Abstract

The separation of a chlorine-based contaminant from a surface of a substrate covered with same is effected by dissolving the contaminant in a first solvent to form a solution thereof and admixing a further solution consisting of a membrane-like material forming component derived from mineral crude oil, bitumen or amphipathic lipids in a second solvent selected from the group consisting of halogenated hydrocarbons and p-xylene, the second solvent being miscible with the first solvent and capable of forming in the presence of water and the membrane-like material forming component an interfacial membrane-like material which has a water side and is impermeable to the contaminant. Water is then intimately contacted with the surface of the substrate so as to cause the membrane-like material to form at the surface of the substrate with the water side oriented toward the surface while the water wets the surface and spreads thereover, the membrane-like material incorporating during its formation the contaminant and mixture of solvents adjacent the surface, and the water displacing the membrane-like material away from the surface as it is being formed thereacross to thereby separate the contaminant and mixture of solvents from the surface and cover the surface with a layer of water. The invention is particularly useful for the decontamination of dioxin contaminated soils.