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Abstract
FEMWATER/LEWAST
A software package of two related numerical codes that are used together to delineate wellhead protection areas in agricultural regions using the assimilative capacity criterion, which considers environmental factors that reduce the concentration of contaminants transported to wellsCThe model accounts for (1) flow and transport in three-dimensional, variably saturated porous media (heterogeneous and anisotropic) under transient conditions, (2) multiple distributed and point sources/sinks, (3) and processes that slow contaminant transport. The model accepts four types of boundary conditions and can simulate adsorption, dispersion, and first-order decay.