Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
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Field determination of the three-dimensional hydraulic conductivity tensor of anisotropic media: 2. Methodology and application to fractured rocks Field determination of the three-dimensional hydraulic conductivity tensor of anisotropic media: 2. Methodology and application to fractured rocks
The analytical solutions developed in the first paper can be used to interpret the results of cross-hole tests conducted in anisotropic porous or fractured media. In the particular case where the injection and monitoring intervals are short relative to the distance between them, the test results can be analyzed graphically. From the transient variation of hydraulic head in a given...
Authors
Paul A. Hsieh, Shlomo P. Neuman, Gary K. Stiles, Eugene S. Simpson
Separation of solute and particulate vectors of heavy metal uptake in controlled suspension-feeding experiments with Macoma balthica Separation of solute and particulate vectors of heavy metal uptake in controlled suspension-feeding experiments with Macoma balthica
Radioisotope labelling experiments with the estuarine clam, Macoma balthica, are described, in which a filter chamber device was used to separate solute metal uptake from uptake, of metals associated with suspended bacteria. Solute uptake contributed a majority of the 14-day total body burdens of 65Zn and 109Cd, whereas 57Co uptake largely resulted from ingestion of isotope-laden...
Authors
Ronald W. Harvey, Samuel N. Luoma
Geochemical investigations of polychlorinated dibenzo-p-dioxins in the subsurface environment at an abandoned wood-treatment facility Geochemical investigations of polychlorinated dibenzo-p-dioxins in the subsurface environment at an abandoned wood-treatment facility
The discharge of effluents containing creosote and pentachlorophenol into two unlined surface impoundments at a wood-treatment facility in Pensacola, Florida, resulted in contamination of the underlying sand and gravel aquifer. These wastes contained significant amounts of chlorinated dioxins, such as isomers of hexa- and heptachlorodibenzo-p-dioxins and octachlorodibenzo-p-dioxin...
Authors
W. E. Pereira, C.E. Rostad, M.E. Sisak
Reduction of hexavalent chromium in water samples acidified for preservation Reduction of hexavalent chromium in water samples acidified for preservation
Reduction of hexavalent chromium, Cr(VI), in water samples, preserved by standard techniques, was investigated. The standard preservation technique for water samples that are to be analyzed for Cr(VI) consists of filtration through a 0.45‐µm membrane, acidification to a pH 2, and storage in plastic bottles. Batch experiments were conducted to evaluate the effect of H+ concentration, NO2
Authors
Kenneth G. Stollenwerk, D.B. Grove
Modeling the rate-controlled sorption of hexavalent chromium Modeling the rate-controlled sorption of hexavalent chromium
Sorption of chromium VI on the iron-oxide- and hydroxide-coated surface of alluvial material was numerically simulated with rate-controlled reactions. Reaction kinetics and diffusional processes, in the form of film, pore, and particle diffusion, were simulated and compared with experimental results. The use of empirically calculated rate coefficients for diffusion through the reacting...
Authors
D.B. Grove, Kenneth G. Stollenwerk
Adsorption and desorption of hexavalent chromium in an alluvial aquifer near Telluride, Colorado Adsorption and desorption of hexavalent chromium in an alluvial aquifer near Telluride, Colorado
A laboratory investigation of reactions between hexavalent chromium [Cr(VI)] and alluvium was conducted to evaluate reactions of Cr(VI) contaminating an alluvial aquifer near Telluride, CO and to determine the mechanisms responsible for these reactions. Uncontaminated alluvium and groundwater (spiked with CrO42−) from the study site were used in batch and column experiments. Results of...
Authors
Kenneth G. Stollenwerk, D.B. Grove
Migration of wood-preserving chemicals in contaminated groundwater in a sand aquifer at Pensacola, Florida Migration of wood-preserving chemicals in contaminated groundwater in a sand aquifer at Pensacola, Florida
Operation of a wood-preserving facility for nearly 80 years at Pensacola, FL, contaminated the near-surface groundwater with creosote and pentachlorophenol. The major source of aquifer contamination was unlined surface impoundments that were in direct hydraulic contact with the groundwater. Episodes of overtopping the impoundments and overland flow of treatment liquor and waste were also
Authors
D.F. Goerlitz, D.E. Troutman, E.M. Godsy, B.J. Franks
Unit hydrograph approximations assuming linear flow through topologically random channel networks Unit hydrograph approximations assuming linear flow through topologically random channel networks
The instantaneous unit Hydrograph (IUH) of a drainage basin is derived in terms of fundamental basin characteristics (Z, α, β), where α parameterizes the link (channel segment) length distribution, and β is a vector of hydraulic parameters, Z is one of three basin topological properties, N, (N, D), or (N, M), where N is magnitude (number of first-order streams), D is diameter (mainstream...
Authors
Brent M. Troutman, Michael R. Karlinger
Soil sorption of organic vapors and effects of humidity on sorptive mechanism and capacity Soil sorption of organic vapors and effects of humidity on sorptive mechanism and capacity
No abstract available.
Authors
C. T. Chiou, T.D. Shoup
Partition coefficients of organic compounds in lipid-water systems and correlations with fish bioconcentration factors Partition coefficients of organic compounds in lipid-water systems and correlations with fish bioconcentration factors
Triolein-water partition coefficients (KtW) have been determined for 38 slightly water-soluble organic compounds, and their magnitudes have been compared with the corresponding octanol-water partition coefficients (KOW). In the absence of major solvent-solute interaction effects in the organic solvent phase, the conventional treatment (based on Raoult's law) predicts sharply lower...
Authors
C. T. Chiou
Culturing Selenastrum capricornutum (Chlorophyta) in a synthetic algal nutrient medium with defined mineral particulates Culturing Selenastrum capricornutum (Chlorophyta) in a synthetic algal nutrient medium with defined mineral particulates
Algal nutrient studies in chemically-defined media typically employ a synthetic chelator to prevent iron hydroxide precipitation. Micronutrient-particulate interactions may, however, significantly affect chemical speciation and hence biovailability of these nutrients in natural waters. A technique is described by which Selenastrum capricornutum Printz (Chlorophyta) may be cultured in a...
Authors
James S. Kuwabara, J.A. Davis, Cecily C.Y. Chang
Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution
Sedimentologic and biostratigraphic evidence is used to develop a geochemical model for Great Salt Lake, Utah, extending back some 30,000 yrs. B.P. Hydrologie conditions as defined by the water budget equation are characterized by a lake initially at a low, saline stage, rising by about 17,000 yrs. B.P. to fresh water basin-full conditions (Bonneville level) and then, after about 15,000...
Authors
R. J. Spencer, H.P. Eugster, B.F. Jones