Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
Filter Total Items: 4094
Colloid particle sizes in the Mississippi River and some of its tributaries, from Minneapolis to below New Orleans
An on-board technique was developed that combined discharge-weighted pumping to a high-speed continuous-flow centrifuge for isolation of the particulate-sized material with ultrafiltration for isolation of colloid-sized material. In order to address whether these processes changed the particle sizes during isolation, samples of particles in suspension were collected at various steps in the isolati
Authors
C.E. Rostad, T.F. Rees, S.R. Daniel
Models of metal binding structures in fulvic acid from the Suwannee River, Georgia
Fulvic acid, isolated from the Suwannee River, Georgia, was assessed for its ability to bind Ca2+, Cd2+, Cu2+, Ni2+, and Zn2+ ions at pH 6 before and after extensive fractionation that was designed to reveal the nature of metal binding functional groups. The binding constant for Ca2+ ion had the greatest increase of all the ions in a metal binding fraction that was selected for intensive character
Authors
J. A. Leenheer, G.K. Brown, P. MacCarthy, S.E. Cabaniss
Methyl mercury dynamics in littoral sediments of a temperate seepage lake
The sites and rates of methyl mercury (MeHg) production and transport in littoral zone sediments were investigated at Pallette Lake in northern Wisconsin. In littoral areas where groundwater inflow occurs, sulfate supply from groundwater creates profiles of electron acceptors (sulfate) and donors (methane, sulfide) that are reversed from those found in sediments whose sulfate supply is delivered f
Authors
D. P. Krabbenhoft, C.C. Gilmour, J.M. Benoit, Christopher L. Babiarz, A.W. Andren, J.P. Hurley
Interaction between stream temperature, streamflow, and groundwater exchanges in alpine streams
Four alpine streams were monitored to continuously collect stream temperature and streamflow for periods ranging from a week to a year. In a small stream in the Colorado Rockies, diurnal variations in both stream temperature and streamflow were significantly greater in losing reaches than in gaining reaches, with minimum streamflow losses occurring early in the day and maximum losses occurring ear
Authors
James E. Constantz
Analysis of transient storage subject to unsteady flow: Diel flow variation in an Antarctic stream
Transport of dissolved material in streams and small rivers may be characterized using tracer-dilution methods and solute transport models. Recent studies have quantified stream/substream interactions using models of transient storage. These studies are based on tracer-dilution data obtained during periods of steady flow. We present a modeling framework for the analysis of transient storage in str
Authors
R.L. Runkel, Diane M. McKnight, E.D. Andrews
Impact of the 1993 flood on the distribution of organic contaminants in bed sediments of the Upper Mississippi River
The 1500 km Upper Mississippi River (UMR) consists of 29 navigation pools and can be divided into the upper reach (pools 1-4), the middle reach (pools 5-13), and the lower reach (pools 14-26). Comparison of composite bed sediment samples collected from the downstream third of 24 pools before and after the 1993 UMR flood provides fieldscale data on the effect of the flood on sediment organic compou
Authors
L. B. Barber, J.H. Writer
Strain IMB-1, a novel bacterium for the removal of methyl bromide in fumigated agricultural soils
A facultatively methylotrophic bacterium, strain IMB-1, that has been isolated from agricultural soil grows on methyl bromide (MeBr), methyl iodide, methyl chloride, and methylated amines, as well as on glucose, pyruvate, or acetate. Phylogenetic analysis of its 16S rRNA gene sequence indicates that strain IMB-1 classes in the alpha subgroup of the class Proteobacteria and is closely related to me
Authors
Hancock T.L. Connell, A.M. Costello, M.E. Lidstrom, R.S. Oremland
Modeling CO2 degassing and pH in a stream-aquifer system
Pinal Creek, Arizona receives an inflow of ground water with high dissolved inorganic carbon (57-75 mg/l) and low pH (5.8-6.3). There is an observed increase of in-stream pH from approximately 6.0-7.8 over the 3 km downstream of the point of groundwater inflow. We hypothesized that CO2 gas-exchange was the most important factor causing the pH increase in this stream-aquifer system. An existing tra
Authors
J. Choi, S.M. Hulseapple, M.H. Conklin, J. W. Harvey
PHRQCGRF, a computer program for graphical interpretation of PHREEQC geochemical transport simulations (PC only)
No abstract available.
Authors
Joseph Vrabel, Pierre D. Glynn
Studies of the San Francisco Bay, California, estuarine ecosystem: Regional monitoring program results, 1997
As part of a regional monitoring program, water samples were collected in the San Francisco Bay estuary during 20 cruises from January through November 1997. Conductivity, temperature, light attenuation, turbidity, oxygen, and in-vivo chlorophyll fluorescence were measured longitudinally and vertically in the main channel of the estuary from south of the Dumbarton Bridge in the southern part of th
Authors
Jelriza I. Baylosis, Brian E. Cole, James E. Cloern
Water velocities and the potential for the movement of bed sediments in Sinclair Inlet of Puget Sound, Washington
Sinclair Inlet is a small embayment of Puget Sound in the State of Washington. The inlet, about 6.5 kilometers long and 1.5 kilometers wide, is the site of Puget Sound Naval Shipyard. There are concerns that bed sediments in the inlet may have been contaminated as a result of activities at the shipyard, and that these sediments could be resuspended by tide- and wind-driven currents and transported
Authors
Jeffrey W. Gartner, E. A. Prych, G. B. Tate, D. A. Cacchione, R. T. Cheng, W.R. Bidlake, J.T. Ferreira
Chlorofluorocarbons, sulfur hexafluoride, and dissolved permanent gases in ground water from selected sites in and near the Idaho National Engineering and Environmental Laboratory, Idaho, 1994-97
From July 1994 through May 1997, the U.S. Geological Survey in cooperation with the
Department of Energy, sampled 86 wells completed in the Snake River Plain aquifer at and
near the Idaho N ationa1 Engineering and Environmental Laboratory (INEEL). The wells were
sampled for a variety of constituents including one- and two-carbon halocarbons.
Concentrations of dichlorodifluoromethane (CFC-12),
Authors
Eurybiades Busenberg, Niel Plummer, Roy C. Bartholomay, Julian E. Wayland