05271693 is referenced by 50 patents and cites 10 patents.

An Enhanced Deep Soil Vapor Extraction Process and Apparatus utilizes heaters placed into the soil at least to the depth of contamination and a vapor/condensate extraction system that withdraws volatilized contaminant vapors from the subsurface and any condensate that collects in the extraction well. Depending on the rate of formation of condensate in the well, a second conduit may be placed inside the well for the collection and removal of condensate by a downhole pump or a suction device located at ground surface. The process is directed towards contaminants trapped in or below the normal groundwater level. Groundwater extraction wells are also employed to create a "cone of depression", or local draw-down of the groundwater to expose those soils that are normally water saturated and thereby permit decontamination of such soils. Conduits may be placed within the groundwater extraction wells for the purpose of extracting groundwater.

Title
Enhanced deep soil vapor extraction process and apparatus for removing contaminants trapped in or below the water table
Application Number
7/958844
Publication Number
5271693
Application Date
October 9, 1992
Publication Date
December 21, 1993
Inventor
Arnold R Marsden Jr
Mount Vernon
WA, US
Arthur L Otermat
Houston
TX, US
Lynton W R Dicks
Houston
TX, US
David A Weingaertner
Framingham
MA, US
Paul C Johnson
Houston
TX, US
Assignee
Shell Oil Company
TX, US
IPC
E02D 3/11
B09B 3/00
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