Fig. 2. Second experiment of Silliman et al. (2002) demonstrating infiltration within a homogeneous sand. The average groundwater flow is from left to right. The water table is marked with the dashed line. The solid line indicates the approximate upper limit of the capillary fringe. The dye was added as a slug input within the small injection region labeled "Dye Input" in the figure. The slug was flushed into the sand under a uniform infiltration distributed across the surface of the sand. (After Silliman et al., 2002.)