A simulation model describing nitrate movement through a potato-cropped Plain-field loamy sand is described. Physical processes modeled include dispersion, convection, plant uptake, nitrification, and mineralization. The soil water flow regime is treated approximately by dividing the soil profile into three layers between the surface and the water table and generating water flux and water content profiles by solving a series of mass balance equations which include submodels for evapotranspiration and internal drainage. This information is combined with the solute equation and is solved numerically by the finite element method. Model predictions of nitrate movement often qualitatively agreed with field data when symmetrically comparable profiles were used. Nonuniform infiltration across the hill-furrow unit induced large local variability in solute transport. Predicted and measured nitrate concentrations in lysimeter leachates were in closer agreement when the nonuniform infiltration pattern was incorporated into the model.