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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: 3787

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, probably derive
Authors
W. E. Pereira, C.E. Rostad, M.E. Sisak

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 surface was
Authors
D.B. Grove, Kenneth G. Stollenwerk

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 partition coeffi
Authors
C. T. Chiou

Dissolution of alkaline earth sulfates in the presence of montmorillonite

In a study of the effect of montmorillonite on the dissolution of BaSO4 (barite), SrSO4 (celestite), and 226Ra from U mill tailings, it was found that: (1) More of these substances dissolve in an aqueous system that contains montmorillonite than dissolve in a similar system without clay, due to the ion exchange properties of the clay; (2) Na-montmorillonite is more effective in aiding dissolution
Authors
D. D. Eberl, Edward R. Landa

Errors and parameter estimation in precipitation-runoff modeling: 2. Case study

A case study is presented which illustrates some of the error analysis, sensitivity analysis, and parameter estimation procedures reviewed in the first part of this paper. It is shown that those procedures, most of which come from statistical nonlinear regression theory, are invaluable in interpreting errors in precipitation-runoff modeling and in identifying appropriate calibration strategies.
Authors
Brent M. Troutman

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 significa
Authors
D.F. Goerlitz, D.E. Troutman, E.M. Godsy, B.J. Franks

Pyrolysis-mass spectrometry/pattern recognition on a well-characterized suite of humic samples

A suite of well-characterized humic and fulvic acids of freshwater, soil and plant origin was subjected to pyrolysis-mass spectrometry and the resulting data were analyzed by pattern recognition and factor analysis. A factor analysis plot of the data shows that the humic acids and fulvic acids can be segregated into two distinct classes. Carbohydrate and phenolic components are more pronounced in
Authors
P. MacCarthy, S.J. DeLuca, K.J. Voorhees, R. L. Malcolm, E.M. Thurman