Fukushima Daiichi Nuclear Power Plant Accident "Water Cannon" The Eve

Water cannon by helicopter from the sky by the Self-Defense Forces in the accident of TEPCO's Fukushima Daiichi nuclear power plant 10 years ago.

The night before, the details of the exchanges between the Self-Defense Forces at that time and the top US forces in Japan were revealed from the records.

The American side suggested that if the situation at the nuclear power plant deteriorated, Americans living in Japan could be evacuated, and immediately after that, SDF executives decided to release water even in high radiation doses.

This exchange was written in his notebook by Koichi Isobe (63), who was in charge of liaison and coordination between the Self-Defense Forces and the US Army as the Director of Defense Planning Department of the Joint Staff Office at that time.

Ten years ago, it was pointed out that the water that cools nuclear fuel would evaporate at Unit 3 of the Fukushima Daiichi Nuclear Power Plant, and the Self-Defense Forces attempted to discharge water from a helicopter on March 16 at the request of the government's response headquarters. ..

However, the radiation dose in the sky was as high as 250 millisieverts per hour at an altitude of 30 meters, so I gave up the water discharge on that day.

According to Mr. Isobe's record, a telephone conversation was held from 10:15 pm that day between the then top of the Self-Defense Forces, Chief of Staff, Joint Staff Ryoichi Oriki, and the top commander of the US Forces Japan, Burton Field.

The note states that Chief of Staff, Joint Staff Oriki said, "I tried today, but I couldn't do it. I'll try again tomorrow."

In response, Commander Field said, "I don't know the exact situation. Experts don't fully understand it." "It is possible to evacuate Americans if the nuclear power plant becomes more severe. It depends on the president's decision." It is recorded as.

Regarding this, Mr. Isobe said, "It was shocking that the United States, an ally, took the situation so seriously that it considered the evacuation of the people. The background was that Japan did not fully respond to the United States seeking information. I think. "

According to Mr. Isobe, the Chief of Staff, Joint Staff Oriki and the Chiefs of Staff, Joint Staff of Land, Sea and Air gathered after 11:00 pm on that day.

At this point, the next day, he decided to "spray water even at risk."

Then, at 9:48 am on March 17, the Self-Defense Forces began discharging water to Fukushima Daiichi Nuclear Power Station Unit 3 with two helicopters.

The amount of radiation in the sky is 87.7 millisieverts per hour at an altitude of 90 meters.

The value was still high, but it was judged that it was within the permissible range, and the water was discharged after taking measures to prevent the exposure of the members as much as possible.

Even now, 10 years after the nuclear accident, it is unknown how effective this water discharge was.

However, Mr. Isobe said, "After the water discharge, it was meaningful as a message that the United States and the world evaluated the actions of the Self-Defense Forces and showed Japan's readiness to deal with the nuclear accident." It was a situation that could crack. I think we must pass on the lessons learned at that time, such as the importance of acting independently in the event of a crisis. "

Former Commander of the U.S. Forces Japan "Irritability without Information"

Burton Field, the head of the U.S. Forces Japan, responded to NHK's interview, looking back on the response to the nuclear accident, saying, "I don't think Japan or the United States was hiding anything, but there was a communication problem. I was frustrated that no one knew what was going on inside the nuclear power plant and the information wasn't coming out fast enough. But wait a minute because the worst disaster in the world happened. I needed it. "

In addition, over suggesting the possibility of evacuation of Americans to Chief of Staff, Joint Staff Oriki, Mr. Field said, "If a certain amount of radioactive material is released from the Fukushima Daiichi nuclear power plant to the American side, Yokota Air Base and There was speculation that people around Tokyo, such as Atsugi base, would be forced to evacuate. "

On the other hand, "For whatever reason, if we evacuate, I was going to evacuate at the end, and later on what was happening at the nuclear power plant and what the weather patterns were like. When I started to know, I realized that there was no such danger. "