ENS 40714
ENS Event | |
|---|---|
02:30 Apr 29, 2004 | |
| Title | Hpci System Inoperable Following Planned Maintenance |
| Event Description | During post maintenance testing following a High Pressure Coolant Injection (HPCI) System outage, the HPCI System was not declared operable due to unstable operation - oscillations of turbine speed (300-400 RPM), pump flow (600 GPM) and discharge pressure (300-550 psig) were seen in both automatic and manual flow control during the System Operability Periodic Test. HPCI had been declared inoperable at 0410 on 4/28/04 and placed under clearance to support planned maintenance on the Flow Controller, Flow Transmitter, system valves and condensate pump. The cause of the unstable operation is currently being investigated.
The licensee notified the NRC Resident Inspector.
On April 28, 2004, at 0410 hours0.00475 days <br />0.114 hours <br />6.779101e-4 weeks <br />1.56005e-4 months <br />, the High Pressure Coolant Injection (HPCI) system was declared inoperable to support scheduled maintenance on the HPCI system. To satisfy post maintenance test requirements and support restoring the HPCI system to an operable status, surveillance test, OPT-09.2, "HPCI System Operability Test," was performed. During this testing at 2230 hours0.0258 days <br />0.619 hours <br />0.00369 weeks <br />8.48515e-4 months <br />, oscillations in pump flow, pressure, and turbine speed were observed in both the automatic and manual flow control modes of operation. Based on the test results, HPCI remained inoperable until the cause of the oscillations could be identified, corrective actions implemented, and the system satisfactorily tested. On April 29, 2004, at 0140 hours0.00162 days <br />0.0389 hours <br />2.314815e-4 weeks <br />5.327e-5 months <br />, the NRC was conservatively notified (Event Number 40714), in accordance with 10 CPR 50.72(b)(3)(v)(D), of a condition that at the time of discovery could have prevented the fulfillment of the HPCI safety function. Troubleshooting determined that the HPCI flow controller to the 2-E41-C002-CNV Ramp Generator Signal Converter (RGSC) was subject to spurious deviations. The RGSC was removed from its installed position and bench tested. Circuit review and testing determined that electronic component degradation was the most likely cause of the RGSC output signal perturbations. A new RGSC was calibrated and installed. After installation, in place testing showed that the new ramp generator did not exhibit signal variations. A final HPCI system operability test was performed and verified that the HPCI system was responding normally. On May 1, 2004, at 1220 hours0.0141 days <br />0.339 hours <br />0.00202 weeks <br />4.6421e-4 months <br />, the HPC1 system was restored to service. Reportability Discussion: NUREG-1022, Rev. 2, Section 3.2.7 (page 56) lists types of events or conditions that are generally not reportable under 10 CFR 50.72(b)(3)(v) and 10 CFR 50.73(a)(2)(v) criteria. The list of not-reportable conditions includes: 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). On April 28, 2004, the HPCI system was removed from service to support a planned maintenance system outage. In addition, surveillance testing was performed to support system restoration following the maintenance outage for testing in accordance with an approved surveillance procedure. Based on the post maintenance test results, the HPCI system was declared inoperable and since the HPCI system is a single train safety system, an ENS notification was made. However, further evaluation of the condition determined that no condition was discovered that could have prevented the HPCI system from performing its functions. The following information provides the basis for that determination: Review of all applicable operating data collected during HPCI system testing performed from the time of discovery of the oscillation concern indicates that (1) the resulting HPCI speed spikes were in the positive direction and therefore no concern related to the inability of HPCI to provide adequate vessel level makeup existed, (2) the RGSC output perturbations followed a consistent pattern and the magnitude of the associated control problem would not have become more severe for a period longer than the assumed HPCI mission time, and (3) none of the excursions experienced were high enough to cause a system trip at the 5000 plus/minus 100 rpm overspeed trip setpoint. Even if a spurious speed spike resulted in a HPCI overspeed trip, the HPCI overspeed trip is designed to automatically reset and allow the system to ramp back up to operating speed. Given these facts, there was no observed performance that represented a loss of system function. Had HPCI been called upon to inject during the time that the condition resulting in HPCI flow oscillations existed, the system would have met all functional requirements. Carolina Power & Light Company, doing business as Progress Energy Carolinas, Inc., has determined that this event does not meet the 10 CFR 50.72 or 10 CFR 50.73 reporting criteria and the notification for Event Number 40714, is retracted. The resident inspector has been notified. Notified R2 DO (R. Ayres). |
| 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:+-0.83 h-0.0346 days <br />-0.00494 weeks <br />-0.00114 months <br />) | |
| Opened: | Ken Hill 01:40 Apr 29, 2004 |
| NRC Officer: | Rich Laura |
| Last Updated: | May 28, 2004 |
| 40714 - 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 40714\u003C/a\u003E - \u003Ca href=\"/Brunswick\" title=\"Brunswick\"\u003EBrunswick\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EHpci System Inoperable Following Planned Maintenance\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 40714 - Brunswick\n","link":"","lat":33.95840833333333,"lon":-78.00979722222222,"icon":"/w/images/7/75/Duke_Energy_icon.png"}],"imageoverlays":null} | |
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 | |