الفهرس 
Schematic representation of an interface and the acting forcesOnly 14 pages are availabe for public view
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Abstract
A multiphase flow and transport numerical model is developed to study the leakage of light non-aqueous phase liquids (LNAPL) into the vadose zone and the associated contamination of both the unsaturated and saturated zones. The model is used to provide a better characterization tool for addressing the movement and spreading of the NAPL phase and the resulting contamination in both the vadose zone and the saturated zone. Also, the effect of heterogeneities of porous media on LNAPL leakage and the influence on the dissolved and volatilized contaminants are investigated. The heterogeneity model accounts for spatially varying conductivity, porosity, and van Genuchten parameters. It is found that the NAPL density and the capillary pressure parameters (van Genuchten parameters) increase the NAPL spreading in one direction at the expense of the spreading in the other direction. The remaining soil, flow, and transport parameters affect the vertical and lateral spreading in a similar manner. Similarly, the water residual saturation, the capillary pressure parameters, the mass transfer rate between the water phase and the air phase and the Henry coefficient have opposing effects on the total mass of dissolved and volatilized contaminants (i.e., if dissolved mass increases the volatilized mass decreases and vice versa). The remaining parameters have similar effects on the dissolved mass and volatilized mass. For the Monte Carlo simulations, it is found from results that the heterogeneity of intrinsic permeability has the major influence on the patterns of dissolved and volatilized contaminants and the amount of mass transfer from LNAPL to the water and air phases. Heterogeneity in other parameters has minor effects on the LNAPL movement and associated contaminant plumes.