Yucca Mountain Standards Cover Longer Term Exposure
According to a Sept. 30 press release, the U.S. Environmental Protection Agency has established radiation standards for the proposed spent nuclear fuel and high-level radioactive waste disposal facility at Yucca Mountain, Nev. These standards will:
• Retain the dose limit of 15 millirem per year for the first 10,000 years after disposal;
• Establish a dose limit of 100 millirem annual exposure per year between 10,000 years and 1 million years;
• Require the Department of Energy (DOE) to consider the effects of climate change, earthquakes, volcanoes, and corrosion of the waste packages to safely contain the waste during the 1 million-year period; and
• Be consistent with the recommendations of the National Academy of Science (NAS) by establishing a radiological protection standard for this facility at the time of peak dose up to 1 million years after disposal.
The Department of Energy, which will operate the facility, is the only entity affected by the standards, which are in line with approaches used in the international radioactive waste management community. The Nuclear Regulatory Agency has not made a licensing decision on the repository.
For more specific information, visit http://www.epa.gov/radiation/docs/yucca/RIN%202060-an15-final-40-cfr-197amendments.pdf.
In 2001, EPA issued standards to limit radiation doses received by the public from Yucca Mountain. The disposal standards included a 10,000-year compliance period for protection of individuals and groundwater resources from potential release of radionuclides from Yucca Mountain. The agency required dose projections beyond the 10,000-year compliance period, but did not establish a specific compliance standard for the longer term projections.
In July 2004, the U.S. Court of Appeals for the District of Columbia Circuit ruled that the 10,000-year time period when the dose standards would be in effect was inconsistent with recommendations made by NAS in a 1995 report. The academy had recommended that EPA set a standard to limit exposure to individuals at the time of peak risk. The court did not rule that EPA's standard was not protective. It ruled that the standards were invalid to the extent that they did not extend to the time period recommended by NAS.
In August 2005, EPA issued proposed amendments to the standards to respond to the D.C. Circuit Court ruling. The standards maintained all the protections from the 2001 rule, retaining the 15 millirem per year dose limit for the first 10,000 years after disposal, and proposing a 350 millirem per year dose limit beyond 10,000 years up to 1 million years.
The average annual radiation exposure from both naturally occurring and manmade sources for a person living in the United States has been estimated to be 360 millirem per year.