ENS Event | |
|---|---|
13:31 May 1, 2020 | |
| Title | Both Secondary Containment Access Doors Open Simultaneously |
| Event Description | At 0831 CDT, the Main Control Room received a 'Reactor Building 903 ft. Access Both Doors Open' alarm. Investigation found the interlock between the inner and outer doors did not prevent the opening of both doors while personnel were accessing the Reactor Building. The doors were immediately closed. Based on alarm times, both doors were open for less than one second. With both doors open, SR 3.6.4.1.3 was not met and Secondary Containment was declared inoperable. This unplanned Secondary Containment inoperability constitutes a condition reportable under 10 CFR 50.72(b)(3)(v)(c) and (d), 'An event or condition that at the time of discovery could have prevented the fulfillment of the safety function of SSCs that are needed to control the release of radioactive material and mitigate the consequences of an accident.'
Secondary Containment was declared operable at 0836 CDT after independently verifying at least one Secondary Containment access door was closed. The NRC Senior Resident Inspector has been informed. |
| Where | |
|---|---|
Cooper  Nebraska (NRC Region 4) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
| Time - Person (Reporting Time:+2.05 h0.0854 days <br />0.0122 weeks <br />0.00281 months <br />) | |
| Opened: | Randy Kouba 15:34 May 1, 2020 |
| NRC Officer: | Donald Norwood |
| Last Updated: | May 1, 2020 |
| 54690 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |