in the ruptured loop. The analysis was performed to determine the required shutdown margin to just prevent return to power even though some return to power would be allowed for this accident.
It was shown that a shut-down marg'in of 3.75% ap would be required.
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2-In the event that a PCP needs to be shutdown (high vibration,. seal leak, etc), the shutdown margin (SDM) will be less than the required 3.75%,.
even while taking the SDM of the control rods into account. However, if the operator waits to shut down the PCP until the SDM is increas~ed to 3.75%, approximately 30 minutes, the PCP would be severely damaged or the plant operated in an unsafe condition. Therefore, since it is highly improbable that a major accident as described above would occur in the ensuing 30 minutes required to borate, we conclude that the pro-posed change is acceptable.
4.0 ENVIRONMENTAL CONSIDERATION
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We have determined 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 statement, or negative declaration and environ-mental impact appraisal need not be prepared in connection with the issuance of the amendment.
5.0 CONCLUSION
We have concluded, based on the considerations discussed above, that:
(1) because the amendment does not involve a significant increase in
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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 publi.c 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.
Date:
April 14,1982 9
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