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MT3D99
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3-D Contaminant Transport Modeling for MODFLOW Models.
Now Includes Faster Solvers and Built-In Reactive Transport Processes! |
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overview
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MT3D99 is a comprehensive three-dimensional mass transport
model for simulating advection, dispersion, and chemical reactions of a single
species contaminant in ground water systems. The model program is based on a
modular structure to permit simulation of transport processes independently or
jointly. MT3D99 is capable of simulating advection, dispersion,
first-order decay, or production reactions, and linear and non-linear sorption.
MT3D99 is linked to the USGS's three-dimensional groundwater model
MODFLOW and can be easily applied using a graphical pre-and post processor like
Visual MODFLOW Premium. MT3D99
is an ideal tool for simulating groundwater plume migration in either two- or
three-dimensional groundwater flow systems. |
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Input
Features
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The MT3D99 model input is compatible with standard MODFLOW data
files, including three- dimensional transient flow fields with the presence of
wells, drains, rivers, recharge, evapotranspiration and a variety of boundary
conditions. The model retrieves the heads and various flow and sink/source terms
saved by the model and automatically incorporates the specified boundary
conditions. |
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Analysis Features |
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MT3D99's modular structure is similar to MODFLOW and allows
simulation of sink/source mixing, chemical reactions, advection and dispersion
independently without reserving computer memory space for unused options.
Solution options include: |
- the implicit solution scheme
- the TVD solution scheme
- the method of characteristics (MOC) solution scheme
- the modified method of characteristics (MMOC) solution scheme
- the hybrid method of characteristics (HMOC) solution scheme
MT3D99
accommodates the following spatial discretization capabilities and mass
transport boundary conditions:
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- confined, unconfined and variably confined/unconfined aquifer layers;
- inclined model layers and variable cell thicknesses within the same layer;
- specified concentrations or mass flux boundaries; and
- the solute transport effects of external sources and sinks.
The chemical reactions
included in the model are: |
- equilibrium based linear or non-linear sorption
- non-equilibrium sorption
- first-order irreversible decay or biodegradation
- zero-order and mixed-order Monod kinetics
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Output Features |
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Post-processing program is also included with the
MT3D99 package to assist in the plotting of concentration
breakthrough curves and contour maps using
Surfer or other plotting packages. However, in order to best visualize the
results of MT3D, it is recommended that you utilize a graphical pre- and
post-processing software package like
Visual MODFLOW Premium.
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Deliverables and Documentation |
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MT3D99 comes with the executable programs ready to run on any PC.
The executable programs. are based on dynamic memory allocation to use all
extended memory that is available. The source code, written in standard
FORTRAN77, is included for implementation on Macintoshes, workstations, or
mainframes. A comprehensive users manual provides the model theory, equations
and verification with example problems.
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