Operator error blamed in A-plant mishap at TVA

An operator error was blamed Thursday for a nuclear plant accident that triggered an emergency alert and sent 100,000 gallons of radioactive water raining down on 13 unsuspecting workers. The mishap, which authorities said had a danger potentional of about "1/2 on a scale of 10," happened in the reactor room at the Tennessee Valley Authority's Sequoyah plant in East Tennessee.

TVA officials said an assistant operator accidentally opened a valve, diverting the radioactive water to a sprinker system.