Examining Initial Evacuation-zone Setting by Japanese Government

The following article was written as an assignment for the Public Speaking class.

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We Japanese had a huge big disaster in the Tohoku prefectures of Japan on March 11, 2011. Many people were lost and are still missing. The Japanese government and many foreign embassies issued evacuation advisories to save their countrymen immediately after finding out the explosion of the nuclear-power plants in Fukushima and the possible risk of radioactive contamination. However, there were clear differences in the evacuation advisories issued by the Japan authorities and their foreign counterparts. In this article, I would like to write about these differences and give my opinions on the appropriate instructions of those authorities.

The U.S. Government issued its evacuation advisory on March 17th recommending that U.S. citizens should stay 80 km away from the Fukushima Nuclear Power Plants. It also arranged charter planes to evacuate its citizens to other Asian countries. France also took very quick action to evacuate its people. It recommended that its nationals get out of the Kanto area or Japan immediately. Not only did it charter planes to evacuate them to their home country, but it also prepared iodine tablets for them at the Embassy just in case of radioactive contamination. As a result, a total of 4,000 out of 7,000 (that's about 60% of) French nationals left Tokyo after the quake. The British Government also issued the same advisory as the U.S. It chartered flights to Hong Kong and also a bus from Sendai to Tokyo. China evacuated 6,000 of its nationals to the nearby Nigata Prefecture and brought them back home from there. Other foreign countries including Australia, South Korea, Germany, Russia, Switzerland, and Austria basically issued only the same 80-km evacuation advisory that the U.S. issued.

On the other hand, there is a big gap between the U.S. and Japan. The Japanese Government asked the residents who live within a 20-km radius of the power plant to evacuate and also asked the ones who live within another 10-km radius to stay indoors. Since it issued this announcement on the 12th, right after the explosion at the power plant, the Japanese Government has been criticized regarding its evacuation range. Some people said the Government underestimated the risk of radioactive contamination and the evacuation zone should have been widened to 80 km, the same as the U.S. Later, a month after the earthquake, the Japanese Government partially increased the evacuation zone, adding five local areas outside the initial 20-km zone where the radioactive contamination is estimated to be more than 20 millisieverts per year. 20 millisieverts per year is the maximum limit for an adult to expose to radiation in emergency situation. This was recommended by the ICRP (the International Commission on Radiological Protection) after the earthquake. Usually in the Western countries, this amount of exposed dose is allowed only for nuclear industry employees.

From a risk management point of view, I think both the Japanese and foreign governments made appropriate decisions on the question of evacuation-zone range at that time. We have to understand that they were in totally different situations. Although they both tried to evacuate their own nationals, Japan had to evacuate a huge amount of people from the stricken zone from immediate health reasons, whereas foreign governments had to evacuate only very few nationals from the evacuation zone. As the U.S. Ambassador announced, they advised the evacuation "as a precaution"(U.S. Embassy), rather than as an immediate health threat. It was not even forced evacuation. For the foreign governments, it would be extremely difficult to find their nationals and evacuate them once the accident happened and the situation became chaotic. To avoid the possible worst-case scenario, they did what they could do beforehand. It was also manageable for them to evacuate a few hundred or thousand of their nationals to other countries by chartering planes just to ease any concerns of those nationals and their families back home.

First of all, why did the U.S. say 80 km? 80 km is 50 in miles and "50 miles" is an easy number to say or remember. That's what I thought at first, but it turned out that the number is not based on any facts.According to ABC News, on April 7th after almost a month since the earthquake, the members of the U.S. Nuclear Regulatory Commission's Advisory Committee on Reactor Safeguards told an independent advisory panel that they determined the distance based not on the actual data but on the assumptions about the reactor's condition. This is because they couldn't get any data off the site then. Since their scenario assumed 100% damage to the reactor, their evacuation range was greater.

However, it was proven that the Japanese Government set an appropriate evacuation zone. It issued its evacuation advisory based on its risk management procedure. The 20-km range is considered to be safe enough even by several other foreign authorities. In fact, when the Three Mile Island nuclear accident occurred in the U.S. in 1979, the first evacuation zone was only 5 miles (8 km) from the nuclear power plant (they widened it to 20 miles (32 km) two days later). In the case of the Chernobyl accident in 1986, it was 18.75 miles (30 km). According to BBC News, the U.S. Government announced later that its 80-km evacuation advisory "did not imply a lack of confidence in the Japanese warnings"(BBC). In reality, it is impossible to evacuate the whole population from a 50-mile (80-km) evacuation zone that covers all Fukushima Prefecture with its population of two million plus.

Since the situation was uncertain at that time and was viewed differently by the Japanese Government and foreign authorities, their decisions were different despite the fact that they had the same information and were responding to the same accident. I personally think the Japanese Government made many questionable decisions after the disaster, but regarding the range of the evacuation zone, it is wrong to criticize them for the initial setting.