Three Mile Island

Three Mile Island, site in the Susquehanna River, near Middletown, Penn., of a nuclear reactor that, on March 28, 1979, began to emit “puffs” of radiation as a result of malfunction of the cooling system, aggravated by problems with the computer monitors and some human error. Initial reports downplayed the crisis, but it developed that a core meltdown was a possibility and that a large, potentially explosive hydrogen bubble had formed in the reactor; also, it was learned that no workable plans existed for evacuating the area. Luckily, catastrophe was averted without fatalities or known injury.

See also: Nuclear reactor.