Our summary post (with links to articles) on "Nuclear plant in Fukushima has lost nuclear waste containment integrity" excerpts Maggie Gunderson's article published at Green Mountain Daily (this must-read article contains a video and important background links). and other similar expert evaluations.
Maggie Gundersen's latest: "It Just Got Worse: 3 nuke plants in process of meltdown and 4th has fire in spent fuel pool":
As you all know, one nuclear plant had the top blow off and began to leak radioactivity into the air (Unit 1, built in 1970). Then a 2nd one it exploded yesterday (Sunday) (Unit 3 built in 1974) Tonight we received word at 8 pm that Unit 2 exploded (built in 1972 - the same year as Vermont Yankee). Each explosion has gotten worse, and the third explosion has severely damaged the containment building...
Arnie's interview here in the Global Post was spot on regarding a reactor core melt and containment failure:
GlobalPost: The ultimate risk in any nuclear accident is that the heat can grow so intense that the steel containment vessel is ruptured, releasing a large amount of radiation. You say there's a 50-50 chance of this happening. What kind of health effects can we expect?
Gundersen: First, it's important to know that this steel containment is about an inch thick. It's not some massive battleship of steel. The reactor is already open, because the pressure relief valves have to stay open.
On top of that, these containments have already breached. We saw iodine and cesium in the environment before the first unit exploded. When you see that, that's clearly an indication that the containment has breached.
Now, is it leaking 1 percent a day? Probably. Is it leaking 100 percent a day? No. I think for the neighboring towns out to 2 miles, they won't have anybody back in them for five years. Out to 15 miles, I doubt you're going to see anyone back for six months. And that's in the best case, without a meltdown.
If we have a meltdown, I don't think anyone will be back within 20 miles for 10 or 15 years.