                                                           File:   UPDATE.TXT


                      LC50 Model System Update Notes


               Center for Exposure Assessment Modeling (CEAM)
     National Exposure Research Laboratory - Ecosystems Research Division
                  Office of Research and Development (ORD)
               U.S. Environmental Protection Agency (U.S. EPA)
                          960 College Station Road
                         Athens, Georgia 30605-2700

                                706/355-8400



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The following are explanations of scientific, application, and/or operational
changes and/or addendums, undocumented or otherwise, in the LC50 modeling
system user manual file and other support documentation since the publication
of the user manual file for version 1.00.

A brief explanation and/or example may be given for each change/enhancement.

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Changes Version 1.00
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Date: Monday, 11 January 1999.  Time: 08:43:26.
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First release.  No changes as of the above date.

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