ML20210R372
| ML20210R372 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 09/22/1986 |
| From: | Horn G NEBRASKA PUBLIC POWER DISTRICT |
| To: | Martin R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| RTR-NUREG-0654, RTR-NUREG-654 CNSS864329, NUDOCS 8610070284 | |
| Download: ML20210R372 (2) | |
Text
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CNSS864329 September 22, 1986 SEP 2 61986 l
.o Mr. Robert D. Martin Regional Administrator U.S. Nuclear Regulatory Comission Region IV 611 Ryan Plaza Drive Suite 1000 Arlington, Texas 76011
Dear Mr. Martin:
This event summary is submitted in accordance with NUREG 0654, Appendix 1 and CNS Emergency Plan Implementing Procedure (EPIP) 5.7.2 to close out the Notification of Unusual Event (NOUE) declared at 0925, September 21, 1986.
At approximately 0852, September 21, 1986, with the reactor in a run mode, it was noted by Control Room personnel that the Drywell Floor and Equipment Sump integrator registered a 5.65 gpm leak rate. The Shift Supervisor immediately ordered an increased surveillance, in order to verify the indication. The integrator reading was valid.
At 0925, the Shift Supervisor assumed the role of Emergency Director and declared a NOUE based on Emergency Action Level (EAL) 4.1.1.
This EAL stated that a NOUE shall be declared when an unidentified flow of > 5 gpm is indicated. Appropriate notifications were initiated and completed in accordance with EPIP 5.7.6.
Further surveillance of the integrator indicated a 3.41 gpm average leak rate at 1200. Station SORC members met to discuss the situation and elected to remain in the NOUE status until the leak could be identified, even though present leakage was below EAL limits. Planning was initiated in preparation for a Drywell entry at approximately 0000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />. The states of Nebraska and Missouri were notified of this decision along with the NRC.
Entry into the Drywell was accomplished at 0038, September 22, 1986. The area of the leak was identified as the packing on "A" Recirculation Loop discharge valve. Maintenance and Health Physics personnel successfully completed the necessary repairs. A total of eleven CNS personnel took part in this operation. Total exposure received was 422 mR, with a maximum exposure of 75 mR being received by one individual.
At approximately 0310, SORC convened to review the sequence of events, repair evolution, and the results achieved.
Intergrator data and continued surveillance determined that the repair effort was successful.
At approximately 0350, the Emergency Director terminated the NOUE. Closecut notifications were initiated and completed by 0408.
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CNSS864329 September 22, 1986 Page 2 The packing in the above mentioned valve, is currently scheduled for inspection and repair as necessary, during our upcoming outage. This outage is e rently scheduled to begin October 5, 1986.
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. Horn Div on Manager of Nuclear Operations Cooper Nuclear Station GRH/PRW/j s cc:
L. G. Kunci 2
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