ML20045B957

Suppl Special Rept 1-93-004 Re 930212 Failure of Latch Arm Gasket on Deluge Valve 20,resulting in Leak in Valve Pit.Due to Repeated Failures of Replacement Gaskets,Valve Will Not Be Repaired & Operable by 930415,as Stated in 930329 Ltr

ML20045B957
Person / Time
Site:	Brunswick
Issue date:	06/15/1993
From:	Jonathan Brown CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
1-93-004, 1-93-4, BSEP-93-0079, BSEP-93-79, NUDOCS 9306210314
Download: ML20045B957 (1)

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Cp&L en.w.s wm Carolina Power & Light Company iC2WM Brunswick Nuclear Plant P. O. Box 10429 l Southport, NC 28461-0429 JUN 151993 Files B09-13510C Serial BSEP 93-0079 U. S. Nuclear Regulatory Commission ,

ATTNs Document Control Desk ,

Washington, DC 20555 BRUNSWICK STEAM ELECTRIC PLANT, UNIT 1 AND 2 DOCKET NOS. 50-325 & 50-324 LICENSE NOS. DPR-71 & DPR-62. j SUPPLEMENTAL SPECIAL REPORT l-93-004 Gentlemen:

On March 29, 1993, Brunswick Nuclear Plant mailed Special Report (SR) 1-93-004 l to the Nuclear Regulatory Commission (see attached). The Special Report detailed i

plans to repair Deluge Valve 20. Specifically, the valves latch arm gasket was' to be replaced and the valve declared operable by April 15, 1993.  ;

The plan was changed due to repeated failures of the replacement gaskets. The ,

cause of the failures could not be determissed; therefore, a system redesign is being developed to permanently modify the system. In the interim, a_ temporary modification was performed on DV-20 to place a steel plate over the latch arm gasket and to remove the valve internals. The associated sprinkler system was placed in service and the LCO was canceled on April 28, 1993.

1 The NRC Senior Resident Inspector for the Brunswick Nuclear Plant was notified  ;

on April 15, 1993 that the system would not be returned to service by the date specified in the special report. This letter is to notify you of the revised i corrective actions taken and to inform you of the current status of the deluge i valve. As stated in the March 29 letter, the methods for permanent repair will  !

be provided in a supplemental report by July 1, 1993.  !

Yours very truly, 18005G J dw M. Brown, Unit 1 Plant Manager JFM/jfm Enclosures SR l-93-004 cc: Mr. S. D. Ebnet'er Mr. P. D. Milano BSEP NRC Residents Office 9306210314 930615 PDR Y / I ADOCK 05000325 $ / i S PDR l 1 q L a

ttachment 1 CfNLL Carolina Power & Light Company Brunswick Nuclear Plant P. O. Box 10429 Southport, NC 28461-0429 FILE: B09-13510C MAR 2 91993 f[

SERIAL: BSEP-93-0033 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 BRUNSWICK STEAM ELECTRIC PLANT UNIT 1 DOCKET No. 50-325 LICENSE NO. DPR-71 SPECIAL REPORT PER TECHNICAL SPECIFICATION "l.7.8 AND PURSUANT TO TECHNICAL SPECIFICATION 6.9.2 (SR 1-93-004)

Gentlemen:

Unit 1 was in Cold Shutdown for the outage started on April 21, 1992. The following summarines fire protection Limiting Condition for Operation (LCO) Al-93-F0172:

On February 12, 1993, the latch arn gasket failed on Deluge Valve 20 causing a leak in the valve pit. Deluge valve 20 is the supply valve for the Unit 1 Reactor Building sprinkler system. Failure of the gasket causes a system leakage problem but does not of itself render the fire protection system inoperable.

This is an original design problem with the deluge valves. At 0635, the deluge valve was isolated to allow investigation into the cause of the gasket failure.

A Limiting condition of Operation was initiated and compensatory actions were placed in ef fect. The gasket is scheduled to be replaced and the system declared operable by Apt-il 15, 1993.

Brunswick Nuclear Plant believes that gasket failure in these valves is due to a design deficiency. An investigation is in progress to identify methods for permanent repair. An updated status report will be provided by July 1, 1993.

Continuous firewatches have been placed in five areas of the Reactor. Building (north and south -17'0" elevation, north and south 20'0" elevation and north 50'0" elevation). Backup fire suppression is the Reactor Building Standpipe System. Compensatory measures will remain in effect until the Deluge Valve can

r e.*

be returned to service. The special report is required due to the system Deing inoperable longer than the 24 days required by Technical Specifications.

Very truly yours,

, w mM Fon R. E. Morgan, Plant Manager Unit 1 Brunswick IJuclear Plant cc: Mr. S. D. Ebneter Mr. P. D. Milano 'I BSEP NRC Resident Office l f

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