TAMURA, FUKUSHIMA, Japan — One bamboo branch and spade of soil at a time, workers are slowly purging Fukushima of its nuclear legacy.

On a chilly, overcast afternoon in Tamura, which lies along the 20-kilometer (12 mile) evacuation zone around the stricken Fukushima Daiichi nuclear power plant, crews continue the painstaking task of decontaminating neighborhoods irradiated by the March 2011 triple meltdown.

Some tear down bamboo groves near homes belonging to evacuated families. Others drill into layers of winter-hardened earth, and shovel it into black hazardous waste sacks.

When radiation levels fall to their target level, they will add a new layer of clean topsoil sourced from elsewhere.

But two years after the earthquake and tsunami, which killed around 19,000 people along Japan’s northeast coast and sparked the world’s worst nuclear crisis in a quarter of a century, the multibillion-dollar decontamination drive, involving thousands of workers, is making slow progress.

The biggest radiological cleanup the world has ever seen has been hampered by violations of employment laws, shoddy working practices and a shortage of people willing to work in an irradiated environment. The failure, so far, to secure permanent storage sites for contaminated waste has added to the authorities’ woes.

Radiation levels vary around evacuated towns and villages earmarked for decontamination. At this spot in the Miyakoji district of Tamura, the reading at ground level is more than three times the target set by the government, but much lower than the dose above which people are believed prone to damage to their long-term health through thyroid cancer, leukemia and other cancers.

Environmental hazards aside, the thousands of casual laborers who have answered the cleanup call must perform grueling work: clearing grass, leaves and branches, drilling concrete, shoveling soil and hosing down the walls and roofs of homes abandoned in the immediate aftermath of the disaster.

Just months after it began, the decontamination drive is the subject of widespread malpractice allegations. Contractors have been accused of withholding additional dangerous work payments, and of sending workers into radiation zones with minimal training and only basic equipment.

A grim pursuit

The cleanup covers only part of the area irradiated by Fukushima Daiichi’s nuclear fallout. Neighborhoods where the readings exceed 50 millisieverts a year are regarded as too contaminated to consider an early return for residents; people from villages closest to the nuclear plant may have to wait decades before they can go back. Some accept that they never will.

Fukushima’s topography has only complicated the task. About 70 percent of the prefecture is covered in mountainous forests, where cesium-137, which has a half-life of 30 years, and other radioactive isotopes have found their way into trees and soil. For now, they will be left as they are, a natural testament to a manmade disaster.

Instead, the focus of the cleanup is on 90,000 homes and dozens of schools in 11 towns and villages where some or all of the residents were forced to flee.

The radiation at ground level at the Miyakoji site visited by GlobalPost is around is 0.7 microsieverts an hour. By the time their work is done, the crew hopes to have brought that down to the government-set target of 0.23 microsieverts an hour at ground level.

“The worst part about this job is that the radiation levels just won’t go down,” said Shigeru Watanabe, a decontamination worker. “Sometimes we have to dig 5 cm [2 inches], sometimes 10 cm. We have to get the readings down to 0.23 microsieverts per hour … but achieving that will be really tough.

“All of the residents around here are having a hard time. They’ve been evacuated and are living in temporary housing, so I thought I should do as much as I can to help things get back to normal as quickly as possible.”

“There are no children around here because everyone was evacuated. It would be great to see them return soon.”

Another worker, Yuji Mizuno, was transferred to this site, located about 15.5 miles from the Fukushima Daiichi plant, by his company just over a month ago. “As long as I am in the 20 km-30 km range [from the nuclear power plant], I’m not at all worried about my health,” he said.

All of the workers in Miyakoji we spoke to said they had been properly trained and equipped, and that they were treated well. The local farming machinery firm in charge of the work granted GlobalPost access to two decontamination sites, and permitted us to conduct unsupervised interviews with employees.

But their counterparts at other sites around Fukushima claim that contractors have cheated them out of special payments and withheld information on their radiation exposure.

In addition, some contractors allegedly ordered their employees to dump contaminated soil, plants and water into rivers rather than collect them for storage and eventual disposal. The Environment Ministry promised to investigate the claims, after the Asahi Shimbun, a newspaper, filmed laborers performing slipshod work.

In a meeting with reporters earlier this month, three workers, who asked not be identified by the media, admitted they had dumped leaves and branches into rivers. “I wondered if it was really all right to do that,” one said. “But I was afraid that I might be fired if I refused. And my supervisor was doing the same thing right in front of me.”

The ministry said it would write to contractors reminding them to follow government-set decontamination guidelines.

In other cases, workers have been denied special allowances for working inside the 20 km (12.4 mile) evacuation zone.

One laborer who asked to be identified only by his last name, Nakamura, said he had spent about 50 days working just inside the no-go zone on a short-term contract for a major construction company.

GlobalPost in-depth: After the tsunami

On top of his daily wage of 12,000 yen ($125), he was entitled to 10,000 yen a day from the central government as danger pay for operating in a highly radioactive area. He says the government paid the money — more than half a million yen in total — but that his employer had simply held on to it.

The 54-year-old, who with several coworkers has formed a union to demand payment, believes that thousands may have been swindled out of cash.

“We’re trying our best, but we’re just a minnow up against a powerful corporation,” Nakamura, who has since quit his job, told GlobalPost.

The Environment Ministry stopped short of taking legal action or naming the companies concerned, saying only that it would investigate the claims and send written demands that workers be paid retrospectively.

Nakamura also worries about radiation. He underwent a check using a full body counter at the start of his two-month contract, and then again when it ended. But the company has yet to tell him his readings, despite repeated requests. When he left, the dosimeter Nakamura had worn around his neck to measure cumulative external exposure was taken away. He still doesn’t know the readings stored inside the device.

“If I become ill at some point, I’ll have no evidence of my cumulative radiation dose to offer as proof that I worked in a dangerous environment,” he said.

Nakamura said he and the other members of his crew — protected only by thick surgical masks, regular overalls and gloves — worked long days collecting leaves and feeding them into a huge cutting machine. Radiation levels near the machine were almost four times higher than the 0.23 microsievert an hour target the government has set for members of the public.

“Some of the men I worked with spent the entire day in that part of the site,” he said. “I’m at the age where I don’t need to worry too much about what might happen to my health 20 or 30 years down the line … it’s the younger guys I worry about.”

Another concern is that organized crime is trying to profit by exploiting workers in the Fukushima exclusion zone. The government’s dependence on big contractors has opened the door to the yakuza, Japan’s powerful crime syndicates, whose ties to the construction industry stretch back decades.

In January, police arrested a senior member of the country’s second-biggest yakuza group, the Sumiyoshi-kai, for providing three contract employees to a construction firm involved in decontamination work in Fukushima, and pocketing a third of their wages.

Media reports said the gangster had decided to infiltrate the cleanup because it offers higher financial rewards than regular building work. The contract to clean up Tamura, for example, is worth 3.3 billion yen.

Although only one arrest has been made, anecdotal evidence from Nakamura and other workers point to a much deeper underworld involvement in the Fukushima cleanup.

An investigation by the Health and Welfare Ministry also revealed widespread violations of health and safety laws, with workers being sent into hazardous areas with insufficient training or protective gear. About half of the 242 contractors involved were reprimanded, but no legal action was taken — a move that would have delayed work that is already well behind schedule.

Nakamura isn’t surprised by the lack of action against unscrupulous employers. “This whole decontamination project is not about improving the lives of ordinary people,” he said. “It’s all about profits for the big contractors. Lots of taxpayers’ money is going into their pockets, and nothing is being done about it.

“This is a Japan problem. Here, the people who work the hardest end up with the least.”

Ghost towns

Koji Sakuma, who leads a small crew of cleanup workers in Miyakoji, said here, as in dozens of other places across Fukushima prefecture, the disaster had torn families and communities apart.

Of the district’s 3,000 residents, fewer than 500 remain, many of them elderly people who are at less risk of developing radiation-related cancers in the future. Children’s voices have not been heard here for two years.

“People in their 50s and 60s who have work to do are living here, but their children and other young people are in temporary housing in places like [nearby] Koriyama and Funehiki,” Sakuma said. “About 80 percent of the local population is leading that kind of life.”

For Nakamura, the work held the double attraction of a slightly higher daily wage than he had been paid at his call-center job in Tokyo, and the chance to play a part in the revival of Fukushima, the place of his birth.

But is his and other workers’ desire to make communities near the plant inhabitable misplaced?

Attempting to keep radiation levels down in residential areas could prove futile, according to Ian Fairlie, a London-based independent consultant on radioactivity in the environment. Fairlie, who had just returned from a conference on the Fukushima crisis in New York, said there was evidence that some areas recorded the same levels of radioactive cesium-137 just 24 hours after they had supposedly been contaminated.

“This was found too after Chernobyl, where cleanups were largely ineffectual,” he said. “[Decontamination] is good for reassurance and official statements, but poor for actual dose reduction. I think the 20 km zone and other areas will have to remain permanently evacuated. That will be awful for the [tens of thousands of people] affected, but I can't really see any other way.”

Other experts agree that the work has so far been less successful than anticipated, but are more optimistic about the safety of these areas.

Last year the Japan Atomic Energy Agency (JAEA), which conducts research into nuclear energy, completed pilot cleanups in Fukushima and passed its findings on the science, logistics and cost of the operation to the Environment Ministry.

“It’s clear that [ministry] officials are finding this much harder than they expected,” said Shinichi Nakayama, deputy director of the JAEA’s Fukushima Environmental Safety Center. “No one has experience of undertaking a cleanup of this size. It isn’t something you can do by following a manual. It’s a massive technical challenge.”

While Fukushima’s highly contaminated forests will remain off-limits for some time — cutting down trees and removing soil could cause dangerous landslides — Nakayama said follow-up monitoring of areas decontaminated during the JAEA’s pilot scheme showed that none had experienced a rise in radiation after remediation work.

Aside from securing enough workers, the biggest obstacle to progress is finding plots to store waste before it is finally disposed of. There’s an urgent need, Nakayama said, to centralize waste conditioning, and establish interim storage sites and disposal facilities.

According to one estimate, the Fukushima decontamination project will produce at least 30 million cubic meters of waste — enough to fill the 55,000-seat Tokyo Dome stadium more than 20 times.

Questions are also being raised about the government-set radiation target. Currently, evacuees are being advised to wait until radiation at ground level has been lowered to 0.23 microsieverts an hour. That translates to one millisievert a year — assuming that people spend about half their time indoors — on top of normal background dose, and is the maximum limit for the public set by the International Commission on Radiological Protection. By contrast, natural background radiation around the world is around 2.4 millisieverts a year. The acceptable dose for Japanese nuclear plant workers is 100 millisieverts over five years.

Cumulative exposure to 100 millisieverts raises the risk of death from cancer by 0.5 percent over an individual’s lifetime, according to the government-affiliated National Institute of Radiological Sciences (NIRS) in Tokyo. This means that for every 10,000 people, an additional 50 will die from the disease, above the approximately 2,000 who would die from the disease normally.

In a recent report, the World Health Organization estimated that residents in the most affected areas of Fukushima Prefecture received doses ranging from 12 to 25 millisieverts in the first 12 months after the disaster.

Radiation experts disagree over the possible health consequences when the cumulative dose is lower than 100 millisieverts. “We are not yet clear if there is a higher cancer risk,” said Kazuo Sakai, director of the research center for radiation protection at NIRS. “It is said that health effects are only evident when exposure is over 100 millisieverts, but based on the cumulative doses they received, people in Fukushima did not get enough radiation to threaten their health.”

Japan’s previous government, led by the Democratic Party of Japan, set an initial safe target of 20 millisieverts a year by 2014, with one millisievert a year its long-term objective. But it is the latter, much lower level that has become the accepted benchmark among Fukushima residents.

“The one millisievert a year limit for the general public … is a very conservative figure,” Sakai said. “People are treating the one millisievert a year limit with too much caution. They think that if they go over that then they are in trouble, as if it’s the dividing line between safety and danger.”

Nakayama, who has been working on the environmental remediation of Fukushima since the nuclear accident, agrees that the one-millisievert target was overly cautious. “But now that it’s been established as the target, it would be impossible to tell residents in Fukushima to accept even a slightly higher level of exposure.”

The scientific debate means little to the workers on the ground, who have taken center stage in the Fukushima saga since the plant’s three most badly damaged reactors were brought to a stable state known as “cold shutdown” more than a year ago.

The financial cost of the cleanup continues to rise. The operator of the nuclear plant, Tokyo Electric Power (TEPCO), recently doubled its estimate of the cost of decontaminating neighborhoods and compensating victims to 10 trillion yen ($105 billion). But according to the Japan Center for Economic Research, a non-profit, independent think tank, the cost of decontaminating Fukushima prefecture’s residential districts alone could soar to an estimated $600 billion.

While the authorities ponder the financial costs, tens of thousands of black oil-based sacks filled with contaminated dirt, grass and rubble lie scattered in fields and on roadsides across Fukushima, sometimes just yards from schools and homes. It will not be moved until the government secures permanent storage sites in the face of opposition from communities that object to having tons of radioactive waste dumped on their doorsteps.

The government had set a completion date of March next year, but the slow pace of the cleanup means meeting that deadline will be next to impossible. Those among the 160,000 nuclear evacuees hoping to return home can do nothing except wait.