Semantic search
| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 53934 | 15 March 2019 10:46:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | En Revision Imported Date 3/25/2019 | EN Revision Text: UNUSUAL EVENT DECLARED DUE TO HIGH RIVER LEVEL At 0546 CDT, Cooper Nuclear Station declared an Unusual Event due to the Missouri River level reaching 899.05 feet above mean sea level (MSL), which is above the Emergency Action Level (EAL) HU 1.5 elevation of 899 feet above MSL. The river is expected to crest above 901 feet above MSL within the next day, and remain above 899 feet above MSL for the next several days. Declaration of an Unusual Event is a 1 hour report, and is reportable under 10 CFR 50.72.a.1.1. Actions are in progress in accordance with site flooding procedure, including strategic placement of barriers at building entrances and important facilities. There is no major plant equipment out of service at this time. Personnel access to the site is not presently impeded and emergency evacuation routes remain available. A press release is planned for this event, which is a four hour report, reportable under 10 CFR 50.72.b.2.11. If the Missouri River were to reach 901.5 feet above MSL, Cooper would initiate a unit shutdown in accordance with their procedures. If the Missouri River were to rise greater than 902 feet above MSL, Cooper will declare an Alert. The licensee notified the NRC Resident Inspector. Notified DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).
The licensee terminated the Unusual Event at 1601 CDT due to lowering Missouri River water levels. River water level is currently at 896.0 feet MSL and lowering. A press release will be issued to inform the public of Cooper Nuclear Station's exit from the Notification of Unusual Event regarding high Missouri River level. The initial entry into the Notification of Unusual Event occurred on 03/15/2019 and was exited on 03/24/2019 at 1601 CDT. The press release is reportable per 10 CFR 50.72(b)(2)(xi). The licensee notified the NRC Resident Inspector. Notified R4DO (O'Keefe), NRR EO (Miller), IRD MOC (Gott), DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email). | ||
| ENS 53809 | 29 December 2018 06:00:00 | 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Notice of Unusual Event Due to Toxic Gas and Fire | At 0904 CST, on December 29, 2018, Cooper declared a Notice of Unusual Event under emergency action level HU 3.1. The emergency declaration was due to a toxic gas asphyxiant as a result of a fire. The fire is contained and the fire brigade continues to extinguishing the fire. Offsite support has not been requested. The licensee notified the NRC Resident Inspector. Additionally, State and Local government agencies were also notified. Notified DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).
At 1544 CST, on December 29, 2018, Cooper terminated the Notice of Unusual Event under emergency action level HU 3.1. The fire was verified to be extinguished and the flammable material was removed. The plant remained at 100% power for the duration of the event. The licensee issued a press release regarding the event at 1202 CST, on December 29, 2018. The license notified the NRC Resident Inspector. Notified R4DO (Taylor), NRR EO (Groom), IRD MOC (Gott), DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email). | ||
| ENS 53069 | 14 November 2017 17:18:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event Declared Due to Hydrogen Line Leak | At 1118 CST on 11/14/17, Cooper Nuclear Generating Station declared an Unusual Event due to a hydrogen leak on a main generator purge line. The leak was reported to be caused by Maintenance cutting into a one inch line. The total size of the leak is unknown, however, it is estimated to be depressurizing in the main generator at approximately 1lb per hour. The current pressure is 52 to 53 lbs. pressure and is stable. The operations staff have entered their abnormal procedure and are taking actions to isolate the leak. Operators have isolated the source of hydrogen and have opened the exterior roll up doors to increase the airflow and minimize the concentration of hydrogen in the area. The area has been evacuated and hot work has been stopped. The NRC Resident Inspector has been notified. Notified DHS, FEMA, NICC and NNSA (via email).
On 11/14/2017, Nebraska Public Power District will issue a press release concerning the declaration of a Notification of Unusual Event (EN#53069) declared today at 1118 (CST) for a small hydrogen leak in the turbine building. This is a four hour report per 10CFR50.72(b)(2)(xi) for any event or situation for which a news release is planned or notification to other government agencies has been or will be made which is related to heightened public or government concern. Notified the R4DO (Kozal).
At 1744 CST the licensee exited from the Unusual Event. The leak was patched under a temporary repair. The patch was tested to verify the leak has stopped. The NRC Resident Inspector was notified. Notified the R4DO (Kozal), IRDMOC (Gott), NRR EO (Miller), DHS, FEMA, NICC and NNSA (via email). | ||
| ENS 52221 | 3 September 2016 12:10:00 | 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event Declared Due to Seismic Event Alarm | At 0710 CDT, Cooper Nuclear Station declared a Notification of Unusual Event under EAL HU1.1 due to the station seismic event alarm registering a response to an earthquake (epicenter near Pawnee, OK). The reactor was not affected by the earthquake and remains at 93 percent power. The licensee is performing walkdowns of structures and equipment to verify that the site is unaffected. Notified the DHS SWO, FEMA Ops Center, DHS NICC, FEMA National Watch Center (E-mail) and Nuclear SSA (E-mail).
At 1547 CDT, Cooper Nuclear Station terminated the Notice of Unusual Event. All inspections and walkdowns of the plant have been completed. No damage or injuries were reported. The seismic event caused no impact to the plant. The Licensee has notified the NRC Resident Inspector. Notified R1DO (Warnick), NRR EO (Miller), IRDMOC (Stapleton), DHS SWO, FEMA Ops Center, DHS NICC, FEMA National Watch Center (E-mail) and Nuclear SSA (E-mail). | ||
| ENS 47760 | 22 March 2012 15:34:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Notice of Unusual Event - Potentially Hazardous Atmosphere Due to Freon Leak | At 1034 CDT on 3/22/12, Cooper Nuclear Station declared a Notice of Unusual Event due to a freon leak from a glycol compressor in the sub-basement of their Augmented Radwaste Building. This created a potentially unsafe localized atmosphere in that area per Emergency Action Level HU 3.1. The licensee made a public address system announcement to avoid the area and sent personnel to guard the area to prevent entry. The licensee is monitoring the area for any deterioration. Oxygen levels are currently normal. Cooper Nuclear Station personnel plan to isolate the freon leak and ventilate the area to ensure a habitable atmosphere. There are no safety related systems or components in the affected area. Plant operation is unaffected. As of 1045 CDT, the licensee has notified appropriate state and local governmental agencies. The licensee notified the NRC Resident Inspector. Notified DHS SWO, DHS NICC, FEMA and Nuclear SSA via email. * * * UPDATE AT 1320 EDT ON 3/22/12 FROM ROBERT LECHNER TO PETE SNYDER * * * Cooper Nuclear Station personnel monitored the atmosphere in the affected area for safe entry then entered and isolated the freon leak. They did further extensive monitoring for any pockets of trapped freon gas and further ventilated the area to restore the area to a habitable condition. At 1142 CDT Cooper Nuclear Station exited their Unusual Event condition. Offisite notifications were made per 10 CFR 50.72 (b)(2)(xi). A press release is planned to inform the public of this onsite event. Notified DHS SWO, DHS NICC, FEMA and Nuclear SSA via email | ||
| ENS 46969 | 19 June 2011 09:02:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event Declared Due to Missouri River Flooding | At 0402 CDT on 6/19/2011 a Notification of Unusual Event was declared due to the elevation of the Missouri River reaching 899.1 feet above mean sea level. This is above the Emergency Action Level HU1.5 elevation of 899 feet. The Missouri River is expected to crest at 899.5 feet within the next couple of days. It is expected that the elevation of the Missouri River will remain above 899 feet for most of the summer. Actions are in progress in accordance with the site flooding procedure, including strategic placement of sand bags at building entrances and important facilities. There is no major plant equipment out of service at this time. Personnel access to the site is not presently impeded. Emergency evacuation routes remain available. The licensee notified the NRC Resident Inspector. The licensee notified the State of Nebraska Emergency Management Agency, the State of Missouri State Emergency Management Agency, the Nemaha County Emergency Operations Center, the Richardson County Emergency Operations Center and the Atchison County Emergency Operations Center.
On 6/19/2011 at 0447 CDT, Nebraska Public Power District issued a press release concerning the declaration of a Notification of Unusual Event declared today at 0402 for the Missouri River elevation above 899 feet above sea level. This is a four hour report per 10CFR50.72(b)(2)(xi) for any event or situation for which a news release is planned or notification to other government agencies has been or will be made which is related to heightened public or government concern. State and local agencies were notified of the expected news release during the NOUE notification. At 0402 CDT, Missouri River elevation was at 899.1 feet. No updated river projections are available at this time. Level is expected to remain at least below plant grade elevation. No deficiencies with the nearby protective levees have been identified surrounding the plant. Actions are in progress in accordance with the site flooding procedure, including strategic placement of sandbags at building entrances and important facilities. Personnel access to the site is not presently impeded, and required emergency evacuation routes remain available. The licensee notified the NRC Resident Inspector. Notified R4DO (Werner).
Cooper Nuclear Station exited the Notification of Unusual Event (NOUE) at 0947 CDT on 7/12/11. River level is currently at 895.8 feet MSL which is below the NOUE threshold of 899 feet MSL. River level is forecast to continue going down. The licensee is expecting to issue a press release today. The licensee notified the NRC Resident Inspector, State of Missouri, Nebraska Emergency Management Agency, Nemaha County Sheriff, Richardson County Sheriff, Missouri FEMA, and the Atchison County 911 center. Notified the R4DO (Cain), IRD (Morris), NRR (Thorpe), DHS (Strangfeld), and FEMA (Hollis).
A press release has been issued to inform the public of Cooper Nuclear Station's exit from the Notification of Unusual Event, regarding high Missouri River level. The initial entry into the Notification of Unusual Event occurred on 06/19/2011 and was exited on 07/12/2011. The highest river level observed at (Cooper) was 900'-8". Plant grade is at 903'-6". The press release reports the current Missouri river level as 895.8' and forecasted to continue to lower. Notified the R4DO(Cain). | ||
| ENS 46033 | 22 June 2010 07:06:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | River Water Level Above 899 Feet | River water level exceeded 899 feet above sea level resulting in the licensee declaring a Notice of Unusual Event at 0206 CDT. The plant continues to operate at 100 percent power. The licensee notified the NRC Resident Inspector. * * * UPDATE FROM BARTON CROW TO JOE O'HARA AT 1042 ON 6/22/10 * * * On 6/22/10 at 0557 Cooper Nuclear Station made a news release concerning the 'Notification of Unusual Event' declared today at 0206 for Missouri River level at 899 feet above sea level. This is a 4 hour report per 10CFR50.72(b)(2)(xi) for any event or situation for which a news release has been made that causes heightened public or government concern. State and local agencies were notified by the 'Notification of Unusual Event' declaration. At 0900 CDT Missouri River level was at 899.35 feet above sea level. The licensee notified the NRC Resident Inspector.
The Unusual Event was terminated at 1513 CDT. The Missouri River level was at 897.3 feet above sea level and receding. The licensee notified the NRC Resident Inspector, the State, local, and other government agencies. Notified the R1DO (Pick), NRR EO (Cunningham), IRD (Morris), DHS (An), and FEMA (Barden). | ||
| ENS 45428 | 12 October 2009 21:03:00 | 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Notification of Unusual Event Due to Small Fire Lasting Greater than 10 Minutes | At 1551, (the control room) received a 911 notification of a fire in the Condenser area. Entered abnormal procedure 5.1 Incident (and the) fire brigade was dispatched. Follow-up reports indicated that the fire was in the Heater Bay area in the vicinity of B2/B3 heaters. 'At 1556, the Control Room received a report via the Work Control Center from a qualified fire watch on the scene that the fire had been extinguished. At 1603 the Emergency Director declared a NOUE, on EAL 5.1.1, due to a fire in the Protected Area that takes longer than 10 minutes to extinguish. At the time of the declaration, a six sided search had not yet been conducted in accordance with procedural requirements. At 1613, the Fire Brigade Leader reported a six sided search of the Heater Bay area was complete, and the fire was declared OUT. At 1619 the 'all clear' alarm sounded. At 1638, the Emergency Director terminated the NOUE. The actual location of the fire was in a pipe chase between B-4 and B-3 Heaters and was caused by hot ceramic pellets from a heating blanket that was above the area of the location of the fire. The heating blankets were being used to pre-heat the piping in preparation for welding. A pigtail that feeds the blanket failed and some of the hot ceramic pellets from inside the blanket dropped down on to the plastic protecting the area below from foreign materials. The hot ceramic pellets on the plastic caused a small (approx. 3 inch diameter) fire. The active fire only lasted for approximately five minutes. All required notification were completed in a timely manner. The licensee notified the NRC Resident Inspector. | ||
| ENS 42985 | 11 November 2006 11:30:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event Declared Due to an Electrical Fire Involving Heat Trace | At 0530 CST, CNS declared an Unusual Event per EAL 5.1.1 "Any fire within the Protected Area which takes longer than 10 minutes to extinguish," due to a fire involving the Standby Liquid Control (SLC) heat tracing. Operators in the control room received a report from the Refueling Floor that heat trace installed on piping of the SLC System in Reactor Building 976 East was "arcing & sparking." Responders on-scene extinguished the fire after de-energizing the heat trace by opening the associated electrical feeder breaker. All personnel are accounted for and there are no reported injuries. The licensee will conduct a comprehensive review to determine the extent of damage. The SLC System is a TS required safety system but is not required for current plant conditions. No other safety-related equipment was affected. The licensee is not augmenting staff in response to this event and no offsite assistance was requested. The licensee informed State and local agencies and the NRC Resident Inspector who is enroute to the site.
The licensee terminated the Unusual Event at 0558 CST on 11/11/06 based on the judgment of Station Management since the extent of condition is well understood, the affected electrical circuit is isolated and that no reflash watch is necessary. The licensee informed State and local agencies and the NRC Resident Inspector. Notified R4DO (Clark), EO (Bateman), IRD (Wilson), DHS (Gomez) and FEMA (Sweetser).
The licensee will be issuing a press release regarding this incident and has informed the NRC Resident Inspector. Notified R4DO (Clark). | Standby Liquid Control | |
| ENS 42728 | 25 July 2006 20:41:00 | 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event Declared Due to Fire Alarm | Cooper Nuclear Station control room received a fire alarm at 1529 CST indicating a fire in the service water pump room. The licensee responded by dispatching a fire brigade to the service water pump room to investigate. At 1541 CST, the licensee declared an unusual event in accordance with their emergency procedures due to their inability to confirm the validity of the fire alarm within a 10 minute period. The licensee exited the unusual event at 1559 CST after determining that the alarm was a false alarm caused by welding inside the service water pump room. The licensee issued a press release. The licensee notified the NRC Resident Inspector, the Nebraska State Patrol, the Richardson County Sheriff's Office, Nemaha County Sheriff's Office, Missouri Highway Patrol, and the Atchison County 911 Center. | Service water | |
| ENS 42466 | 2 April 2006 19:04:00 | 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event Declared Due to Adverse Weather Conditions | An Unusual Event was declared per EAL 7.1.4 at 1404 CDT due to strong winds exceeding 74 mph onsite for 5 minutes between 1355-1400 CDT (peak windspeed measured at 83 mph). The Unit remained at 100% power during the incident. Current plant conditions are stable with windspeed approximately 30 mph. Offsite power is stable with a surveillance of the #1 EDG in progress. After completion of walkdowns the licensee will assess exiting the Unusual Event. A preliminary damage report indicated loose guy wire(s) on the met tower. The licensee informed state/local agencies and the NRC Resident Inspector who is onsite.
The licensee terminated the Unusual Event at 1500 CDT based on current sustained windspeeds less than 74 mph and passage of the storm front. The licensee is continuing their damage assessment walkdowns. The licensee informed state/local agencies and the NRC Resident Inspector. Notified R4DO (Powers), EO (Gillespie), IRD (Wilson), DHS (Mitchell), and FEMA (Mick Roland). | ||
| ENS 42431 | 20 March 2006 13:56:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event Declared Due to Small Fire Inside Protected Area | Fire inside the Protected Area lasting greater than 10 minutes in an electrical conduit between the Ionic trailer and the Water Treatment Building. Power to the electrical feed through the conduit to the Ionic trailer has been secured. No offsite assistance has been requested. The licensee is verifying the status of the fire after securing the power. The licensee notified the NRC Resident Inspector and the State and Local authorities.
Fire was declared out at 0842 CST. Fire was in the EE transformer supplying the Ionic trailer. Fire was extinguished by opening Breaker 48D. The licensee corporate office will be issuing a press release later today. The licensee notified the NRC Resident Inspector.
Licensee terminated the Unusual Event due to the fire being out and plant returned to normal operation with the exception of the Ionic trailer power. The licensee notified the NRC Resident Inspector. Notified R4DO (Clark), NRR EO (Benner), IRD Manager (McGinty), DHS (Everette) and FEMA (Liggett) | ||
| ENS 40254 | 16 October 2003 17:30:00 | 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Unusual Event at Cooper Due to Small Fire at a Turbine Bearing | The licensee declared an Unusual Event at 12:30 CDT pertaining to a small fire, located at the high pressure turbine number 1 bearing, which was burning greater than 10 minutes. There were no injuries and the turbine continues to operate at full power while the fire brigade attempts to extinguish the fire. Subsequently, the licensee extinguished the fire; however, several minutes later, the fire restarted. The licensee decided to lower power to approximately 65% power to lower general area radiation levels for the fire brigade personnel. The fire was extinguished and reflashed a few times. The fire brigade used water, dry chemicals and foam when fighting the fire. The source of the fire at the bearing is under investigation by the licensee.
The licensee reports that the fire is out and the investigation determined that the most likely source of the fire was oil pooled under the bearing pedestal. No current oil leakage was found. The licensee planned on contacting the turbine vendor prior to returning the plant to full power. The Unusual Event was terminated at 1541 CDT. Notified R4DO (G. Sanborn), DIRO (D. Weaver), NRR EO (T. Reis), DHS (J. Clardy) and FEMA (J. Dunker). |