a system and method is disclosed for removing dissolved organic impurities , such as gasoline or other hydrocarbons , from groundwater . the contaminated water is fed into a stripper column , operated under a deep vacuum , to enable the water to enter the column at its boiling point . steam , as a vaporizing gas , strips the impurities out of the water and the overhead vapor phase is compressed to boost it to a higher pressure , so it can be condensed to vaporize part of the bottoms stream from the column . since the bottoms stream is mostly water , the vapor generated is the steam used to strip impurities from the water .