PNO-III-88-078, on 880904,fire Occurred in Two Charcoal Adsorber Tanks in Offgas Sys.Cause Under Investigation. Nitrogen Purge of Tanks Performed & Temps Reduced

PNO-III-88-078:on 880904,fire Occurred in Two Charcoal Adsorber Tanks in Offgas Sys.Cause Under Investigation. Nitrogen Purge of Tanks Performed & Temps Reduced

ML20154C586
Person / Time
Site:	Perry
Issue date:	09/06/1988
From:	Cooper R, Knop R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
References
PNO-III-88-078, PNO-III-88-78, NUDOCS 8809140418
Download: ML20154C586 (2)

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PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-ff!-88-78 Date September 06 1988 s

This ireliminary notification constitutes EARLY notice of events of POSSIBLE safety or pu)1ic interest significance. The information is as initially received without verification or evaluation, and is basically all that is known by the Region III staff on this date.

Facility: Cleveland Electric Illuminating Licensee Emergency Classification:

Company X Notification of an Unusual Event Perry Alert Perry, OH 44081 Site Area Emergency General Emergency Docket No. 50-440 Not Applicable

Subject:

FIRE IN TWO CHARC0AL ADSORBER TANKS IN OFFGAS SYSTEM At 10:35 a.m. (EDT), September 4, 1980, while operating at 100 percent power, reacter operators noted that temperatures were gradually increasing in the 12A and 12B offgas system's charcoal adsorber tanks. (The offgas system filters noncondensible gases from the l turbine condenser.)

The operators realigned the system to isolate and bypass the two tanks. (The system contains l two trains of charcoal filters with each train consistin The first tank in j each of the two trains contained the burning charcoal.) g of four tanks.

The licensee declared an unusual event at 12:10 p.m. (EDT), reduced power to 70 percent, and ccmpleted all required notifications within 15 minutes.

, The incident began when the "A" steam jet air ejector automatically isolated on low flow at 9:25 a.m. Over the next five minutes, operators placed the "B" air ejector into service. A slug of noncondensible gases and moisture was introduced into the offgas system. Hydrogen

! concentration spiked to greater than five percent and then returned to nomal (approximately l .2 percent).

! Two auxiliary operators who had been dispatched to refill offgas system loop seals lost during the transient reported hearing a popping noise in the vicinity of the offgas system.

Shor21y thereaf ter, temperatures began increasing in the two tanks, peaking at

! 659.5 degrees F in 12A and 582.2 degrees F in 128. (The cause of the fire has still not been officially detemined and is under investigation.)

i At 2:32 p.m., the licensee began a nitrogen puige of the two tanks. By 8 a.m (EDT),

September 6 the temperature in the 12A tank had been reduced to 6 degrees F, end the temperature in the 128 tank to 67 degrees (nomal temperatures range from 3 to g91g18880906 PNO-!II-88-078 PDC DISTRIBUTIOM:

WFN 1 MNBB 1WFN LEW WFN 1 EaTman Zech Ar011 NF OIA f3GT' Como Roberts ARM 01 SLITP l Como Carr 1WFN Hail To:

Com. Rogers PA Resident Inspector Offices DCS(Original)

SECY OGC Resident Inspector DOT (Trans.Only)

OGC-H FAX TO: Nicholson Lane Regions g )y CA INPO RES Region !

GPA NSAC Region !! c' i ACRS Licensee Region IV POR HQS. Operations Officer Region V Region !!!

Rev. June 1988

PPELI$ NARY E0TIFICATION OF EVENT OR UNUSL'AL OCCURREliCE--PNO-III-88-78 Date September 6, 1988 Throughout the event, offgas system radiation levels remained well within licensed limits.

The unusual event remains in effect. The senior resident inspector arrived onsite at 1 p.m.

(EDT), September 4 and has been monitoring the licensee's courte of action. A Comissioners assistants conference call was held at 5 p.m. (EDT), September 4, to discuss the event. Region III (Chicago) will continue to monitor the event to ensure the fires are completely extinguished before cessation of the nitrogen purge.

The State of Ohio will be notified.

The Headquarters Duty Officer was first informed of this cvent at 12:10 p.m. (EDT),

September 4, 1988. This information is current as of 12:15 p.m. (CDT), September 6,1.988.

CONTACT: R. Cooper R. Knop FTS 388-5578 FTS 388-547 Chm Cmrs, C/R Distribution:

GPA. GC, CA. PDR. Historian.

SECY. Records.

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