Japan’s nuclear energy choices — Kathleen Araujo, The Japan Times

Read Kathleen Araujo analysis of Japan’s energy policy. She is an assistant professor at Stony Brook University, specializing in national decision-making on energy-environmental systems, and science and technology policy. This article is copyrighted by The Diplomat and distributed by Tribune Content Agency. You can read the article via The Japan Times.

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Updated 8/24/2015: Volcano issues unaddressed in nuclear plant restart; Japan raises warning level on volcano 50 km from just-restarted nuclear plant — The Japan Times

Updated Aug. 24, 2015, The Japan Times:

” Japan has seen its first nuclear power reactor restart in more than two years despite persisting safety issues related to volcanic eruptions.

The No. 1 reactor at Kyushu Electric Power Co.’s Sendai nuclear power plant in Kagoshima Prefecture came back online on Tuesday.

But the utility has not designated a site for relocating nuclear fuel in the event of a massive volcanic eruption, claiming that warning signs would give Kepco enough time to prepare and transfer the fuel.

The utility and the Nuclear Regulation Authority have also decided there is little chance of a major volcanic eruption in the next several decades.

In the event of a major eruption, however, pyroclastic flows could reach the plant and disable cooling functions for its reactors and spent fuel, which could trigger massive radioactive emissions.

There are five major calderas around the Sendai plant, suggesting that massive eruptions have occurred there.

The plant currently stores 1,946 fuel assemblies in spent fuel pools. The sheer volume makes it hard to find a relocation site big enough to take them.

A panel of volcano experts advising the NRA has compiled a report indicating that there are currently no technologies that can precisely predict the timing and scale of a major eruption.

Toshitsugu Fujii, a member of the panel and chairman of the Meteorological Agency’s Coordinating Committee for Prediction of Volcanic Eruptions, has said that the panel’s opinion is not necessarily consistent with that of the NRA.

According to experts, the commonly held view is that it is impossible to predict a major eruption from warning signs because such eruptions occur only once every 10,000 years in Japan, so the data are scant.

The panel has proposed launching an advisory organization to the NRA to help deal with volcanic eruption forecasting. Due to time constraints, however, the launch of the organization is expected to be in September at the earliest.

The panel has also pointed out that the NRA should set standards for judgments on whether an impending eruption would be huge, but the time-line for setting such criteria is undecided.

Evacuation-plan worries

Two hospitals and 15 welfare facilities for elderly people within 10 km of the Sendai plant should have evacuation plans in the event that a serious nuclear accident occurs. However, concerns remain.

The prefectural government initially asked welfare facilities within 30 km of the plant to draw up evacuation plans in line with a central government policy. But it later changed course. Kagoshima Gov. Yuichiro Ito insisted that it would be enough if evacuation plans within 10 km are in place and that those beyond that would be unworkable.

The Otama-san no Ie elderly group home, the welfare facility closest to the nuclear plant — about 1 km south of the plant’s main gate — included an evacuation destination beyond 30 km of the plant and four routes to it in its plans.

“This is supplementary to local governments’ evacuation plans,” said Keiji Miyauchi, general manager of the group home.

Under the group home’s evacuation plans, residents will be first taken to a nearby shelter built by the Satsumasendai city government. The shelter, equipped with a filtered venting system that can block radioactive materials, has four days’ worth of water and food.

But Miyauchi said: “The group home has only a staff of two during the night shift. It would be difficult to take 18 elderly residents, some of whom are in wheelchairs, to the shelter.”

Miyauchi is also concerned about the evacuation routes. “Roads would be congested because they are narrow,” he said. “Some roads may be destroyed and made inaccessible if an earthquake occurs.”

Broad evacuation plans are available but details cannot be fixed, said an official at another elderly facility within 10 km of the nuclear plant. “Needs among elderly people change depending on the season,” the official said.

The facility has an evacuation agreement in place for an elderly home located beyond 30 km from the nuclear plant to accept its residents. But how to care for these evacuees remains uncertain.

“A facility alone can’t determine what to do after evacuations, and this is a matter that needs to be decided by the central or prefectural government,” the official said. ”

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Also read The Japan Times’ article, “Volcanic activity slows at Sakurajima but alert remains in force

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Posted Aug. 17, 2015, The Japan Times:

” The Meteorological Agency said Saturday that Mount Sakurajima in Kagoshima Prefecture, 50 km from a just-restarted nuclear plant, is showing signs of increased volcanic activity and that nearby residents should prepare to evacuate.

In line with the move, the Kagoshima municipal government issued an evacuation advisory to the residents of three districts on the island where the volcano is located.

Sakurajima is one of Japan’s most active volcanoes and erupts almost constantly. But a larger than usual eruption could be in the offing, an official at the weather agency said.

“There is the danger that stones could rain down on areas near the mountain’s base, so we are warning residents of those areas to be ready to evacuate if needed,” the official added.

The agency also said it had raised the warning level on the peak, 990 km southwest of Tokyo, to an unprecedented 4, for prepare to evacuate, from 3.

Japan on Tuesday restarted a reactor at the Sendai nuclear plant, some 50 km from Sakurajima. It is the first reactor to be restarted under new safety standards put in place after the 2011 Fukushima disaster.

Critics have long pointed out that the plant is also located near five giant calderas, crater-like depressions formed by past eruptions, with the closest one some 40 km away.

Still, the Nuclear Regulation Authority has said the chance of major volcanic activity during the life span of the Sendai plant is negligible.

Two years ago, Sakurajima shot ash some 5,000 meters into the air.

Japan lies on the “Ring of Fire” — a horseshoe-shaped band of fault lines and volcanoes around the edges of the Pacific Ocean — and is home to more than 100 active volcanoes.

Last year, Mount Ontake in central Japan erupted unexpectedly, killing 63, the worst volcanic disaster for nearly 90 years. In May, a remote island south of Kyushu was evacuated due to another eruption. ”

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*Japan’s natural perils, and promises, in the wake of Fukushima — Nassrine Azimi via The Asia-Pacific Journal: Japan Focus

” The first paragraph in the first volume of A History of Japan, by the scholarly British diplomat Sir George Sansom, is a detailed description of the islands’ geology.

Writing in 1958 of the country he so loved, with its “mighty volcanic convulsions”, Sir George depicts the physical drama of peaks soaring two miles above and plunging five miles below sea level, and wisely cautions that “so immense a range of elevation within short lateral distances develops such stresses that this part of the earth’s crust is a highly unstable area….”

The Japan Landslide Society simply calls this archipelago the “Scar-Laden Islands.”

In August this year we witnessed at close range just how scar-laden: massive rains and landslides brought down entire mountaintops in many suburbs of Hiroshima, killing scores. The tragedy could well happen in other parts of the country.

Then on September 27th the sacred, unpredictable Mount Ontake erupted suddenly, trapping hundreds of climbers out to admire its famed autumn foliage. The eruption prompted a massive and dangerous rescue operation by thousands of firefighters, police and Self-Defense Forces members. Still, at least 60 people are reported dead.

In the aftermath of the eruption, the government promptly called for renewed efforts at monitoring volcanic activity. Yet Mount Ontake, listed as one of the country’s 110 active volcanos, was already under close scrutiny by the Meteorological Agency; intensifying tremors–85 on September 11 alone–had been registered but not deemed threatening.

In technology-overloaded Japan, monitoring hardly seems the problem.

Rather, volcanic eruptions–and other natural disasters–in a land perched on the edge of the Ring of Fire and straddling four tectonic plates should be considered the norm. And some scientists now worry that the magnitude 9 earthquake of March 11, 2011 may well intensify risks–this July a French geophysicist and his team released a study suggesting pressure is building on Mount Fuji, also an active volcano.

Last week the three prefectures at the foot of Mount Fuji conducted eruption drills, sobered by the experience of how ash from the Mount Ontake eruption had completely disrupted rescue operations. Similarly, earlier this month, the respected volcanologist Fujii Toshitsugu, professor emeritus at the University of Tokyo and head of a government-commissioned panel, challenged assumptions that the Sendai reactors in Kyushu, first in-line in the government’s schedule to reactivate dormant nuclear plants, were immune to volcanic eruptions. He suggested that heavy ash from the eruption of Mount Sakurajima — only 40 kilometers from the plant — could make reaching the plant and basic evacuation protocols quite impossible.

If natural disasters are simply unavoidable, then for a country smaller than the state of California and with more than three times the population, the presence of nuclear power plants seems, to say the least, a little akin to playing Russian roulette.

During recent Diet debates, Obuchi Yuko, then minister of economy, trade and industry and till two weeks ago an upcoming star of the ruling Liberal Democratic Party, insisted that in its push to restart nuclear plants the government was adamant about ensuring the strictest safety measures, stating that such standards were similar to those of France and other advanced nations.

The comparison to France, often made, is hardly apt: France is not perennially threatened by massive earthquakes, tsunamis or volcanic eruptions, nor is it on the path of mega typhoons (like the two which battered us just this month). In the past year, alone, Japan has had hundreds of small earthquakes, while France has had five. Japan is also two-thirds smaller than France, with almost double the population. The risk factors, when it comes to nuclear power plants, are fundamentally different.

In late September, a group of us from Hiroshima returned to Fukushima, to see for ourselves how rebuilding was progressing. Of the three prefectures which took the brunt of the earthquake and tsunami in 2011 Fukushima, with the decommissioned yet still precarious No. 1 (Daiichi) nuclear power plant, is the one still gripped by deep uncertainty, even if both Miyagi and Iwate suffered greater human losses from the tsunami (by a factor of five in Miyagi): they have mourned, grieved, collected huge piles of tsunamis debris and are now pressing ahead with reconstruction plans.

Not Fukushima. Large swaths of the prefecture remain unsettled. Within the nuclear plant’s 20-kilometer exclusion zone most towns are empty. As we drove through the eerily silent streets of those closest to the battered plant, Tashiro Akira, a veteran investigative reporter who has written extensively on nuclear accidents, gave us rough estimates of their pre-disaster populations–and of their current status: Namie (22,000, now semi-restricted), Futaba (7,400, still abandoned), Okuma (11,515, still abandoned), Tomioka (15,800, still abandoned), Naraha (8200, now semi-restricted).

The quick money that had been flowing from TEPCO to these communities in the past decades does not seem to have left much in terms of quality buildings or a decent urban environment. But an abandoned city is nonetheless a mournful sight: curtains still in place, kitchen-ware glimpsed through a window, children’s bicycles parked outside empty homes.

In Minami Soma we visited the Farm Sanctuary, 14 kilometers from the beleaguered power plant, where an irreverent cattle farmer by the name of Yoshizawa Masami has chosen to defy authorities and remain with his animals. Called Kibo no Bokujyo (Ranch of Hope) in Japanese, it also offers a place for other farmers who have had to abandon their lands but do not know what to do with their contaminated animals. The Farm Sanctuary has become a sort of unofficial test site, to monitor the effects of radiation on animals.

But even more distant towns, like Iitate, remain in limbo. Some 45 kilometers from the plant, Iitate was initially designated a safe haven before it, too, was found to be a radioactive hotspot. Its 6000 inhabitants have now either left or can only come in during day-time hours. A superbly-built nursing home for the elderly now caters to the few remaining residents – average age 87 – who were simply too old to move. Room after room is empty – it is impossible to find staff willing or able to live and work in Iitate.

A farming and ranching community before the nuclear disaster, the only people we did see at work in Iitate were some of 3000 contract workers, whose job is to remove contaminated topsoil — part of the government’s complex and questionable decontamination policy. The topsoil, alongside leaves and other plant material, is then stuffed into thousands of black plastic containers, now scattered across the landscape. Naturally no region is willing to accept the dreaded material, despite pressures and monetary cajoling by the central government. The cleanup, which was meant to be completed this March, has just been extended by another two years.

As we viewed the landscape, the idea that Iitate and other cities affected by the nuclear accident could soon return to business as usual — through diligent scrubbing of roofs and removal of topsoil — seemed far-fetched indeed: like the rest of Fukushima Iitate is covered with mountains and forests, exposed to natural elements. In her thoughtful and meticulously researched article entitled ‘Touching the Grass: Science, Uncertainty and Everyday life from Chernobyl to Fukushima’[1] Tessa Morris-Suzuki points to research on the topsoil removal, which can temporarily lower radiation levels, but the effects of which are dubious as ‘radiation accumulated in leaf litter in the mountain forests is constantly washed down into farm fields by the flow of water, raising the levels of radioactivity again.’

Years (and billions of yen) could well be spent shifting topsoil, but would any young family be willing to raise kids there?

Dr. Kurokawa Kiyoshi, chairman of the Nuclear Accident Independent Investigative Committee has famously, and succinctly, quipped of the government’s cleanup effort: “Water keeps building up inside the plant, and debris keeps piling up outside of it. This is all just one big shell game aimed at pushing off the problems until the future.”[2]

Yet admitting the complexities raises fundamental problems for authorities, from the practical –i.e. compensation and relocation issues — to the deeply ethical: if one single nuclear accident is proving so debilitating, how then, in the face of deep popular opposition, to justify bringing the country’s dormant plants on-line, as the Abe government wishes to do? And if even Japan, a technology giant, is to put the nail to the coffin of its own towns in the aftermath of a nuclear accident, how to justify its planned exports to other nations?

So Fukushima’s residents linger in uncertainty. The elderly, with less to fear of radiation’s long-term effects, are resigned to return home; not those with young children. Many men, for the sake of jobs, would return but women, more concerned about their family’s health, would not. The pressure on every family is huge. The new term genpatsu rikon (atomic divorce) captures the personal tragedies.

Morris-Suzuki highlights the difficulty, heightened in the Internet age, for ordinary people to live with the kind of insidious uncertainty that has become the hallmark of environmental, and especially nuclear, pollution. As night fell, we had to leave Iitate in time for the curfew that bans people from entering the area beyond certain hours. Driving down the mountain and past one dark, abandoned house after another, I better understood how tired the citizens of Fukushima were of the flow of visiting and pontificating delegates — scientists and central authorities, singers, actors, upcoming politicians, idealistic students, well-intentioned foreigners… At the end of the day, however, we all left.

Hence a certain listlessness in Fukushima, that seems to afflict everyone and, contrary to most places, the young in particular. The welcoming and valiant senior staff at the fisheries association we visited near Iwaki City seemed reassured by their brand new machines sent to test radiation levels of incoming fish every week; the younger staff admitted readily that manning the complicated machinery was at times quite beyond their competence. In Koriyama, one of Fukushima Prefecture’s three largest cities, the senior architect I interviewed expressed hope that large-scale building plans would restart soon. His younger colleague, father of young children, sat stone-faced, looking more doubtful.

There are those who point at Hiroshima and Nagasaki as the ‘reassuring’ story, of the possibility of revival after nuclear catastrophe. This is to forget the price paid and the discriminations faced by the survivors and at least two generations of Hiroshima and Nagasaki citizens. It is also to forget the differences between 1945 and 2011: there were no hand-held Geiger counters in every household then, no Internet to spread news of contaminated soil, fish, water or hotspots. Fukushima Prefecture was a prime food producer in Japan before the accident: when or even whether it shall retrieve that label again, in a globalized world where reputations are so easily made or broken, is an open question.

Still, by now Prime Minister Abe may have little political capital to lose on account of the physically close yet psychologically distant Fukushima. But as Andrew DeWit of Tokyo’s Rikkyo University and an astute observer of Japanese energy policies has written in the Asia-Pacific Journal (http://japanfocus.org/-Andrew-DeWit/4174), the government’s reluctance to declare a stark and clear commitment to renewables (and to the eventual closure of nuclear plants), is a significant opportunity loss.

Japan, DeWit writes, is hardly the “resource-poor” country pro-nuclear politicians so love to invoke. In terms of renewables, it sits among top contenders, with abundant thermal energy sources — the bright side of being so disaster-prone. It is “blessed” with powerful winds and typhoons, waves, volcanoes, vast forests (68 percent of the land), torrential rivers and summers of scorching, ever-present sun.

Naysayers point to the challenges facing Germany, which after decades of an intense national debate, took the message of the Fukushima nuclear accident to heart and did what everyone had expected Japan to do: bring its reliance on nuclear energy to an end. Yes, Germany now struggles with its carbon emissions, but these will decline with time while the advantages — including job creation – of Germany’s shift to green energy are already starting to outweigh the minuses.[3] The question to ask is rather what advantages could Japan have reaped, had its political leaders, even in the last few years, been half as ‘green‘ as their German counterparts? It is enough to note how absent is anything close to a Green Party in mainstream Japanese politics to understand the obstacles to a fullscale commitment to green energy strategies in the wake of the Fukushima nuclear accident.

There are nevertheless bright spots to be found in a number of localities. The architect Ito Toyo — winner of last year’s Pritzker prize and an intelligent and compelling voice for the reconstruction of the Tohoku region after the March 2011 disasters — has led experimental reconstruction projects in the affected areas. Ito has written of the need to question, as architects but even more as human beings what to do henceforth, of the need to ‘go back to square one and reexamine the essential meaning of architecture.’[4] The same shift in thinking must apply to all of us, in particular the ‘experts’.

Poll after poll have shown a steady majority of the Japanese far more willing than their politicians to embrace renewables and the “fifth fuel”, conservation, rather than return to nuclear power. Given Japan’s technological strengths, with the right leadership, policies and technologies, a shift is ultimately possible. However well-packaged, nuclear accident cleanup just remains too difficult — devouring massive time, money and energy, and none can ascertain that it works.

From time immemorial, Japan’s greatest perils and privileges have come from Nature. This remains unchanged – or rather has become even more compelling – in the early 21st century. Ancient rites and rituals, seemingly arcane or irrelevant to challenges of our modern age, are but reminders of this immutable reality. Last year the Grand Shrine of Ise, the country’s most sacred sanctuary, held its Sengu — renewal — ceremony, conducted since 690 AD at 20-year intervals. The rite has immensely practical value: the intricate architecture and carpentry of the structures, for example, demands intense and regular transmission of elaborate building techniques from generation to generation; the massive timbers require upkeep of designated forests and watersheds, and the special food offerings impose careful cultivation of nearby rice paddies, nurturing of fruit groves, care of fishing and gaming areas, the consistent sharing of knowledge about the land’s ecology. They also bring, century after century, not just spiritual well-being but enormous revenues to Mie Prefecture.

Location. Location. Location. George Sansom was right, to start his history of Japan with geology. Or as my late father would constantly remind us: ‘Never, ever, forget your geography’. ”

source to Nassrine Azimi’s article with internal references and photographs

Colossal volcanic eruption could destroy Japan at any time: study — The Japan Times; Japan warns of increased activity at volcano near nuclear plant — Reuters

Updated Oct. 27, 2014, The Japan Times: ” Japan could be nearly destroyed by a volcanic eruption over the next century that would put nearly all of its population of 127 million people at risk, a new study says.

“It is not an overstatement to say that a colossal volcanic eruption would leave Japan extinct as a country,” Kobe University earth sciences professor Yoshiyuki Tatsumi and associate professor Keiko Suzuki said in the study, released publicly on Wednesday.

The experts said they analyzed the scale and frequency of volcanic eruptions throughout the archipelago over the past 120,000 years and calculated that the odds of a devastating eruption at about 1 percent over the next 100 years.

The chance of a major temblor striking Kobe within 30 years was estimated at about 1 percent just a day before a 7.2-magnitude quake struck the port city in 1995, killing 6,400 people and injuring nearly 4,400 others, the study noted.

“Therefore, it would be no surprise if such a colossal eruption occurs at any moment,” it added.

The Kobe University researchers said their study is critical because Japan is home to about 7 percent of the volcanoes that have erupted over the past 10,000 years.

A disaster on Kyushu, which has been struck by seven massive eruptions over the past 120,000 years, would see an area with 7 million people buried by flows of lava and molten rock in just two hours, they said.

Volcanic ash would also be carried by westerly winds toward the main island of Honshu, making nearly the entire country “unlivable” as it strangled infrastructure, including key transport systems, they said.

It would be “hopeless” trying to save about 120 million living in major cities and towns across Honshu, the study said.

The study called for new technology to more accurately grasp the state of the “magma reservoirs” that are spread across the Earth’s crust in layers a few kilometers deep. ”

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Posted Oct. 24, 2014: ” (Reuters) – Japan warned on Friday that a volcano in southern Japan located roughly 64 km (40 miles) from a nuclear plant was showing signs of increased activity that could possibly lead to a small-scale eruption and warned people to stay away from the summit.

The warning comes nearly a month after another volcano, Mt Ontake, erupted suddenly when crowded with hikers, killing 57 people in Japan’s worst volcanic disaster in nearly 90 years.

Ioyama, a mountain on the southwestern island of Kyushu, has been shaken by small tremors and other signs of rising volcanic activity recently, including a tremor lasting as long as seven minutes, an official at the Japan Meteorological Agency’s volcano division said.

“There is an increase in activity that under certain circumstances could even lead to a small scale eruption, but it is not in danger of an imminent, major eruption,” the official said.

The warning level on the mountain has been raised from the lowest possible level, normal, to the second lowest, which means that the area around the crater is dangerous, he added.

Ioyama lies in the volcanically active Kirishima mountain range and is roughly 64 km from the Sendai nuclear plant run by Kyushu Electric Power Co, which the Japanese government wants to restart even though the public remains opposed to nuclear power following the Fukushima crisis.

Critics point out that the Sendai plant is located about 50 kms (31 miles) from Mount Sakurajima, an active volcano that erupts frequently. Five giant calderas, crater-like depressions formed by past eruptions, are also in the region, the closest one 40 kms (25 miles) away.

The plant still needs to pass operational safety checks as well as gain the approval of local authorities and may not restart till next year.

Before giving its initial greenlight to restart the plant in July, the Nuclear Regulation Authority (NRA) said the chance of major volcanic activity during the lifespan of the Sendai nuclear plant was negligible.

On Friday, the warning level for the Sakurajima volcano, which erupts frequently, was at 3, which means that people should not approach the peak.

Japan lies on the “Ring of Fire” – a horseshoe-shaped band of fault lines and volcanoes around the edges of the Pacific Ocean – and is home to more than 100 active volcanoes.

Experts warn that the mammoth 9.0 March 2011 quake may have increased the risk of volcanic activity throughout Japan, including that of iconic Mount Fuji. ”

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Japan reactor near active volcanos called unsafe — Associated Press via ABC News

” A prominent volcanologist disputed Japanese regulators’ conclusion that two nuclear reactors were safe from a volcanic eruption in the next few decades, saying Friday that such a prediction was impossible.

A cauldron eruption at one of several volcanos surrounding the Sendai nuclear power plant in southern Japan could not only hit the reactors but could cause a nationwide disaster, said Toshitsugu Fujii, University of Tokyo professor emeritus who heads a government-commissioned panel on volcanic eruption prediction.

Nuclear regulators last month said two Sendai reactors fulfilled tougher safety requirements set after the 2011 Fukushima disaster. The regulators ruled out a major eruption over the next 30 years until the reactors’ reach the end of their usable lifespan.

A surprise eruption of Mount Ontake in central Japan on Sept. 27 has renewed concerns about the volcanos in the region.

“It is simply impossible to predict an eruption over the next 30 to 40 years,” Fujii said. “The level of predictability is extremely limited.”

He said at best an eruption can be predicted only a matter of hours or days.

Studies have shown that pyroclastic flow from an eruption 90,000 years ago at one of the volcanos near the Sendai plant in Kagoshima prefecture reached as far as 145 kilometers (90 miles) away, Fujii said. He said a pyroclastic flow from Mount Sakurajima, an active volcano that is part of the larger Aira Cauldron, could easily hit the nuclear plant, which is only 40 kilometers (25 miles) away.

Heavy ash falling from an eruption would make it impossible to reach the plant, and could also affect many parts of the country including Tokyo, he said. Many nuclear power plants could be affected in western Japan, 1,000 kilometers (620 miles) southwest of the capital.

The two Sendai reactors are the first ones approved under the new safety requirement, which added resistance to volcanic eruption as part of safety evaluation. Prime Minister Shinzo Abe is pushing to restart the two, and any of the country’s 46 other workable reactors that are deemed safe, saying nuclear power is stable and relatively cheap compared to other energy source and key to Japan’s economic recovery.

Kyushu Electric Power Co., which operates the Sendai plant, promised taking measures to ensure access to workers in case of ash falls of up to 15 centimeters (6 inches), while installing a monitoring system to detect changes to volcanic activities. The utility also promised to transfer fuel rods to safer areas ahead of time if signs of eruptions are detected — a time-consuming process that experts say is unrealistic.

Fujii said ash falling as thick as 10 centimeters (4 inches) would make any vehicle, except for tanks, virtually inoperable. Power lines would be severed due to the weight of ash on them, causing blackouts and possibly cutting off electricity to the reactor cooling system.

Only after approving the reactors’ safety, the regulatory authority established a volcano panel to discuss the impact of eruptions and countermeasures. Fujii, a member of that panel, said experts are opposed to the regulators’ views. Even though catastrophic eruption could occur only once in as many as 10,000 years, a likelihood of one cannot be ruled out either, he said.

“Scientifically, they’re not safe,” he said of the Sendai reactors. “If they still need to be restarted despite uncertainties and risks that remain, it’s for political reasons, not because they’re safe, and you should be honest about that.” ”

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