Semantic search
| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 56501 | 2 May 2023 19:00:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Loss of Communications | The following information was provided by the licensee via email: At approximately 1500 (EDT) on 5/2/2023, it was determined that the commercial telecommunications capacity was lost to the Palisades Nuclear Plant (PNP) control room and technical support center due to an issue with the telecommunications provider. After discovery of the condition it was discovered that this loss also included the emergency notification system (ENS). Communications link via the satellite phone was tested satisfactorly. In addition, if needed, the satellite phone would be used to initiate call-out of the emergency response organization. The condition did not affect the ENS or commercial telecommunications capabilities at the offsite Emergency Operations Facility. The telecommunications provider has not provided an estimated repair time. PNP will be notifying the NRC resident inspector.
The following information was provided by the licensee via email: This notification is being made to retract event EN 56501 that was reported on May 02, 2023. Based on further investigation, the Emergency Plan and Emergency Implementing Procedures provide an acceptable alternative routine communication system, which is satellite phones, for communicating with Federal, State, and local offsite agencies, that are in addition to the primary commercial telephone system. It was determined that no actual or potential loss of offsite communications capability existed per 10 CFR 50.72(b)(3)(xiii). This is consistent with NUREG 1022, Revision 3, Supplement 1, 'Event Report Guidelines 10 CFR 50.72(b)(3)(xiii),' and NEI 13-01, Revision 0, 'Reportable Action Levels for Loss of Emergency Preparedness Capabilities.' The NRC Decommissioning Inspector has been notified of the retraction. Commercial telecommunications to the plant were restored at approximately 0600 EDT on 5/3/2023. Notified R3DO (Orlikowski) | ||
| ENS 49924 | 17 March 2014 18:18:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Displayed Meteorological Data Potentially Inaccurate | At 1418 EDT on 03/17/2014, it was determined the atmospheric stability classification data display on the plant process computer (PPC) could have been potentially inaccurate. In September 2012, implementation of a hardware and software modification to separate the meteorological tower computer from the PPC introduced a calculation error to the PPC software design that resulted in the PPC potentially displaying inaccurate stability class data. The ability to accurately perform dose assessment calculations could potentially be affected when using the stability class indication obtained from the PPC. The availability and accuracy of backup stability class data via the meteorological tower computer or from Weather Services International were not affected. Within 24 hours of discovery, the procedurally described alternatives for obtaining stability class data were implemented. Subsequently, the PPC stability class software calculation was corrected and the PPC stability class display restored for use. There was no impact to any emergency declaration because there were no actual emergencies from the time the modification was implemented until the error was corrected. The licensee has notified the NRC Resident Inspector. | ||
| ENS 44745 | 29 December 2008 11:15:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Loss of Ens and Commercial Phone Service | At approximately 0615 on December 29, 2008, it was determined that the Emergency Notification System (ENS) and commercial telecommunications capability were out of service. The condition impacts both the Control Room and the Technical Support Center. The problem has been determined to be an offsite issue with the telecommunications provider. Immediately after discovery of the condition, communications capability via satellite phone was tested and established between the Palisades Control Room and the NRC Operations Center. In addition, if needed, the satellite phone will be used to initiate call-out of the emergency response organization and to contact the regional load dispatcher. This condition did not affect the ENS or commercial capabilities at the offsite Emergency Operations Facility. The telecommunications provider has not provided an estimated repair time. The licensee notified the NRC Resident Inspector.
The telecommunications provider restored full ENS and commercial telecommunications capability to the Palisades Nuclear Plant at approximately 2100 EST. The condition was caused by an offsite fiber-optic cable that had been accidentally severed. The licensee notified the NRC Resident Inspector. Notified the R3DO (Cameron). | ||
| ENS 43594 | 24 August 2007 23:57:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Partial Loss of Process Computer Parameters to Erds | A portion of the Palisades Plant Process Computer (PPC) including a significant number or Emergency Response Data System (ERDS) trended input became inoperable due to a host computer failure. The cause of the host computer failure is unknown. Necessary redundant control room parameters exist and are functioning. Palisades is currently in no associated Technical Specification LCOs. Repair of the host computer will be prudently pursued. NRC notification of repair completion will occur. The licensee notified the NRC Resident Inspector. * * * UPDATE AT 2005 ON 8/26/07 FROM MULFORD TO SNYDER * * * The licensee restored the host computer at 1757 on 8/26/07 so it is now providing accurate data. The licensee notified the NRC Resident Inspector. Notified R3DO (Lara). | Emergency Response Data System | |
| ENS 42053 | 12 October 2005 21:09:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Partial Loss of Plant Process Computer | Portions of the Palisades Plant Process Computer (PPC) including the Emergency Response Data System (ERDS) became inoperable due to failure of a plant inverter (EY-210). The failed inverter supplies power to portions of the PPC. The inverter failed for unknown reasons. Options for bypassing the inverter and inverter repairs are being evaluated. The licensee notified the NRC Resident Inspector.
At 0500 the Palisades Plant Process Computer (PPC) including ERDS was declared operable after bypassing plant inverter EY-210 per plant procedure and restoring power to equipment. The licensee notified the NRC Resident Inspector. | Emergency Response Data System |