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Publications

Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).

Filter Total Items: 4094

Selected meteorological data for an arid site near Beatty, Nye County, Nevada, calendar year 1986

Selected meteorological data were collected at a study site adjacent to a low-level radioactive-waste burial facility near Beatty, Nevada, for calendar year 1986. Data were collected in support of an ongoing study to estimate the potential for downward movement of radionuclides into the unsaturated sediments beneath waste-burial trenches at the facility. The data include air temperature, relative
Authors
James L. Wood, Jeffrey M. Fischer

Selected hydrologic data for the upper Arkansas River basin, Colorado, 1986-89

No abstract available.
Authors
Gregory A. Wetherbee, Briant A. Kimball, Wendy S. Maura

Brine evolution and mineral deposition in hydrologically open evaporite basins

A lumped-parameter, solute mass-balance model is developed to define the role of water outflow from a well-mixed basin. A mass-balance model is analyzed with a geochemical model designed for waters with high ionic strengths. Two typical waters, seawater and a Na-HCO3 ground water, are analyzed to illustrate the control that the leakage ratio (or hydrologic openness of the basin) has on brine evolu
Authors
W. E. Sanford, W.W. Wood

Use of colloid filtration theory in modeling movement of bacteria through a contaminated sandy aquifer

\A filtration model commonly used to describe removal of colloids during packed-bed filtration in water treatment applications was modified for describing downgradient transport of bacteria in sandy, aquifer sediments. The modified model was applied to the results of a small-scale (7 m), natural-gradient tracer test and to observations of an indigenous bacterial population moving downgradient with
Authors
R.W. Harvey, S. P. Garabedian

Importance of closely spaced vertical sampling in delineating chemical and microbiological gradients in groundwater studies

Vertical gradients of selected chemical constituents, bacterial populations, bacterial activity and electron acceptors were investigated for an unconfined aquifer contaminated with nitrate and organic compounds on Cape Cod, Massachusetts, U.S.A. Fifteen-port multilevel sampling devices (MLS's) were installed within the contaminant plume at the source of the contamination, and at 250 and 2100 m dow
Authors
R. L. Smith, R.W. Harvey, D.R. LeBlanc

Denitrification in nitrate-contaminated groundwater: Occurrence in steep vertical geochemical gradients

A relatively narrow vertical zone (5–6 m thick) of NO3− containing groundwater was identified using multilevel sampling devices in a sand and gravel aquifer on Cape Cod, MA, USA. The aquifer has been chronically contaminated by surface disposal of treated sewage 0.3 km upgradient from the study area. The NO3− zone was anoxic and contained high concentrations of N2O (16.5 μM), suggesting that it wa
Authors
R. L. Smith, B.L. Howes, J.H. Duff

Herbicides in surface waters of the midwestern United States: The effect of spring flush

Approximately three-fourths of all preemergent herbicides used in the United States are applied to row crops over a 12-state area, called the "corn belt" (I). The application of these compounds may cause widespread degradation of water quality (2). Because herbicides are water soluble, there is the potential for leaching into groundwater and surface water (3, 4), as well as aerial transport and Oc
Authors
E.M. Thurman, D. A. Goolsby, M. T. Meyer, D.W. Kolpin

Formation and transport of deethylatrazine in the soil and vadose zone

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) and two degradation products were monitored at seven depths in the soil and vadose zone throughout the growing season in two experimental plots in which corn (Zea mays L.) was grown. The soils in these plots were a Kimo silty clay loam (clayey over loamy, montmorillonitic, mesic, Fluvaquentic Hapludoll) and a Eudora silt loam (course, si
Authors
C.D. Adams, E.M. Thurman

Large-scale distribution of metal contamination in the fine-grained sediments of the Clark Fork River, Montana, U.S.A.

Historic discharges from the mining and smelting complex at the head-waters of the Clark Fork River have resulted in elevated Ag, Cd, Cu, Pb and Zn concentrations in the <60 μm fraction of both bed and flood-plain sediments of the river. Processes affecting the trends in longitudinal distributions of these metals were investigated by repeated sampling over a 380 km river reach between August 1986
Authors
E.V. Axtmann, S. N. Luoma

Balloon and core sampling for determining bulk density of alluvial desert soil

Samples were collected from major strata in the upper 5 m of an alluvial soil profile in the Amargosa Desert of southern Nevada to compare rubber-balloon and drive-core bulk-density measurement methods. For strate where the fine soil was <82% sand and <15% clay, differences between total and fine-soil bulk-density values determined by the two methods were typically <10 and 15%, respectively, even
Authors
Brian J. Andraski