"Basically, the commercial users have to make changes to their reactors to be able to use the fuel and, in some tests that were done, there were concerns about the MOX fuel not being reliable," Mr. Young said. "When you're using fuel in a reactor that costs billions of dollars to build, you want a very reliable fuel."
"The process of creating the commercial fuel is risky. Once it's in the reactor and irradiated, at that point the plutonium is safe from theft. But getting it to that point in the way the MOX approach does is less safe than leaving it where it is now," Mr. Young said.