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| Entered date | Event description | |
|---|---|---|
| ENS 51267 | 27 July 2015 16:05:00 | A licensed employee violated the site Fitness-for-Duty (FFD) policy. The employee's plant access has been denied. The NRC Resident Inspector has been informed. |
| ENS 50790 | 5 February 2015 20:47:00 | On January 27, 2015, during winter storm JUNO, there was a loss of instrument air at the Pilgrim Nuclear Power Station (PNPS). Follow-up evaluations of the plant events that occurred on that day revealed that the loss of instrument air resulted in a loss of water level indicators in the seawater intake bays. The affected instruments, LI-3831 A/B, are utilized in assessing conditions for entry into the Emergency Action Levels. PNPS Emergency Plan Implementing Procedure (EPIP) EP-IP-100.1 specified a compensatory action of 'visual inspection required' should these instruments be unavailable. However, there was not a clear linkage between the EPIP compensatory actions and the operations procedure for loss of instrument air. Neither the EPIP nor operations procedure identified the specific actions necessary to perform the local monitoring action. Based on the above, we have concluded that this event was reportable pursuant to 10CFR50.72(b)(3)(xiii), Any event that results in a major loss of emergency assessment capability. The review of the event revealed actual sea water levels in the intake bay did not meet plant specified EAL entry conditions at any time during the winter storm and therefore no plant equipment was impacted. The capability to assess intake bay water level locally in the intake bay was available. Subsequent to the winter storm event, the instrument air system and sea water bay level instrumentation were restored to service. Public health and safety were not adversely affected. The licensee has notified the NRC Senior Resident Inspector. The licensee will notify the Commonwealth of Massachusetts. |
| ENS 50769 | 27 January 2015 06:41:00 | On Tuesday January 27, 2015 at 0402 hours, with the Pilgrim Nuclear Power Station (PNPS) Reactor Mode Select Switch (RMSS) in Run and reactor power approximately 52% an automatic reactor scram signal was received due to the automatic trip of the main turbine that was initiated by the opening of the main generator breaker, ACB-104. The event occurred during winter storm 'Juno.' Prior to the event off-site transmission Line 355 was de-energized due (to) weather conditions and its associated PNPS switchyard breakers (ACB-105, a main generator breaker and ACB-102), were open. Per station procedures, reactor power was being lowered, a reactor protection system bus had been placed onto a back-up power supply, the Emergency Diesel Generators had been started and were powering the associated safety related 4 KV buses. The second off-site transmission Line 342 de-energized and the associated PNPS switchyard breakers (ACB-104 main generator breaker and ACB-103) opened. The Shutdown Transformer off-site power supply has remained available throughout this event. All control rods were verified to be fully inserted. Per plant design, Primary Containment Isolation System (PCIS) Group lI sampling systems, Group VI Reactor Water Clean-up (RWCU) system and Reactor Building Isolation System (RBIS) isolations occurred. Currently, the EDG's are powering the safety related 4KV buses, reactor water level is being maintained by the Reactor Core Isolation Cooling (RCIC) system and reactor pressure is being maintained by High Pressure Coolant Injection (HPCI) system. The station is conducting a plant cool down at this time. All systems responded as designed with the exception of a non-safety-related diesel air compressor, K-117 that failed to start. The licensee will notify the State and local governments and plans on issuing a press release. The NRC Resident Inspector has been informed. |
| ENS 50273 | 11 July 2014 15:28:00 | At 0823 EDT on Friday, July 11, 2014, the Pilgrim Nuclear Power Station (PNPS) determined that the plant process computer and, therefore, the in-plant Safety Parameter Display System (SPDS) was not functioning as designed due to a loss of power. The SPDS provides numerous plant parameters, some of which are credited for emergency assessment capability. The site has determined that this constitutes a major loss of assessment capability. Immediate actions were taken to restore the system to functional status and applicable plant procedures were entered to determine temporary mitigating actions. Power was subsequently restored at approximately 1030 EDT via an alternate supply, and SPDS has been restored to normal operation. This event had no impact on the health and/or safety of the public. This notification is conservatively being made in accordance with 10 CFR 50.72 (b)(3)(xiii). There is no impact to plant operations. The licensee notified the NRC Resident Inspector and will notify the State. |