Pe4.pl Program Description
The program pe4.pl is a graphical interface (shell) used by the Environmental Fate and Effects Division (EFED) of the Office of Pesticides Programs (OPP) and the Pesticide Management Regulatory Agency (PMRA) of Health Canada to facilitate putting chemical- and use-specific input values into the proper positions in the PRZM input (inp) and the EXAMS chemical files. In order to run the shell, you need to have the official versions of PRZM and EXAMS on your computer and you still need to follow the latest guidance for selecting input parameters for environmental fate and transport models (http://www.epa.gov/oppefed1/models/water/input_guidance2_28_02.htm). Once the inputs have been entered, the interface creates the necessary input and run files, calls up PRZM and EXAMS, runs the programs, and creates the output files, just as the DOS versions do.
The interface was created using Perl and Tk, publicly available programming, and requires Perl Tk to run. The Pe4 Instructions Public guide provides instructions for setting up the shell and models on your computer, for running the shell, and for retrieving the outputs. The shell program code can be viewed in any text editor.
LIMITATIONS OF PE4.PL
In some more complex assessments, users will still need to operate PRZM and EXAMS through the DOS command line. EFED has identified the following known issues with the PE4.PL shell:
PE4.PL does not handle different application rates within the same scenario. For such cases, PE4.PL can still be used to generate a rough PRZM input file, and the user would be required to modify RECORD 16 manually and then run PRZM from a DOS command line.
PE4.PL does not have the capacity for modeling simultaneous formation and degradation kinetics of degradation products.
For modeling volatilization, PE4.PL requires an input value for ENPY even though the actual ENPY value is not used in simulation.
Output files should be given short names with less than 8 characters to allow consistent file management among different operating systems.
Questions concerning pe4.pl should be addressed to Dirk Young (firstname.lastname@example.org).