05000272/LER-1979-059, Forwards LER 79-059/03L-0

Forwards LER 79-059/03L-0

ML18081B272
Person / Time
Site:	Salem
Issue date:	03/27/1980
From:	Librizzi F Public Service Enterprise Group
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML18081B273	List: 05000272/LER-1979-059, Forwards LER 79-059/03L-0 05000272/LER-1979-059-03, /03L-0:on 790424 & 0508,during Refueling Outage, Public Svc Relay Dept Was Performing Relay Tests & de-energized Vital Bus Supplying Operating RHR Pump.Caused by Inadequate Work Procedures.Low Level Limit Raised
References
NUDOCS 8004010356
Download: ML18081B272 (3)

LER-1979-059, Forwards LER 79-059/03L-0

Event date:
Report date:
2721979059R00 - NRC Website

text

Public Service Electric and Gas Company 80 Park Place Newark, N.J. 07101 Phone 201 i430-7000 March 27, 1980 Mr. Boyce H. Grier Director of USNRC Off ice of Inspection and Enforcement Region 1 631 Park Avenue King of Prussia, Pennsylvania 19406

Dear Mr. Grier:

LICENSE NO. DPR-70 DOCKET NO. 50-272 REPORTABLE OCCURRENCE 79-59/03L Pursuant to the requirements of Salem Generating Station Unit No. 1 Technical Specifications, Section 6.9.1, we are submitting Licensee Event Report for Reportable Occurrence 79-59/03L.

Following a review of 1979 Incident Reports, it was determined, in conjunction with the Resident Inspector, that the enclosed incidents are reportable as Licensee Event Reports.

Sincerely yours, Al,~

F. P. Librizzi General Manager -

Electric Production CC:

Director, Office of Inspection and Enforcement (30 copies)

Director, Office of Management Information and Program Control (3 copies)

Report Number:

79-59/03L Report Date:

3/27/80 Occurrence Date:

April 24, May 8, June 30, 1979 Facility:

Salem Generating Station Public Service Electric & Gas Company Hancock's Bridge, New Jersey 08038 IDENTIFICATION OF OCCURRENCE:

Loss of Residual Heat Removal (RHR) Pump CONDITIONS PRIOR TO OCCURRENCE:

Refueling Mode 6 DESCRIPTION OF OCCURRENCE:

On April 24 and May 8, 1979, during Unit 1 first refueling outage, Relay Department personnel were performing tests on vital bus breakers.

During the testing evolution, the vital bus supplying the operating RHR Pump inadvertently de-energized, causing loss of RHR flow.

In each case, operating personnel were aware of the relay work and alerted to the possibility of loss of the operating RHR Pump.

No core alterations or dilutions were in progress.

RHR flow was restored within two minutes on April 24, 1979, and within four minutes on May 8, 1979.

On June 30, 1979, also during the refueling outage, the operating RHR Pump started to lose suction and was removed from service.

The

.reactor vessel water level was checked at 97 feet 1 inch.

The reactor vessel water level was increased to 97 feet 6 inches and the RHR Pump was returned to service.

RHR flow was lost for 34 minutes.

DESIGNATION OF APPARENT CAUSE OF OCCURRENCE:

The cause of the occurrences on April 24, 1979 and May 8, 1979 was due to improper Relay Department action during the relay testing.

On June 30, 1979, due to maintenance being performed on plant equipment, the reactor vessel water level was lowered to approximately one inch above the low operating level for the RHR Pump.

This incident showed that the low operating level did not provide sufficient suction for the RHR Pump.

ANALYSIS OF OCCURRENCE:

Technical Specification 3.9.8 states, "At least one residual heat removal loop shall be in operation." Action Statement a.requires that "with less than one residual heat removal loop in operation, except as provided in b. below, suspend all operations involving an increase in the reactor decay heat load or a reduction in boron concentration of the Reactor Coolant System.

Close all containment penetrations providing direct access from the containment atmosphere to the outside atmosphere within four hours."

c.-..

LER 79-59/03L 2 -

Action Statement b requires, "The residual heat removal loop may be removed from operation for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> per 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period during the performance of core alterations in the vicinity of the reactor vessel hot legs."

During all three occurrences, no core alteration or reactivity changes were in progress.

The Technical Specification limiting condition for operation was not exceeded as the maximum time RHR flow was lost was 34 minutes.

As a point of interest, Amendment 24 to Salem Technical Specifi-cations 3.4.1.1 in all modes except Refueling Modes, with reactor power below P-7 and with K ff < 1.0, all Reactor Coolant Pumps and Residual Heat Removal Pumps may be de-energized for up to one hour, provided no operations are permitted which could cause dilution of the Reactor Coolant System boron concentration.

CORRECTIVE ACTION

The Relay Department has reviewed and corrected their procedures and operating practices to prevent recurrence of this problem.

An on-the-spot change has been implemented which changes the low reactor water level alarm set point from the centerline of the hot leg pipe (approximately 97 feet) to 97 feet 6 inches.

These occurrences are considered isolated incidents and no further corrective action is required.

FAILURE DATA:

. Not applicable Prepared By A. W. Kapple SORC Meeting No.

'20-80'