Because Chernobyl contaminated the environment much more severely, whereasthe Fukushima nuclear meltdown was not very serious.
There have been two major nuclear accidents in the modern era, one at the Chernobyl nuclear power plant, which shocked the world, and the other at Fukushima in 2011. The Fukushima nuclear accident was caused by the March 2011 earthquake in Japan, which triggered a tsunami due to the massive earthquake. The cooling system of the Fukushima nuclear power plant was damaged and the cooling system was damaged outright. The reactors overheated, so needless to say, explosions and leaks ensued. Everyone has an impression of the Fukushima nuclear accident, but it's not a deep impression, and I think the aftermath of this accident passed quickly.
In case you didn't know, the Fukushima accident is the same as the Chernobyl accident, a major nuclear accident, which the IAEA categorizes into seven different levels based on their severity. Level 5 and above are major nuclear accidents with on-site risk, while level 7 is the highest level and is a very large nuclear accident. Both the Chernobyl nuclear power plant accident and the Fukushima nuclear accident were categorized as Level 7. The reason we believe that the Fukushima nuclear accident was not as horrific as the Chernobyl nuclear power plant accident is that the consequences of the Fukushima nuclear accident quickly disappeared due to Japan's low-profile handling of the situation. Public opinion can dissipate, but the disaster caused by a major nuclear accident will not dissipate, and the limit is now approaching. We can now see that many blue tanks have been built on the former site of the Fukushima plant to store nuclear-contaminated wastewater.
Storing water in this way is not always a problem, but we must find ways to reduce the waste water. There are two ways to reduce contamination, one is filtration and the other is isolation. Filtration is to create a filtration system to remove contaminants from the wastewater and then discharge it. Isolation is to isolate the groundwater from the reactor, and the method used in Japan was to build permafrost walls. As a result, there were too many gaps in the permafrost walls for effective isolation, and eventually the water had to continue to be stored. The total storage of wastewater from the Fukushima nuclear accident now exceeds 1.1 million tons, which is very alarming.