Carrie Nuva Joseph

Soil, Water and Environmental Science

Management of engineered uranium disposal cell covers and community risk perceptions for legacy sites located in Native American communities

There are approximately 15,000 abandoned uranium mines (AUM) in the western United States, of which 500 AUMs are located in the Colorado Plateau Four-Corners region. Uranium mill tailings referred to as legacy waste, compromise the largest volume of any category of radioactive waste in the nation. Today, the Department of Energy Legacy Management (DOE-LM) is responsible for long-term stewardship and maintenance of inactive uranium processing sites that have been remediated to prevent further migration and exposure of tailings to the environment and surrounding communities. In collaboration with the DOE-LM, I am investigating the impact of climate change and community adaptation on the long-term performance of disposal cell covers for uranium mill tailings located in Native American communities, as well as how these communities have adapted to and perceive these areas. Specifically, I am interested in how abiotic engineered cell covers may be candidate sites for future conversion to vegetated evapotranspirative caps for arid to semi-arid climates. The objectives are to: 1) assess above-ground tissue of plants encroaching engineered cell covers for concentrations of uranium, radium, selenium, molybdenum, thorium, arsenic, lead, and manganese and compare them to control sites; 2) determine if above-cell plant tissue is accumulating to toxic levels that may create an exposure pathway,  3) identify climate scenarios for site locations and determine how short and long-scale climate projections will influence spatial and temporal plant distribution for specific woody species; and 4) evaluate the risk perceptions of Hopi villages located five miles downstream of one site location. To date, risk perception and stakeholder outreach to the Hopi communities has been absent. This study will help inform how land use, water use, and sustenance practices may contribute to environmental health disparities of one of the few tribes maintaining physical continuity with their ancestral homeland.