Few people probably missed the news about the accident at the Fukushima 1 nuclear power plant 12 years ago. Even the Japanese themselves often do not know that a similar situation happened twice at the same time - with the difference that in the second case the nuclear fuel managed to cool down. At the same time, there was a real threat that the same scenario would be repeated with a delay of half a day.
Fukushima No. 2 is located just 12 km south of the infamous Fukushima Daiichi. When the earthquake struck 12 years ago, its 4 reactors were all running.
Stop, cool, shut down
Director of the Naohiro Power Plant Maeda admits with distance that until then he only had indirect information about the tsunami and could not imagine what awaited him. That changed quite quickly when the wave overcame the barrier here too and flooded all 8 cooling exchangers.
Accidents in nuclear power plants have one rule in common: "Stop, cool, shut down." The first step was successful: all 4 reactors automatically stopped in an emergency. But when the inspection showed that the wave beat the doors to the exchanger buildings and there was water and fish everywhere clearly the second step will be a problem.
In order to even start cooling, it was first necessary to determine the exact extent of the damage. But the earthquake was not the only one - after the biggest one, other echoes continued and there was still the risk of another tsunami. Sending people to the exchangers was risky enough; at the same time , it was clear that waiting until the next day might mean that there would be nothing left to save. The situation was saved by Mr. Maeda , who started writing the times and intensity of these additional earthquakes on the whiteboard in the office: when everyone saw that the echoes were getting weaker and the intervals between them were getting longer, 4 groups went on a tour despite the tsunami warning still going on. The earthquake struck at 2:46 p.m.; the inspection started at 10 in the evening.
Restore cooling
Miraculously, only one of the 8 exchanger buildings survived. If it were cabled to the other three reactors, it would be possible to restart the cooling fairly quickly, but it would mean the risk of overloading the only remaining exchanger. Therefore, P. Maeda ordered the cable to be stretched from the waste processing building 800 meters away as the crow flies.
Due to fallen debris, the total length of the cable eventually reached 9 km. It normally takes twenty people a month to stretch something like this using heavy equipment. Here the cable was stretched by the efforts of 200 people in 30 hours. Meanwhile, news from Fukushima 1 was playing on TV. "Rather than fear that something similar would happen here, we felt a strong motivation not to allow anything like that," one of the technicians commented on the feelings of his colleagues.
You can still see where the cable went at the site today:
Meanwhile, the temperature and pressure in the reactors began to rise and it was necessary to start cooling. The last option was to release the pressure through the valves: the staff was pretty sure that there was no fuel damage here, so the probability of a radiation leak was low. However, if Fukushima 2, as the second power plant in the sequence, started to release pressure from the reactors, the regional panic could very well turn into a national one. This option has been rejected for now.
the SDF units ( equivalent of the army) brought the engine from the factory in Mie prefecture, several hundred km away. It was enough to remove it from the car and anchor it - but it was found that none of the employees of the power plant could do it. The heavy equipment was usually operated by employees of external companies, and the factory employees thus never needed to learn it. P. Maeda , at that time already two days without a minute of sleep, had only to laugh at his own incompetence.
Fortunately, one more extern was found, so on March 14th, at 1 a.m., the cooling was restarted. First in the 1st reactor, which showed the greatest instability. That was it - in another two hours the release of the pressure would be a must. 100 hours passed from the earthquake to the resumption of cooling.
The power plant stands, stereotypes fall
The story of the Fukushima 2 power plant is hugely significant for several reasons – and not just because another nuclear disaster was prevented here. For me, it is above all a story of people who were able to come together to solve a situation for which no one could ever have prepared them.
And it's also a story that breaks a lot of stereotypes we have about Japanese people. Mr. Maeda might have ordered his subordinates to go inspect the exchangers immediately, but instead of blindly serving the company, he preferred to protect their health. And if the stereotype of a Japanese person is someone who plans for a long time and then acts, this was an encyclopedic example of crisis improvisation and quick decision-making, made possible by years of experience and the high professionalism of all involved.
And although Tokio Electric, which operated the plants, is rightly considered one of the culprits of what happened at Fukushima 1, it is good not to forget the lessons that brought about a successful solution to the same problem just 12 kilometers to the south. Perhaps even just for something as small as the fact that power plant employees now have licenses and regular training on how to operate heavy equipment. It might save someone's life one day.
Jan Volný & #japonskepostrehy via Nippon.com
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