ENS Event | |
|---|---|
22:00 Dec 29, 2025 | |
| Title | Degraded Condition |
| Event Description | The following information was provided by the licensee via phone and email:
At 1600 CST on 12/29/2025, it was determined that a through-wall leak identified on a three-quarter inch vent valve off of the bonnet of the Unit 1 'B' reactor recirculation flow control valve qualifies as pressure boundary leakage resulting in a degraded reactor coolant system pressure boundary. Leakage repair will be completed prior to plant startup from the current outage. Therefore, this event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A). There was no impact on the health and safety of the public or plant personnel.? The NRC Resident Inspector has been notified. The State of Illinois will be notified. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: This event is related to EN 58100. |
| Where | |
|---|---|
LaSalle  Illinois (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded | |
| LER: | 05000373/LER-2025-002 Manual Scram Due to Degrading Containment Parameters |
| Time - Person (Reporting Time:+-0.87 h-0.0363 days <br />-0.00518 weeks <br />-0.00119 months <br />) | |
| Opened: | Brock Pollmann 21:08 Dec 29, 2025 |
| NRC Officer: | Robert A. Thompson |
| Last Updated: | Dec 29, 2025 |
| 58102 - NRC Website
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Unit 1 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Cold Shutdown (0 %) |
| After | Cold Shutdown (0 %) |
WEEKMONTHYEARENS 581022025-12-29T22:00:00029 December 2025 22:00:00
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