MT3D-USGS – Developed by USGS and SSP&A

MT3D99 – The Leading Code for Analyzing Contaminant Migration in Groundwater

MT3D99 builds on the strengths of the public-domain MT3DMS code, and includes significant new enhancements to improve performance and increase the functionality of the MT3D96 and MT3DMS codes.

KEY FEATURES

• Implicit Solver: The iterative solver is based on generalized conjugate gradient methods with the highly efficient Lanczos/ORTHOMIN acceleration scheme and enables the user to solve a wide array of problems using much less computer.
• TVD Solution Scheme: The third-order TVD (total-variation-diminishing) scheme for solving the advection term is mass conservative and minimizes numerical dispersion and artificial oscillation. It has been shown to be effective where other solution techniques fail.
• Dual Porosity Option: The optional dual-porosity advection-diffusion model provides a more effective approach than the standard single-porosity advection-dispersion model for modeling solute transport in fractured or extremely heterogeneous porous media.
• Nonequilibrium Sorption and Monod Kinetics: The nonequilibrium sorption model enables the user to examine the role of sorption in solute transport and remediation processes without the restrictive local-equilibrium assumption. In addition to the first-order kinetics, MT3D99 supports zero-order and mixed-order Monod kinetic reactions.
• Multispecies Reactions: MT3D99 can handle BIOPLUME-type aerobic and anaerobic reactions between hydrocarbon contaminants and any user-specified electron acceptors, and parent-daughter chain reactions for inorganic or organic compounds. This enables MT3D99 to analyze natural attenuation and bioremediation without using an add-on package. The multispecies reactions are fully integrated with the MT3DMS transport solution schemes, including the implicit solver.
• Automatic Restart Option: MT3D99 supports a new automatic restart option to greatly facilitate the continuation of a run from a previous simulation.
• Complete Mass Budgets: MT3D99 computes cell-by-cell mass flux and mass storage terms. This enables the user to compile a detailed mass budget for any subregion of the model grid.
• Postprocessing Programs: MT3D99 includes several useful and flexible postprocessing programs: PostMT3D/MODFLOW for creating 2D and 3D data files for any graphic and visualization software package including Surfer and TecPlot; HCOMP for computing residuals and summary statistics between observed and model-calculated heads and concentrations; and FBUDGET for calculating detailed groundwater flow and solute mass budgets in any user-specified subregion of the model grid.

Why choose MT3D as your 3D Solute Transport Simulator?

• Full Compatibility with MODFLOW: MT3D99 is designed to work directly with the industry-standard groundwater flow codes MODFLOW-88 and MODFLOW-96. Other flow models can also be supported by modifying the LinkMT3D package for MODFLOW.
• Three Major Classes of Transport Solution Techniques: MT3D99 combines three major classes of transport solution techniques in a single code, namely, the standard finite difference method; the particle tracking based Eulerian-Lagrangian methods; and the higher-order finite-volume TVD method.
• Wide Acceptance and Support: MT3D has been successfully applied to model thousands of sites and is widely accepted by regulators and the groundwater consulting and research community. In addition, MT3D99 is backward compatible with all previous versions of MT3D, supported by all major graphical pre- and post-processors.
• Free Technical Support: S.S. Papadopulos & Associates, Inc. stands behind this product 100% and provides complete documentation and free technical support for MT3D99 users.