Keizo Ishii grabs a dosimeter from a table and strides over to a lump of uprooted grass. It’s a blazing August day in Fukushima City. The professor of nuclear engineering, an with the aura of a mad scientist as sweat drips from his brow and gray hair wisps out from under his baseball cap, has come from Tohoku University in Sendai to help officials here think creatively about radioactive waste.
Ishii dangles the microphone-like extension that measures radiation over the grass. The needle edges past 4 microsieverts per hour. “Very high activity,” he pronounces. He moves the instrument sideways to the bare soil from which the grass has been peeled back. “See?” he says, watching the needle sink below 1. “See? 0.8… no! 0.6!”
Nearly five months after March 11, the physical process of cleaning up the world’s worst nuclear accident since Chernobyl has begun. Untold numbers of buildings, sidewalks, trees, gardens, parks, streets, school yards and gutters were dusted in radioactive particles after the earthquake and tsunami crippled the Fukushima Dai-ichi nuclear power plant. Though a circle within a 20-km radius of the plant and some other high-radiation spots remain evacuated, a much larger area is still home to tens of thousands of people who want those particles out of their lives as soon as possible.
The cities of Fukushima, Date and Minami-soma have announced ambitious plans to decontaminate their cities, starting with schools and other parts of town frequented by kids. More municipalities are expected to follow. Though iodine, one of the elements released after the explosions at the plant, only has a half-life of eight days and has already decayed, cesium 134 and 137 stay radioactive for 4 and 30 years, respectively. “It’s long,” says Ishii. “Fukushima cannot wait for it.”
The decontamination taking place around Fukushima City is surprisingly low tech. Armed with shovels, long-handled brushes and high-pressure water guns, some 3700 city employees and resident volunteers are scrubbing parks, roads, schools, walkways, gutters and grates. Officials are openly frustrated that this is a process they have had to initiate — and so far front the money for — on their own. “I personally feel that it’s up to the country and TEPCO to undertake this work,” says Tatsuo Miura, the head of the city’s crisis management team. “But in reality, it’s the city, the prefecture and the people who are going to have to do it.” Miura says the city has not calculated the collective cost of the project, but when they do, “We will bill it to the government.”
The central government says that it plans to set aside up to $300 million for decontaminating schools and playgrounds affected by the nuclear crisis. But Tokyo, seemingly preoccupied with what appears to be the decline of yet another prime minister, has yet to offer its help getting the job done. In Minami-soma, where decontamination will begin this month, help will be coming from experts at Tokyo University.
Nor has Tokyo offered any long-term solution for the radioactive waste that is quickly accumulating around the prefecture. In Fukushima City, officials has been disposing some waste at an industrial dumping site, but residents in the area are —understandably — unenthusiastic about that solution. As of August 1, according to the Yomiuri Shimbun, radioactive sludge from sewage and water plants was building up at that site at a rate of about 14 tons per day. The Japanese daily conducted a survey indicating that 120,000 tons of sludge is also being stored at sites in Tokyo and 13 other prefectures outside the Fukushima region. The government has said it plans to pass a law mandating how topsoil and other waste will be handled, but it is unclear when that will be passed.
As parks and school grounds are stripped of topsoil, the city is doing the only thing it can do: burying the irradiated soil on the sites where it has been removed. In a small playground behind a public housing unit in Fukushima City, several workers shovel irradiated dirt into a deep square hole that has been lined with rubber. The contaminated dirt will be covered in at least 50 centimeters of clean topsoil, according to city guidelines, a process that officials say has lowered radiation levels by 80% in schools. (An official at Minami-soma said his city would follow the same procedure.) According to measurements the city has taken, when dirt that measured 4.13 microsieverts was buried and covered, radiation levels on the surface dropped to .13.
It’s hardly a perfect solution, but officials say it’s the only one that they have for now. “We would very much like the central government to take control of [the waste],” says Miura. “It is safe,” he reiterates. “But what is safe is not necessarily what is a relief to the public.”
Ishii, the nuclear engineer, is in Fukushima to try to figure out a way that this city — and others — can minimize that waste. Cesium naturally binds with the clay contained in soil. The irradiated soil that city workers are digging up are deposited in plastic bags, and then put in tubs to be washed. The wet dirt is then put into a cement mixer, where the lighter clay rises to the surface, and the heavier soil, theoretically cesium free, sinks to the bottom. If this system works, it could reduce the amount of radioactive waste generated from soil decontamination by up to 90%.
And the other 10%? For now, it will go into dozens of blue plastic tubs sitting at the edge of the park. Those will go into storage until further notice. “We’re trying to figure out how to condense the waste soil,” Ishii says. “We haven’t figured that out yet… Maybe two years. Three years.”
— With reporting by Terrence Terashima