Soil and Groundwater Contamination Survey and Countermeasure Technologies

Category of Tchnology	Treatment	Treatment
Media	Soil
Contaminants	Oil (Non Volatile Hydrocarbons)
	Applied (Demonstrated) Substances	Oil
Scope	Concentration Range
	Hydrogeological Conditions	-	-
	Chemical Soil Properties	pH 4 - 10
	Other Remarks
Technology Description	Classification	Decomposition
	Status	Under Demonstration Soil and Groundwater Countermeasure Test Study (Performed 1996)
	Outline of Technology	Contaminated soil is accumulated as a pile or contained in a container with nutrient and aeration.  Organic materials are vaporized by aeration, and decomposed by bacteria in aerobic atmosphere.
	Required Pre- and Post-treatment	Off-gas treatment is necessary.  Other method should be combined when difficult-to-decompose materials coexist.
	Enhance Effectiveness through Combination
	Case History	A soil, which had been contaminated for 20 years, was tested.  About 30% of contaminant was reduced after 84 days.  Alkane and aromatic hydrocarbon were decomposed 40 to 50%, however, asphaltene and resin were rarely decomposed.  Another examination  also indicates only 50% decomposition.
	Application Examples	Another company also applied in practice.
	Limitations	Easy-to-decompose materials may have already reduced naturally before the examination in the above mentioned case.  Temperature affect the efficiency of decomposition.
	Properties of Treated Soil	Properties are Generally Retained
Schematic Flow Process	Schematic Diagram of Medium Size Bio-pile
Applicability	In Situ Applicability	Possible
	Ground Structures	-
	Required Excavation	Excavated soil is treated (To be applied to excavated soil)
	Groundwater Extraction
	Required Space	Considerably large
	Operational Time	-
	Installation Time	-
	Maintenance and Control Requirements	-
	Additional Remarks	Need long time
Secondary Impacts to Environment	Secondary Treatment Required?	Off-gas Treatment
	Effects on Living Environment
	Additives	Nutrient Salts    Air Water
	Possibility of Contaminant Spreading	Off-gas treatment should be appropriate.
	Secondary By-products	Substance which is not decomposable by bacteria nor removed by soil vapor extraction may remain.

• 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