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

source

Advertisements

Seismologist testifies Fukushima nuclear disaster preventable — The Mainichi

” TOKYO — A seismologist has testified during the trial of three former executives of Tokyo Electric Power Co. (TEPCO), operator of the tsunami-ravaged nuclear plant, that the nuclear crisis could have been prevented if proper countermeasures had been taken.

“If proper steps had been taken based on a long-term (tsunami) evaluation, the nuclear accident wouldn’t have occurred,” Kunihiko Shimazaki, professor emeritus at the University of Tokyo, told the Tokyo District Court on May 9.

Shimazaki, who played a leading role in working out the national government’s long-term evaluation, appeared at the 11th hearing of the three former TEPCO executives as a witness.

Prosecutors had initially not indicted the three former TEPCO executives. However, after a prosecution inquest panel consisting of members of the public deemed twice that the three deserve prosecution, court-appointed lawyers serving as prosecutors indicted the three under the Act on Committee for Inquest of Prosecution.

Court-appointed attorneys insist that former TEPCO Vice President Sakae Muto, 67, and others postponed implementing tsunami countermeasures based on the long-term evaluation, leading to the disaster.

The government’s Headquarters for Earthquake Research Promotion released its long-term evaluation in 2002 predicting that a massive tsunami could occur along the Japan Trench including the area off Fukushima.

In 2008, TEPCO estimated that a tsunami up to 15.7 meters high could hit the Fukushima No. 1 power station, but failed to reflect the prediction in its tsunami countermeasures at the power station.

The Cabinet Office’s Central Disaster Prevention Council also did not adopt the long-term evaluation in working out its disaster prevention plan.

Shimazaki, who was a member of the Headquarters for Earthquake Research Promotion’s earthquake research panel in 2002, told the court that the Cabinet Office pressured the panel shortly before the announcement of the long-term evaluation to state that the assessment is unreliable. The headquarters ended up reporting in the long-term evaluation’s introduction that there were problems with the assessment’s reliability and accuracy.

In his testimony, Shimazaki pointed out that the Central Disaster Prevention Council decision not to adopt the long-term evaluation led to inappropriate tsunami countermeasures.

With regard to factors behind the council’s refusal to accept the evaluation, Shimazaki stated that he can only think of consideration shown to those involved in the nuclear power industry and politics.

“If countermeasures had been in place based on the long-term evaluation, many lives would’ve been saved,” Shimazaki told the court.

Shimazaki served as deputy chairman of the government’s Nuclear Regulatory Authority after the Fukushima nuclear disaster.

(Japanese original by Epo Ishiyama, City News Department, and Ei Okada, Science & Environment News Department) “

published in The Mainichi

source

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

source

Tepco refused safety agency’s proposal to simulate Fukushima tsunami nine years before meltdown disaster — The Japan Times

” Nine years before the 2011 meltdown crisis at the Fukushima No. 1 nuclear power plant, Tokyo Electric Power Co. turned down a request from the government’s nuclear watchdog for it to conduct a simulation of powerful tsunami that could hit the plant, a court document showed on Tuesday.

Written testimony was submitted to the Chiba District Court on Nov. 24 by Shuji Kawahara, who was head of a team responsible for quake safety issues at the now-defunct Nuclear and Industrial Safety Agency (NISA) — the predecessor of today’s Nuclear Regulation Authority.

Kawahara’s testimony showed that Tepco may have missed an opportunity to examine the possibility of a tsunami disaster almost a decade before such a crisis came to pass in 2011, when massive waves knocked out critical cooling systems at the Fukushima No. 1 plant.

The testimony was submitted as part of a lawsuit filed by Fukushima evacuees seeking compensation from the utility and the central government.

The crippled plant has spewed a massive amount of radioactive material into its surroundings, forcing numerous residents to temporarily evacuate. Many have completely abandoned their hometowns.

Contacted by The Japan Times, Tepco spokesman Norio Okura declined to comment, saying “the matter is related to the ongoing lawsuit.”

In the court documents, Kawahara maintains that NISA asked Tepco to conduct a tsunami simulation in August 2002, highlighting emails that summarize discussions at NISA-Tepco meetings that were sent to related parties later the same month.

NISA made the request because a government expert committee for quake research published on July 31, 2002, a report warning that a major tsunami event could hit anywhere along the Pacific coast of Japan, Kawahara said in the statement.

The report concluded that a major tsunami could hit somewhere along the coastal areas from Tohoku to Chiba Prefecture, with a probability of 20 percent over the next 30 years.

Tepco representatives visited NISA officials on Aug. 5 to discuss the report. But Tepco officials “resisted for 40 minutes” during the meeting and eventually turned down NISA’s request, according to a copy of Kawahara’s written statement, seen by The Japan Times on Tuesday.

In the statement, Kawahara said he believes Tepco rejected the request because “it would take substantial time and expense to carry out a simulation,” and because there was no evidence strongly suggesting such a quake and tsunami could actually hit the Fukushima plant.

Rejecting the proposal, Tepco officials cited a research paper written by two seismologists who played down the possibility of such a quake-tsunami disaster, according to Kawahara.

NISA didn’t override Tepco’s refusal. Kawahara said he believes NISA’s decision at the time was “justifiable.”

In the spring of 2008, Tepco conducted a simulation and concluded that tsunami as high as 15.7 meters could hit the Fukushima plant. But the firm still did not take action before the 2011 disaster, instead saying the simulation was based on a hypothetical scenario and that there was no evidence suggesting such powerful tsunami would actually engulf the Tohoku region.

In its ruling on Sept. 22, Chiba District Court denied any central government responsibility but ordered Tepco — now Tokyo Electric Power Company Holdings Inc. — to pay additional compensation of ¥376 million to 42 evacuees. Both Tepco and the plaintiff have appealed to a higher court. ”

by Reiji Yoshida, The Japan Times

source

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

source

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

source