Agricultural Chemicals

Occurrence and fate of chemicals used for agriculture

Adams, C.D., Randtke, S.J., Thurman, E.M., and Hulsey, R.A., 1990,

Atrazine and its degradation products in soil and ground water, and the effectiveness of water-treatment processes for their removal, in University of Kansas Environmental 40th Annual Conference, Proceedings, Lawrence, Kan., February 7, 1990: p. 1-24.

Adams, C.D., and Thurman, E.M., 1991,

Formation and transport of deethylatrazine in the soil and vadose zone: Journal of Environmental Quality, v. 30, p. 540-547.

Aga, D.S., 1995,

Analytical applications of immunoassays in environmental and agricultural chemistry--study of the fate and transport of herbicides: Lawrence, University of Kansas, Department of Chemistry, Ph.D. thesis, 220 p.

Aga, D.S., and Thurman, E.M., 2001,

Formation and transport of the sulfonic acid metabolites of alachlor and metolachlor in soil: Environmental Science and Technology, v. 35, no. 12, p. 2455-2460, doi:10.1021/es991264s.

Aga, D.S., and Thurman, E.M., 1997,

Environmental Immunoassays--Alternative techniques for soil and water analysis, in Aga, D.S., and Thurman, E.M., eds., Immunochemical technology for environmental applications: Washington D.C., American Chemical Society ACS Symposium Series 657, p. 1-20.

Aga, D.S., and Thurman, E.M., 1995,

Application of solid-phase extraction (SPE) for ultratrace analysis of herbicides in water and soil by enzyme-linked immunosorbent assay (ELISA), in Kurtz, D.A., Skerritt, J.H., and Stanker, L., eds., Agrochemical Immunoanalysis-93: Arlington, Va., AOAC International, p. 317.

Aga, D.S., and Thurman, E.M., 1993,

Coupling solid-phase extraction and enzyme-linked immunosorbent assay for ultratrace determination of herbicides in pristine water: Analytical Chemistry, v. 65, no. 20, p. 2894-2898.

Aga, D.S., Thurman, E.M., and Pomes, M.L., 1996,

Measurement of concentrations of alachlor and its ethanesulfonic acid metabolite in water by solid-phase extraction and enzyme-linked immunosorbent assay, in Morganwalp, D.W., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water-Resources Investigations Report 94-4015, v. 1, p. 385-392.

Aga, D.S., Thurman, E.M., and Pomes, M.L., 1994,

Determination of alachlor and its sulfonic acid metabolite in water by solid-phase extraction and enzyme-linked immunosorbent assay: Analytical Chemistry, v. 66, no. 9, p. 1495-1499.

Aga, D.S., Thurman, E.M., Yockel, M.E., Zimmerman, L.R., and Williams, T.D., 1996,

Identification of a new sulfonic acid metabolite of metolachlor in soil: Environmental Science and Technology, v. 30, no. 2, p. 592-597, doi:10.1021/es9503600.

Aga, D.S., and Thurman, E.M., eds., 1997,

Immunochemical technology for environmental applications: American Chemical Society ACS Symposium Series 657, 396 p.

Alberts, E.E., Prato, A.A., Blevins, D.W., and Killpack, S.C., 1995,

Research need and plans of the Missouri MSEA project, in 5th Annual Missouri Water Quality Conference Proceedings, Columbia, Missouri, February 2, 1995: University of Missouri, p. 172-176.

Alberts, E.E., Prato, T., Kitchen, N.K., and Blevins, D.W., 1993,

Research and education to improve surface and ground water quality of a claypan soil, in Agricultural Research to Protect Water Quality--Proceedings of the Conference, Minneapolis, Minnesota, February 21-24, 1993: Ankeny, Iowa, Soil and Water Conservation Society, p. 21-38.

Anderholm, S.K., 1986,

Reconnaissance of hydrology, land use, ground-water chemistry and effects of land use on ground-water chemistry in the Albuquerque-Belen basin, New Mexico: U.S. Geological Survey Water-Resources Investigations Report 86-4174, 37 p.

Anderson, J.L., Dowdy, R.H., and Delin, G.N., 1991,

Ground water impacts from irrigated ridge-tillage, in Ritter, W.F., ed., National Conference on Irrigation and Drainage Engineering, American Society of Civil Engineers, Honolulu, Hawaii, July 23-26, 1991: p. 604-610.

Anderson, J.L., Dowdy, R.H., Lamb, J.A., Delin, G.N., Knighton, R., Clay, D., and Lowery, B., 1993,

Northern Cornbelt Sand Plains Management Systems Evaluation Area, in Agricultural Research to Protect Water Quality--Proceedings of the Conference, Minneapolis, Minnesota, February 21-24, 1993: Ankeny, Iowa, Soil and Water Conservation Society, p. 39-47.

Antweiler, R.C., Goolsby, D.A., and Taylor, H.E., 1996,

Nutrients in the Mississippi River, 1987-92, in Meade, R.H., ed., Contaminants in the Mississippi River: U.S. Geological Survey Circular 1133, p. 73-85.

Arai, Y., Lanzirotti, A., Sutton, S., Davis, J.A., and Sparks, D.L., 2003,

Arsenic speciation and reactivity in poultry litter: Environmental Science and Technology, v. 37, p. 4083-4090, doi:10.1021/es0340580.

Asmussen, L.E., and Smith, C.N., 1990,

Study design to investigation and simulate agrichemical movement and fate in ground-water recharge, in Nash, R.G., and Leslie, A.R., eds., Ground water research and sampling design: Washington, D.C., American Chemical Society ACS Symposium Series 465, p. 150-164.

Aulenbach, B.T., Buxton, H.T., Battaglin, W.A., and Coupe, R.H., 2007,

Streamflow and nutrient fluxes of the Mississippi-Atchafalaya River Basin and subbasins for the period of record through 2005: U.S. Geological Survey Open-File Report 2007-1080 (Available On Line Only).

Bachman, L.J., Krantz, D.E., and Böhlke, J.K., 2002,

Hydrogeologic framework, ground-water geochemistry and assessment of nitrogen yield from base flow in two agricultural watersheds, Kent County, Maryland: U.S. Environmental Protection Agency EPA/600/R-02/008, 93 p.

Bair, E.S., Springer, A.E., and Finton, C.D., 1993,

Hydrogeologic characterization of the Ohio MSEA, in Watermeir, N.L., ed., Ohio Buried Valley Aquifer Management Systems Evaluation Area Colloquium, October 27, 1993: Columbus, Ohio State University, p. 17-22.

Baker, N.T., Stone, W.W., Wilson, J.T., and Meyer, M.T., 2006,

Occurrence and transport of agricultural chemicals in Leary Weber Ditch Basin, Hancock County, Indiana, 2003-04: U.S. Geological Survey Scientific Investigations Report 2006-5251, 44 p.

Barringer, T.A., Dunn, D., Battaglin, W., and Vowinkel, E.F., 1990,

Problems and methods involved in relating land use to ground-water quality: Water Resources Bulletin, v. 26, no. 1, p. 1-9, doi:10.1111/j.1752-1688.1990.tb01345.x.

Barton, C., Vowinkel, E.F., and Nawyn, J.P., 1987,

Preliminary assessment of water quality and its relation to hydrogeology and land use--Potomac-Raritan-Magothy aquifer system, New Jersey: U.S. Geological Survey Water-Resources Investigations Report 87-4023, 79 p.

Bastian, K.C., Thurman, E.M., and Rebich, R.A., 1998,

Comparison of enzyme-linked immunoassay with gas chromatography/mass spectrometry for analysis of the cotton herbicide fluometuron, in 28th Mississippi Water Resources Conference, Proceedings, Raymond, Mississippi, April 7-8, 1998: Starkville, Miss., Mississippi State University, p. 45-55.

Battaglin, W., Drewes, J., Bruce, B., and McHugh, M., 2007,

Contaminants of emerging concern in the environment: Water Resources Impact, v. 9, no. 3, p. 3-4.

Battaglin, W.A., 2002,

Using ratios of atrazine transformation products to atrazine to determine its source in Midwestern streams, in Kenny, J., ed., Ground Water/Surface Water Interactions, AWRA Summer Specialty Conference Proceedings, Middleburg, Virginia: American Water Resources Association, TPS-02-2, p. 213-218.

Battaglin, W.A., 1993,

Use of volume modelling techniques to estimate agricultural chemical mass in groundwater, Minnesota, USA: International Association of Hydrological Sciences, IAHS Publication No. 211, 591-599 p.

Battaglin, W.A., 1992,

Estimation of agricultural chemical mass in ground water by volume modeling techniques: Golden, Colorado School of Mines, M.E. thesis, ER-4284, 157 p.

Battaglin, W.A., and Fairchild, J., 2002,

Potential toxicity of pesticides measured in midwestern streams to aquatic organisms: Water Science and Technology, v. 45, no. 9, p. 95-103.

Battaglin, W.A., Furlong, E.T., and Burkhardt, M.R., 2001,

Concentration of selected sulfonylurea, sulfonamide, and imadazolinone herbicides, other pesticides, and nutrients in 71 streams, 5 reservoir outflows, and 25 wells in the midwestern United States, 1998: U.S. Geological Survey Water-Resources Investigations Report 00-4225, 123 p.

Battaglin, W.A., Furlong, E.T., Burkhardt, M.R., and Peter, C.J., 2000,

Occurrence of sulfonylurea, sulfonamide, imidazolinone, and other herbicides in rivers, reservoirs and ground water in the Midwestern United States, 1998: The Science of the Total Environment, v. 248, no. 2-3, p. 123-133, doi:10.1016/S0048-9697(99)00536-7.

Battaglin, W.A., Furlong, E.T., Burkhardt, M.R., and Peter, C.J., 1999,

Occurrence of sulfonylurea, imidazolinone, and other herbicides in midwestern rivers, reservoirs, and ground water, 1998, in Morganwalp, D.W., and Buxton, H.T., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting, Charleston, South Carolina, March 8-12, 1999--Volume 2 of 3--Contamination of Hydrologic Systems and Related Ecosystems: U.S. Geological Survey Water-Resources Investigations Report 99-4018B, p. 215-225.

Battaglin, W.A., Furlong, E.T., and Peter, C.J., 1998,

A reconnaissance for new, low-application rate herbicides in surface and ground water in the Midwestern United States, in Proceedings of the National Water Quality Monitoring Council (NWQMC) National Conference, Monitoring--Critical Foundations to Protect Our Waters, Reno, Nevada, July 7-9, 1998: Washington, D.C., U.S. Environmental Protection Agency, p. 245-256.

Battaglin, W.A., Furlong, E.T., and Peter, C.J., 1998,

A reconnaissance for sulfonylurea herbicides in waters of the Midwestern USA: An example of collaboration between the public and private sectors: U.S. Geological Survey Fact Sheet FS-046-98, 4 p.

Battaglin, W.A., and Goolsby, D.A., 2000,

Herbicide concentrations in Midwest reservoirs (plus a self-study examination to earn continuing education credit): Crop Decisions, v. 42, no. 3, p. 5-8.

Battaglin, W.A., and Goolsby, D.A., 1999,

Are shifts in herbicide use reflected in concentration changes in midwestern rivers?: Environmental Science and Technology, v. 33, no. 17, p. 2917-2925, doi:10.1021/es9900149.

Battaglin, W.A., and Goolsby, D.A., 1998,

Regression models of herbicide concentrations in outflow from reservoirs in the midwestern USA, 1992-1993: Journal of the American Water Resources Association, v. 34, no. 6, p. 1369-1390, doi:10.1111/j.1752-1688.1998.tb05438.x.

Battaglin, W.A., and Goolsby, D.A., 1997,

Statistical modeling of agricultural chemical occurrence in midwestern rivers: Journal of Hydrology, v. 196, no. 1-4, p. 1-25, doi:10.1016/S0022-1694(97)00011-5.

Battaglin, W.A., and Goolsby, D.A., 1996,

Using GIS and logistic regression to estimate agricultural chemical concentrations in rivers of the midwestern USA, in Kovar, K., and Nachtnebel, H., eds., Application of Geographic Information Systems in Hydrology and Water Resources Management--Proceedings of HydroGIS'96 meeting, Vienna, Austria, April, 1996: International Association of Hydrological Sciences IAHS Publication No. 235, p. 253-260.

Battaglin, W.A., and Goolsby, D.A., 1996,

Using GIS and regression to estimate annual herbicide concentrations in outflow from reservoirs in the midwestern USA, 1992-93, in AWRA Symposium on GIS and Water Resources, Ft. Lauderdale, FL, September 22-26, 1996: American Water Resources Association.

Battaglin, W.A., and Goolsby, D.A., 1996,

Using GIS and regression to estimate annual herbicide concentrations in outflow from reservoirs in the midwestern USA, 1992-93, in Hallam, C.A., Salisbury, H.M., Lanfear, K.J., and Battaglin, W.A., eds., GIS and Water Resources--Proceedings of the American Water Resources Association: American Water Resources Association Technical Publication Series TPS-96-3, p. 89-98.

Battaglin, W.A., and Goolsby, D.A., 1995,

Spatial data in Geographic Information System format on agricultural chemical use, land use, and cropping practices in the United States: U.S. Geological Survey Open-File Report 94-4176, 87 p.

Battaglin, W.A., and Goolsby, D.A., 1994,

Relations between herbicide use and annual transport of herbicides in midwestern rivers, 1991-92, in Weigmann, D.L., ed., New Directions in Pesticide Research Development, Management, and Policy--Proceedings of the Fourth National Conference, on Pesticides, Richmond, Va., November 1-3, 1993: p. 711-723.

Battaglin, W.A., Goolsby, D.A., and Coupe, R., 1993,

Annual use and transport of agricultural chemicals in the Mississippi River, 1991-92, in Goolsby, D.A., Boyer, L.L., and Mallard, G.E., eds., Selected papers on agricultural chemicals in water resources of the Midcontinental United States: U.S. Geological Survey Open-File Report 93-418, p. 26-40.

Battaglin, W.A., Goolsby, D.A., and Coupe, R.H., 1996,

Annual use and transport of agricultural chemicals in the Mississippi River, 1991-92, in Morganwalp, D.W., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water-Resources Investigations Report 94-4015, v. 1, p. 429-440.

Battaglin, W.A., Goolsby, D.A., and Mueller, D.K., 1994,

Relations between use, concentration, and transport of agricultural chemicals in the Mississippi River basin, in Marston, R.A., and Hasfurther, V.R., eds., Effects of Human-induced Changes on Hydrologic System--Proceedings of the American Water Resources Association summer symposium, Jackson Hole, Wyoming, June 26-29, 1994: p. 1073-1086.

Battaglin, W.A., and Hay, L.E., 1996,

Effects of sampling strategies on estimates of annual mean herbicide concentrations in midwestern rivers: Environmental Science and Technology, v. 30, no. 3, p. 889-896, doi:10.1021/es950351r.

Battaglin, W.A., Kendall, C., Chang, C.C.Y., Silva, S.R., and Campbell, D.H., 2001,

Chemical and isotopic evidence of nitrogen transformation in the Mississippi River, 1997-98: Hydrological Processes, v. 15, no. 7, p. 1285-1300, doi:10.1002/hyp.214.

Battaglin, W.A., Kendall, C., Chang, C.C.Y., Silva, S.R., and Campbell, D.H., 2001,

Isotopic and chemical composition of inorganic and organic water-quality samples from the Mississippi River Basin, 1997-98: U.S. Geological Survey Water-Resources Investigations Report 01-4095, 57 p.

Battaglin, W.A., Kendall, C., Goolsby, D.A., and Boyer, L.L., 1997,

Plan of study to determine if the isotopic ratios ?15N and ?18O can reveal the sources of nitrate discharged by the Mississippi River into the Gulf of Mexico: U.S. Geological Survey Open-File Report 97-230, 18 p.

Battaglin, W.A., Kolpin, D.W., Scribner, E.A., Kuivila, K.M., and Sandstrom, M.W., 2005,

Glyphasate, other herbicides, and transformation products in midwestern streams, 2002: Journal of the American Water Resources Association, v. 41, no. 2, p. 323-332, doi:10.1111/j.1752-1688.2005.tb03738.x

Battaglin, W.A., Kuivila, K., Winton, K., and Meyer, M., 2008,

Occurrence of chlorothalonil, its transformation products, and selected other pesticides in Texas and Oklahoma streams, 2003-2004: U.S. Geological Survey Scientific Investigations Report 2008–5016, 9 p.

Battaglin, W.A., Thurman, E.M., Kalkhoff, S.J., and Porter, S.D., 2003,

Herbicides and transformation products in surface waters of the midwestern United States: Journal of the American Water Resources Association, v. 39, no. 4, p. 743-756, doi:10.1111/j.1752-1688.2003.tb04402.x.

Battaglin, W.A., Thurman, E.M., Kolpin, D.W., Scribner, E.A., Sandstrom, M.W., and Kuivila, K.M., 2003,

Work plan for determining the occurrence of glyphosate, its transformation product AMPA, other herbicide compounds, and antibiotics in midwestern United States streams, 2002: U.S. Geological Survey Open-File Report 03-69, 18 p.

Battaglin, W.A., Ulery, R., Welborn, T., and Winterstein, T., 2003,

Susceptibility of surface water in Texas to nonpoint source pesticide contamination, in Kolpin, D., and Williams, J.W., eds., AWRA 2003 Spring Specialty Conference: Agricultural Hydrology and Water Quality, Kansas City, Missouri, May 12-14, 2003: American Water Resources Association, p. on CD-ROM, TPS-03-1, ISBN:1-882132-61-0.

Battaglin, W.A., Ulery, R.L., Winterstein, T., and Welborn, T., 2003,

Estimating the susceptibility of surface water in Texas to nonpoint-source contamination by use of logistic regression modeling: U.S. Geological Survey Water-Resources Investigations Report 03-4205, 24 p.

Bergamaschi, B.A., Baston, D.S., Crepeau, K.L., and Kuivila, K.M., 1999,

Determination of pesticides associated with suspended sediments in the San Joaquin River, California, USA, using gas-chromatography-ion trap mass spectrometry: Toxicological and Environmental Chemistry, v. 69, p. 305-319.

Bergamaschi, B.A., Kuivila, K.M., and Fram, M.S., 2001,

Pesticides associated with suspended sediments entering San Francisco Bay following the first major storm of water year 1996: Estuaries, v. 24, no. 3, p. 368-380.

Bergamaschi, B.A., Kuivila, K.M., and Fram, M.S., 1999,

Pesticides associated with suspended sediments in the San Francisco Bay during the first flush, December 1995, in Morganwalp, D.W., and Buxton, H.T., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting, Charleston, South Carolina, March 8-12, 1999--Volume 2 of 3--Contamination of Hydrologic Systems and Related Ecosystems: U.S. Geological Survey Water-Resources Investigations Report 99-4018B, p. 23-33.

Blevins, D.W., 1991,

Planned studies of movement of nitrogen species and herbicides on claypan soils at the Management Systems Evaluation Area, Missouri, in Mallard, G.E., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Monterey, California, March 11-15, 1991: U.S. Geological Survey Water-Resources Investigations Report 91-4034, p. 240-242.

Blevins, D.W., Wilkison, D.H., Kelly, B.P., and Silva, S.R., 1996,

Movement of nitrate fertilizer to glacial till and runoff from a claypan soil: Journal of Environmental Quality, v. 25, no. 3, p. 582-593.

Blevins, D.W., Wilkison, D.H., Silva, S.R., and Kelly, B.P., 1996,

Use of 15N to trace movement of nitrogen fertilizer at a field plot, in Morganwalp, D.W., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water-Resources Investigations Report 94-4015, v. 1, p. 401-409.

Blickwedel, R.S., and Wood, C.R., 1989,

Relation of ground-water quality to land use in the Philadelphia, Pennsylvania--Camden, New Jersey area: U.S. Geological Survey Water-Resources Investigations Report 88-4211, 58 p.

Böhlke, J.K., and Denver, J.M., 1995,

Combined use of groundwater dating, chemical, and isotopic analyses to resolve the history and fate of nitrate contamination in two agricultural watersheds, Atlantic coastal plain, Maryland: Water Resources Research, v. 31, p. 2319-2339.

Böhlke, J.K., and Horan, M., 2000,

Strontium isotope geochemistry of ground waters and streams affected by agriculture, Locust Grove, Maryland: Applied Geochemistry, v. 15, p. 599-609.

Böhlke, J.K., Wanty, R., Tuttle, M., Delin, G., and Landon, M., 2002,

Denitrification in the recharge area and discharge area of a transient agricultural nitrate plume in a glacial outwash sand aquifer, Minnesota: Water Resources Research, v. 38, no. 7, p. 26.

Bosch, D.D., Leonard, R.A., and Hubbard, R.K., 1996,

Unsaturated zone transport at the Plains, Georgia field site, in Morganwalp, D.W., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water-Resources Investigations Report 94-4015, v. 2, p. 965-969.

Boxall, A.B.A., Sinclair, C.J., Fenner, K., Kolpin, D., and Maund, S.J., 2004,

When synthetic chemicals degrade in the environment--What are the absolute fate, effects, and potential risks to humans and the ecosystem?: Environmental Science and Technology, v. 38, no. 19, p. 368A-375A.

Boxall, A.B.A., Sinclair, C.J., and Kolpin, D.W., 2006,

Potential risks of pesticide degradates to aquatic life, in Gilliom, R.J., and others, eds., Pesticides in the nation's streams and ground water, 1992-2001: U.S. Geological Survey Circular 1291, p. 81-86.

Boyd, R.A., 1999,

Herbicides and herbicide degradates in shallow ground water and the Cedar River near a municipal well field, Cedar Rapids, Iowa, in Morganwalp, D.W., and Buxton, H.T., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting, Charleston, South Carolina, March 8-12, 1999--Volume 2 of 3--Contamination of Hydrologic Systems and Related Ecosystems: U.S. Geological Survey Water-Resources Investigations Report 99-4018B, p. 289-300.

Bradley, P.M., Chapelle, F.H., Jagucki, M.L., and McMahon, P.B., 1994,

Effect of atrazine on potential denitrification in aquifer sediments: Soil Biology and Biochemistry, v. 26, no. 4, p. 523-524, doi:10.1016/0038-0717(94)90186-4.

Bratkovich, A., Dinnel, S.P., and Goolsby, D.A., 1995,

Variability and prediction of freshwater and nitrate fluxes for the Louisiana-Texas shelf--Mississippi and Atchafalaya source functions: Estuaries, v. 17, no. 4, p. 766-778.

Bratton, J.F., Böhlke, J.K., Manheim, F.T., and Krantz, D.E., 2004,

Ground water beneath coastal bays of the Delmarva Peninsula--Ages and nutrients: Ground Water, v. 42, no. 7, p. 1021-1034, doi:10.1111/j.1745-6584.2004.tb02641.x.

Brown, J.B., and Battaglin, W.A., 2007,

Striving for collaborative science and communication through the Consortium for Research and Education on Emerging Contaminants (CREEC): Water Resources Impact, v. 9, no. 3, p. 22-24.

Burkart, M., Kolpin, D.W., Jaquis, R., and Cole, K., 2001,

Soil characteristics and agrichemicals in groundwater of the midwestern United States: Water Science and Technology, v. 43, no. 5, p. 251-260.

Burkart, M.R., 1991,

Hydrogeologic research on agrichemicals in the Midcontinental United States, in Water Quality Workshop for Eastern Europe, Poznan, Poland, Proceedings, September 23-26, 1991: p. 22.

Burkart, M.R., 1990,

Interagency research and technical integration, in Information exchange on models and data needs relating to the impact of agricultural practices on water quality--Workshop Proceedings, Reston, Virginia, February 5-8, 1990: U.S. Geological Survey, Office Water Data Coordination, p. 11-12.

Burkart, M.R., and Kolpin, D.W., 1993,

Regional assessment of factors related to herbicides and nitrate in near-surface aquifers of the midcontinent, in Agricultural research to protect water quality--Proceedings of the Conference, Minneapolis, Minn., February 21-24, 1993: Ankeny, Iowa, Soil and Water Conservation Society, p. 390-392.

Burkart, M.R., Kolpin, D.W., and James, D.E., 1999,

Assessing groundwater vulnerability to agrichemical contamination in the midwest U.S.: Water Science and Technology, v. 39, no. 3, p. 103-112.

Burkart, M.R., Kolpin, D.W., Jaquis, R.J., and Cole, K.J., 1999,

Agrichemicals in ground water of the Midwestern USA--Relations to soil characteristics: Journal of Environmental Quality, v. 28, no. 6, p. 1908-1915.

Burkart, M.R., and Ragone, S.A., 1989,

Planned studies of herbicides in ground and surface water in the Midcontinental United States, in Papers from International Symposium on Integrated Approaches to Water Pollution Problems, Lisbon, Portugal, June 19-23, 1989: International Water Resources Association, v. 3, p. 475-477.

Burkart, M.R., Ragone, S.E., Thurman, E.M., and Perry, C.A., 1989,

Planned studies of herbicides in ground and surface water in the Midcontinental United States, in Mallard, G.E., and Ragone, S.E., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Phoenix, Arizona, September 26-30, 1988: U.S. Geological Survey Water-Resources Investigations Report 88-4220, p. 445-452.

Burkholder, J., Libra, B., Weyer, P., Heathcote, S., Kolpin, D.W., Thorne, P.S., and Wichman, M., 2007,

Impacts of waste from concentrated animal feeding operations (CAFOs) on water quality: Environmental Health Perspectives, v. 115, no. 2, p. 308-312, doi:10.1289/ehp.8839.

Burkholder, J., Libra, B., Weyer, P., Heathcote, S., Kolpin, D.W., Thorne, P.S., and Wichman, M., 2006,

Impacts of waste from concentrated animal feeding operations on water quality: Environmental Health Perspectives, v. 115, no. 2, p. 308–312, doi:10.1289/ehp.8839.

Buszka, P.M., 1987,

Relation of water chemistry of the Edwards aquifer to hydrogeology and land use, San Antonio Region, Texas: U.S. Geological Survey Water-Resources Investigations Report 87-4116, 100 p.

Butler, D.L., Kruger, R., Miller, T., and McCall, S., 1992,

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Gunnison River area, Colorado, 1988-89: U.S. Geological Survey Water-Resources Investigations Report 91-4103, 99 p.

CENR, 2000,

Integrated assessment of hypoxia in the northern Gulf of Mexico: National Science and Technology Council Committee on Environment and Natural Resources, Washington, D.C., 58 p.

Cain, D.J., and Edelmann, P., 1987,

A reconnaissance water-quality appraisal of the Fountain Creek Alluvial Aquifer between Colorado Springs and Pueblo, Colorado, including trace elements and organic constituents: U.S. Geological Survey Water-Resources Investigations Report 86-4085, 45 p.

Cain, D.J., Helsel, D.R., and Ragone, S.E., 1989,

Preliminary evaluations of regional ground-water quality in relation to land use: Ground Water, v. 27, no. 2, p. 230-244.

Cain, D.J., Helsel, D.R., and Ragone, S.E., 1987,

Reconnaissance appraisals of anthropogenic effects on regional ground-water quality, in Franks, B.J., ed., U.S. Geological Survey Program on Toxic Waste--Ground-Water Contamination--Proceedings of the third technical meeting, Pensacola, Florida, March 23-27, 1987: U.S. Geological Survey Open-File Report 87-109, p. E-25-E-31.

Cameron, C.C., 1993,

Recognition of natural chemical filters in the Minnesota MSEA, in Agricultural Research to Protect Water Quality--Proceedings of the Conference, Minneapolis, Minn., February 21-24, 1993: Ankeny, Iowa, Soil and Water Conservation Society, p. 471-474.

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Agricultural chemicals in surface-water resources of the Midcontinental United States, in American Water Resources Association, NAWQA (National Water Quality Assessment Program) session, Proceedings, New Orleans, September, 1991: p. 373-374.

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Nitrogen flux and sources in the Mississippi River Basin: The Science of the Total Environment, v. 248, no. 2-3, p. 75-86, doi:10.1016/S0048-9697(99)00532-X.

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Persistence of herbicides in selected reservoirs in the midwestern United States--Some preliminary results: Iowa Groundwater Quarterly, v. 7, no. 2, p. 11-16 (reprinted from U.S. Geological Survey Open-File Report 93-418).

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Persistence of herbicides in selected reservoirs in the Midwestern United States--Some preliminary results, in Goolsby, D.A., Boyer, L.L., and Mallard, G.E., eds., Selected papers on agricultural chemicals in water resources of the Midcontinental United States: U.S. Geological Survey Open-File Report 93-418, p. 51-63.

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Flux and sources of nutrients in the Mississippi-Atchafalaya River Basin--Topic 3, Report for the integrated assessment on hypoxia in the Gulf of Mexico: National Oceanic and Atmospheric Administration NOAA Coastal Ocean Program Decision Analysis Series No. 17, 129 p.

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Occurrence and transport of herbicides and nitrate in the Mississippi River during the 1993 flood--Proceedings of American Water Resources Association meeting, in, Nashville, Tenn., April 17-20, 1994: p. 473-477.

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Occurrence and transport of agricultural chemicals in the Mississippi River basin, July through August 1993--Floods in the Upper Mississippi River Basin, 1993: U.S. Geological Survey Circular 1120-C, 22 p.

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Plan of study to determine the effect of changes in herbicide use on herbicide concentrations in midwestern streams, 1989-94: U.S. Geological Survey Open-File Report 94-347, 14 p.

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Distribution of selected herbicides and nitrate in the Mississippi River and its major tributaries, April through June 1991: U.S. Geological Survey Water-Resources Investigations Report 91-4163, 35 p.

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Sources and transport of nitrogen in the Mississippi River Basin, in Proceedings "From the Corn Belt to the Gulf...Agriculture and Hypoxia in the Mississippi River Watershed," American Farm Bureau Federation Workshop, St Louis, Missouri, July 14-15, 1997: St Louis, Missouri, American Farm Bureau Federation, p. 59-64 (document has no page numbers).

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Pesticides in the Mississippi River, in Meade, R.H., ed., Contaminants in the Mississippi River: U.S. Geological Survey Circular 1133, p. 86-101.

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Data on selected herbicides and two triazine metabolites in precipitation in the midwestern and northeastern United States, 1990-91: U.S. Geological Survey Open-File Report 95-469, 341 p.

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Geochemistry of soils and shallow ground water, with emphasis on arsenic and selenium, in part of the Garrison Diversion Unit, North Dakota, 1985-87: U.S. Geological Survey Water-Resources Investigations Report 89-4104, 132 p.

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Herbicides in rivers and streams of the Upper Midwestern United States, in The Proceedings of the 46th Annual Meeting of the Upper Mississippi River Conservation Committee, Bettendorf, Iowa, March 13-15, 1990: p. 99-106.

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Pesticides in streams of the Upper Midwestern United States, in Proceedings of the 7th Annual Water and the Future of Kansas Conference, Manhattan, Kansas, March 7-8, 1990: p. 27-28.

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Immunoassay as a screening tool for triazine herbicides in streams--comparison with gas chromatographic-mass spectrometric methods, in Vanderlaan, M., Stanker, L.H., Watkins, B.E., and Roberts, D.E., eds., Immunoassays for Trace Chemical Analysis--Monitoring toxic chemicals in humans, food, and the environment: Washington, D.C., American Chemical Society ACS Symposium Series 451, p. 86-99.

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Geographic and temporal distribution of herbicides in surface waters of the Upper Midwestern United States, 1989-90, in Mallard, G.E., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Monterey, California, March 11-15, 1991: U.S. Geological Survey Water-Resources Investigations Report 91-4034, p. 183-188.

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Herbicides in streams--Midwestern United States, in ASE Irrigation and Drainange Engineering Conference, Proceedings, Honolulu, Hawaii, July 22-26, 1991: p. 17-23.

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Occurrence of herbicides and metabolites in surface water, ground water and rainwater, in the midwestern United States--Proceedings of 1995 AWWA Conference, in, Anaheim, CA, June 18-22, 1995: p. 583-591.

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Herbicides and metabolites in surface water, rainwater, and ground water in the midwestern United States--Proceedings of 209th ACS National Meeting, in, Anaheim, California, April 2-7, 1995: p. 278-281.

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Temporal and geographic distribution of herbicides in precipitation in the midwest and northeast United States, 1990-91--Proceedings of the Fourth National Pesticide Conference, in, Richmond, Va., November 1-3, 1993: p. 697-710.

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Occurrence, deposition, and long range transport of herbicides in precipitation in the Midwestern and Northeastern United States, in Morganwalp, D.W., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water-Resources Investigations Report 94-4015, v. 1, p. 411-421.

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Occurrence, deposition, and long range transport of herbicides in precipitation in the Midwestern and Northeastern United States, in Goolsby, D.A., Boyer, L.L., and Mallard, G.E., eds., Selected papers on agricultural chemicals in water resources of the Midcontinental United States: U.S. Geological Survey Open-File Report 93-418, p. 75-89.

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Herbicides and their metabolites in rainfall--Origin, transport, and deposition patterns across the midwestern and northeastern United States, 1990-1991: Environmental Science and Technology, v. 31, no. 5, p. 1325-1333, doi:10.1021/es960847o.

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Statistical comparison of ground-water quality in four land-use areas of stratified-drift aquifers in Connecticut, in Mallard, G.E., and Ragone, S.E., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Phoenix, Arizona, September 26-30, 1988: U.S. Geological Survey Water-Resources Investigations Report 88-4220, p. 473-481.

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Evaluation of groundwater quality in relation to land use for stratified-drift aquifers in Connecticut, in Ragone, S.E., ed., Regional characterization of water quality--Proceedings of the Baltimore Symposium, May, 1989: International Association of Hydrological Sciences, Publ. 182, p. 19-29.

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Preliminary appraisal of the effects of land use on water quality in stratified-drift aquifers in Connecticut: U.S. Geological Survey Water-Resources Investigations Report 87-4005, 41 p.

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Metolachlor and alachlor breakdown product formation patterns in aquatic field mesocosms: Environmental Science and Technology, v. 33, no. 24, p. 4471-4476, doi:10.1021/es990686z.

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Investigation of water quality, bottom sediment, and biota associated with irrigation drainage from the Angostura Reclamation Unit area, southwestern South Dakota, 1988, in Mallard, G.E., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Monterey, California, March 11-15, 1991: U.S. Geological Survey Water-Resources Investigations Report 91-4034, p. 358-364.

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Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Angostura Reclamation Unit, southwestern South Dakota 1988-89: U.S. Geological Survey Water-Resources Investigations Report 90-4152, 75 p.

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Chemical results for bottom material for Department of the Interior Irrigation and Drainage Task Group studies 1988-1989, Denver, Colorado: U.S. Geological Survey Open-File Report 90-50, 47 p.

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Use of geographic information systems and scanning technology to create high-resolution historical land-use data sets: U.S. Geological Survey Water-Resources Investigations Report 96-4100, 41 p.

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Management systems evaluation areas--An overview, in Agricultural Research to Protect Water Quality--Proceedings of the Conference, Minneapolis, Minn., February 21-24, 1993: Ankeny, Iowa, Soil and Water Conservation Society, p. 1-15.

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Combined agriculture (MSEA) and ecology (MASTER) project on water quality in Iowa, in Agricultural Research To Protect Water Quality--Proceedings of the Conference, Minneapolis, Minn., February 21-24, 1993: Ankeny, Iowa, Soil and Water Conservation Society, p. 48-59.

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A visual/interactive method for examining the National Stream Quality Accounting Network (NASQAN) data--Proceedings of Watershed'96, in, Baltimore, Md., June 8-12, 1996: p. 317-319.

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Effects of land-use buffer size on Spearman's partial correlations of land use and shallow ground-water quality: U.S. Geological Survey Water-Resources Investigations Report 89-4163, 28 p.

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Assessment of nonpoint-source contamination of the High Plains aquifer in south-central Kansas, 1987, Chapter C of Analysis of nonpoint-source ground-water contamination in relation to land use: U.S. Geological Survey Water-Supply Paper 2381-C, 51 p.

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Overview of nonpoint-source contamination of the High Plains aquifer in south-central Kansas, in Mallard, G.E., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Monterey, California, March 11-15, 1991: U.S. Geological Survey Water-Resources Investigations Report 91-4034, p. 301-306.

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Trace organic compounds in ground water in south-central Kansas as inferred from gas/chromatography with flame-ionization detection, in Preprints of Papers Presented at the 196th ACS National Meeting, Division of Environmental Chemistry, Los Angeles, California, September 25-30, 1988: Washington, D.C., American Chemical Society, v. 28, no. 2, p. 9-12.

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Evaluation of regional ground-water quality in relation to land use; U.S. Geological Survey Toxic Waste--Ground-Water Contamination Program: U.S. Geological Survey Water-Resources Investigations Report 84-4217, 33 p.

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Study design to investigate and simulate agricultural fate in a ground-water recharge system (Plains, Georgia), in Proceedings of the American Society for Agronomy, San Antonio, Texas.

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Movement and fate of agricultural chemicals in the surface and subsurface environ-ments near Plains, southwestern Georgia--Integrated work plan: U.S. Geological Survey Open-File Report 91-73, 26 p.

Hicks, D.W., McConnell, J.B., and Asmussen, L.E., 1991,

Preliminary geologic and hydrologic evalution of a small watershed near Plains, Georgia: U.S. Geological Survey Water-Resources Investigations Report 90-4146, 30 p.

Hicks, D.W., McConnell, J.B., and Asmussen, L.E., 1988,

The effect of infiltration and transport mechanisms on nitrate and chloride concentrations beneath a small watershed near Plains, Georgia, in Mallard, G.E., and Ragone, S.E., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Phoenix, Arizona, September 26-30, 1988: U.S. Geological Survey Water-Resources Investigations Report 88-4220, p. 638.

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Effect of the unsaturated zone on the migration and retardation of a conservative tracer at the Plains, Georgia, research site, in Mallard, G.E., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Monterey, California, March 11-15, 1991: U.S. Geological Survey Water-Resources Investigations Report 91-4034, p. 597-600.

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Two-dimensional distribution of a bromide tracer in the unsaturated zone at the Plains, Georgia, research site, in Morganwalp, D.W., and Aronson, D.A., eds., U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water-Resources Investigations Report 94-4015, v. 2, p. 971-982.

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Preliminary report of potentially toxic trace elements and pesticides in water, sediment, and biota in and near the Stillwater Wildlife Management Area, Churchill County, Nevada, 1986-87, Department of the Interior Irrigation Drainage Program, in Howard, A.Q., ed., Selenium and agricultural drainage--Implications for San Francisco Bay and the California environment--Proceedings of the Fourth Selenium Symposium, Berkeley, Calif., March 21, 1987: Sausalito, Calif., The Bay Institute of San Fransisco, p. 163-167.

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