Evaluation of Three Watershed‐Scale Pesticide Environmental Transport and Fate Models 1

Abstract:  The U.S. Environmental Protection Agency (USEPA) Office of Pesticide Programs (OPP) has completed an evaluation of three watershed‐scale simulation models for potential use in Food Quality Protection Act pesticide drinking water exposure assessments. The evaluation may also guide OPP in identifying computer simulation tools that can be used in performing aquatic ecological exposure assessments. Models selected for evaluation were the Soil Water Assessment Tool (SWAT), the Nonpoint Source Model (NPSM), a modified version of the Hydrologic Simulation Program‐Fortran (HSPF), and the Pesticide Root Zone Model‐Riverine Water Quality (PRZM‐RIVWQ) model. Simulated concentrations of the pesticides atrazine, metolachlor, and trifluralin in surface water were compared with field data monitored in the Sugar Creek watershed of Indiana’s White River basin by the National Water Quality Assessment (NAWQA) program. The evaluation not only provided USEPA with experience in using watershed models for estimating pesticide concentration in flowing water but also led to the development of improved statistical techniques for assessing model accuracy. Further, it demonstrated the difficulty of representing spatially and temporally variable soil, weather, and pesticide applications with relatively infrequent, spatially fixed, point estimates. It also demonstrated the value of using monitoring and modeling as mutually supporting tools and pointed to the need to design monitoring programs that support modeling.

[1]  Probabilistic Aquatic Exposure Assessment for Pesticides I: Foundations , 2001 .

[2]  R. C. Moore,et al.  Transport of agrichemicals to ground and surface water in a small central indiana watershed , 1998 .

[3]  N. M. Idaikkadar,et al.  CHAPTER 10 – Census of Agriculture , 1979 .

[4]  Lee Carrubba.  Hydrologic modeling at the watershed scale using NPSM , 2000 .

[5]  D. Legates,et al.  Evaluating the use of “goodness‐of‐fit” Measures in hydrologic and hydroclimatic model validation , 1999 .

[6]  R. Parrish,et al.  A method for testing whether model predictions fall within a prescribed factor of true values, with an application to pesticide leaching , 1990 .

[7]  Description, instructions, and verification for Basinsoft, a computer program to quantify drainage- basin characteristics , 1996 .

[8]  W. Shiu,et al.  Illustrated handbook of physical-chemical properties and environmental fate for organic chemicals. Volume 5: pesticide chemicals. , 1992 .

[9]  Michael P. Schroeder,et al.  METHODS OF ANALYSIS BY THE U.S. GEOLOGICAL SURVEY NATIONAL WATER QUALITY LABORATORY- DETERMINATION OF ORGANONITROGEN HERBICIDES IN WATER BY SOLID-PHASE EXTRACTION AND CAPILLARY-COLUMN GAS CHROMATOGRAPHY/MASS * SPECTROMETRY WITH SELECTED-ION MONITORING , 1992 .

[10]  Walter J. Rawls,et al.  Predicting runoff from Rangeland Catchments: A comparison of two models , 1990 .

[11]  M. Burkhardt,et al.  Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of pesticides in water by Carbopak-B solid-phase extraction and high-preformance liquid chromatography , 1996 .

[12]  J. Arnold,et al.  VALIDATION OF THE SWAT MODEL ON A LARGE RWER BASIN WITH POINT AND NONPOINT SOURCES 1 , 2001 .

[13]  Charles G. Crawford,et al.  FACTORS AFFECTING PESTICIDE OCCURRENCE AND TRANSPORT IN A LARGE MIDWESTERN RIVER BASIN 1 , 2001 .

[14]  C. G. Crawford.  Trends in acetochlor concentrations in surface waters of the White River Basin, Indiana, 1994–96 , 1997 .

[15]  Nancy C. Hyland,et al.  Project Management and Redesign of the USDA Economics, Statistics, and Market Information System , 2005 .

[16]  C. G. Crawford.  Occurrence of pesticides in the White River, Indiana, 1991-95 , 1995 .

[17]  C. Ottow.  Natural Resources Conservation Service Web Site , 2000 .

[18]  R. Gilliom,et al.  Design of the National Water-Quality Assessment Program; occurrence and distribution of water-quality conditions , 1995 .

[19]  Lawrence A. Burns,et al.  Exposure Analysis Modeling System (EXAMS): User Manual and System Documentation , 2000 .

[20]  J. Nash,et al.  River flow forecasting through conceptual models part I — A discussion of principles☆ , 1970 .

[21]  Andrew P. Robinson,et al.  Model validation using equivalence tests , 2004 .

[22]  William Lane Austin,et al.  The Census of Agriculture , 1930 .

[23]  L. Burns,et al.  Transport and Transformation of Chemicals: A Perspective , 1980 .

[24]  L. R. Shelton.  FIELD GUIDE FOR COLLECTING AND PROCESSING STREAM-WATER SAMPLES FOR THE NATIONAL WATER-QUALITY ASSESSMENT PROGRAM , 1994 .

[25]  S. Bird,et al.  Evaluation of the AgDISP aerial spray algorithms in the AgDRIFT model , 2002, Environmental toxicology and chemistry.