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RESIDUAL SATURATION OF PACKED COLUMNS WITH CHLORINATED SOLVENTS

Studies were designed (i) to evaluate the effects of media and fluid properties on water and DNAPL retention in unsaturated porous media and (ii) to develop a predictive retention model. Residual saturations were measured for l,l,l-Trichloro-ethane, 1,2-Dichloroethane and Chloroform in columns packed with water-wetted glass beads. Linear correlations were demonstrated for specific retention in terms of particle size, interfacial tension, fluid densities, and Bond Number. Residual saturation of mixed glass beads, sands, and soils should be approximated by the resulting model. Experimental observations and model predictions are presented and discussed.

Key words: DNAPL, retention, saturation, porous media.