Three Mile Island Nuclear Plant Back Up and Running

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Three Mile Island Nuclear Plant, Middletown, Pa.

The Nuclear Regulatory Commission has given TMI the green light to start producing energy after shutting down the plant’s Unit 1 reactor back in August. Three Mile Island officials have since discovered coolant system leaks through “micro-cracks” in the pressurizer. The pressurizer balances liquid and steam, keeping the two separate so that any radiation stays within the reactor.

NRC inspectors monitored the repair work. The plant began operating Tuesday afternoon. The Nuclear Regulatory Commission is also reviewing the plant’s flooding and seismic evaluations, following the meltdown at the Fukoshima nuclear plant in Japan last year.