ML20044G552

Special Rept 93-05:on 930426,fire Barrier for Mechanical Sleeve Between 480-volt Shutdown Board Rooms 1B1 & 1B2 Breached.Caused by Unavailability of Fire Retardant Sealant.Roving Fire Watch Established

ML20044G552
Person / Time
Site:	Sequoyah
Issue date:	05/27/1993
From:	Fenech R TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
93-05, 93-5, NUDOCS 9306030294
Download: ML20044G552 (3)

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b-HA Tennessee Vapey Authority, Post Office Box 2000. Soddy-Daisy, Tennessee 37379-2000.

Robert A. Fenech vice Presdent. Sequoyah Nuclear Plant i

May 27, 1993 U.S. Nuclear Regulatory Commission ATIN: Document Control Desk Washington, D.C. 20555 Gentlemen:

In the Matter of _ _

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Docket No. 50-327 Tennessee Valley Authority

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SEQUOYAH NUCLEAR. PLANT ~(SQN) - UNIT 1 - FACILITY OPERATING LICENSE-DPR,

TECHNICAL' SPECIFICATION (TS) 3.7.12 SPECIAL REPORT 93-05 The enclosed special report provides details concerning a. fire barrier being nonfunctional for a period greater than the TS allowable timeframe.

This report is being submitted in accordance with TS 3.7.12 Action Statement (a).

If you have any questions concerning this submittal, please telephone C. H. Whittemore at (615) 843-7210.

Sincerely, Robert A. Fenech Enclosure cc:

See page 2 9

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' U.S. Nuclear Regulatory Commission Page 2 May 27, 1993 cc (Enclosure):

Mr. D. E. LaBarge, Project Manager U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852-2739 NRC Resident Inspector Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy-Daisy Tennessee 37379-3624 Regional Administrator U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323-2711 l

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s ENCLOSURE 4

SEQUOYAH NUCLEAR PLANT UNIT 1 SPECIAL REPORT 93-05 Description of Event i

On April 26, 1993, with Units 1 and 2 in Mode 5 the fire barrier for the mechanical sleeve between 480-volt Shutdown Board Rooms 1B1 and IB2 was breached. Temporary power cables were routed through the' sleeve for emergency power to the polar crane during the core barrel lift.

This was strictly a contingency action to provide an alternate power source for the polar crane during a critical'11ft in the unlikelihood of an interruption of primary power.

Cause of Condillon The core barrel lif t was performed, the temporary cables were removed, i

and an attempt was made to reestablish the fire barrier. However, the fire retardant sealant used in the mechanical sleeve to establish a fire barrier was not available. The barrier could not be returned to its normal condition within the technical specification (TS) allowable timeframe.

Corrective Actinn In accordance with Limiting Condition for Operation 3.7.12 Action Statement (a), the fire detectors inside the shutdown board rooms were verified operable; a roving fire watch 'was established and will be maintained until the fire barrier is reestablished as required by TSs.

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