ENS Event | |
|---|---|
16:07 Sep 10, 2025 | |
| Title | Unusual Event - RCS Identified Leakage Greater than 25 Gpm for Greater than 15 Minutes |
| Event Description | The following information was provided by the licensee via phone and email:
At 1207 EDT on September 10, 2025, Oconee Nuclear Station Unit 1 declared an Unusual Event (SU5.1) due to identified reactor coolant system (RCS) leakage from Unit 1 for greater than 15 minutes. The calculated leak rate was 26 gallons per minute (gpm). The leakage was identified to be from letdown filter 1A, which was subsequently isolated. Units 2 and 3 remain at 100 percent power and are unaffected by this event. This event was terminated at 1353 after isolating the source of the leak. The NRC Resident Inspector has been notified. Notified DHS SWO, FEMA Operations Center, CISA Central Watch Officer, FEMA NWC, DHS Nuclear SSA (email), CWMD Watch Desk (email). |
| 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:+-3.68 h-0.153 days <br />-0.0219 weeks <br />-0.00504 months <br />) | |
| Opened: | Joshua Arnett 12:26 Sep 10, 2025 |
| NRC Officer: | Josue Ramirez |
| Last Updated: | Sep 10, 2025 |
| 57914 - NRC Website
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WEEKMONTHYEARENS 579142025-09-10T16:07:00010 September 2025 16:07:00
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