> Fukushima did not blow stuff into the atmosphere

Well, that is actually not right. During the accident radioactive water vapor and other gases were released into the atmosphere due to the explosions. Its correct though that, most of it was washed out by rain quickly being diminished into the ground water or carried away onto the ocean.

More importantly a significant portion of the radioactive water seeped into the groundwater, which will have unknown effects in the future.