To get independent answers about the risks faced by people, GlobalPost  turned to Arnold Gundersen, a 39-year veteran of the nuclear industry.  Now chief engineer at Fairwinds Associates, he has worked as a nuclear  plant operator and he served as an expert witness in the investigation  into the Three Mile Island accident.
GlobalPost: Officials have said the possibility of a large-scale radiation release is small. Do you agree?
Arnold Gundersen: I think that the probability of a large scale release is about 50-50, and I don’t call that small.
GlobalPost: Why do you think that?
Gundersen: For several reasons. One, you’ve got three  reactors involved. Two, you’re already picking up radiation on aircraft  carriers a hundred miles away at sea, on helicopters 60 miles to the  north, and in town. So clearly, as these plants become more and more  difficult to control, it becomes quite likely that a containment now  will have a gross failure. And a gross failure will release enormous  amounts of radiation quickly.