Missouri nuclear plant shut down for third time in nine months

JEFFERSON CITY, Mo. -- Ameren Corp.'s nuclear plant in mid-Missouri has halted operations because of a non-nuclear issue involving the generator, the utility company said.

The shutdown announced Thursday was the third time in nine months the plant about 30 miles north of Jefferson City has halted operations, The St. Louis Post-Dispatch reported.

The latest shutdown occurred when the plant was ramping up after maintenance, Ameren said. The utility did not indicate when the plant would begin operating again.

Operations at the plant first stopped in April, when a main feedwater valve malfunctioned. The second shutdown happened in September after a piece of ductwork became detached and caused a generator to trip.

Edwin Lyman, director of nuclear power safety for the Union of Concerned Scientists, said it is unusual for a nuclear plant to have three "scrams" -- sudden, unplanned shutdowns -- in one year. Most plants average one scram every two years, he said.

Ameren also announced Thursday that it had acquired a wind farm in northwest Missouri that will eventually generate 300 megawatts. Ameren acquired its first wind farm in late December near Kirksville, with a capacity of 400 megawatts.