Skip to main content
U.S. flag

An official website of the United States government

Transient groundwater chemistry near a river: Effects on U(VI) transport in laboratory column experiments

January 1, 2011

In the 300 Area of a U(VI)-contaminated aquifer at Hanford, Washington, USA, inorganic carbon and major cations, which have large impacts on U(VI) transport, change on an hourly and seasonal basis near the Columbia River. Batch and column experiments were conducted to investigate the factors controlling U(VI) adsorption/desorption by changing chemical conditions over time. Low alkalinity and low Ca concentrations (Columbia River water) enhanced adsorption and reduced aqueous concentrations. Conversely, high alkalinity and high Ca concentrations (Hanford groundwater) reduced adsorption and increased aqueous concentrations of U(VI). An equilibrium surface complexation model calibrated using laboratory batch experiments accounted for the decrease in U(VI) adsorption observed with increasing (bi)carbonate concentrations and other aqueous chemical conditions. In the column experiment, alternating pulses of river and groundwater caused swings in aqueous U(VI) concentration. A multispecies multirate surface complexation reactive transport model simulated most of the major U(VI) changes in two column experiments. The modeling results also indicated that U(VI) transport in the studied sediment could be simulated by using a single kinetic rate without loss of accuracy in the simulations. Moreover, the capability of the model to predict U(VI) transport in Hanford groundwater under transient chemical conditions depends significantly on the knowledge of real-time change of local groundwater chemistry. Copyright 2011 by the American Geophysical Union.

Publication Year 2011
Title Transient groundwater chemistry near a river: Effects on U(VI) transport in laboratory column experiments
DOI 10.1029/2010WR009369
Authors J. Yin, R. Haggerty, D.L. Stoliker, D.B. Kent, J.D. Istok, J. Greskowiak, J.M. Zachara
Publication Type Article
Publication Subtype Journal Article
Series Title Water Resources Research
Index ID 70034959
Record Source USGS Publications Warehouse