Reactor Core Isolation Cooling (RCIC) is a system which injects cooling water at high pressure. Not as much water as HPCI
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| | Site | Start date | Title | Description |
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| ENS 57021 | Hatch | 11 March 2024 17:37:00 | Manual Reactor Trip | The following information was provided by the licensee via phone and email:
On March 11, 2024, at 1337 EDT, with Unit 1 in Mode 1 at 35 percent power performing power ascension activities, the reactor was manually tripped due to the 'A' reactor feed pump (RFP) tripping on low suction pressure. Due to the power level at the time, the 'B' RFP had not been placed in service. Closure of containment isolation valves (CIVs) in multiple systems and actuation of high-pressure coolant injection (HPCI) and reactor core isolation cooling (RCIC) occurred as a result of reaching the actuation setpoint on reactor water level as designed. The trip was not complex, with all safety systems responding normally post-trip. Operations responded and stabilized the plant. The 'B' RFP was placed in service and is controlling reactor water level. Decay heat is being removed by discharging steam to the main condenser using turbine bypass valves. Unit 2 is not affected.
Due to the emergency core cooling system (ECCS) discharging into the reactor, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(A). Also, the Reactor Protection System actuation while critical is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). Additionally, it is reportable under 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of CIVs, RCIC and HPCI.
There was no impact on the health and safety of the public or plant personnel. The NRC resident inspector has been notified.
The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
The cause of the 'A' RFP is under investigation. The reactor electric plant remains in a normal lineup with both emergency diesel generators available. There were no temperature or pressure technical specification limits approached. | | ENS 56989 | Cooper | 22 February 2024 17:03:00 | Accident Mitigation - High Pressure Coolant Iinjection Declared Inoperable | The following information was provided by the licensee via email:
At 1103 CST on February 22, 2024, a potential through-wall steam leak was identified on the high pressure coolant injection (HPCI) steam supply 1-inch drain line. As a result, HPCI was declared inoperable. Since HPCI is a single-train system, this is a condition that could have prevented the fulfillment of a safety function; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(D). Reactor core isolation cooling (RCIC) and low pressure emergency core cooling systems (ECCS) remain operable.
Additional investigation is in progress.
There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. | | ENS 56974 | Brunswick | 17 February 2024 13:37:00 | Primary Containment Degraded | The following information was provided by the licensee via email and phone call:
At 0837 EST, on 02/17/2024, during a refueling outage at 0 percent power while performing local leak rate testing (LLRT) on the reactor core isolation cooling (RCIC) isolation valves, which is part of the containment boundary, it was determined that the Unit 1 primary containment leakage rate did not meet 10 CFR 50 Appendix J requirements specified in Technical Specification 5.5.12. This event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A).
There was no impact on the health and safety of the public or plant personnel.
The NRC Resident Inspector has been notified. | | IR 05000333/2023004 | FitzPatrick | 7 February 2024 | Integrated Inspection Report 05000333/2023004 and Independent Spent Fuel Storage Installation Inspection Report 07200012/2023001 | | | IR 05000354/2023004 | Hope Creek | 1 February 2024 | Integrated Inspection Report 05000354/2023004 | | | IR 05000220/2023004 | Nine Mile Point | 1 February 2024 | Integrated Inspection Report 05000220/2023004 and 05000410/2023004 | | | IR 05000352/2023004 | Limerick | 31 January 2024 | Integrated Inspection Report 05000352/2023004 and 05000353/2023004 | | | IR 05000321/2023004 | Hatch | 31 January 2024 | Integrated Inspection Report 05000321/2023004 and 05000366/2023004 | | | ENS 56936 | Peach Bottom | 29 January 2024 17:02:00 | Automatic Reactor Scram | The following information was provided by the licensee via email:
At approximately 1202 EST on 01/29/24, unit 2 experienced a reactor scram caused by a main turbine trip. Investigation is still ongoing.
The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
All control rods were fully inserted. The licensee indicated that the turbine trip may have been caused by a power load imbalance, however the cause of the incident is under investigation. The scram was not complex.
Decay heat is currently being removed thru bypass valves dumping to the main condenser. Initially unit 2 lost the use of the bypass valves due to lack of condenser vacuum. Unit 2 used the high pressure coolant injection (HPCI) system in the condenser storage tank (CST) to CST mode to remove decay heat. Residual heat removal was used to keep the torus cool. Condenser vacuum was regained and unit 2 is back to removing decay heat with the turbine bypass valves.
There was no impact to unit 3.
The licensee confirmed there was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
- * *UPDATE ON 01/29/24 AT 1935 EST FROM PAUL BOKUS TO NATALIE STARFISH* * *
The following information was provided by the licensee via email:
Licensee adds 8-hour non-emergency 10 CFR 50.72(b)(3)(iv)(A) specified system actuation report to original 4-hour non-emergency 10 CFR 50.72(b)(2)(iv)(B) RPS Actuation report.
At approximately 1202 EST on 01/29/24, unit 2 experienced a reactor scram by a main turbine trip. All control rods inserted. Reactor core isolation cooling system (RCIC) was manually initiated for level control. HPCI was manually initiated for pressure control. Primary containment isolation system (PCIS) Group II and III isolations occurred (specified system actuation). Investigation is ongoing.
The NRC Resident Inspector has been notified. | | IR 05000397/2023004 | Columbia | 29 January 2024 | Integrated Inspection and Independent Spent Fuel Storage Installation Report 05000397/2023004 and 07200035/2023001 | |
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