Description System Requirements Downloads: Installation and Start-Up Technical Support

Description  Back to Top

MT3D is a 3D solute transport model for simulation of advection, dispersion, and chemical reactions of dissolved constituents in ground-water systems. The model uses a modular structure similar to that implemented in MODFLOW. The modular structure makes it possible to independently simulate advection, dispersion, sink/source mixing, and chemical reactions without reserving computer memory space for unused options. MT3D uses a mixed Eulerian-Lagrangian approach to solve the three-dimensional advective-dispersive-reactive equation, in three basic options: the method of characteristics (MOC), the modified method of characteristics (MMOC), and a hybrid of these two methods (HMOC). This approach combines the strength of the MOC for eliminating numerical dispersion with the computational efficiency of the MMOC. The availability of both MOC and MMOC options, and their selective use based on an automatic adaptive procedure under the HMOC option, make MT3D uniquely suitable for a wide range of field problems. MT3D is intended for use with any block-centered finite-difference flow model such as MODFLOW and is based on the assumption that changes in the concentration field will not measurably affect the flow field. This allows the user to independently construct and calibrate a flow model. MT3D retrieves the hydraulic heads and the various flow and source/sink terms saved by the flow model, automatically incorporating the specified hydrologic boundary conditions. Although the MT3D documentation describes the use of MT3D in conjunction with MODFLOW, the transport model can be linked to any other block-centered finite-difference flow model. MT3D can be used to simulate changes in concentration of single-species miscible contaminants in ground-water considering advection, dispersion, and some simple chemical reactions. The chemical reactions included in the model are equilibrium-controlled linear or non-linear sorption and first-order irreversible decay or biodegradation.

Minimum System Requirements  Back to Top

This system was designed to run under DOS (Disk Operating System) on an IBM PC, XT, AT, PS2, or compatible computer. Graphics capability is not required, but is highly recommended, as most programs will produce graphics output. Graphics support is provided for the Hercules graphics card, the Color Graphics Adapter (CGA), and the Enhanced Graphics Adapter (EGA). At least 512 kilobytes (Kb) of random access memory (RAM) is required, but 640 Kb is recommended. An arithmetic co-processor chip is strongly recommended due to the computationally intensive nature of the programs, but is not required for use. Programs may be run from floppy diskette, however, a fixed disk is required to use the programs from the system menu. The system storage requirement is approximately three megabytes.

Installation and Start-Up  Back to Top

Getting Started:

You will need unzipping (compression) software to uncompress ZIP files. If you need to load compression software on your computer, free software is available for download on the internet at the following sites:

http://www.pkunzip.com -  PKUNZIP home page
http://www.cdrom.com/pub/infozip - InfoZip Wiz

You will need Adobe Acrobat Reader to view the documentation (PDF) files. The Reader is available free from Adobe at the sites below:

http://www.adobe.com - Adobe Reader download page
ftp://ftp.adobe.com - Adobe anonymous ftp home page

Installing the Program:

Five files are available for download

• mt3d1.zip (433 Kb): Program and installation files
• mt3d2.zip (1,067 Kb): Program and installation files
• pmod_ada.zip (120 Kb): User's Manual
• pmodada2.zip (136 Kb): Program and installation files
• mt3d.pdf (1,868 Kb): User's Manual

To download and install MT3D the following procedures MUST be followed:

1. View the online User’s Manual (MT3D.PDF) file for further installation instructions.
2. Download the 2 files MT3D1.ZIP and MT3D2.ZIP
3. After the downloads have completed, unzip MT3D1.ZIP to a blank formatted 3.5 high-density diskette labeled "MT3D Disk 1".
4. Unzip MT3D2.ZIP to a blank formatted 3.5 diskette labeled "MT3D Disk 2".
5. Put the disk labeled "MT3D Disk 1" into the 3.5" drive.
6. At the DOS prompt, change drives to your 3.5" drive
7. Type INSTALL.
8. Follow the on-screen directions and see the User's Manual.

Installing the Post Processors:  Back to Top

Post Processor #1: 200 x 200

1. Save the file to the same directory as the MT3D executible file.
2. Unzip the files to the same directory.
3. Start the post processor by running the executable program pmod_ada.exe.

Post Processor #2: 500 x 500

1. Save the file to the same directory as the MT3D executible file.
2. Unzip the files to the same directory.
3. Start the post processor by running the executable program pmodada2.exe.
   
   The post processors for MODFLOW were originally developed in the public domain at Arizona Department of Water Resources. The processor creates 2D head/drawdown ASCII files using the binary output from MODFLOW. This version of the software is compatible with the output file from the MODFLOW distributed with MT3D by Center for Subsurface Modeling Support (CSMoS).
   
   Please note that this program neglects any head value equal to zero and greater than 9999. Therefore, caution should be used if you are simulating water levels near sea level or in high elevation mountainous regions. The purpose for neglecting heads equal to 9999 was to set the flag HNOFLO to this value.
   
   This file can then be used in SURFER or any other software for contour plots.

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