The Fort Calhoun Nuclear Power Station is located on the west bank of the Missouri River, 20 miles north of Omaha, in Nebraska. The power plant is owned and operated by the Omaha Public Power District.
A flood assessment performed by the Nuclear Regulatory Commission in 2010 indicated that the Station “did not have adequate procedures to protect the intake structure and auxiliary building against external flooding events.”The assessment also indicated that the facility was not adequately prepared for a “worst-case” flooding scenario.
Reportedly, 9 days ago, on June 6, 2011, a Level-1 Emergency was declared at the Station because of the imminence of flooding from the Missouri River. The Missouri River is above flood stage and is expected to rise further and remain above flood stage for several weeks to a month.
A day later, on June 7, an electrical component in a switcher room in the nuclear power station caused a small fire with poisonous gases and Halon extinguisher activation, which forced a partial evacuation. The fire was no longer active when the fire brigade arrived and according to officials, the public was never in any danger, however in response, the Nuclear Regulatory Commission declared an alert, which is a level 2 incident.
On June 8, it was reported that the fire resulted in the loss of cooling for the reactor’s spent fuel pool. Any of loss of coolant in a nuclear plant risks a meltdown — a serious event because of the potential for release of radioactive material into the environment.
That day, at the Fort Calhoun plant, a pump used to recirculate coolant water through the spent fuel pool was offline for an hour. But we are told that backup equipment wasn’t needed because the pump was restored long before the estimated time to boiling temperature of 88,3 hours. [Source: Wikipedia]
Despite that, the plant’s been shut down.
Here’s Arnie Gundersen, a nuclear engineer talking about what happened at Ft. Calhoun. Gundersen is chief engineer of energy consulting company Fairewinds Associates and a former nuclear power industry executive who had served as an expert witness in the investigation of the Three Mile Island accident.
H/t beloved fellow Joseph.
For an Update of this, go here.