Date of this Version
Scribner, E.a., E. M. Thurman, D.A. Goolsby, M.T. Meyer, M.S. Mills, and M.L. Pomes, 1993. Reconnaissance Data for Selected Herbicides, Two Atrazine Metabolites, and Nitrate in Surface Water of the Midwestern United States, 1989-90. U.S. GEOLOGICAL SURVEY Open-File Report 93-457. Lawrence, Kansas. 83 pp.
Water-quality data were collected from 147 rivers and streams during 1989-90 to determine the temporal and geographic distribution of selected preemergent herbicides, two atrazine metabolites, and nitrate in 10 Midwestern States. This report includes a description of the sampling design, data-collection techniques, laboratory and analytical methods, and a compilation of constituent concentrations and quality-assurance data. All water samples were collected by depth-integrating techniques at three to five locations across the wetted perimeter of each stream. Sites were sampled three times in 1989~before application of herbicides, during the first major runoff after application of herbicides, and in the fall during a low-flow period when most of the streamflow was derived from ground water. About 50 sites were selected by a stratified random procedure and resampled for both pre- and post-application herbicide concentrations in 1990 to verify the 1989 results. Laboratory analyses consisted of both enzyme-linked immunosorbent assay (ELISA) and confirmation by gas chromatography/ mass spectrometry (GC/MS). The data have been useful in studying herbicide transport, in comparison of the spatial distribution of the post-application concentrations of 11 herbicides and 2 atrazine metabolites (deethylatrazine and deisopropylatrazine) in streams and rivers at a regional scale, in examination of the annual persistence of herbicides and two atrazine metabolites in surface water, and in assessment of atrazine metabolites as indicators of surface- and ground-water interaction.