Investigating the impact of nitrate-nitrogen contamination on uranium concentrations in Wisconsin groundwater

Uranium is a naturally occurring element in Wisconsin groundwater whose dissolution and transport of uranium in groundwater may be increased by anthropogenic changes to the geochemistry of the vadose and saturated zone. This study seeks to evaluate the potential for anthropogenic enhancement of uranium concentrations in Wisconsin groundwater by measuring uranium (238U)and nitrate during repeated sampling of a group of wells in uranium-bearing aquifers with a history of variable nitrate contamination and measuring the dissolution of uranium within the vadose zone of three soil profiles in uranium-containing carbonate/granitic parent material. The results of this short-term study of both groundwater and soil profiles should provide a better understanding of how uranium moves into groundwater and how that might be linked to anthropogenic changes to recharge water geochemistry.