Effects of Heterogeneity on Actinide Diffusion Rates in Tuffaceous Rock
The pore structure and mineralogy of Topopah Spring Tuff are heterogeneous on scales less than one cm. This heterogeneity creates spatial variation in transport rates for aqueous actinide...

Effect of Material Heterogeneities on Flow Through Porous Media
Modeling studies were conducted to determine the effects of material heterogeneities on the flow of water through rock. Multiple numerical calculations were made using random variations...

Analysis of Solute Transport in an Intermediate-Scale Unsaturated Flow Experiment
A simplified stochastic model was derived and applied to two unsaturated flow experiments conducted in an intermediate-scale caisson. Parameters for the flow and transport models were...

Theory of Matrix and Fracture Flow Regimes in Unsaturated, Fractured Porous Media
The flow behavior of a two-dimensional, unsaturated fracture-matrix system is characterized by a critical flux qf*...

Apparent and Simple Diffusion Coefficients in Compacted Bentonite
Diffusion coefficients were experimentally determined in bentonite to evaluate the effectiveness of bentonite layers as a diffusion barrier to ionic transport away from high-level radioactive...

Pilot Drywell Study Pierce County, Washington
Subsurface disposal of stormwater runoff is widely utilized in areas with permeable or porous soils, including the Clover/Chambers Creek (CCC) Basin in central Pierce County, Washington....

A Theory of Porous Plasticity at Low Triaxiality
A simple multiaxial theory of plasticity which is capable of taking into account the influence of pore shape at low concentration is developed for an isotropic porous material at a triaxiality...

Dynamic Effect of Sediment on Dam Hydrodynamics
The dam-reservoir-foundation interaction problem has been studied by many investigators. A two dimensional model of compressible porous media is employed to analyze the dynamic response...

Moisture Diffusion in Concrete and Mechanisms of Drying Creep
The Pickett effect is the excess of creep at drying over the sum of shrinkage and basic creep. Several theoretical models have been presented to speculate on the mechanisms of this effect,...

Deformation of Concrete Due to Drying
The deformation of drying concrete is numerically investigated considering the effect of random arrangement of coarse aggregates. The result indicates that a part of the statistical variation...

Water Quality Sampling Under Preferential Flow Conditions
Shallow wells, porous cup samplers, and wick and gravity pan lysimeters were used to observe the movement of bromide applied to the surface of a grass covered field during a 23 day period....

Visualization Studies of Dense Leachate Plumes in Porous Media
In this paper, a series of flow visualization experiments investigating the behavior of dense leachate plumes are described. These experiments were performed in various flow containers...

Innovative Reregulation Weirs for Dam Releases
Two different reregulation weir designs for dam release improvement are discussed. A porous timber crib is favored for applications where increased minimum flow is needed, and a labyrinth...

Oxygen Transfer in Full Lift Hypolimnetic Aeration Systems
A series of experiments were conducted to examine the effect of diffuser depth, diffuser orifice diameter and separator box surface area on oxygen transfer (mg/L), daily oxygen load (kg...

Near-Field Transport of Radioactive Chains
Much attention has been given to predicting the near-field mass transfer of a single radioactive species from a waste solid into surrounding porous material, but only limited consideration...

Simulation of Radionuclide Retardation at Yucca Mountain Using a Stochastic Mineralogical/Geochemical Model
This paper presents preliminary transport calculations for radionuclide movement at Yucca Mountain using preliminary data for retardation parameter distributions based on mineral distributions....

Diffusion Coefficients and Hydraulic Conductivity in Unsaturated Hanford Soils and Sediments
Two groundwater transport parameters of some Hanford formation materials, the hydraulic conductivity and the diffusion coefficient, were measured to aid in predicting contaminant migration....

Hydrologic Characterization of Faults and Other Potentially Conductive Geologic Features in the Unsaturated Zone
The capability of characterizing near-vertical faults and other potentially highly conductive geologic features in the vicinity of a high-level-waste repository is of great importance...

Non-Point Source Contamination of Aquifers
The paper discusses a new method for simulating the movement of contaminants from a diffuse source at the soil surface through a variably-saturated porous medium. The method accounts for...

Volatilization in Porous Media During Infiltration

 

 

 

 

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