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| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 49960 | 8 February 2014 04:19:00 | 10 CFR 50.73(a)(1), Submit an LER | Invalid Actuation of a Containment Isolation Signal | This 60-day telephone notification is being made in accordance with 10 CFR 50.73(a)(2)(iv)(A) to provide information pertaining to the invalid actuation of a containment isolation signal. On February 8, 2014, at 0019 (EST), with the plant in Mode 6 and fuel moves in-progress, an invalid containment isolation actuation signal was generated that affected containment isolation valves in more than one system and caused both trains of the control room heating, ventilation and cooling systems to swap from normal to emergency mode of operation. For both occurrences, all necessary follow-up actions were taken in accordance with the abnormal operating procedure for a spurious containment isolation event. All equipment responded in accordance with the plant design. The invalid actuation signal was caused by spurious upscale spikes in fuel handling area radiation monitor, RIA-2316. Actual radiation levels in the vicinity of RIA-2316 were verified to be normal and below the alarm set point. The indication on RIA-2316 spiked momentarily above the high alarm set point and then returned to normal levels. No alarms were received from the redundant fuel handling area radiation monitor, RIA-2317. The NRC Resident Inspector has been notified. | ||
| ENS 49959 | 6 February 2014 15:43:00 | 10 CFR 50.73(a)(1), Submit an LER | Invalid Actuation of a Containment Isolation Signal | This 60-day telephone notification is being made in accordance with 10 CFR 50.73(a)(2)(iv)(A) to provide information pertaining to the invalid actuation of a containment isolation signal. On February 6, 2014, at 1143 (EST), with the plant in Mode 6 and fuel moves in-progress, an invalid containment isolation actuation signal was generated that affected containment isolation valves in more than one system and caused both trains of the control room heating, ventilation and cooling systems to swap from normal to emergency mode of operation. For both occurrences, all necessary follow-up actions were taken in accordance with the abnormal operating procedure for a spurious containment isolation event. All equipment responded in accordance with the plant design. The invalid actuation signal was caused by spurious upscale spikes in fuel handling area radiation monitor, RIA-2316. Actual radiation levels in the vicinity of RIA-2316 were verified to be normal and below the alarm set point. The indication on RIA-2316 spiked momentarily above the high alarm set point and then returned to normal levels. No alarms were received from the redundant fuel handling area radiation monitor, RIA-2317. The NRC Resident Inspector has been notified. | ||
| ENS 42317 | 14 December 2005 11:16:00 | 10 CFR 50.73(a)(1), Submit an LER | Invalid System Actuation of Emergency Core Cooling System Components | This report is being made in accordance with 10 CFR 50.73(a)(1), which states in part, 'in the case of an invalid actuation reported under 10 CFR 50.73(a)(2)(iv), other than the reactor protection system (RPS) when the reactor is critical, the licensee may, at its option, provide a telephone notification to the NRC Operations Center within 60 days after discovery of the event instead of submitting a written LER. On December 14, 2005, at 0616 hours EST, a failure of the left channel load sequencer resulted in an invalid actuation of components associated with the left channel design basis accident (DBA) sequencer. Components in the emergency core cooling system were among the components actuated. Therefore, this event constitutes a partial actuation of the emergency core cooling system, which is reportable under 10 CFR 50.73(a)(2)(iv)(A). All components actuated by the event functioned satisfactorily as would be expected for this equipment failure and operating status of the plant at the time of the event. The licensee notified the NRC Resident Inspector. | Reactor Protection System Emergency Core Cooling System | |
| ENS 41263 | 4 November 2004 14:17:00 | 10 CFR 50.73(a)(1), Submit an LER | Invalid System Actuation - Safety Injection | On November 4, 2004, at 0917 hours EST, an inadvertent actuation of the left train of the safety injection system was initiated. The invalid actuation occurred during a system surveillance test, when a screwdriver that was being used to lift a lead slipped, causing a short circuit between the terminal being disconnected, and an energized terminal directly in front of it. As a result, all left train safety injection system equipment activated as expected for existing plant conditions. The resident inspector was notified of this event. |