Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
Filter Total Items: 3787
Concentration history during pumping from a leaky aquifer with stratified initial concentration
Analytical and numerical solutions are employed to examine the concentration history of a dissolved substance in water pumped from a leaky aquifer. Many aquifer systems are characterized by stratification, for example, a sandy layer overlain by a clay layer. To obtain information about separate hydrogeologic units, aquifer pumping tests are often conducted with a well penetrating only one of the l
Authors
Daniel J. Goode, Paul A. Hsieh, Allen M. Shapiro, Warren W. Wood, Thomas F. Kraemer
A finite-volume Eulerian-Lagrangian Localized Adjoint Method for solution of the advection-dispersion equation
A new mass-conservative method for solution of the one-dimensional advection-dispersion equation is derived and discussed. Test results demonstrate that the finite-volume Eulerian-Lagrangian localized adjoint method (FVELLAM) outperforms standard finite-difference methods, in terms of accuracy and efficiency, for solute transport problems that are dominated by advection. For dispersion-dominated p
Authors
R. W. Healy, T.F. Russell
Spatial variability of triazine herbicides in the Lower Mississippi River
No abstract available.
Authors
J. A. Moody, D. A. Goolsby
Effects of climatic variations over 11 years on nitrate-nitrogen concentrations in the Raccoon River, Iowa
Nitrate-nitrogen (NO3-N) concentrations at public water supply intakes on the Des Moines and Raccoon Rivers in Iowa exceeded the maximum contaminant level (MCL) of 10 mg L-1 for public water supplies established by the USEPA for extended periods of time from March through early August 1990. The excessive NO3-N levels followed 2 yr of less-than normal precipitation in 1988 and 1989. The largest dai
Authors
K.J. Lucey, D. A. Goolsby
Assessing the effect of pesticides in agricultural runoff on aquatic life in the Sangamon River near Monticello, Illinois
Stream-water samples collected from a midwest stream, following a thunderstorm during May 1991 were toxic to water fleas (Ceriodaphnia dubia), but not fathead minnows (Pimephales promelas), or a bacterium (Photobacterium phosphoreum) or green alga (Selenastrum capricornutum). It was unlikely that the toxicity to the water fleas was caused by herbicides, but it may have been caused by insecticides.
Authors
R.H. Coupe, M.S. Henebry, M.R. Branham
Crude oil in a shallow sand and gravel aquifer—I. Hydrogeology and inorganic geochemistry
Changes in the distribution of inorganic solutes in a shallow ground water contaminated by crude oil document a series of geochemical reactions initiated by biodegradation of the oil. Upgradient of an oil body floating on the water table, oxidation of oil to carbonic acid dissolves carbonate minerals in the aquifer matrix. In this oxidized zone pH is depressed ∼1 pH unit, and the concentrations of
Authors
P.C. Bennett, D.E. Siegel, M.J. Baedecker, M. F. Hult
Using borehole geophysics and cross-borehole flow testing to define hydraulic connections between fracture zones in bedrock aquifers
Nearly a decade of intensive geophysical logging at fractured rock hydrology research sites indicates that geophysical logs can be used to identify and characterize fractures intersecting boreholes. However, borehole-to-borehole flow tests indicate that only a few of the apparently open fractures found to intersect boreholes conduct flow under test conditions. This paper presents a systematic appr
Authors
Frederick L. Paillet
A brief history of the American radium industry and its ties to the scientific community of its early twentieth century
Federally funded remedial action projects are presently underway in New Jersey and Colorado at sites containing 226Ra and other radionuclides from radium-uranium ore extraction plants that operated during the early twentieth century. They are but the latest chapter in the story of an American industry that emerged and perished in the span of three decades. Major extraction plants were established
Authors
E. R. Landa
Crude oil in a shallow sand and gravel aquifer-II. Organic geochemistry
Crude oil spilled from a pipeline break in a remote area of north-central Minnesota has contaminated a shallow glacial outwash aquifer. Part of the oil was sprayed over a large area to the west of the pipeline and part of it accumulated in an oil body that floats at the water table to the east of the point of discharge. Total dissolved organic carbon (TDOC) concentrations in shallow groundwater co
Authors
R.P. Eganhouse, M.J. Baedecker, I.M. Cozzarelli, G. R. Aiken, K. A. Thorn, T.F. Dorsey
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 experiment wer
Authors
P.A. Lapcevic, K.S. Novakowski, Frederick L. Paillet
Distribution and significance of dicarboxylic acid anions in oil field waters
No abstract available.
Authors
Y.K. Kharaka, G. Ambats, J.J. Thordsen