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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Airborne radiation near Fukushima nuke plant still far higher than gov’t max — The Mainichi

” Airborne radiation in “difficult to return” zones around the Fukushima No. 1 nuclear plant was as high as around 8.48 microsieverts per hour as of summer last year, according to data presented by the government nuclear watchdog on Jan. 17.

The Nuclear Regulation Authority (NRA) released the results of the July-September 2017 measurements at a regular meeting on the day. The highest reading was taken in Futaba, Fukushima Prefecture — one of the municipalities hosting the Fukushima No. 1 plant.

Following the March 2011 triple meltdown, the government set a long-term radiation exposure limit of 1 millisievert per year, which breaks down to an hourly airborne radiation dose of 0.23 microsieverts.

The NRA took airborne radiation readings in the Fukushima Prefecture towns of Futaba, Okuma, Namie and Tomioka, and the village of Katsurao. The highest reading registered in the previous year’s survey was 8.89 microsieverts per hour, in Katsurao.

Some of the NRA members at the Jan. 17 meeting pointed to study results showing that human exposure doses are relatively small compared to airborne doses. Regarding the calculation that an annual dose of 1 millisievert is equivalent to hourly exposure of 0.23 microsieverts, NRA Chairman Toyoshi Fuketa stated, “That was decided right at the start of the nuclear disaster, so it can’t be helped that it’s a cautious number.” He added, “If we don’t revise (that calculation) properly, it could hinder evacuees’ return home.” “

by The Mainichi

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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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Government and utilities shaken by high court challenge to public trust in Japan’s nuclear authority — The Japan Times

” Wednesday’s ruling by the Hiroshima High Court halting the planned restart of a nuclear reactor in Ehime Prefecture has cast doubt on the judgment of Japan’s Nuclear Regulation Authority — which had approved the restart under stricter post-Fukushima guidelines — shocking the government and utilities across the nation.

The ruling deals a heavy blow to a plan by Prime Minister Shinzo Abe’s administration to bring more reactors back online, and is sure to prompt the government and utilities to keep a closer eye on similar cases continuing across the country.

Yuichi Kaido, a lawyer representing local residents, called the ruling the “most important” since the Fukushima nuclear disaster, spurred by the Great East Japan Earthquake and tsunami on March 11, 2011.

About 40 court cases — including those seeking injunctions — were filed in the wake of the Fukushima meltdown disaster. But while district courts have ordered some reactors stopped, each shutdown decision has been overturned by a high court.

“This is the first time (plaintiffs) have won at the high court level,” Kaido said at a news conference in Tokyo. He said the ruling may signal a turn of the tide.

Wednesday’s ruling was also noteworthy for touching on the risk of volcanic eruption.

“The possibility of heated rock and volcanic ash reaching the reactor cannot be evaluated as small. The location is not suitable” for a nuclear reactor, said presiding Judge Tomoyuki Nonoue in handing down the ruling. The reactor affected is the No. 3 unit at Shikoku Electric Power Co.’s Ikata plant, which is located about 130 kilometers from the caldera of the volcanically active Mount Aso in Kumamoto Prefecture.

“The effect that volcanic ash may have on reactors nationwide is underrated,” Kaido said.

Government officials were quick to attempt to play down the risk. “It’s just a court ruling. The government’s position to seek the restart for reactors approved by the (Nuclear Regulation Authority) remains unchanged,” said a senior trade ministry official.

The central government’s target for power generations calls for 20 percent to 22 percent of the nation’s supply to be contributed by nuclear reactors by 2030.

Nuclear Regulation Authority Chairman Toyoshi Fuketa told a news conference that the high court decision would not influence its ongoing and future safety screenings of other reactors.

“We will just fulfill the role of a regulator,” Fuketa said.

But the reality is that utilities have been seeking to convince municipalities that reactors cleared by the watchdog under the tougher guidelines are safe.

“I’m worried that it could create negative momentum,” said an industry official.

For Shikoku Electric, the blocked restart will mean a spike in fuel costs as it will be forced to rely mainly on non-nuclear power generation.

“While the nuclear reactors are suspended, we will need to rely on thermal power, which means we will need to shoulder a ¥3.5 billion loss per month for fuel,” an executive of the utility said at a news conference on Wednesday.

Other utilities are facing similar constraints. Kyushu Electric Power Co. aims to restart two reactors at its Genkai plant in Saga Prefecture, but local residents have filed an injunction seeking to halt the move. A Kyushu Electric executive said he was “surprised at the unexpected ruling” on the Ikata plant.

Meanwhile, the response of residents in Ehime Prefecture was mixed.

One man voiced concern over the ruling’s potential to damage the local economy. The man, who runs a lodging business, said the town accommodated several hundred nuclear power plant workers a year before the Fukushima disaster.

“Ikata is a town of nuclear power,” he said. “I feel that (the ruling) has left locals behind.”

Another resident, however, welcomed the move as a judicial “breakthrough.” ”

by Kyodo, The Japan Times

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High-priced Fukushima ice wall nears completion, but effectiveness doubtful — The Mainichi

” A subterranean ice wall surrounding the nuclear reactors at the stricken Fukushima No. 1 Nuclear Power Plant to block groundwater from flowing in and out of the plant buildings has approached completion.

Initially, the ice wall was lauded as a trump card in controlling radioactively contaminated water at the plant in Fukushima Prefecture, which was crippled by meltdowns in the wake of the March 2011 Great East Japan Earthquake and tsunami. But while 34.5 billion yen from government coffers has already been invested in the wall, doubts remain about its effectiveness. Meanwhile, the issue of water contamination looms over decommissioning work.

In a news conference at the end of July, Naohiro Masuda, president and chief decommissioning officer of Fukushima Daiichi Decontamination & Decommissioning Engineering Co., stated, “We feel that the ice wall is becoming quite effective.” However, he had no articulate answer when pressed for concrete details, stating, “I can’t say how effective.”

The ice wall is created by circulating a coolant with a temperature of minus 30 degrees Celsius through 1,568 pipes that extend to a depth of 30 meters below the surface around the plant’s reactors. The soil around the pipes freezes to form a wall, which is supposed to stop groundwater from flowing into the reactor buildings where it becomes contaminated. A total of 260,000 people have worked on creating the wall. The plant’s operator, Tokyo Electric Power Co. (TEPCO) began freezing soil in March last year, and as of Aug. 15, at least 99 percent of the wall had been completed, leaving just a 7-meter section to be frozen.

Soon after the outbreak of the nuclear disaster, about 400 tons of contaminated water was being produced each day. That figure has now dropped to roughly 130 tons. This is largely due to the introduction of a subdrain system in which water is drawn from about 40 wells around the reactor buildings. As for the ice wall, TEPCO has not provided any concrete information on its effectiveness. An official of the Secretariat of the Nuclear Regulation Authority (NRA) commented, “The subdrain performs the primary role, and the ice wall will probably be effective enough to supplement that.” This indicates that officials have largely backtracked from their designation of the ice wall as an effective means of battling contaminated water, and suggests there is unlikely to be a dramatic decrease in the amount of decontaminated groundwater once the ice wall is fully operational.

TEPCO ordered construction of the ice wall in May 2013 as one of several plans proposed by major construction firms that was selected by the government’s Committee on Countermeasures for Contaminated Water Treatment. In autumn of that year Tokyo was bidding to host the 2020 Olympic and Paralympic Games, and the government sought to come to the fore and underscore its measures to deal with contaminated water on the global stage.

Using taxpayers’ money to cover an incident at a private company raised the possibility of a public backlash. But one official connected with the Committee on Countermeasures for Contaminated Water Treatment commented, “It was accepted that public funds could be spent if those funds were for the ice wall, which was a challenging project that had not been undertaken before.” Small-scale ice walls had been created in the past, but the scale of this one — extending 1.5 kilometers and taking years to complete — was unprecedented.

At first, the government and TEPCO explained that an ice wall could be created more quickly than a wall of clay and other barriers, and that if anything went wrong, the wall could be melted, returning the soil to its original state. However, fears emerged that if the level of groundwater around the reactor buildings drops as a result of the ice wall blocking the groundwater, then tainted water inside the reactor buildings could end up at a higher level, causing it to leak outside the building. Officials decided to freeze the soil in stages to measure the effects and effectiveness of the ice wall. As a result, full-scale operation of the wall — originally slated for fiscal 2015 — has been significantly delayed.

Furthermore, during screening by the NRA, which had approved the project, experts raised doubts about how effective the ice wall would be in blocking groundwater. The ironic reason for approving its full-scale operation, in the words of NRA acting head Toyoshi Fuketa, was that, “It has not been effective in blocking water, so we can go ahead with freezing with peace of mind” — without worrying that the level of groundwater surrounding the reactor buildings will decrease, causing the contaminated water inside to flow out.

Maintaining the ice wall will cost over a billion yen a year, and the radiation exposure of workers involved in its maintenance is high. Meanwhile, there are no immediate prospects of being able to repair the basement damage in the reactor buildings at the crippled nuclear plant.

Nagoya University professor emeritus Akira Asaoka commented, “The way things stand, we’ll have to keep maintaining an ice wall that isn’t very effective. We should consider a different type of wall.”

In the meantime, TEPCO continues to be plagued over what to do with treated water at the plant. Tainted water is treated using TEPCO’s multi-nuclide removal equipment to remove 62 types of radioactive substances, but in principle, tritium cannot be removed during this process. Tritium is produced in nature through cosmic rays, and nuclear facilities around the world release it into the sea. The NRA takes the view that there is no problem with releasing treated water into the sea, but there is strong resistance to such a move, mainly from local fishing workers who are concerned about consumer fears that could damage their businesses. TEPCO has built tanks on the grounds of the Fukushima No. 1 plant to hold treated water, and the amount they hold is approaching 800,000 metric tons.

In mid-July, TEPCO Chairman Takashi Kawamura said in an interview with several news organizations that a decision to release the treated water into the sea had “already been made.” A Kyodo News report on his comment stirred a backlash from members of the fishing industry. TEPCO responded with an explanation that the chairman was not stating a course of action, but was merely agreeing with the view of the NRA that there were no problems scientifically with releasing the treated water. However, the anger from his comment has not subsided.

Critical opinions emerged in a subsequent meeting that the Ministry of Economy, Trade and Industry held in the Fukushima Prefecture city of Iwaki at the end of July regarding the decontamination of reactors and the handling of contaminated water. It was pointed out that prefectural residents had united to combat consumer fears and that they wanted officials to act with care. One participant asked whether the TEPCO chairman really knew about Fukushima.

The ministry has been considering ways to handle the treated water, setting up a committee in November last year that includes experts on risk evaluation and sociology. As of Aug. 15, five meetings had been held, but officials have yet to converge on a single opinion. “It’s not that easy for us to say, ‘Please let us release it.’ It will probably take some time to reach a conclusion,” a government official commented. “

by The Mainichi

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NRA: Ice wall effects ‘limited’ at Fukushima nuclear plant — The Asahi Shimbun

” Citing “limited, if any effects,” the Nuclear Regulation Authority said a highly touted “frozen soil wall” should be relegated to a secondary role in reducing contaminated groundwater at the Fukushima No. 1 nuclear plant.

The government spent 34.5 billion yen ($292 million) to build the underground ice wall to prevent groundwater from mixing with radioactive water in four reactor buildings at the crippled plant.

But the NRA, Japan’s nuclear watchdog, concluded on Dec. 26 that the wall has been ineffective in diverting the water away from the buildings. It said that despite the low rainfall over the past several months, the amount of groundwater pumped up through wells outside the frozen wall on the seaside is still well above the reduction target.

It urged the plant operator, Tokyo Electric Power Co., to tackle the groundwater problem primarily with pumps, not the ice wall.

In response, TEPCO at the meeting said that by next autumn, it will double its capacity to pump up groundwater from the current 800 tons a day.

About 400 tons of groundwater enters the damaged reactor buildings each day and mixes with highly radioactive water used to cool melted nuclear fuel.

The ice wall project, compiled by the industry ministry in May 2013, was seen as a fundamental solution to this problem that has hampered TEPCO’s cleanup efforts since the triple meltdown in March 2011.

Some 1,568 frozen ducts were inserted 30 meters deep into the ground to circulate a liquid at 30 degrees below zero. The freezing process was supposed to have created a solid wall of ice that could block the groundwater.

TEPCO began freezing the wall on the seaside in March. It announced in the middle of October that the temperature at all measuring points in that area was below zero.

Before the frozen wall project, TEPCO had to pump up about 300 tons of contaminated water a day. The daily volume dropped to about 130 tons in recent weeks, but it was still well beyond the target of 70 tons.

Still, TEPCO boasted about the effectiveness of the ice wall at the meeting with the NRA on Dec. 26, saying, “We are seeing certain results.”

The NRA, however, said the results are limited at best.

Toyoshi Fuketa, an NRA commissioner, already warned TEPCO in October that it cannot expect the ice wall to be highly effective in containing the groundwater.

“Pumping up groundwater through wells should be the main player because it can reliably control the groundwater level,” Fuketa said at that time. “The ice wall will play a supporting role.”

That sentiment was echoed at the Dec. 26 meeting.

However, the NRA approved the utility’s plan to begin freezing dirt for a wall on the mountain side of the nuclear plant.

The NRA was previously concerned about risks posed by the new ice wall. If it totally blocked groundwater from the mountain side, the water level within the frozen soil near the reactors could become too low, allowing highly contaminated water inside the reactor buildings to flow out more rapidly.

The NRA urged TEPCO to delay work on the mountain side until the ice wall on the seaside portion proved effective.

But it reversed its stance, saying a sharp drop in the groundwater level is unlikely based on the ineffectiveness of the existing ice wall.

“The frozen wall on the mountain side will not be able to block groundwater because the wall on the seaside was also unable to do so,” Fuketa said. “It will not be very dangerous to freeze the wall on the mountain side as long as the work is carried out carefully.”

TEPCO will start the work to freeze the ducts at five sections as early as next year.

Masashi Kamon, professor emeritus of geotechniques at Kyoto University, expressed skepticism about continuing the ice wall project without a full scrutiny of the underground conditions.

“Soil around the tunnels for underground pipes must be hard to freeze,” he said. “TEPCO should find out the conditions of the very bottom of the ice wall by drilling at least one section. It is questionable to continue with the project without a review.” ”

by Kohei Tomida

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