ENS 55859
ENS Event | |
|---|---|
04:40 Mar 7, 2022 | |
| Title | Invalid Actuation 60-DAY Telephone Notification |
| Event Description | The following information was provided by the licensee via fax or email:
This 60-day telephone notification is being made in lieu of an LER submittal per 10 CFR 50.73(a)(1). This notification is made pursuant to the reporting requirements specified in 10 CFR 50.73(a)(2)(iv)(A) for invalid actuations of systems listed in 10 CFR 50.73(a)(2)(iv)(B). At approximately 0040 Eastern Standard Time (EST) on March 7, 2022, Unit 1 received inadvertent High-Pressure Coolant Injection (HPCI) and Reactor Core Isolation Cooling (RCIC) initiation signals. Subsequently, at approximately 0148 EST on March 7, 2022, Unit 1 received inadvertent Low-Pressure Coolant Injection (LPCI) and Core Spray initiation signals. In addition, all four Emergency Diesel Generators auto started, Group 10 (Instrument Air) Primary Containment Isolation System actuations occurred, and the Residual Heat Removal (RHR) Service Water Booster pumps tripped resulting in a brief interruption (approximately 9 minutes) to the Shutdown Cooling (SDC) heatsink. Jumpers, installed per planned refueling outage activities, prevented discharge of Emergency Core Cooling Systems into the reactor. HPCI, RCIC, and RHR Loop `A' were removed from service and under clearance. RHR SDC remained operable via RHR Loop `B' and forced circulation was maintained in the reactor. At the time of these events, Unit 1 was shutdown for refueling and the `A' and `C' reactor water level transmitters had been isolated in preparation for planned replacement. Leak-by of the instrument isolation valves occurred on both transmitters. Leak-by on the `C' instrument occurred at a faster rate with the `A' instrument providing the confirmatory signals resulting in Low Level 2 (LL2) and Low Level 3 (LL3) indication at approximately 0040 EST and 0148 EST, respectively. All actuations occurred as designed for LL2 and LL3 signals. During these events, reactor water level remained stable at the Reactor Vessel Head Flange and the `B' and `D' reactor water level transmitters remained off-scale-high, as expected under these conditions. Therefore, the actuations were not initiated in response to actual plant conditions, it was not an intentional manual initiation, and there were no parameters satisfying the requirements for initiation of the system (i.e., there was no low reactor water level condition). Considering the above, these actuations were invalid. There was no impact on the health and safety of the public or plant personnel. |
| Where | |
|---|---|
Brunswick  North Carolina (NRC Region 2) | |
| Reporting | |
| 10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation | |
| Time - Person (Reporting Time:+1209.55 h50.398 days <br />7.2 weeks <br />1.657 months <br />) | |
| Opened: | Christopher Denton 13:13 Apr 26, 2022 |
| NRC Officer: | Brian P. Smith |
| Last Updated: | Apr 26, 2022 |
| 55859 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Cold Shutdown (0 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 569872024-01-02T04:33:0002 January 2024 04:33:00
[Table view]10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Containment Isolation Valves ENS 569882023-12-28T13:15:00028 December 2023 13:15:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Emergency Diesel Generators ENS 562872022-11-09T14:06:0009 November 2022 14:06:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Containment Isolation Valves ENS 561382022-08-06T10:28:0006 August 2022 10:28:00 10 CFR 50.73(a)(1), Submit an LER 60-DAY Optional Telephonic Notification of Invalid Actuation of Containment Isolation Valves ENS 558592022-03-07T04:40:0007 March 2022 04:40:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation 60-DAY Telephone Notification ENS 557562022-01-04T18:16:0004 January 2022 18:16:00 10 CFR 50.73(a)(1), Submit an LER 60-DAY Optional Telephonic Notification for Invalid Actuation of Containment Isolation Valves ENS 551912021-02-17T19:07:00017 February 2021 19:07:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Containment Isolation Valves ENS 546752020-03-05T14:25:0005 March 2020 14:25:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Telephonic Notification of an Invalid Specified System Actuation ENS 541442019-05-10T00:00:00010 May 2019 00:00:00 10 CFR 50.73(a)(1), Submit an LER 60 Day Optional Notification Due to Actuation of an Emergency Diesel Generator ENS 527782017-04-06T16:12:0006 April 2017 16:12:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Emergency Diesel Generators ENS 520512016-05-09T10:26:0009 May 2016 10:26:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Primary Containment Isolation Valves (Pcivs) ENS 517392016-01-09T14:46:0009 January 2016 14:46:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Emergency Diesel Generator ENS 515052015-09-10T01:03:00010 September 2015 01:03:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of a General Containment Isolation Signal Affecting More than One System ENS 498002013-12-11T13:18:00011 December 2013 13:18:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Primary Containment Isolation System (Pcis) Valves During I&C Maintenance ENS 491682013-05-08T01:14:0008 May 2013 01:14:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Emergency Diesel Generators ENS 489722013-03-04T13:04:0004 March 2013 13:04:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Emergency Diesel Generators ENS 442132008-03-15T20:35:00015 March 2008 20:35:00 10 CFR 50.73(a)(1), Submit an LER Invalid Primary Containment Isolation System (Pcis) Actuation ENS 437912007-09-21T18:10:00021 September 2007 18:10:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Emergency Diesel Generators ENS 416922005-05-12T08:11:00012 May 2005 08:11:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.73(a)(1), Submit an LER Technical Specification Required Shutdown Due to Loss of Emergency Bus E1 ENS 413572004-12-13T21:15:00013 December 2004 21:15:00 10 CFR 50.73(a)(1), Submit an LER Invalid System Actuation ENS 405412004-01-11T11:37:00011 January 2004 11:37:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation ENS 404962003-12-22T03:04:00022 December 2003 03:04:00 10 CFR 50.73(a)(1), Submit an LER Invalid Reactor Building Exhaust Radiation Monitor Signal Resulting in Pcis Isolations 2024-01-02T04:33:00 | |