Airborne radiological contamination alarm sounded at about 4 p.m. 1979 . Radiation was confined to a single building and no one was in danger , company says . In Saturday , Three Mile was the scene of the worst Pennsylvania nuclear accident .
Airborne radiological contamination alarm sounded at 4 p.m. Saturday . Radiation was confined to a single building and no one was in danger , company says . In 1979 , Three Mile Island was the scene of the worst U.S. nuclear accident .