1. General Model Information

Name: Surface Water Pesticide Exposure Estimation

Acronym: SURFEST

Main medium: terrestrial
Main subject: biogeochemistry, hydrology
Organization level: ecosystem
Type of model: not specified
Main application:
Keywords: pesticide, EEC, screening model


U. S. Environmental Protection Agency
Office of Pesticide Programs
401 M Street SW
Washington, DC 20460

Phone: 703-305-6725
FAX: 703-305-6309


R. David Jones, Ron Parker and Henry Nelson
Environmental Fate and Groundwater Branch,
Environmental Fate and Effects Division,
Office of Pesticide Programs,
U. S. Environmental Protection Agency


SurfEst is intended to be a user-friendly, screening model for calculation preliminary EEC's in support of the pesticide registration and reregistration process for use in ecological risk assessments.

Model Algorithms:
Spray Drift: ?
Runoff: SCS Curve Number method
Eroded Sediment: MUSLE
Pesticide Extraction from Soil: CREAMS method
Pond: analytical equation similar to stirred flow reactor
Stream: analytical equation for non-point source addition to plug-flow reactor

Output Parameters: Loadings to aquatic environments; pond and stream EEC's.

Processes Simulated:
Spray drift, transport of pesticide dissolved in runoff and adsorbed to eroded sediment; degradation in soil and water; transport and degradation in ponds and streams

Critical Assessment:
Strengths of Model: Simple, fast, easy to use, directed to a specific purpose.

Weaknesses of Model: Adequate for screening purposes; inadequate for other uses. Not validated.

Current Version No.: X1.0 (1992)

source of abstract: ACPA Modeldatabase (04/1998)

II. Technical Information

II.1 Executables:

Operating System(s): Minimal IBM PC or compatible with 640K RAM and MS-DOS 3.3 or higher. Current version fits on a single 360K floppy disk. Final version should fit on single 1.44 MB floppy disk.

II.2 Source-code:

Programming Language(s):

II.3 Manuals:


II.4 Data:

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

III.2.1 Input

III.2.2 Output

Output Flexibility:
Output is to the screen and consists of four values, spray drift loading, loading from the field runoff, pond EEC, and flowing water EEC. Pesticide and scenario input parameters can be saved to separate files.

Graphic Capability: None

IV. References

V. Further information in the World-Wide-Web

VI. Additional remarks

Last review of this document by: Juergen Bierwirth Fri Mar 18 12:10:24:10 MET 1998
Status of the document:
last modified by Tobias Gabele Wed Aug 21 21:44:50 CEST 2002

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