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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: 4098

A model for trace metal sorption processes at the calcite surface: Adsorption of Cd2+ and subsequent solid solution formation A model for trace metal sorption processes at the calcite surface: Adsorption of Cd2+ and subsequent solid solution formation

The rate of Cd2+ sorption by calcite was determined as a function of pH and Mg2+ in aqueous solutions saturated with respect to calcite but undersaturated with respect to CdCO3. The sorption is characterized by two reaction steps, with the first reaching completion within 24 hours. The second step proceeded at a slow and nearly constant rate for at least 7 days. The rate of calcite
Authors
J.A. Davis, C. C. Fuller, A.D. Cook

Isolation of nonvolatile, organic solutes from natural waters by zeotrophic distillation of water from N,N-dimethylformamide Isolation of nonvolatile, organic solutes from natural waters by zeotrophic distillation of water from N,N-dimethylformamide

Nonvolatile, organic solutes that comprise the dissolved organic carbon (DOC) in saline waters were isolated by removal of the water by distillation from a N,N-dimethylformamideformic acid-acetonitrile mixture. Salts isolated with the DOC were removed by crystallization of sodium chloride and sodium sulfate from the solvent mixture, removal of silicic acid by acidification and...
Authors
J.A. Leenheer, P.A. Brown, E.A. Stiles

Creosote compounds in snails obtained from Pensacola Bay, Florida, near an onshore hazardous-waste site Creosote compounds in snails obtained from Pensacola Bay, Florida, near an onshore hazardous-waste site

Snails, Thais haemostoma, were collected from two areas offshore in Pensacola Bay, Florida, near an onshore hazardous-waste site. Tissue from the snails was extracted to isolate the lipophilic compounds and analyzed by gas chromatography/mass spectrometry. Along with naturally occurring compounds, the snail tissue contained large concentrations of polycyclic aromatic compounds, such as
Authors
Colleen E. Rostad, W. E. Pereira

A compositional multiphase model for groundwater contamination by petroleum products: 2. Numerical solution A compositional multiphase model for groundwater contamination by petroleum products: 2. Numerical solution

In this paper we develop a numerical solution to equations developed in part 1 (M. Y. Corapcioglu and A. L. Baehr, this issue) to predict the fate of an immiscible organic contaminant such as gasoline in the unsaturated zone subsequent to plume establishment. This solution, obtained by using a finite difference scheme and a method of forward projection to evaluate nonlinear coefficients...
Authors
Arthur L. Baehr, M. Yavuz Corapcioglu

Solute transport with equilibrium aqueous complexation and either sorption or ion exchange: Simulation methodology and applications Solute transport with equilibrium aqueous complexation and either sorption or ion exchange: Simulation methodology and applications

Methodologies that account for specific types of chemical reactions in the simulation of solute transport can be developed so they are compatible with solution algorithms employed in existing transport codes. This enables the simulation of reactive transport in complex multidimensional flow regimes, and provides a means for existing codes to account for some of the fundamental chemical...
Authors
F.M. Lewis, Clifford I. Voss, J. Rubin

Characterization of fracture permeability with high-resolution vertical flow measurements during borehole pumping. Characterization of fracture permeability with high-resolution vertical flow measurements during borehole pumping.

The distribution of fracture permeability in granitic rocks was investigated by measuring the distribution of vertical flow in boreholes during periods of steady pumping. Pumping tests were conducted at two sites chosen to provide examples of moderately fractured rocks near Mirror Lake, New Hampshire and intensely fractured rocks near Oracle, Arizona. A sensitive heat-pulse flowmeter was...
Authors
Frederick L. Paillet, A.E. Hess, C.H. Cheng, E. Hardin

Determination of alkylbenzenesulfonate surfactants in groundwater using macroreticular resins and carbon-13 nuclear magnetic resonance spectrometry Determination of alkylbenzenesulfonate surfactants in groundwater using macroreticular resins and carbon-13 nuclear magnetic resonance spectrometry

Alkylbenzenesulfonate surfactants were determined in groundwater at concentrations as low as 0.3 mg/L. The method uses XAD-8 resin for concentration, followed by elution with methanol, separation of anionic and nonionic surfactants by anion exchange, quantitation by titration, and identification by 13C nuclear magnetic resonance spectrometry. Laboratory standards and field samples...
Authors
E. Michael Thurman, T. Willoughby, Larry B. Barber, Kevin A. Thorn

Formation of methane and carbon dioxide from dimethylselenide in anoxic sediments and by a methanogenic bacterium Formation of methane and carbon dioxide from dimethylselenide in anoxic sediments and by a methanogenic bacterium

Anaerobic San Francisco Bay salt marsh sediments rapidly metabolized [14C]dimethylselenide (DMSe) to 14CH4 and 14CO2. Addition of selective inhibitors (2-bromoethanesulfonic acid or molybdate) to these sediments indicated that both methanogenic and sulfate-respiring bacteria could degrade DMSe to gaseous products. However, sediments taken from the selenium-contaminated Kesterson Wildlife...
Authors
Ronald S. Oremland, Jon P. Zehr

A new formula for the analytical solution of the radial dispersion problem A new formula for the analytical solution of the radial dispersion problem

A new formula is presented for the analytical solution of the radial dispersion problem, which analyzes the dispersive transport of a tracer in radial flow from a recharge well. This formula is simpler than a solution presented by previous investigators, but the two solutions are shown to be equivalent. Because the analytical solution consists of an integral of an oscillatory function...
Authors
Paul A. Hsieh
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