And it'll be the first test for the new owner, Constellation Energy Corporation.
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In February, Exelon completed the separation of its utility businesses from its power generation division. And Constellation, based in Baltimore, became owner of 75% of the Cordova nuclear plant. MidAmerican Energy owns the other 25%.
In Illinois, Constellation now owns nuclear plants in Braidwood, Byron, Clinton, Morris, Marseilles, and Cordova.
Federal and state regulators oversee a disaster drill at the plant every other year. First responders and others will demonstrate how prepared they are to respond to an unknown threat or accident, such as a radiological leak, security breach, or severe weather.
Hundreds of Constellation employees will participate in the exercise on Tuesday.