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Program Modifications & New Features in E-FAST Version 2.0

While conceptually similar to its predecessor, E-FAST Version 2.0 (EFAST2) has greatly expanded its help system and documentation, updated data sources, and improved data handling capabilities. Specific revisions include the following:

General Changes

  1. Physical-chemical property and fate information inputs for the chemical to be assessed are now consolidated at the start of E-FAST. Adsorption to wastewater treatment sludge is now included.

  2. Users can now select the directory where model results will be saved.

  3. Model results may be printed in either Corel WordPerfect or MS Word, also as individual screenshots.

  4. Default exposure values are now available for five children's age groups, instead of the previous two age groups.

  5. Potential Average Daily Dose (ADDPOT) and Average Daily Concentration (ADCPOT) values are not estimated in E-FAST V2.0 because averaging times for non-cancer chronic or subchronic effects vary by effect. In these cases, it is suggested that the averaging times should be determined on a case-by-case basis via communication between the exposure assessor and hazard assessor. When the appropriate averaging times have been determined, potential ADD and ADC values may be estimated by substituting those averaging times for the lifetime averaging time in the potential Lifetime Average Daily Dose (LADDPOT) and Lifetime Average Daily Concentration (LADCPOT) equations.

  6. Equation parameters are now standardized for similar applications in the different E-FAST V2.0 modules.

  7. Selected references that are not copyrighted are available as PDF files at this website.

  8. Appendix A lists definitions of physical-chemical and fate properties.

  9. The data used for assessments of releases to surface waters has been substantially revised to reflect the obsolescence of some sources. Appendix B describes the data framework for assessment of releases to surface waters.

  10. The Probabilistic Dilution Model (PDM), which is used in three of E-FAST's four modules, has been re-programmed to calculate the probability of exceedance directly, so it no longer requires the development and use of intermediate tables. Appendix C describes the statistical framework of PDM.

  11. The E-FAST V2.0 Documentation Manual is now accessible via the assistive technology reader.

General Population and Ecological Exposure Module
  1. Release information is now entered on separate water, land or air screens for each release scenario. If the percent adsorption of the chemical to wastewater treatment sludge was entered as a physical-chemical/fate input, EFAST2 will automatically calculate the amount of chemical in landfilled wastewater treatment sludge.

  2. Users may now search for endangered species in the vicinity of listed dischargers to surface water.

  3. Exposure estimates of chemicals in landfilled wastewater treatment sludge are now included in the exposure estimates of chemicals migrating to groundwater from landfills.

  4. In the landfill releases' ground water concentration estimation method, the "negligible to slow" migration factor value has been increased to better reflect the original documentation's conservative intent.

  5. Ambient air releases (stack or fugitive) are now assessed with a USEPA Office of Air model, SCREEN3, using generic default settings.

  6. Potential acute doses from releases to ambient air are now estimated in addition to annual averages.

  7. The October 2007 version corrects errors in the site-specific surface water facility database and errors associated with the Remarks section of the Data input page.

Consumer Exposure Module
  1. The time interval for the inhalation dose calculation has been shortened from 1 minute to 10 seconds. The shorter time interval more accurately estimates the integral calculation; a shorter time interval was not originally programmed into CEM because of the limitations of computing power at that time.

Down-the-Drain Module
  1. The default value for the number of years of product use has been increased from 30 years to 57 years to be consistent with the Consumer Exposure Module default for period of active usage of consumer products.

E-FAST Version 2.0 can be downloaded and installed using Download E-FAST V2.0


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