ENS Event | |
|---|---|
13:34 May 30, 2026 | |
| Title | |
| Event Description | The following information was provided by the licensee via phone and email:
This 60-day optional telephone notification is being made in lieu of a licensee event report (LER) as allowed by 10 CFR 50.73(a)(1). This notification is made pursuant to the reporting requirements specified in 10 CFR 50.73(a)(2)(iv)(A) for an invalid actuation of one of the systems listed in 10 CFR 50.73(a)(2)(iv)(B). At approximately 0634 MST on 5/30/2026, Palo Verde Nuclear Generating Station Unit 2 had an invalid actuation of the train 'B' balance of plant engineered safety feature actuation system (BOP ESFAS). This resulted in an auto start of the train 'B' essential chiller, spray pond pump, essential cooling water pump, high pressure safety injection, low pressure safety injection, containment spray, and auxiliary feedwater pump. No valves actuated and the plant remained stable. This event was the result of an invalid BOP ESFAS actuation due to a load sequencer failure. Since the actuation was not initiated in response to actual plant conditions, it was not an intentional manual initiation, and there were no parameters satisfying the requirements for initiation of the systems, this event has been determined to be an invalid actuation. There was no impact on the health and safety of the public or plant personnel. The NRC Resident has been notified. |
| Where | |
|---|---|
Palo Verde  Arizona (NRC Region 4) | |
| Reporting | |
| 10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation | |
| Time - Person (Reporting Time:+1300.12 h54.172 days <br />7.739 weeks <br />1.781 months <br />) | |
| Opened: | Lorraine Weaver 17:41 Jul 23, 2026 |
| NRC Officer: | Brian P. Smith |
| Last Updated: | Jul 23, 2026 |
| 58378 - NRC Website
Loading map... | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 583782026-05-30T13:34:00030 May 2026 13:34:00
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