ML20037C851
| ML20037C851 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 04/26/1974 |
| From: | JERSEY CENTRAL POWER & LIGHT CO. |
| To: | |
| References | |
| AO-50-219-74-28, NUDOCS 8103030144 | |
| Download: ML20037C851 (2) | |
Text
...
OYSTER CREEK NUCLEAR GENERATING STATION
~
FORKED RIVER, NEW JERSEY 08731 Abnormal Occurrence Report No. 50-219/74/28 9'
c,
'!O Rttst0 %
A Report Date MAY l 1974 April 26, 1974 t5-n a man t
r,tnint:R n'aSNEne D Occurrence Date es bl ng April 19, 1974 Identification of Occurrence Violation of the Technical Specifications, paragraph 3.4. A.1, 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 system I was tagged out of service for maint(. nance at this time. This event is considered to be an abnormal occurrence as defined in the Technical Specifications, paragraph 1.15B and D.
Conditions Prior to Occurrence he plant was shut down for refueling.
The reactor mode switch was in the REFUEL position with reactor coolant tem-perature approximately 104*F.
Description of Occurrence At approximately 0715 on April 19, 1974, while performing surveillance testing on core spray system II, motor-operated valve V-20-4 failed to open electrically after having closed electrically in the normal manner. This surveillance test-ing was being performed on core spray system II after system I was tagged out of service for maintenance.
(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 problem was identified.
Apparent Cause of Occurrence he apparent cause of this occurrence has not been identified at this time.
3851 M 2A%1dd
Abnormal Occurrence No. 50-219/74/28 Page 2 Analysis of Occurrence Motor-operated valve V-20-4 provides suction to the "B" core spray pump in core spray system II.
This valve is normally maintained in the open position.
Had core spray system operation been required, the "B" core spray pump would have functioned normally both before performance of the surveillance testing and after the valve war locked in the open position. The safety significance of this event is that for a period of approximately 15 minutes, core spray pump redundancy was lost in system II.
Since system I was tagged out of service during this time period, a further degradation in core spray system capability resulted.
Corrective Action Immediate corrective action involved manually opening the motor-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 the investigation into the cause of this event and a review of the surveillance requirements for this valve will be performed.
Failure Data The cause for this failure has not been identified at this time.
N