The Pesticide Root Zone Model Groundwater (PRZM-GW) was developed as a regulatory model to estimate pesticide concentrations in vulnerable groundwater sources as part of a North American Free Trade Agreement (NAFTA) to develop a harmonized groundwater modeling protocol. The Office of Pesticide Programs implemented the use of PRZM-GW as an exposure model in 2012.
This guidance describes the groundwater conceptual model and the methods for developing scenarios for the PRZM-GW model.
You will need Adobe Reader to view some of the files on this page. See EPA’s About PDF page to learn more.-
Model and Scenario Development Guidance for Estimating Pesticide Concentrations in Groundwater Using the Pesticide Root Zone Model (PDF)(21 pp, 299 K,
October 15, 2012)
This guidance describes the methods for developing scenarios for the PRZM-GW model. PRZM-GW is an implementation of the Pesticide Root Zone Model (Suarez, 2006) in which a pesticide moves downward into an aquifer according to the NAFTA conceptual model. Scenarios are the subset of input parameters that describe the spatial characteristics of the PRZM-GW parameters. These include weather, soil, and crop characteristics.