ML17332A481
| ML17332A481 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 12/14/1994 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17332A482 | List: |
| References | |
| NUDOCS 9412280393 | |
| Download: ML17332A481 (2) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 2055&0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULA ION RELATED TO REVISION OF TECHNICAL SPECIFICATION BASES ON FIRE SUPPRESSION SYSTEM
- 1. 0 INTRODUCTION By letters dated March 16, and July 26, 1994, the Indiana Michigan Power Company (the licensee) requested a revision to the Bases of the Donald C.
Cook Nuclear Plant, Unit Nos.
1 and 2 Technical Specifications (TS).
The proposed revision would delete reference to the screenhouse fire pumps as a backup water source for the fire suppression system.
The licensee has proposed, as an alternative, the use of the Lake Township water supply as a backup fire water source.
Although the use of the screenhouse fire pumps as a backup water source is not specified in the body of the TS and only referenced in the
- Bases, use of the pumps was noted as a supportive function in the NRC Safety Evaluation (SE) associated with Amendment Nos.
171 and 154 to the D. C.
Cook TS.
Amendment Nos.
171 and 154 added new TS requirements to reflect the installation of new fire water storage tanks, fire water pumps, and associated components and controls.
- 2. 0 EVALUATION The SE for Cook Amendments 171 and 154 stated that the existing fire suppression water supply system (screenhouse fire pumps) will remain intact.
The system will be isolated to preclude zebra mussel infestation and the automatic controls will be removed.
However, only simple manual action will be required to start and line up these pumps for service.
The SE considered the availability of this backup system as partial justification for allowing a 30-day allowed outage time for one of the newly installed fire water storage tanks.
Although the 30-day allowed outage time was an extension of the typical outage time at the time of the amendment, the improved "Standard Technical Specifications Mestinghouse Plants",
NUREG-1431, issued September
- 1992, removed the fire protection requirements from the TS in their entirety.
The licensee has stated that the use of the Lake Township water supply coupled with the fire suppression capability of the plant and local fire department in lieu of the screenhouse fire pumps does not involve a significant increase in the probability or consequences of an accident previously evaluated, does not create the possibility of a new or different kind of accident from any accident previously evaluated, and does not involve a significant reduction in a margin of safety.
The use of the Lake Township water supply is consistent with and meets the intent of the action statement for TS 3.7.9. 1(b)(2) which requires "Establish[ing]
a backup fire suppression water system within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />."
The Lake Township water supply was found to be capable of refilling a fire water storage tank within the recommended 8-hour period, as 94i2280393 94i2i4 PDR ADOCK 050003i5 P
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were the screenhouse fire pumps.
In addition, the Lake Township water supply can provide a sufficient quantity of water to meet the largest TS fire suppression system demand.
Finally, the licensee has concluded that continued attempts to maintain the screenhouse fire pumps are impractical considering their inherent susceptibility to zebra mussel contamination.
- 3. 0 CONCLUSION Based on the operational difficulties associated with the existing screenhouse fire pumps and the acceptable design alternative of the Lake Township water supply and the fire suppression capability of the plant and local fire department, the staff finds the licensee's proposal to switch the backup fire water source and the deletion of the reference to the screenhouse fire pumps from the Bases to be acceptable.
Principal Contributor:
John B. Hickman, NRR Date:
December 14, 1994