PESTFADE, A NEW PESTICIDE FATE AND TRANSPORT MODEL - MODEL DEVELOPMENT AND VERIFICATION

The development and verification of a new contaminant transport model, called PESTFADE (PESTicide Fate And Dynamics in the Environment), is described. PESTFADE is a one-dimensional transient mathematical model that can simulate simultaneous movement of water and solutes in the so il environment, as affected by runoff, leaching, dispersion, uptake, m acropore flow, sorption/desorption, volatilization, heat flow, and che mical and microbial degradation. The governing partial differential eq uation for coupled water and solute transport is solved by the Numeric al Method of Lines (NMOL) technique. The various submodels of PESTFADE were verified against analytical solutions available for simplified c ases. There was a close agreement between the numerical model and exac t analytical solutions.