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Environmental Modeling Community of Practice

MINTEQA2 Equilibrium Speciation Model

MINTEQA2 is a equilibrium speciation model that can be used to calculate the equilibrium composition of dilute aqueous solutions in the laboratory or in natural aqueous systems. The model is useful for calculating the equilibrium mass distribution among dissolved species, adsorbed species, and multiple solid phases under a variety of conditions including a gas phase with constant partial pressures. A comprehensive data base is included that is adequate for solving a broad range of problems without need for additional user-supplied equilibrium constants. The model employs a pre-defined set of components that includes free ions such as Na+ and neutral and charged complexes (e.g., H4SiO4, Cr(OH)2+). The data base of reactions is written in terms of these components as reactants. An ancillary program, PRODEFA2, serves as an interactive pre-processor to help produce the required MINTEQA2 input files.

Current Version: 4.03
Release Date: May 2006
Development Status: General Release
Development Information: Release Notes - changes and known deficiencies
Operating System: Windows 98, NT, 2000, XP
Development Language: FORTRAN
Intended Audience: Geochemist
Key Words: aquatic biology, assessment, compliance, metals, NPDES, permits, test/analysis
Related Web Sites: None Available
Text Files (ASCII Format)
File Name File Description
ABSTRACT.TXT Summary of functions, theory, and applicability.
README.TXT Important installation and usage information.

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Download Files
File Type /
File Name /
Format /
File Description
Install /
InstallShield Executable /
3.8 MB
Setup file for version 4.03 of the MINTEQA2 system. This file includes the MINTEQA2 software as well as the complete set of documentation. Refer to README.TXT for important installation instructions.
Document /
USERMANU.PDF MINTEQA2/PRODEFA2, A Geochemical Assessment Model for Environmental Systems: Version 3.0 User's Manual
Document /
SUPPLE1.PDF   MINTEQA2/PRODEFA2, A Geochemical Assessment Model for Environmental Systems: User Manual Supplement for Version 4.0
Document /
SUPPLE2.PDF   Diffuse-Layer Sorption Reactions for use in MINTEQA2 for HWIR Metals and Metalloids