Semantic search
| Entered date | Event description | |
|---|---|---|
| ENS 49740 | 18 January 2014 05:56:00 | At 0346 CST (the Unit 1 control room) received a fire alarm in the plant computer room. Upon investigation (the licensee) discovered (the plant computer) room with heavy smoke present and the halon system actuated. (Plant operators) entered '0P0P04-ZO-0008, Fire and Explosion'. Entered Unusual Event at 0401 CST. Fire brigade present at Unit 1 electrical auxiliary building. At 0412 CST the fire was declared to be under control with no visible signs of flame noticed by the fire brigade. Unusual Event based on HU2 (fire or explosion) in the (Protected Area or Switchyard) which affects normal plant operations." At 0446 CST the fire was declared to be extinguished. No plant equipment or indications were affected. The licensee has notified the NRC Resident Inspector, the State of Texas, and other local authorities. Notified DHS SWO, FEMA Operations Center, NICC Watch Officer, and NuclearSSA via e-mail.
At 0957 EST, (on 1/18/14, the) Unusual Event (was) terminated. Fire damage assessment not complete. Working with site engineering, fire protection, and maintenance personnel to restore all fire detection and protection systems. Continuous fire watch being maintained. Priority is to restore fire detection and protection systems to affected area, followed by repairs to damaged equipment. The licensee has notified the NRC Resident Inspector, the State of Texas, and other local authorities. Notified R4DO (Keller), NRR (Uhle), R4RA (Dapas), NRR EO (Lee), and IRD MOC (Grant). Notified DHS SWO, FEMA Operations Center, NICC Watch Officer, and NuclearSSA via e-mail. |
| ENS 46387 | 3 November 2010 12:09:00 | On November 3, 2010 at 1021 CDT, operators attempted to start the Unit 2 startup feedpump to support a two hour maintenance run. The feeder breaker for the startup feedpump exploded causing an undervoltage condition on Auxiliary Bus 1H and Standby Bus 1H which resulted in an automatic reactor trip due to reactor coolant pump undervoltage. All control rods inserted into the core. At 1038 CDT, the site declared an UNUSUAL EVENT (HU-2) due to an explosion in the protected area which affects normal plant operations. The standby diesel generator (EDG-23) started and loaded to the 'C' train loads which sequenced properly. The auxiliary feedwater system automatically started as expected providing feedwater to the steam generators. The normal feedwater pumps were secured. Decay heat is being removed from Unit 2 using the normal steam dump valves to the main condenser. There is no primary to secondary leakage. The plant is stable and in MODE 3 with no challenges to reactor safety. There was no impact on Unit 1. At 1240 CDT the licensee terminated the UNUSUAL EVENT. The licensee is investigating the cause of the breaker explosion and if the other standby diesel generator (EDG-21) should have started due to the undervoltage condition. The licensee notified the NRC Resident Inspector.
A News Release is being planned so this condition is also being reported pursuant to 10 CFR 50.72(b)(2)(xi). During the electrical fault condition, some Train A components stopped running although no Train A low voltage ESF actuation occurred, The reason for this occurrence is not fully understood, The breaker malfunction did not result in a fire. The licensee will notify the NRC Resident Inspector. Notified: R4DO (Spitzberg); NRR (Thorp); R4RA (Collins); NRR (Boger); IRD (Gott) DHS (Hill); FEMA (Hollis)
The licensee called to correct an editorial error in the original report above. The second sentence of the original report above should refer to Auxiliary Bus 2H and Standby Bus 2H since this is a Unit 2 issue. Notified: R4DO (Spitzberg). |