Publications
Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).
Filter Total Items: 4094
Comparison of nonlinear least squares and log transformation procedures for calculating volatilization coefficients
A nonlinear least squares procedure and a log transformation procedure for calculating first-order rate coefficients from experimental concentration-versus-time data were compared using laboratory measurements of the volatilization from water of 1,1,1-trichloroethane and 1,2-dichloroethane and the absorption of oxygen by water. Ratios of the nonlinear least squares to log transformation volatiliza
Authors
R. E. Rathbun, D. Y. Tai
Denitrification in San Francisco Bay intertidal sediments
The acetylene block technique was employed to study denitrification in intertidal estuarine sediments. Addition of nitrate to sediment slurries stimulated denitrification. During the dry season, sediment-slurry denitrification rates displayed Michaelis-Menten kinetics, and ambient NO3− + NO2− concentrations (≤26 μM) were below the apparent Km (50 μM) for nitrate. During the rainy season, when ambi
Authors
Ronald S. Oremland, Cindy Umberger, Charles W. Culbertson, Richard L. Smith
The impact of uncertainties in hydrologic measurement on phosphorus budgets and empirical models for two Colorado reservoirs.
Water budgets and related chemical budgets of aquatic ecosystems commonly are interpreted without reference to uncertainties resulting from errors of measurement. The importance of such uncertainties in the use and interpretation of the phosphorus budgets of two Colorado reservoirs was determined.
Authors
James W. LaBaugh, T. C. Winter
The role of bacterial exopolymer and suspended bacteria in the nutrition of the deposit-feeding clam, Macoma balthica
Significant removal and assimilation of suspended bacteria by M. balthica was observed within two days, although the low clearance rates suggested planktonic bacteria may not be among its major food sources.
Authors
R.W. Harvey, Samuel N. Luoma
Subsurface injection of treated sewage into a saline-water aquifer at St. Petersburg, Florida - Aquifer pressure buildup
The city of St. Petersburg has been testing subsurface injection of treated sewage into the Floridan aquifer as a means of eliminating discharge of sewage to surface waters and as a means of storing treated sewage for future nonpotable reuse. Treated sweage that had a mean chloride concentration of 170 milligrams per liter (mg/l) was injected through a single well for 12 months at a mean rate of 4
Authors
J.J. Hickey
A column technique for determining sorption of organic solutes on the lithological structure of aquifers
No abstract available.
Authors
D.F. Goerlitz
Rhodamine-WT dye losses in a mountain stream environment
A significant fraction of rhodamine WT dye was lost during a short term multitracer injection experiment in a mountain stream environment. The conservative anion chloride and the sorbing cation lithium were concurrently injected. In-stream rhodamine WT concentrations were as low as 45 percent of that expected, based on chloride data. Concentration data were available from shallow‘wells’dug near th
Authors
Kenneth E. Bencala, Ronald E. Rathburn, Alan P. Jackman, Vance C. Kennedy, Gary W. Zellweger, Ronald J. Avanzino
Effect of retorted-oil shale leachate on a blue-green alga (Anabaena flos-aquae)
In the event of the development of the large oil shale reserves of Colorado, Utah, and Wyoming, one of the main environmental concerns will be disposal of retorted-oil shale which will be generated in greater volume than the original volume oI the mined oil shale. Investigators have found that leachates of retorted-oil shale are alkaline and have large concentrations of dissolved solids, molybdenu
Authors
Diane M. McKnight, Wilfred E. Pereira, Colleen E. Rostad, Eric A. Stiles
Transport of reacting solutes in porous media: Relation between mathematical nature of problem formulation and chemical nature of reactions
Examples involving six broad reaction classes show that the nature of transport-affecting chemistry may have a profound effect on the mathematical character of solute transport problem formulation. Substantive mathematical diversity among such formulations is brought about principally by reaction properties that determine whether (1) the reaction can be regarded as being controlled by local chemic
Authors
Jacob Rubin
The influence of aquatic humic substance properties on trihalomethane potential
No abstract available.
Authors
B.G. Oliver, E.M. Thurman
Structural study of humic substances: New approaches and methods
No abstract available.
Authors
E.M. Thurman, R.L. Malcom
Terpenoid marker compounds derived from biogenic precursors in volcanic ash from Mount St. Helens, Washington
A volcanic-ash sample obtained after the 1980 eruption of Mount St. Helens, Washington, was analyzed for cyclic terpenoid organic compounds and polycyclic aromatic hydrocarbons using capillary gas chromatography-mass spectrometry-computer techniques. Various tricyclic diterpenoid acids and hydrocarbons were identified including dehydroabietic acid, dehydroabietin, dehydroabietane, simonellite, and
Authors
W. E. Pereira, Colleen E. Rostad