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| Entered date | Event description | |
|---|---|---|
| ENS 52414 | 7 December 2016 17:24:00 | During the evaluation of tornado missile vulnerabilities and the potential impacts to Technical Specification (TS) plant equipment, it was concluded that the following SSCs (systems, structures, and components) were vulnerable to tornado generated missiles. The Service Water Intake Structure (SWIS) intake and exhaust ventilation hoods, located on the roof of the SWIS, are not adequately protected from missiles generated by a tornado. Should a tornado-generated missile strike the SWIS intake and exhaust ventilation hoods, the hoods could crimp thus reducing air flow and challenging the performance of their heating and cooling safety functions. If the intake hoods were damaged or removed due to a missile strike, entry of rainwater could occur due to severe weather high wind velocity, and could affect safety related electrical equipment in the rooms directly below the hoods. These potential conditions could render Service Water trains inoperable on either or both units. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B) for any event or condition that results in the nuclear power plant being in an unanalyzed condition that significantly degrades plant safety, and per 10 CFR 50.72(b)(3)(v)(D) for any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident. This condition is being addressed in accordance with EGM-15-002 and DSS-ISG-2016-01 (enforcement discretion and interim guidance documents). Required actions have been taken. Corrective actions will be documented in a follow up licensee event report. The NRC Resident Inspector will be notified. The licensee is evaluating the operability of the service water system. Should one train be declared inoperable, the licensee would be in a 72 hr. LCO action statement. If both trains are inoperable, then the licensee would enter T.S. 3.0.3. |
| ENS 52374 | 17 November 2016 20:51:00 | At 1859 CST on November 17, 2016, Farley Nuclear Plant Unit 1 initiated a shutdown from approximately 99 percent reactor power. The shutdown was initiated per Technical Specification LCO 3.0.3. This LCO entry was based on having no operable steam flow channels on the C loop for Farley Nuclear Plant Unit 1. Unit 2 as not affected. The NRC Resident Inspector has been notified. |
| ENS 48140 | 26 July 2012 23:24:00 | At 21:51 (CDT) (on 7/26/12), Farley has commenced shutdown of Unit 1 in accordance with T.S. 3.8.1, AC Sources - Operating. 1B Diesel Generator was removed from service on 7/16 at 21:52 (CDT) for a planned 24 month outage. Due to emergent equipment issues with the diesel, the RAS (Required Action Statement) time of 10 days to return the diesel generator to service has not been met. Unit 1 shutdown to Mode 3 has commenced. The unit must be in Mode 3 by 03:52 (CDT) on 7/27/12, and Mode 5 by 09:52 (CDT) on 7/28/12. The licensee has informed the NRC Resident Inspector. |
| ENS 42674 | 30 June 2006 09:43:00 | (On June 30, 2006 the licensee initiated) a plant shutdown required by Technical Specifications. (The licensee) discovered during surveillance testing, that the Unit 1 Main Steam Isolation Valve (MSIV-3370B) for the B-loop, would not return to the fully open condition after the partial stroke test. The valve appeared to stroke smoothly to the test position. Trouble shooting of the condition has not determined the exact cause however it appears that there is possible binding. The licensee has tried reasonable methods to free the valve but was unable to do so. The licensee declared the MSIV inoperable. The plant's Technical Specifications require a shutdown within 72 hours with one MSIV inoperable. The licensee has no other safety significant limiting conditions for operation in effect. The safety related electrical buses are powered from offsite power and the grid is stable in the area. The licensee notified the NRC Resident Inspector. |
| ENS 42280 | 20 January 2006 17:07:00 | The Public Prompt Notification System sirens were inoperable from 10:17 CST until 11:36 CST on 01/20/06. (They were inoperable for) a period of one hour and 19 minutes. The siren system was returned to operation when the antennae for operating the sirens was changed. The Tone Alert Radio System was operational during this entire time period and remains operable. The cause of the failure is not clearly understood at this time. The appropriate test equipment is being sent to the site and a complete troubleshooting plan with a test plan will be started on Monday 01/23/06. Until that time a contingency plan is in place that has personnel on call that will report to the three siren sites if an emergency is declared. They will be in communications with the local authorities to activate the sirens locally in accordance with an approved plant procedure. While performing the troubleshooting and maintenance on the siren system we will have staff standing by at the sirens that will be able to activate the sirens in accordance with an approved plant procedure. The licensee will notify the NRC Resident Inspector. |