ML20003C383

AO 50-219/74/28:on 740419,suction Valve V-20-4 to Core Spray Pump B Stuck in Closed Position for 15 Minutes,Causing Loss of Core Spray Redundancy in Sys 2.Cause Undetermined.Valve Manually Opened & Circuit Breaker Tagged Open

ML20003C383
Person / Time
Site:	Oyster Creek
Issue date:	04/19/1974
From:	Menning J JERSEY CENTRAL POWER & LIGHT CO.
To:
References
AO-50-219-74-28, NUDOCS 8103030180
Download: ML20003C383 (3)

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Initial Telephone '

Date of Rep 3rt Date: 4/19/74 Occurrence: 4/19/74 Initial Written Time of R: port Date: 4/19/74 Occurrence: 0715 OYSTER CREEK NUCLEAR GENERATING STATION FORKED RIVER, NEW JERSEY 08731

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Abnormal Occurrence Report No. 50-219/74/28 IDENTIFICATION Violation of the Technical Specifications , paragraph 3.4. A.1, OF OCCURRENCE:

which requires the core spray system to be operable at all times with irradiated fuel in the reactor vessel, except as specified in Specification 3.4. A.3 and 3.4. A.4. Suction valve (V-20-4) to the "B" core spray pump was stuck in the closed .

position for a period of approximately 15 minutes thereby causing a loss of core spray pump redundancy in system II. In addition, core spray systen I was tagged out of service for maintenance at this time.

This event is considered to be an abnormal occurrence as de-fined in the Technical Specifications, paragraph 1.15B and D.

CONDITIONS PRIOR Steady State Power Routine Shutdown TO OCCURRENCE: llot Standby Operation Cold Shutdown Load Changes During X Refueling Shutdown Routine Power Operation Routine Startup Other (Specify)

Operation The reactor mode switch was in the REFUEL position with reactor coolant temperature approximately 104 F.

DESCRIPTION At approximately 0715 on April 19, 1974, while performing sur-0F OCCURRENCE:

veillance testing on core spray system II, motor-operated valve V-20-4 failed to open electrically after having closed electrically in a normal manner. This surveillance testing was being performed f/03030/7b

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Abnormal Occurrence

. R3 port No. 50-219/74/28 Page 2 on core spray system II after system I was tagged out of ser-

• vice for maintenanct . (Hydraulic shock and sway arrestor units were being replaced on components of system I.) V-20-4 was manually opened approximately 15 minutes after this valve prob-lem was identified.

APPAREhT CAUSE Design F a cedure Manufacture b, usual Service Condition OF OCCURRENCE:

Installation / II.c. Environmental Const ruction Component Failure Operator Other (Specify)

The apparent cause of this occurrence has not been identified at this time.

Motor-operated valve V-20-4 provides suction to the "B" core ANALYSIS OF OCCURRENCE:

spray pump in core spray system II. This valve is normally maintained in the open position but is closed whenever required for isolation purposes. Had core spray system operation been required, the "B" core spray pucp would have functioned nor-mally both before performance of the surveillance testing and after the valve was locked in the open position. Only the isolation function of the valve was lost during these two time

. periods . The safety significance of this event is that for a period of approximately IS minutes core spray pump redundancy was lost in system II. Since' system I was tagged out of service during this tine period, a further degradation in core spray system capability resulted.

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Ahnormal Occurrence Report No. 50-219/74/29 page 3 CORRECTIVE 1mmediate corrective action involved manually opening the motor-ACTION:

. operated valve (V-20-4) and tagging open the associated circuit breaker to prevent subsequent closing. Additional corrective actions will be determined following the completion of mainten-ance and review of this incident by the Plant Operations Review Committee.

FAILURE DATA: To be supplied at a later date.

O Prepared by: < h\w m, _

Date:  %\ Pi s'

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