ML19332G047
| ML19332G047 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 12/11/1989 |
| From: | Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 89-844, NUDOCS 8912200078 | |
| Download: ML19332G047 (2) | |
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VIRGINIA ELECTRIC AND POWER COMI'ANY RICHMOND, VIRGINIA 23261 l
December 11, 1989 i
U.S. Nuclear Regulatory Commission Serial No.
89 844 Attention: Document Control Desk NO/DEQ/deq Washington, D.C. 20555 Docket Nos.
50 338 50 339-License Nos. NPF 4 NPF-7 Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2 SPECIAL REPORT - KAMAN PROCESS VENT RADIATION MONITOR - RI GW-178 5
At 1627 hours0.0188 days <br />0.452 hours <br />0.00269 weeks <br />6.190735e-4 months <br /> on December 2,1989, with Units 1 and 2 at 98 and 100 percent power (Mode 1), respectively, the Kaman Process Vent Radiation Monitor, RI GW-178, 2
exceeded the Action Statement of Technical Specification 3.3.3.1. Since the Action Statement requires that the radiation monitor be returned to operable status within 7 days or submit a Special Report within 14 days of the event, this event is reportable pursuant to Technical Specification 6.9.2.
The process vent effluent path is continuously monitored by radiation monitor assembly RI-GW 178. On November 25,1989,1-RI-GW 178 began to alarm in the control room every 15 to 30 minutes. The Instrument Department was notified and RI-GW-178 was removed from service at 1627 hours0.0188 days <br />0.452 hours <br />0.00269 weeks <br />6.190735e-4 months <br /> on November 25,1989, to determine the cause of the alarm. Investigation revealed evidence of water in the gas i
sampler chamber and smear results indicated that the check source had started to leach. Leaching of a check source contaminates the gas sampler chamber and Increases the activity.
l The water in the sample lines was a result of condensation due to the heat trace system on the lines being inoperable. Upon receipt of the necessary materials, the l
heat trace system will be repaired. Following completion of the heat trace system repair, the check source will be replaced, RI-GW 178 will be functionally tested and returned to service, and the Action Statement will be cleared. Based on current l
procurement and planning schedules, RI-GW-178 is scheduled to be returned to service by December 22,1989.
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This event posed no significant safety implications because the proplanned alternate t
method of monitoring was established within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> as required by the Technical Specifications. The Westinghouse Process Vent Radiation Monitors, which perform j
the same automatic functions as Rl-GW-178, remained operable throughout this event.
1 Additionally, the Nuclear Research Corporation Radiation Monitors continued to operate throughout this event as the Technical Specification required proplanned-alternate monitoring method on the process vent release path.
l Very truly yours, s
W. L ltewart Senior Vice President Nuclear oc:
U.S. Nuclear Regulatory Commission Region ll 101 Marietta Street, N.W.
Suite 2900 i
Atlanta, Georgia 30323 Mr. J. L. Caldwell NRC Senior Resident inspector North Anna Power Station i
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