Pennsylvania plant was site of most serious nuclear meltdown and radiation leak in US history in 1979

A nuclear reactor at the notorious Three Mile Island site in Pennsylvania is to be activated for the first time in five years after its owners, Constellation Energy, struck a deal to provide power to Microsoft’s proliferating artificial intelligence operations.

The plant was the location of the most serious nuclear meltdown and radiation leak in US history, in March 1979 when the loss of water coolant through a faulty valve caused the Unit 2 reactor to overheat. More than four decades later, the reactor is still in a decommissioning phase.