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Publications

Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).

Filter Total Items: 3740

Spatial variation in hydraulic conductivity determined by slug tests in the Canadian River alluvium near the Norman Landfill, Norman, Oklahoma

Slug tests were used to characterize hydraulic conductivity variations at a spatial scale on the order of meters in the alluvial aquifer downgradient of the Norman Landfill. Forty hydraulic conductivity measurements were made, most along a 215-meter flow path transect. Measured hydraulic conductivity, excluding clayey layers, ranged from 8.4 x 10-7 to 2.8 x 10-4 meters per second, with a median va
Authors
Martha A. Scholl, Scott C. Christenson

Tritium in unsaturated zone gases and air at the Amargosa Desert Research Site, and in spring and river water, near Beatty, Nevada, May 1997

Elevated tritium concentrations in the unsaturated zone at the Amargosa Desert Research Site (ADRS), immediately south and west of the low-level radioactive-waste burial site south of Beatty, Nevada, have stimulated research of processes that control the transport of tritium in arid unsaturated zones. In May 1997, 58 samples were collected from 1.5 m (meters) depth within a 250 m by 250 m grid at
Authors
Robert G. Striegl, Richard W. Healy, Robert L. Michel, David E. Prudic

Anaerobic oxidation of [1,2-14C]Dichloroethene under Mn(IV)-reducing conditions

Anaerobic oxidation of [1,2-14C]dichloroethene to14CO2 under Mn(IV)-reducing conditions was demonstrated. The results indicate that oxidative degradation of partially chlorinated solvents like dichloroethene can be significant even under anoxic conditions and demonstrate the potential importance of Mn(IV) reduction for remediation of chlorinated groundwater contaminants.
Authors
Paul M. Bradley, James Landmeyer, Richard S. Dinicola

Sources and age of aquatic humus

As aquatic scientists have recognized the diversity of processes controlled by or dependent upon aquatic humus, it has become important to learn more about the genesis, chemical properties, and concentration of humic substances in aquatic ecosystems. There are three classes of aquatic humus (fulvic acids, humic acids, and humin), all of which share the characteristics of being heterogeneous biomol
Authors
Diane M. McKnight, George R. Aiken

Predictive double-layer modeling of metal sorption in mine-drainage systems

Previous comparison of predictive double-layer modeling and empirically derived metal-partitioning data has validated the use of the double-layer model to predict metal sorption reactions in iron-rich mine-drainage systems. The double-layer model subsequently has been used to model data collected from several mine-drainage sites in Colorado with diverse geochemistry and geology. This work demonstr
Authors
K. S. Smith, J. F. Ranville, D.L. Macalady

Fundamentals of isotope geochemistry

The dominant use of isotopes in catchment research in the last few decades has been to trace sources of waters and solutes. Generally, such data were evaluated with simple mixing models to determine how much was derived from either of the two (sometimes three) constant-composition sources. This chapter illustrates the environmental isotopes that are natural and anthropogenic isotopes whose wide di
Authors
Carol Kendall, Eric A. Caldwell