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Human error in Fukushima

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Fukushima accident. Who should be blamed: nature or man? Now that the Investigation Commission of the National Diet of Japan has published the official report on the nuclear disaster few doubts doubts remain. Man It was indeed a "man-made disaster."

The judgment of the Diet-appointed Commission is very harsh. Very Japanese, I would say. The shame of an accident that made headlines for at least two months on newspapers around the world had to be washed away with an abrasive sponge. This is precisely what the commission did with a clarity and ruthlessness unusual by Italian standards, always resorting to self-pity and self-justification. The accident occurred at the Fukushima plant - the report notes in its conclusions - is the result of collusion between government, the regulatory agencies and TEPCO (the company operating the six reactors). The combination of their negligence betrayed the Japanese nation's right to be safe from nuclear accidents. The disaster is clearly a man-made disaster. "We believe" conclude the ten experts of the Commission "that the underlying causes of the accident are to be found into the organizational and control systems that supported wrong decisions and actions". Collective and systemic fault, therefore, even cultural (the inveterate tendency of Japanese society to obedience and insularity), not attributable to individuals.

Let us briefly recall the facts with the words of Livia Marin, who devoted an interesting dissertation to the accident for her Master's degree in Science Communication at SISSA of Trieste ("Our view on the disaster", Trieste, 2012):

On 11 March 2011, Japan was shaken by an earthquake in the ninth grade of the Richter scale. An hour after the earthquake, several tsunami hit the Japanese coast with waves up to twenty meters. At the time of the earthquake, in the area most affected by the quake, 11 nuclear plants were in operation that automatically turned off thanks to the earthquake-proof security systems. One of the plant, however, the Fukushima Daiichi plant, began to have problems after the passage of the wave, which left it with no electricity, without emergency generators and unable to ensure cooling of the reactors. With the passing of time the situation worsened, leading to several hydrogen explosions, the evacuation of people in a radius of twenty miles around the plant and the fear of environmental contamination, both for the discharge of contaminated water into the sea and for the .explosions that released radioactive elements into the atmosphere.

Where did the authorities and Japanese engineers failed in containing damage, the meltdown of the core, the explosions and subsequent release of radioactivity?

First error, an assessment error: TEPCO immediately took for granted that the damage had been caused by the immense wave that hit the plant, dismissing the earthquake as a possible cause. It was not so. Most likely the earthquake damaged the instruments that could have ensured the safety of the plant. This is difficult to ascertain, however, because these instruments are inside the reactors and therefore inaccessible for years to come. More: it is very likely that the shocks had already caused a loss of cooling fluid inside reactor 1.

Second error, an organizational error: the plant engineers were not prepared to manage such a serious emergency. For example, they did not act as swiftly as they should have in the recovery of the Isolation condenser (IC) of Unit 1. Two reactors were out of service, electricity in the other four failed simultaneously and this certainly did not help. However, the engineers were not prepared and, incredibly, there was no instruction manual to address this kind of event.

Third error, the confusion of roles : the emergency response was affected by another deficiency. The chain of command - that according to procedures should have seen TEPCO management take hold of the situation supported by the various agencies - was disrupted. In fact, in the excitement of that 11 March, the Government crisis unit took over the management of operations, including because they did not trust TEPCO. In addition, the emergency was not immediately declared. A little like when Bush junior was reading bedtime stories to children while the Twin Towers were collapsing.
Commission recommendation: crisis management should not, for any reason, be left in the hands of the prime minister's judgment and skills. This is not his role.

Fourth error, the evacuation : which was dramatically slow and confused. This was due to improvisation, lack of clearly defined roles and lack of training.The government was slow in notifying neighboring municipalities of the accident and its severity. When the evacuation was ordered for those who lived within 2 miles from the plant, at 9:23 pm, only 20% of the population was aware of the accident. Most of the residents within 6 miles from the plant were informed of the the accident when the following evacuation order was issued at 5:44 am on 12 March. But even worse, many residents were evacuated in areas even more radioactive than the sites of provenance and left there alone for weeks.

Fifth error, the post accident management: the evacuees were 15 thousand, 167 workers were exposed to a cumulative dose of radiation of at least 100 millisieverts, while an area of 1,118 square miles in the Fukushima Prefecture (equivalent to the extension of Rome) received a cumulative dose of at least 5 millisievert/year (the threshold recommended for the general population is 1 millisievert/year). In areas where people were allowed to return (for the more contaminated ones, it will be necessary to wait decades) effective health system and support services (including psychological) to the population were not set up. Also risk communication was defective: even today, more than a year after the disaster, people have no clear knowledge about the acceptable level of radiation to which they can expose themselves in the various areas, much less about the problems for the different population groups: children, elderly, pregnant women.

Sixth error, the mindset: In the opinion of the Japanese Diet-appointed Commission the nuclear system's prevention and safety standards are not up to date. For example, they did not take into account the experience and consequent new rules, arising from the accident of the Twin Towers on 11 September. Fault of the "Insular attitude of Japanese regulators to ignore international safety standards". To this one should add the lack of transparency and collusion between regulatory agencies and energy producers. In practice, the overall system of Japanese standards, rules and laws on nuclear safety are aimed more at promoting nuclear energy than at protecting public health.

There are many other issues considered in the report (of which at the moment only a summary in English is available), which also mentions environmental and health problems that the Fukushima accident leaves open: in particular the mental health of people uprooted from their normal context of life and, who, therefore need adequate support. But also the uncertain budget of the environmental impact of radiations , which, due to rains and liquid leaks from the plant, have concentrated mainly in some lakes and on the seabed. Finally, the problem of decontamination of areas and the not at all easy management of future waste landfills and the thousands of tons of radioactive soil.

The official report of the Japanese Diet appointed Commission is available here

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