"BROWNVILLE, Neb. — Like inhabitants of a city preparing for a siege, operators of the nuclear reactor here have spent days working to defend it against the swollen Missouri River at its doorstep. On Sunday, eight days after the river rose high enough to require the operators to declare a low-level emergency, a swarm of plant officials got to show off their preparations to the chairman of the Nuclear Regulatory Commission.
The reactor, Cooper Station, is one of two nuclear plants on the Missouri River that are threatened by flooding. The second reactor, Fort Calhoun, 85 miles north, came under increased pressure for a brief period on Sunday. Before dawn, a piece of heavy equipment nicked an eight-foot-high, 2,000-foot-long temporary rubber berm, and it deflated. Water also began to approach electrical equipment, which prompted operators to cut themselves off from the grid and start up diesel generators. (It returned to grid power later Sunday.) Both nuclear plants appeared prepared to weather the flooding, their operators and federal government regulators said.
Fort Calhoun was shut down in April for refueling and stayed closed because of predictions of flooding. Plant officials say the facility is designed to remain secure at a river level of up to 1,014 feet above sea level. The water level stabilized at 1,006.5 feet on Sunday, according to the Omaha Public Power District, the operator of the Fort Calhoun plant."