Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
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Aqueous pyrite oxidation by dissolved oxygen and by ferric iron
Rates of aqueous, abiotic pyrite oxidation were measured in oxygen-saturated and anaerobic Fe(III)-saturated solutions with initial pH from 2 to 9. These studies included analyses of sulfite, thiosulfate, polythionates and sulfate and procedures for cleaning oxidation products from pyrite surfaces were evaluated. Pyrite oxidation in oxygen-saturated solutions produced (1) rates that were only slig
Authors
Carl O. Moses, D. Kirk Nordstrom, Janet S. Herman, Aaron L. Mills
Increased solubility of quartz in water due to complexing by organic compounds
Quartz is the most stable natural solid phase of silica. It weathers extremely slowly at the Earth's surface1, and often resists weathering even after all other silicate minerals have been degraded. However, there is ample evidence from both ancient and modern environments indicating enhanced dissolution and mobility of silica under conditions that cannot easily be explained by the inorganic contr
Authors
P. Bennett, D. I. Siegel
Monodisperse ferrous phosphate colloids in an anoxic groundwater plume
Groundwater samples collected near a secondary-sewage infiltration site on Cape Cod, Massachusetts were examined for colloidal materials (10–1000 nm). In two wells the water contained a population of monodisperse 100-nm particles, detected using laser-light scattering and autocorrelation data processing. SEM and SEM-EDAX analysis of these colloidal materials collected on ultrafilters confirmed the
Authors
Philip M. Gschwend, Matthew D. Reynolds
Some effects of acid mine drainage on Clear Creek, Colorado
No abstract available.
Authors
W. H. Ficklin, K. S. Smith, Katherine Walton-Day
Inhibition of aqueous copper and lead adsorption onto goethite by dissolved carbonate species
No abstract available.
Authors
Kathleen S. Smith, D. Langmuir
Fitting straight lines in the earth sciences
No abstract available.
Authors
B.M. Troutman, G. P. Williams
Bioconcentration of creosote compounds in snails obtained from Pensacola Bay, Florida, near an onshore hazardous-waste site
No abstract available.
Authors
C. E. Rostad, W. E. Pereira
Big Soda Lake (Nevada). 1. Pelagic bacterial heterotrophy and biomass
Bacterial activities and abundance were measured seasonally in the water column of meromictic Big Soda Lake which is divided into three chemically distinct zones: aerobic mixolimnion, anaerobic mixolimnion, and anaerobic monimolimnion. Bacterial abundance ranged between 5 and 52 x 106 cells ml−1, with highest biomass at the interfaces between these zones: 2–4 mg C liter−1 in the photosynthetic bac
Authors
Jon P. Zehr, Ronald W. Harvey, Ronald S. Oremland, James E. Cloern, Leah H. George, Judith L. Lane
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 containing strai
Authors
E. Michael Thurman, T. Willoughby, Larry B. Barber, Kevin A. Thorn
Growth determinations for unattached bacteria in a contaminated aquifer
Growth rates of unattached bacteria in groundwater contaminated with treated sewage and collected at various distances from the source of contamination were estimated by using frequency of dividing cells and tritiated-thymidine uptake and compared with growth rates obtained with unsupplemented, closed-bottle incubations. Estimates of bacterial generation times [(In 2)/μ] along a 3-km-long transect
Authors
R.W. Harvey, L.H. George
Reduction of selenate to selenide by sulfate-respiring bacteria: Experiments with cell suspensions and estuarine sediments
Washed cell suspensions of Desulfovibrio desulfuricans subsp. aestuarii were capable of reducing nanomolar levels of selenate to selenide as well as sulfate to sulfide. Reduction of these species was inhibited by 1 mM selenate or tungstate. The addition of 1 mM sulfate decreased the reduction of selenate and enhanced the reduction of sulfate. Increasing concentrations of sulfate inhibited rates of
Authors
J.P. Zehr, Ronald S. Oremland
Direct comparison of kinetic and local equilibrium formulations for solute transport affected by surface reactions
Modeling transport of reacting solutes in porous media often requires a choice between models based on the local equilibrium assumption (LEA) and models involving reaction kinetics. Direct comparison of the mathematical formulations for these two types of transport models can aid in this choice. For cases of transport affected by surface reaction, such a comparison is made possible by a new deriva
Authors
Jean M. Bahr, Jacob Rubin