Well, i don't know what was Dmytry meaning in his post but from my standpoint, I've had the impression that the 20kms/30kms zone has been very quickly drawn on the map and that after that, the communication seem to have been very confusing between orders given (evacuate in the 20kms/stay inside for 20 kms/30 kms which is, let it recognize, adapted for a short time but not for more than a month!) and some data released which gradually showed that these orders where sowewhat inappropriated for some areas (like the North west Litate zone for example). The "evacuate voluntarily advice" (20k/30k) was quite surprising also. Then they moved to a new recent position adding some specific zones outside of the circles but it required a "fair amount" of time, as if they were "sticking" very long to their first circles, drawn very quickly (at a time US forces were talking about a 80 kms zone by the way).
I understand that evacuation is not easy, and that's also part of the dangers related to that kind of accident: it can add or remove a lot of effects on people depending if it is done in an efficient way or not. But as i said more than a month ago, infos and decisions have to be consistent otherwise people get lost, and a lot got lost effectively (remember these people going back because they didn't feel that there was a danger as announcements done were always very "soft" (no risk, no danger, don't be overly concerned, and so on). It's certainly good to avoid panic, but on the other side, if communication is so soft and inconsistent that some people think "that's a big deal about nothing, i go back there" -which happened- then that's also a problem in my opinion! Panic is not only "rushing all in the same direction", it can also be create a situation where people don't know what to do in their everyday life ("ok i stay inside but after one week, two weeks, 3 weeks what do i do"...) and go in various contradictory directions because what they perceive is contradictory...