Semantic search
| Entered date | Event description | |
|---|---|---|
| ENS 56091 | 6 September 2022 03:00:00 | The following information was provided by the licensee via email: At 2345 CDT, Unit 1 Reactor tripped due to a turbine trip. All auxiliary feedwater pumps started due to steam generator Lo Lo levels. Unit 1 is being maintained in Hot Standby (Mode 3) in accordance with Integrated Plant Operating Procedure IPO-007A. The Emergency Response Guideline procedure has been exited. Decay heat is being rejected to the main condenser via steam dump valves. The cause of the Turbine Trip is currently under investigation. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: NRC Resident Inspector has been notified. Unit 2 is unaffected by this event. |
| ENS 53423 | 23 May 2018 16:10:00 | At time 0848 (CDT), Main Steamline Radiation Monitor 2-RE-2328 (Main Steamline 2-04) lost communications and was declared non-functional. With this radiation monitor non-functional, all of the emergency action levels for a steam generator tube rupture in steam generator 2-04 could neither be evaluated nor monitored. This unplanned condition is reportable as a loss of assessment capability per 10CFR50.72(b)(3)(xiii). Comanche Peak Nuclear Power Plant (CPNPP) has assurance of steam generator integrity and fuel cladding integrity and there is a negligible safety significance to the current condition from a public health and safety perspective. Additionally, compensatory measures are in place to assure adequate monitoring capability is available to implement the CPNPP emergency plan in the unlikely event of challenges to the steam generator or fuel cladding. The N16 radiation monitor serves as a backup with alarm function and Radiation Protection technicians have been briefed on taking local readings with a Geiger-Mueller tube on MSL 2-04. Corrective actions are being pursued to restore 2-RE-2328 to a functional status. The NRC Resident Inspector has been notified. |
| ENS 53380 | 3 May 2018 18:40:00 | During planned maintenance on Unit 2 Radiation Monitor 2-RE-4270 (Service Water Train B to Discharge Canal Rad Monitor), at 1220 CDT, several other Unit 2 Radiation Monitors that are used for Emergency Action Level evaluation became nonfunctional for about 1 hour. With these radiation monitors non-functional, all of the Emergency Action Levels associated with these monitors could neither be evaluated nor monitored. This unplanned condition is reportable as a loss of assessment capability per 10 CFR 50.72(b)(3)(xiii). A PC11 computer reboot restored the affected radiation monitors to a functional status. The NRC Resident Inspector has been notified. |
| ENS 53143 | 2 January 2018 17:17:00 | At 1137 CST on January 2, 2018, Comanche Peak Nuclear Power Plant (CPNPP) Unit 2 experienced an unplanned loss of the Plant Computer System (PCS). The loss of the Unit 2 PCS resulted in a loss of emergency assessment capability to the CPNPP Technical Support Center (TSC) and Emergency Operations Facility (EOF) for greater than 60 minutes. This report is being made pursuant to 10 CFR 50.72(b)(3)(xiii), any event that results in a loss of emergency assessment capability, off-site response capability, or off-site communications ability. The NRC Resident Inspector has been informed. Repairs are on-going. |