ENS 40318
ENS Event | |
|---|---|
03:22 Nov 13, 2003 | |
| Title | High Pressure Coolant Injection System Isolation During Testing |
| Event Description | During quarterly surveillance testing of the High Pressure Coolant Injection (HPCI) System the HPCI system isolated. The cause of the isolation is believed to be high turbine exhaust diaphragm pressure. HPCI is currently inoperable. The outboard steam line isolation valve closed automatically and the inboard steam line isolation valve was manually closed. The HPCI room carbon dioxide fire protection system actuated due to the high temperature spike. No fire was present. The Reactor Core Isolation Cooling (RCIC) System, Auto Depressurization System (ADS), Low Pressure Core Spray System and Low Pressure Coolant Injection System are operable.
Initial Safety Evaluation - Low initial safety significance due to availability of alternate high and low pressure injection systems. Corrective Actions - HPCI will remain inoperable pending investigation. Determine and correct the cause of HPCI isolation. Determine if the inboard steam isolation valve should have automatically closed. The licensee has notified the NRC Resident Inspector.
Upon further investigation of this event, it has been determined that the malfunction of the HPCI system was due to a condition which was introduced by the maintenance/testing activities while the system was declared inoperable. During the valve restoration/clearance cancellation process performed in support of HPCI system return to service, the 2-E41-F021, HPCI Exhaust Line Check Valve was inadvertently left in the locked closed position. In this configuration turbine exhaust over pressurization occurred resulting in actuation of the turbine exhaust diaphragm high pressure trip, subsequent generation of a Primary Containment Isolation system Division 1 Group 4 isolation signal, closure of the HPCI system outboard steam isolation valve 2-E41-F003, and rupture of the HPCI turbine exhaust rupture disc assembly. An evaluation of the impact of this event was performed and the necessary corrective actions and additional post-maintenance testing completed satisfactorily prior to declaring the HPCI system operable on November 16, 2003, at 2015 EST. After further review of the event and event reporting guidance, this event is not reportable in accordance with 10 CFR 50.72 or 50.73. NUREG-1022, Revision 2 provides clarification of the reporting requirements contained within 10 CFR 50.72 and 50.73. Specifically, in discussions associated with events that could prevent fulfillment of a safety function, NUREG-1022, Revision 2, Section 3.2.7, provides the following example of a condition that is not reportable under these criteria: removal of a system or part of a system from service as part of a planned evolution for maintenance or surveillance testing when done in accordance with an approved procedure and the plant's TS (unless a condition is discovered that could have prevented the system from performing its function) In this case, HPCI was properly removed from service for planned maintenance/testing under TS Limiting Condition for Operation, A2-03-1190, and was not returned to service until HPCI system operability was restored. The intent of the qualifying statement in NUREC-1022 (i.e., unless a condition is discovered that could have prevented the system from performing its function) is to ensure that pre-existing operability concerns that are discovered during maintenance activities are reported. It is not intended to require reporting of conditions, introduced by the maintenance/testing activity that are identified and corrected prior to returning the system to service. In this case, post-maintenance testing performed prior to declaring the HPCI system operable, identified a problem that had been introduced by activities implemented in support of the maintenance activity prior to returning the HPCI system to service and which did not exist at any time when the HPCI system had been relied upon to fulfill its intended safety function. Therefore the licensee is retracting this event. The licensee notified the Resident Inspector The Reg 2 RDO(Brian Bonser) was notified |
| Where | |
|---|---|
Brunswick  North Carolina (NRC Region 2) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
| Time - Person (Reporting Time:+2.08 h0.0867 days <br />0.0124 weeks <br />0.00285 months <br />) | |
| Opened: | P. Dubrouillet 05:27 Nov 13, 2003 |
| NRC Officer: | Gerry Waig |
| Last Updated: | Dec 4, 2003 |
| 40318 - NRC Website | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (96 %) |
| After | Power Operation (96 %) |
Brunswick with 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
WEEKMONTHYEARENS 559972022-07-16T00:20:00016 July 2022 00:20:00
[Table view]10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (HPCI) Inoperable ENS 557802022-03-10T01:13:00010 March 2022 01:13:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (HPCI) Inoperable ENS 541162019-06-13T01:27:00013 June 2019 01:27:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (Hpci) Inoperable ENS 531232017-12-17T08:16:00017 December 2017 08:16:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (Hpci) System Declared Inoperable ENS 527882017-06-05T17:52:0005 June 2017 17:52:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Control Room Air Conditioning and Emergency Ventilation Systems Inoperable ENS 526792017-04-14T04:15:00014 April 2017 04:15:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Drywell and Suppression Chamber Simultaneously Aligned for Venting ENS 520642016-07-05T20:40:0005 July 2016 20:40:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (Hpci) System Declared Inoperable ENS 517692016-03-04T17:35:0004 March 2016 17:35:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Emergency Diesel Generator Declared Inoperable ENS 508162015-02-12T18:36:00012 February 2015 18:36:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Hpci Declared Inoperable During Weekly Inspection ENS 485962012-12-14T18:06:00014 December 2012 18:06:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Control Building Emergency Ventilation System Inoperable for Two Minutes ENS 478932012-05-02T21:58:0002 May 2012 21:58:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection Inoperable Due to Erratic Governor Operation ENS 474932011-12-01T18:44:0001 December 2011 18:44:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Control Room Air Conditioning and Control Room Emergency Ventilation Systems Inoperable ENS 467632011-04-17T02:52:00017 April 2011 02:52:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Hpci Inoperable Due to Lube Oil Pressure Low Out of Band ENS 467402011-04-07T21:40:0007 April 2011 21:40:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Loss of the Control Room Emergency Ventilation System ENS 452642009-08-14T23:58:00014 August 2009 23:58:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Hpci Inoperable Due to Automatic Closure of Inboard Isolation Valve ENS 448102009-01-28T01:07:00028 January 2009 01:07:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Unit 2 Hpci System Inoperable for Two Hours Due to Condensate in Exhaust Line ENS 447932009-01-21T18:00:00021 January 2009 18:00:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Loss of Control Room Air Conditioning and Emergency Ventilation System ENS 447482009-01-01T19:30:0001 January 2009 19:30:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Two Emergency Diesel Generators Declared Inoperable Due to Component Failure ENS 443092008-06-19T21:35:00019 June 2008 21:35:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Control Room Ventilation Inoperable ENS 442622008-06-03T17:13:0003 June 2008 17:13:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Loss of Control Room Emergency Ventillation System for 12 Minutes ENS 441792008-04-30T03:13:00030 April 2008 03:13:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (Hpci) System Inoperable Due to Seal Leak ENS 437112007-10-11T02:45:00011 October 2007 02:45:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Unit 2 Hpci Pump Seal Failure ENS 431972007-02-28T03:26:00028 February 2007 03:26:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (Hpci) Inoperability ENS 429062006-10-13T17:57:00013 October 2006 17:57:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (Hpci) System Declared Inoperable Due to Potential Turbine Exhaust Diaphragm Failure ENS 424882006-04-10T20:30:00010 April 2006 20:30:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Control Room Emergency Ventilation System Declared Inoperable Due to Design Deficiency ENS 423052006-02-03T04:36:0003 February 2006 04:36:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection (Hpci) System Inoperable Due to One Hpci Turbine Exhaust Vacuum Breaker Isolation Valve Failure ENS 422542006-01-12T14:20:00012 January 2006 14:20:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Control Room Air Conditioning and Control Room Emergency Ventilation Systems Inoperable ENS 418952005-08-05T22:40:0005 August 2005 22:40:00 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 Technical Specification Required Shutdown Due to Inoperability of All 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 408332004-06-22T13:00:00022 June 2004 13:00:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Presure Coolant Injection System Inoperable Due to Maintenance ENS 407142004-04-29T02:30:00029 April 2004 02:30:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident Hpci System Inoperable Following Planned Maintenance ENS 406362004-04-03T08:00:0003 April 2004 08:00:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection System Inoperable ENS 403182003-11-13T03:22:00013 November 2003 03:22:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident High Pressure Coolant Injection System Isolation During Testing 2022-07-16T00:20:00 | |