On January 25, 20:7 at 1836 PST, smoke was detected in the High Pressure Core Spray ( HPCS) System diesel room with no indication of a lire. Immediate recovery actions by Operations personnel included opening the disconnect for the affected motor starter, at which point the smoke dissipated, Investigation of the condition found the motor starter for the Diesel Mixed Air Fan had failed, Prior to the start of the event, the HPCS system had been declared inoperable in accordance with plant Technical Specifications for planned maintenance.
The apparent cause of the motor starter failure was overheating of the contactor coil due to elevated system voltages. Corrective actions for this event include replacement of the contactor coil, increased frequency of preventative maintenance, and procedure revision. There were no other event-related equipment malfunctions.
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Category:Letter
MONTHYEARGO2-24-004, License Amendment Request to Revise Emergency Plan2024-01-30030 January 2024 License Amendment Request to Revise Emergency Plan IR 05000397/20230042024-01-29029 January 2024 Integrated Inspection and Independent Spent Fuel Storage Installation Report 05000397/2023004 and 07200035/2023001 GO2-24-003, Relief Requests for the Columbia Generating Station Fifth Ten-Year Interval Inservice Testing2024-01-29029 January 2024 Relief Requests for the Columbia Generating Station Fifth Ten-Year Interval Inservice Testing ML24011A1522024-01-10010 January 2024 March 2024 Emergency Preparedness Exercise Inspection-Request for Information GO2-24-005, Docket No. 50-397 Supplement to Reply to a Notice of Violation; EA-21-1702024-01-0808 January 2024 Docket No. 50-397 Supplement to Reply to a Notice of Violation; EA-21-170 GO2-23-136, Guarantee of Payment of Deferred Premium2023-12-20020 December 2023 Guarantee of Payment of Deferred Premium GO2-23-135, Notice of Readiness for Supplemental Inspection2023-12-14014 December 2023 Notice of Readiness for Supplemental Inspection GO2-23-130, Reply to a Notice of Violation; EA-23-0542023-12-14014 December 2023 Reply to a Notice of Violation; EA-23-054 GO2-23-105, Licensing Basis Document Update and Biennial Commitment Change Report2023-12-12012 December 2023 Licensing Basis Document Update and Biennial Commitment Change Report ML23288A0002023-12-0707 December 2023 Issuance of Amendment No. 272 to Adopt TSTF-541, Revision 2, Add Exceptions to Surveillance Requirements for Valves and Dampers Locked in the Actuated Position GO2-23-107, Application to Revise Technical Specifications to Adopt TSTS-584, Eliminate Automatic RWCU System Isolation on SLC Initiation2023-12-0505 December 2023 Application to Revise Technical Specifications to Adopt TSTS-584, Eliminate Automatic RWCU System Isolation on SLC Initiation GO2-23-126, Docket No. 50-397 Voluntary Response to Regulatory Issue Summary 2023-012023-11-28028 November 2023 Docket No. 50-397 Voluntary Response to Regulatory Issue Summary 2023-01 GO2-23-121, Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation2023-11-27027 November 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation IR 05000397/20230122023-11-20020 November 2023 Commercial Grade Dedication Inspection Report 05000397/2023012 ML23311A2082023-11-0909 November 2023 Reassignment of U.S. Nuclear Regulatory Commission Branch Chief in the Division of Operating Reactor Licensing for Plant Licensing Branch IV IR 05000397/20230102023-11-0909 November 2023 Biennial Problem Identification and Resolution Inspection Report 05000397/2023010 IR 05000397/20230932023-11-0101 November 2023 Final Significance Determination of a White Finding, Notice of Violation and Follow-Up Assessment Letter; NRC Inspection Report 05000397/2023093 ML23299A2072023-10-26026 October 2023 Biennial Requalification Inspection Request for Information IR 05000397/20230032023-10-25025 October 2023 Integrated Inspection Report 05000397/2023003 IR 05000397/20230112023-10-0404 October 2023 License Renewal Phase 2 Report 05000397/2023011 IR 05000397/20234012023-09-11011 September 2023 Security Baseline Inspection Report 05000397/2023401 GO2-23-097, In-Service Inspection Summary Report for the Twenty-Sixth Refueling Outage (R26)2023-09-0606 September 2023 In-Service Inspection Summary Report for the Twenty-Sixth Refueling Outage (R26) ML24032A2182023-09-0101 September 2023 Information Request, Security IR 2024401 GO2-23-100, Technical Specification Section 5.6.4 Post Accident Monitoring Instrumentation 14-Day Report for Inoperable Suppression Pool Level Indication2023-08-31031 August 2023 Technical Specification Section 5.6.4 Post Accident Monitoring Instrumentation 14-Day Report for Inoperable Suppression Pool Level Indication GO2-23-056, Application to Revise Technical Specifications to Adopt TSTF-230, Add New Condition B to LCO 3.6.2.3, RHR Suppression Pool Cooling2023-08-29029 August 2023 Application to Revise Technical Specifications to Adopt TSTF-230, Add New Condition B to LCO 3.6.2.3, RHR Suppression Pool Cooling IR 05000397/20230052023-08-22022 August 2023 Updated Inspection Plan for Columbia Generating Station (Report 05000397/2023005) - Mid Year Letter IR 05000397/20230022023-08-0101 August 2023 Integrated Inspection Report 05000397/2023002 GO2-23-093, Supplement to Reply to a Notice of Violation: EA-21-1702023-07-27027 July 2023 Supplement to Reply to a Notice of Violation: EA-21-170 ML23206A2442023-07-25025 July 2023 Energy Northwest Columbia Generating Station, Response to Apparent Violation in NRC Inspection Report 05000397/2023092; EA-23-054 GO2-23-068, Notification of Completion of Commitments Required Prior to Entry Into the Period of Extended Operation2023-07-19019 July 2023 Notification of Completion of Commitments Required Prior to Entry Into the Period of Extended Operation GO2-23-090, Reply to a Notice of Violation2023-07-12012 July 2023 Reply to a Notice of Violation ML23143A1202023-06-27027 June 2023 Request Number 4ISI-11 to the American Society of Mechanical Engineers Boiler and Pressure Vessel Code Regarding Alternate Examination of Reactor Vessel Welds GO2-23-073, Notification of NPDES Permit Issuance2023-06-26026 June 2023 Notification of NPDES Permit Issuance ML23163A2502023-06-12012 June 2023 Summary of Changes and Analysis for Revision 41 of Plant Procedures Manual 13.8.1 Emergency Dose Projection System Operations GO2-23-072, Cycle 27 Core Operating Limits Report2023-06-0505 June 2023 Cycle 27 Core Operating Limits Report ML23157A2702023-06-0101 June 2023 4-2022-011 -022 Letter - OI Closure to Licensee IR 05000397/20230922023-06-0101 June 2023 NRC Inspection Report 05000397/2023092 and Preliminary White Finding IR 05000397/20230902023-06-0101 June 2023 Final Significance Determination of a White Finding, Notice of Violation and Follow-Up Assessment Letter; NRC Inspection Report 05000397/2023090 GO2-23-055, Independent Spent Fuel Storage Installation, 2022 Annual Radiological Environmental Operating Report2023-05-15015 May 2023 Independent Spent Fuel Storage Installation, 2022 Annual Radiological Environmental Operating Report IR 05000397/20230012023-05-0505 May 2023 Integrated Inspection Report 05000397/2023001 - April 26, 2023 GO2-23-006, License Amendment Request to Clean-Up Operating License and Appendix a Technical Specifications2023-05-0101 May 2023 License Amendment Request to Clean-Up Operating License and Appendix a Technical Specifications IR 05000397/20233012023-05-0101 May 2023 NRC Examination Report 05000397/2023301 GO2-23-053, 2022 Annual Environmental Operating Report2023-04-26026 April 2023 2022 Annual Environmental Operating Report GO2-23-057, 2022 Annual Radioactive Effluent Release Report2023-04-25025 April 2023 2022 Annual Radioactive Effluent Release Report ML23110A2642023-04-20020 April 2023 Request for Information License Renewal Phase 2 Inspection GO2-23-012, Application to Revise Technical Specifications to Adopt Tstf-541, Add Exceptions to Surveillance Requirements for Valves and Dampers Locked in the Actuated Position2023-03-27027 March 2023 Application to Revise Technical Specifications to Adopt Tstf-541, Add Exceptions to Surveillance Requirements for Valves and Dampers Locked in the Actuated Position GO2-23-041, Generation Station - Level of Financial Protection - Annual Reporting Requirement2023-03-15015 March 2023 Generation Station - Level of Financial Protection - Annual Reporting Requirement GO2-23-038, Plant Decommissioning Fund Status Report2023-03-15015 March 2023 Plant Decommissioning Fund Status Report ML23013A0812023-03-15015 March 2023 Issuance of Amendment No. 270 Revision to Technical Specifications to Adopt TSTF 505, Revision 2, Provide Risk-Informed Extended Completion Times-RITSTF Initiative 4B GO2-23-034, Report of Changes or Errors in Emergency Core Cooling System Loss of Coolant Accident Analysis Models Pursuant to 10 CFR 50.462023-03-13013 March 2023 Report of Changes or Errors in Emergency Core Cooling System Loss of Coolant Accident Analysis Models Pursuant to 10 CFR 50.46 2024-01-08
[Table view] Category:Licensee Event Report (LER)
MONTHYEAR05000397/LER-2017-0072017-11-30030 November 2017 Valve Closure Results in Momentary Increase in Secondary Containment Pressure, LER 17-007-00 for Columbia Generating Station Regarding Valve Closure Results in Momentary Increase in Secondary Containment Pressure 05000397/LER-2017-0062017-11-0909 November 2017 CONDITION PROHIBITED BY TECHNICAL SPECIFICATIONS DUE TO INCOMPLETE ACTION STATEMENT, LER 17-006-00 for Columbia Generating Station for Condition Prohibited by Technical Specifications Due to Incomplete Action Statement 05000397/LER-2017-0052017-11-0909 November 2017 Valve Closure Results in Momentary Increase in Secondary Containment Pressure, LER 17-005-00 for Columbia Generating Station Regarding Valve Closure Results in Momentary Increase in Secondary Containment Pressure 05000397/LER-2017-0042017-10-18018 October 2017 MANUAL REACTOR SCRAM DUE TO HIGH MAIN CONDENSER BACK PRESSURE, LER 17-004-00 for Columbia Generating Station Regarding Manual Reactor Scram Due to High Main Condenser Back Pressure 05000397/LER-2016-0022017-09-27027 September 2017 1 OF 3, LER 16-002-01 for Columbia Generating Station Regarding Valve Closure Results in Momentary Increase in Secondary Containment Pressure 05000397/LER-2016-0032017-08-29029 August 2017 Failure of Fan to Start Results in Momentary Increase in Secondary Containment Pressure, LER 16-003-01 for Columbia Regarding Failure of Fan to Start Results in Momentary Increase in Secondary Containment Pressure 05000397/LER-2017-0032017-08-24024 August 2017 Momentary loss of Secondary Containment due to Weather, LER 17-003-00 for Columbia Generating Station Regarding Momentary Loss of Secondary Containment due to Weather 05000397/LER-2017-0022017-07-10010 July 2017 Implementation of Enforcement Guidance Memorandum 11-003, Revision 3, LER 17-002-00 for Columbia Generating Station re Implementation of Enforcement Guidance Memorandum 11-003, Revision 3 05000397/LER-2016-0042017-06-0808 June 2017 1 OF 3, LER 16-004-01 for Columbia Generating Station Regarding Automatic Scram Due to Off-site Load Reject 05000397/LER-2017-0012017-03-20020 March 2017 Contactor Coil Failure Results in Tripping of HPCS Diesel Mixed Air Fan, LER 17-001-00 for Columbia Generating Station Regarding Contactor Coil Failure Results in Tripping of HPCS Diesel Mixed Air Fan 05000397/LER-2016-0052017-02-15015 February 2017 Leak in Minimum Flow Line Makes HPCS and Primary Containment Inoperable, LER 16-005-00 for Columbia Generating Station Regarding Leak in Minimum Flow Line Makes HPCS and Primary Containment Inoperable 05000397/LER-2016-0012016-05-24024 May 2016 MANUAL REACTOR SCRAM FOLLOWING LOSS OF REACTOR CLOSED COOLING, LER 16-001-00 for Columbia Regarding Manual Reactor Scram Following Loss of Reactor Closed Cooling 05000397/LER-2015-0072016-01-0707 January 2016 REACTOR BUILDING PRESSURE GREATER THAN TECHNICAL SPECIFICATIONS REQUIREMENT, LER 15-007-00 for Columbia Regarding Reactor Building Pressure Greater Than Technical Specifications Requirement 2017-09-27
[Table view] |
comments regarding burden estimate to the FOLA, Privacy and Information CoPections Branch (T5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001 or by e-mai to used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection 05000- NUMBER NO.
001 00 Columbia Generating Station 397 2017 - -
Plant Conditions
At the time of the event, the plant was operating in Mode 1 at 100% power. There were no structures, systems, or components that were inoperable at the start of the event that contributed to the event.
Event Description
On January 25, 2017 at 1836 PST, with the High Pressure Core Spray (HPCS) System [BG] declared inoperable in accordance with plant Technical Specifications for planned maintenance, the Diesel Mixed Air (DMA) Fan [FAN] was in normal operation with the fan running continuously, supplying air to the HPCS diesel room. The control room received a loss of power alarm for the fan's motor starter [MSTR], which was then followed by notification of smoke in the HPCS diesel room. The Operator at the motor control center [MCC] for the motor starter opened the disconnect and the smoke dissipated. Inspection of the motor starter found that the contactor coil [CNTR] had overheated.
This event is reportable as an event that could have prevented fulfillment of safety functions needed to mitigate the consequences of an accident per 10 CFR 50.73(a)(2)(v)(D), should the HPCS diesel have received a start signal during a design basis event. This condition was reported under 10 CFR 50.72(b)(3)(v)(D) via Event Notification #52510 for an event or condition that, at the time of discovery, could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident; however, the Event Notification was retracted on February 3, 2017, based on the determination that the HPCS System had been declared inoperable prior to the smoke incident in accordance with plant Technical Specifications.
Immediate Corrective Actions
Operations personnel opened the disconnect for the affected motor starter, at which point the smoke dissipated.
Assessment of Safety Consequences
There were no actual safety consequences associated with this event, as there was no loss of safety function. There was no change in plant status or operating condition, and there was no risk to the public at any time due to this event. At the time of the event, work on the HPCS Service Water System was being performed in accordance with 10 CFR 50.65(a)(4) for managing risk. In emergency conditions, the HPCS System is used to provide core cooling and, during a loss of coolant accident, maintains reactor inventory. The DMA fan maintains suitable temperatures within the HPCS diesel generator room to ensure equipment operability temperature limits are not exceeded during an emergency. Had the HPCS System been in service and credited for accident mitigation, this event could have challenged the ability of the HPCS System to perform its safety function.
Cause of Event
The investigation into the apparent cause of the unexpected fan failure determined that the contactor coil for the fan's motor starter had overheated. The cause evaluation determined that the premature coil failure was likely caused by two contributing factors: increased coil operating currents and heating caused by elevated system voltages, and increased heating of the coil assembly caused by high magnet assembly temperatures due to loose shading coils.
Est mated burden per response to comply with th s mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons teamed are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the FOIA Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person Is not required to respond to, the information collection.
05000- NUMBER NO.
.001 00 Columbia Generating Station 397 2017 - Similar Events A review of Corrective Action Program documents did not identify any previous starter coil failures for this particular manufacturer. Similar equipment from a different manufacturer recently experienced coil failures; Energy Northwest is working to identify the cause and develop a corrective action plan. Neither of the previous coil failures in the equipment has resulted in a loss of safety function or required an LER.
Further Corrective Actions The contactor coil, magnet assembly, and upper contactor assembly were replaced. The starter was retested and returned to service. For critical starters from this manufacturer the frequency of the inspection maintenance will increase, and plant procedures w;11 be revised to ensure adequate inspection of all magnet assemblies and coils.
Energy Industry Identification System (EDS) Information codes from IEEE Standards 805-1984 and 803-1983 are represented in brackets as [XX] and [XXX] throughout the body of the narrative.
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05000397/LER-2017-001 | Contactor Coil Failure Results in Tripping of HPCS Diesel Mixed Air Fan LER 17-001-00 for Columbia Generating Station Regarding Contactor Coil Failure Results in Tripping of HPCS Diesel Mixed Air Fan | 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000397/LER-2017-002 | Implementation of Enforcement Guidance Memorandum 11-003, Revision 3 LER 17-002-00 for Columbia Generating Station re Implementation of Enforcement Guidance Memorandum 11-003, Revision 3 | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000397/LER-2017-003 | Momentary loss of Secondary Containment due to Weather LER 17-003-00 for Columbia Generating Station Regarding Momentary Loss of Secondary Containment due to Weather | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000397/LER-2017-004 | MANUAL REACTOR SCRAM DUE TO HIGH MAIN CONDENSER BACK PRESSURE LER 17-004-00 for Columbia Generating Station Regarding Manual Reactor Scram Due to High Main Condenser Back Pressure | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000397/LER-2017-005 | Valve Closure Results in Momentary Increase in Secondary Containment Pressure LER 17-005-00 for Columbia Generating Station Regarding Valve Closure Results in Momentary Increase in Secondary Containment Pressure | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | 05000397/LER-2017-006 | CONDITION PROHIBITED BY TECHNICAL SPECIFICATIONS DUE TO INCOMPLETE ACTION STATEMENT LER 17-006-00 for Columbia Generating Station for Condition Prohibited by Technical Specifications Due to Incomplete Action Statement | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | 05000397/LER-2017-007 | Valve Closure Results in Momentary Increase in Secondary Containment Pressure LER 17-007-00 for Columbia Generating Station Regarding Valve Closure Results in Momentary Increase in Secondary Containment Pressure | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material 10 CFR 50.73(a)(2)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident |
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