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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Fukushima’a other big problem: A Million tons of radioactive water — Wired

” The tsunami-driven seawater that engulfed Japan’s Fukushima Daiichi nuclear plant has long since receded. But plant officials are still struggling to cope with another dangerous flood: the enormous amounts of radioactive water the crippled facility generates each day. More than 1 million tons of radiation-laced water is already being kept on-site in an ever-expanding forest of hundreds of hulking steel tanks—and so far, there’s no plan to deal with them.

The earthquake and tsunami that hammered Fukushima on March 11, 2011 triggered meltdowns in three of its six reactors. That left messes of intensely radioactive fuel somewhere loose in the reactor buildings—though no one knows exactly where. What is known, however, is that every day, as much as much as 150 tons of groundwater percolates into the reactors through cracks in their foundations, becoming contaminated with radioactive isotopes in the process.

To keep that water from leaking into the ground or the Pacific, Tepco, the giant utility that owns the plant, pumps it out and runs it through a massive filtering system housed in a building the size of a small aircraft hangar. Inside are arrays of seven-foot tall stainless steel tubes, filled with sand grain-like particles that perform a process called ion exchange. The particles grab on to ions of cesium, strontium, and other dangerous isotopes in the water, making room for them by spitting out sodium. The highly toxic sludge created as a byproduct is stored elsewhere on the site in thousands of sealed canisters.

This technology has improved since the catastrophe. The first filtering systems, installed just weeks after the disaster by California-based Kurion Inc. (which has since been bought by Veolia, a French resource management company), only caught cesium, a strong gamma radiation emitter that makes it the most dangerous of the isotopes in the water. The tubes in those arrays were filled with highly modified grains of naturally occurring volcanic minerals called zeolites. By 2013, the company developed entirely artificial particles—a form of titano silicate—that also grab strontium.

The filters, however, don’t catch tritium, a radioactive isotope of hydrogen. That’s a much trickier task. Cesium and strontium atoms go into solution with the water, like sugar in tea; but tritium can bond with oxygen just like regular hydrogen, rendering the water molecules themselves radioactive. “It’s one thing to separate cesium from water, but how do you separate water from water?” asks John Raymont, Kurion’s founder and now president of Veolia’s nuclear solutions group. The company claims to have developed a system that can do the job, but Tepco has so far balked at the multi-billion dollar cost.

So for now, the tritiated water is pumped into a steadily growing collection of tanks. There are already hundreds of them, and Tepco has to start building a new one every four days.

Tepco has at least reduced the water’s inflow. As much as 400 tons per day was gushing in just a couple of years ago. In an effort to keep the groundwater from getting in, Tepco has built a network of pumps, and in 2016 installed an underground “ice wall”—a $300 million subterranean fence of 30-yard-long rods through which tons of sub-zero brine is pumped, freezing the surrounding earth. All of which helps, but hasn’t solved the problem.

Tritium is far less dangerous than cesium—it emits a weaker, lower-energy form of radiation. Still, all that tritiated water can’t just be stored indefinitely. “Some of those tanks and pipes will eventually fail. It’s inevitable,” says Dale Klein, a former head of the US Nuclear Regulatory Commission who has been consulting with Tepco since the early days following the disaster. (In fact, hundreds of tons of water leaked out of the tanks in 2013 and 2014, sparking an international outcry. Tepco has since improved their design.)

Klein, among others, believes that the concentrations of tritium are low enough that the water can safely be released into the sea. “They should dilute and dispose of it,” he says. “It would be better to have a controlled release than an accidental one.”

But the notion of dumping tons of radioactive water into the ocean is understandably a tough sell. Whatever faith the Japanese public had left in Tepco took a further beating in the first couple of years after the meltdowns, when several investigations forced the company to acknowledge they had underreported the amount of radiation released during and after the disaster. Japan’s fishing industry raises a ruckus whenever the idea of dumping the tritiated water is broached; they already have to contend with import restrictions imposed by neighboring countries worried about eating contaminated fish. Japan’s neighbors including China, Korea, and Taiwan have also objected.

For now, all Tepco can do is keep building tanks, and hope that someone comes up with a solution before they run out of room—or the next earthquake hits. “

by Vince Beiser, Wired

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Is Fukushima doomed to become a dumping ground for toxic waste? — The Guardian

” This month, seven years after the 2011 Fukushima Daiichi reactor meltdowns and explosions that blanketed hundreds of square kilometres of northeastern Japan with radioactive debris, government officials and politicians spoke in hopeful terms about Fukushima’s prosperous future. Nevertheless, perhaps the single most important element of Fukushima’s future remains unspoken: the exclusion zone seems destined to host a repository for Japan’s most hazardous nuclear waste.

No Japanese government official will admit this, at least not publicly. A secure repository for nuclear waste has remained a long-elusive goal on the archipelago. But, given that Japan possesses approximately 17,000 tonnes of spent fuel from nuclear power operations, such a development is vital. Most spent fuel rods are still stored precariously above ground, in pools, in a highly earthquake-prone nation.

Japanese officialdom relentlessly emphasises positive messages regarding Fukushima’s short- and medium-term future, prioritizing economic development and the gradual return of skeptical evacuees to their newly “remediated” communities. Yet the return rate for the least hard-hit communities is only about 15%. Government proclamations regarding revitalisation of the area in and around the exclusion zone intone about jobs but seem geared ominously toward a future with relatively few humans.

The Fukushima prefecture government is currently promoting a plan, dubbed The Innovation Coast, that would transform the unwelcoming region into a thriving sweep of high-tech innovation. Much of the development would be directed towards a “robot-related industrial cluster” and experimental zones like a robot test field.

The test field would develop robots tailored for disaster response and for other purposes on a course simulating a wide range of hurdles and challenges already well represented in Fukushima itself. Large water tanks would contain an array of underwater hazards to navigate, mirroring the wreckage-strewn waters beneath the Fukushima Daiichi plant, where a number of meltdown-remediating underwater robots have met a premature demise in recent years.

Elsewhere on the robot test field, dilapidated buildings and other ruins would serve as a proving ground for land-based disaster-response robots, which must navigate twisted steel rods, broken concrete and other rubble. Engineered runways and surrounding radiation-hit areas would serve as prime territory for testing parlous aerial drones for a range of purposes in various weather conditions – which would be difficult or impossible to achieve elsewhere in relatively densely populated Japan.

The planned site for the test field would link with a secluded test area about 13km south along the coast to coordinate test flights over the exclusion zone’s more or less posthuman terrain.

Naturally, unlike Fukushima’s human residents, robots would be oblivious to the elevated radiation levels found outside the Fukushima Daiichi facility. In addition, prefectural officials have suggested that the exclusion zone environs could play host to a range of other services that don’t require much human intervention, such as long-term archive facilities.

Proud long-time residents of Fukushima, for their part, see all this development as a continued “colonisation” of the home prefecture by Tokyo – a well-worn pattern of outsiders using the zone for their own purposes, as were the utility representatives and officials who built the ill-fated plant in the first place.

Years of colossal decontamination measures have scraped irradiated material from seemingly every forest, park, farm, roadside, and school ground. This 16 million cubic metres of radioactive soil is now stored in provisional sites in and around the exclusion zone, waiting to be moved to an interim storage facility that has hardly been started and for which nearly half of the land has not yet even been leased.

The state has promised to remove all the contaminated soil from Fukushima after 30 years, and government officials have been scrupulous in insisting that this will be the case – for soil. Yet in a nation with about 17,000 tonnes of highly radioactive spent fuel rods and no willing candidates for secure repositories, it is only a matter of time before it becomes possible for politicians to publicly back the idea of transforming the area around Fukushima Daiichi into a secure repository.

Government officials, including those tasked with nuclear waste storage, describe the quintessentially Japanese strategy of saki-okuri, or calculated postponement, in the context of nuclear waste storage. Such perception management is a subtle business, but by quietly and unrelentingly pushing back the day of reckoning – slowly changing the terms of debate – the broadly distasteful prospect of storing Japan’s most dangerous material in its most tragically maltreated region would become gradually less intolerable to Japanese sensibilities.

The expanse of Fukushima in and around the exclusion zone represents an already contaminated area with, since 2011, far fewer residents to protest against such plans. Such a rare opportunity for relatively unopposed intervention in a struggling area will surely prove irresistible to the nuclear lobby.

Fukushima has been marginalised, disenfranchised, and outmanoeuvred for decades. After all, the electricity from Fukushima Daiichi went straight to the capital, not to Fukushima itself, which bore the risks. Since 2011, Fukushima has been saddled with the staggering burden of the meltdown’s aftermath that, despite government PR, will encumber and stigmatise its citizens for at least several decades. ”

by Peter Wynn Kirby, The Guardian

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Regulator urges Tepco to release treated radioactive water from damaged Fukushima No. 1 nuclear plant into the sea — The Japan Times

” A decision should be made sometime this year over whether to release into the sea water containing radioactive tritium from the crisis-hit Fukushima No. 1 nuclear plant, the chief of Japan’s nuclear regulator said Thursday, emphasizing it would pose no danger to human health.

“We will face a new challenge if a decision (about the release) is not made this year,” Nuclear Regulation Authority Chairman Toyoshi Fuketa told Naraha Mayor Yukiei Matsumoto, referring to the more than 1 million tons of coolant water and groundwater that has accumulated at the crippled facility. Naraha is located close to the Fukushima No.1 plant.

Fuketa said releasing the water into the sea after dilution is the only solution, saying “it is scientifically clear that there will be no impact on marine products or to the environment.”

Currently, Fukushima plant operator Tokyo Electric Power Company Holdings Inc. regularly filters contaminated coolant water and ground water from the damaged plant. The processed water is stored in hundreds of water tanks set up within the plant’s compound.

Dangerous radioactive materials are removed during filtration, but tritium — which is difficult to separate from water but relatively harmless to human health — remains.

“(Tepco) has been building new tanks, but it will eventually run out of land,” an NRA official later told The Japan Times.

With limited storage space for water tanks, observers warn that tritium could start leaking from the Fukushima plant.

The nuclear regulator’s chief underlined the need for the government and Tepco to make a decision quickly, saying, “It will take two or three years to prepare for the water’s release into the sea.”

At other nuclear power plants, water containing tritium is routinely dumped into the sea after it is diluted. The regulator has been calling for the release of the water after diluting it to a density lower than standards set by law.

According to the NRA, an average pressured-water reactor for commercial use in Japan usually dumps 60 trillion becquerels of tritium a year into the sea.

Local fishermen are, however, worried about the negative impact from the water discharge — in particular the effect of groundless rumors regarding the safety of marine life near the Fukushima plant. In the face of their opposition, Tepco has not yet reached a decision on how to deal with the stored water.

At the Fukushima plant contaminated water is building up partly because groundwater is seeping into the reactor buildings and mixing with water that has been made radioactive in the process of cooling the damaged reactors.

According to the NRA, there were 650 water tanks within the compound at the Fukushima No. 1 plant as of last month.

The density of tritium in the water ranges from 1 million to 5 million becquerels per liter. Legal restrictions require a nuclear power plant to dump tritium-tainted water after diluting it to 60,000 becquerels per liter, according to the NRA.

On March 11, 2011, tsunami inundated the six-reactor plant, which is located on ground 10 meters above sea level, and flooded its power supply facilities.

Reactor cooling systems were crippled and the Nos. 1 to 3 reactors suffered fuel meltdowns in the world’s worst nuclear catastrophe since the 1986 Chernobyl disaster. ”

by Kyodo, The Japan Times

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For 6,000, the daily bus ride takes them to Fukushima plant — The Asahi Shimbun

” NARAHA, Fukushima Prefecture–Despite the predawn hour, few people are sleeping on a bus that steadily makes its way north on National Route 6.

Some passengers are planning for the work ahead. One is looking forward to chatting with his colleagues. And a few wonder if today will be the day when their annual radiation doses reach the safety limit.

Every day, buses like this take 6,000 workers to the Fukushima No. 1 nuclear power plant. And every day, the same buses take the exhausted and mostly sleeping workers back to their base at the Japan Football Village (J-Village) in Naraha.

Although the Fukushima plant is still decades away from being decommissioned, without this daily routine of the workers who toil amid an invisible danger, the situation at the site would be much more difficult.

407 Daily Bus Rides

One of them, the 49-year-old leader of a group of metal workers from Iwaki, Fukushima Prefecture, has been working at nuclear plants, including the Kashiwazaki-Kariwa power station in Niigata Prefecture, for nearly 20 years.

He was at the Fukushima No. 1 nuclear plant when the Great East Japan Earthquake and tsunami triggered the triple meltdown there in March 2011.

“Nobody can get close to the area where the melted nuclear fuel remains due to high radiation doses,” the man said. “Even if we could approach the area, we would have no way out if something happens. The situation is harsh.”

Those metal workers install tanks for the contaminated water that keeps accumulating at the plant.

Although there are plenty of empty seats, the young workers sit in front and the older workers take the back seats.

Thousands of workers are staying at temporary dormitories set up in J-Village, a soccer training complex.

Tokyo Electric Power Company Holdings Inc., operator of the nuclear plant, hired a local bus company to transport the workers to the plant because securing parking areas near the site has been difficult since the 2011 disaster.

The company provides 407 services a day to and from the plant. Each trip takes about 30 minutes.

The first shuttle bus departs from J-Village at 3:30 a.m., while the last bus leaves the Fukushima plant at 9:45 p.m.

In mid-November amid torrential rain, one bus picked up a man taking shelter under the eaves of a bus stop.

He said he is in charge of managing data related to radiation doses of fittings and other equipment at the plant.

“We have many different types of work here,” the man proudly said.

Also on the way to the nuclear plant, a 53-year-old employee of a security company was thinking about personnel distribution.

Like other workers there, security guards must be replaced when their annual radiation doses reach a certain level set by the government.

He said he has difficulties making ends meet with a limited number of guards who have knowledge about radiation.

Suddenly, the man’s cellphone rings, and the caller orders the deployment of additional security guards to the plant.

A 52-year-old TEPCO employee was on the way to the nearby Fukushima No. 2 nuclear power plant to provide a safety training program for workers, many of whom are victims of the triple disaster.

“I want to convey to workers how precious their lives are and how important safety is in a way that doesn’t make me sound hypocritical,” the employee said.

The triple meltdown has been called a “man-made disaster” caused by the failure of both TEPCO’s management and the government’s regulatory authorities.

The TEPCO employee will use props, such as a ladder, and pretend to be a worker to explain dangerous cases at the No. 1 plant.

Premium Seats

On the trip back to J-Village, a different atmosphere exists on the bus.

Although dazzling sunlight shines through the windows and stunning views of the ocean are available, most of the workers are fast asleep in their wrinkled uniforms.

“Few people stay awake. I don’t even switch on the radio. They must be tired after their work,” said Nobuyuki Kimura, 52, who has driven the shuttle bus for one-and-a-half years.

In Kimura’s bus that departed the plant at 2:30 p.m., all 50 seats and some of the auxiliary seats were filled. The few passengers who stayed awake remained quiet.

By early evening, fewer workers boarded the bus at the plant.

Window seats at the back of the bus are desirable on all rides because they have an enough room for the seats to recline, allowing passengers to cross their legs.

A 21-year-old worker from Iwaki went for a window seat at the back after standing at the front of a line waiting for the bus.

“I can relax sitting here. This is the premium seat,” said the man who collects waste materials, such as boots and socks, at the site.

Although he works in protective gear in an area with high radiation levels, he said he has never thought about quitting his job.

He said he became fed up with school as a junior high school student, and did not bother going to senior high school.

At the age of 18, he joined his current company, and his first assignment was at the Fukushima No. 1 plant.

“I became acquaintances with more and more people. It’s fun to speak with people at work,” he said.

Through his work at the nuclear plant, his weight has dropped from 115 kilograms to 93 kg.

Thirty to 40 years are needed to decommission the Fukushima No. 1 plant, according to the mid- and-long-term roadmap compiled by the government and TEPCO.

To reduce the groundwater flowing into the buildings housing the No. 1 to No. 4 reactors, TEPCO installed coolant pipes this year to create an underground frozen soil wall to divert the water into the ocean.

TEPCO announced in October that the ice wall on the sea side was nearly frozen, but groundwater is believed to be seeping through it.

The utility plans to start removing spent fuel from the No. 3 reactor building in fiscal 2017. It also has plans to begin the daunting task of removing the melted fuel from the No. 1 to No. 3 reactor containment vessels in 2021.

However, extremely high radiation levels have prevented workers from approaching and understanding the condition of the melted fuel. The removal method has yet to be decided.

The estimated cost of work for decommissioning and dealing with the contaminated water has ballooned to 8 trillion yen ($68.1 billion). ”

by Aya Nagatani

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Fukushima N-plant’s impermeable wall is one way to revive local fisheries — The Yomiuri Shimbun

The Yomiuri Shimbun presents an optimistic and rather conservative article on the contaminated water situation at Fukushima No. 1.

” At the port area in front of Tokyo Electric Power Co.’s Fukushima No.1 nuclear power plant, radioactive concentration levels have begun to drastically decrease.

This is because an impermeable wall has been completed that runs along the revetment of the port. This means the risk of contaminated groundwater leaking into the port area has been reduced to nearly zero. Countermeasures against contaminated water have steadily been making progress.

Concentration levels of radioactive substances in the sea outside the port area have now fallen to within the government-set standards for acceptable drinking water. At spots close to the port revetment, concentration levels of all kinds of radioactive substances have also been falling markedly since the completion of the impermeable wall.

These developments will probably be conducive to helping reinvigorate the local fisheries industry, which has been afflicted with harmful rumors. Having confirmed firsthand the effectiveness of the impermeable wall, a representative of the local fisheries industry reportedly called on TEPCO to “inform the public of the current state of things.”

Although the crisis at the Fukushima nuclear plant has had little impact on marine products in the waters near the facility, fishing operations along the coastal areas of Fukushima Prefecture have been conducted only on an experimental basis. Both the government and TEPCO must disseminate information, both at home and abroad, regarding the progress of radiation countermeasures and the improvement of water quality.

Construction work for the impermeable wall commenced in 2012. There were fears, however, that the revetment would leave groundwater with nowhere to go when it was sealed off completely, and it would eventually overflow. The impermeable wall project was suspended, and a section measuring about 10 meters was left unsealed.

So many water tanks

When it became possible in September this year to drain groundwater into the sea after pumping and purifying it, the open section of the wall was sealed.

Although an end to the problem of radioactive material leaking into the sea is now in sight, there are still a number of tasks that must be addressed in dealing with contaminated water. In particular, no time must be wasted in devising measures to effectively cope with events such as heavy rain.

There have been instances of radioactive substances within the plant’s premises mixing with rainwater and flowing into the sea via its drainage system. In the reactor buildings, traces and residue of radioactive substances are still present in many places. Decontamination efforts should be redoubled and sufficient attention paid to ensuring the safety of the workers involved.

Operations to deal with groundwater flowing into the reactor buildings are only half complete. The volume of inflowing groundwater has increased, at times even now, to nearly 400 tons a day. Given that this water is contaminated with radioactive substances, it is of key importance to work out what should be done to reduce it.

An underground bypass is already in place that pumps groundwater before it may be contaminated and drains it into the sea.

Work on building underground walls made of frozen soil around the reactor buildings to block the inflow of groundwater has also been undertaken. After completion of the walls, the inflow of groundwater is expected to decrease to less than 100 tons per day. This work must proceed steadily.

What should be of concern is that the plant’s premises is being crammed with an increasing number of tanks to store purified water. Sooner or later, it will certainly become difficult to secure space for the tanks.

It is considered realistic to drain the purified water into the sea just as other nuclear-related facilities have been doing so. ”

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