Five years ago today a magnitude 9.0 earthquake off the coast of northeastern Japan unleashed a powerful, 30-foot-high tsunami that swept across the landscape, killing 15,000 people, displacing nearly 400,000 others, and triggering one of the worst nuclear disasters in history — a triple meltdown at the Fukushima Daiichi nuclear power plant.
The disaster has dramatically altered Japanese society and caused nations around the world to reconsider the efficacy of nuclear power generation, particularly given the costs of cleaning up the disaster and compensating victims will likely be $100 billion — a bill that the Japanese government, not the electricity company that owned the plant, has been picking up.
James Acton, the co-director of the national nuclear program at the Carnegie Endowment for International Peace, said that when thinking about the disaster's impact on Japanese society, it's important to remember its scope and the thousands upon thousands of lives lost in the tidal wave alone.
"Just in terms of the scale of the loss, I mean it was just extraordinary," Acton said. "And that has caused a deep, deep, deep scar."
A river in Iwaki, Fukushima, is flooded with vehicles and other objects on March 11, 2011, after a 9.0-magnitude earthquake struck off the Pacific coast, triggering a 33-foot-high (10-meter) tsunami, which hit the Fukushima Daiichi nuclear power station and caused multiple meltdowns on March 12.
In Fukushima prefecture, the earthquake knocked out the external electrical supply to the nuclear power plant, and then the tsunami swamped the backup diesel generators. A black out occurred, stripping engineers of control over temperatures inside the facility's reactors — three of which ultimately melted down.
"The cleanup is going to be a multi-decades process," Acton said. Most of the work has been focused on stabilizing the situation at the plant, he said, and the three reactors that melted down are still hot. A related problem is all the radioactive water on site, a result of cooling those reactors.
"Japan has a nominal policy of completely remediating the area so that people can come back," Acton added. "I do not regard that goal as realistic."
Edwin Lyman, the coauthor of Fukushima: The Story of a Nuclear Disaster and a senior scientist at the Union of Concerned Scientists (UCS), is also concerned about the plans to move people back to the area.
"A lot of the radiation exposure as a result of the accident hasn't really occurred yet," he said. "It really will come from people who move back into contaminated areas."
Norman Kleiman, an associate research scientist at Columbia University's Mailman School of Public Health and a radiation expert, said that two of the radioactive isotopes released by the disaster, strontium and cesium, have long half-lives — about 30 years — and will remain a danger to human health for far longer.
"Most scientists believe there is no level of radioactivity which we deem safe from a cancer point of view," he said.
However, if there is an uptick in cancer rates in the region, with leukemia being the most likely, it would be a very small one, Kleiman said. The mental health effects of the disaster and evacuation — like post-traumatic stress disorder, depression, anxiety — are "by far" the bigger health concerns, he said.
Tatsu Suzuki, director the of Research Center for Nuclear Weapons Abolition at Nagasaki University, said the costs of decommissioning the reactors, decontaminating the area, and compensating victims is about 110 billion yen, or nearly $100 billion dollars.
"Officially speaking, all the bills should be paid by TEPCO eventually," Suzuki said, referring to the company, now half-owned by the Japanese government, that operated the plant. TEPCO has paid about 20 percent of those costs, he said. "Basically, the Japanese citizens are paying for it."
The effects of Fukushima reverberated globally, said Nathan Hultman, director of the Center for Global Sustainability at the University of Maryland's School of Public Policy.
"Fukushima — I think around the world — caused governments and individuals, and energy consumers, and people living alongside nuclear [facilities], to ask about safety," Hultman said. "And it really did call the question of how deeply do we want to be investing in this particular technology."
Related: The Soviet Union Dumped a Bunch of Nuclear Submarines, Reactors, and Containers into the Ocean
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