ENS 50427
ENS Event | |
|---|---|
00:05 Sep 5, 2014 | |
| Title | Control Room Emergency Ventilation (Crev) System Inoperable |
| Event Description | On September 04, 2014, at 1905 hours0.022 days <br />0.529 hours <br />0.00315 weeks <br />7.248525e-4 months <br /> [CDT], the Control Room Emergency Ventilation (CREV) system was declared inoperable due to the Air Handling Unit (AHU) tripping upon restoration of Control Room Ventilation following testing of Reactor Building Ventilation instrumentation. Troubleshooting is in progress at this time.
Technical Specification 3.7.4, Condition A, was entered which requires the CREV system to be restored to an operable status in seven (7) days. Additionally, Technical Specification 3.7.5, Condition A, was entered which requires CREV AC to be restored to an operable status in 30 days. This notification is being made in accordance with 10CFR50.72(b)(3)(v)(D), '[any] event or condition that could have prevented fulfillment of a safety function,' because the CREV system is a single train system required to mitigate the consequences of an accident. The licensee has notified the NRC Resident Inspector.
The purpose of this notification is to retract the ENS notification made on September 4, 2014 (ENS 50427). Upon further investigation it was verified that the function of Control Room Emergency Ventilation System was not affected as discussed in Chapters 6 and 15 of the Updated Final Safety Analysis Report. Therefore, the threshold for reporting the issue as an event or condition that could have prevented the fulfillment of a safety function was not met (NUREG 1022 Revision 3 - Event Report Guidelines Section 3.2.7). The licensee has notified the NRC Resident Inspector and applicable State authorities. Notified R3DO (Pelke) |
| Where | |
|---|---|
Quad Cities  Illinois (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:+0.37 h0.0154 days <br />0.0022 weeks <br />5.06826e-4 months <br />) | |
| Opened: | Mark Bridges 00:27 Sep 5, 2014 |
| NRC Officer: | Howie Crouch |
| Last Updated: | Oct 23, 2014 |
| 50427 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |