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Environmental Modeling Community of Practice


The Multimedia, Multi-pathway, Multi-receptor Exposure and Risk Assessment (3MRA) technology provides the ability to conduct screening-level risk-based assessment of potential human and ecological health risks resulting from long term (chronic) exposure to HWIR chemicals released from land-based waste management units (WMUs) containing currently listed waste streams. The 3MRA system consists of a series of components within a system framework. The new modeling system, dubbed 3MRA technology, is envisioned as the foundation for eventually integrating other regulatory support decision tool needs anticipated in the future.

Current Version: 1.0
Release Date: July 2003
Development Status: General Release
Development Information: Release Notes - changes and known deficiencies

Source Code - uncompiled code and test packages
Operating System: Windows 98, NT, 2000, XP
Development Language: C++, Fortran
Intended Audience: Risk Assessor/Environmental Regulator
Key Words: multimedia, pathway, receptor, exposure, hazardous, waste, risk, assessment, HWIR
Related Web Sites: Description of 3MRA methodology
Text Files (ASCII Format)
File Name File Description
ABSTRACT.TXT Summary of functions, theory, and applicability.
README.TXT Important installation and usage information.
Download Files
File Type /
File Name /
Format /
File Description
Install /
Install_ 3MRA.EXE /
Installation Program /
372 MB
Setup file for version 1.0 of the 3MRA system including executables and databases. Use this for new installs. The system requires approximately 2GB of available hard drive space prior to installation.
Document /
3MRA_ Docs.EXE /
Self-extracting Zip /
46 MB
Five volume document set in Adobe Acrobat format including: 1) Modeling System & Science, 2) Data Collection, 3) Verification & Validation, 4) Uncertainty & Sensitivity Analysis, 5) Technology Design & Users Guide.
Document /
Example_ UA.EXE /
Self-extracting Zip /
226 MB
Example 3MRA Exit Level Uncertainty Analysis Results for 7 Chemicals. Includes Adobe SVG 3.0 Viewer and Microsoft Excel 97 Viewer. See UA_README.TXT for details. The example analysis requires approximately 1GB of available hard drive space prior to installation.
Install / Optional Coal River Mercury Study / Zip file / 1.78GB Coal River, W.Va. Hg sensitivity study software system installer, data, results and documentation.  iemWatersheds is a USGS HUC8 watershed modeling implementation of 3MRA/FRAMESv2 technology.
Document / Optional  Coal River Mercury Study Installation and Basic Operation Guide/ PDF / 300KB Coal River, W. Va. Hg sensitivity study software Installation/Operation guide.