2-DIMENSIONAL MODELING OF ADVECTION-DOMINATED SOLUTE TRANSPORT IN GROUNDWATER BY THE MATCHED ARTIFICIAL DISPERSIVITY METHOD

A methodology for modeling, in two dimensions, the transport of dissolved constituents in steady groundwater flow is presented. The model aims at the efficient confrontation of the difficulties associated with advection-dominated conditions (oscillation-free resolution of sharp fronts). Employing a spatial splitting algorithm within the framework of the (curvilinear) principal directions of transport formulation, it computes transport along streamlines by a variant of the pseudoviscosity method. The algorithm is subject to mild grid design constraints that afford efficiency in terms of CPU time and storage; its accuracy is tested against analytical solutions. The model is also applied to the simulation of the chloride plume observed under the Borden landfill in Ontario, Canada. Model calibration issues are discussed.