ENS 52961
ENS Event | |
|---|---|
18:53 Jul 14, 2017 | |
| Title | Invalid Actuation of Containment Isolation Valves |
| Event Description | This report is being made as required by 10 CFR 50.73(a)(2)(iv)(A) to describe an automatic actuation of containment isolation valves in more than one system. Because the actuation was invalid, this 60-day telephone notification is being made instead of a written LER [Licensee Event Report], in accordance with 10 CFR 50.73(a)(1).
On 07/14/17, at approximately 1453 hours0.0168 days <br />0.404 hours <br />0.0024 weeks <br />5.528665e-4 months <br /> [EDT], an electrical transient occurred due to an off-site lightning strike that de-energized one of the station's two qualified off-site power sources. This resulted in an automatic fast transfer of four 4 kV electrical buses to the alternate off-site source. The fast transfer occurred as designed without complications. The loss of power had numerous impacts on plant equipment that occurred in accordance with plant design, including a Group 2 primary containment isolation on both units. The Group 2 isolation affected multiple systems, including Reactor Water Cleanup, Instrument Nitrogen, and the Drywell Floor Drain. The fault on the off-site transmission line immediately cleared after the lightning strike and at 1457 hours0.0169 days <br />0.405 hours <br />0.00241 weeks <br />5.543885e-4 months <br /> [EDT] the transmission system operator gave the station permission to reclose the breaker to the off-site source. Following system restorations and equipment walkdowns, plant operators re-established normal connections to the off-site source on 7/14/17 at 2322 hours0.0269 days <br />0.645 hours <br />0.00384 weeks <br />8.83521e-4 months <br /> [EDT] in accordance with station procedures. The containment isolation occurred as a result of the loss of an off-site power source and was not due to actual plant conditions or parameters meeting design criteria for containment isolation. Therefore, this is considered to be an invalid actuation. The NRC Resident Inspector has been informed of this notification. |
| Where | |
|---|---|
Peach Bottom  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation | |
| Time - Person (Reporting Time:+1412.12 h58.838 days <br />8.405 weeks <br />1.934 months <br />) | |
| Opened: | Dan Dullum 15:00 Sep 11, 2017 |
| NRC Officer: | Bethany Cecere |
| Last Updated: | Sep 11, 2017 |
| 52961 - NRC Website | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
Unit 3 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 562802022-11-12T04:33:00012 November 2022 04:33:00
[Table view]10 CFR 50.73(a)(1), Submit an LER 60-DAY Telephonic Notification ENS 548202020-06-08T08:24:0008 June 2020 08:24:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation ENS 529612017-07-14T18:53:00014 July 2017 18:53:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Containment Isolation Valves ENS 519622016-03-28T17:20:00028 March 2016 17:20:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation ENS 500892014-03-09T21:13:0009 March 2014 21:13:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Telephonic Notification for an Invalid Actuation of an Emergency Service Water System ENS 479072012-03-13T20:04:00013 March 2012 20:04:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Report - Invalid Primary Containment Isolation System Actuation ENS 449402009-03-02T15:55:0002 March 2009 15:55:00 10 CFR 50.73(a)(1), Submit an LER Invalid Primary Containment Isolation Signal Due to Maintenance Error ENS 444652008-07-24T03:25:00024 July 2008 03:25:00 10 CFR 50.73(a)(1), Submit an LER Invalid System Actuation Due to Loss of One Offsite Power Circuit to Safety Buses ENS 439102007-12-11T21:45:00011 December 2007 21:45:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Notification of an Invalid Actuation of Units 2 and 3 Primary Containment Isolation Systems ENS 411932004-09-28T06:00:00028 September 2004 06:00:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation Due to Bus Voltage Dip During Recirc Mg Start ENS 411922004-09-18T08:57:00018 September 2004 08:57:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation Due to Off Site Power Source Fast Transfer ENS 408192004-04-25T05:05:00025 April 2004 05:05:00 10 CFR 50.73(a)(1), Submit an LER Invalid System Actuation ENS 401982003-09-25T04:00:00025 September 2003 04:00:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.73(a)(1), Submit an LER Initiation of a Technical Specification Required Shutdown at Peach Bottom 2 ENS 401042003-07-27T22:39:00027 July 2003 22:39:00 10 CFR 50.73(a)(1), Submit an LER 60 Day Optional Report 2022-11-12T04:33:00 | |