I think you're asking, are they being evacuated because of current radiation levels, potentially higher fallout, or because of difficulty of supply?
Probably all three.
They have been told not to go outside, so how do they get supplies?
They may not have electricity or running water, so no electric stoves or refridgeration, food is spoiling and they can't cook.
And now "Late yesterday the government expanded the evacuation zone in response to the deepening emergency at Fukushima."
Here is one city that now must evacuate:
March 19 photos:
http://www.globalresearch.ca/index.php?context=va&aid=23787March 22 BBC audio interview:
http://www.bbc.co.uk/worldservice/news/2011/03/110323_minamisoma_nh_sl.shtmlMarch 26 now in evacuation zone:
http://www.independent.co.uk/news/world/asia/fear-and-devastation-on-the-road-to-japans-nuclear-disaster-zone-2253509.htmlFrom that last link: "Late yesterday the government expanded the evacuation zone in response to the deepening emergency at Fukushima."
<snip>
Only 20,000 of Minamisoma's population of 70,000 have stayed on here. In his office plastered with photographs of the aftermath, Sakurai Katsunobe, the town's lean and furious mayor, says residents have been left to fend for themselves. "Everyone here is angry with Tepco," he seethes. "They give us no information and no help."
Joking that he's a samurai, he vows to save his town with its crippled power plant, its poisoned rice paddies and terrified survivors. He is unlikely to get the chance. Late yesterday the government expanded the evacuation zone in response to the deepening emergency at Fukushima. Even the brave hangers-on will have to pack what they can and leave.
But until that order came, the few that remained were inhabitants of a kind of ghost world, removed entirely from the ordinary life they had once lived. Weighing that new reality in his office, Katsunobe stared at the images of devastation tacked to his wall. They were placed over the pictures that had decorated the room in more normal times. "We can't get supplies as drivers don't want to come here," he said. "We're like an island cut off from outside world."