ML20040H272

Safety Evaluation of Util Response to IE Bulletin 80-06, ESF Reset Controls. Complete Verification Testing of Sys Prior to Restart from Next Refueling Outage for Each Unit Satisfies IE Bulletin 80-06 Concerns

ML20040H272
Person / Time
Site:	Hatch
Issue date:	01/26/1982
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20040H270	List: ML20040H269 ML20040H272
References
IEB-80-06, IEB-80-6, TAC-42746, TAC-42747, NUDOCS 8202180029
Download: ML20040H272 (3)

Text

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• SAFETY EVALU/.TIO" REPORT E. I. HATCH NUCLEAR POWER PLAtlT, UNITS 1 APID 2 LICENSEE RESPONSE TO IEE BULLETIN 80-06, ENGINEERED SAFETY FEATURES (ESF) RESET CONTROLS INTRODUCTION Instances have been reported at operatirig nuclear power plants where it had been found that following the reset of an ESF actuated signal, certain equipment (e.g., ventilation dampers, motors, and valves) would return to its normal mode, which could corpromise the protective actions of the af-fected systems. As a result, on t' arch 13, 1980, the NRC issued IAE Bulletin 80-06 requesting certain actions to be taken by licensees-for all PWR and BWR facilities with operating licenses.

EVALUATION Our evaluation is partically based on a report, (EGG 1183-4201), prepared for us by EG&G, Inc., San Ramon, California. It provides their technical evaluation of the licensee's response to I&E Bulletin 80-06 in accordance with NRC-provided guidance.

EG&G reported the licensee's conclusion that all safety-related equipment remains in its emergency mode upon reset of the ESF actuating signals with two exceptions: (1) the autcmatic depressurization system (ADS) valves and l

(2) the hydrogen and oxygen analyzer system (H0AS) containment isolation valves. The licensee offered justifications in lieu of modifications-to this equipment.

EGAG did not evaluate these justifications.

The licensee cormitted to complete verification testing on the systems reviewed by the 8202180029 820126 PDR ADOCK 05000321 0

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~ end of each unit's refueling outage; the expected completion dates for testing were February 1981, for Unit 2 and June 1981, for Unit 1.

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fore, EG&G found that the plant satisfies the requirements of ISE Bulletin 80-06, with the exception of the ADS and H0AS systems.

Reset of the ADS places it in a standby mode, ready to be initiated as required, rather than in the emergency mode as suggested in the Bulletin. We have reviewed the licensee's justification for not modifying the ADS valves to reset in the emergency mode, and find it acceptable on the basis that the ADS system is actuated under specific conditions, at a time of low reactor coolant inventory, and has been analyzed for blowdown rate and loss of reactor coolant inventory.

Implementing manual resetting of each individual ADS valve

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would have an adverse effect on the blow down rate and the total loss of reactor coolant inventory.

We find the licensee's justification for not modifying the H0AS containment isolation valves acceptable on the basis that the system is designed to the same pressure and temperature ratings as the primary containment and per-forms the singular function of monitoring H and 0 concentrations 2

2 irrediately after an accident.

The reset of the ESF actuation signal reopens the primary containment isolation valves for the HOAS system to meet the design intent of the system.

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3-CONCLUSION Based on the information and documents provided by the licensee, and on our review of the contractor's report, we conclude that the licensee has satis-fled the concerns of I&E Bulletin 80-06, subject to verification by I&E of the successful test completion. Therefore, we conclude that the ESF reset controls for the E. I. Hatch Nuclear Power Plant, Units 1 and 2, are in compliance with applicable NRC criteria.

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