ENS 43124
ENS Event | |
|---|---|
15:15 Jan 26, 2007 | |
| Title | Control Room Emergency Ventilation Air Conditioning (Crev Ac) System Declared Inoperable |
| Event Description | On January 26, 2007 at 0915 hours0.0106 days <br />0.254 hours <br />0.00151 weeks <br />3.481575e-4 months <br />, the Control Room Emergency Ventilation Air Conditioning (CREV AC) system was declared inoperable due to not meeting the surveillance acceptance criteria for the refrigeration condensing unit (RCU) during QCOS 5750-11 (Control Room Emergency Ventilation System Test - performed every 2 years). As result Technical Specification 3.7.5 Condition "A" was entered (30 day Limiting Condition of Operation).
The CREV AC system maintains a habitable control room environment and ensures the operability of components in the control room emergency zone during accident conditions. This notification is being made in accordance with 10 CFR 50.72(b)(3)(v)(D) because the CREV system is a single train system, and loss of the CREV AC could impact the plant's ability to mitigate the consequences of an accident. At this time, additional analysis is underway to determine the impact of the failure to meet the acceptance criteria on the CREV AC safety function. The NRC Resident Inspector was notified of this event by the licensee.
Further evaluation performed by Quad Cities Station confirms the CREV AC system would have performed its safety function. A revised surveillance (QCOS 5750-11, Control Room Emergency Ventilation System Test) was re-performed successfully, and the CREV AC system was declared operable on January 28, 2007 at 0911 hours0.0105 days <br />0.253 hours <br />0.00151 weeks <br />3.466355e-4 months <br />. Based on the subsequent evaluation and surveillance testing, ENS 43124 is being retracted. R3DO (Dave Passehl) notified. The NRC Resident Inspector was notified of this retraction by the licensee. |
| 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:+2.67 h0.111 days <br />0.0159 weeks <br />0.00366 months <br />) | |
| Opened: | Kevin Cravens 17:55 Jan 26, 2007 |
| NRC Officer: | John Mackinnon |
| Last Updated: | Jan 28, 2007 |
| 43124 - NRC Website
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Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (97 %) |
| After | Power Operation (97 %) |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (96 %) |
| After | Power Operation (96 %) |