ENS 45799
From kanterella
Jump to navigation
Jump to search
ENS Event | |
|---|---|
22:52 Mar 28, 2010 | |
| Title | Alert Declared Due to Fire Affecting Safety Related Equipment |
| Event Description | At approximately 1852 hours0.0214 days <br />0.514 hours <br />0.00306 weeks <br />7.04686e-4 months <br /> Eastern Daylight Time [EDT], on March 28, 2010, with the unit operating at approximately 99.5% power, the H. B. Robinson Steam Electric Plant, Unit No. 2, reactor protection system actuated resulting in an automatic trip of the reactor. At about the time of the reactor trip, there was indication of a loss of the power to the Train 'B' emergency bus. The Train 'B' Emergency Diesel Generator started and provided power to the Train 'B' emergency bus. The Reactor Coolant System pressure response after the reactor trip resulted in the actuation of the Safety Injection System. The reduction in Reactor Coolant System pressure allowed the safety injection system to provide flow to the reactor coolant system, although, there was no indication of conditions that would require the safety injection system to provide flow to the reactor coolant system. Specifically, diagnosis of the event determined that a loss of coolant event, steam generator tube rupture, or secondary system break were not occurring. The safety systems that actuated for this event included the Reactor Protection System, the Safety Injection System, both Emergency Diesel Generators started and the 'B' Emergency Diesel Generator provided power to the 'B' Train Emergency Bus, the Auxiliary Feedwater System actuated, and the three main steam isolation valves closed. The Steam Generator Power Operated Relief Valves are being used for decay heat removal because of the closure of the main steam isolation valves. The Startup Transformer is energized and providing power to the 'A' Train Emergency Bus. Investigation of the cause of the reactor trip and associated emergency system actuations is in progress. At the time of the event, it was noted that there was evidence of a fire condition at 4KV bus number 5 located in the Turbine Building. It is currently believed that this is the cause of the transient condition that resulted in the reactor trip and other emergency system actuations. The reactor is currently being maintained in MODE 3, Hot Standby, conditions.
This event is being reported in accordance with 10 CFR 50.72(b)(2)(iv)(A) for ECCS discharge into the RCS and (B) for RPS actuation, and 10 CFR 50.72(b)(3)(iv)(A) for specified system actuation as described. Additionally, based on an inquiry from the local news media reporter, information regarding this event was discussed with the local media. This contact with the local news media is being reported in accordance with 10 CFR 50.72(b)(2)(xi). All control rods fully inserted on the trip. Volume Control Tank [VCT] level was not dropping consistent with no reactor coolant system leakage. Pressurizer level and pressure drop was indicative of shrink associated with the Reactor Coolant Pump stoppage and cooldown in one loop. The licensee observed no indication of reactor coolant system leakage from the containment sump water level monitors. The licensee informed the NRC Resident Inspector.
The original Non-Emergency classification was reclassified as an ALERT based on the following: A fire on 4kV Bus 5 affected 4kV Bus 4 which caused a loss of 'B' Reactor Coolant Pump which caused a Reactor trip and Turbine Trip. That fire was extinguished without a required event declaration, but a subsequent fire on 4kV Bus 4 required declaration of an ALERT at 2300 [EDT] based on the fire affecting the safety-related 'A' and 'B' DC Buses. The fire was out at 2301 [EDT]. The primary systems are available and control of the Reactor Coolant System has been maintained. The Safety Injection termination Emergency Operating Procedure has been performed and the general procedure for post-trip stabilization is being performed. The licensee informed state/local agencies and the NRC Resident Inspector. Notified R2DO(Guthrie), IRD(Gott), EO(Blount), ET(Leeds), and R2RA(Reyes).
Event Termination Notice for Event 45799. ALERT declaration is no longer required. Event Termination Notice: Current plant Conditions are stable and the conditions that required declaration of the ALERT are no longer present. The fire causing the ALERT classification was extinguished at 2301 [EDT]. There was no explosion or steam line break. The last safety-related DC bus ground was identified and cleared at 0001 [EDT]. The licensee informed state/local agencies and the NRC Resident Inspector. Notified R2DO(Guthrie), IRD(Gott), EO(Blount), DHS(Moore), FEMA(Casto), DOE(Moorone), USDA(Hovey), and HHS(Nunn). |
| Where | |
|---|---|
Robinson  South Carolina (NRC Region 2) | |
| Reporting | |
| Emergency class: | Alert |
| 10 CFR 50.72(a) (1) (i), Emergency Class Declaration 10 CFR 50.72(b)(2)(iv)(B), RPS Actuation 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge 10 CFR 50.72(b)(3)(iv)(A), System Actuation | |
| Time - Person (Reporting Time:+-0.08 h-0.00333 days <br />-4.761905e-4 weeks <br />-1.09584e-4 months <br />) | |
| Opened: | Curtis Castell 22:47 Mar 28, 2010 |
| NRC Officer: | Pete Snyder |
| Last Updated: | Mar 28, 2010 |
| 45799 - NRC Website
Loading map... {"minzoom":false,"maxzoom":false,"mappingservice":"leaflet","width":"350px","height":"250px","centre":false,"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":6,"defzoom":14,"layers":["OpenStreetMap"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","imageLayers":[],"locations":[{"text":"\u003Cb\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003E\u003Ca class=\"mw-selflink selflink\"\u003EENS 45799\u003C/a\u003E - \u003Ca href=\"/Robinson\" title=\"Robinson\"\u003ERobinson\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EAlert Declared Due to Fire Affecting Safety Related Equipment\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 45799 - Robinson\n","link":"","lat":34.40111111111111,"lon":-80.15933333333334,"icon":"/w/images/7/75/Duke_Energy_icon.png"}],"imageoverlays":null} | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | A/R |
| Before | Power Operation (99 %) |
| After | Hot Standby (0 %) |
Robinson with 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(a)(1)(i), Emergency Class Declaration, 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge | |
WEEKMONTHYEARENS 565852023-06-22T14:35:00022 June 2023 14:35:00
[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 Trip Occured During Protection System Testing ENS 542122019-08-11T12:40:00011 August 2019 12:40:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to Turbine Trip ENS 537452018-11-19T05:00:00019 November 2018 05:00:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Emergency Diesel Generator Actuation Due to Low Voltage Signal ENS 526622017-04-04T01:55:0004 April 2017 01:55:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Actuation of Auxiliary Feedwater System During Surveillance Testing ENS 522902016-10-08T17:17:0008 October 2016 17:17:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(a)(1)(i), Emergency Class Declaration, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Unusual Event Declared Due to Loss of Offsite Power ENS 521982016-08-24T17:38:00024 August 2016 17:38:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Reactor Trip Due Automatic Turbine Trip from 100 Percent Power ENS 501782014-06-06T20:22:0006 June 2014 20:22:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Notification of Unusual Event Due to a Fire Alarm Inside Containment ENS 497082014-01-10T03:34:00010 January 2014 03:34:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to Turbine Trip ENS 495062013-11-05T23:00:0005 November 2013 23:00:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to Momentary Loss of 4 Kv Buses and Safety System Actuation ENS 495022013-11-05T05:41:0005 November 2013 05:41:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Actuation of the Auxiliary Feedwater System Due to Main Feed Pump Trip ENS 481992012-08-17T09:52:00017 August 2012 09:52:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Unusual Event Declared Due to the Unplanned Loss of Annunciators > 15 Minutes ENS 477812012-03-28T19:03:00028 March 2012 19:03:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to Steam Generator High Water Level Condition ENS 476182012-01-23T23:04:00023 January 2012 23:04:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Unsual Event Declared Due to Fire Inside Containment Lasting > 15 Minutes ENS 475512011-12-23T21:20:00023 December 2011 21:20:00 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release, 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Alert Declared Due to Halon Discharge During Testing ENS 473022011-09-29T10:02:00029 September 2011 10:02:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Unusual Event Declared Due to Fire Alarm in the Containment ENS 472932011-09-26T15:45:00026 September 2011 15:45:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to One Loop Low Flow Signal ENS 463132010-10-07T04:13:0007 October 2010 04:13:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to a One Loop Reactor Coolant Low Flow ENS 462382010-09-09T18:37:0009 September 2010 18:37:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Reactor Trip Due to Overtemperature Delta-T Signal ENS 457992010-03-28T22:52:00028 March 2010 22:52:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(a)(1)(i), Emergency Class Declaration, 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge Alert Declared Due to Fire Affecting Safety Related Equipment ENS 454832009-11-07T03:02:0007 November 2009 03:02:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip Due to Feed Reg Valve Closure ENS 446602008-11-17T10:51:00017 November 2008 10:51:00 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 High Turbine Vibration ENS 433642007-05-15T15:16:00015 May 2007 15:16:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip on Turbine Trip Due to Differential Generator Protection ENS 429332006-10-25T06:48:00025 October 2006 06:48:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip After a 100% Load Rejection ENS 412962004-12-27T05:31:00027 December 2004 05:31:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Unusual Event Declared Due to Fire Inside Protected Area Lasting Greater than 10 Minutes 2023-06-22T14:35:00 | |
Retrieved from "https://kanterella.com/w/index.php?title=ENS_45799&oldid=425350"