Eight years after triple nuclear meltdown, Fukushima No. 1’s water woes show no signs of ebbing — The Japan Times

Nearly a thousand storage tanks are scattered across the Fukushima No. 1 nuclear power plant, holding a staggering 1.1 million tons of treated water used to keep its melted reactor cores cool while they rust in the sun.

Plant manager Tokyo Electric Power Company Holdings Inc., or Tepco, plans to build more of the gigantic tanks to hold another 0.27 million tons, which is roughly the equivalent of 108 Olympic-size swimming pools. The new tanks are expected reach full capacity in four or five years.

Each tank takes seven to 10 days to fill and holds between 1,000 to 1,200 tons of liquid, Tepco officials told reporters during a tour in February organized by the Japan National Press Club. It’s been eight years since Fukushima No. 1 suffered three core meltdowns triggered by tsunami following the Great East Japan Earthquake, but the situation with the tanks may be a sign Tepco has yet to get the facility under control.

“Space isn’t a big issue at this point in time, but five or 10 years from now, after we’ve started removing the melted fuel debris, we’re going to need facilities to store and preserve it,” Akira Ono, president of Fukushima No. 1 Decontamination and Decommissioning Engineering Co., a Tepco unit overseeing the decommissioning process, said at a news conference in January.

The water issue is eating up both space and resources, but a solution is unlikely to emerge anytime soon. ”

by Ryusei Takahashi, The Japan Times

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Eight years on, water woes threaten Fukushima cleanup — Reuters

” OKUMA, Japan (Reuters) – Eight years after the Fukushima nuclear crisis, a fresh obstacle threatens to undermine the massive clean-up: 1 million tons of contaminated water must be stored, possibly for years, at the power plant.

Last year, Tokyo Electric Power Co said a system meant to purify contaminated water had failed to remove dangerous radioactive contaminants.

That means most of that water – stored in 1,000 tanks around the plant – will need to be reprocessed before it is released into the ocean, the most likely scenario for disposal.

Reprocessing could take nearly two years and divert personnel and energy from dismantling the tsunami-wrecked reactors, a project that will take up to 40 years.

It is unclear how much that would delay decommissioning. But any delay could be pricey; the government estimated in 2016 that the total cost of plant dismantling, decontamination of affected areas, and compensation, would amount to 21.5 trillion yen ($192.5 billion), roughly 20 percent of the country’s annual budget.

Tepco is already running out of space to store treated water. And should another big quake strike, experts say tanks could crack, unleashing tainted liquid and washing highly radioactive debris into the ocean.

Fishermen struggling to win back the confidence of consumers are vehemently opposed to releasing reprocessed water – deemed largely harmless by Japan’s nuclear watchdog, the Nuclear Regulation Authority (NRA) – into the ocean.

“That would destroy what we’ve been building over the past eight years,” said Tetsu Nozaki, head of the Fukushima Prefectural Federation of Fisheries Co-operative Associations. Last year’s catch was just 15 percent of pre-crisis levels, partly because of consumer reluctance to eat fish caught off Fukushima.

SLOW PROGRESS

On a visit to the wrecked Fukushima Dai-ichi plant last month, huge cranes hovered over the four reactor buildings that hug the coast. Workers could be seen atop the No. 3 building getting equipment ready to lift spent fuel rods out of a storage pool, a process that could start next month.

In most areas around the plant, workers no longer need to wear face masks and full body suits to protect against radiation. Only the reactor buildings or other restricted areas require special equipment.

Fanning out across the plant’s property are enough tanks to fill 400 Olympic-sized swimming pools. Machines called Advanced Liquid Processing Systems, or ALPS, had treated the water inside them.

Tepco said the equipment could remove all radionuclides except tritium, a relatively harmless hydrogen isotope that is hard to separate from water. Tritium-laced water is released into the environment at nuclear sites around the world.

But after newspaper reports last year questioned the effectiveness of ALPS-processed water, Tepco acknowledged that strontium-90 and other radioactive elements remained in many of the tanks.

Tepco said the problems occurred because absorbent materials in the equipment had not been changed frequently enough.

The utility has promised to re-purify the water if the government decides that releasing it into the ocean is the best solution. It is the cheapest of five options a government task force considered in 2016; others included evaporation and burial.

Tepco and the government are now waiting for another panel of experts to issue recommendations. The head of the panel declined an interview request. No deadline has been set.

NRA chief Toyoshi Fuketa believes ocean release after dilution is the only feasible way to handle the water problem. He has warned that postponing the decision indefinitely could derail the decommissioning project.

STORING INDEFINITELY

Another option is to store the water for decades in enormous tanks normally used for crude oil. The tanks have been tested for durability, said Yasuro Kawai, a plant engineer and a member of Citizens’ Commission on Nuclear Energy, a group advocating abandoning nuclear energy.

Each tank holds 100,000 tons, so 10 such tanks could store the roughly 1 million tons of water processed by ALPS so far, he said.

The commission proposes holding the tritium-laced water, which has a half life of 12.3 years, in tanks for 123 years. After that, it will be one thousandth as radioactive as it was when it went into storage.

Although experts caution that tanks would be vulnerable to major quakes, Japan’s trade and industry minister, Hiroshige Seko, said the committee would consider them anyway.

“Long-term storage … has an upside as radiation levels come down while it is in storage. But there is a risk of leakage,” Seko told Reuters. “It is difficult to hold the water indefinitely, so the panel will also look into how it should be disposed of eventually.”

Space is also a problem, said Akira Ono, Tepco’s chief decommissioning officer. By 2020, the utility will expand tank storage capacity by 10 percent to 1.37 million tons, and about 95 percent of total capacity will probably be used by the end of that year, he said.

“Tanks are now being built on flat, elevated spots in stable locations,” Ono said. But such ideal space is getting scarce, he added.

Many local residents hope Tepco will just keep storing the water. If it does get released into the ocean, “everyone would sink into depression,” said fishing trawler captain Koichi Matsumoto.

Fukushima was once popular with surfers. But young people in the area do not go surfing any more because they’ve been repeatedly warned about suspected radioactivity in the water, said surf shop owner Yuichiro Kobayashi.

Releasing treated water from the plant “could end up chasing the next generation of children away from the sea as well,” he said.

Ono says dealing with contaminated water is one of many complex issues involved in decommissioning.

A year ago, when he took over leading the effort, it felt like the project had just “entered the trailhead,” he said. “Now, it feels like we’re really starting to climb.” ”

Reporting by Kiyoshi Takenaka; Editing by Malcolm Foster and Gerry Doyle, Reuters

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Five years after the meltdown, is it safe to live near Fukushima? — Science

” A  long, grinding struggle back to normal is underway at the Fukushima Daiichi Nuclear Power Plant in Japan. As workers make progress in cleaning up contaminated land surrounding its infamous reactor, evacuees are grappling with whether to return to homes sealed off since the accident there 5 years ago. The power plant itself remains a dangerous disaster zone, with workers just beginning the complex, risky job of locating the melted fuel and figuring out how to remove it.

The magnitude 9.0 earthquake that struck northeastern Japan on 11 March 2011 and the 40-meter tsunami that followed left 15,893 dead and 2572 missing, destroyed 127,290 buildings, and damaged more than a million more. It also triggered the meltdowns at Fukushima and the evacuation of 150,000 people from within 20 kilometers of the nuclear plant as well as from areas beyond that were hard hit by fallout.

Now, the nuclear refugees face a dilemma: How much radiation in their former homes is safe? In a herculean effort, authorities have so far scooped up some 9 million cubic meters of contaminated soil and leaves and washed down buildings and roadways with the goal of reducing outdoor radiation exposure to 0.23 microsieverts per hour. Last September, the government began lifting evacuation orders for the seven municipalities wholly or partly within 20 kilometers of the plant. As the work progresses, authorities expect that 70% of the evacuees will be allowed to return home by spring 2017.

But evacuees are torn over safety and compensation issues. Many claim they are being compelled to go home, even though radiation exposure levels, they feel, are still too high. “There has been no education regarding radiation,” says Katsunobu Sakurai, the mayor of Minamisoma, where 14,000 people were evacuated after the accident. “It’s difficult for many people to make the decision to return without knowing what these radiation levels mean and what is safe,” he says. Some citizen groups are suing the national government and Tokyo Electric Power Company (TEPCO), the Fukushima plant’s owner, over plans to end compensation payments for those who choose not to return home. Highly contaminated areas close to the nuclear plant will remain off limits indefinitely.

Conditions at the plant are “really stable,” the plant manager, Akira Ono, recently told reporters. Radioactivity and heat from the nuclear fuel have fallen substantially in the past 5 years, he says. But cleanup is off to a slow start, hampered by sketchy knowledge of where the nuclear fuel is located. Last year managers agreed to a road map for decommissioning the site over the next 30 to 40 years that calls for removing melted nuclear fuel masses and demolishing the plant’s four reactor halls at a cost that could top $9 billion. TEPCO intends to start removing nuclear debris from the reactors in 2021.

Ono puts the decommissioning at “around 10%” complete. One big hurdle was cleared in December 2014, when crews removed the last of 1535 fuel rods stored in the Unit 4 spent fuel pool. At the time of the accident, some feared that cooling water had drained out of the pool and exposed the fuel to air, which might have led to overheating and melting. It hadn’t, but the fuel remained a threat.

The biggest challenge at present, Ono says, is contaminated water. Cooling water is continuously poured over the melted cores of units 1, 2, and 3 to keep the fuel from overheating and melting again. The water drains into building basements, where it mixes with groundwater. To reduce the amount of contaminated water seeping into the ocean, TEPCO collects and stores it in 10-meter-tall steel tanks. They now fill nearly every corner of the grounds, holding some 750,000 tons of water. The government is evaluating experimental techniques for cleansing the water of a key radioisotope, tritium. Ono says a solution is sorely needed before the plant runs out of room for more tanks.

TEPCO has found ways to divert groundwater from the site, cutting infiltration to about 150 tons per day. Now it’s about to freeze out the rest. Borrowing a technique for making temporary subsurface barriers during tunnel construction, a contractor has driven 1500 pipes 30 meters down to bedrock, creating something akin to an underground picket fence encircling the four crippled reactor units. Brine chilled to –30°C circulating in the pipes will freeze the soil between the pipes; the frozen wall should keep groundwater out and contaminated water in. TEPCO was planning to start the operation shortly after Science went to press.

The most daunting task is recovering the fuel debris. TEPCO modeling and analyses suggest that most, if not all, of the fuel in the Unit 1 reactor melted, burned through the reactor pressure vessel, dropped to the bottom of the containment vessel, and perhaps ate into the concrete base. Units 2 and 3 suffered partial meltdowns, and some fuel may remain in the cores.

To try to confirm the location and condition of the melted fuel, the International Research Institute for Nuclear Decommissioning, set up by TEPCO and other entities, has been probing the reactors’ innards with muons. Wispy cousins of the electron, muons are generated by the trillions each minute when cosmic rays slam into the upper atmosphere. A few muons are absorbed or scattered, at a rate that depends on a material’s density. Because uranium is denser than steel or concrete, muon imaging can potentially locate the fuel debris.

In February 2015, a group at Japan’s High Energy Accelerator Research Organization in Tsukuba supplied two van-sized muon detectors, which TEPCO placed adjacent to the Unit 1 reactor at ground level. After a month of collecting muons, the detectors confirmed there was no fuel left in the core. Because they were positioned at ground level, the devices could not image the reactor building basements and so could not pin down where the fuel is or its condition. TEPCO plans to use robots to map the location of the fuel debris so it can develop a strategy for removing it (see story, right).

A second team has developed detectors that observe muons before and after they pass through an object of interest, promising a more precise picture of reactor interiors. For Fukushima, the researchers—from Los Alamos National Laboratory in New Mexico and Japan’s Toshiba Corp.—built mammoth detectors, 7 meters across, which they intended to place outside Unit 2. That work has been postponed because TEPCO decided to first send a robot into the containment vessel; high radiation levels have delayed that plan. “Our current task is to reduce that exposure,” Ono says, using robotic floor and wall scrubbers in the area workers need to access to deploy the robot.

While the authorities struggle to clean up the site and resettle residents, some locals are judging safety for themselves. In 2014, a group of enterprising high school students in Fukushima city, outside the evacuation zone, launched an international radiation-dosimetry project. Some 216 students and teachers at six schools in Fukushima Prefecture, six elsewhere in Japan, four in France, eight in Poland, and two in Belarus wore dosimeters for 2 weeks while keeping detailed diaries of their whereabouts and activities. “I wanted to know how high my exposure dose was and I wanted to compare that dose with people living in other places,” explains Haruka Onodera, a member of Fukushima High School’s Super Science Club, which conceived the project. The students published their findings last November in the Journal of Radiological Protection. Their conclusion: “High school students in Fukushima [Prefecture] do not suffer from significantly higher levels of radiation” than those living elsewhere, Onodera says.

That’s good news for Fukushima city residents, perhaps, but cold comfort to displaced people now weighing the prospect of moving back to homes closer to the shattered nuclear plant. ”

by Dennis Normile

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Problems keep piling up in Fukushima — Voice of America

Experts say Japan’s nuclear energy problems are worsening, five years after a massive earthquake unleashed a tsunami that melted down the island nation’s nuclear reactors.

Nine million cubic meters of radioactive waste, much of it soil, are stored unsheltered in black bags throughout Fukushima prefecture, preventing tens of thousands of residents from returning home.

And the problem is going to worsen before it improves.

An estimated 13 million cubic meters of toxic soil is yet to be collected and technicians have yet to solve the contamination issue inside the Fukushima-1 Nuclear Power Plant. Government and industry officials acknowledge cleaning everything up — including decommissioning the crippled reactors — will take at least another 40 years and cost as much as $250 billion.

And that timeline and the costs – considered overly optimistic by some industry experts – are based on nothing major going wrong.

If another major earthquake hits and results in a tsunami, there will be major setbacks, admits the nuclear plant’s manager, Akira Ono.

Thousands of workers are dedicated to keeping under control the plant’s six reactors, four of which either melted down or were severely damaged.

Japan has never decommissioned a nuclear reactor, much less reactors as damaged as those at Fukushima.

It has resisted offers from foreign companies to help formulate an adequate cleanup plan.

“Unfortunately the cleanup effort continues to suffer from an inability to face the long-term decisions that have to be made in order to develop and implement an efficient plan,” said former U.S. diplomat Kevin Maher, who was running the State Department’s Japan desk when the earthquake struck.

The cleanup plan, he argues, should be driven by where to ultimately dispose the contaminated debris, fuel and water.

“Instead, Tokyo Electric Power Company (TEPCO) continues to delay those decision[s], so we see the continual buildup of more stored water, because TEPCO can’t decide what to do with it. An experienced program management company could make those decisions,” said Maher, a senior advisor at NMV Consulting in Washington.

Even if Fukushima residents with homes inside the exclusion zone are allowed to return, the thousands of bags of radioactive soil in the prefecture may give them pause.

“There is still lingering fear about radiation among the younger people who left the city,” according to Katsunobu Sakurai, mayor of Minamisoma, which had a population of 71,000 when the disaster struck.

About 57,000 people have returned to Sakurai’s city, but few of the children or those of working age have come back. (More than 1,000 of Minamisoma’s residents perished in the earthquake and tsunami, as well as deaths attributed to the chaos of the mandatory evacuation.)

The mayor notes that in adjacent villages encompassing 76,000 people, only about 5,000 residents have returned because of concerns about the radiation levels, which Sakurai said widely vary.

The black bags of radioactive soil – now scattered at 115,000 locations across in Fukushima – are eventually to be moved to yet-to-be built interim facilities, encompassing 16 square kilometers, in two towns close to the crippled nuclear power plant.

Authorities say the temporary storage sites are to hold the contaminated material for no more than 30 years before it is processed in a different prefecture, which has yet-to-be-named.

But issues with owners who do not want to sell their properties, or with clearing titles for other land needed to build the temporary sites likely mean it will take many years for all those hurdles to be cleared, according to observers.

The question of whether Fukushima can ever be adequately decontaminated is also an open one.

Japan’s environment minister has had to walk back remarks she made about the government’s decontamination target.

Tamayo Marukawa last Friday apologized for saying the government aimed to reduce the radiation level near the Fukushima-1 plant to an annual dose of one millisievert or less, a goal that has no scientific basis. (The average yearly human dose globally from naturally occurring sources is about three times that amount, according to scientists.)

The decontamination goal was set by the previous government, led by the Democratic Party of Japan, as requested by the Fukushima prefectural government.

Minamisoma Mayor Sakurai, speaking Wednesday in Tokyo at the Foreign Correspondents’ Club of Japan, chastised the administration of Prime Minister Shinzo Abe for getting its priorities wrong since the 2011 disaster.

“Economy, economy, economy,” the mayor asserted, is the central government’s mantra. But for the politicians in the beleaguered Fukushima communities in the midst of an unprecedented nuclear decontamination project and focused on recovery and rebuilding, Sakurai said “we are holding the lives of the citizens in our hands.”

More than 18,000 are confirmed to have died or still listed as missing from the 2011 quake and subsequent tsunami. ”

by Steve Herman

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How is Fukushima’s cleanup going five years after its meltdown? Not so well. — The Washington Post; Fukushima cleanup may take up to 40 years, plant’s operator says — CNN

Seen from the road below, the Fukushima Daiichi nuclear power station looks much as it may have right after the catastrophic earthquake and tsunami that caused a triple meltdown here almost five years ago.

The No. 3 reactor building, which exploded in a hydrogen fireball during the disaster, remains a tangle of broken concrete and twisted metal. A smashed crane sits exactly where it was on March 11, 2011. To the side of the reactor units, a building that once housed boilers stands open to the shore, its rusted, warped tanks exposed.

The scene is a testament to the chaos that was unleashed when the tsunami engulfed these buildings, triggering the world’s worst nuclear disaster since the one at Chernobyl, in Ukraine, in 1986. Almost 16,000 people were killed along Japan’s northeastern coast in the tsunami, and 160,000 more lost their homes and livelihoods.

Tokyo Electric Power Co. (Tepco), the utility company that runs the Fukushima plant and drew fierce criticism for its handling of the disaster, says the situation has improved greatly.

“In the last five years, radiation levels have been reduced substantially, and we can say that the plant is stable now,” said Akira Ono, the Tepco plant superintendent.

Efforts to contain the contamination have progressed, according to Tepco, including the completion Tuesday of a subterranean “ice wall” around the plant that, once operational, is meant to freeze the ground and stop leakage. Moves to decommission the plant — a process that could take 30 or 40 years, Ono estimated — are getting underway.

People will be allowed to return to their homes in the nearby town of Naraha next month and to Tomioka, even closer to the plant, next year. For now, Tomioka and neighboring Okuma remain ghost towns, lined with convenience stores, fast-food restaurants and gambling parlors that haven’t had a customer in five years. Bicycles lean near front doors, and flowerpots sit empty on windowsills.

A sign on the road to the plant showed a radiation reading of 3.37 microsieverts per hour, at the upper end of safe. At a viewing spot overlooking the reactor buildings, it shot past 200, a level at which prolonged exposure could be dangerous. Both readings are hundreds of times lower than they were a couple of years ago.

After about 20 minutes at the viewing spot, a Tepco official bustled visiting reporters, wearing protective suits, onto a bus. “We don’t want you out here too long,” he said. Below, men continued working on the site.

But one huge question remains: What is to be done with all the radioactive material?

There’s the groundwater that is flowing into the reactor buildings, where it becomes contaminated. It has been treated — Tepco says it can remove 62 nuclides from the water, including strontium, which can burrow into bones and irradiate tissue. It cannot filter out tritium, a radioactive isotope of hydrogen that can be used to make nuclear bombs but is not considered especially harmful to humans.

The water initially was stored in huge bolted tanks in the aftermath of the disaster, but the tanks have leaked highly contaminated radioactive water into the sea on an alarming number of occasions.

Now Tepco is building more-secure welded tanks to hold the water, theoretically for up to 20 years. There are now about 1,000 tanks holding 750,000 tons of contaminated water, with space for 100,000 tons more. The company says it hopes to increase capacity to 950,000 tons within a year or two, as well as halve the amount of water that needs to be stored from the current 300 tons per day.

As part of those efforts, Tepco built the 1,500-yard-long ice wall around the four reactor buildings to freeze the soil and keep groundwater from getting in and becoming radioactive. Company officials hoped to have the wall working next month; on Wednesday, however, Japan’s nuclear watchdog blocked the plan, saying the risk of leakage was still too high.

The options for getting rid of the contaminated water include trying to remove the tritium from it before letting it run into the sea; evaporating it, as was done at Three Mile Island, the Pennsylvania plant that melted down in 1979; and injecting it deep into the ground, using technology similar to that used to extract shale gas. A government task force is considering which option to choose. ”

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by Anna Fifield

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CNN:

” Tokyo (CNN) — Cleaning up Japan’s Fukushima Daiichi nuclear plant, which suffered catastrophic meltdowns after an earthquake and tsunami hit in 2011, may take up to 40 years.

The crippled nuclear reactor is now stable but the decommissioning process is making slow progress, says the plant’s operator Tokyo Electric Power Co, better known as TEPCO.

“If I may put this in terms of mountain climbing, we’ve just passed the first station on a mountain of 10 stations,” said Akira Ono, head of the Fukushima plant.

It’s almost five years since the earthquake and the tsunami it triggered killed more than 15,000 people and destroyed coastal towns on March 11, 2011.

TEPCO has attracted fierce criticism for its handling of the disaster.

Biggest challenge

The biggest obstacle to closing down the plant permanently is removing all the melted nuclear fuel debris from three reactors, Ono told reporters after a press tour of the plant this week.

But TEPCO says it is in the dark about the current state of the debris.

Hydrogen gas explosions and nuclear meltdowns released lethal levels of radiation in 2011.

Though radiation levels have fallen, they still prevent workers from accessing the reactor buildings, making it hard to survey the condition of the destroyed facilities and molten fuel debris.

What to do with the large volume of contaminated water now stored at the plant is another problem.

Around 300 to 400 tons of contaminated water is generated every day as groundwater flows into the plant filled with radioactive debris.

To contain the tainted water, TEPCO pumps up the water and stores it in tanks, adding a new tank every three to four days. There are 1,000 tanks today containing 750,000 tons of contaminated water.

However, decontamination elsewhere on the premises is making headway. Workers now only need dust masks for a large part of the plant.

For outsiders, this appears to be only small progress. But it makes a huge difference for workers who used to wear full masks for outside clean-up and construction work.

Last year in October, Japan confirmed the first case of cancer in a Fukushima worker.

While agreeing to cover the worker’s treatment costs, the government stopped short of recognizing the scientific link between the cancer and his work. “

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Four years on from nuclear disaster, Fukushima workers get own rest area — Reuters

” Tokyo Electric Power Co., the utility that runs the destroyed Fukushima nuclear plant, has opened a rest area and canteen for cleanup workers, more than four years after the world’s worst nuclear disaster since Chernobyl.

The center, on the western edge of the power station, opened on Sunday, replacing pre-fabricated facilities used by workers since an earthquake and tsunami triggered multiple meltdowns on March 11, 2011, forcing more than 160,000 residents to flee from nearby towns.

It will serve up to 3,000 meals a day and provide rest space for around 1,200 workers, Tokyo Electric said during a press tour on Thursday. Contractors on breaks from their work ate curries, noodles and rice bowls in the large canteen.

“The old areas were unclean. People ate rice or bread as they walked around or when sitting in corridors,” said contractor Masahiro Miyura. “This place is better.”

Tokyo Electric has been widely criticized for its treatment of workers and handling of the cleanup, which is expected to take decades. A Reuters investigation in 2013 found widespread labor abuses, including workers who said their pay was skimmed and spoke of scant scrutiny of working conditions at the plant.

Hundreds of bags of radioactive debris are stored in nearby fields, while the government seeks to establish a storage site in the shadow of the plant and in the face of local opposition.

There have been two fatal accidents at the plant since March last year, including a contractor who died after falling into a water storage tank in January.

Data released by the company in April showed the number of accidents and cases of heat stroke involving Fukushima workers doubled to 64 in 2014. Figures for the year to date have not been released.

Tokyo Electric has repeatedly promised to improve conditions for workers, who in the immediate aftermath of the 2011 disaster lacked sufficient radiation suits and accommodation.

“We have taken various steps to cut accidents, including Tokyo Electric itself working more with contractors on the ground,” Akira Ono, Fukushima plant manager, told Reuters.

Almost 7,000 workers, provided by around 800 mostly small contractors, are involved in decontaminating and decommissioning the plant.

Japan began encouraging residents to return to homes 20 km (12 miles) from the plant last year, but many residents have mixed feelings about returning to abandoned towns. ”

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