ML18093A164

Special Rept 87-4:on 870527,shift Noticed Increase of Approx 0.25 Gpm in Containment Sump Leak Rate.Caused by Leaking Gasket in Containment Fan Coil Unit Lower Cooler End Bell. Bolts on Lower Cooler End Bell Retorqued & Leakage Stopped

ML18093A164
Person / Time
Site:	Salem
Issue date:	06/08/1987
From:	Zupko J Public Service Enterprise Group
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
87-4, NUDOCS 8706160412
Download: ML18093A164 (3)

Text

- *~.-. *':.... .. ~ .

e OPS~G Public Service Electric and Gas Company P.O. Box E Hancocks Bridge, New Jersey 08038 Salem Generating Station June 8, 1987

u. S. Nuclear Regulato~y Commission Document Control Desk Washington, DC 20555

Dear Sir:

SALEM GENERATING STATION LICENSE NO. DPR-70 DOCKET NO. 50-272 UNIT NO. 1 REPORT 87-4 SPECIAL REPORT This Special Report describes the circumstances* surrounding a Service Water leak inside the containment. This report is being submitted within fourteen days of the occurrence in accordance with the reporting requirements of I.E. Bulletin 80-24.

Sincerely yours,

~µ9-J. M. Zupko, Jr.

General Manager-Salem Operations RKH:pc Distribution

~6R6160412 e7o60a

• S ADOCK 05000272 PDR The Energy People 95-2189 (11 MJ 12-84

e SPECIAL REPORT NUMBER 87-4 PLANT IDENTIFICATION:

Salem Generating Station - Unit 1 Public Service Electric & Gas Company Hancock's Bridge, New Jersey 08038 IDENTIFICATION OF OCCURRENCE:

SERVICE WATER LEAK INSIDE CONTAINMENT - NO. 11 CONTAINMENT FAN COIL UNIT LOWER COOLER LEAK DUE TO LOOSE BOLTS ON THE END BELL Event Date(s): 05/27/87 Report Date: 06/08/87 This report was initiated by Incident Report No.87-201 CONDITIONS PRIOR TO OCCURRENCE:

Mode 1 - Rx Power 100% - Unit Load 1152MWe DESCRIPTION OF OCCURRENCE:

On May 27, 1987, during routine power operation, the shift noticed an increase of. approximately .25 gpm in the containment sump leak rate.*

Subsequent performance of a Reactor Coolant System (RCS) Inventory did not indicate a leak from the Chemical Volume and Control System (CVCS} or the RCS. Therefore, a containment entry was performed and it was discovered that No. 11 Containment Fan Coil Unit (CFCU) had developed a leak in the lower cooler end bell gasket. The CFCU was isolated and Technical Specification Action 3.6.2.3.a was entered at 1606 hours0.0186 days <br />0.446 hours <br />0.00266 weeks <br />6.11083e-4 months <br />.- The NRC was notified at 1627 hours0.0188 days <br />0.452 hours <br />0.00269 weeks <br />6.190735e-4 months <br /> the same day.

Subsequently, on May 28, 1987, at 1950 hours0.0226 days <br />0.542 hours <br />0.00322 weeks <br />7.41975e-4 months <br />, No. 11 CFCU was restoted to operable status and Action Statement 3.6.2.3.a was terminated.

APPARENT CAUSE OF OCCURRENCE:

Upon investigation, the CFCU lower cooler end bell was found to have a leaking gasket. The bolts on the end bell were retorqued and the leakage stopped. No other leaking gaskets were discovered.

ANALYSIS OF OCCURRENCE:

An increase in containment sump inleakage is the primary indication of the development of RCS or other system leakage. Continuous monitoring of the sump inleakage allows early detection of a potential problem and provides a basis for initiation of appropriate actions to identify, isolate, and repair the leak.

Performance of an RCS water inventory. balance in conjunction with a containment entry to locate the source of the inleakage is the appropriate action.

• ' e UNIT.1 SPECIAL REPORT 87-4 ,, I ANALYSIS OF OCCURRENCE: (cont'd)

The unavailability of one CFCU does not significantly affect the ability to provide containment cooling. During normal operation there are one or more idle CFCUs, depending on containment temperature. During an accident condition, the remaining CFCUs are able to provide adequate redundancy to the Containment Spray System for cooling and depressurizing the containment.

As demonstrated by this occurrence, minor leakage can be detected through monitoring and observing a change in containment sump level increase and following the established administrative controls.

Leakage can also be detected via sampling.

Due to the small size of this leak (.25 gpm), had it remained undetected during a LOCA, it would have had negligible immediate impact on boron concentration, chloride contamination, and pH levels. Over the long term (post LOCA), the inleakage would be detected through RCS sampling, allowing selected isolation of the leaking CFCU. These concerns are adequately addressed by the current plant design and administrative controls in effect.

Based upon the above analysis, this occurrence involved no undue risk to the health and safety of the public. Additionally, no equipment damage resulted from the service water leak. However, all service water leaks inside containment are reportable in accordance with I.E.

Bulletin No. 80-24.

CORRECTIVE ACTION:

The bolts on the lower cooler end bell were retorqued and the leakage stopped. Gasketed joints for the other containment fan coil units were inspected with no further action required.

RKH:pc SORC Mtg.87-040