Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
Filter Total Items: 3746
Constraining the inferred paleohydrologic evolution of a deep unsaturated zone in the Amargosa Desert
Natural flow regimes in deep unsaturated zones of arid interfluvial environments are rarely in hydraulic equilibrium with near-surface boundary conditions imposed by present-day plant–soil–atmosphere dynamics. Nevertheless, assessments of water resources and contaminant transport require realistic estimates of gas, water, and solute fluxes under past, present, and projected conditions. Multimillen
Authors
Michelle Ann Walvoord, David A. Stonestrom, Brian J. Andraski, Robert G. Striegl
Comparison of 13 equations for determining evapotranspiration from a prairie wetland, Cottonwood Lake Area, North Dakota, USA
Evapotranspiration determined using the energy-budget method at a semi-permanent prairie-pothole wetland in east-central North Dakota, USA was compared with 12 other commonly used methods. The Priestley-Taylor and deBruin-Keijman methods compared best with the energy-budget values; mean differences were less than 0.1 mm d−1, and standard deviations were less than 0.3 mm d−1. Both methods require m
Authors
Donald O. Rosenberry, David L. Stannard, Thomas C. Winter, Margo L. Martinez
Response to comment on "A reservoir of nitrate beneath desert soils"
We appreciate the comment by Jackson et al. (1), which underscores two points made in our recent paper (2): (i) that desert subsoil nitrate (NO–3) inventories are spatially highly variable, and thereby warrant substantial measurement efforts to reduce uncertainty in global extrapolations, and (ii) that Chihuahuan Desert subsoil NO–3 inventories tend to be much smaller than inventories in other wes
Authors
Michelle Ann Walvoord, Fred M. Phillips, David A. Stonestrom, R. Dave Evans, Peter C. Hartsough, Brent D. Newman, Robert G. Striegl
Inhibition and enhancement of microbial surface colonization: the role of silicate composition
Classical treatment of cell attachment by models of filtration or coulombic attraction assumes that attachment of cells to mineral surfaces would be controlled by factors such as response to predation, collision efficiency, or coulombic attraction between the charged groups at the mineral and cell surfaces. In the study reported here, the passive model of attachment was investigated using a native
Authors
Jennifer A. Roberts
Monitored natural attenuation forum: A panel discussion
No abstract available.
Authors
Bruce E. Rittmann, Fran Kremer, Barbara Bekins
The microbial arsenic cycle in Mono Lake, California
Significant concentrations of dissolved inorganic arsenic can be found in the waters of a number of lakes located in the western USA and in other water bodies around the world. These lakes are often situated in arid, volcanic terrain. The highest concentrations of arsenic occur in hypersaline, closed basin soda lakes and their remnant brines. Although arsenic is a well-known toxicant to eukaryotes
Authors
Ronald S. Oremland, John F. Stolz, James T. Hollibaugh
Uranium mill tailings: Nuclear waste and natural laboratory for geochemical and radioecological investigations
Uranium mill tailings (UMT) are a high volume, low specific activity radioactive waste typically disposed in surface impoundments. This review focuses on research on UMT and related earth materials during the past decade relevant to the assessment of: (1) mineral hosts of radionuclides; (2) the use of soil analogs in predicting long-term fate of radionuclides; (3) microbial and diagenetic processe
Authors
Edward R. Landa
Hydraulic and geochemical framework of the Idaho National Engineering and Environmental Laboratory vadose zone
Questions of major importance for subsurface contaminant transport at the Idaho National Engineering and Environmental Laboratory (INEEL) include (i) travel times to the aquifer, both average or typical values and the range of values to be expected, and (ii) modes of contaminant transport, especially sorption processes. The hydraulic and geochemical framework within which these questions are addre
Authors
John R. Nimmo, Joseph P. Rousseau, Kim S. Perkins, Kenneth G. Stollenwerk, Pierre D. Glynn, Roy C. Bartholomay, LeRoy L. Knobel
"Implications of Observed and Simulated Ambient Flow in Monitoring Wells,” by Alper Elci, Fred J. Molz III, and W. R. Waldrop, November-December 2001 issue, v. 39, no. 6: 853–862
No abstract available.
Authors
Fredrick L. Paillet
Effect of Fe(III) on 1,1,2,2-Tetrachloroethane degradation and vinyl chloride accumulation in wetland sediments of the Aberdeen Proving Ground
1,1,2,2-Tetrachloroethane (TeCA) contaminated groundwater at the Aberdeen Proving Ground discharges through an anaerobic wetland in West Branch Canal Creek (MD), where dechlorination occurs. Two microbially mediated pathways, dichloroelimination and hydrogenolysis, account for most of the TeCA degradation at this site. The dichloroelimination pathways lead to the formation of vinyl chloride (VC),
Authors
Elizabeth Jones, Mary Voytek, Michelle Lorah
In situ expression of nifD in Geobacteraceae in subsurface sediments
In order to determine whether the metabolic state of Geobacteraceae involved in bioremediation of subsurface sediments might be inferred from levels of mRNA for key genes, in situ expression of nifD, a highly conserved gene involved in nitrogen fixation, was investigated. When Geobacter sulfurreducens was grown without a source of fixed nitrogen in chemostats with acetate provided as the limiting
Authors
Dawn E. Holmes, Kelly P. Nevin, Derek R. Lovely
Use of PRD1 bacteriophage in groundwater viral transport, inactivation, and attachment studies
PRD1, an icosahedra-shaped, 62 nm (diameter), double-stranded DNA bacteriophage with an internal membrane, has emerged as an important model virus for studying the manner in which microorganisms are transported through a variety of groundwater environments. The popularity of this phage for use in transport studies involving geologic media is due, in part, to its relative stability over a range of
Authors
Ronald W. Harvey, Joseph N. Ryan