Three Mile Island accident

(Wikipedia) - The Three Mile Island accident was the most significant accident in the history of the American commercial nuclear power generating industry.
... The accident began on Wednesday, March 28, 1979, and ultimately resulted in a partial core meltdown in Unit 2 of the nuclear power plant (a pressurized water reactor manufactured by Babcock & Wilcox) of the Three Mile Island Nuclear Generating Station in Dauphin County, Pennsylvania near Harrisburg. Continued