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| Entered date | Event description | |
|---|---|---|
| ENS 54607 | 25 March 2020 03:30:00 | At 0056 EDTon March 25, 2020, with Unit 1 at 17 percent power during a unit power ascension, the reactor was manually tripped due to the failure of the 11 Rod Control Motor Generator caused by a malfunction of its associated Voltage Regulator. The trip was not complex, with all systems responding normally post-trip. An actuation of the Auxiliary Feedwater system occurred following the manual reactor trip as expected due to low level in the steam generators. The unit is stable in Mode 3. Decay heat is being removed by the Atmospheric Steam Dumps and Auxiliary Feedwater System. Salem Unit 2 was not affected. Due to the actuation of the Reactor Protection System actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B), This event is also being reported as an eight hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the Auxiliary Feedwater System. There was no impact to the health and safety of the public or plant personnel. The NRC Resident lnspector has been notified. |
| ENS 53852 | 31 January 2019 04:23:00 | At 0301 (EST) on 1/31/19, with Unit 2 in Mode 1 at 100% power, the reactor was manually tripped due to icing conditions requiring the removal of 4 Circulating Water Pumps from service. The trip was not complex, with all systems responding normally post-trip. 21 CFCU (Containment Fan Cooler Unit) was inoperable prior to the event for a planned maintenance window and did not contribute to the cause of the event and did not adversely impact the plant response to the trip. An actuation of the Auxiliary Feedwater System occurred following the manual reactor trip. The reason for the Auxiliary Feed Water System auto-start was due to low level in a steam generator. Operations responded and stabilized the plant. Decay heat is being removed by the Main Steam Dumps and Auxiliary Feedwater System. Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). This event is also being reported as an eight hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the Auxiliary Feed Water System. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. The icing condition was described as frazil ice. Unit-1 reduced power to 88% because one circulating water pump was shutdown. |
| ENS 51734 | 14 February 2016 23:13:00 | This 4-hour and 8-hour notification is being made to report that Salem Unit 2 had an unplanned automatic reactor trip. The trip occurred because the Unit 2 main generator tripped on generator protection with reactor power greater than P-9 (49%). The cause of the generator protection trip that resulted in the reactor trip is unknown at this time. A troubleshooting team is being assembled to determine the exact cause for the generator protection actuation. All control rods inserted on the reactor trip. All ECCS and ESF systems functioned as expected. The motor driven and steam driven auxiliary feed pumps started as expected on steam generator low level. Salem Unit 2 is currently in mode 3. Reactor Coolant System pressure is at 2235 psig and temperature is 547 degrees Fahrenheit with decay heat removal via the main steam dumps and auxiliary feedwater systems. Unit 2 has no active technical specification action statement in effect requiring a lower mode of operation. No safety related equipment or major secondary plant equipment was tagged for maintenance prior to the event. There were no personnel injuries as a result of this event. There was no impact on Salem Unit 1. The licensee informed the NRC Resident Inspector and will inform the Lower Alloways Creek Township (LAC). |
| ENS 48071 | 5 July 2012 17:45:00 | On 7/5/12 at 0307 hrs (EDT), Salem Unit 2 declared 21 Auxiliary Feedwater Pump out of service due to the failure of the 23AF21, Auxiliary Feedwater Flow Control valve to the 23 Steam Generator. 23AF21 had failed to a full open position during performance of the in-service test. Salem Unit 2 entered Technical Specification 3.7.1.2 a, Action Statement a, which requires restoring the pump to operable status within 72 hours, otherwise be in at least Hot Standby within the next 6 hrs and in Hot Shutdown within the following 6 hours. At 1000 hrs on 7/5/12, the air supply to the 23AF21 was found isolated. Troubleshooting and repair of the 23AF21 was completed and, following in service testing, the valve was declared operable at 1349 hrs. Review of the valve's operability concluded that the failure of the 23AF21 valve to close represented a condition that could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident. The Salem UFSAR assumes that during a Category IV Main Steam break accident, a faulted Steam Generator would be identified and Auxiliary Feedwater would be isolated to the affected Steam Generator within 10 minutes. Since the valve was failed open and could not be operated from the control room, the plant would have to manually isolate 23AF21 or trip the 21 Auxiliary Feedwater Pump to ensure feedwater isolation to the affected, faulted Steam Generator. The time to perform manual isolation or tripping of the Auxiliary Feedwater Pump may have required more time than that analyzed by the plant UFSAR. This is being reported under 10CFR50.72(b)(3)(v), the nuclear plant being in a condition that could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident. There were no other safety related systems affected by this event and there were no injuries associated with this event. Maintenance was last performed on this system on May 17, 2012. The licensee will notify the NRC Resident Inspector and Lower Alloways Creek Township. |