Water movement in soils is a key process that aff ects water quantity and quality in the environment. Movement of contaminants in soils is closely linked with the soil water fl ux and it is very important to properly evaluate these processes that occur in vadose zone. With development of new technologies more attention is dedicated to the use of numerical models to assess water fl ow behavior a...

The accidental overfilling of waste liquid from tank BX-102 at the Hanford Site in 1951 put about 10 t of U(VI) into the vadose zone. In order to understand the dominant geochemical reactions and transport processes that occurred during the initial infiltration and to help understand current spatial distribution, we simulated the waste liquid spilling event in laboratory sediment columns using ...

[1] The unsteady state drainage of water from a vertical sand column with and without a finer layer on the top was studied theoretically and experimentally to investigate the airflow generated by the finer layer. The sand column, saturated at its lower portion and initially in the condition of hydrostatic equilibrium, is drained at its bottom at constant head. The results show that significant ...

Chlorinated hydrocarbons (CHCs) are one of the pollutant groups most commonly found in hazardous waste sites. Understanding the transport and fate of these compounds in the vadose zone is crucial to identifying pollution sources, assessing the threat to groundwater, and evaluating the need and adequacy of cleanup. CHCs exist in various physical phases in the subsurface, linked by interphasal pr...

The occurrence of halogenated volatile organic compounds (HVOCs) in groundwater beneath several municipal solid waste landfills in Tucson, Arizona in the absence of significant liquid phase movement has suggested that vapor phase transport may be the principal process transporting HVOCs from the vadose zone into the water table. The results of mathematical modeling of these transport processes ...

in this paper, a modeling tool for risk assessment analysis of the movement of hydrocarbon contaminants in the vadose zone and mass flux of contamination release into the groundwater table was developed. also, advection-diffusion-reaction equations in combination with a three-phase equilibrium state between trapped air, soil humidity, and solid particles of unsaturated soil matrix were numerica...

RESEARCH OBJECTIVE The objective of this study is to to characterize and analyze in-situ flow and transport within the vadose zone during a mid-scale hydrologic infiltration experiment. This project has employed numerical and experimental tools developed under a previously funded EMSP proposal (project number 55332) to provide 3-D unsaturated hydrologic property distributions. In the present pr...