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

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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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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

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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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Fears of another Fukushima as Tepco plans to restart world’s biggest nuclear plant — The Guardian

” If a single structure can define a community, for the 90,000 residents of Kashiwazaki town and the neighbouring village of Kariwa, it is the sprawling nuclear power plant that has dominated the coastal landscape for more than 40 years.

When all seven of its reactors are in operation, Kashiwazaki-kariwa generates 8.2m kilowatts of electricity – enough to power 16m households. Occupying 4.2 sq km of land along the Japan Sea coast, it is the biggest nuclear power plant in the world.

But today, the reactors at Kashiwazaki-kariwa are idle. The plant in Niigata prefecture, about 140 miles (225km) north-west of the capital, is the nuclear industry’s highest-profile casualty of the nationwide atomic shutdown that followed the March 2011 triple meltdown at Fukushima Daiichi.

The company at the centre of the disaster has encountered anger over its failure to prevent the catastrophe, its treatment of tens of thousands of evacuated residents and its haphazard attempts to clean up its atomic mess.

Now, the same utility, Tokyo Electric Power [Tepco], is attempting to banish its Fukushima demons with a push to restart two reactors at Kashiwazaki-kariwa, one of its three nuclear plants. Only then, it says, can it generate the profits it needs to fund the decommissioning of Fukushima Daiichi and win back the public trust it lost in the wake of the meltdown.

This week, Japan’s nuclear regulation authority gave its formal approval for Tepco to restart the Kashiwazaki-kariwa’s No. 6 and 7 reactors – the same type of boiling-water reactors that suffered meltdowns at Fukushima Daiichi.

After a month of public hearings, the nuclear regulation authority concluded that Tepco was fit to run a nuclear power plant and said the two reactors met the stricter safety standards introduced after the 2011 disaster.

Just before that decision, Tepco gave the Guardian an exclusive tour of what it claims will be the safest nuclear plant in the world.

Now, as on the day of the triple disaster that brought widespread destruction to Japan’s northeast coast, Kashiwazaki-kariwa has the look of a working nuclear plant. Just over 1,000 Tepco staff and 5,000-6,000 contract workers provide the manpower behind a post-Fukushima safety retrofit that is projected to cost 680 billion yen ($6.1bn).

They have built a 15-metre-high seawall that, according to Tepco, can withstand the biggest tsunami waves. In the event of a meltdown, special vents would keep 99.9% of released radioactive particles out of the atmosphere, and corium shields would block molten fuel from breaching the reactors’ primary containment vessels. Autocatalytic recombiners have been installed to prevent a repeat of the hydrogen explosions that rocked four of Fukushima Daiichi’s reactors.

Other parts of the sprawling complex are home to fleets of emergency vehicles, water cannon, back-up power generators, and a hilltop reservoir whose 20,000 tonnes of water will be drawn to cool reactors in the event of a catastrophic meltdown.

“As the operator responsible for the Fukushima accident, we’re committed to learning lessons, revisiting what went wrong and implementing what we learned here at Kashiwazaki-kariwa, says the plant’s chief, Chikashi Shitara. “We are always looking at ways to improve safety.

“Because of our experience at Fukushima, we’re committed to not making the same mistakes again – to make the safety regime even stronger. That’s what we have to explain to members of the public.”

‘This is no place for a nuclear power plant’

The public, however, is far from convinced. Last year, the people of Niigata prefecture registered their opposition to the utility’s plans by electing Ryuichi Yoneyama, an anti-nuclear candidate, as governor. Exit polls showed that 73% of voters opposed restarting the plant, with just 27% in favor.

Yoneyama has said that he won’t make a decision on the restarts, scheduled for spring 2019, until a newly formed committee has completed its report into the causes and consequences of the Fukushima disaster – a process that could take at least three years.

For many residents, the plant’s location renders expensive safety improvements irrelevant. “Geologically speaking, this is no place for a nuclear power plant,” says Kazuyuki Takemoto, a retired local councillor and a lifelong anti-nuclear activist.

Takemoto cites instability caused by the presence of underground oil and gas deposits in the area, and evidence that the ground on which Tepco’s seawall stands is prone to liquefaction in the event of a major earthquake.

Local critics have pointed to the chaos that could result from attempting to evacuate the 420,000 people who live within a 30km radius of Kashiwazaki-kariwa. “That’s more people than lived near Fukushima, plus we get very heavy snowfall here, which would make evacuating everyone impossible,” Takemoto adds. “The situation would be far worse than it was in Fukushima.”

Adding to their concerns are the presence of seismic faults in and around the site, which sustained minor damage during a magnitude-6.6 offshore earthquake in 2007. Two active faults – defined by nuclear regulators as one that has moved any time within the last 400,000 years – run beneath reactor No. 1.

But for Tepco, a return to nuclear power generation is a matter of financial necessity, with the utility standing to gain up to ¥200 billion in annual profits by restarting the two reactors at Kashiwazaki-Kariwa.

The bill for decommissioning Fukushima Daiichi, decontaminating neighbourhoods and compensating residents affected by the meltdown could reach 21.5tr yen [$191bn], according to government estimates. That is on top of the money the firm is spending on importing expensive fossil fuels to fill the vacuum left by the nuclear shutdown.

Earlier this year, the Japan Centre for Economic Research said the total cost of the four-decade Fukushima cleanup – including the disposal of radioactive waste from the plant’s three damaged reactors – could soar to between 50-70tr yen.

“As Tepco’s president and our general business plan have made clear, restarting the reactors here is very important to us as a company,” says Shitara.

Much is at stake, too, for Japan’s prime minister, Shinzo Abe, who has put an ambitious return to nuclear power generation at the centre of his energy policy. His government wants nuclear to provide about 20 percent Japan’s electricity by 2030 – a move that would require the restart of about 30 reactors.

Of the country’s 48 operable reactors, only four are currently online. Several others have passed stringent new safety tests introduced in the wake of Fukushima, but restarts have encountered strong local opposition.

As part of the restart process, people across Japan were recently invited to submit their opinions on the Kashiwazaki-kariwa restart and Tepco’s suitability as a nuclear operator.

Kiyoto Ishikawa, from the plant’s public relations department, insists Tepco has learned the lessons of Fukushima. “Before 3-11 we were arrogant and had stopped improving safety,” he said. “The earthquake was a wake-up call. We now know that improving safety is a continuous process.”

The firm’s assurances were dismissed by Yukiko Kondo, a Kariwa resident, who said the loss of state subsidies if the plant were to remain permanently idle was a sacrifice worth making if it meant giving local people peace of mind.

“Tepco caused the 2011 accident, so there is no way I would ever support restarting nuclear reactors here,” she said. “They kept telling us that Fukushima Daiichi was perfectly safe – and look what happened.” ”

by Justin McCurry, The Guardian

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