ENS 56058
ENS Event | |
|---|---|
17:15 Aug 19, 2022 | |
| Title | Four Automatic Depressurization System Valves Inoperable |
| Event Description | The following information was provided by the licensee via email:
At 1215 CDT on 8/19/2022, with Grand Gulf Nuclear Station in Mode 1 and at 100 percent power, four Automatic Depressurization System (ADS) valves were rendered inoperable due to a loss of system pressure. The station entered Technical Specification 3.5.1 Condition G. This event is being reported under 10 CFR 50.72(b)(3)(v)(D) as an event or condition that could have prevented the fulfillment of a safety function. There were no other systems affected as a result of this condition. The NRC Senior Resident Inspector was notified. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: Plans are to remain in Mode 1 until corrected or until driven by the Technical Specifications to shut down (12-hour LCO from 1215 CDT on 8/19/2022).
Grand Gulf Nuclear Station (GGNS) is performing this notification to retract event EN 56058 that was reported on August 19, 2022. Previously, GGNS notified the NRC that four Automatic Depressurization System (ADS) valves were inoperable due to a loss of system pressure. Based upon further investigation, the condition reported in EN 56058 was found to affect only a single ADS valve. As a result, it was determined that an event or condition that could have prevented the fulfillment of a safety function did not exist at GGNS. Sufficient redundancy existed to perform the safety function. The NRC Resident Inspector has been notified of the retraction. R4DO (Kellar) was notified. |
| Where | |
|---|---|
Grand Gulf  Mississippi (NRC Region 4) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
| Time - Person (Reporting Time:+3.52 h0.147 days <br />0.021 weeks <br />0.00482 months <br />) | |
| Opened: | Paul Lyne 20:46 Aug 19, 2022 |
| NRC Officer: | Donald Norwood |
| Last Updated: | Oct 17, 2022 |
| 56058 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (63 %) |