More On Japan

I think the news about Japan and a potential meltdown has been a bit misleading. From a colleague of mine, here is an excerpt from an email written by a distinguished nuclear physicist from the University of Michigan regarding the crisis in Japan:

"I'm not expert on this particular engineered system (not a nuclear engineer); but rather a nuclear physicist. That said, I see no reason to expect that, even if attempts to cool these cores completely failed and there was a worst case so-called meltdown of the entire core, the ultimate container vessel would not completely contain the entire mass and it's radiation indefinitely.

The radiation releases to date are quite well understood as simply radiation entrained in steam that undergoes controlled releases as it is generated in cooling the rods with water. The rods are indeed cooling and the steam releases are apparently decreasing. Meanwhile spent rods in the pools are not in danger of some full meltdown, but need to be covered in water to dissipate heat and suppress radiation.

These are of course serious matters; but no one should be telling the public that a 'meltdown' would release large amounts of radiation or contaminate large areas as long as there is no evidence that the ultimate container has ever been damaged. I have seen no such claims."