Semantic search
| Entered date | Event description | |
|---|---|---|
| ENS 49838 | 18 February 2014 13:18:00 | At 0944 CST, on February 18, 2014, both doors in the Secondary Containment Airlock were opened concurrently. The doors being open at the same time caused a failure to meet SR 3.6.1.4.2 to verify that either the outer door(s) or the inner door(s) in each Secondary Containment access opening are closed. The identified condition caused Secondary Containment to be considered inoperable per TS LCO 3.6.1.4. Upon discovery, immediate action was taken to close the doors. This action allowed SR 3.6.4.1.2 to be met, and restored Secondary Containment to operable status. This notification is being made pursuant to 10 CFR 50.72(b)(3)(v)(C). The NRC Resident Inspector has been notified. |
| ENS 47557 | 29 December 2011 10:59:00 | A planned maintenance evolution at the Duane Arnold Energy Center (DAEC) to replace power supplies in the plant process computer (Link 2) will result in a loss of some SPDS indications for a duration of less than 5 hours. No other indications or annunciators will be unavailable during this maintenance to affect the plant's ability to assess or monitor an accident of transient in progress. The licensee has notified the NRC Resident Inspector.
At 1006 CST on 12/29/11 the plant process computer (Link 2) was successfully restored and SPDS is functioning properly and returned to service. The licensee has notified the NRC Resident Inspector. Notified R3DO (Duncan). |
| ENS 45340 | 11 September 2009 12:40:00 | At 1100 on Friday, September 11, 2009 a portion of the Duane Arnold Energy Center power plant (DAEC) Technical Support Center (TSC) ventilation system, Technical Support Center (TSC) air conditioning system, and Technical Support Center (TSC) computer system was removed from service for maintenance on Technical Support Center (TSC) electrical power supply. The electrical power supply being removed supports air conditioning, filtration system and computers. Under certain accident conditions the TSC may become unavailable due to the inability of the ventilation system to maintain a habitable atmosphere and loss of computer systems. Compensatory measures exist to rapidly restore power to the TSC if necessary based upon TSC activation requirements. The TSC power supply maintenance is scheduled to complete at 1800 on Friday, September 11, 2009. The licensee has notified the NRC Senior Resident Inspector. This notification is being made in accordance with 10 CFR 50.72 (b) (3) (xiii) due to loss of an emergency response facility.
The TSC power supply maintenance has been completed and the Technical Support Center(TSC) is now fully available. The licensee will notify the NRC Resident Inspector. Notified the R3DO(Ring). |