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Fukushima Seven Years Later: Case Closed?

Investigators at the Fukushima power plant.

Official investigations into the Fukushima nuclear disaster conclude that upholding international safety standards alone guarantees nuclear safety, But the plant manager’s account of the catastrophe sheds  new light on the story, writes Franck Guarnieri of MINES ParisTech university. Courtesy: The Conversation.  

On March 11, 2011, a nuclear disaster struck Japan. The 9.0 magnitude Tohoku earthquake triggered a 15-meter tidal wave, which hit the Fukushima Daiichi Nuclear Power Plant approximately 45 minutes later. The plant’s power was knocked out and the backup generators crippled. After the emergency batteries were exhausted, three of the plant’s six reactors soon overheated, and at least two of the cores melted down, releasing immense amounts of radiation. While the reactors are now in theory stabilised, the work to understand and contain the damage continues.

In the seven years that have elapsed since the disaster, much has been written and said about its causes. Yet expert reports have paid little attention to the extensive testimony of Masao Yoshida, who was plant manager at the time and passed away in 2013.

One can only wonder about the decisions Yoshida had to make between March 11 and 15, 2011, to avoid the worst. And his gripping account calls into question some of the keystone principles of nuclear safety.

A ‘made in Japan’ disaster?

 The international community and the Japanese themselves quickly characterized the disaster as one that was “made in Japan”, meaning it was enabled by two circumstances specific to Japan: the country’s exposure to environmental hazards (earthquakes and tsunamis) and its cultural acceptance of collusion – real or imaginary – between corporations and government.

Calling Fukushima a “made in Japan” disaster focuses attention on the failures of a socio-technical system apparently disconnected from industry good practices

Management of the accident, both by its operator, the Tepco Group, and the Japanese government, has been condemned as ineffectual. Serious failings were attributed to Tepco, which was unable to prevent a nuclear meltdown and subsequent explosions. A rare bright point was the heroism of those working on the ground, who risked their own lives to avert an even greater disaster.

Calling Fukushima a “made in Japan” disaster focuses attention on the failures of a socio-technical system apparently disconnected from industry good practices and the norms of the International Atomic Energy Agency (IAEA). Moreover, its extraordinary scale allows it to be filed in the same historic category as another “aberrant” accident, Chernobyl.

The latter was attributed to gross Soviet negligence, implicitly reinforcing a utopian vision of a safe and reliable nuclear industry. But do the nature of the Fukushima disaster and the specificity of its causes really make it an exception?

There have been a wide range of official inquiries. In Japan, reports were issued by both a governmental investigation and a parliamentary commission. Investigations were also conducted by the International Atomic Energy Agency (IAEA), the American Nuclear Regulatory Commission (NRC), and the Nuclear Energy Agency of the OECD.

These analyses chiefly focused on the impact of the earthquake and subsequent tsunami on the nuclear power plant, the way the crisis was managed by the operator and the authorities, and on the cooperation between those onsite (emergency services) and offsite (Tepco staff). Hundreds of thousands of pages of reports have been published as a result. Ultimately, authorities unanimously concluded that upholding IAEA norms alone guarantees nuclear safety.

The Fukushima investigators all followed a pre-set formula, apparently designed solely to confirm hypotheses that would put events down to purely technical causes

But the majority of the thousand-plus hearings given by the people involved have remained confidential. This is troubling: Why would a democratic society allow hearings given to a parliamentary commission to remain secret?

During the Japanese government’s investigation, Fukushima Daiichi plant manager Masao Yoshida was interviewed for more than 28 hours, over 13 sessions. His testimony was only made public in September 2014 after critical reporting by Japanese media. Printed in Japanese on A4 paper, it filled more than 400 pages.

Shedding new light on the story

The Risk and Crisis Research Centre of the Mines ParisTech engineering school translated Yoshida’s testimony into French, the first complete version in a language other than Japanese. (A partial English translationexists, made available by the Japanese daily Asahi Shimbun, but it proved to be inaccurate on several crucial points, and is highly controversial.)

Given that France generates 76% of its electricity with nuclear power, the task of a complete translation should have been undertaken by a nuclear-sector operator. None volunteered, however, no doubt asserting that all had already been said and settled. The Fukushima investigators all followed a pre-set formula, apparently designed solely to confirm hypotheses that would put events down to purely technical causes.

The brutal reality of the situation in March 2011 was that it was no longer a question of managing a crisis, applying established procedures or rolling out plan A or plan B

Yet Yoshida responded to the investigators’ questions from an entirely different point of view, attributing his decisions and actions to the brutal struggle between men (himself and his staff) and technology or, more precisely, the machines (the reactors) that had suddenly gone out of control.

The brutal reality of the situation in March 2011 was that it was no longer a question of managing a crisis, applying established procedures or rolling out plan A or plan B. Day after agonising day, the Fukushima Daiichi power plant was an island, plunged into darkness, without electricity or emergency diesel generators, and almost completely devoid of resources.

Largely left to their own devices, Yoshida and the plant’s staff risked their lives at every moment. Wearing stiflingly hot protective wear and buffeted by aftershocks, they searched for slightest sound or visual clue in the absence of measurement data. Groping around the labyrinth of the ruined plant, they sought, more or less with success, to protect themselves from radioactive contamination in order to continue their work.

During the hearings, Yoshida confided his fears, doubts and beliefs. He lauded the commitment of his colleagues inside the plant, even as he deplored the absence or incompetence of those outside – Tepco headquarters, the government, the regulatory authority, and so on.

The emotional intensity of his account is both striking and moving. It shatters the all-too-bureaucratic certitudes that underestimate the complexities of situations, to the point of ignoring our humanity: the workers were facing the possibility of their own deaths and, above all, the deaths of their colleagues, their families and everything dear to them.

Almost miraculously, after four days of desperate efforts, the worst – the explosion of the Daiichi reactors, which could have threatened those at the close-by Daini and Onagawa plants as well – was narrowly avoided. Yet we have learnt almost nothing from this catastrophe, and the much larger one that was averted.

Beyond safety margins

Of course, re-examining safety standards is important, as are “hard core” safety systems (a kind of fortified line of defence against external onslaughts) and the costly installation of diverse backup power generators. Such measures certainly increase safety margins, but what about the bigger picture?

The creation of “special nuclear forces”, such as France’s nuclear rapid action force (FARN), is a perfect example of such a mind-set. They are on-call to restore installations in accordance with regulations on radiation exposure. But what will such teams do if levels of radioactivity are above those set out in the legislation? Could we count on their commitment, as Japan did for that of Masao Yoshida and his staff, at once heroes and victims, sacrificed willingly or under orders, in order to prevent a nuclear apocalypse?

Editor’s Notes:

This article was first published on The Conversation and is republished here with permission from the author and publisher.

Original Post

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Bob Meinetz's picture
Bob Meinetz on May 2, 2018 5:08 am GMT

Calling Fukushima a “made in Japan” disaster focuses attention on the failures of a socio-technical system apparently disconnected from industry good practices.

Franck, calling an accident with no casualties a “disaster”, a “catastrophe”, or saying “immense amounts of radiation” were released only focuses attention on why anyone making those irrational claims might feel entitled to do so.

In 2013 the World Health Organization (WHO) selected a team of independent international experts “for their expertise and experience in radiation risk modelling, epidemiology, dosimetry, radiation effects and public health” to conduct a Health Risk Assessment from the Fukushima-Daiichi accident. They found

…outside of the geographical areas most affected by radiation, even in locations within Fukushima prefecture, the predicted risks remain low and no observable increases in cancer above natural variation in baseline rates are anticipated. Some health effects of radiation, termed deterministic effects, are known to occur only after certain radiation dose levels are exceeded. The radiation doses in Fukushima prefecture were well below such levels and therefore such effects are not expected to occur in the general population.
The estimated dose levels in Fukushima prefecture were also too low to affect fetal development or outcome of pregnancy and no increases, as a result of antenatal radiation exposure, in spontaneous abortion, miscarriage, perinatal mortality, congenital defects or cognitive impairment are anticipated…
This health risk assessment concludes that no discernible increase in health risks from the Fukushima event is expected outside Japan. With respect to Japan, this assessment estimates that the lifetime risk for some cancers may be somewhat elevated above baseline rates in certain age and sex groups that were in the areas most affected.

Your article is an example of the human limits which are making the fight against climate change exponentially more difficult. Though nuclear energy is the safest form of dispatchable grid generation, though not a single death has yet to be attributed to radiation, 1,500 deaths were attributed to the panicked evacuation which followed it the explosion at Fukushima – due to exactly the same irrational fearmongering on display in your article. We truly have nothing to fear, but fear itself.

So if your unfamiliarity with nuclear energy causes you to be afraid of it, Franck, I won’t judge you – all I ask is that you stop scaring people needlessly so those who do understand it might use it to prevent some of the tens of thousands of casualties of coal smoke every year. The WHO and countless other health experts around the world understand what people really need to be concerned about. We should be listening to the experts, shouldn’t we?

Bas Gresnigt's picture
Bas Gresnigt on May 2, 2018 2:31 pm GMT

Same WHO report also states in the summary:

For leukaemia, the lifetime risks are predicted to increase by up to around 7% over baseline cancer rates in males exposed as infants; for breast cancer, the estimated lifetime risks increase by up to around 6% over baseline rates in females exposed as infants; for all solid cancers, the estimated lifetime risks increase by up to around 4% over baseline rates in females exposed as infants; and for thyroid cancer, the estimated lifetime risk increases by up to around 70% over baseline rates in females exposed as infants.

Furthermore at least two studies showed that the predicted risks by that WHO committee were too optimistic.
They found jump like increases of 15% (P=0.0009) in perinatal mortality in the 6 most contaminated*) prefectures (picture below; >10million inhabitants). Lower increases in 3 less contaminated prefectures and no increases in not contaminated prefectures.
No relation with tsunami damage.

All in all the IPPNW concluded towards ~20,000 (future) deaths due to the increased radiation.
*) Increased radio-activity mainly due to fall-out during the few occasions (~3% of the time) the wind did not blow all airborne Fukushima radiation immediately to the ocean.
The radiation level of most fall-out decreases to half every 30years (Cs-137, Sr-90).

Bob Meinetz's picture
Bob Meinetz on May 2, 2018 8:26 pm GMT

Bas, I don’t know where to start responding to this. Your image shows Fukushima Prefecture as “Highly contaminated” – is this from Hagen Scherb?

A March, 2018 reading in Fukushima City shows .15 µSv/h of background radiation:

That’s .05 µSv/h lower than my kitchen. Should I risk going into my kitchen to make a sandwich, or should I be hiding under my bed?

Jarmo Mikkonen's picture
Jarmo Mikkonen on May 3, 2018 11:30 am GMT

Katsumi Naganuma, 70, a former worker at Tokyo Electric Power Co., feels particular guilt because he knows that a 35-meter-high bluff overlooking the Pacific was shaved down to build the plant closer to sea level more than 40 years ago.

Tepco, assuming tsunami 3.1 meters or higher would never hit the coast, reduced the bluff by some 25 meters and erected the plant on artificially prepared ground only 10 meters above sea level.

This is the fundamental reason for the accident.

Engineer- Poet's picture
Engineer- Poet on May 3, 2018 1:05 pm GMT

One little detail not mentioned in this piece is that the plant manager was ordered by none other than the prime minister to NOT vent the reactor containments so that more cooling water could be added.  This led directly to the loss of the emergency reactor water feed pumps, the uncovering of the fuel and the subsequent hydrogen explosions.

Bas Gresnigt's picture
Bas Gresnigt on May 3, 2018 5:03 pm GMT

People tend to ignore risks on accidents which they were never confronted with, and whose consequences are unacceptable.
An example.

Dutch NPP Borssele was constructed in 1973 behind a dike, ~6meter below flooding sea level. Diesel emergency generators were unprotected against a flooding. E.g. their air-inlets would be ~4meter below water level.

After Fukushima a protection against flooding was installed around those diesel generators. Still never tested. Or any other good flooding test being done.
Installing those diesel generators 6meter higher was apparently too expensive.

While the official chance that the dike will brake is once in three thousand years, the NPP sticks to the idea that it belongs to the 25% most safe NPP’s in the world.

Still (due to the EU stress test?) there was some improvement regarding terror attacks. Until ~2013 the road on the dike was open and terrorists could drive trucks with mounted rockets or cannon’s (hidden behind some thin cover) on the dike and start firing to the dome and power installations (to take all cooling out), at ~70m distance, while they were 6meter above the foot of the dome and those installations.

Now the entrance to the road on the dike is blocked by some small concrete blocks which may cost terrorists a few minutes to take away. Apparently the owners didn’t want to invest more than the absolute minimum.
Despite that nearby Belgian NPP suffered not long ago from a sabotage act (the lubrication of the turbine bearings was stopped).

The problem that they are already making losses seems to overwhelm the idea to invest substantial to prevent a disaster. It’s easier to change risk awareness / estimations.

Jarmo Mikkonen's picture
Jarmo Mikkonen on May 4, 2018 8:42 am GMT


The only recorded cases of an armed attack or infiltration against an NPP have been carried out by Greenpeace and anti-nuclear activists.

Apparently they have only succeeded in convincing terrorists that NPPs are not profitable targets.

Bob Meinetz's picture
Bob Meinetz on May 4, 2018 4:14 pm GMT

People tend to ignore risks on accidents which they were never confronted with, and whose consequences are unacceptable.

Bas, people tend to ignore risks no one has been confronted with, because those risks don’t exist – they’re imaginary. As are their consequences.

It’s unfortunate some find imaginary consequences unacceptable, but they won’t find any answers looking for imaginary solutions to imaginary problems. The answer lies in evaluating risk based on available facts. And if they’re unavailable to do that on their own, counseling is in order.

Bob Meinetz's picture
Bob Meinetz on May 4, 2018 4:33 pm GMT

Jarmo, in all fairness to Katsumi, the decision to accept 10 meters as an elevation for Fukushima-Daiichi was hardly careless. He didn’t assume a tsunami > 3.1 meters in height would never hit the coast; he assumed it was highly unlikely. And he was correct: the Tohoku earthquake was a black swan event, the highest-magnitude earthquake in the area for over 1,400 years.

Risks in 1961 were calculated on slide rules, and were little more than educated guesses compared to the sophistication of contemporary probabilistic risk assessments. When San Onofre was closed in 2013, NRC had calculated the odds of a radioactive release endangering the public at one every 11,000 years. We’ll never know whether it was accurate – but if it was remotely close, the public had nothing to worry about.

Mark Heslep's picture
Mark Heslep on May 4, 2018 4:40 pm GMT

The IPPNW makes no “conclusions”, as it performs no scientific studies. Like Greenpeace, the IPPNW announces, claims, protests.

Mark Heslep's picture
Mark Heslep on May 4, 2018 4:51 pm GMT

The WHO goes on to say …

…These percentages represent estimated relative increases over the baseline rates and are not absolute risks for developing such cancers. Due to the low baseline rates of thyroid cancer, even a large relative increase represents a small absolute increase in risks. For example, the baseline lifetime risk of thyroid cancer for females is just three-quarters of one percent and the additional lifetime risk estimated in this assessment for a female infant exposed in the most affected location is one-half of one percent.

Thus the WHO finds any theoretical increase in the absolute cancer rate is so low that it will not be observable, and any theoretical deaths from cancer lower still. Any attempt to say otherwise without evidence is not science but counting ghosts.

Bob Meinetz's picture
Bob Meinetz on May 5, 2018 5:34 am GMT

Mark, off-topic: if you haven’t already heard, viewers of the CBS series Madam Secretary were treated to possibly the first pro-nuclear presentation on network TV last Sunday. Clip:

Michael Shellenberger, who was at least as dumbfounded as I was, wrote an article for Forbes on the import of a U.S. mass-media series embracing nuclear:

For 40 Years, Hollywood Has Tried To Kill Nuclear Power. Will It Finally Try To Save It?

Change is in the wind.

Bas Gresnigt's picture
Bas Gresnigt on May 5, 2018 6:46 am GMT

…imaginary. As are their consequences.

? Chance is high that a successful attack creates a much greater (10-1000 times?) damage than 9/11. So the attackers not only harvest eternal fame in heaven, but also on earth.
Luckily, until now it were beginners. But that can change.

Seems you exclude it, because the consequences are unacceptable.

Bas Gresnigt's picture
Bas Gresnigt on May 5, 2018 9:07 am GMT

Read e.g. this report.

Bob Meinetz's picture
Bob Meinetz on May 5, 2018 2:19 pm GMT

? Chance is high that a successful attack creates a much greater (10-1000 times?) damage than 9/11…

Bas, these fears are solely the product of your imagination. Any effort spent on educating yourself about nuclear energy would be richly rewarded in peace of mind.

Mark Heslep's picture
Mark Heslep on May 5, 2018 3:33 pm GMT

I’ve seen the IPPNW document, which is adjective and position laden propaganda (“catastrophe”, “disaster”) and not a report dealing with primary data.


And this

are heavily cited reports on the accident.

Mark Heslep's picture
Mark Heslep on May 5, 2018 3:41 pm GMT

Not so much shaving the foundation elevation but failure site backup pumps at higher elevation was a fundamental problem.

Mark Heslep's picture
Mark Heslep on May 5, 2018 3:44 pm GMT

Yes you for instance regularly fail to accept responsibility for increased coal emissions which, unlike Fukushima radiation, will kill people.

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