Algis J. Laukaitis of the Lincoln Journal Star has asked a series of questions to Nebraska's nuclear power utilities in an effort to separate fact from rumor as flood waters threaten the Fort Calhoun and Cooper atomic reactors on the severely flooded Missouri River near Omaha. Dave Lochaum of the Union of Concerned Scientists expressed concern about the risk of upstream dams bursting and sending a wall of water down the Missouri, which could inundate the riverside reactors. A burst levee near the Cooper atomic reactor -- an identical twin to the Fukushima Daiichi Units 1 to 4 -- provided a temporary reprieve to the rising waters. The floodwaters near Cooper suddenly dropped more than 1.5 feet as its waters spread out into the countryside through the breached levee. But federal authorities warn such a respite will be short-lived, as flood waters are predicted to rise again in coming days, despite the levee breach.