05000311/LER-1983-013, Forwards LER 83-013/03L-0.Detailed Event Analysis Encl

Forwards LER 83-013/03L-0.Detailed Event Analysis Encl

ML20074A760
Person / Time
Site:	Salem
Issue date:	05/06/1983
From:	Zupko J Public Service Enterprise Group
To:	Allan J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20074A761	List: 05000311/LER-1983-013, Forwards LER 83-013/03L-0.Detailed Event Analysis Encl
References
NUDOCS 8305160052
Download: ML20074A760 (5)

LER-2083-013, Forwards LER 83-013/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
3112083013R00 - NRC Website

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. s O PSEG Public Service Electric and Gas Company P.O. Box E Hancocks Bridge, New Jersey 08038 Salem Generating Station May 6, 1982 Mr. J. Allan Acting Regional Administrator USNRC Region 1 631 Park Avenue King of Prussia, Pennsylvania 19406 Dear Mr. Allan LICENSE NO. DPR-75 DOCKET NO. 50-311 REPORTABLE OCCURRENCE 83-013/03L Pursuant to the requirements of Salem Generating Station Unit No. 2, Technical Specifications, Section 6.9.1.9.b, we are submitting Licensee Event Report for Reportable Occurrence 83-013/03L. This report is required within thirty (30) days of the occurrence.

Sincerely yours, 4f U/l

• j J. M. Zupko, Jr.

General Manager -

Salem Operations RF:kshd[

CC: Distribution 8305160052 830506 PDR ADOCK 05000311 8 PDR The Energy People p-(fr2!h # Cr '! 1181

O Report Number: 83-013/ 03L 1 Report Date: 05-04-83 Occurrence Date: 04-09-83 Facility: Salem Generating Station Unit 2 4

Public Service Electric & Gas Company Hancock's Bridge, New Jersey 08038 IDENTIFICATION OF OCCURRENCE: r Reactivity Control Systems - No. 22 Charging Pump - Inoperable.

This report was initiated'by Incident Report 83-067.

CONDITIONS PRIOR TO OCCURRENCE:

Mode 6 - RX Power 0 % - Unit Load 0 MWe.

DESCRIPTION OF OCCURRENCE:

At 1618 hours0.0187 days <br />0.449 hours <br />0.00268 weeks <br />6.15649e-4 months <br />, April 9, 1983, du' ring routine shutdown operation, an operator observed increasing lube oil temperatures on No. 22 Charging Pump. At the time of the occurrence. the redundant charging pumps were unavailable due to maintenance activities associated with the shutdown. No. 22 Charging Pump was declared inoperable and Technical Specification Action Statement 3.1.2.3 was entered.

Investigation of the problem indicated that service water flow was 1

being restricted to the charging pump as well as several other safety-related components; the components were all supplied by a common 4 inch branch of the No. 21 Service Water Header. Other components affected included No. 21 Containment Spray Pump Room Cooler, No. 22 Charging Pump Room Cooler, No. 21 Safety Injection Pump Lube Oil Cooler, and No. 21 Residual Heat Removal Pump Room Cooler.

Suspecting the flow may be restricted by shells of American oysters released during maintenance and cleaning of portions of the service water system earlier in the shutdown period, a backflush of the affected components was performed. The backflush path was through the 4 Service Water System auxiliary feedwater pump cross-connect line.

Upon opening the cross-connect line, silt was observed deposited in the end of the line; the silt and approximately 1/2 cubic feet of shells of oysters and other miscellaneous mollusks were removed in the process of flushing the line.

All operations involving core alteration and positive reactivity changes were suspended until the backflushing operation was completed j and No. 22 Charging Pump was restored to an operable status.

Several weeks later, on April 21, 1983, investigation of a high jacket water temperature condition on No. 2C Emergency Diesel Generator revealed loose shells in the diesel jacket water and lube oil coolers.

The diesel is also supplied by No. 21 Service Water Header, which had been completely rafilled following the previous flushing evolution.

LER 83-013/03L DESCRIPTION OF OCCURRENCE: (cont'd)-

i No; problems were evident with Nos. 2A and 2B Diesel Generators.

t however, and surveillance'of the generators has been satisfactorily

' completed to date (No. 2A Diesel Generator is normally supplied byDNo.

22 Service Water Header). Only two' operable generators are required by the Technical Specifications during shutdown' operation, and therefore compliance with the applicable limiting condition for operation was maintained.

APPARENT CAUSE OF OCCURRENGE:

In both cases the reduced service water flow was evidently caused by mollusk shells plugging the tubes of the coolers. Both living i organisms and unattached shells were. observed in the backflushes.

Specimens of shells collected were unusually thin, and appeared to have=been subjected to erosion.

1 Although problems with oysters restricting flow to the containment fan-coil units (CFCUs) have been previously noted (see LERs 82-041/03L, 82-046/03L, 82-049/03L, 82-050/03L, 82-058/03L, and 82-117/03L). the i events were random and .relatively low in frequency. No problems with I other safety related components had been observed during previous operation of-the unit. -

As-noted in previous reports, oyster spat were apparently-drawn into e the Service Water System during operation, and were able to pass through the' system strainers. They cemented themselves to piping i walls in areas of moderate or reduced flow and developed . shells. The 4 -oysters or shells-were evidently released somewhat randomly during i . system operational events (pump shif ts, lineup changes, etc.) and

. periodic chlorinations. The top shells of dead organisms would also be carried away following decay of the' hinge.

Due to.the previous problems, the No. 21 Service Water Header had been

' drained'and manually cleaned where accessible. The 8' inch ~ header upstream of all components involved except the. diesels'had been hydrolazed prior to the incident. . Shells had been removed from.the

. header, and reverse flow of the hydrolazing' nozzle would likely have deposited a.small volume of the shells in the 4 inch branch line which

! supplied the components. It was not possible to prevent ~a small amount of shells from entering the line, and it was assumed that the l amount involved would have no significant impact on operating-equipment.

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, According to the Environmental Department and biological consultants, i living oysters removed by hydrolazing would likely survive in an unattached state. Draining of major portions of the header may have resulted: in mortality of some oysters; increased mortality would also occur in stagnant portions of the system. Refilling and restoration

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of the system to operation could then result in the release of some I top shells and carrying of unattached live organisms into portions of i

the system which were normally trouble-free. It should be noted that

'the problems are apparently related to shutdown activities and are not likely to occur during operation at power.

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.LLER 83-013/03L APPARENT CAUSE'OF 0CCURRENCE: (cont'd)

Settling of ' silt in low 1 flow portions of the service water system has also1been documented, particularly in the case of plugging of CFCU -

flow' transmitter. sensing lines (see LERs 82-028/01X-1 and 82-038/03L).

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The presence of silt in the normally blanked auxiliary feedwater pump '

supply cross-connect-line is consistent with previously observed problems.

ANALYSIS OF OCCURRENCE:

' Operability of the Service Water System ensures that sufficient cooling. capacity is available for. continued operation of safety related equipment during accident conditions. A boron injection system is required to be operable during Mode 6 operations to insure reactivity control. capability is maintained.

The Auxiliary Feedwater System ensures that the Reactor' Coolant System can.be. cooled to less than~350 F from normal operating conditions, in the event of a total loss of offsite power. The cross-connect to the Auxiliary Feedwater System is required to be available in.30 minutes in the event of a complete loss of A.C. power coincident with tornado missile damage to all redundant-normal auxiliary feedwater supplies (auxiliary feedwater storage tank, demineralized water storage tanks, and fire protection / domestic water storage tanks).

As mentioned, the . occurrences were apparently. the result of shutdown maintenance activities, and would.not have likely occurred during operation in; elevated moder. Based on the initial results of an evaluation by the system Sponsor. Engineer, - the silt present in the auxiliary'feedwater supply cross-connect would not have interfered.

with the availibility of the supply or the proper function of the Auxiliary Feedwater System.

Action. Statement'3.1.2.3 applies in-Mode 6 and' requires:

With no charging pump operable, suspend all operations involving core alterations or positive reactivity changes until at least one charging pump is restored to' operable status.

As-noted no core alterations or reactivity changes were conducted. . in compliance with the action statement. Due to this and the general confinement of the problems to shutdown modes. no risk to the health or safety of the ' public was involved. Because of operation in a degraded mode permitted by a limiting condition for operation, the occurrence is reportable in accordance with Technical Specification 6.9.1.9b.

.- CORRECTIVE ACTION:

~As stated, core alterations and reactivity changes were suspended

.during inoperability of the charging pump. Remedial action was taken to clean or flush out the shells-from the portions of the Service Water System involved. At 1315 hours0.0152 days <br />0.365 hours <br />0.00217 weeks <br />5.003575e-4 months <br />, April 10, 1983, No. 22 Charging Pump was restored'to operation and was satisfactorily tested. The pump was declared operable and Action Statement 3.1.2.3 was w.-..- - - - - - , - - , - . ,an-,.- _ . . . -e.-,,---.-e. %m--.-%,-.,ww.w ..-----.--,*--wc,%,,-e, -=----,---,,,,=e%,-,mo---w--,---wm 9w e,- c, 3,-w e t , , v ,, .-y

- LE'R 83-013/03L CORRECTIVE ACTION: (cont'd) terminated. The other safety related components involved were also satisfactorily tested and demonstrated to be operable.

Development of a chlorination program to fully eliminate the oysters from the Service Water System and to prevent reinfestation is in progress. Design Change Request 2EC-1327 has been submitted to provide continuous chlorine monitoring at the Circulating Water System discharge. The modification will allow increased levels and durations of chlorination.

Due to concern over the overall problem of oysters in the Service Water System, a formal Safety Evaluation will be performed prior to the unit startup. Initial results of engineering investigation indicate that operation may safely proceed with only minor modification of the existing chlorination program. A one-time, increased chlorination will be performed to kill soft-bodied organisms, followed by a flush and inspection of the system. Any plugged components will be cleaned as necessary. A commitment to submit a Supplemental Report upon resolution of the oyster problem in general was made in LER 82-041/03L.

With respect to the accumulation of silt in the Auxiliary Feedwater System supply cross-connect, a Design Change Request will be issued to relocate the cross-connect isolation valve to eliminate future deposition of silt in the line.

FAILURE DATA:

Not Applicable Prepared By R. Frahm I 4N! # /

/ ' G6neral Manager -

F Salem Operations SORC Meeting No.83-060 l

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