"BETHESDA, Md. — A competition between nuclear waste dumps has pulled the Nuclear Regulatory Commission into an unusual reconsideration of its rules to allow moderately radioactive materials to be diluted into a milder category that is easier to bury.

At issue is whether a site in Utah that is licensed to accept only the mildest category of radioactive waste, called Class A, could accept far more potent materials, known as Class B and C wastes, by blending the three together.

Even low-level radioactive waste is a growing problem, with few licensed repositories to dispose of it. The problem dates from the early 1980s, when Congress said that the federal government would take care of high-level waste, like spent fuel from nuclear power plants, but that the states would have to find sites for low-level material, like the radiation sources used in cancer treatments and industrial X-rays, and filters used in nuclear plants."

Matthew L. Wald reports for the New York Times June 17, 2010. [2]