Simulation of Reactive Chemical Transport in a Varying Thermal Field with Reaction-Flow Coupling
A computer program, THCVP, simulates coupling between advective/diffusive solute transport and chemical reactions, coupling of the reactions to heat transport, and feedback from precipitation/dissolution...
Three-Dimensional Plume Dynamics in the Vadose Zone: PORFLO-3 Modeling of a Defense Waste Leak at Hanford
In 1973, approximately 450 m3 of liquid containing radioactive and chemical wastes leaked from the 241-T-106 single-shell tank into the vadose zone...
Geochemical Modeling: An Integrated Approach to Nuclear Waste Disposal Issues
To meet nuclear waste repository licensing requirements, the response of repository components and of the enclosing host rocks and fluids to temperature fluctuations, fluid flow, radionuclide...
Properties of the West Valley Waste Form
The centroid composition of the West Valley Demonstration Project waste form has been selected on the basis of criteria mandating high chemical durability and good processibility. A review...
Characteristics of Potential Repository Wastes
The U.S. Department of Energy is responsible for the eventual disposal in a repository of spent fuels, high-level waste, and other radioactive wastes that may require long-term isolation....
Effects of Water Composition on the Dissolution Rate of UO2 Under Oxidizing Conditions
Dissolution rates were measured on crushed unirradiated UO2 fuel pellet samples under oxidizing conditions using a flow-through testing method. Water...
Renovating the Riverside Water Plant?A Case Study
In 1986, the City of Waco, Texas began construction of the first of four projects designed to renovate the Riverside Water Treatment Plant. The water treatment plant was originally constructed...
A Rational Basis for Determining Safety of Containment
Design of waste containment facilities may follow one of three tacts: (1) the liner and cover systems may have prescribed components of predetermined minimum thicknesses and hydraulic...
Effects & Risk Analysis for Time Variable Exposures
The effects of toxicants on organisms in natural settings are a function of both the variations in exposure concentrations and duration of exposure. This paper present analysis procedures...
Unmixing Mixed Waste
A thermal treatment process successfully converted sludge classified as hazardous chemical/radioactive mixed waste to low specific activity radioactive waste at the National Guard Armory...
Vaporizing VOCs
The authors summarize the findings of a study for the Environmental Protection Agency on vapor extraction of volatile organic compounds from soils. The potential for ground water contamination...
Remediating A Fire Site
Machin and Ehresmann describe remediation of a 15 acre fire site at Fort Huachuca, Ariz. An investigation after the fire showed that all of the debris contained asbestos. Sampling confirmed...
Calibration of a Transport Model Using Halocarbons
A field study was conducted during April 1987 in which the concentrations of volatile halocarbon tracers, discharged from two existing outfalls, were measured throughout Boston Harbor...
Factors Affecting Neutron Gauge Calibration
Neutron gauge characteristics and soil chemistry affect gauge calibration. External factors also influence gauge calibration and should be considered in the calibration procedure. Gauge...
Relationship of Soil Type and Chemicals to the Calibration of Neutron Meters
Theory of neutron scattering and moderation in matter explains many of the characteristics of calibration curves of neutron moisture probes. Characteristics include effect of atomic species...
Research Needs in Movement of Agricultural Chemicals to Groundwater
Better prediction of the movement of agricultural chemicals to groundwater is necessary to permit development of best management practices to reduce adverse environmental effects of agriculture....
Geochemical Factors Affecting Trace Element Mobility
Selected geochemical processes to be considered when modeling the movement of trace elements in soils are presented. The topics covered include: solid phase-solubility equilibria, ion...
Chemically-Enhanced Treatment: An Alternative to Biological Secondary Treatment for Ocean Outfalls
Chemically-enhanced treatment is a process whereby chemicals are added to wastewater in order to enhance solids removals through coagulation. This treatment process can obtain removal...
Asphalt Changes in Drum Dryer and Batch Operations
The study was designed to determine whether steam distillation of asphalt takes place in a drum dryer mixer by comparing changes induced by various laboratory conditioning (aging) techniques...
On the Road to Clean Air
Anticipating passage of the 1990 Clean Air Act in the fall of the year, this article examines the remaining air quality problems in U.S. cities and some efforts underway or being planned...
Return to search