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Three-Dimensional Subsurface Flow, Fate and Transport of Microbes and Chemicals (3DFATMIC) Model

This model simulates subsurface flow, fate and transport of contaminants that are undergoing chemical or biological transformations. The model is applicable to transient conditions in both saturated and unsaturated zones.


The flow module is a Galerkin finite element solution of Richard's equation. The transport module is a hybrid Lagrangian-Eulerian approach, with an adapted zooming and peak capturing algorithm.


This model can almost eliminate spurious oscillation, numerical dispersion, and peak clipping due to advective transport.

Version 1.0
Release Date August 1997
Development Status General Release
Operating System UNIX, DOS


3DFATMIC Source Code (ZIP)(151 K)

Input and Output Data Sets (ZIP)(2 MB)

US EPA. (1997) 3DFATMIC, Three-Dimensional Subsurface Flow, Fate, and Transport of Microbes and Chemical Model - User's Manual, Version 1.0 (PDF) (269 pp, 545 K, About PDF) Publication No. EPA/600/R-97/053.