(Maybe spoilers if you know zero about what happened in Chernobyl?)
Not sure. One episode of the show has guys going in the tank to fix something, and the whole horrible and dramatic point of that whole scene and event is that they had to do it in order to avoid the risk of an explosion which “could have been in the megaton range”. Theoretically. Ultimately they fixed whatever needed fixing and the explosion didn’t happen (as we know from history). The guys probably died very soon after because of radiation, hence the drama. So not sure what the problem is.