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
Learn about our Featured Science Activities through our pages that highlight studies, publications, and results.
Filter Total Items: 4095
Tracer-dilution experiments and solute-transport simulations for a mountain stream, Saint Kevin Gulch, Colorado Tracer-dilution experiments and solute-transport simulations for a mountain stream, Saint Kevin Gulch, Colorado
No abstract available.
Authors
R. E. Broshears, K.E. Bencala, B. A. Kimball, Diane M. McKnight
Documentation of a computer program to simulate horizontal-flow barriers using the U.S. Geological Survey's modular three-dimensional finite-difference ground-water flow model Documentation of a computer program to simulate horizontal-flow barriers using the U.S. Geological Survey's modular three-dimensional finite-difference ground-water flow model
No abstract available.
Authors
Paul A. Hsieh, John R. Freckleton
New reference materials for nitrogen-isotope-ratio measurements New reference materials for nitrogen-isotope-ratio measurements
Three new reference materials were manufactured for calibration of relative stable nitrogen‐isotope‐ratio measurements: USGS25 (ammonium sulfate) δ615″=−30 per mil USGS26 (ammonium sulfate) δ615″=+54 per mil USGS32 (potassium nitrate) δ615″=+180 per mil where δN′, relative to atmospheric nitrogen, is an approximate value subject to change following interlaboratory comparisons. These...
Authors
J.K. Bohlke, C. J. Gwinn, T. B. Coplen
Spatial variability of triazine herbicides in the Lower Mississippi River Spatial variability of triazine herbicides in the Lower Mississippi River
No abstract available.
Authors
J. A. Moody, D. A. Goolsby
Distributions of pesticides and organic contaminants between water and suspended sediment, San Francisco Bay, California Distributions of pesticides and organic contaminants between water and suspended sediment, San Francisco Bay, California
Suspended-sediment and water samples were collected from San Francisco Bay in 1991 during low river discharge and after spring rains. All samples were analyzed for organophosphate, carbamate, and organochlorine pesticides; petroleum hydrocarbons; biomarkers; and polynuclear aromatic hydrocarbons. The objectives were to determine the concentrations of these contaminants in water and...
Authors
Joseph L. Domagalski, K.M. Kuivila
Computation of type curves for flow to partially penetrating wells in water-table aquifers Computation of type curves for flow to partially penetrating wells in water-table aquifers
Evaluation of Neuman's analytical solution for flow to a well in a homogeneous, anisotropic, water-table aquifer commonly requires large amounts of computation time and can produce inaccurate results for selected combinations of parameters. Large computation times occur because the integrand of a semi-infinite integral involves the summation of an infinite series. Each term of the series...
Authors
Allen F. Moench
Analysis of flow in an observation well intersecting a single fracture Analysis of flow in an observation well intersecting a single fracture
A semi-analytical model is developed to determine transmissivity and storativity from the interpretation of transient flow in an observation well due to pumping in a source well where the two wells are connected by a single fracture. Flow rate can be determined using a heat-pulse flowmeter located above the intersection of the fracture in the observation well. The results of a field...
Authors
P.A. Lapcevic, K.S. Novakowski, Frederick L. Paillet
Particulate organic matter in the San Francisco Bay estuary, California: Chemical indicators of its origin and assimilation into the benthic food web Particulate organic matter in the San Francisco Bay estuary, California: Chemical indicators of its origin and assimilation into the benthic food web
No abstract available.
Authors
J. E. Cloern, E. A. Canuel, S.M. Wienke
Agricultural chemical interchange between ground water and surface water, Cedar River basin, Iowa and Minnesota: A study description Agricultural chemical interchange between ground water and surface water, Cedar River basin, Iowa and Minnesota: A study description
A review of the data collected in the Cedar River basin, Iowa and Minnesota, indicates that atrazine is consistently detected in the main-stem river at concentrations greater than 0.10 microgram per liter even during periods of extended base flow. The primary source of atrazine in the river during these periods of base flow is not known. This study is designed to determine how atrazine...
Authors
P. J. Squillace, M. J. Liszewski, E.M. Thurman
Effects of small-scale vertical variations in well-screen inflow rates and concentrations of organic compounds on the collection of representative ground-water-quality samples Effects of small-scale vertical variations in well-screen inflow rates and concentrations of organic compounds on the collection of representative ground-water-quality samples
Because a water sample collected from a well is an integration of water from different depths along the well screen, measured concentrations can be biased if analyte concentrations are not uniform along the length of the well screen. The resulting concentration in the sample, therefore, is a function of variations in well-screen inflow rate and analyte concentration with depth. A...
Authors
Jacob Gibs, G. Allan Brown, Kenneth S. Turner, Cecilia L. MacLeod, James Jelinski, Susan A. Koehnlein
Data on chlorofluorocarbons (CCl3F and CCl2F2) as dating tools and hydrologic tracers in shallow ground water of the Delmarva Peninsula Data on chlorofluorocarbons (CCl3F and CCl2F2) as dating tools and hydrologic tracers in shallow ground water of the Delmarva Peninsula
No abstract available.
Authors
Niel Plummer, S.A. Dunkle, Eurybiades Busenberg
Diazinon concentrations in the Sacramento and San Joaquin Rivers and San Francisco Bay, California, February 1993 Diazinon concentrations in the Sacramento and San Joaquin Rivers and San Francisco Bay, California, February 1993
The distribution and possible biological effects of a dormant spray pesticide, diazinon, were examined by measuring pesticide concentrations and estimating toxicity using bioassays at a series of sites in the Sacramento-San Joaquin Delta and San Francisco Bay. Pulses of diazinon were observed in early February 1993 in the Sacramento and San Joaquin Rivers after heavy rains, with elevated
Authors
Kathryn Kuivila