Soil and Groundwater Contamination Survey and Countermeasure Technologies

Category of Tchnology	Treatment	Emission Control
Media	Soil Gas, Others (Off-gas from the Stripper)
Contaminants	Volatile Chlorinated Organic Compounds (TCE, PCE, etc) Volatile Hydrocarbon (Benzene, etc)
	Applied (Demonstrated) Substances	Volatile Chlorinated Organic Compounds (TCE, PCE) Hydrocarbons
Scope	Concentration Range	The removal ratio will be getting better as the concentration will be getting higher.
	Hydrogeological Conditions	-	-
	Chemical Soil Properties
	Other Remarks
Technology Description	Classification	Separation
	Status	Fully Commercialized Soil and Groundwater Countermeasure Test Study (Performed 1995)
	Outline of Technology	The soil vapor is extracted from contaminated soil on vadose zone.  The soil vapor is led to fabric activated carbon (FAC) adsorption column to remove VOCs.  After finished adsorption process, steam is induced to desorb VOCs that adsorbed to FAC.
	Required Pre- and Post-treatment	It is necessary that the treatment of desorbed solvent and water solution.
	Enhance Effectiveness through Combination
	Case History	The bench test was performed in the dry cleaning factory.  The inlet concentration of tetrachloroethene (PCE) was over 30 ppmv.  Through the 27.7 hours operations, 5.13 kg of PCE was removed, and through the 500 hours operation 20 kg of PCE was removed.  In this case, as the factory had used hydrocarbon solvents, they were removed simultaneously.  Consequently, the break through point of FAC is influenced by quantity of total adsorbed materials (PCE and hydrocarbons)
	Application Examples
	Limitations	If it is permitted to utilize the existing facilities (steam and cooling water) cost of remediation will be reduced.
	Properties of Treated Soil	-
Schematic Flow Process	Flow Diagram of Soil Vapor Extraction and Treatment System Using Fabric Activated Carbon
Applicability	In Situ Applicability	Possible
	Ground Structures	-
	Required Excavation
	Groundwater Extraction	None
	Required Space	1.5m x 0.9m of floor space is necessary to install this system.
	Operational Time
	Installation Time
	Maintenance and Control Requirements	The treatment of desorbed liquid (solvent, water solution), monitoring of concentration of exhaust gas, periodical inspection of system.
	Additional Remarks	If the influent gas includes plural contaminants, it is needed to note the circumstances of contamination.
Secondary Impacts to Environment	Secondary Treatment Required?	Waste Treatment (Regeneration condensate)
	Effects on Living Environment	Noise
	Additives	Air Water (Regeneration waste water)
	Possibility of Contaminant Spreading	None
	Secondary By-products	None

• Understanding the Contamination Survey and Countermeasure Technology Description Sheet
• Where to make contact

Soil Environment Management Division, Water Environment Department, Environmental Management Bureau, Ministry of Environment
Tel: +81-3-5521-8319
E-mail: MOE@env.go.jp