Water Resources Research Act Program

Details for Project ID 2010ID158B

Determining the Cause of Elevated Uranium Concentrations in the Shallow Treasure Valley Aquifer

Institute: Idaho
Year Established: 2010 Start Date: 2010-03-01 End Date: 2011-02-28
Total Federal Funds: $5,950 Total Non-Federal Funds: $14,523

Principal Investigators: Shawn Benner

Project Summary: Uranium represents an important emerging threat to groundwater-based drinking water supplies in Idaho. In the most populated region of the state, the Treasure Valley, this problem is particularly acute and is a subject of concern to the Idaho Department of Environmental Quality (see attached letter of support). Initial observations suggest that uranium contamination is the product of surface irrigation practices, highlighting the need for water quality considerations during the conjunctive management of surface and groundwater systems in the Treasure Valley. This project will complete a research effort, initiated by the Idaho Department of Environmental Quality, to identify the cause of elevated uranium in the Treasure Valley aquifer and determine how surface water management can alleviate this groundwater problem. This objective will be achieved through the application of a state-of-the-art isotopic signature approach to link dissolved uranium in the aquifer to its solid phase source. Linkage to surface sources, including fertilizer and surficial soils, will be indicative of an irrigation influence. If deeper aquifer sediments are implicated, surface water management is less likely to influence future uranium concentrations. This analytical technique has potentially widespread applicability to a range of water resource and conjunctive use issues across the State of Idaho.