PNO-I-87-116, on 871215,motor-operated Outboard Drywell Spray Discharge Isolation Valve RHR-26A Failed to Stoke & Valve Overload Alarm Received & Valve Breader Tripped.Standby Diesel Generator B Being Restored

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PNO-I-87-116:on 871215,motor-operated Outboard Drywell Spray Discharge Isolation Valve RHR-26A Failed to Stoke & Valve Overload Alarm Received & Valve Breader Tripped.Standby Diesel Generator B Being Restored
ML20237C197
Person / Time
Site: Vermont Yankee Entergy icon.png
Issue date: 12/15/1987
From: Grant G, Haverkamp D, Wiggins J
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
References
PNO-I-87-116, NUDOCS 8712210123
Download: ML20237C197 (1)


m. ,-

o y DCS No: 50271871215 i-Date: December 15, 1987 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-I-87116

(

This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The information is as initially received without i verification or evaluation, and is basically all that is known by the Region .I i

staff on this date.

hcility: Licensee Emergency Classiff cation:

Vermont Yankee Nuclear Power Corp. X Notification of Unusual Event Vermont Yankee Nuclear Power Plant Alert Vernon, Vermont Site Area Emergency )

General Emergency __ l l Docket No. 50-271 Not Applicable  ;

Subject:

LOSS OF SAFETY FUNCTION OR ENGINEERED SAFETY FEATURE WHICH REQUIRES A PLANT SHUTDOWN On December 15, 1987 at 12:30 a.m., the B standby diesel generator was removed from  ;

service to perform preventive maintenance not accomplished during the 1987 refueling outage. Alternate testing of the operable A standby diesel generator and train A and .

B low pressure core and containment cooling systems was commenced at 1:11 a.m. in  !

accordance with TS 3.4.H.1 requirements. At 4:12 a.m. the motor operated outboard drywell spray dist.harge isolation valve RHR-26A failed to stroke and a valve overload

. alarm was received and the valve breaker tripped. The valve was declared inoperable '

and a reactor shutdowa was initiated in accordance with TS 3.5.H.1 which requires that an orderly Outdown be initiated and the reactor be in cold shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> if alternate test;ng criteria are not met.

An unusual even; was declared as of 4:21 a.m. in accordance with facility emergency action levels. The NRC Operations Center and the appropriate local and state notifications were made. As of 10:00 a.m., the reacter was at 95% of rated power and the licensee was restoring the B standby diesel generator to an operable condition and replacing the failed valve motor operator.

The resident inspector is onsite reviewing the licensee s actions.

This PN is issued for information only. The States of Vermont, Massachusetts and New '

Hampshire have been notified. Media interest is anticipated regarding this matter.

CONTACT: D. Haverkamp (488-1120) J. Wiggins (488-1224) G. Grant (802) 257-4319 1

j 8712210123 971215 ,0 DCD N-1 -116 0 f },

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