Scientists in the Office of Pesticide Programs (OPP) in the Environmental Protection Agency (EPA) frequently use simulation models to predict pesticide concentrations in surface and ground water for use in both human health and aquatic ecological exposure assessments. Listed below are links to executable versions of each of the models currently in use, plus links to the documentation for these models.
More Useful Links
- Exposure Modeling Public Meeting - Information
- Guidance for Selecting Input Parameters in Modeling the Environmental Fate and Transport of Pesticides
- Positive Attributes and Desired Qualities for Models
- Development and Use of the Index Reservoir in Drinking Water Exposure Assessments
- Development and Use of Percent Cropped Area and Percent Turf Area Adjustment Factors in Drinking Water Exposure Assessments
- Finalization of Guidance on Incorporation of Water Treatment Effects on Pesticide Removal and Transformations in Drinking Water Exposure Assessments
- Golf Course Adjustment Factors for Modifying Estimated Drinking Water Concentrations and Estimated Environmental Concentrations Generated by Tier I (FIRST) and Tier II (PRZM/EXAMS) Models
- Guidance for Making Temperature Adjustments to Metabolism Inputs to EXAMS and PE5
- Relevant SAP Sessions
- Archived Documents
SWCC (Surface Water Concentration Calculator)
The Surface Water Concentration Calculator (SWCC) estimates pesticide concentrations in water bodies that result from pesticide applications to land. The SWCC is designed to simulate the environmental concentration of a pesticide in the water column and sediment and is used for regulatory purposes by the USEPA Office of Pesticide Programs (OPP). The SWCC uses PRZM version 5.0+ (PRZM5) and the Variable Volume Water Body Model (VVWM), replacing the older PE5 shell (last updated November 2006), which used PRZM3 (Carousel et al., 2005) and EXAMS (Burns, 2003). This updated model will improve users' interactions with the program and facilitate maintenance and operation of the software.
- Executable Installation
- SWCC (.msi executable file)
- Source Code
- Crop Scenarios
- SWCC (.zip compressed file)
PRZM (Pesticide Root Zone Model)
PRZM is a surface water model that simulates chemical movement in soil within and immediately below the plant root zone. PRZM is often linked with EXAMS to develop refined exposure assessments of pesticide concentrations in aquatic environments.
EXAMS (Exposure Analysis Modeling System)
EXAMS is a surface water model that evaluates the fate, transport, and exposure concentration of pesticides. EXAMS is frequently linked with PRZM to develop refined exposure assessments of pesticide concentrations in aquatic environments.
PE Version 5.0
Approved Model Suite
- PE 5.0 User's Manual | Microsoft® Office Word Version (8 pp, 88 KB)
- Standard Crop Scenario Metadata
- Nonstandard Crop Scenario Metadata
KABAM Version 1.0 (Kow (based) Aquatic BioAccumulation Model)
KABAM is used to estimate potential bioaccumulation of hydrophobic organic pesticides in freshwater aquatic food webs and subsequent risks to mammals and birds via consumption of contaminated aquatic prey.
FIRST (FQPA Index Reservoir Screening Tool)
FIRST is a surface water model that is used to assess exposure to pesticides in drinking water.
FIRST Version 1.0
FIRST Version 1.1.1
- Executable firstv1_1_1.exe (576 kb)
- Source Code (Fortran 77) first_version1_1_1.for (46 kb)
- Description | Microsoft® Office Word Version (9 pp, 67 KB)
- Users Manual | Microsoft® Office Word Version (13 pp, 101 KB)
GENEEC2 (GENeric Estimated Environmental Concentration)
GENEEC is a surface water model that is used to assess exposure of pesticides to aquatic organisms and the environment.
- Executable geneec2.exe (80 kb)
- Source Code (Fortran 77) geneec2.for (60 kb)
- Users Manual
Tier I Rice Model
Tier I Rice Model is an aquatic model used to estimate surface water exposure from the use of pesticides in rice paddies.
PFAM (Pesticides in Flooded Application Model)
PFAM is an aquatic model used to estimate surface water exposure from the use of pesticides in flooded fields. In comparison to the current Tier 1 rice model, PFAM allows for more advanced evaluation of pesticide use on flooded agricultural areas such as rice paddies and cranberry bogs. The advanced capabilities of PFAM include accounting for water and pest management practices and for degradation in soil and aquatic environments, as well as for post processing of discharged paddy waters to a stream, index reservoir, farm pond, or other user-defined receiving water.
- Executable PFAMinstall.msi (1.5MB)
SCI-GROW (Screening Concentration In GROund Water)
SCIGROW is an aquatic model used to estimate pesticide concentrations in ground water.
- Executable sg23.exe (336 kb)
- Source Code (Fortran 90) scigrow.f90 (5 kb)
- User's Manual for Version 2.3 is under development
- Version 1.07 Executable PRZMGW.msi (1.4MB)
- Guidance for Using PRZM-GW in Drinking Water Exposure Assessments
- Guidance for Selecting Input Parameters for Modeling Pesticide Concentrations in Groundwater Using the Pesticide Root Zone Model
- Model and Scenario Development Guidance for Estimating Pesticide Concentrations in Groundwater Using the Pesticide Root Zone Model
- Version 1.07 Scenarios (.zip 106 Kb)
- DRAFT Final Report. Identification and Evaluation of Existing Models for Estimating Environmental Pesticide Transport to Groundwater. A North American Free Trade Agreement (NAFTA) Project.
AGDISP (version 8.26) is a "first-principles" science-based model that predicts spray drift from application sites. The model was developed by the USDA Forest Service. AGDISP was designed to optimize agricultural spraying operations and has detailed algorithms for characterizing the release, dispersion, and deposition over and downwind of the application area. This model can be used in estimating downwind deposition of spray drift from aerial and ground boom applications. In addition, it can be used in estimating downwind deposition of spray drift from forestry and adulticide/mosquitocide applications. The research version of AGDISP model can be obtained from Dr. Harold W. Thistle, USDA Forest Service.
- AGDISP 8.26.piz (6.74 MB zipfile)
AgDRIFT(version 2.1.1), a modified version of the AGricultural DISPersal (AGDISP) model developed by the US Forest Service, was created under a Cooperative Research and Development Agreement between the EPA, the US Department of Agriculture's Forest Service, and the Spray Drift Task Force. The AgDRIFT model has the capability to assess a variety of spray drift conditions from agricultural applications and off-site deposition of liquid formulation of pesticides. This model can be used in estimating downwind deposition of spray drift from aerial, ground boom and orchard/vineyard airblast applications.
- AgDRIFT 2.1.1.piz (11.7 MB zipfile)