ENS Event | |
|---|---|
13:47 Dec 5, 2011 | |
| Title | Discovery of After-The-Fact Emergency Condition - Unusual Event |
| Event Description | At approximately 0847 EST, Unit 1 Letdown Pressure Control Valve, 1-CH-PCV-1145, began acting erratically which resulted in the Letdown Relief Valve, 1-CH-RV-1203, lifting and flowing to the Pressurizer Relief Tank.
At 0848 EST, the relief valve reseated and the leakage stopped. Approximately 42 gpm leakage resulted from the relief valve lifting. This identified flow rate exceeded the threshold for entry into a Notice of Unusual Event under EAL tab SU6.1 due to identified leakage greater than 25 gpm. The licensee is troubleshooting the Letdown Pressure Control Valve. The licensee notified the NRC Resident Inspector and will notify State and local agencies. |
| Where | |
|---|---|
North Anna  Virginia (NRC Region 2) | |
| Reporting | |
| Other Unspec Reqmnt | |
| Time - Person (Reporting Time:+-4.2 h-0.175 days <br />-0.025 weeks <br />-0.00575 months <br />) | |
| Opened: | Don Taylor 09:35 Dec 5, 2011 |
| NRC Officer: | Mark Abramovitz |
| Last Updated: | Dec 5, 2011 |
| 47497 - NRC Website
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Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 474972011-12-05T13:47:0005 December 2011 13:47:00
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