|Categories||Fact Sheet, Soil and Groundwater|
|Create Date||February 4, 2014|
|Last Updated||February 4, 2014|
Uranium has been recognized as one of the most widespread groundwater contaminants at the U.S. Department of Energy’s (DOE) Hanford site, Washington State. In oxidized groundwater conditions that are typically present at the Hanford site, soluble uranyl ion (UO22+) creates strong complexes with carbonate and Ca2UO2(CO3)3o and UO2(CO3)22- are the predominant U(VI) aqueous species. The concentration of uranium exceeds the maximum contaminant level for drinking water of 30 μg/L required by EPA. Injections of a soluble sodium tripolyphosphate amendment into the uranium contaminated groundwater and soil have been shown to effectively sequester uranium through the formation of insoluble uranyl phosphate minerals. The study evaluates the effect of bicarbonate concentrations, T, and pH on the dissolution kinetics of synthetic Na meta-autunite. This was accomplished through a series of dissolution experiments conducted in a single-pass flow-through (SPFT) reactor.