Disclosed is a process and apparatus in which vacuum extraction is used to remove soil contaminants in both the saturated and vadose zones. One embodiment of the present invention is directed to a process for removing contaminants from a contaminated area of the ground having a vadose zone and a water table which comprises providing a borehole in the contaminated area to a depth below the water table; placing in the borehole to a depth below the water table a perforated riser pipe inside of which is situated a vacuum extraction pipe with a bottom opening situated within the perforated riser pipe said vacuum extraction pipe containing groundwater prior to application of a vacuum thereto said vacuum extraction pipe having at least one gas inlet situated below the groundwater level in the vacuum extraction pipe; while introducing a gas into the riser pipe applying a vacuum to the vacuum extraction pipe to draw gases and liquid from the soil into the perforated riser pipe and from the riser pipe into the vacuum extraction pipe and transport both the gases and the liquid to the surface as a two-phase common stream; introducing a gas into the vacuum extraction pipe at a level below the groundwater level in the vacuum extraction pipe to initiate two-phase flow within the vacuum extraction pipe; forming from the common stream a stream which is primarily liquid and a stream which is primarily gaseous; and separately treating the separated liquid and gas streams. Also disclosed is an apparatus for carrying out the process.
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