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On 11/20/2016 at approximately 0342 EST, an automatic reactor SCRAM occurred at 92% power due to Average Power Range Monitor ( APRM) high flux. Oscillations of the turbine control valves and bypass valves were experienced during planned testing of the Turbine Master Trip Solenoid Valve at 95% power. Power was reduced from 95% to 92% by the Main Control Room Operators in an effort to stop the observed oscillations. The control valves did not respond properly during the power reduction, leading to an unexpected rise in reactor pressure and the subsequent scram on high flux.
There were no safety consequences impacting the plant or public safety as a result of this event. All control rods fully inserted and the plant response was as expected. This event is being reported pursuant to 10CFR50.73(a)(2)(iv)(A) due to an actuation of the Reactor Protection System ( RPS). |
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Category:Letter
MONTHYEARML23342A1162024-01-0909 January 2024 Independent Spent Fuel Storage Installation Security Inspection Plan L-23-019, Proof of Financial Protection 10 CFR 140.152023-12-18018 December 2023 Proof of Financial Protection 10 CFR 140.15 IR 05000219/20230022023-11-0909 November 2023 EA-23-076 Oyster Creek Nuclear Generating Station - Notice of Violation and Proposed Imposition of Civil Penalty - $43,750 - NRC Inspection Report No. 05000219/2023002 ML23286A1552023-10-13013 October 2023 Defueled Safety Analysis Report (DSAR) ML23249A1212023-09-0606 September 2023 NRC Inspection Report 05000219/2023002, Apparent Violation (EA-23-076) ML23242A1162023-08-30030 August 2023 Biennial 10 CFR 50.59 and 10 CFR 72.48 Change Summary Report January 1, 2021 Through December 31, 2022 ML23214A2472023-08-22022 August 2023 NRC Inspection Report 05000219/2023002 IR 05000219/20230012023-05-31031 May 2023 NRC Inspection Report No. 05000219/2023001 IR 07200015/20234012023-05-16016 May 2023 NRC Independent Spent Fuel Storage Installation Security Inspection Report 07200015/2023401 ML23114A0912023-04-24024 April 2023 Annual Radioactive Effluent Release Report for 2022 ML23114A0872023-04-24024 April 2023 Annual Radioactive Environmental Operating Report for 2022 L-23-004, HDI Annual Occupational Radiation Exposure Data Reports - 20222023-04-24024 April 2023 HDI Annual Occupational Radiation Exposure Data Reports - 2022 L-23-003, Report on Status of Decommissioning Funding for Reactors and Independent Spent Fuel Storage Installations2023-03-31031 March 2023 Report on Status of Decommissioning Funding for Reactors and Independent Spent Fuel Storage Installations ML23088A0382023-03-29029 March 2023 Stations 1, 2, & 3, Palisades Nuclear Plant, and Big Rock Point - Nuclear Onsite Property Damage Insurance ML22361A1022023-02-24024 February 2023 Reactor Decommissioning Branch Project Management Changes for Some Decommissioning Facilities and Establishment of Backup Project Manager for All Decommissioning Facilities IR 05000219/20220022023-02-0909 February 2023 NRC Inspection Report No. 05000219/2022002 ML23031A3012023-02-0808 February 2023 Discontinuation of Radiological Effluent Monitoring Location in the Sewerage System ML23033A5052023-02-0202 February 2023 First Use Notification of NRC Approved Cask RT-100 ML23025A0112023-01-24024 January 2023 LLRW Late Shipment Investigation Report Per 10 CFR 20, Appendix G ML22347A2732022-12-21021 December 2022 Independent Spent Fuel Storage Installation Security Inspection Plan Dated December 21, 2022 ML22297A1432022-12-15015 December 2022 Part 20 App G Exemption Letter L-22-042, Oyster, Pilgrim, Indian Point, Palisades and Big Rock Point - Proof of Financial Protection 10 CFR 140.152022-12-14014 December 2022 Oyster, Pilgrim, Indian Point, Palisades and Big Rock Point - Proof of Financial Protection 10 CFR 140.15 IR 07200015/20224012022-12-0606 December 2022 NRC Independent Spent Fuel Storage Installation Security Inspection Report 07200015/2022401 (Letter & Enclosure 1) ML22280A0762022-11-0202 November 2022 Us NRC Analysis of Holtec Decommissioning Internationals Funding Status Report for Oyster Creek, Indian Point and Pilgrim Nuclear Power Station ML22276A1762022-10-24024 October 2022 Decommissioning International Proposed Revisions to the Quality Assurance Program Approval Forms for Radioactive Material Packages ML22286A1402022-10-13013 October 2022 NRC Confirmatory Order EA-21-041 IR 05000219/20220012022-08-11011 August 2022 NRC Inspection Report 05000219/2022001 ML22215A1772022-08-0303 August 2022 Decommissioning International (HDI) Proposed Revisions to the Quality Assurance Program Approval Forms for Radioactive Material Packages ML22214A1732022-08-0202 August 2022 Request for Exemption from 10 CFR 20, Appendix G, Section Iii.E ML22207B8382022-07-26026 July 2022 NRC Confirmatory Order EA-21-041 ML22130A6882022-05-10010 May 2022 Late LLRW Shipment Investigation Report Pursuant to 10 CFR 20, Appendix G L-22-026, Occupational Radiation Exposure Data Report - 20212022-04-29029 April 2022 Occupational Radiation Exposure Data Report - 2021 ML22118A6122022-04-28028 April 2022 Annual Radioactive Environmental Operating Report for 2021 ML22118A5822022-04-28028 April 2022 Annual Radioactive Effluent Release Report for 2021 ML22091A1062022-04-0101 April 2022 Nuclear Onsite Property Damage Insurance (10 CFR 50.54(w)(3)) L-22-022, and Indian Point Nuclear Generating Stations 1, 2, & 3 - Report on Status of Decommissioning Funding for Reactors and Independent Spent Fuel Storage Installations - Holtec.2022-03-25025 March 2022 and Indian Point Nuclear Generating Stations 1, 2, & 3 - Report on Status of Decommissioning Funding for Reactors and Independent Spent Fuel Storage Installations - Holtec. ML22069A3762022-03-10010 March 2022 Late LLRW Shipment Investigation Report Pursuant to 10 CFR 20, Appendix G ML22032A0582022-03-0808 March 2022 EA-21-139; EA-150: Oyster Creek Nuclear Generating Station - NRC Investigation Report Nos.. 1-2021-002 & 1-2021-014 ML22060A2202022-03-0202 March 2022 NRC Office of Investigations Case No. 1-2021-009 ML22049B2452022-02-19019 February 2022 Late Low Level Radwaste Shipment Report Pursuant to 10 CFR 20 Appendix G IR 05000219/20214022022-01-26026 January 2022 EA-21-041: Confirmatory Order Related to Oyster Greek Nuclear Generating Station - NRC Investigation Report I-2020-007; NRC Inspection Report Nos. 05000219/2021402 & 07200015/2021401 ML22025A3422022-01-25025 January 2022 and Big Rock Point - Changes to Site Organization ML22025A2182022-01-25025 January 2022 Late LLRW Shipments Investigation Report Pursuant to 10 CFR 20, Appendix G ML22021B5512022-01-21021 January 2022 Compensatory Measures Not Implemented Per Site'S Physical Security Plan Due to Multiplexer (Mux) Power Supply Failure L-21-134, and Indian Point Nuclear Generating Stations 1, 2, & 3 - Report on Status of Decommissioning Funding for Independent Spent Fuel Storage Installations2021-12-17017 December 2021 and Indian Point Nuclear Generating Stations 1, 2, & 3 - Report on Status of Decommissioning Funding for Independent Spent Fuel Storage Installations ML21349A5192021-12-15015 December 2021 Commitment Change Summary Report ML21285A1912021-11-30030 November 2021 Nrc'S Analysis of Holtec Decommissioning International'S Decommissioning Funding Status Report for Oyster Creek Nuclear Generating Station and Pilgrim Nuclear Power Station, Docket Nos 50-219 and 50-293 IR 05000219/20210032021-11-16016 November 2021 NRC Inspection Report No. 05000219/2021003 L-21-118, Changes to Signature Authority & Addressee for Holtec Decommissioning International, LLC Correspondence Re to Oyster Creek Nuclear Generating Station, Pilgrim Nuclear Power Station, Indian Point Nuclear Generating Units 1, 2, 3, & Palisades2021-11-0909 November 2021 Changes to Signature Authority & Addressee for Holtec Decommissioning International, LLC Correspondence Re to Oyster Creek Nuclear Generating Station, Pilgrim Nuclear Power Station, Indian Point Nuclear Generating Units 1, 2, 3, & Palisades IR 05000219/20214042021-08-26026 August 2021 NRC Independent Spent Fuel Storage Security Inspection Report No. 07200015/2021402 and Security Decommissioning Inspection Report 05000219/2021404 - (Public) 2024-01-09
[Table view] Category:Licensee Event Report (LER)
MONTHYEARML22021B5512022-01-21021 January 2022 Compensatory Measures Not Implemented Per Site'S Physical Security Plan Due to Multiplexer (Mux) Power Supply Failure 05000219/LER-2017-0052018-01-0303 January 2018 1 OF 3, LER 17-005-00 for Oyster Creek Nuclear Generating Station Regarding Failure of the Emergency Diesel Generator #2 During Surveillance Testing Due to a Broken Electrical Connector 05000219/LER-2017-0032017-08-31031 August 2017 Automatic Scram while Suberitical due to Low Reactor Level, LER 17-003-00 for Oyster Creek Regarding Automatic Scram while Subcritical due to Low Reactor Level 05000219/LER-2017-0022017-08-31031 August 2017 Manual Reactor Scram due to Degrading Main Condenser Vacuum, LER 17-002-00 for Oyster Creek Regarding Manual Scram due to Degraded Main Condenser Vacuum 05000219/LER-2016-0022017-06-23023 June 2017 Control Rod Drive Cooling Water System Isolation Scram Time Testing Was Not Performed, LER 16-002-01 for Oyster Creek Regarding Control Rod Drive Cooling Water System Isolation Scram Time Testing Was Not Performed 05000219/LER-2017-0012017-05-0303 May 2017 Automatic SCRAM due to APRM High Flux during Turbine Valve Testing, LER 17-001-01 for Oyster Creek, Regarding Transfer of Automatic SCRAM due to APRM High Flux during Turbine Valve Testing ML17129A6032017-05-0303 May 2017 LER 16-S01-01 for Oyster Creek, Regarding Special Nuclear Material Discovered Outside of Material Access Area 05000219/LER-2016-0012017-01-24024 January 2017 1 OF 4, LER 16-001-01 for Oyster Creek Nuclear Generating Station Regarding Failure of the #1 Emergency Diesel Generator During Surveillance Testing due to a Cooling Water System Leak RA-16-107, LER 16-S01-00 for Oyster Creek Nuclear Generating Station Regarding Special Nuclear Material Discovered Outside of Material Access Area2016-12-0505 December 2016 LER 16-S01-00 for Oyster Creek Nuclear Generating Station Regarding Special Nuclear Material Discovered Outside of Material Access Area 05000219/LER-2016-0052016-11-17017 November 2016 Technical Specification Prohibited Condition Caused by One Electromatic Relief Valve Inoperable for Greater than Allowed Outage Time, LER 16-005-00 for Oyster Creek Nuclear Generating Station Regarding Technical Specification Prohibited Condition Caused by One Electromatic Relief Valve Inoperable for Greater than Allowed Outage Time 05000219/LER-2016-0032016-06-29029 June 2016 Manual SCRAM Inserted due to Leakage from the D' Reactor Recirculation Pump Seal, LER 16-003-00 for Oyster Creek, Unit 1, Regarding Manual SCRAM Inserted due to Leakage from the 'D' Reactor Recirculation Pump Seal RA-16-001, Special Report for Inoperability of the Turbine Building High Range Radioactive Noble Gas Monitor2016-01-15015 January 2016 Special Report for Inoperability of the Turbine Building High Range Radioactive Noble Gas Monitor ML1015505702009-08-26026 August 2009 Event Notification for Oyster Creek on Offsite Notification Due to a Water Leak Containing Tritium ML0932006252009-07-24024 July 2009 NRC Operations Center Event Report - Oyster Creek ML1015505672009-04-15015 April 2009 Event Notification for Oyster Creek on Offsite Notification Due to Potential Release of Tritium ML0506107132005-02-16016 February 2005 LER 04-03-001 Oyster Creek, Unit 1, Regarding Actuation of Reactor Protection System Due to Spurious Hi-Hi Trip Signals on Intermediate Range Monitors Caused by Electromagnetic Interference 2022-01-21
[Table view] |
comments regarding burden estimate to the Information Services Branch (T-2 F43), 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, used to impose an informahon collechdn 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
3. LER NUMBER
2017 - 01 001
Plant Conditions Prior To Event
Event Date: November 20, 2016 Event Time: 0342 EST Unit 1 Mode: Power Operation Power Level: 92%
Description of Event
On 11/20/2016, the Main Control Room (MCR) Operators were conducting quarterly Main Turbine surveillance testing. At 0326 EST, the MCR Operators commenced testing the Turbine Master Trip Solenoid Valve (MTS-3) at 95% reactor power in accordance with plant procedures. After actuating the Turbine Master Trip Solenoid Valve, the MCR Operators observed fluctuations in control valve and bypass valve position indication. The Control Room Operators also identified a transfer between the EPR and MPR and fluctuations in reactor pressure. Field Operators were dispatched to the turbine front standard to inspect for any abnormalities. The Field Operators reported vibration and high frequency oscillations of the control linkages contained in the front standard. In response to the field report, the MCR Operators commenced a controlled power reduction in an effort to arrest the oscillations.
At approximately 0342 EST, an automatic reactor SCRAM occurred at 92% power due to Average Power Range Monitor (APRM) high flux. The turbine control valves failed to properly control reactor pressure during the power reduction due to a malfunction of the Mechanical Hydraulic Control (MHC) System. After the plant scram, the_ vibration and oscillations at the front standard ceased, and the bypass valves responded to regulate reactor pressure. An inspection of the front standard and the turbine control valve hydraulic enclosure was performed following the plant shutdown. The inspection identified that the hydraulic feedback linkage for the number 2 turbine control valve had come disconnected and the fastener for the hydraulic feedback linkage on the number 4 control valve was loose due to the vibration that was experienced. The feedback linkage degradation resulted in the unexpected change in control valve position during the power reduction and the subsequent reactor scram.
Cause of Event
The root cause investigation determined that the performance of the Turbine Master Trip Solenoid Valve operability test with the plant at power challenged the stability of the MHC system due to unrecognized design vulnerability in the configuration of the hydraulic tubing. The hydraulic tubing for the Turbine Master Trip Solenoid Valve is routed to the bypass valve loading piston. The design function of the bypass valve loading piston is to dampen vibration on the control linkages contained in the front standard. During the Turbine Master Trip Solenoid Valve Operability Test, a pressure pulse is placed on the bypass pilot valve loading piston that can lead to an oscillation of the MHC system. The design vulnerability was unrecognized because the OEM drawings did not identify the function or location of the loading piston with respect to the location of the Master Trip Solenoid hydraulic supply.
The root cause investigation also determined that degradation of the bypass valve loading piston contributed to the oscillation of the MHC System.
Analysis of Event
Infocollects.Resource@nrc gov, and to the Desk Officer, Office of Information and Regulatory Affairs, 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.
3. LER NUMBER
2017 - 01 001 This issue resulted in an automatic reactor SCRAM. There were no equipment problems noted related to placing the reactor in a safe Cold Shutdown Condition.
There were no safety consequences impacting the plant or public safety as a result of this event. All control rods fully inserted and plant response was as expected. This event is being reported pursuant to 10CFR50.73(a)(2)(iv)(A) due to an actuation of the Reactor Protection System (RPS).
Corrective Actions
The following corrective actions were taken:
- The hydraulic linkage for the number 2 and number 4 control valves were repaired.
- The bypass valve loading piston was replaced.
- The turbine master trip solenoid valve test will no longer be performed online. The test will be performed during unit outage only.
Previous Occurrences
Oyster Creek Nuclear Generating Station experienced a similar event on December 14, 2013. During quarterly turbine valve testing with reactor power at 100% of rated thermal power, the plant experienced reactor pressure control abnormalities. The hydraulic feedback linkage for the number 2 and number 3 control valves failed, thereby requiring a scram. Operators initiated a manual reactor scram due to reactor pressure rising to 1042 psig which approached the automatic scram set point. That event was reported under LER 2013-004-00 in February 2014.
Component Data Component IEEE 805 System ID IEEE 803A Component Control Valve Hydraulic Enclosure TG XC