FULTON — A central Missouri nuclear plant evacuated for nearly an hour after flammable hydrogen gas was detected.
AmerenUE's Callaway Plant went under an unusual event declaration, the least significant emergency classification, on Thursday from 10:21 a.m. to 11:15 a.m.
AmerenUE officials said the flammable hydrogen gas was detected in the turbine building in amounts that would adversely affect plant operations.
Hydrogen is used to cool the electric generator at the plant.
AmerenUE said the building was evacuated as a precaution and the declaration was lifted when tests indicated the hydrogen level was down.
The source of the leak is under investigation after federal, state and local agencies were notified.