(FILES): This April 11, 1979 file photo

This April 11, 1979 file photo released by the US National Archives shows a view of the Three Mile Island Nuclear Power Plant near Middletown, Pennsylvania. Nearly 32 years after the March 28, 1979 accident at Three Mile Island, the Fukushima nuclear accident is considered "worse than Three Mile Island, but not as great as Chernobyl," Andre-Claude Lacoste, head of France's safety agency, said on March 14, 2011 (US National Archives/AFP/Getty Images)

This April 11, 1979 file photo released by the US National Archives shows a view of the Three Mile Island Nuclear Power Plant near Middletown, Pennsylvania. Nearly 32 years after the March 28, 1979 accident at Three Mile Island, the Fukushima nuclear accident is considered “worse than Three Mile Island, but not as great as Chernobyl,” Andre-Claude Lacoste, head of France’s safety agency, said on March 14, 2011 (US National Archives/AFP/Getty Images)