The hydrogen explosions at the three Fukushima Daiichi nuclear power plants in March 2011 launched one of the largest disasters in industrial history. A year after the Japanese government declared that the reactors were under control, experts continued to find radioactive leaks. According to TEPCO's latest estimate, cleaning up the mess—removing fuel rods and debris, decommissioning the reactors, and decontaminating some of the surroundings—will take four decades and cost at least $125 billion.” Along the way, thousands of workers will be exposed annually to levels of radiation well in excess of 20 milliSieverts, the internationally recognized maximum limit for normal working conditions.