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BIOCHLOR, Natural Attenuation Decision Support System

BIOCHLOR is a screening model that simulates remediation by natural attenuation of dissolved solvents at chlorinated solvent release sites. BIOCHLOR includes three different model types:

  • Solute transport without decay
  • Solute transport with biotransformation modeled as a sequential first-order decay process
  • Solute transport with biotransformation modeled as a sequential first-order decay process with two different reaction zones (i.e., each zone has a different set of rate coefficient values)

The software, programmed in the Microsoft Excel spreadsheet environment and based on the Domenico analytical solute transport model, has the ability to simulate one-dimensional advection, three-dimensional dispersion, linear adsorption, and biotransformation via reductive dechlorination (the dominant biotransformation process at most chlorinated solvent sites). Reductive dechlorination is assumed to occur under anaerobic conditions and dissolved solvent degradation is assumed to follow a sequential first-order decay process.

Specifications
Version 2.2
Release Date June 2002
Development Status General Release
Operating System Windows 95/98/NT, Excel

Minimum System Requirements

The BIOCHLOR model requires a computer system capable of running Microsoft Excel 97 or 2000 for Windows. Operation requires an IBM-compatible PC equipped with a Pentium II or later processor. A minimum of 64 MB of RAM is strongly recommended.

Downloads

Excel 2000 Version: User's manual, installation program, help files, and installation instructions(2 MB)

Excel 97 Version: User's manual, installation program, help files, and installation instructions(2 MB) Excel 97 Version: User's manual, installation program, help files, and installation instructions (EXE)

US EPA. (2000) "BIOCHLOR, Natural Attenuation Decision Support System - User's Manual, Version 1.0." (PDF) (54 pp, 541 K, About PDF)

US EPA. (2002) "BIOCHLOR, Natural Attenuation Decision Support System, Version 2.2, User's Manual Addendum." (PDF)