Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
Filter Total Items: 4094
Hydrologic data from the study of acidic contamination in the Miami Wash-Pinal Creek area, Arizona, water years 1994-96
Since 1984, hydrologic data have been collected as part of a U.S. Geological Survey study of the occurrence and movement of acidic contamination in the aquifer and streams of the Pinal Creek drainage basin near Globe, Arizona. Ground-water data from that study are presented for water years 1994, 1995, and 1996 and include location, construction information, site plans, water levels, chemical and p
Authors
Alice D. Konieczki, Cory E. Angeroth
Stable isotope evidence for an atmospheric origin of desert nitrate deposits in northern Chile and southern California, U.S.A.
Natural surficial accumulations of nitrate-rich salts in the Atacama Desert, northern Chile, and in the Death Valley region of the Mojave Desert, southern California, are well known, but despite many geologic and geochemical studies, the origins of the nitrates have remained controversial. N and O isotopes in nitrate, and S isotopes in coexisting soluble sulfate, were measured to determine if some
Authors
J.K. Böhlke, G. E. Ericksen, K. Revesz
Bacterial oxidation of methyl bromide in Mono Lake, California
The oxidation of methyl bromide (MeBr) in the water column of Mono Lake, CA, was studied by measuring the formation of H14CO3 from [14C]MeBr. Potential oxidation was detected throughout the water column, with highest rates occurring in the epilimnion (5-12 m depth). The oxidation of MeBr was eliminated by filter-sterilization, thereby demonstrating the involvement of bacteria. Vertical profiles of
Authors
T.L. Connell, S.B. Joye, L.G. Miller, R.S. Oremland
Protistan communities in aquifers: A review
Eukaryotic microorganisms (protists) are a very important component of microbial communities inhabiting groundwater aquifers This is not unexpected when one considers that many protists feed heterotrophically, by means of either phagotrophy (bacterivory) or osmotrophy. Protistan numbers are usually low (
Authors
G. Novarino, A. Warren, H. Butler, G. Lambourne, A. Boxshall, J. Bateman, N.E. Kinner, R.W. Harvey, R.A. Mosse, B. Teltsch
Transport and recovery of bacteriophage PRD1 in a sand and gravel aquifer: Effect of sewage-derived organic matter
To test the effects of sewage-derived organic matter on virus attachment, 32P-labeled bacteriophage PRD1, linear alkylbenzene sulfonates (LAS), and tracers were injected into sewage-contaminated (suboxic, elevated organic matter) and uncontaminated (oxic, low organic matter) zones of an iron oxide-coated quartz sand and gravel aquifer on Cape Cod, MA. In the uncontaminated zone, 83% of the PRD1 we
Authors
A.P. Pieper, J. N. Ryan, Ronald W. Harvey, G.L. Amy, T.H. Illangasekare, D.W. Metge
Borehole sampling of fracture populations - compensating for borehole sampling bias in crystalline bedrock aquifers, Mirror Lake, Grafton County, New Hampshire
The clustering of orientations of hydraulically conductive fractures in bedrock at the Mirror Lake, New Hampshire fractured rock study site was investigated by comparing the orientations of fracture populations in two subvertical borehole arrays with those mapped on four adjacent subvertical roadcuts. In the boreholes and the roadcuts, the orientation of fracture populations appears very similar a
Authors
G.D. McDonald, Frederick L. Paillet, C.C. Barton, C. D. Johnson
Microorganisms as tracers in groundwater injection and recovery experiments: A review
Modern day injection and recovery techniques designed to examine the transport behavior of microorganisms in groundwater have evolved from experiments conducted in the late 1800s, in which bacteria that form red or yellow pigments were used to trace flow paths through karst and fractured- rock aquifers. A number of subsequent groundwater hydrology studies employed bacteriophage that can be injecte
Authors
R.W. Harvey
Agricultural chemicals in groundwater of the midwestern United States: Relations to land use
To determine the relations between land use and concentrations of selected agricultural chemicals (nitrate, atrazine residue [atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) + deethylatrazinc (2-amino-4-chloro-6-isopropylamino-s-triazine) + deisopropylatrazine (2-amino-4-chloro-6-ethylamino-s-triazine)], and alachlor residue [alachlor, [2-chloro-2′,6′-diethyl-N-(methoxymethyl) acetani
Authors
D.W. Kolpin
Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution
Fluid saturation, particle-size distribution, and porosity measurements were obtained from 269 core samples collected from six boreholes along a 90-m transect at a subregion of a crude-oil spill site, the north pool, near Bemidji, Minnesota. The oil saturation data, collected 11 years after the spill, showed an irregularly shaped oil body that appeared to be affected by sediment spatial variabilit
Authors
Leslie A. Dillard, Hedeff I. Essaid, William N. Herkelrath
Evaluation of unconfined-aquifer parameters from pumping test data by nonlinear least squares
Nonlinear least squares (NLS) with automatic differentiation was used to estimate aquifer parameters from drawdown data obtained from published pumping tests conducted in homogeneous, water-table aquifers. The method is based on a technique that seeks to minimize the squares of residuals between observed and calculated drawdown subject to bounds that are placed on the parameter of interest. The an
Authors
M. Heidari, A. Moench
Effect of flagellates on free-living bacterial abundance in an organically contaminated aquifer
Little is known about the role of protists in the saturated subsurface. Porous media microcosms containing bacteria and protists, were used to determine whether flagellates from an organically contaminated aquifer could substantively affect the number of free- living bacteria (FLB). When flagellates were present, the 3-40% maximum breakthrough of fluorescent y labelled FLB injected into the microc
Authors
N.E. Kinner, R.W. Harvey, M. Kazmierkiewicz-Tabaka
Effects of reduced wastewater phosphate concentrations in South San Francisco Bay
No abstract available.
Authors
S.W. Hager, L. E. Schemel