10-27-2016 | Entergy manually shutdown the Grand Gulf Nuclear Station ( GGNS) reactor on September 8, 2016, at approximately 1104 hours0.0128 days <br />0.307 hours <br />0.00183 weeks <br />4.20072e-4 months <br />, to replace Residual Heat Removal ( RHR) Pump 'A' after it failed its technical specification surveillance. The reactor entered MODE 4, Cold Shutdown, at approximately 0509 hours0.00589 days <br />0.141 hours <br />8.416005e-4 weeks <br />1.936745e-4 months <br /> on September 9, 2016. Residual Heat Removal Train 'B' was placed in shutdown cooling mode ( SDC) to maintain Reactor coolant temperature 110 degrees Fahrenheit (F) to 120 F on September 9, 2016 at 0332. At the time of entry into MODE 4, and throughout the time period the 'A' RHR pump was inoperable, the Alternate Decay Heat Removal ( ADHR) System was not available because the ADHR heat exchangers tube-side cooling water system had been clearance-tagged CLOSED to support cleaning of the heat exchanger tubes since August 10, 2016. This condition was not identified until September 23, 2016, after the 'A' RHR train was returned to OPERABLE status. The direct cause of this event appears to be the lack of adequate information validation and verification by station personnel. Entergy personnel verified both RHR trains were operable and available on September 23, 2016,
- when the ADHR Heat Exchangers were identified as clearance-tagged CLOSED. The cause of the event remains under investigation and this licensee event report will be supplemented upon completion of the causal evaluation.
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Category:Letter
MONTHYEARML24012A1422024-01-31031 January 2024 Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0051 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting)) IR 05000416/20230042024-01-25025 January 2024 Integrated Inspection Report 5000416/2023004 ML24018A0222024-01-18018 January 2024 Core Operating Limits Report (COLR) Cycle 24, Revision 2 IR 05000416/20243012024-01-16016 January 2024 NRC Initial Operator Licensing Examination Approval 05000416/2024301 ML24012A1962024-01-12012 January 2024 Response to 2nd Round Request for Additional Information Concerning Relief Request Number EN-RR-22-001 Proposed Alternative to Use ASME Code Case N-752, Risk-Informed Categorization and ML23349A1672023-12-21021 December 2023 Request for Withholding Information from Public Disclosure ML23348A3572023-12-14014 December 2023 Application to Revise Technical Specifications to Use Online Monitoring Methodology Slides and Affidavit for Pre-Submittal Meeting ML23348A3712023-12-14014 December 2023 Notification of an NRC Fire Protection Baseline Inspection (NRC Inspection Report (05000416/2024011) and Request for Information ML23340A2222023-12-13013 December 2023 Project Manager Assignment ML23352A0292023-12-13013 December 2023 Entergy - 2024 Nuclear Energy Liability Evidence of Financial Protection ML23340A1592023-12-13013 December 2023 Entergy Operations, Inc. - Entergy Fleet Project Manager Assignment ML23333A1362023-11-29029 November 2023 Supplement to Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation ML23325A1422023-11-21021 November 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation IR 05000416/20234032023-11-13013 November 2023 Security Baseline Inspection Report 05000416/2023403 Cover Letter 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 05000416/20230032023-11-0808 November 2023 Integrated Inspection Report 05000416/2023003 ML23270B9932023-09-29029 September 2023 Request to Update ASME Boiler & Pressure Vessel Code Relief Request SE with NRC-Approved Revision of Bwrip Guidelines (GG-ISI-020 & RBS-ISI-019) (EPID L-2022-LLR-0090) - Non-Proprietary ML23270B1892023-09-27027 September 2023 Evacuation Time Estimate Study ML23269A1242023-09-27027 September 2023 Request for Withholding Information from Public Disclosure ML23240A3952023-08-28028 August 2023 Reply to a Notice of Violation; EA-23-019 IR 05000416/20230052023-08-21021 August 2023 Updated Inspection Plan for Grand Gulf Nuclear Station (Report 05000416/2023005) ML23226A1002023-08-18018 August 2023 Regulatory Audit in Support of License Amendment Requests to Adopt TSTF-505, Revision 2, and 10 CFR 50.69 IR 05000416/20230022023-08-0808 August 2023 Integrated Inspection Report 05000416/2023002 and Independent Spent Fuel Storage Installation Inspection Report 07200050/2023001 IR 05000416/20234042023-08-0707 August 2023 Material Control and Accounting Program Inspection Report 05000416/2023404 IR 05000416/20230912023-07-28028 July 2023 Final Significance Determination of a Green Finding and Notice of Violation; NRC Inspection Report 05000416/2023091 ML23208A2112023-07-27027 July 2023 Entergy Operations Inc., Application to Revise Technical Specifications to Adopt TSTF-205, Revision of Channel Calibration, Channel Functional Test, and Related Definitions ML23166B0712023-06-15015 June 2023 Reply to Notice of Violation EA-22-104 and EA-22-115 ML23166B0662023-06-15015 June 2023 Response to NRC Integrated Inspection Report 05000416/2023001 ML23159A2302023-06-0808 June 2023 Response to Request for Additional Information Concerning Request to Update ASME Code Relief Request Safety Evaluations with NRC-Approved Revision of BWRVIP Guidelines (GG-ISI-020, and RBS-ISI-019) GNRO-2023/00014, License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b2023-06-0606 June 2023 License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b GNRO-2023/00015, Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors2023-06-0606 June 2023 Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors ML23122A1632023-05-18018 May 2023 NRC Inspection Report 05000416/2023090 and Preliminary White Finding IR 05000416/20234022023-05-17017 May 2023 Security Baseline Inspection Report 05000416/2023402 ML23110A8002023-05-10010 May 2023 Notice of Violation; Integrated Inspection Report 05000416/2023001 and NRC Investigation Report 4-2022-004 ML23130A2732023-05-10010 May 2023 and Waterford 3 Steam Electric Station - Response to Regulatory Issue Summary 2023-01, Preparation and Scheduling of Operator Licensing Examinations IR 05000416/20230012023-05-10010 May 2023 Notice of Violation; Integrated Inspection Report 05000416/2023001 and NRC Investigation Report 4-2022-004 ML23117A2172023-05-0101 May 2023 Safety Evaluation for Quality Assurance Program Manual Reduction in Commitment ML23117A0422023-04-27027 April 2023 Annual Radioactive Effluent Release Report (ARERR) ML23111A2132023-04-21021 April 2023 Responses to RAI Concerning Relief Request Number EN-RR-22-001 Proposed Alternative to Use ASME Code Case N-752, Risk-Informed Categorization and Treatment for Repair/ Replacement Activities ML23110A1122023-04-20020 April 2023 Annual Report for Entergy Quality Assurance Program Manual Changes Under 10 CFR 50.54(a)(3), 10 CFR 71.106, and 10 CFR 72.140(d). Notification of Application of Approved Appendix B to 10 CFR 72 Subpart G ML23110A0552023-04-20020 April 2023 Annual Radiological Environmental Operating Report (AREOR) ML23103A1022023-04-13013 April 2023 Annual Report of Individual Monitoring - NRC Form 5 for 2022 Per 10 CFR 20.2206 ML23102A1482023-04-12012 April 2023 Notification of NRC Initial Operator Licensing Examination 05000416/2024301 ML23089A0602023-03-30030 March 2023 Entergy Operations, Inc. - Fleet Project Manager Assignment ML23088A3922023-03-29029 March 2023 Nuclear Onsite Property Damage Insurance (10 CFR 50.54(w)(3)) ML23079A2772023-03-21021 March 2023 U.S. Nuclear Regulatory Commission Presentation at the May 1, 2023, Port Gibson City Council Meeting ML23080A2882023-03-21021 March 2023 Decommissioning Funding Status Report Per 10 CFR 50.75(f)(1) Entergy Operations, Inc IR 05000416/20230112023-03-0808 March 2023 Design Basis Assurance Inspection Report 05000416/2023011 2024-01-31
[Table view] Category:Licensee Event Report (LER)
MONTHYEAR05000416/LER-2016-0092017-08-16016 August 2017 Entry into Mode of Applicability with the Oscillation Power Range Monitor Upscale Settings Incorrectly Set, LER 16-009-01 for Grand Gulf, Unit 1, Regarding Entry into Mode of Applicability with the OPRM Upscale Settings Incorrectly Set 05000416/LER-2016-0082017-08-16016 August 2017 Entry into Mode of Applicability with the Alternate Decay Heat Removal System Inoperable, LER 16-008-001 for Grand Gulf, Unit 1, Regarding Entry into Mode of Applicability with the Alternate Decay Heat Removal System Inoperable 05000416/LER-2017-0012017-03-28028 March 2017 High Pressure Core Spray (HPCS) Jockey Pump Trip, LER 17-001-00 for Grand Gulf, Unit 1, Regarding High Pressure Core Spray Jockey Pump Trip 05000416/LER-2016-0012016-05-16016 May 2016 Valid Engineered Safety Feature Actuation and Temporary Loss of Residual Heat Removal, LER 16-001-00 for Grand Gulf, Unit 1, Regarding Valid Engineered Safety Feature Actuation and Temporary Loss of Residual Heat Removal GNRO-2014/00049, Report Pursuant to 10 CFR 71.95 (a)(3) and (B) of Seven Potential Instances of Noncompliance with Certificate of Compliance No. 9233 for TN-RAM Package, Revision 112014-07-31031 July 2014 Report Pursuant to 10 CFR 71.95 (a)(3) and (B) of Seven Potential Instances of Noncompliance with Certificate of Compliance No. 9233 for TN-RAM Package, Revision 11 ML12157A1822012-05-23023 May 2012 Attachment 9 to GNRO-2012/00039 - Entergy Nuclear Grand Gulf Nuclear Station License Renewal Environmental Audit - Hydrology Patton - Attachment L Labeled Reporting Documentation - Unit 2 Sumps. ML0627100452005-08-22022 August 2005 Final Precursor Analysis - Grand Gulf, Unit 1 2017-08-16
[Table view] |
Reported lessons learned 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 Infocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means 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.
PLANT CONDITIONS PRIOR TO THE EVENT
MODE 4 'A' RHR Pump inoperable 'B' RHR Pump in service providing shutdown cooling Alternate Decay Heat Removal System inoperable
DESCRIPTION
Entergy manually shutdown the Grand Gulf Nuclear Station (GGNS) reactor on September 8, 2016, at approximately 1104 hours0.0128 days <br />0.307 hours <br />0.00183 weeks <br />4.20072e-4 months <br />, to replace Residual Heat Removal (RHR) [BO] Pump 'A' after it failed its technical specification surveillance. The reactor entered MODE 4, Cold Shutdown, at approximately 0509 hours0.00589 days <br />0.141 hours <br />8.416005e-4 weeks <br />1.936745e-4 months <br /> on September 9, 2016. Residual Heat Removal Train 'B' was placed in shutdown cooling mode (SDC) to maintain Reactor coolant temperature 110 degrees Fahrenheit (F) to 120 F. At approximately 1742 hours0.0202 days <br />0.484 hours <br />0.00288 weeks <br />6.62831e-4 months <br /> on September 9, 2016, The Alternate Decay Heat Removal (ADHR) [BO] System was placed into standby.
Grand Gulf Nuclear Station Technical Specification (TS) 3.4.10, Residual heat Removal (RHR) Shutdown Cooling System — Cold Shutdown, requires two trains of RHR to be OPERABLE. Condition A, One or two RHR shutdown cooling subsystems inoperable requires the verification of an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem. This action is required to be completed within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter during the mode of applicability.
At the time of entry into MODE 4, and throughout the time period the 'A' RHR pump was inoperable, the ADHR System was not available because the ADHR heat exchangers tube-side cooling water system had been clearance-tagged closed to support cleaning of the heat exchanger tubes since August 10, 2016.
This condition was not identified until September 23, 2016, after the 'A' RHR train was returned to OPERABLE status.
Alternate Decay Heat Removal Background Information:
The ADHR System provides an alternate method of reactor decay heat removal during cold shutdown and refueling conditions. It is designed for use during MODEs 4 and 5 to provide decay heat removal when maintenance is being performed on RHR shutdown cooling loops or associated support systems. An alternative method of decay heat removal must be demonstrated for each required RHR SDC loop that is inoperable. The cause of the event is under investigation and this licensee event report will be supplemented upon completion of the causal evaluation. The direct cause of this event appears to be the lack The ADHR System is an auxiliary cooling loop included as part of the RHR System with separate pumps, heat exchangers, and controls. The ADHR System is completely isolated mechanically and electrically from connected plant systems during MODEs 1, 2, and 3. The functional design basis for the ADHR System is to maintain Reactor coolant temperatures below TS limits during cold shutdown and refueling operations, accomplishing this task by operating in either a Reactor to Reactor cooling mode or Spent Fuel Pool to Reactor cooling mode.
The ADHR pumps and heat exchangers are located in RHR 'C' Pump Room. Cooling water for the ADHR he'at exchangers is supplied by the Plant Service Water (PSW) System.
Grand Gulf Nuclear Station Unit 1 05000-416 Reported lessons learned 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 Infocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means 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.
Two identical ADHR pumps provide the needed head to pump water at a maximum combined flow of 3600 gpm when operated in parallel.
Two ADHR heat exchangers, also located in the RHR "C" Pump Room are operated in a parallel arrangement to provide the required decay heat removal. Each heat exchanger is a horizontally mounted, 50% capacity, two-pass, U-tube type heat exchanger with a single-pass shell. Plant Service Water passes through the tubes, while the water being cooled passes through the shell.
Plant Service Water provides the cooling source to the ADHR System heat exchangers and the ADHR System Air Conditioning Unit. A loss of PSW would prevent the ADHR System from performing its intended function.
REPORTABILITY
CAUSE
The cause of the event is under investigation and this licensee event report (LER) will be supplemented upon completion of the causal evaluation. The direct cause of this event appears to be the lack of adequate information validation and verification by station personnel.
CORRECTIVE ACTIONS
Entergy personnel verified both RHR trains were operable and available on September 23, 2016, when the ADHR Heat Exchangers were identified as clearance-tagged CLOSED.
Entergy established a causal evaluation to determine the cause and to establish corrective actions as appropriate. This LER will be supplemented upon completion of this causal evaluation.
SAFETY SIGNIFICANCE
There were no actual nuclear safety consequences or radiological consequences during the event. The `B' RHR train remained OPERABLE and in service, maintaining shutdown cooling throughout the duration of the event.
PREVIOUS SIMILAR EVENTS
Reactor Steam Dome High Pressure Interlock For Residual Heat Removal System Isolation Resulting In A Technical Specification 3.4.11 RCS Pressure And Temperature (PFF) Limits Violation Resulting In A Technical Specification 3.4.11 RCS Pressure And Temperature (PFF) Limits Violation Entergy has reviewed the above identified licensee event reports and has concluded that the causes and corrective actions associated with these licensee event reports could not have prevented the occurrence of the event documented in this licensee event report.
Grand Gulf Nuclear Station Unit 1 05000-416
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05000416/LER-2016-001 | Valid Engineered Safety Feature Actuation and Temporary Loss of Residual Heat Removal LER 16-001-00 for Grand Gulf, Unit 1, Regarding Valid Engineered Safety Feature Actuation and Temporary Loss of Residual Heat Removal | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat | 05000416/LER-2016-002 | Automatic Actuation of the Reactor Protection System due to 'B' Main Transformer Wiring | | 05000416/LER-2016-003 | Loss of Secondary Containment Safety Function During Routine Roof Inspection | 10 CFR 50.73(a)(2)(v)(C), Loss of Safety Function - Release of Radioactive Material | 05000416/LER-2016-004 | Automatic Reactor SCRAM during Turbine Stop and Control Valve Surveillance | | 05000416/LER-2016-005 | Automatic Reactor SCRAM | | 05000416/LER-2016-006 | Multiple Valid Engineered Safety Feature Actuations | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | 05000416/LER-2016-007 | Technical Specification Shutdown due to Loss of Residual Heat Removal Pump | 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown | 05000416/LER-2016-008 | Entry into Mode of Applicability with the Alternate Decay Heat Removal System Inoperable LER 16-008-001 for Grand Gulf, Unit 1, Regarding Entry into Mode of Applicability with the Alternate Decay Heat Removal System Inoperable | | 05000416/LER-2016-009 | Entry into Mode of Applicability with the Oscillation Power Range Monitor Upscale Settings Incorrectly Set LER 16-009-01 for Grand Gulf, Unit 1, Regarding Entry into Mode of Applicability with the OPRM Upscale Settings Incorrectly Set | 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
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