05000219/LER-1983-003, Forwards LER 83-003/03L-0.Detailed Event Analysis Encl

Forwards LER 83-003/03L-0.Detailed Event Analysis Encl

ML20071A900
Person / Time
Site:	Oyster Creek
Issue date:	02/15/1983
From:	Fiedler P GENERAL PUBLIC UTILITIES CORP.
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20071A902	List: 05000219/LER-1983-003, Forwards LER 83-003/03L-0.Detailed Event Analysis Encl
References
NUDOCS 8302250216
Download: ML20071A900 (3)

LER-2083-003, Forwards LER 83-003/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
2192083003R00 - NRC Website

text

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GPU Nuclear NU@IQf P.O. 83ox 388 Forked River, New Jersey 08731 609-693-6000 l Writer's Direct Dial Number: l l

February 15, 1983 Mr. Ronald C. Haynes, Administrator Region I U.S. Nuclear Regulatory Commission ,

631 Park Avenue  !

King of Prussia, PA 19406

Dear Mr. Haynes:

Subj ect: Oyster Creek Nuclear Generating Station Docket No. 50-219 Licensee Event Report Reportable Occurrence No. 50-219/83-03/03L This letter forwards three copies of a Licensee Event Report (LER) to report Reportable Occurrence No. 50-219/83-03/03L in compliance with paragraph 6.9.2.b.2 of the Technical Specifications.

Very truly yours, Peter B. Fiedler Vice President and Director Oyster Creek PBF:jal Enclosure s cc: Director (40 copies)

Office of Inspection and Enf orcement U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Director (3)

Of fice of Management Information and Program Control U.S. Nuclear Regulatory Commission Washington, D.C. 20555 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, NJ 08731 8302250216 830215 PDR ADOCK 05000219 S PDR GPU Nuclear is a part of the General Public Utilities System p

OYSTER CREEK NUCLEAR GENERATING STATION Forked River, New Jersey 08731 Licensee Event Report Reportable Occurrence No. 50-219 /83-03/03L Report date Februarya15, 1983 Occurrence date January 18, 1983 Identification of Occurrence "A" Control Rod Drive (CRD) pump was taken out of service for maintenance.

This condition constitutes operation in a degraded mode permitted by a limiting condition for operation as specified in Technical Specification paragraph 3.4.D.2. While performing maintenance on "A" CRD pump, a vent line on the pump was broken of f. This resulted in the wetdown of NZOIA core spray pump and the inadvertent trip of "B" CRD pump. Core spray pump NZOIA was removed from service temporarily, which constitutes operation in a degraded mode permitted by a limiting condition for operation specified in Technical Specification paragraph 3.4.A.4.

This event is considered to be a reportable occurrence as defined in the Technical Specifications, paragraph 6.9.2.b.2.

Conditions Prior to Occurrence The plant was operating at steady state power:

Reactor Power 931 MWt Generator Output 250 MWe Mode Switch Position Run Description of Occurrence "A" CRD pump was removed f rom service in order to torque the pump The casing nuts.

break While performing this function, a pump vent line was broken off.

caused a discharge of water from the pump vent line. The mechanic, to avoid During this movement, the discharging water, quickly moved away from the pump. "B" CRD the low suction pressure switch for "B" CRD pump was disturbed. The pump tripped as a rescit. The control room operator noticed the shutdown and immediately restarted "B" CRD pump.

The discharged water from "A" CRD pump vent line fell on NZOIACore core spray pump spray pump which is located on a floor level beneath the "A" CRD pump.

NZOIA was removed from service to megger the pump motor for possible water damage.

-4 .,

Reportable Occurrence Page 2 Report.No. 50-219/83-03/03L Apparent Cause' of Occurrence 3

A".CRD pump was removed from service to torque the pump casing nuts.' This'was done in an attempt to stop a slight leak emanating from a pump casing bolt.

' The broken vent line resulted in the wetting down of NZOIA core spray pump, which is directly below "A" CRD pump.

I. In an attempt to avoid t S ie vent line discharge from "A" CRD pump, the mechanic l inadvertently disturbed the low suction pressure switch resulting in the trip -

l of "B" CRD pump.

Analysis of Occurrence I

The CRD pump supplies control rod drive cooling water, accumulator charging and I rod maneuvering pressure as well as make-up water to the reactor core. For l pipe break sizes up to 0.002 f t.2, the flow from a single CRD pump is adequate for maintaining the reactor vessel water level above the core, thus alleviating the need for actuation of the Auto Depressurization System and core spray-initiation.

I The intended function of the Core Spray System is to provide cooling water to the fuel assemblies in the event of a loss of coolant accident. The Core Spray-System consists of two identical systems, each of .which contain two redundant loops. Each of the loops have both a main and booster. pump and associated piping and valves necessary to meet the design flow of the system. This evcat was limited to the loss of a single active component in .one of the core spray loops.

l As the redundant "B" CRD pump' was immediately restarted af ter its trip.and remained operating, and as the redundant core spray system was operable and the redundant core spray pump in the af fected loop was demonstrated to be operable as required by Technical Specification 3.4.A.4, the safety significance is considered minimal.

Corrective Action Immediate corrective action was to restart 'B' CRD pump af ter its trip. Core spray pump NZOIA was removed from service to perform a megger check of the pump motor to assess possible water damage. Core spray pump NZOIA and ' A' CRD pump were subseq' .ntly returned to service.

An evaluation has been initiated to provide a ineans of preventing the inadvertent wetting of the core spray pumps be' low the CRD pumps.

Failure Data None i

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