Assessment of Hanford Site Reduced Boundary Impacts: Limited Potential-to-Emit and Onsite Receptor Assessments

The U.S. Department of Energy's Hanford Site Comprehensive Land Use Plan initiated this work to prospectively determine the potential impact of a proposed reduced Hanford Site controlled access boundary to the regulatory requirements of several radiological air emission units at the Hanford Site 200 Areas. The reduced boundary would allow access to portions of the Hanford Site that are currently closed to the public. In addition, doses to several representative members of the public are presented. The assessments to determine the impact to the potential-to-emit (PTE) dose indicated in the Hanford Site FF-01 Air Operating Permit show that only one of the evaluated stacks, located in the Hanford Site 200 West Area, has the potential to increase its PTE dose. This increased PTE dose result would not change its classification from a minor emission unit to a major emission unit. Dose estimates for representative members of the public are based on average external exposure and inhalation dose estimates. Doses are presented for a Hanford Site tour participant, an intermittent hiker in the Wye Barricade region, and a hiker in a generalized portion of newly opened areas south and west of the Columbia River.