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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: 3746

Environmental factors affecting mercury in Camp Far West Reservoir, California, 2001-03

This report documents water quality in Camp Far West Reservoir from October 2001 through August 2003. The reservoir, located at approximately 300 feet above sea level in the foothills of the northwestern Sierra Nevada, California, is a monomictic lake characterized by extreme drawdown in the late summer and fall. Thermal stratification in summer and fall is coupled with anoxic conditions in the hy
Authors
Charles N. Alpers, A. Robin Stewart, Michael K. Saiki, Mark C. Marvin-DiPasquale, Brent R. Topping, Kelly M. Rider, Steven K. Gallanthine, Cynthia A. Kester, Robert O. Rye, Ronald C. Antweiler, John F. De Wild

Effects of nitrate and water on the oxygen isotopic analysis of barium sulfate precipitated from water samples

BaSO4 precipitated from mixed salt solutions by common techniques for SO isotopic analysis may contain quantities of H2O and NO that introduce errors in O isotope measurements. Experiments with synthetic solutions indicate that δ18O values of CO produced by decomposition of precipitated BaSO4 in a carbon reactor may be either too low or too high, depending on the relative concentrations of SO and
Authors
Janet E. Hannon, John K. Böhlke, Stanley J. Mroczkowski

Simulated response of water quality in public supply wells to land use change

Understanding how changes in land use affect water quality of public supply wells (PSW) is important because of the strong influence of land use on water quality, the rapid pace at which changes in land use are occurring in some parts of the world, and the large contribution of groundwater to the global water supply. In this study, groundwater flow models incorporating particle tracking and reacti
Authors
P. B. McMahon, K.R. Burow, L. J. Kauffman, S. M. Eberts, J.K. Böhlke, J.J. Gurdak

Utilization of protein expression profiles as indicators of environmental impairment of smallmouth bass (Micropterus dolomieu) from the Shenandoah River, Virginia, USA

The Shenandoah River (VA, USA), the largest tributary of the Potomac River (MD, USA) and an important source of drinking water, has been the site of extensive fish kills since 2004. Previous investigations indicate environmental stressors may be adversely modulating the immune system of smallmouth bass (Micropterus dolomieu) and other species. Anterior kidney (AK) tissue, the major site of blood c
Authors
J. Ripley, L. Iwanowicz, V. Blazer, C. Foran

A national reconnaissance for pharmaceuticals and other organic wastewater contaminants in the United States - II) Untreated drinking water sources

Numerous studies have shown that a variety of manufactured and natural organic compounds such as pharmaceuticals, steroids, surfactants, flame retardants, fragrances, plasticizers and other chemicals often associated with wastewaters have been detected in the vicinity of municipal wastewater discharges and livestock agricultural facilities. To provide new data and insights about the environmental
Authors
M. J. Focazio, D.W. Kolpin, K.K. Barnes, E. T. Furlong, M. T. Meyer, S.D. Zaugg, L. B. Barber, M.E. Thurman

Method for estimating spatially variable seepage loss and hydraulic conductivity in intermittent and ephemeral streams

A method is presented for estimating seepage loss and streambed hydraulic conductivity along intermittent and ephemeral streams using streamflow front velocities in initially dry channels. The method uses the kinematic wave equation for routing streamflow in channels coupled to Philip's equation for infiltration. The coupled model considers variations in seepage loss both across and along the chan
Authors
R.G. Niswonger, David E. Prudic, G.E. Fogg, David A. Stonestrom, E.M. Buckland

Microbial and chemical factors influencing methane production in laboratory incubations of low-rank subsurface coals

Lignite and subbituminous coals were investigated for their ability to support microbial methane production in laboratory incubations. Results show that naturally-occurring microorganisms associated with the coals produced substantial quantities of methane, although the factors influencing this process were variable among different samples tested. Methanogenic microbes in two coals from the Powder
Authors
Stephen H. Harris, Richard L. Smith, Charles E. Barker

Photoreduction fuels biogeochemical cycling of iron in Spain's acid rivers

A number of investigations have shown that photoreduction of Fe(III) causes midday accumulations of dissolved Fe(II) in rivers and lakes, leading to large diel (24-h) fluctuations in the concentration and speciation of total dissolved iron. Less well appreciated is the importance of photoreduction in providing chemical energy for bacteria to thrive in low pH waters. Diel variations in water chemis
Authors
C.H. Gammons, D. A. Nimick, S.R. Parker, D.M. Snyder, R. Blaine McCleskey, R. Amils, S.R. Poulson

Electrical characterization of non‐Fickian transport in groundwater and hyporheic systems

Recent work indicates that processes controlling solute mass transfer between mobile and less mobile domains in porous media may be quantified by combining electrical geophysical methods and electrically conductive tracers. Whereas direct geochemical measurements of solute preferentially sample the mobile domain, electrical geophysical methods are sensitive to changes in bulk electrical conductivi
Authors
Kamini Singha, Adam Pidlisecky, Frederick D. Day-Lewis, Michael N. Gooseff

Concentrations and environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks and accumulation in sludge, New Jersey Coastal Plain, USA

Concentrations of Ra in liquid and solid wastes generated from 15 softeners treating domestic well waters from New Jersey Coastal Plain aquifers (where combined Ra (226Ra plus 228Ra) concentrations commonly exceed 0.185 Bq L−1) were determined. Softeners, when maintained, reduced combined Ra about 10-fold (<0.024 Bq L−1). Combined Ra exceeded 0.185 Bq L−1 at 1 non-maintained system. Combined Ra wa
Authors
Z. Szabo, E. Jacobsen, T. F. Kraemer, B. Parsa

In situ arsenic removal in an alkaline clastic aquifer

In situ removal of As from ground water used for water supply has been accomplished elsewhere in circum-neutral ground water containing high dissolved Fe(II) concentrations. The objective of this study was to evaluate in situ As ground-water treatment approaches in alkaline ground-water (pH > 8) that contains low dissolved Fe (<a few tens of μg/L). The low dissolved Fe content limits development o
Authors
A. H. Welch, K.G. Stollenwerk, A.P. Paul, D. K. Maurer, K. J. Halford

Cross-borehole flow tests and insights into hydraulic connections in fractured mudstone and sandstone

Cross-borehole flow tests provided insights into hydraulic connections in fractured and dipping mudstone and sandstone that were consistent with the lithostratigraphic and structural framework of a VOCcontaminated bedrock research site in west-central New Jersey. Two cross-borehole flow tests were completed. Each test involved measurement and analysis of transient flow in a newly installed deep co
Authors
John H. Williams, Pierre Lacombe, Carole D. Johnson, Frederick L. Paillet