PNO-III-87-073, on 870521,personnel Discovered Water Leaking Through Doors on Diesel Fuel Oil Storage Tank Rooms Into Turbine Bldg.Caused by Removal of Wrong Check Valve Bonnet. Water Pumped to Waste Water Treatment Sys for Processing

PNO-III-87-073:on 870521,personnel Discovered Water Leaking Through Doors on Diesel Fuel Oil Storage Tank Rooms Into Turbine Bldg.Caused by Removal of Wrong Check Valve Bonnet. Water Pumped to Waste Water Treatment Sys for Processing

ML20214L981
Person / Time
Site:	Zion File:ZionSolutions icon.png
Issue date:	05/22/1987
From:	Forney W, Greenman E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
References
PNO-III-87-073, NUDOCS 8706010143
Download: ML20214L981 (1)

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PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL 0CCURRENCE--PNO-III-87-73 Date May 22, 1987 t l

This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public 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: Comonwealth Edison Company Licensee Emergency Classification:

Zion Unit 2 Notification of an Unusual Event Zion, IL 60099 Alert Site Area Emergency Docket No. 50-304 General Emergency p1 X Not Applicable v/ ~

Subject:

FLOODING 0F DIESEL GENERATOR FUEL OIL STORAGE TANK ROOM On May 21, 1987, licensee personnel discovered water leaking through the doors (575 foot elevation) of the Unit 2 diesel fuel oil storage tank rooms into the turbine building (560 fa t elevation). The water level in the tank room was approximately 11 feet above the floor. Unit 2 is in a refueling outage, and all fuel has been removed from the reactor.

Approximately 76,000 gallons of water accumulated in the in the 2A room, and approximately 105 gallons of water accumulated in the 2B room.

Tha flooding was caused by contractor personnel on the night shift who removed the bonnet of the wrong check valve in preparation for work on the system supplying cooling water to the diesel generators. Day shift workers subsequently performed the work on the correct check valve in the system and advised the licensee that work was complete. The bonnet of the oth:r check valve -- erroneously removed -- was not replaced when the cooling water system was r stored. Water from the service water system spilled into the tank room; when the flooding was discovered, the service water flow into the system was halted.

The licensee pumped the spilled water to the waste water treatment system for processing.

It is evaluating the condition of the diesel oil transfer pumps which were submerged by the flooding.

The resident inspectors were on-site at the time of the incident. They will monitor the licensee's evaluation of the incident.

Tha State of Illinois will not be notified.

Region III (Chicago) was notified of the flooding incident by the resident inspectors at 4:30 p.m., May 21, 1987. This information is current as of 9 a.m., May 22,1987.

kJ CONTACT: W. orney E. Greenman FTS 388-5590 FTS 388-5518 DISTRIBUTION:

H. St. ED0 NRR E/W Willste Mail: ADM:DMB Chairman Zech PA IE NMSS DOT:Trans only Comm. Roberts ELD OIA RES Comm. Asselstine Com. Bernthal AE0D NRC Ops Ctr 2 dd Comm. Carr SP kD Regional Offices ACRS SECY INP0 2,3 f NSAC 4 3 8 CA RIII Resident Office POR Licensee: .l.'.52) (Corp. Office - Reactor Lic. Only) 8706010143 PDR I&E 870522 F M j3 PNO-III-87-073 PDR  % , ., ,,, C7M