Five years ago this month a devastating tsunami engulfed Japan's northeastern coast, triggering the worst nuclear disaster since Chernobyl. Washing over a 10-meter-high seawall, the waves knocked out electricity at Fukushima Daiichi nuclear power plant, causing cooling systems to fail and half of the facility's uranium cores to overheat and melt through their steel containers. Hydrogen explosions in the next few days damaged three of the reactor buildings, venting radioactive materials into the air. That plume of airborne contamination forced some 160,000 people to evacuate from their homes.
Today the disaster site remains in crisis mode. Former residents will not likely return anytime soon, because levels of radioactivity near their abodes remain high. Even more troublesome, the plant has yet to stop producing dangerous nuclear waste: its operator, the Tokyo Electric Power Company (TEPCO), currently circulates water through the three melted units to keep them cool—generating a relentless supply of radioactive water. To make matters worse, groundwater flowing from a hill behind the crippled plant now mingles with radioactive materials before heading into the sea.
TEPCO collects the contaminated water and stores it all in massive tanks at the rate of up to 400 metric tons a day. Lately the water has been processed to reduce the concentration of radionuclides, but it still retains high concentrations of tritium, a radioactive isotope of hydrogen. Disputes over its final resting place remain unresolved. The same goes for the millions of bags of contaminated topsoil and other solid waste from the disaster, as well as the uranium fuel itself. Health reports, too, are worrisome. Scientists have seen an increase in thyroid cancers among the children who had lived in Fukushima at the time, although it is too early to tell if those cases can be attributed to the accident.
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Nevertheless, Japan's government plans to recommit to nuclear power. Prime Minister Shinzo Abe recently emphasized the urgent need to restart the country's nuclear power plants, which all were taken offline following the Fukushima Daiichi disaster. So far two have been brought back to full operation.
SOURCES: “THE WORLD NUCLEAR INDUSTRY STATUS REPORT 2015,” BY MYCLE SCHNEIDER AND ANTONY FROGGATT; JULY 2015 (first four items); “ACCOUNTING FOR LONG-TERM DOSES IN ‘WORLDWIDE HEALTH EFFECTS OF THE FUKUSHIMA DAIICHI NUCLEAR ACCIDENT,’” BY JAN BEYEA ET AL., IN ENERGY & ENVIRONMENTAL SCIENCE, VOL. 6, No. 3; March 1, 2013 (last item)