Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
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Molecular weight, polydispersity, and spectroscopic properties of aquatic humic substances
The number- and weight-averaged molecular weights of a number of aquatic fulvic acids, a commercial humic acid, and unfractionated organic matter from four natural water samples were measured by high-pressure size exclusion chromatography (HPSEC). Molecular weights determined in this manner compared favorably with those values reported in the literature. Both recent literature values and our data
Authors
Y.-P. Chin, G. Aiken, E. O'Loughlin
Sorption of chlorobenzenes to cape cod aquifer sediments
Sorption of tetra- and pentachlorobenzene by sediment from a glacial outwash aquifer on Cape Cod, MA, was evaluated. Particle size and mineralogical fractions (separated based on paramagnetic susceptibility) were characterized with respect to sediment organic carbon (SOC), mineralogy, surface area, metal oxide coatings, and spatial variability. SOC increases by a factor of 10 as particle size decr
Authors
L.B. Barber
Estimates of percolation rates and ages of water in unsaturated sediments at two Mojave Desert sites, California-Nevada
Thick unsaturated zones in arid regions increasingly are being sought for the burial of radioactive and other hazardous wastes. Estimating percolation rates of water from precipitation at proposed burial sites is important for site assessment. Chloride profiles in unsaturated sediments are used to show differences and similarities in the rates of percolation at two sites in the Mojave Desert of so
Authors
David E. Prudic
An interactive code (NETPATH) for modeling NET geochemical reactions along a flow PATH, version 2.0
NETPATH is an interactive Fortran 77 computer program used to interpret net geochemical mass-balance reactions between an initial and final water along a hydrologic flow path. Alternatively, NETPATH computes the mixing proportions of two to five initial waters and net geochemical reactions that can account for the observed composition of a final water. The program utilizes previously defined chemi
Authors
Niel Plummer, Eric C. Prestemon, David L. Parkhurst
Application of borehole geophysics in the characterization of flow in fractured rocks
No abstract available.
Authors
Frederick L. Paillet
Analysis of the results of hydraulic-fracture stimulation of two crystalline bedrock boreholes, Grand Portage, Minnesota
Hydraulic fracture-stimulation procedures typical of those provided by contractors in the water-well industry were applied to two boreholes in basaltic and gabbroic rocks near Grand Portage, Minnesota.These boreholes were considered incapable of supplying adequate ground water for even a single household although geophysical logs showed both boreholes were intersected by many apparently permeable
Authors
Fredrick L. Paillet, James D. Olson
Hydrogeology and hydrologic system of Pinal Creek Basin, Gila County, Arizona
Acidic water that contains elevated concentrations of metals has contaminated a stream and alluvial aquifer in a mining district near Globe, Arizona. The contaminated aquifer is a narrow layer of unconsolidated alluvium along Miami Wash and Pinal Creek. The alluvium overlies basin fill, which extends throughout most of the Pinal Creek basin. The alluvium and basin fill compose the primary aquifer
Authors
C.C. Neaville, J. G. Brown
Geohydrology and ground-water quality in the vicinity of a ground-water-contamination site in Rockford, Illinois
A geohydrologic investigation was performed by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, to determine the distribution of volatile organic compounds in a fractured-rock aquifer near the Southeast Rockford Groundwater Contamination Site in Rockford, Ill. The geologic units of concern are the St. Peter Sandstone and Glenwood Formation; the dolomites of
Authors
R. T. Kay, S. T. Prinos, Frederick L. Paillet
Organic compounds downstream from a treated-wastewater discharge near Dallas, Texas, March 1987
Water and streambed-sediment samples were collected on March 9 and 10,1987 from one site upstream and three sites downstream of the discharge from a municipal wastewater-treatment plant on Rowlett Creek near Dallas, Texas. To extract and separate organic compounds, purgeand-trap, closed-loop stripping, and pH-adjusted solvent extraction methods were used for water samples; and a Soxhlet-solvent ex
Authors
P.M. Buszka, L.B. Barber, M.P. Schroeder, L.D. Becker
Distribution and transport of selected anthropogenic organic compounds on Mississippi River suspended sediment (U.S.A.), May/June 1988
The distribution and transport of selected hydrophobic halogenated organic compounds on suspended sediment from the lower Mississippi River were determined using discharge-weighted sampling with concurrent discharge measurements. Trends in compound concentration from upstream to downstream and the effects of selected tributaries were determined. The compounds identified on the suspended sediment i
Authors
C.E. Rostad, W. E. Pereira, T.J. Leiker
Chemistry of manganese precipitation in Pinal Creek, Arizona, USA: A laboratory study
Groundwater underlying the valley of Pinal Creek downstream from Globe, Arizona, has been contaminated by low-pH metal-enriched wastewater from copper mining and ore processing at Miami, Arizona. At present, the acidity and most of the dissolved metal content, except for Mn, of the wastewater is removed by reactions with carbonate and other solids in the alluvial aquifer before the neutralized con
Authors
J. D. Hem, Carol J. Lind
Genetic population structure of the recently introduced Asian clam, Potamocorbula amurensis, in San Francisco Bay
The genetic population structure of the recently introduced Asian clam, Potamocorbula amurensis, in San Francisco Bay was described using starch gel electrophoresis at eight presumptive loci. Specimens were taken from five environmentally distinct sites located throughout the bay. The population maintains a high degree of genetic variation, with a mean heterozygosity of 0.295, a mean polymorphism
Authors
T. F. Duda