ENS 49723
ENS Event | |
|---|---|
19:20 Oct 16, 2013 | |
| Title | Technical Support Center Out of Service |
| Event Description | On 10/16/2013 at 14:20 [CDT], the Technical Support Center (TSC) Emergency Makeup Filter Flow Control Damper (OVV145Y) was discovered degraded and non functional during planned maintenance activities. The degraded damper adversely impacted the TSC ventilation system function.
On 10/16/2013 at approximately 15:00 [CDT], administrative actions were developed and briefed to isolate instrument air to the degraded nonfunctional damper OVV 145Y providing the capability to restore TSC Emergency Makeup Filter functionality. Isolating instrument air to the degraded damper places the damper in the failed open position, thereby restoring TSC Emergency Makeup Filter functionality. On 10/16/2013 at 20:25 [CDT], instrument air was isolated to the degraded damper OVV 145Y under administrative controls restoring TSC Emergency Makeup Filter functionality. This action was taken after determining no adverse affects on system operation. On 10/30/2013, degraded damper OVV145Y was repaired, instrument air restored and post maintenance testing completed, thereby restoring the degraded TSC emergency Makeup Filter Unit flow control damper functionality. This event is reportable per 10CFR50.72(b)(3)(xiii) for a major loss of emergency assessment capability because the emergent degraded TSC flow control damper OVV145Y adversely impacted the function of TSC Emergency Makeup Filter and was not restored within the TSC activation time (60 minutes). This event was originally determined not reportable because the capability to restore within the TSC activation time (60 minutes) existed from the time of discovery. Upon further review it was determined to be reportable because the degraded damper 0VV145Y was not restored to service within the TSC activation time (60 minutes). The licensee has notified the NRC Resident Inspector. |
| Where | |
|---|---|
Braidwood  Illinois (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | |
| Time - Person (Reporting Time:+2158.22 h89.926 days <br />12.847 weeks <br />2.956 months <br />) | |
| Opened: | Joe Conquest 18:33 Jan 14, 2014 |
| NRC Officer: | Vince Klco |
| Last Updated: | Jan 14, 2014 |
| 49723 - 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 %) |
WEEKMONTHYEARENS 563522023-02-06T11:30:0006 February 2023 11:30:00
[Table view]10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Communications and Assessment Capabilities ENS 553252021-06-24T14:01:00024 June 2021 14:01:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Technical Support Center Capability ENS 540902019-05-26T00:30:00026 May 2019 00:30:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Main Control Room Area Radiation Monitors ENS 531802018-01-23T10:00:00023 January 2018 10:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Assessment Capability Due to Technical Support Center Planned Maintenance ENS 521032016-07-18T20:00:00018 July 2016 20:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Offsite Communications Capability ENS 511542015-06-15T12:00:00015 June 2015 12:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Tsc Ventilation to Be Removed from Service for Planned Maintenance ENS 510922015-05-27T14:45:00027 May 2015 14:45:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Out of Service for Planned Maintenance ENS 509572015-04-06T13:09:0006 April 2015 13:09:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Out of Service for Planned Maintenance ENS 509332015-03-27T14:41:00027 March 2015 14:41:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Seismic Monitor Not Available for Emergency Plan Assessment ENS 504312014-09-06T11:13:0006 September 2014 11:13:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Air Conditioning Condensing Units Out of Service ENS 503972014-08-25T10:00:00025 August 2014 10:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Planned Maintenance ENS 502472014-07-01T12:15:0001 July 2014 12:15:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Offsite Alert and Notification System Failure ENS 501622014-06-01T18:14:0001 June 2014 18:14:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Technical Support Center Cooling Capability ENS 497232013-10-16T19:20:00016 October 2013 19:20:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Out of Service ENS 483282012-09-21T01:35:00021 September 2012 01:35:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Ventilation Inoperable ENS 478452012-04-18T02:30:00018 April 2012 02:30:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Plant Process Computer Removed from Service for Planned Replacement ENS 476222012-01-26T03:00:00026 January 2012 03:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Out of Service Due to Planned Maintenance ENS 467662011-04-19T04:09:00019 April 2011 04:09:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Plant Process Computer Removed from Service for Planned Replacement ENS 435902007-08-23T20:30:00023 August 2007 20:30:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Manual Reactor Trip Because of Lowering Condenser Vacuum ENS 431372007-02-01T15:25:0001 February 2007 15:25:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Offsite Phone Connections ENS 418582005-07-21T00:17:00021 July 2005 00:17:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Emergency Sirens Failed for One Hour ENS 409222004-08-04T12:15:0004 August 2004 12:15:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Emergency Notification Due to Inoperable Sirens 2023-02-06T11:30:00 | |