ENS 46167
ENS Event | |
|---|---|
16:07 Aug 11, 2010 | |
| Title | Unit 3 Declared an Unusual Event Due to Loss of Annunciators |
| Event Description | While repairing a control room alarm panel, a screw was dropped. This appears to have caused a breaker (3D1B-27) to trip, which caused a loss of greater than 50% of the control room alarm panels.
A team is being assembled to develop trouble shooting plan to restore alarm panels. Enhanced plant monitoring is being put in place until alarm panels are restored. Approximately half of the control room annunciators are locked in and/or non-functional. The licensee notified the NRC Resident Inspector. Notified DHS (Hill), FEMA (Heyman), DOE (Yates), HHS (Baker) and USDA (Shaffer).
At 2130 EDT, Unit 3 exited from the UNUSUAL EVENT based on returning to service greater than 50% of alarm panels. Compensatory measures are in place for the alarm panels which have no audible signal. The licensee notified appropriate state and local agencies. The licensee also notified the NRC Resident Inspector. Agencies that the licensee notified included South Carolina and North Carolina warning points, the South Carolina Emergency Management Agency and the Oconee and Pickens County Emergency Management Agencies. Notified R2DO (Desai), NRR EO (Nelson), IRD Manager (Gott), DHS ( Gates), FEMA (Blankenship), DOE (Bailey), HHS(Grimes) and USDA (Timmons). |
| Where | |
|---|---|
| Oconee South Carolina (NRC Region 2) | |
| Reporting | |
| Emergency class: | Unusual Event |
| 10 CFR 50.72(a) (1) (i), Emergency Class Declaration | |
| Time - Person (Reporting Time:+-3.05 h-0.127 days <br />-0.0182 weeks <br />-0.00418 months <br />) | |
| Opened: | Mike Jones 13:04 Aug 11, 2010 |
| NRC Officer: | Vince Klco |
| Last Updated: | Aug 11, 2010 |
| 46167 - NRC Website
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Unit 3 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 579142025-09-10T16:07:00010 September 2025 16:07:00
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