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| Entered date | Event description | |
|---|---|---|
| ENS 52805 | 15 June 2017 11:32:00 | This is to report the Salem Unit 2, 2C Emergency Diesel Generator (EDG) actuation due to an invalid signal. This report is being made per paragraphs 10CFR50.73(a)(1) and 10CFR50.73(a)(2)(iv)(A) to address the invalid actuation of the 2C EDG on April 16, 2017, while performing the 2C Safeguards Equipment Controller (SEC) Mode OPS Surveillance test. Plant conditions: Salem Unit 2 was in mode 5 at the time of the invalid actuation. On April 16, 2017, at approximately 1053 (EDT) while performing Solid State Protection System (SSPS) testing of the 2C SEC, the 2C Emergency Diesel Generator (EDG) output breaker was manually opened per the associated procedure step. The EDG output breaker unexpectedly reclosed and the 2C 4kV vital bus loaded onto the EDG in SEC Mode 2. The cause of the 2C EDG output breaker reclosure and 2C 4kV Vital bus loading during testing was determined to be two faulty input block switches in the 2C SEC. When Step 5.2.27 of the test procedure was performed, the 2C SEC 'input block' switches failed to block a 'blackout' actuation signal. This resulted in the breaker reclosure and loading of the 2C Vital Bus onto the EDG. Trouble shooting identified that the two failed switches exhibited high resistance across the switch contacts which is indicative of being in a 'fail to block' (the input signal) condition. The licensee has notified the NRC Resident Inspector. The licensee will also notify the States of New Jersey and Delaware. |
| ENS 52681 | 14 April 2017 16:45:00 | At 1357 (EDT) on April 14, 2017, an unplanned automatic start signal was generated for the 2C Emergency Diesel Generator (EDG). The station was in the process of transferring the 2C 4160 volt vital bus from the 24 Station Power Transformer (SPT) to the 23 SPT, which are the offsite power in-feeds for the 2C 4160 volt vital bus. The 24 SPT infeed breaker opened as expected; however, the 23 SPT infeed breaker failed to close. The failure to swap from the 24 SPT to 23 SPT resulted in a momentary loss of power to the 2C 4160 volt vital bus generating the automatic start signal for the 2C EDG. The 2C 4160 volt vital bus was automatically re-energized by the 2C EDG as expected. Abnormal operating procedures were entered for loss of the 2C 4160 volt vital bus. Salem Unit 2 was in Mode 1 operating at 100% power. All equipment operated as expected. At 1555 (EDT), 2C 4160 volt vital bus was reenergized from 24 SPT, and the 2C EDG was secured in accordance with station implementing procedures. There was no impact to the health and safety of the public. The Resident Inspector has been notified. The Lower Alloways Creek Township, State of New Jersey, and State of Delaware will be notified. |
| ENS 46774 | 21 April 2011 19:16:00 | A manual trip of Salem Unit 1 was initiated due to a loss of circulating water pumps from heavy grassing at the circulating water intake. All rods fully inserted on the trip and all systems responded as designed with decay heat being removed via the steam dump system. All Auxiliary Feed Water (AFW) pumps auto started as expected on low steam generator levels from the trip. During a period of heavy grassing with one circulating water pump out of service for maintenance and another out of service for water box cleaning, a third circulating water pump's screen stopped and this circulating water pump was emergency tripped. When this circulating water pump was emergency tripped, the adjacent circulating water pump received a large intake of grass and automatically tripped. The abnormal operating procedure provides guidance to trip the plant if less than three circulating water pumps are in service and power is above P-10. At this point the manual reactor trip was initiated. The crew entered EOP-TRIP-1, appropriately transitioned to EOP-TRlP-2 and stabilized the plant at no load conditions. Salem Unit 1 is currently in mode 3. Reactor Coolant System temperature is 547F with pressure at 2235 psig. All ECCS and ESF Systems are available. Salem Unit 2 is currently defueled in a planned refueling outage and there is no impact to Salem Unit 2. No personnel injuries have occurred as a result of the trip. This event is reportable per 10CFR50.72(b)(3)(iv)(A) due to the auto start of the AFW pumps. This event is reportable per 10CFR50.72(b)(2)(iv)(B) due to the manual reactor trip. The plant is aligned with a normal electrical line-up from offsite power sources. The Licensee has notified the NRC Resident Inspector. The Licensee will notify Lower Alloways Creek Township and the States of New Jersey and Delaware.
During the post-trip data review for the manual reactor trip that occurred on April 21, 2011 at 1601 (EDT), 2 additional automatic Auxiliary Feedwater (AFW) pump start signals were identified. Operators were controlling AFW level to maintain steam generator levels within the band required by the emergency operating procedures. At approximately 1615 (EDT) the 13 steam generator level had cleared the low level setpoint but subsequently dipped below the low level setpoint at 1623 (EDT). At approximately 1640 (EDT), the 14 steam generator had recovered above the low level setpoint and subsequently dipped below the low level setpoint. The Unit 1 reactor had been previously tripped at 1601 (EDT) and all AFW pumps had automatically started. The 13 turbine driven AFW pump was stopped at approximately 1625 (EDT). The two motor driven AFW pumps continued to run throughout this event. Low level in one steam generator generates an automatic start of the motor driven AFW pumps and is reportable per 10CFR50.72(b)(3)(iv)(A). The licensee notified the NRC Resident Inspector and will notify Lower Alloways Creek Township and the States of New Jersey and Delaware. Notified the R1DO (Cook). |
| ENS 45821 | 7 April 2010 21:11:00 | On 4/06/10, Salem management was notified that samples taken from the Salem Unit 2 north storm drain system were positive for tritium. Two storm drain catch basin sample results were confirmed above 1 million pico Curies per liter. The affected area of the north storm drain system has been isolated. Samples upstream of the river outfall were less than the minimum detectable level for tritium. NRC reporting criteria were reviewed and, although no direct reportable criteria were met, based on the public sensitivity to tritium issues, it was determined that a voluntary notification to the NRC was prudent. Salem is taking action to mitigate, locate, and remediate the source of the tritium. In addition to isolating the affected portion of the system, the station has increased the sample frequency for the storm drain system and ground water wells in the affected area. A voluntary notification has been made to the appropriate State agency and the NRC Resident Inspector. * * * UPDATE FROM TOM BYYKKONEN TO PETE SNYDER ON 4/8/10 AT 2025 * * * Based on further evaluation, Salem officially notified the New Jersey Department of Environmental Protection of the above tritium spill on 4/8/10 at 2003. This notification to New Jersey is reportable in accordance with 10 CFR 50.72(b)(2)(xi). The licensee notified the NRC Resident Inspector. Notified R1DO (Trapp). |