Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
Filter Total Items: 4094
Soil, plant, and structural considerations for surface barriers in arid environments: Application of results from studies in the Mojave Desert near Beatty, Nevada
The suitability of a waste-burial site depends on hydrologic processes that can affect the near-surface water balance. In addition, the loss of burial trench integrity by erosion and subsidence of trench covers may increase the likelihood of infiltration and percolation, thereby reducing the effectiveness of the site in isolating waste. Although the main components of the water balance may be defi
Authors
Brian J. Andraski, David E. Prudic
Analysis of the Cape Cod tracer data
An analysis of the Cape Cod test was performed using several first- and higher-order theoretical models. We compare conditional and unconditional solutions of the transport equation and employ them for analysis of the experimental data. We consider spatial moments, mass breakthrough curves, and the distribution of the solute mass in space. The concentration measurements were also analyzed using th
Authors
Souheil Ezzedine, Yoram Rubin
Tritium/3He dating of river infiltration: An example from the Danube in the Szigetköz area, Hungary
3H, He, 4He, and Ne data were obtained from a shallow ground-water system being recharged by bank infiltration from the Danube River in northwestern Hungary. After correting for excess air, 4He and Ne concentrations reflect a recharge temperature of about 9° C., close to the mean annual temperature of the Danube (10.4° C). Values of H plus 3Hetrit (“initial tritium”) as a function of the tritium/H
Authors
M. Stute, J. Deák, K. Révész, J. K. Böhlke, E. Deseö, R. Weppernig, P. Schlosser
Potential for intrinsic bioremediation of a DNT-contaminated aquifer
Microorganisms indigenous to a shallow aquifer, which underlies an explosives-contaminated site, mineralized 28% of [U-ring-14C] 2,4–dinitrotoluene to 14CO2 within 28 days under aerobic conditions. Approximately 20% of added 2,4–dinitrotoluene remained undegraded at the end of the incubation while approximately 22% and 6% were transformed to 4–amino-2–nitrotoluene and 2–amino-4–nitrotoluene, respe
Authors
P. M. Bradley, F. H. Chapelle, J. E. Landmeyer, J.G. Schumacher
Deep well injection of brine from Paradox Valley, Colorado: Potential major precipitation problems remediated by nanofiltration
Groundwater brine seepage into the Dolores River in Paradox Valley, Colorado, increases the dissolved solids load of the Colorado River annually by ∼2.0 × 108 kg. To abate this natural contamination, the Bureau of Reclamation plans to pump ∼3540 m3/d of brine from 12 shallow wells located along the Dolores River. The brine, with a salinity of 250,000 mg/L, will be piped to the deepest (4.9 km) dis
Authors
Yousif K. Kharaka, Gil Ambats, James J. Thordsen, Roy A. Davis
Quantifying macropore recharge: Examples from a semi-arid area
The purpose of this paper is to illustrate the significantly increased resolution of determining macropore recharge by combining physical, chemical, and isotopic methods of analysis. Techniques for quantifying macropore recharge were developed for both small-scale (1 to 10 km2) and regional-scale areas in and semi-arid areas. The Southern High Plains region of Texas and New Mexico was used as a re
Authors
W.W. Wood, Ken A. Rainwater, D.B. Thompson
Binding of pyrene to aquatic and commercial humic substances: The role of molecular weight and aromaticity
The binding of pyrene to a number of humic substances isolated from various aquatic sources and a commercial humic acid was measured using the solubility enhancement method. The humic materials used in this study were characterized by various spectroscopic and liquid chromatography methods. A strong correlation was observed between the pyrene binding coefficient, K(doc), and the molecular weights,
Authors
Y.-P. Chin, G. R. Aiken, K.M. Danielsen
Fractured-aquifer hydrogeology from geophysical logs; the passaic formation, New Jersey
The Passaic Formation consists of gradational sequences of mudstone, siltstone, and sandstone, and is a principal aquifer in central New Jersey. Ground‐water flow is primarily controlled by fractures interspersed throughout these sedimentary rocks and characterizing these fractures in terms of type, orientation, spatial distribution, frequency, and transmissivity is fundamental towards understandi
Authors
R. H. Morin, G.B. Carleton, S. Poirier
Temporal trends of selected agricultural chemicals in Iowa's groundwater, 1982-1995: Are things getting better?
Since 1982, the Iowa Groundwater Monitoring (IGWM) Program has been used to sample untreated groundwater from Iowa municipal wells for selected agricultural chemicals. This long-term database was used to determine if concentrations of select agricultural chemicals in groundwater have changed with time. Nitrate, alachlor [2-chloro-2′-6′-diethyl-N-(methoxymethyl)-acetanilide], atrazine (2-chloro-4-e
Authors
D.W. Kolpin, D. Sneck-Fahrer, G.R. Hallberg, R.D. Libra
Modeling structural influences on soil water retention
A new model quantities the effect of soil structure, considered as the arrangement of particles in the soil, on soil water retention. The model partitions the pore space into texture-related and structure-related components, the textural component being what can be deduced to exist if the arrangement of the particles were random, and the structural component being the remainder. An existing model,
Authors
J. R. Nimmo
From the 1988 drought to the 1993 flood: Transport of halogenated organic compounds with the Mississippi river suspended sediment at Thebes, Illinois
Suspended sediment was isolated from water samples collected from the Mississippi River at Thebes, IL, eight times over a 5-year period from May 1988 through September 1993 in order to evaluate the transport of lipophilic halogenated organic compounds associated with the suspended sediment. Two hydrologic extremes were included-the 1988 drought and the 1993 flood. Halogenated organic compounds inc
Authors
C.E. Rostad
Experimental design for estimating parameters of rate-limited mass transfer: Analysis of stream tracer studies
Tracer experiments are valuable tools for analyzing the transport characteristics of streams and their interactions with shallow groundwater. The focus of this work is the design of tracer studies in high-gradient stream systems subject to advection, dispersion, groundwater inflow, and exchange between the active channel and zones in surface or subsurface water where flow is stagnant or slow movin
Authors
Brian J. Wagner, Judson W. Harvey