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Environmental Modeling Community of Practice

Frequent Questions about Exposure Assessment Models

If you cannot find the answer to your question below, contact the EPA Center for Exposure Assessment Modeling (CEAM).

Question: I can't find the product that I need. Where else can I look?

Answer: If the software or data product is available through CEAM, it should be listed on the Modeling Products page of this Web site. You can also search this Web site using the Search feature at the top of any Exposure Assessment Models Web page. A list of related environmental modeling Web sites is also available.

Question: I am having trouble installing or running a model on my Windows 2000 or XP computer. Is the model incompatible with my operating system?

Answer: Some older models were compiled using Lahey Fortran 77 or Lahey Fortran 90. Models which utilized these compilers are incompatible with Windows 2000 and XP systems and must be run on Windows 95, 98, or NT operating systems. CEAM is in the process of updating affected models to address this problem.

Question: How can I receive the latest updates and announcements from CEAM? Is there a way that I can post announcements or questions to CEAM scientists and users?

Answer: By subscribing to the CEAM-USERS listserv system, you can send messages to other subscribers of the CEAM-USERS list to announce events like workshops, training sessions, and professional meetings or to ask and answer questions about exposure assessment modeling topics.

Question: The FEMWATER/LEWASTE model is no longer listed in the Groundwater Models page of the CEAM Web site. Is it still available?

Answer: FEMWATER/LEWASTE is no longer distributed or supported by CEAM. A variety of subsurface flow models are available from EPA's Center for Subsurface Modeling Support (CSMoS).

Question: Are CEAM software products available on disk?

Answer: Yes. Selected software and data files are available on disk upon request. Contact CEAM to request disk copies of software products.

Question: During the installation of a CEAM software product, an error message similar to the following is displayed: "Not ready reading drive x Abort, Retry, Fail?". How do I proceed with the installation?

Answer: Some older CEAM installation programs are designed to "poll" system resources to determine how many and what type of disk drives are available on the system. It is possible that the install program will find the CD ROM drive and attempt to include it in the list of available drives. The simple solution is to place any CD into the CD ROM drive then press the R, F, or Enter key.

Question: When I execute selected CEAM software products, strange, un-readable characters appear on or scroll across the screen. Can this be corrected?

Answer: Yes. Selected CEAM software products (i.e., HSPF, MINTEQ, MULTIMED, etc.) require that the device driver ANSI.SYS be loaded. The ANSI.SYS device driver file provides support for enhanced keyboard and screen capabilities. Instructions for loading ANSI.SYS, based on operating system, are listed below. CEAM recommends that you consult your local computer support personnel before implementing these changes.

  • DOS or Windows 3.1x: add the statement DEVICE=C:\DOS\ANSI.SYS to the CONFIG.SYS file;
  • Windows 95 or 98: add the statement DEVICE=C:\WINDOWS\COMMAND\ANSI.SYS to the CONFIG.SYS file;
  • Windows NT: add the statement DEVICE=%SystemRoot%\SYSTEM32\ANSI.SYS to the CONFIG.NT file.

The location of CONFIG.SYS, CONFIG.NT, and ANSI.SYS may differ from the examples shown above. Remember, the system must be shut-down and re-started before these changes will be activated.

Question: Where can I get information about environmental issues and potential environmental and human health risks caused by pollution?

Answer: The EPA’s Environmental Topics page provides information to help you, your family, and your community learn about and protect the environment.