Volatile chlorinated hydrocarbons (CHC) belong to the group of organic compounds probably most frequently found in waste disposals or contaminated sites. Due to their high vapour pressure and low adsorption within mineral soils, they appear relatively easy to extract from the contaminated soil. In particular, the unsaturated zone can be decontaminated at low cost using the method of soil air extraction, this at least under favourable site conditions. However, the process of cleaning the saturated zone and the capillary fringe is considerably more difficult and time-consuming.