Amendments to the U.S. Environmental Protection Agency’s Public Health and Environmental Radiation Protection Standards for Yucca Mountain, Nevada (40 CFR Part 197)

In 2001, as directed by the Energy Policy Act of 1992, the United States Environmental Protection Agency (EPA) issued public health and environmental radiation protection standards for the proposed repository at Yucca Mountain, Nevada. Several parties sued the Agency on numerous aspects of the rule. A Federal Court upheld EPA on all counts except for the compliance period associated with the individual-protection standard, which the Agency had limited to 10,000 years for a number of technical and policy reasons. However, the National Academy of Sciences (NAS) had recommended that the standard be set for the time of peak risk, within the limits imposed by the long-term stability of the geologic environment, which NAS estimated at 1 million years. EPA’s standards required that the Department of Energy (DOE) project doses to the time of peak dose but did not apply a compliance standard to these longer term projections. The Court ruled that EPA’s 10,000-year compliance period was inconsistent with the NAS recommendation. This aspect of the rule was vacated and remanded to the Agency for revision. In 2005, EPA proposed amendments to the standards. Following public hearings and a public review period, the final amendments were issued in September 2008. This paper discusses the new requirements.