Front-tracking model for convective transport in flowing ground water

A finite-difference numerical model that simulates the convective transport of water or tracer particles through porous media is described. It can be applied to one- or two-dimensional problems involving either steady-state or transient flow. The model tracks representative water or tracer particles, initially located along specified lines, as they move in response to the groundwater velocity filed. Aquifer properties may be both anisotropic and nonhomogeneous. Included in the report is a listing of the program along with input formats and test problem results. The front-tracking model provides a useful first approximation determining the movement of solutes in an aquifer, particularly in cases when dispersion and dilution is of minor consideration. (USGS)