Scientific Basis Inconclusive , and EPA and NRC Disagreement Continues

1 Mr. Chairman and Members of the Subcommittee: We are pleased to be here today to discuss the regulatory standards used to protect the public from the risks of low-level nuclear radiation. The scientific basis for these standards has been in question, as well as what level of protection is appropriate and adequate for the public. As you know, historically federal agencies, including especially the Environmental Protection Agency (EPA) and the Nuclear Regulatory Commission (NRC), have sometimes disagreed over how restrictive U.S. radiation standards should be. They have set differing standards, which include varying limits on radiation exposure to the public. The standards cover regulatory applications such as cleaning up major weapons production sites, decommissioning commercial nuclear power plants, and potentially constructing an underground repository for the disposal of highly radioactive waste at Yucca Mountain, Nevada. 1 our statement today addresses three issues: (1) whether current radiation standards have a well-verified scientific basis, (2) whether federal agencies, particularly EPA and NRC, have come closer to agreeing on exposure limits (how much radiation people can be safely exposed to) in the standards since we reported on this issue in 1994, 2 and (3) how implementing these standards and limits may affect the costs of nuclear waste cleanup and disposal activities. In regard to the scientific basis of radiation standards, we examined many scientific studies and interviewed recognized scientists in the fields of radiation protection and radiation research. In addition, we employed an expert consultant to help review scientific research correlating natural occurring (background) radiation levels around the world with local cancer rates. In summary: • U.S. radiation standards for public protection lack a conclusively verified scientific basis, according to a consensus of recognized scientists. Below certain radiation exposure levels, the effects of radiation are unproven, despite many years of research efforts. Evidence of 2 these effects is especially lacking at regulated public exposure levels—levels of 100 millirem a year and below from human-generated sources. 3 At these levels, scientists and regulators assume radiation effects according to what is commonly known as the " linear no threshold hypothesis, " or model. According to this model, even the smallest radiation exposure carries a cancer risk, and risks double as the exposure doubles. The model is useful and relatively simple, but controversial. Some scientists argue that the model overestimates radiation risks. Others take the position that the model underestimates these risks. Research into low-level …