New Modeling Approach Integrates Geochemical Processes into Field-Scale Simulation of Uranium Mobility in Groundwater at the Hanford Site


Uranium is a persistent groundwater contaminant at many DOE sites due to its adsorption onto mineral surfaces and/or precipitation of various uranium minerals within subsurface materials. These molecular-scale processes often exert a profound influence on uranium mobility at the field scale. One challenge in simulating uranium transport in the subsurface is the difficulty in coupling these molecular-scale geochemical processes controlling uranium concentrations with groundwater transport processes that occur at the field-scale. Researchers at PNNL have developed a modeling approach that incorporates these two types of information derived from laboratory and field experiments. The approach couples molecular-scale, laboratory-derived characterization of uranium geochemical properties with field-scale descriptions of transport processes obtained from tracer experiments. The new approach will be tested as part of the DOE-funded Integrated Field-Scale Subsurface Research Challenge (IFC) site at the Hanford 300 Area.


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