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BIOSCREEN, Natural Attenuation Decision Support System

BIOSCREEN is a screening model that simulates remediation through natural attenuation of dissolved hydrocarbons at petroleum fuel release sites. The model is designed to simulate biodegradation by both aerobic and anaerobic reactions.

This screening tool will allow ground water remediation managers to identify sites where natural attenuation is most likely to be protective of human health and the environment. It will also allow regulators to carry out an independent assessment of treatability studies and remedial investigations that propose the use of natural attenuation.

This software, programmed in the Microsoft Excel spreadsheet environment and based on the Domenico analytical solute transport model, has the ability to simulate advection, dispersion, adsorption, and aerobic decay, as well as anaerobic reactions that have been shown to be the dominant biodegradation processes at many petroleum release sites. BIOSCREEN includes three different model types:

  • Solute transport without decay
  • Solute transport with biodegradation modeled as a first-order decay process (simple, lumped-parameter approach)
  • Solute transport with biodegradation modeled as an instantaneous biodegradation reaction with multiple soluble electron acceptors including dissolved oxygen, nitrate, and sulfate
Version 1.4
Release Date July 1997
Development Status General Release
Operating System Windows 95/98/NT, Excel

Minimum System Requirements

Any computer system capable of running Microsoft Excel version 5.0 or later will be able to run BIOSCREEN. However, because of the intensive floating point calculations used in the model, GSI recommends that the following minimum requirements be observed to ensure a minimum standard of performance:

Hardware Requirements

  • An Intel 486 CPU, operating at 50 MHz or faster
  • 8 MB Random Access Memory (16 MB or more will improve performance)
  • 1 MB free hard drive space (for BIOSCREEN only - Excel will require substantially more)

Software Requirements

  • BIOSCREEN is designed to be run under Microsoft Excel. Your system must have Excel version 5.0 or later properly installed.
  • BIOSCREEN has been tested on Excel version 5.0 for Windows on systems running Windows 3.1, Windows for Workgroups 3.11, Windows 95, and Windows NT Version 3.51; Excel version 7.0 on Windows 95 and Windows NT 3.51; and Excel 97 on Windows NT Version 3.51. BIOSCREEN runs equally well under all of these configurations. BIOSCREEN also runs well on Power Macintosh (and compatibles) running Excel version 5.0 for Macintosh.


BIOSCREEN Installation program, help files, and instructions (ZIP)(1 MB)

US EPA (1996) "BIOSCREEN, Natural Attenuation Decision Support System - User's Manual, Version 1.3 (PDF)."  (100 pp, 1.15 MB, About PDF) Publication No. EPA/600/R-96/087. August 1996

  1. Refer to the user's manual for further instructions.
  2. Go to the Windows Explorer and create a directory on the C drive named BIOSCRN (C:\BIOSCRN).
  3. Download the user’s manual and installation zip file to the new BIOSCRN directory.
  4. Extract the contents of the installation zip file inside the C:\BIOSCRN directory.
  5. To run BIOSCREEN after installation, start Microsoft Excel and open the BIOSCRN4.xls file. Loading from within Excel is preferred to double-clicking the file name in the file manager.