LER-2021-005, Condition Prohibited by Technical Specification Due to Setpoint Drift |
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10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
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| 3882021005R00 - NRC Website |
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Kevin Cimorelli Site Vice President Susquehanna Nuclear, LLC 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.3795 Fax 570.542.1504 Kevin.Cimorelii@TaJenEnergy.com Februaiy 11, 2022 Attn: Document Control Desk U.S. Nuclear Regulat01y Commission Washington, DC 20555-0001 SUSQUEHANNA STEAM ELECTRIC STATION LICENSEE EVENT REPORT 50-388/2021-005-00 UNIT 2 LICENSE NO. NPF-22 PLA-7982 TALEN4 ENERGY 10 CFR 50.73 Docket No. 50-388 Attached is Licensee Event Report (LER) 50-388/2021-005-00. The LER reports an event in which the Unit 2 'B' Reactor Protection System and Primary Contaimnent Isolation System were inoperable for longer than allowed by Technical Specifications (TS). The condition is being repmted in accordance with 10 CFR 50.73(a)(2)(i)(B) as condition prohibited by TS.
There were no actual consequences to the health and safety of the public as a result of this event.
This letter contains no new or revised regulatmy commitments.
K. Cimorelli Attachment: LER 50-388/2021-005-00 Copy: NRC Region I Mr. C. Highley, NRC Senior Resident Inspector Ms. A. Klett, NRC Project Manager Mr. M. Shields, PA DEP/BRP
Abstract
At approximately 13:50 on December 15, 2021, during surveillance testing, personnel at the Susquehanna Steam Electric Station, Unit 2, found the setpoint for the Unit 2 B Reactor Vessel Water Level Narrow Range Indicator had drifted outside of its Technical Specification (TS) Allowable Value (AV). Operators declared the Reactor Protection System and the Primary Containment Isolation System inoperable, and entered TS 3.3.1.1, Condition A, and TS 3.3.6.1, Condition A. The level indicators setpoint was adjusted to within the TS AV, and TS 3.3.1.1, Condition A, and TS 3.3.6.1, Condition A, were exited at 15:42 on December 15.
Based on the information available, the condition is considered to have existed for longer than allowed by TS 3.3.1.1 and TS 3.3.6.1. Therefore, the condition is being reported in accordance with 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by the plants TS.
The cause of the event is under investigation and will be provided in a supplement to this report with associated corrective actions. There were no actual safety consequences associated with the described condition.
CONDITIONS PRIOR TO EVENT
Unit 1 - Mode 1, approximately 98 percent Rated Thermal Power (RTP)
Unit 2 - Mode 1, approximately 100 percent RTP
EVENT DESCRIPTION
At approximately 13:50 on December 15, 2021, during surveillance testing, personnel at the Susquehanna Steam Electric Station, Unit 2, found the setpoint for the Unit 2 B Reactor Vessel Water Level Narrow Range Indicator LISB212N024B [EIIS System/Component Code: JC/LIS] had drifted outside of its Technical Specification (TS) Allowable Value (AV). Operators declared the Reactor Protection System and the Primary Containment Isolation System [JM] inoperable, and entered TS 3.3.1.1, Reactor Protection System (RPS)
Instrumentation, Condition A, and TS 3.3.6.1, Primary Containment Isolation Instrumentation, Condition A.
LISB212N024B was adjusted to within the TS AV, and TS 3.3.1.1, Condition A, and TS 3.3.6.1, Condition A, were exited at 15:42 on December 15.
Based on the information available, the condition is considered to have existed for longer than allowed by TS 3.3.1.1 and TS 3.3.6.1. Therefore, the condition is being reported in accordance with 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by the plants TS.
CAUSE OF EVENT
The cause of the event is under investigation and will be provided in a supplement to this Licensee Event Report (LER).
ANALYSIS/SAFETY SIGNIFICANCE
The safety significance of this event is under review and will be provided in a supplement to this LER.
CORRECTIVE ACTIONS
Corrective actions will be provided in a supplement to this LER.
COMPONENT FAILURE INFORMATION
Component failure information will be provided in a supplement to this LER.
PREVIOUS OCCURRENCES
Previous similar occurrences, if any, will be provided in a supplement to this LER.
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| 05000388/LER-2021-001-01, Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switch | Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switch | 10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000388/LER-2021-001, Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switch | Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switch | 10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000387/LER-2021-001, Electri Station, Unplanned Lnoperability of the High Pressure Coolant Injection (HPCI) System Due to a Primary Containment Isolation (PCIV) Valve Failure to Stroke Full Closed On-demand Due to an Intermittent Break | Electri Station, Unplanned Lnoperability of the High Pressure Coolant Injection (HPCI) System Due to a Primary Containment Isolation (PCIV) Valve Failure to Stroke Full Closed On-demand Due to an Intermittent Break | 10 CFR 50.73(a)(2)(v), Loss of Safety Function | | 05000388/LER-2021-002-01, Loss of Secondary Containment Due to Failed Differential Pressure Transmitter | Loss of Secondary Containment Due to Failed Differential Pressure Transmitter | 10 CFR 50.73(a)(2)(v), Loss of Safety Function | | 05000388/LER-2021-002, Re Loss of Secondary Containment | Re Loss of Secondary Containment | 10 CFR 50.73(a)(2)(v), Loss of Safety Function | | 05000387/LER-2021-002, Inoperability of Computer Room Floor Cooling Fan Caused by Extended Operation with Worn Belts Due to Less than Adequate Preventive Maintenance Replacement Interval | Inoperability of Computer Room Floor Cooling Fan Caused by Extended Operation with Worn Belts Due to Less than Adequate Preventive Maintenance Replacement Interval | 10 CFR 50.73(a)(2)(v), Loss of Safety Function
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000388/LER-2021-003-01, Automatic Reactor Scram Due to Main Turbine Trip Caused by Inadvertent Trip of the Main Generator Output Breakers | Automatic Reactor Scram Due to Main Turbine Trip Caused by Inadvertent Trip of the Main Generator Output Breakers | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000387/LER-2021-003-01, Automatic Reactor Scram Due to Main Turbine Trip Caused by a C Isophase Bus Ground Fault | Automatic Reactor Scram Due to Main Turbine Trip Caused by a C Isophase Bus Ground Fault | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000387/LER-2021-003, Automatic Reactor Scram Due to Main Turbine Trip | Automatic Reactor Scram Due to Main Turbine Trip | 10 CFR 50.73(a)(2)(iv)(A), System Actuation | | 05000388/LER-2021-004-01, From Susquehanna Steam Electric Station, Unit 2 Main Turbine Pressure Regulator Inoperable for Longer than Allowed by Technical Specifications Due to Inadequate Valve Modification | From Susquehanna Steam Electric Station, Unit 2 Main Turbine Pressure Regulator Inoperable for Longer than Allowed by Technical Specifications Due to Inadequate Valve Modification | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000387/LER-2021-004-01, Loss of 1B RHRSW Pump Due to Cable Damage During Excavation Activities | Loss of 1B RHRSW Pump Due to Cable Damage During Excavation Activities | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000387/LER-2021-004, Loss of 1B RHRSW Pump Due to Cable Damage During Excavation Activities | Loss of 1B RHRSW Pump Due to Cable Damage During Excavation Activities | 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat
10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000388/LER-2021-005-01, Condition Prohibited by Technical Specification Due to Setpoint Drift Attributed to Age Related Degradation | Condition Prohibited by Technical Specification Due to Setpoint Drift Attributed to Age Related Degradation | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000387/LER-2021-005-01, Automatic Reactor Scram Due to Turbine Control Valve Fast Closure | Automatic Reactor Scram Due to Turbine Control Valve Fast Closure | 10 CFR 50.73(a)(2)(iv)(A), System Actuation
10 CFR 50.73(a)(2) | | 05000388/LER-2021-005, Condition Prohibited by Technical Specification Due to Setpoint Drift | Condition Prohibited by Technical Specification Due to Setpoint Drift | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications | | 05000387/LER-2021-005, Automatic Reactor Scram Due to Turbine Control Valve Fast Closure | Automatic Reactor Scram Due to Turbine Control Valve Fast Closure | 10 CFR 50.73(a)(2)(iv)(A), System Actuation |
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