‘Yoshida’s Dilemma: One Man’s Struggle to Avert Nuclear Catastrophe’: But for him, Fukushima could have been much worse — The Japan Times

” Disaster response, even at its most heroic, can fall to people who would rather be somewhere else.

So it was for Masao Yoshida, who, while helming the Fukushima No. 1 nuclear power plant during the disaster in 2011, gave the groan, “Why does this happen on my shift?”

But in some ways Yoshida, an industry veteran of 32 years, was the right man to handle the crisis. His leadership during those days on the edge, at times in defiance of orders from the top of the utility that employed him, is at the center of Rob Gilhooly’s new book “Yoshida’s Dilemma: One Man’s Struggle to Avert Nuclear Catastrophe.”

Gilhooly writes from the eye of the storm, putting the reader in the plant’s control room with almost claustrophobic immediacy. One of his challenges was to render the emergency in real-time. How much can prose, moving forward in measured steps, convey a lethal technology unraveling in extremis? How do you convey the breakdown of machinery without getting mired in technical detail?

“It was difficult,” says Gilhooly, who spent almost four years researching and writing the book. “What struck me about the plant workers — it sounded like complete chaos. My decision was not to make it sound orderly. I wanted it to appear chaotic, without the writing becoming chaotic itself. I tore my hair out over the technical details, because I wanted the book to be readable.”

In the end, the book is a cumulative experience — an intense ride that rewards endurance. Gilhooly weaves in the history of nuclear energy in Japan, interviews with experts and re-created conversations among the plant workers.

“Yoshida was a straight talker from Osaka — a larger-than-life personality,” says Gilhooly, who interviewed the superintendent off the record. “He was different from the other superintendents, more prepared to stick his neck out. He was sharper, more bloody-minded. When tipping his hat to authority, he may have done so with a quietly raised middle finger.”

This attitude might have saved lives, when, after a hydrogen blast at the No. 1 plant, Tepco HQ in Tokyo ordered staff to evacuate. Yoshida knew that the executives had little idea of what was actually happening at the plant. Going behind the backs of his superiors, he contacted then-Prime Minister Naoto Kan, insisting that leaving the plant would be reckless. The utility also ordered that seawater not be pumped through the reactor as coolant, since that would render it useless for energy generation in the future. Exposed to life-threatening levels of radiation, Yoshida and his team defied the order, scrambling to cool the overheating reactor with seawater.

The desperate move worked. The team managed to cool the reactor, and later the Fukushima Nuclear Accident Independent Investigation Commission, which was authorized by the Diet, concluded in its report that “(Yoshida’s) disregard for corporate instructions was possibly the only reason that the reactor cores didn’t explode.”

In Western media coverage of the Fukushima disaster, much was made of Japanese groupthink. A culturally ingrained obedience and a reluctance to question authority was blamed in part for the disaster. Still, the responses vary, and some staff put safety concerns over company loyalty.

“I didn’t want to editorialize,” says Gilhooly, who writes with a calm, thoughtful voice, avoiding the temptation of melodrama. “But yes, Yoshida — and others — refuted the stereotype that was used to explain parts of the disaster.”

Gilhooly is talking to a Japanese publisher, but thinks a translated version may prove difficult: His sources spoke freely about the events at the plant assuming the interviews wouldn’t be published in Japanese. Still, Gilhooly, who takes a stand in the book against using nuclear energy, hopes to fuel the ongoing debate in his adopted home.

“I just wanted to know the truth,” he says. “There is a discussion that needs to happen about nuclear power — about disaster un-preparedness in Japan. I wanted to contribute to that argument. It’s six years on and already we are airbrushing some things out.”

The book points out the gulf between rural Fukushima and the large cities consuming the energy it produced. Gilhooly talked to Atsufumi Yoshizawa, Yoshida’s deputy at the plant, who recalled the first home leave with his boss, a month after the disaster:

“Tokyo was … as though nothing had happened. They were selling things as usual, women were walking around with high heels and makeup as usual, while we didn’t even have our own clothes (which had been contaminated). I remember thinking, ‘What the hell is this? How can it be so different?’ I realized just how useless it would be to try and explain the situation at the plant to these people, what we had been through and the fear we had faced.”

It is a punch in the gut, then, to read about Yoshida’s death from esophageal cancer at age 58, just two years after his exposure to radiation. It’s one of the many elements of the Fukushima crisis that stirs anger, demanding a change that honors the lessons and sacrifice.

Gilhooly points out that, unlike Yoshida in the stricken plant, Japan has the chance to make positive choices about the future, choices that should be informed by the suffering in Fukushima.

“We should think more about how we use energy,” he concludes. “There are things we can do better, with small changes in lifestyle.” ”

by Nicolas Gattig, The Japan Times

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Near miss at Fukushima is a warning for U.S., panel says — Richard Stone, Science

” Japan’s chief cabinet secretary called it “the devil’s scenario.” Two weeks after the 11 March 2011 earthquake and tsunami devastated the Fukushima Daiichi Nuclear Power Plant, causing three nuclear reactors to melt down and release radioactive plumes, officials were bracing for even worse. They feared that spent fuel stored in the reactor halls would catch fire and send radioactive smoke across a much wider swath of eastern Japan, including Tokyo.

Thanks to a lucky break detailed in a report released today by the U.S. National Academies, Japan dodged that bullet. The near calamity “should serve as a wake-up call for the industry,” says Joseph Shepherd, a mechanical engineer at the California Institute of Technology in Pasadena who chaired the academy committee that produced the report. Spent fuel accumulating at U.S. nuclear reactor plants is also vulnerable, the report warns. A major spent fuel fire at a U.S. nuclear plant “could dwarf the horrific consequences of the Fukushima accident,” says Edwin Lyman, a physicist at the Union of Concerned Scientists, a nonprofit in Washington, D.C., who was not on the panel.

After spent fuel is removed from a reactor core, the fission products continue to decay radioactively, generating heat. Many nuclear plants, like Fukushima, store the fuel onsite at the bottom of deep pools for at least 5 years while it slowly cools. It is seriously vulnerable there, as the Fukushima accident demonstrated, and so the academy panel recommends that the U.S. Nuclear Regulatory Commission (NRC) and nuclear plant operators beef up systems for monitoring the pools and topping up water levels in case a facility is damaged. It also calls for more robust security measures after a disaster. “Disruptions create opportunities for malevolent acts,” Shepherd says.

At Fukushima, the earthquake and tsunami cut power to pumps that circulated coolant through the reactor cores and cooled water in the spent fuel pools. The pump failure led to the core meltdowns. In the pools, found in all six of Fukushima’s reactor halls, radioactive decay gradually heated the water. Of preeminent concern were the pools in reactor Units 1 through 4: Those buildings had sustained heavy damage on 11 March and in subsequent days, when explosions occurred in Units 1, 3, and 4.

The “devil’s scenario” nearly played out in Unit 4, where the reactor was shut down for maintenance. The entire reactor core—all 548 assemblies—was in the spent fuel pool, and was hotter than fuel in the other pools. When an explosion blew off Unit 4’s roof on 15 March, plant operators assumed the cause was hydrogen—and they feared it had come from fuel in the pool that had been exposed to air. They could not confirm that, because the blast had destroyed instrumentation for monitoring the pool. (Tokyo Electric Power Company, the plant operator, later suggested that the hydrogen that had exploded had come not from exposed spent fuel but from the melted reactor core in the adjacent Unit 3.) But the possibility that the fuel had been exposed was plausible and alarming enough for then-NRC Chairman Gregory Jaczko on 16 March to urge more extensive evacuations than the Japanese government had advised—beyond a 20-kilometer radius from the plant.

Later that day, however, concerns abated after a helicopter overflight captured video of sunlight glinting off water in the spent fuel pool. In fact, the crisis was worsening: The pool’s water was boiling away because of the hot fuel. As the level fell perilously close to the top of the fuel assemblies, something “fortuitous” happened, Shepherd says. As part of routine maintenance, workers had flooded Unit 4’s reactor well, where the core normally sits. Separating the well and the spent fuel pool is a gate through which fuel assemblies are transferred. The gate allowed water from the reactor well to leak into the spent fuel pool, partially refilling it. Without that leakage, the academy panel’s own modeling predicted that the tops of the fuel assemblies would have been exposed by early April; as the water continued to evaporate, the odds of the assemblies’ zirconium cladding catching fire would have skyrocketed. Only good fortune and makeshift measures to pump or spray water into all the spent fuel pools averted that disaster, the academy panel notes.

At U.S. nuclear plants, spent fuel is equally vulnerable. It is for the most part densely packed in pools, heightening the fire risk if cooling systems were to fail. NRC has estimated that a major fire in a U.S. spent fuel pool would displace, on average, 3.4 million people from an area larger than New Jersey. “We’re talking about trillion-dollar consequences,” says panelist Frank von Hippel, a nuclear security expert at Princeton University.

Besides developing better systems for monitoring the pools, the panel recommends that NRC take another look at the benefits of moving spent fuel to other storage as quickly as possible. Spent fuel can be shifted to concrete containers called dry casks as soon as it cools sufficiently, and the academy panel recommends that NRC “assess the risks and potential benefits of expedited transfer.” A wholesale transfer to dry casks at U.S. plants would cost roughly $4 billion. ”

by Richard Stone, Science

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Salt in the wound — Arnie Gundersen, Fairewinds Energy Education

” What really happened to the Fukushima Daiichi reactors when workers from owner Tokyo Electric Power Company added ocean saltwater to cool them?

Fairewinds recently received this question and important technical comments from several viewers and engineers regarding utility owner TEPCO’s use of saltwater to cool the Fukushima Daiichi atomic reactors during their triple meltdowns. As we continue looking at aging operating atomic reactors around the world, it is important to understand this issue and know what may go wrong at other sites.

Listen as Fairewinds’ Chief Engineer Arnie Gundersen explains why TEPCO’s workers injected saltwater into Fukushima’s failing reactors, what happens when salt water meets steel, and what forces come into play after saltwater is used to cool down an atomic reactor in this Fairewinds Audio Update. ”

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Melting of key parts blamed for Fukushima meltdown — NHK World

” The operator of the Fukushima Daiichi power plant says excessive heat from nuclear fuel at one of its damaged reactors may have caused some key parts to melt.

Officials at Tokyo Electric Power Company believe the loss of those components made it difficult to stop the Number 2 reactor from melting down and spewing out large amounts of radioactive substances following the March 2011 accident.

Four days after the onset of the accident, the emergency cooling system at the reactor stopped working.

In an attempt to cool fuel inside the reactor, the workers had no choice but to pour in water from a fire engine.

But they were unable to inject water as planned because of the high pressure that had built up inside the reactor.

The officials also could not use safety relief valves to release pressure. Those valves were designed to open when hit by high-pressure gas from a tank.

The TEPCO analysis determined that key parts of the gas feeding system may have melted, leading to a gas leak. The analysis says the temperature inside the reactor exceeded 200 degrees Celsius, far beyond the limit of the parts’ durability.

Those parts are present in all other reactors in the model line used at the Fukushima Daiichi plant. The utility plans to replace the parts at its other nuclear power plant in central Japan with heat-resistant ones. ”

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Defamation suit against Abe over Fukushima crisis thrown out: Court — Channel NewsAsia

” TOKYO: A Japanese court on Thursday threw out a defamation suit against Prime Minister Shinzo Abe by former premier Naoto Kan, who complained Abe published false claims about Kan’s handling of the Fukushima nuclear crisis.

Kan, prime minister at the time of the 2011 disaster, accused Abe of publishing untrue allegations that Kan had ordered plant operator Tokyo Electric Power (TEPCO) to stop pouring seawater onto overheating reactors to cool them and prevent a catastrophe.

The former premier sued Abe, an opposition lawmaker at the time of the crisis, for defamation in 2013.

Kan’s suit alleged that Abe made the claims in his e-magazine two months after the nuclear accident.

The March 11, 2011, quake-tsunami disaster triggered a meltdown at the nuclear power plant, the worst atomic accident since Chernobyl.

Kan, who resigned as prime minister later in 2011, had demanded that Abe apologise and pay ¥11 million (US$89,000) in damages.

A spokesman at the Tokyo District Court told AFP Thursday the lawsuit was “dismissed”, but declined to elaborate further.

In his ruling, presiding judge Norio Nagaya said that what Abe wrote was “within the arena of opinion and commentary”, according to Jiji Press.

Kan faced significant criticism at the time of the accident over his clumsy handling of the crisis, but did not issue such an order to TEPCO.

In the chaos immediately after the crisis, TEPCO executives — not Kan — told the head of the Fukushima Daiichi nuclear power plant to stop using seawater to cool the overheating reactors.

But former Fukushima plant manager, Masao Yoshida, ignored the order and secretly kept cooling the reactors, widely seen as averting a potential catastrophe.

Abe hailed the court’s decision, calling it “a victory of truth” on his Facebook page.

Kan did not issue an immediate comment on the ruling. ”

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Imperial research to help in nuclear clean-up at Fukushima — Imperial College London

” In March 2011, an earthquake off the east coast of Japan triggered a tsunami, which smashed into the Fukushima Daiichi Nuclear Plant. This led to explosions and a partial meltdown of three boiling water reactors and the mass evacuation by authorities of citizens living in the surrounding area.

Since the accident, water has been used to cool the damaged cores and reactor buildings. As part of the cooling process more than 3,760 tonnes of radioactively contaminated water is collected per day. Engineers on the site are using several decontamination facilities containing waste filters to extract radionuclides from the water, but as yet, the authorities do not have an agreed solution for safely immobilising this hazardous leftover waste material.

Now, researchers at Imperial’s Centre for Nuclear Engineering are collaborating with partners in the UK and Japan to develop processes for capturing and disposing of these radionuclides. The team is developing a glass material to mix with the waste filters, which are melted to form a solid composite material that will be stable for thousands of years and suitable for disposal deep underground.

In the new project, the team aim to determine whether this material will be able to withstand the heat generated by the radionuclides as they decay. If it is sufficiently robust, this should mean the nuclear waste can be collected without the need for additional complicated processes for permanently sealing in the toxic material, processes that would be time consuming and expensive.

Professor Lee, Director of the Centre from the Department of Materials at Imperial, said: “Multinational collaborations like this one are the key way for finding solutions to some of the world’s most pressing challenges. It is paramount that we find a safe and inexpensive approach to seal in and store this leftover radioactive material if the clean-up at Fukushima is to be a success. The results of this project may also have implications for the way we dispose of the UK’s legacy wastes, including those in the ponds and silos at the Sellafield storage and reprocessing site.”

During the clean-up process at the Plant, the contaminated cooling water is filtered through a material called High Dose Spent Absorbent (HDSA), which collects the radionuclides. The radionuclides generate heat as they decay in the HDSA and the Imperial team will develop computer models that quantify these heat levels.

The data generated by the models will enable the team to gauge whether the glass material they are currently experimenting with will be able encase the radioactive HDSA and withstand the heat generated.

The Imperial research will be carried out by the Professor Bill Lee and Dr Luc Vandeperre from the Centre for Nuclear Engineering at Imperial. Other related projects will be carried out by researchers from the University of Sheffield and teams at the Kyushu and Tohoku Universities in Japan.

The project is funded by the Engineering and Physical Sciences Research Council and is expected to run initially for two years. ”

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