05000311/LER-1982-080, Forwards LER 82-080/01T-0.Detailed Event Analysis Encl

Forwards LER 82-080/01T-0.Detailed Event Analysis Encl

ML20063M991
Person / Time
Site:	Salem
Issue date:	09/03/1982
From:	Midura H Public Service Enterprise Group
To:	Haynes J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20063M992	List: 05000311/LER-1982-080, Forwards LER 82-080/01T-0.Detailed Event Analysis Encl
References
NUDOCS 8209160530
Download: ML20063M991 (4)

LER-1982-080, Forwards LER 82-080/01T-0.Detailed Event Analysis Encl

Event date:
Report date:
3111982080R00 - NRC Website

text

inPSEG Public Service Electric and Gas Company P.O. Box E Hancocks Bridge, New Jersey 08038 Salem Generating Station September 3, 1982 Mr.

R.

C.

Haynes Regional Administrator USNRC Region 1 631 Park Avenue King of Prussia, Pennsylvania 19406

Dear Mr. Haynes:

LICENSE NO. DPR-75 DOCKET NO. 50-311 REPORTABLE OCCURRENCE 82-080/0lT Pursuant to the requirements of Salem Generating Station Unit No.

2, Technical Specifications, Section 6.9.1.8.c, we are submitting Licensee Event Report for Reportable Occurrence 82-080/0lT.

This report is required within fourteen (14) days of the occurrence.

Sincerely yours, l l.

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H.

J. Midura General Manager -

Salem Operations i

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Distribution i

8209160530 820903 F'

PDR ADOCK 05000311 S

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Report Number:

82-080/OlT Report Date:

09-03-82 Occurrence Date:

08-21-82 Facility:

Salem Generating Station, Unit 2 Public Service Electric & Gas Company Hancocks Bridge, New Jersey 08038 IDENTIFICATION OF OCCURRENCE:

Containment Service Mater Leak - No. 24 Containment Fan Coil Unit.

This report was initiated by Incident Reports82-227 and 82-228.

CONDITIONS PRIOR TO OCCURRENCE:

Mode 1 - Rx Power 82% - Unit Load 900 MWe.

DESCRIPTION OF OCCURRENCE:

At 0508 hours0.00588 days <br />0.141 hours <br />8.399471e-4 weeks <br />1.93294e-4 months <br />, August 21, 1982, during routine operation, the Control Room Operator noticed an increase of leakage to the containment sump as determined by operation of the sump pump.

Since the unidentified leakage was greater than 1 GPM, Technical Specification Action Statement 3.4.7.2.b was entered for unidentified Reactor Coolant System (RCS) leakage.

A containment entry was made to identify the leakage, and at 0850 hours0.00984 days <br />0.236 hours <br />0.00141 weeks <br />3.23425e-4 months <br />, a 1.0 GPM service water leak was observed emanating from the cooling coils on No. 24 Containment Fan Coil Unit (CFCU).

Service water to the CFCU was isolated, and the unit was declared inoperable.

No. 25 CFCU had been inoperable since August 19, 1982, and Action Statement 3.6.2.3.b was entered.

In accordance with NRC IE Bulletin 80-24, the NRC was notified by telephone, with written confirmation transmitted on August 23, 1982.

With un-identified leakage less than 1 GPM, Action Statement 3.4.7.2.b was terminated at 0850 hours0.00984 days <br />0.236 hours <br />0.00141 weeks <br />3.23425e-4 months <br />.

The containment spray systems were both operable throughout the occurrence.

DESIGNATION OF APPARENT CAUSE OF OCCURRENCE:

The leakage was due to the failure of the CFCU cooling coils.

The coils are fabricated from copper-nickel alloy which is susceptible to erosion by the silt laden service water.

Similar failures of other CFCU's have been noted, with most leaks occurring at bends where erosion is more significant.

Corrosion involving dissimilar metals in the service water piping may also be involved.

l

LER 82-080/0lT...

ANALYSIS OF OCCURRENCE:

Primary containment is a design feature which ensures that the release of radioactive materials in the event of accident conditions will be restricted such that site boundary radiation doses will be within the limits of 10CFR100.

NRC IE Bulletin 80-24 requires that any service water leak inside the containment be considered as a degradation of the containment boundary.

If containment pressure increased to the design pressure of 47 psig during an accident, there is a possibility of the release of radioactivity through the service water discharge.

The occurrence, therefore, constituted an abnormal degradation of the primary containment and is reportable in accordance with Technical Specification 6.9.1.8.c.

The RCS leakage limits are based on ensuring the ability of detecting leakage from the Reactor Coolant Pressure boundary.

The boundary is one of the several design features which prevent the release of radioactive fission products to the environment (the others are the fuel cladding and primary containment).

Action Statement 3.4.6.2.'b requires:

with any pressure boundary leakage, be in at least hot standby within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />; with any RCS leakage greater than any one of the Technical Specification limits, excluding pressure boundary leakage, reduce the leakage rate to within limits within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, or be in at least hot standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

The CFCU's operate in conjunction with the containment spray systems to remove heat and radioactive contamination from the containment atmosphere in the event of a design basis accident.

Operability of either all fan coil groups or of both containment spray systems is necessary to ensure offsite radiation dose is maintained within the limits of 10CFR100.

Action Statement l

3.6.2.3.b requires:

with two groups of containment cooling fans inoperable, restore at least one group of cooling fans to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, or be in at least hot standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

Because the leakage was immediately isolated, containment integrity was maintained.

Containment cooling capability was provided by the containment spray systems.

The occurrence, therefore, involved no risk to'the health or safety of the public.

Due to the loss of redundancy in design and engineered safety features, the event constituted operation in a degraded mode permitted by the limiting conditions for operation.

LER 82-080/0lT...

CORRECTIVE ACTION

As noted, the leakage was immediately isolated, and prompt notification performed in accordance with Technical Specification 6.9.1.8,c.

The unidentified leakage was determined to be less than 1.0 GPM and Action Statement 3.4.7.2.b was terminated within the specified interval.

The leaky cooler was repaired with Belzona metal filler and leakage was stopped.

The CFCU was re-turned to operation and satisfactorily tested.

At 2043 hours0.0236 days <br />0.568 hours <br />0.00338 weeks <br />7.773615e-4 months <br />, August 21, 1982, the unit was declared operable, and Action State-ment 3.6.2.3.b was terminated.

Design Change Request 2EC-0505 has been issued to replace the CFCU cooling coils with coils manufactured of AL-6X steel, for improved erosion and corrosion resistance in the service water environment.

This change is scheduled for implementation during the next refueling outage.

A commitment to submit a Supplemental Report upon completion was made in LER 82-070/0lT.

FAILURE DATA:

A number of containment service water leaks due to similar failures of CFCU cooling coils have occurred since January 1, 1982.

Westinghouse Electric Corporation Containment Fan Coil Unit U-Tube Cooling Coil Prepared By R.

Frahm

/, h M

Gen (ral Manager -

Salem Operations SORC Meeting No.

82-80 l

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