A leak of ammonia water at Watts Bar Nuclear Plant in Spring City, Tenn., prompted TVA to file a notice of an unusual event Friday to the Nuclear Regulatory Commission.
TVA spokesman Travis Brickey said the leak was caused by a faulty valve and occurred in the turbine area of the electricity plant. The event did not involve nuclear areas, Brickey said.
The valve failure caused about 100 gallons of water treated with ammonia to spill from a tank onto the floor. The vapors required the evacuation of workers in that area, he said.
The workers were able to return to their stations about 1:30 p.m.
Brickey said the water is treated with ammonia to ensure it is hyperpure for use in the plant's steam generator.
He said no one was injured, and public safety was never threatened.
TVA also notified state officials, Brickey said.
NRC spokesman Joey Ledford said the notification to nuclear regulators was routine and resident NRC inspectors were at the plant, overseeing the operations there.
Ledford said he was not aware of any NRC concerns over the event that might prompt greater federal oversight.