ENS 47960
ENS Event | |
|---|---|
18:48 May 24, 2012 | |
| Title | Manual Reactor Scram Due to a Loss of Feed as Result of a Loss of Switchgear |
| Event Description | At 1348 CDT on 5/24/12 with the Reactor at 33% power, River Bend Station operators inserted a manual reactor scram based on loss of high pressure feed to the reactor following a loss of a 13.8 Kv switchgear.
The Control Room team observed an electrical transient in the Control Room concurrent with the start of Reactor Feed Pump "B". The crew identified that no high pressure feed was aligned to the reactor and inserted a manual scram. Based on the configuration of the electrical plant during startup, all circulating water and Normal Service Water (NSW) was supplied from NPS-SWG1B. MSIVs were closed based on loss of circulating water and Standby Service Water (SSW) initiated automatically based on loss of NSW. EOP-0001, 'RPV Control' was entered on reactor high pressure and reactor low water level. EOP-0002, 'Primary Containment Control' was entered based on primary containment pressure high and suppression pool level high. EOP-0003, 'Secondary Containment Control', was entered on annulus pressure high. Reactor water level control is being maintained with Reactor Core Isolation Cooling (RCIC). High pressure core spray was manually started but was not required and was subsequently shut down. Pressure control is via RCIC and Safety Relief Valves (SRVs). Safety related busses are aligned to offsite power as normal. They were not affected by the electrical transient. Immediately after the scram at 1350, a report from the Turbine Building indicated smoke was seen around the Reactor Feed Pump 'B' termination cabinet. The Fire Brigade was activated. At 1358, the Fire Brigade reported that there was no fire. A review of the Emergency Action Levels (EALs) was performed. No emergency declaration was required. Initial investigation shows damage to cabling and circuit boards associated with Reactor Feedpump 'B' in the Turbine Building, but no fire was ever observed. In addition, the Technical Support Center (TSC) and Operations Support Center (OSC) lost power. At the time, both facilities continued to be in a state of readiness and emergency functions could be performed. At 1526, power was restored to both facilities, including the ventilation systems. All rods inserted into the core. The unit is stable at 230 psi and 391 degrees F. Reactor pressure is maintained by RCIC and decay heat removal via safety relief valves to the suppression pool. The unit is in a technical specification for suppression pool high level. There were no safety system failures. There is one non safety related 13.8 switchgear out of service due to this event and NNS-Switchgear 2A out of service from an event three days ago. Offsite assistance was not required. The NRC Resident Inspector has been notified. |
| Where | |
|---|---|
River Bend  Louisiana (NRC Region 4) | |
| Reporting | |
| 10 CFR 50.72(b)(2)(iv)(B), RPS Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | |
| Time - Person (Reporting Time:+-0.73 h-0.0304 days <br />-0.00435 weeks <br />-9.99954e-4 months <br />) | |
| Opened: | Steven Carter 18:04 May 24, 2012 |
| NRC Officer: | Joe O'Hara |
| Last Updated: | May 24, 2012 |
| 47960 - NRC Website | |
River Bend with 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 | |
WEEKMONTHYEARENS 568872023-12-13T07:02:00013 December 2023 07:02:00
[Table view]10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram ENS 568632023-11-18T05:55:00018 November 2023 05:55:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Scram ENS 551692021-04-02T15:17:0002 April 2021 15:17:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram Due to Turbine Trip ENS 551542021-03-25T14:18:00025 March 2021 14:18:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Trip Due to Lowering Condenser Vacuum ENS 548492020-08-21T14:18:00021 August 2020 14:18:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram ENS 540962019-06-01T04:45:0001 June 2019 04:45:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Scram Due to Low Reactor Water Level ENS 537322018-11-10T05:00:00010 November 2018 05:00:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram on High Reactor Pressure ENS 531922018-02-01T16:57:0001 February 2018 16:57:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram ENS 529152017-08-19T01:55:00019 August 2017 01:55:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Scram While at 100 Percent Power ENS 528252017-06-24T01:18:00024 June 2017 01:18:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram on Main Generator Trip ENS 526022017-03-10T13:14:00010 March 2017 13:14:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram Due to Closure of the Main Turbine Control Valves ENS 517012016-01-29T21:18:00029 January 2016 21:18:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Specified System Actuation After Loss of One Offsite Power Source ENS 516442016-01-09T08:37:0009 January 2016 08:37:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram on Main Steam Isolation Due to Electrical Fault ENS 515682015-11-27T10:31:00027 November 2015 10:31:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram Following Partial Loss of Offsite Power ENS 511122015-06-02T02:11:0002 June 2015 02:11:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Reactor Scram Due to Low Reactor Water Level ENS 508722015-03-08T03:40:0008 March 2015 03:40:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Specified System Actuation Due to Loss of One Reserve Station Service Offsite Power Source ENS 507042014-12-25T14:37:00025 December 2014 14:37:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram ENS 505462014-10-17T08:03:00017 October 2014 08:03:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram on High Average Power Range Monitor Flux ENS 491222013-06-16T09:56:00016 June 2013 09:56:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Broken Damper Blade Linkage Found on Technical Support Center Ventilation Line ENS 485552012-12-04T15:42:0004 December 2012 15:42:00 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release, 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Licensee No Longer Has Control of Emergency Sirens ENS 479952012-06-05T10:02:0005 June 2012 10:02:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Filter Train Inoperable ENS 479602012-05-24T18:48:00024 May 2012 18:48:00 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 Scram Due to a Loss of Feed as Result of a Loss of Switchgear ENS 479402012-05-21T19:52:00021 May 2012 19:52:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram Resulting from a Low Condenser Vacuum-Turbine Trip ENS 475492011-12-23T12:10:00023 December 2011 12:10:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram Due to a Turbine Trip ENS 458362010-04-13T10:01:00013 April 2010 10:01:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Ventilation System Out of Service ENS 453882009-09-29T16:27:00029 September 2009 16:27:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Loss of Water from Upper Refuel Pool ENS 453692009-09-20T22:47:00020 September 2009 22:47:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Scram Due to Reactor Recirc Pump Trip ENS 440342008-03-05T20:43:0005 March 2008 20:43:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Scram Due to Apparent Malfunction in Turbine Control System ENS 440132008-02-28T18:38:00028 February 2008 18:38:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness "Planned Maintenance on Safety Parameter Display System (Spds) and Emergency Response Data System (Erds) ENS 439522008-02-01T19:45:0001 February 2008 19:45:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Scheduled Loss of All Main Control Room Annunciators to Support Plant Maintenance ENS 439112008-01-17T15:17:00017 January 2008 15:17:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Control Room Annunciators Removed from Service for Planned Maintenance ENS 439042008-01-14T22:10:00014 January 2008 22:10:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Planned Loss of Main Control Room Annunciator System ENS 439012008-01-13T16:36:00013 January 2008 16:36:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Emergency Assessment Capabilities Due to Planned Maintenance Activities ENS 437732007-11-07T09:06:0007 November 2007 09:06:00 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)(2)(iv)(A), System Actuation - ECCS Discharge Reactor Scram as a Result of Loss of Normal Power 13.8 Kv Bus ENS 436682007-09-27T03:44:00027 September 2007 03:44:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram During the Performance of Aprm Surveillance Testing ENS 433452007-05-04T17:56:0004 May 2007 17:56:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram Due to Loss of Cooling to Number 2 Main Transformer ENS 429212006-10-19T22:56:00019 October 2006 22:56:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident, 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge Automatic Scram Following Spontaneous Feedwater Valve Closure ENS 425052006-04-15T21:15:00015 April 2006 21:15:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Reactor Scram from 100% Power ENS 413392005-01-15T08:12:00015 January 2005 08:12:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram Due to Receiving a Main Generator Alarm ENS 412522004-12-10T19:17:00010 December 2004 19:17:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Reactor Scram Due to Loss of Vital Instrument Bus ENS 411652004-11-01T22:44:0001 November 2004 22:44:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Emergency Diesel Generator Automatic Start ENS 411642004-11-01T03:56:0001 November 2004 03:56:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Plant Had Auto Start of the Division 1 Emergency Diesel Generator ENS 410822004-10-01T12:30:0001 October 2004 12:30:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge Reactor Trip Due to Main Generator Load Rejection ENS 409572004-08-15T09:05:00015 August 2004 09:05:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram Following Partial Loss of Offsite Power ENS 401912003-09-23T03:43:00023 September 2003 03:43:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram Received During Main Turbine Control Valve Testing 2023-12-13T07:02:00 | |