ENS 56295
ENS Event | |
|---|---|
06:48 Jan 4, 2023 | |
| Title | High Pressure Coolant Injection Inoperable |
| Event Description | The following information was provided by the licensee via email:
At 0148 EST on January 4, 2023 it was identified that P4400F603B, Division 2 Emergency Equipment Cooling Water (EECW) Supply Isolation Valve, lost position indication. Division 2 EECW System was declared inoperable due to the potential that this valve may not be capable of performing its safety function to automatically isolate the safety related Division 2 EECW system from the non-safety related Reactor Building Closed Cooling Water (RBCCW) system. Because the Division 2 EECW system provides cooling to the High Pressure Coolant Injection (HPCI) room cooler, HPCI was also declared inoperable; therefore, this condition is being reported as an eight-hour, non--emergency notification per 10 CFR 50.72(b)(3)(v)(D). At 0240 EST, position indication was restored and Division 2 EECW and HPCI was returned to operable following inspection of the associated motor control center (MCC) and testing of the associated fuses. The cause of the loss of indication is under investigation. The Senior NRC resident inspector has been notified.
The following retraction was received from the licensee via email: The purpose of this notification is to retract a previous Event Notification, EN 56295, reported on 1/4/2023. Following the initial EN, further analysis of the condition was performed utilizing a gothic analysis model to perform HPCI room heat-up calculations. Based on the initial conditions at the time of the indication loss, specifically HPCI room and Suppression Pool temperature, it was determined that the resulting worst case post-accident room temperature was sufficiently low enough to provide margin to HPCI operability without the room cooler in service for the required mission time. No other concerns were noted during the event. Therefore, HPCI remained operable and there was no loss of safety function. The event did not involve a condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident under 10 CFR 50.72(b)(3)(v)(D). Therefore, the NRC non-emergency 10 CFR 50.72(b)(3)(v)(D) report was not required and the NRC report 56295 can be retracted and no Licensee Event Report under 10 CFR 50.73(a)(2)(v)(D) is required to be submitted. The NRC Senior Resident Inspector has been notified. Notified R3DO (Ruiz). |
| Where | |
|---|---|
Fermi  Michigan (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
| Time - Person (Reporting Time:+1.67 h0.0696 days <br />0.00994 weeks <br />0.00229 months <br />) | |
| Opened: | Whitney Hemingway 08:28 Jan 4, 2023 |
| NRC Officer: | Ian Howard |
| Last Updated: | May 4, 2023 |
| 56295 - NRC Website | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |