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| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 53828 | 16 January 2019 05:00:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Secondary Containment Differential Pressure Exceeded Technical Specification Allowed Value | On January 16, 2019, with James A. Fitzpatrick Nuclear Power Plant operating at 100 percent power, the Emergency and Plant Information Computer (EPIC) indicated that Secondary Containment differential pressure exceeded the Technical Specification Surveillance Requirement of greater than or equal to 0.25 inches of vacuum water gauge while isolating Reactor Building Ventilation. The Secondary Containment differential pressure was less than 0.25 inches of vacuum water gauge for approximately ten (10) seconds, and then immediately returned to greater than or equal to 0.25 inches of vacuum water gauge. This condition did not impact the leak tightness of Secondary Containment or the ability of the Standby Gas Treatment system to establish and maintain the required differential pressure. When Secondary Containment did not meet the Technical Specification Surveillance Requirement 3.6.4.1.1 for differential pressure, the Limiting Condition of Operation (LCO) was not met. Therefore, Secondary Containment was inoperable. This event is being reported under 10 CFR 50.72(b)(3)(v)(C). The licensee has notified the NRC Resident Inspector. | Secondary containment Reactor Building Ventilation Standby Gas Treatment System | |
| ENS 53778 | 5 December 2018 05:00:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Three Minute Loss of Secondary Containment Vacuum | At 1010 (EST) on December 5, 2018, Secondary Containment differential pressure exceeded the Technical Specification Surveillance Requirement of greater than or equal to 0.25 inches of vacuum water gauge. This condition existed for approximately 3 minutes before the differential pressure was restored to normal when the Standby Gas Treatment system was manually initiated. This event was caused by a trip of the service air compressor 39AC-2A. The loss of instrument air pressure caused Reactor Building ventilation to isolate and raise Secondary Containment differential pressure. The instrument air pressure was restored when 39AC-2A was isolated and the two backup air compressors started. This condition did not impact the leak tightness of Secondary Containment or the ability of the Standby Gas Treatment system to establish and maintain the required differential pressure. When Secondary Containment did not meet the Technical Specification Surveillance Requirement 3.6.4.1.1 for differential pressure, the Limiting Condition of Operation (LCO) was not met. Therefore, Secondary Containment was inoperable. This event is being reported under 10 CFR 50.72(b)(3)(v)(C). The licensee notified the NRC Resident Inspector. | Secondary containment Reactor Building Ventilation Standby Gas Treatment System | |
| ENS 52343 | 2 November 2016 12:45:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Residual Heat Removal Valve Inoperable for Containment Isolation | During panel walkdown, it was discovered that a tag out for the 'C' Residual Heat Removal pump suction valve was active and the valve was open with its breaker open. This rendered the valve inoperable and Technical Specification 3.6.1.3 Action C for penetration with one inoperable PCIVs was entered. The action was to isolate the penetration by closing the valve within (4) hours or restore power. The event was discovered at 0845 (EDT) and the breaker was closed at 0925 (EDT). Technical Specification 3.6.1.3 Action C (Isolate penetration within 4 hrs.) was entered at 0130 (EDT) (time breaker was opened per tagout) and exited at 0925 (EDT). This condition of non-compliance existed from 0530 (EDT) on 11/02/16 until 0925 (EDT) on 11/02/16. This event is being reported under 10CFR50.72 (b)(3)(v)(C). NRC Resident has been notified.
In accordance with Technical Specification (TS) 3.6.1.3, Primary Containment Isolation Valves, the TS Basis states that one or more barriers are provided for each penetration so that no single credible failure or malfunction of an active component can result in a loss of isolation or leakage that exceeds limits assumed in the safety analyses. When two or more barriers are provided, one of these barriers may be a closed system. During this event, one of the barriers in the penetration became inoperable: 'C' Residual Heat Removal (RHR) pump suction valve 10MOV-13C. After the initial NRC notification, it was confirmed that the RHR system piping is classified as a closed system outside containment. The integrity of the closed-loop RHR system is verified by monitoring the keep-full system. Since the piping is maintained full of water during normal and post-accident modes of operation, a barrier against post-accident, gaseous, containment leakage is provided. Therefore, the affected penetration could have performed its intended safety function since there was redundant equipment in the same system which was operable. This event is not reportable under 10 CFR 50.72(b)(3)(v)(C) and the original notification may be retracted. Finally, the primary containment penetration with 10MOV-13C is with a closed system and the completion time per TS 3.6.1.3 Required Action C is 72 hours. The valve was restored to operable prior to exceeding this time. The licensee notified the NRC Resident Inspector. Notified the R1DO (Dentel). | Primary containment Residual Heat Removal | |
| ENS 51985 | 7 June 2016 14:30:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Both Secondary Containment Doors Open Simultaneously | At 1030 EDT on 6/7/2016, both doors of a secondary containment airlock were reported to be simultaneously open for approximately 2 seconds during the normal passage of personnel. The brief time that the doors were simultaneously open constitutes an inoperable condition of secondary containment. Secondary containment differential pressure was maintained throughout the time period that the doors were open. This event is being reported under 10 CFR 50.72(b)(3)(v)(C) and per the guidance of NUREG-1022, Rev. 3, 'any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to control the release of radioactive material.' The licensee notified the NRC Resident Inspector. | Secondary containment | 05000333/LER-2016-003 |
| ENS 51579 | 2 December 2015 01:36:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Secondary Containment Inoperable Due to Secondary Containment Vacuum Being Less than Required Ts Value | On December 1, 2015 at 2036 EST, with James A. FitzPatrick Nuclear Power Plant (JAF) operating at 100 percent power, Secondary Containment differential pressure exceeded the Technical Specification (TS) Surveillance Requirement (SR) of greater than or equal to 0.25 inches of vacuum water gauge for approximately one (1) minute and twenty (20) seconds. Secondary Containment (SC) had been declared inoperable prior to this event, to facilitate a planned evolution related to a previous failure that occurred on September 18, 2015 (reference EN #51409). Operators attempted to restore the Reactor Building Ventilation System (RBVS) to the normal system lineup upon completion of the planned evolution. The Secondary Containment differential pressure trended positive, and exceeded the TS SR differential pressure requirement during this transition. Preliminary investigations indicate that the cause of this event is associated with the Above Refuel Floor Exhaust Fan (66FN-13B). The design of the Above Refuel Floor Exhaust portion of the RBVS includes an interlock between the exhaust fan and a downstream damper position switch, which starts the fan when the damper is in the full open position. During the approximate one (1) minute and twenty (20) second duration that the TS SR was not met, 66FN-13B was not running with the associated discharge damper in the open position. Secondary Containment was operable after the SC differential pressure was restored upon start of 66FN-13B, and remains operable. This event is reportable pursuant to 10 CFR 50.72(b)(3)(v)(c), as an event or condition that could have prevented fulfillment of a safety function. The licensee notified the NRC Resident Inspector. | Secondary containment Reactor Building Ventilation | 05000333/LER-2015-007 |
| ENS 51512 | 22 September 2015 20:09:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Secondary Containment Differential Pressure Exceeded Technical Specification Allowed Value | On September 22, 2015, with James A. Fitzpatrick Nuclear Power Plant operating at 100 percent power, the Emergency and Plant Information Computer (EPIC) indicated a spike in Secondary Containment differential pressure during performance of a surveillance test associated with automatic initiation of the Standby Gas Treatment System. Plant data systems recorded Secondary Containment differential pressure exceeding the Technical Specification allowed value. The Secondary Containment differential pressure was at or above zero inches of water for approximately ten (10) seconds, and then immediately trended negative following auto-start of one of the trains of Standby Gas Treatment. An operator was subsequently dispatched to the ventilation control panel, and verified that Secondary Containment differential pressure was more negative than the Technical Specification allowed value. This condition was entered into the Corrective Action Program, and subsequently, it was determined that the approximate ten second duration that Secondary Containment differential pressure was greater than the Technical Specification allowed value was reportable pursuant to 10 CFR 50.72(b)(3)(v)(C), as an event or condition that could have prevented fulfillment of a safety function. Secondary Containment was Operable following reestablishment of greater than or equal to 0.25 inches of water vacuum, and remains Operable. The licensee has notified the NRC Resident Inspector. | Secondary containment Standby Gas Treatment System | 05000333/LER-2015-006 |
| ENS 51409 | 18 September 2015 18:08:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Equipment Failure Results in Inoperable Secondary Containment | At 1408 EDT on 9/18/2015, Secondary Containment Refuel Floor exhaust flow degraded due to an equipment malfunction in the running Refuel Floor exhaust train. The degraded exhaust flow caused Secondary Containment differential pressure to go positive for approximately three minutes, resulting in Secondary Containment being declared inoperable. Corrective action to start the Stand-by Gas Treatment System and the alternate Refuel Floor exhaust train restored Secondary Containment operable by re-establishing its required negative differential pressure. This event is being reported under 10 CFR 50.72(b)(3)(v)(C) and per the guidance of NUREG-1022, Rev. 3, 'Any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to control the release of radioactive material.' The Duty Team has been activated to develop a repair plan. The NRC Resident Inspector has been notified. | Secondary containment | 05000333/LER-2015-005 |
| ENS 51405 | 17 September 2015 16:20:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Brief Loss of Secondary Containment Due to Both Airlock Doors Open Simultaneously | At 1220 (EDT) on 9/17/2015, both doors of a Secondary Containment airlock were reported to be simultaneously open for approximately five seconds during the normal passage of personnel. The brief time that the doors were simultaneously open constitutes an inoperable condition of Secondary Containment. Secondary Containment differential pressure was maintained throughout the time period that the doors were open. This event is being reported under 10 CFR 50.72(b)(3)(v)(C) and per the guidance of NUREG-1022, Rev. 3, 'Any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to control the release of radioactive material.' The NRC Resident Inspector has been notified. | Secondary containment | 05000333/LER-2015-004 |
| ENS 51242 | 20 July 2015 11:40:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Temporary Loss of Differential Pressure in Secondary Containment | On the morning of July 20, 2015 at 0740 EDT, with James A. FitzPatrick Nuclear Power Plant (JAF) operating at 100 percent power, the Secondary Containment differential pressure decreased below the JAF Technical Specification (TS) Surveillance Requirement (SR-3.6.4.1.1) value of greater than or equal to 0.25 inch of vacuum water gauge. Both trains of the Standby Gas Treatment System were placed in service and the Reactor Building was isolated. The decrease in Secondary Containment differential pressure was caused by Reactor Building roof maintenance creating multiple openings. Maintenance workers were immediately ordered to stop work and address the condition. Secondary Containment differential pressure was restored to within the TS SR value at 0915 EDT, and remains greater than 0.25 inch of vacuum water gauge. The secondary containment is a structure that surrounds the primary containment and is designed to provide secondary containment for postulated loss-of-coolant accidents inside the primary containment. To prevent exfiltration the secondary containment requires the control volume pressure at less than the external pressure. The differential pressure requirement of TS SR-3.6.4.1.1 ensures that the secondary containment boundary is sufficiently leak tight to preclude exfiltration. During this period there were no unmonitored radioactive releases; however, this event could have prevented the fulfillment of a safety function to control the release of radioactive material and it is reported pursuant to 10 CFR 50.72(b)(3)(v)(C). The NRC Resident Inspector has been informed. | Secondary containment Primary containment Standby Gas Treatment System | 05000333/LER-2015-003 |
| ENS 50579 | 28 October 2014 21:08:00 | 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | Reactor Building Vacuum Below Technical Specification Limit | On the evening of October 28, 2014 at 1708 EDT, with James A. FitzPatrick (JAF) Nuclear Power Plant operating at 100 percent power, the Reactor Building differential pressure decreased below the JAF Technical Specification (TS) Surveillance Requirement (SR) value of at least 0.25 inches water vacuum for a period of thirty-four (34) seconds. This occurred during restoration of the Reactor Building Ventilation System (RBVS) following planned maintenance. The Reactor Building differential pressure was 0.50 inches water vacuum with the 'A' RBVS fans in-service in conjunction with the Standby Gas Treatment System (SGTS). The Reactor Building differential pressure decreased to 0.19 inches water vacuum when the SGTS was secured. The Reactor Building Vent was subsequently isolated, and the alternate 'B' RBVS fans were placed in-service; the differential pressure increased to within the required 0.25 inches water vacuum value. The JAF TS bases associated with Secondary Containment state that, 'for Secondary Containment to be considered OPERABLE, it must have adequate leak tightness to ensure that the required vacuum can be established and maintained.' Troubleshooting activities indicated that the transient was due to a non-safety related, non-TS damper downstream of one of the 'A' RBVS fans that did not fully stroke open. The subject damper is not part of Secondary Containment, and has no safety related function. This condition did not impact the leak tightness of Secondary Containment or the ability of the associated equipment to establish and maintain the required differential pressure. Secondary Containment would have fulfilled its safety function. However, because the JAF TS SR value of 0.25 inches water vacuum was not met, Secondary Containment was considered Technical Specification INOPERABLE for a period of thirty-four (34) seconds. The Secondary Containment is considered a single-train system; therefore, this condition is reportable pursuant to 10 CFR 50.72(b)(3)(v)(C) as an event or condition that could have prevented fulfillment of a safety function. The licensee notified the NRC Resident Inspector. | Secondary containment Reactor Building Ventilation Standby Gas Treatment System | 05000333/LER-2014-002 |