Physical simulations of two-dimensional infiltration of dense nonaqueous phase liquid (DNAPL) contaminants in homogeneous sand- and silt-size glass bead, compacted clay and layered samples were performed under elevated gravity levels in thegeotechnical centrifuge at UC Davis. For the imposed boundary conditions of falling DNAPL head and static water table, and the high viscosity, low density DNAPL used in the experiments, a stable, approximately semi-circular DNAPL front was observed in all the homogeneous granular samples. The velocity of infiltration decreased with time, until DNAPL movement eventually reached a halt at an average DNAPL saturation of 70 to 80%. For the clay specimens, the infiltration of the DNAPL followed athree-dimensional network and was dominated by the macroscopic features of the clay, resulting in an average DNAPL saturation of 35%. The movement of DNAPL in the layered models was dominated by lateral spreading in the coarse layers.
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