Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
GeoHEALTH-USGS Newsletter
GeoHEALTH-USGS Newsletter
The GeoHEALTH–USGS Newsletter—published since 2004—provides information on USGS science activities pertinent to safeguarding the health of fish, wildlife, domesticated animals, and people from environmental exposures to contaminants and pathogens.
Featured Science Activities
Featured Science Activities
Lean about our Featured Science Activities through our pages that highlight science studies, publications, and results.
Filter Total Items: 3785
Testing a method-of-characteristics model of three-dimensional solute transport in ground water Testing a method-of-characteristics model of three-dimensional solute transport in ground water
A new three-dimensional model of solute transport in groundwater that is based on a widely used two-dimensional method of characteristics model and is coupled to a modular finite-difference flow model is under development. The model's accuracy for ideal aquifers having homogeneous properties, uniform boundary conditions, and steady flow along a grid direction is demonstrated by...
Authors
Daniel J. Goode, Leonard F. Konikow
Geochemistry of dissolved inorganic carbon in a Coastal Plain aquifer. 1. Sulfate from confining beds as an oxidant in microbial CO2 production Geochemistry of dissolved inorganic carbon in a Coastal Plain aquifer. 1. Sulfate from confining beds as an oxidant in microbial CO2 production
A primary source of dissolved inorganic carbon (DIC) in the Black Creek aquifer of South Carolina is carbon dioxide produced by microbially mediated oxidation of sedimentary organic matter. Groundwater chemistry data indicate, however, that the available mass of inorganic electron acceptors (oxygen, Fe(III), and sulfate) and observed methane production is inadequate to account for...
Authors
F. H. Chapelle, P.B. McMahon
Selectivity and effectiveness of extractants used to release metals associated with organic matter Selectivity and effectiveness of extractants used to release metals associated with organic matter
Partial extraction procedures can be used to release metals associated with organic matter in natural materials. Reagents commonly employed for this purpose include hydrogen peroxide, Na hypochlorite and Na pyrophosphate. This study tested the selectivity of these reagents by comparing the amount of Fe, Mn, Zn and Cu they released from sulfide and oxide minerals and determined the...
Authors
C. S.E. Papp, L.H. Filipek, K. S. Smith
Coprecipitation mechanisms and products in manganese oxidation in the presence of cadmium Coprecipitation mechanisms and products in manganese oxidation in the presence of cadmium
Manganese oxidation products were precipitated in an aerated open-aqueous system where a continuous influx of mixed Mn2+ and Cd2+ solution was supplied and pH was maintained with an automated pH-stat adding dilute NaOH. X-ray diffraction and electron diffraction identified the solids produced as mixtures of Cd2Mn34+O8, Mn2+2Mn4+3O8, MnO2 (ramsdellite), and CdCO3. Mean oxidation numbers...
Authors
J.D. Hem, Carol J. Lind
Use of colloid filtration theory in modeling movement of bacteria through a contaminated sandy aquifer Use of colloid filtration theory in modeling movement of bacteria through a contaminated sandy aquifer
\A filtration model commonly used to describe removal of colloids during packed-bed filtration in water treatment applications was modified for describing downgradient transport of bacteria in sandy, aquifer sediments. The modified model was applied to the results of a small-scale (7 m), natural-gradient tracer test and to observations of an indigenous bacterial population moving...
Authors
R.W. Harvey, S. P. Garabedian
Herbicides in surface waters of the midwestern United States: The effect of spring flush Herbicides in surface waters of the midwestern United States: The effect of spring flush
Approximately three-fourths of all preemergent herbicides used in the United States are applied to row crops over a 12-state area, called the "corn belt" (I). The application of these compounds may cause widespread degradation of water quality (2). Because herbicides are water soluble, there is the potential for leaching into groundwater and surface water (3, 4), as well as aerial...
Authors
E.M. Thurman, D. A. Goolsby, M. T. Meyer, D.W. Kolpin
Convergent radial dispersion: A note on evaluation of the Laplace transform solution Convergent radial dispersion: A note on evaluation of the Laplace transform solution
A numerical inversion algorithm for Laplace transforms that is capable of handling rapid changes in the computed function is applied to the Laplace transform solution to the problem of convergent radial dispersion in a homogeneous aquifer. Prior attempts by the author to invert this solution were unsuccessful for highly advective systems where the Peclet number was relatively large. The...
Authors
Allen F. Moench
Plan to evaluate the effects of hydrogeologic conditions and human activities on water quality in the coastal plain of New York and New Jersey Plan to evaluate the effects of hydrogeologic conditions and human activities on water quality in the coastal plain of New York and New Jersey
No abstract available.
Authors
E. F. Vowinkel, S. F. Siwiec
Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Klamath Basin, California and Oregon, 1988-89 Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Klamath Basin, California and Oregon, 1988-89
No abstract available.
Authors
S. K. Sorenson, S.E. Schwarzbach
A steady-state unsaturated-zone model to simulate pesticide transport A steady-state unsaturated-zone model to simulate pesticide transport
No abstract available.
Authors
A. T. Rutledge, J. O. Helgesen
Preliminary geologic and hydrologic evaluation of a small watershed near Plains, Georgia Preliminary geologic and hydrologic evaluation of a small watershed near Plains, Georgia
No abstract available.
Authors
D.W. Hicks, James B. McConnell, Loris E. Asmussen
Distribution of selected herbicides and nitrate in the Mississippi River and its major tributaries, April through June 1991 Distribution of selected herbicides and nitrate in the Mississippi River and its major tributaries, April through June 1991
No abstract available.
Authors
D. A. Goolsby, R.C. Coupe, D.J. Markovchick