                                                           File:   UPDATE.TXT


                      PRZM 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 changes and/or addendums, undocumented or
otherwise, in the PRZM modeling system user manual files and other support
documentation since the publication of the user manual files for versions
2.00, 2.01 Beta, and/or 3.12 Beta.

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

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Changes Versions 2.00, 2.01 Beta
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Date: Wednesday, 12 October 1994.  Time: 14:54:33.
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For all changes/enhancements, refer to the "Model Enhancements and
Description of Bridge Programs for PRZM-2/HSPF and PRZM2/WASP Applications
--Addendum to the Users Manual for Release 2.0 of the PRZM-2 Model"
documentation file in WordPerfect (binary) format.  For further information,
refer to file PRZDOCAD.DOC.

Donigian, A.S., Jr., R.F. Carsel, J.C. Imhoff, and P.R. Hummel.  1994.  Model
Enhancements and Description of Bridge Programs for PRZM-2/HSPF and
PRZM2/WASP Applications--Addendum to the Users Manual for Release 2.0 of the
PRZM-2 Model.  U.S. Environmental Protection Agency, Athens GA.
(In Preparation).


Changes Version 3.12
~~~~~~~~~~~~~~~~~~~~
Date: Thursday, 26 February 1998.  Time: 13:14:37.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
No changes as of the above date.

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