ML20083B675

Ro:On 831205,fire Barrier Seal Discovered Nonfunctional. Patrol Established & Maint Informed of Impairment.Barrier Will Be Repaired Expeditiously.Foam Seal Not Replaced Following Support Mod Work

ML20083B675
Person / Time
Site:	Diablo Canyon
Issue date:	12/06/1983
From:	Thornberry R PACIFIC GAS & ELECTRIC CO.
To:	Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
NUDOCS 8312210245
Download: ML20083B675 (1)

Text

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ON!M PACIFIC GAS AND E LE C T RIC)mC O M PANY pgg , DIABLO CANYON POWER PLANT i

RO. Box 56 Avila Beach, Cahfomia 9342gg95g35g g g R C. THORNBERRY NANWANAMR g g December 6, 1983 Mr. John B. Martin, Regional Administrator U.S. Nuclear Regulatory Commission, Region V 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596-5368

Dear Mr. Martin:

This confirms a telephone call of 9:45 a.m. PST on December 6,1983 between W. B. Kaefer of PGandE and T. Young of Region V of the NRC concerning a non-functional fire barrier. This notification was made pursuant to Technical Specification 6.9.1.12.b of Appendix A to the Diablo Canyon Unit 1 Operating License.

At approximately 12:30 p.m. PST on December 5,1983, a fire barrier penetration seal was discovered to be non-functional by the plant Fire Marshal. A fire watch patrol was immediately established in accordance with STS 3.7.10. Maintenance personnel have been informed of the impairment and are preparing to repair it expeditiously.

The subject fire barrier is a foam seal around a pipe penetration in the ceiling of fire area 3-B-1 (RHR Pump 1-1 room) which communicates with fire area 3-B-3 (BIT room) above. The foam sealant was removed during support modification work and the penetration was not resealed prior to entering Mode 6 on November 15, 1983. Fire suppression and detection systems in fire area 3-B-1 were operable during this time period. Although hourly patrols were not formally established, prior to December 5, these fire areas were frequently visited by plant personnel.

Fire barriers providing separation between redundant RHR pumps remained

- functional.

Plant management believes this to be an isolated incident based on a preliminary document review and ongoing plant walkdowns.

Sincerely,

$ 0 f& - -

R. C. THORNBERRY ,

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8312210245 031206 PDR S

ADOCK 0500027]

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