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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Clearing the radioactive rubble heap that was Fukushima Daiichi, 7 years on — Scientific American

” Seven years after one of the largest earthquakes on record unleashed a massive tsunami and triggered a meltdown at Japan’s Fukushima Daiichi nuclear power plant, officials say they are at last getting a handle on the mammoth task of cleaning the site before it is ultimately dismantled. But the process is still expected to be a long, expensive slog, requiring as-yet untried feats of engineering—and not all the details have yet been worked out.

When the disaster knocked out off- and on-site power supplies on March 11, 2011, three of the cooling systems for the plant’s four reactor units were disabled. This caused the nuclear fuel inside to overheat, leading to a meltdown and hydrogen explosions that spewed out radiation. The plant’s operator, Tokyo Electric Power Co. (TEPCO), responded by cooling the reactors with water, which continues today. Meanwhile thousands of people living in the surrounding area were evacuated and Japan’s other nuclear plants were temporarily shut down.

In the years since the disaster and the immediate effort to stanch the release of radioactive material, officials have been working out how to decontaminate the site without unleashing more radiation into the environment. It will take a complex engineering effort to deal with thousands of fuel rods, along with the mangled debris of the reactors and the water used to cool them. Despite setbacks, that effort is now moving forward in earnest, officials say. “We are still conducting studies on the location of the molten fuel, but despite this we have made the judgment that the units are stable,” says Naohiro Masuda, TEPCO’s chief decommissioning officer for Daiichi.

Completely cleaning up and taking apart the plant could take a generation or more, and comes with a hefty price tag. In 2016 the government increased its cost estimate to about $75.7 billion, part of the overall Fukushima disaster price tag of $202.5 billion. The Japan Center for Economic Research, a private think tank, said the cleanup costs could mount to some $470 billion to $660 billion, however.

Under a government roadmap, TEPCO hopes to finish the job in 30 to 40 years. But some experts say even that could be an underestimate. “In general, estimates of work involving decontamination and disposal of nuclear materials are underestimated by decades,” says Rod Ewing, a professor of nuclear security and geological sciences at Stanford University. “I think that we have to expect that the job will extend beyond the estimated time.”

The considerable time and expense are due to the cleanup being a veritable hydra that involves unprecedented engineering. TEPCO and its many contractors will be focusing on several battlefronts.

Water is being deliberately circulated through each reactor every day to cool the fuel within—but the plant lies on a slope, and water from precipitation keeps flowing into the buildings as well. Workers built an elaborate scrubbing system that removes cesium, strontium and dozens of other radioactive particles from the water; some of it is recirculated into the reactors, and some goes into row upon row of giant tanks at the site. There’s about one million tons of water kept in 1,000 tanks and the volume grows by 100 tons a day, down from 400 tons four years ago.

To keep more water from seeping into the ground and being tainted, more than 90 percent of the site has been paved. A series of drains and underground barriers—including a $325-million* supposedly impermeable “wall” of frozen soil—was also constructed to keep water from flowing into the reactors and the ocean. These have not worked as well as expected, though, especially during typhoons when precipitation spikes, so groundwater continues to be contaminated.

Despite the fact contaminated water was dumped into the sea after the disaster, studies by Japanese and foreign labs have shown radioactive cesium in fish caught in the region has fallen and is now within Japan’s food safety limits. TEPCO will not say when it will decide what to do with all the stored water, because dumping it in the ocean again would invite censure at home and abroad—but there are worries that another powerful quake could cause it to slosh out of the tanks.

Fuel Mop-up

A second major issue at Fukushima is how to handle the fuel¾the melted uranium cores as well as spent and unused fuel rods stored at the reactors. Using robotic probes and 3-D imaging with muons (a type of subatomic particle), workers have found pebbly deposits and debris at various areas inside the primary containment vessels in the three of the plant’s reactor units. These highly radioactive remains are thought to be melted fuel as well as supporting structures. TEPCO has not yet worked out how it can remove the remains, but it wants to start the job in 2021. There are few precedents for the task. Lake Barrett—director of the Three Mile Island nuclear plant during its decommissioning after a partial meltdown at the Middletown, Pa., facility in 1979—says TEPCO will use robots to remotely dig out the melted fuel and store it in canisters on-site before shipping to its final disposal spot. “This is similar to what we did at Three Mile Island, just much larger and with much more sophisticated engineering because their damage is greater than ours was,” Barrett says. “So although the work is technically much more challenging than ours was, Japan has excellent technological capabilities, and worldwide robotic technology has advanced tremendously in the last 30-plus years.”

Shaun Burnie, senior nuclear specialist with Greenpeace Germany, doubts the ambitious cleanup effort can be completed in the time cited, and questions whether the radioactivity can be completely contained. Until TEPCO can verify the conditions of the molten fuel, he says, “there can be no confirmation of what impact and damage the material has had” on the various components of the reactors—and therefore how radiation might leak into the environment in the future.

Although the utility managed to safely remove all 1,533 fuel bundles from the plant’s unit No. 4 reactor by December 2014, it still has to do the same for the hundreds of rods stored at the other three units. This involves clearing rubble, installing shields, dismantling the building roofs, and setting up platforms and special rooftop equipment to remove the rods. Last month a 55-ton dome roof was installed on unit No. 3 to facilitate the safe removal of the 533 fuel bundles that remain in a storage pool there. Whereas removal should begin at No. 3 sometime before April 2019, the fuel at units No. 1 and 2 will not be ready for transfer before 2023, according to TEPCO. And just where all the fuel and other radioactive solid debris on the site will be stored or disposed of long-term has yet to be decided; last month the site’s ninth solid waste storage building, with a capacity of about 61,000 cubic meters, went into operation.

As for what the site itself might look like decades from now, cleanup officials refuse to say. But they are quick to differentiate it from the sarcophagus-style containment of the 1986 Chernobyl catastrophe in the Soviet Union, in what is now Ukraine. Whereas the Chernobyl plant is sealed off and the surrounding area remains off-limits except for brief visits—leaving behind several ghost towns—Japanese officials want as many areas as possible around the Daiichi site to eventually be habitable again.

“To accelerate reconstruction and rebuilding of Fukushima as a region, and the lives of locals, the key is to reduce the mid- and long-term risk,” says Satoru Toyomoto, director for international issues at the Ministry of Economy, Trade and Industry’s Nuclear Accident Response Office. “In that regard, keeping debris on the premises without approval is not an option.” ”

by Tim Hornyak, Scientific American

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Experts: Fukushima must do more to reduce radioactive water — U.S. News

Here is a good article written by Mari Yamaguchi that explains the state of contaminated water at the Fukushima Daiichi plant. Experts say that the ice wall that was built to keep groundwater from coming into the power plant and becoming contaminated with radioactivity is only half effective. A conventional drainage system also collects water from wells dug around the plant and pumps it out before it becomes contaminated. This water is stored in about 1,000 storage tanks near the facility. Read more about the construction, operation and maintenance costs that are coming out of the taxpayer’s pocket.

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Seven Years After: Radioactive debris piling up at Fukushima interim facility — The Asahi Shimbun

” FUTABA, Fukushima Prefecture–Stacks of soil and other waste contaminated by the Fukushima nuclear disaster continue to grow at an interim storage facility here.

Black bags filled with radioactive debris collected during decontamination work in various locations in the prefecture have been brought to the facility since October, when operations started.

Heavy machinery is used to stack the bags, and green sheets now cover some of the piles.

The town of Futaba co-hosts the crippled Fukushima No. 1 nuclear plant. The interim facility is expected to eventually cover about 1,600 hectares of land in Futaba and Okuma, the other co-host of the plant.

The government has acquired 801 hectares as of Jan. 29, and 70 percent of that space is already covered with contaminated debris.

Negotiations between the government and landowners are continuing for the remaining hectares.

The government plans to move the contaminated debris to a final disposal site outside the prefecture by March 2045. However, it has had difficulties finding local governments willing to accept the waste. ”

by Tetsuro Takehana, The Asahi Shimbun

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Japan’s plutonium glut casts a shadow on renewed nuclear deal — Nikkei Asian Review

” TOKYO — The decision Jan. 16 to automatically extend a nuclear agreement with the U.S. came as a relief to a Japanese government worried about the prospect of renegotiating the basis for a cornerstone of its energy policy. But friction remains over a massive store of plutonium that highlights the problems with the nation’s ambitious nuclear energy plans.

The nuclear fuel cycle pursued by Japan’s government and power companies centers on recovering uranium and plutonium from spent fuel for reuse in reactors. This is made possible by the unique agreement with the U.S. that lets Japan make plutonium. The radioactive element can be used in nuclear weapons, so its production is generally tightly restricted.

“The agreement forms part of the foundation of Japan’s nuclear power activities,” said Hiroshige Seko, minister of economy, trade and industry, in comments to reporters Friday. “It’s important from the standpoint of the Japan-U.S. relationship.”

America began sharing its advanced atomic energy technology with other nations in the 1950s, aiming to promote its peaceful use. Washington remains hugely influential in setting ground rules for military applications of nuclear material, including with regard to reprocessing. Countries including South Korea have sought special arrangements like Japan’s.

The lack of fuss over the renewal of the agreement, which had been due to expire this coming July, has masked concerns expressed behind the scenes. A Japanese official visiting Washington in December was asked by a U.S. nuclear policymaker about Japan’s oversight of its plutonium stockpile.

Japan has amassed roughly 47 tons of plutonium stored inside and outside the country — enough for some 6,000 nuclear warheads. With the nation’s nuclear power plants gradually taken offline after the March 2011 Fukushima Daiichi disaster, and progress on restarting them sluggish, Japan has been left with no real way to whittle down a pile drawing international scrutiny.

Washington ultimately did not ask to change the nuclear agreement, which after the expiration date can be terminated by either side with six months’ notice. Given the tense regional security situation, including North Korea’s missile advances, “Japan and the U.S. apparently didn’t want the world to see friction between them over nuclear power,” said a Japanese government insider in contact with Washington.

Tokyo’s relief at the lack of American demands is dampened by the awareness that the deal could be scrapped at any time. “It’s more unstable than before,” an industry ministry official acknowledged.

The best-case scenario for Japan would have been securing an agreement that set a new expiration date. But any such change would have had to go through the U.S. Congress, where lawmakers supporting nuclear nonproliferation might not have welcomed giving Japan — which already has no prospect of using up its existing supply — carte blanche to keep reprocessing. This risk is likely why Washington opted for automatic extension of the existing agreement.

The precursor to the current deal, signed in 1955, let Japan use American technology to kick-start its own atomic energy industry. A new agreement in 1968 permitted reprocessing of spent fuel with U.S. consent. A 1988 revision gave blanket permission for reprocessing for peaceful applications.

But the nuclear fuel cycle policy this enabled has stalled amid chronic problems at key facilities. The Japanese government decided in 2016 to scrap the Monju plutonium-fueled experimental fast breeder reactor. And a reprocessing facility in northern Japan that would be critical to producing plutonium fuel usable by conventional reactors has faced repeated delays that have pushed back the completion date from 1997 to 2021.

Reducing Japan’s plutonium stockpile will be vital to assuaging international concerns. Seko asserted that plutonium consumption will pick up again as the Nuclear Regulation Authority clears more reactors to restart.

But this may not work as well as Tokyo hopes. Just five reactors have met the stricter safety standards imposed in the wake of the Fukushima Daiichi meltdowns, and not all of these use plutonium.

The nuclear watchdog said Jan. 16 that it will devise new guidelines to better adhere to the government’s principle of not possessing plutonium without a specific purpose. Critics of Japan’s plutonium production will likely not be satisfied without a convincing, reality-based plan to deal with the issue. ”

by Kazunari Hanawa and Takashi Tsuji, Nikkei writing staff

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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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