Semantic search
| Entered date | Event description | |
|---|---|---|
| ENS 50743 | 19 January 2015 02:30:00 | At 2131 CST on January 18, the Duane Arnold Energy Center (DAEC) Technical Support Center (TSC) Normal Power was lost when a single phase to the T4 '36KV-12.5KV DAEC SITE TRANSFORMER' was lost due to a blown primary side fuse. Automatic power transfer occurred to maintain power to the TSC from the TSC Emergency Diesel Generator (EDG) which automatically started. The TSC remained functional throughout the incident. This notification is being made pursuant to 10 CFR 50.72(b)(3)(xiii) due to the loss of an emergency assessment capability. An update will be provided once the normal power supply has been restored. The licensee notified the NRC Resident Inspector.
Normal power restored to the TSC. The licensee notified the NRC Resident Inspector. Notified the R3DO (Duncan). |
| ENS 50246 | 30 June 2014 23:54:00 | This report is being made under 10CFR50.72(b)(3)(iv)(A), 'Any event or condition that results in valid actuation of any of the systems listed in paragraph (b)(3)(iv)(B) of this section' due to an auto start of 'A' and 'B' Standby Diesel Generators. At 1913 CDT, a grid disturbance during a local thunderstorm caused a valid bus undervoltage condition that resulted in the auto start of both the 'A' and 'B' Standby Diesel Generators. The 'A' and 'B' Standby Diesel Generator supply breakers did not close onto their respective buses as they remained powered by their normal power supply, the 1X003 Startup Transformer, during and after the event. NextEra Duane Arnold personnel inspections revealed no issues with breakers in the switchyard. ITC (Iowa Transmission Company) reported a fault on a 161 Kv line in the NextEra Duane Arnold vicinity. Offsite power remained operable during and following the event. As designed the 'A' and 'B' Emergency Service Water systems auto started when the diesel generators auto started. The Emergency Service Water systems and both Standby Diesel Generators have been returned to standby/readiness condition. All ECCS (Emergency Core Cooling System) systems were available before the event and have remained available following the event. The licensee notified the NRC Resident Inspector. |
| ENS 47709 | 29 February 2012 18:07:00 | On 2/29/2012 at 0905 (CST) during scheduled surveillance testing it was discovered that Secondary Containment isolation damper 1VAD017B3 would not fully isolate. 1VAD017B3 was declared inoperable per Technical Specification 3.6.4.2 Condition A and an 8 hour action statement to isolate the affected flowpath via a closed and deactivated damper was entered. While performing subsequent actions to isolate the companion isolation damper, 1VAD017A3, it was found on 2/29/2012 at 1222 (CST) that this damper also failed to fully isolate. This left both Secondary Containment isolation dampers in the same flowpath unable to isolate, and Technical Specification 3.6.4.2 Condition B was entered with a 4 hours action statement to isolate the affected flowpath. This condition is reported under 50.72(b)(3)(v)(C), any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of the structures or systems that are needed to control the release of radioactive material. Further actions to isolate the flowpath were successful and both 4 hour and 8 hour Technical Specification action statements were completed within the required time. The licensee informed the NRC Resident Inspector. |
| ENS 46619 | 17 February 2011 17:12:00 | At 1439 (CST), on 2/17/2011, the NextEra Energy Duane Arnold control room was informed that an emergency siren in the Cedar Rapids area was alarming. This information came via the Cedar Rapids Police Department and Linn County Emergency Management Agency who stated that they had been informed that a siren was alarming. No emergency condition exists at NextEra Energy Duane Arnold and efforts are currently underway to determine if in fact an emergency siren is alarming. The licensee notified the NRC Resident Inspector and the local press. |
| ENS 46104 | 17 July 2010 00:51:00 | At 2134 (CDT) on 7/16/2010 the NextEra Energy Duane Arnold control room was informed that an emergency siren in the Cedar Rapids area was alarming with an emergency message. This information came via a local news station stating that they had been receiving several phone calls regarding the siren message. No emergency condition existed at NextEra Energy Duane Arnold and the siren appears to have malfunctioned and incidentally relayed the emergency message. NextEra Energy Duane Arnold has informed local media and the Linn County Emergency Director of the malfunctioning siren, and that no emergency condition exists at NextEra Energy Duane Arnold. The single siren (of the 144 total in the local siren system) was deactivated. The licensee notified the NRC Resident Inspector. |
| ENS 45873 | 26 April 2010 05:18:00 | This report is being made under 50.72(b)(2)(iv)(B) for inserting a manual reactor scram due to rising vibrations on the #6 turbine bearing. A planned reactor shutdown was in progress with reactor power at 13.8% when turbine vibrations approached procedural limits which would require a manual scram of the reactor. The scram was uncomplicated; all control rods fully inserted. The reactor is in Mode 3, Hot Shutdown. Cooldown has been established to the condenser using main steam line drains. The NRC Resident Inspector has been informed. |
| ENS 44291 | 12 June 2008 15:19:00 | At 1130CDT on 6/12/2008, the Duane Arnold Energy Center was informed due to flooding in the local area that access to the Joint Information Center (JIC), the Offsite Radiological Analytical Laboratory (ORAL), the Offsite Relocation and Reassembly Area (ORRA), and the Emergency Operations Facility (EOF) have been lost. This constitutes a reportable condition per 10CFR50.72(b)(3)(xiii) due to the major loss of offsite response capability. The ORAL function will be maintained by the Iowa State Hygienics Lab. At the present time the remaining facilities are being relocated or moved to the Linn County Emergency Operations Center (EOC) located at the Kirkwood Community College Campus. Also, although multiple roads in the area are closed due to high water level, evacuation capability in the EPZ is being maintained. Also, at 1256CDT on 6/12/2008, Duane Arnold Energy Center was informed that local commercial phone service through the Palo phone system has been lost. This service also includes our ability to fax and access the internet. We have also lost our FTS2001 ENS connection. Again, per 10CFR50.72(b)(3)(xiii) this represents a major loss of offsite communication capability. Offsite communications is being maintained currently thorough our microwave and cell phone systems. Onsite communications are possible through our in house PBX and page system. Contingency plans are in effect to setup a mobile satellite uplink that would include voice and data capability. The NRC Resident Inspector has been informed.
At 1430CDT on 6/12/2008, Duane Arnold Energy Center lost communications capability via commercial phone line, FT2001 ENS system and the microwave phone system. This meets the threshold criteria of an EAL classification of an Unusual Event. At 1440CDT the Shift Manager declared that Unusual Event and notifications were made to Linn County Emergency Management Agency, Benton County Emergency Management Agency and the Iowa Homeland Security Emergency Management Division. Currently, offsite communication is still possible via our installed cell phone and satellite systems and onsite communications remain possible via our PBX and page system. The NRC Resident Inspector has been informed. Notified ET Member (B. Mallet), all IRD Management (B. McDermott, W. Gott, M. Leach), Commissioners' Staffs (D. Skeen, T. Hipschman, S. Baggett, J. Thoma, D. Coe), EDO Staff (J. Adams), PAO (E. Brenner), OCA (D. Decker), RDOs (R. Summers, B. Bonser, P. Louden, G. Miller), FEMA, DOE, USDA, and HHS.
On 6/12/2008 at 1444 FPLE-DAEC declared an unusual event (SU6.2) due to loss of all offsite communication. These systems included the FTS 2001, microwave phone lines, and commercial phone lines due to flooding of the Palo, Iowa phone station. Since that date FPLE-DAEC has reestablished two of the three offsite communication methods. The microwave telephone system has been restored and the commercial phone lines have been restored through a new exchange through the town of Shellsburg, Iowa, which was not affected by the flood. With these two lines of offsite communications reestablished the DAEC will de-escalate from the Unusual event from the loss of offsite communication. FPLE-Duane Arnold will be issuing a press release stating the unusual event has been cancelled. The NRC senior resident inspector has been notified and the state of Iowa, Linn County, and Benton county will be notified. The licensee exited the Unusual Event at 1428 EDT on 06/19/08. Notified R3DO (Kunowski), NRR EO (Fred Brown), IRD MOC (Bill Gott), DHS, and FEMA.
Multiple power sources are now available to the Emergency Operations Facility. The licensee notified the NRC Resident Inspector. Notified the R3DO (Kozak). |