Tens of millions of acres in the US corn belt have flooded, which will spike the cost of gas and food over the next several months. Worse, several nuclear power plants sit in the flooded plains. Both nuclear plants in Nebraska are partly submerged and the FAA has issued a no-fly order over both of them.
On June 7, the Fort Calhoun Nuclear Power Plant filed an Alert with the Nuclear Regulatory Commission after a fire broke out in the switchgear room. During the event, spent fuel pool cooling was lost when two fuel pumps failed for about 90 minutes.
On June 9, Nebraskas other plant, Cooper Nuclear Power Station near Brownville, filed a Notice of Unusual Event (NOUE), advising it is unable to discharge sludge into the Missouri River due to flooding, and therefore overtopped its sludge pond.
Other flood-related TFRs were issued on June 13 for the Garrison Dam in Bismarck, North Dakota and on June 5 for rescue operations in Sioux City, SD.
Under the four-level nuclear event scale used in the US, an NOUE is the least hazardous. In an Alert, however, events are in process or have occurred that involve an actual or potential substantial degradation in the level of safety of the plant, according to the NRC.
Despite some media reports, Ft Calhoun is not at a stage 4 level of emergency, which under the US scale, would be actual or imminent substantial core damage or melting of reactor fuel with the potential for loss of containment integrity.
If that rumor refers to the seven-level International Nuclear and Radiological Event Scale, a Level 4 incident requires at least one death, which has not occurred.
Continued flooding does threaten the plants, however. As nuclear engineer Arnie Gundersen explains in the below video, cooling pumps must operate continuously, even years after a plant is shut down.