Soil and Groundwater Contamination Survey and Countermeasure Technologies

Category of Tchnology	Treatment	On-site Decomposition (Bioremediation)
Media	Soil, Groundwater
Contaminants	Volatile Chlorinated Organic Compounds (TCE, PCE, etc)
	Applied (Demonstrated) Substances	Trichloroethylene
Scope	Concentration Range	10 mg/l
	Hydrogeological Conditions	Saturated	Permeable Layer
	Chemical Soil Properties
	Other Remarks
Technology Description	Classification
	Status	FUnder Demonstration Soil and Groundwater Countermeasure Test Study (Performed 1996)
	Outline of Technology	The method to degrade trichloroethylene using a microbial activity by the following two steps; 1. Injection of microbes into the contaminated soil. 2. Circulation of groundwater in the contaminated soil.
	Required Pre- and Post-treatment	Fermentation and preparation of microbes are required.
	Enhance Effectiveness through Combination
	Case History	A soil lysimeter (1.5 m x 1.5 m x 2.7 m) was filled with a sandy soil and it was contaminated with trichloroethylene (TCE, 1 mg/l).  The microbes developed by Canon was cultured to the concentration of 107 CFU/ml, and injected into the lysimeter.  The average removal of TCE in the lysimeter was 60% after 48h.  The TCE concentration was decreased to less than 0.1 mg/l where the microbes were mixed with the contaminated soil.
	Application Examples
	Limitations
	Properties of Treated Soil	Properties are Generally Retained
Schematic Flow Process
Applicability	In Situ Applicability	Possible
	Ground Structures	Applicable even if Ground Structures are Present
	Required Excavation	Construction of wells for microbes injection is required.
	Groundwater Extraction	Circulation of groundwater is required
	Required Space
	Operational Time	Several days
	Installation Time
	Maintenance and Control Requirements
	Additional Remarks
Secondary Impacts to Environment	Secondary Treatment Required?
	Effects on Living Environment
	Additives	Nutrient Salts    Air Water
	Possibility of Contaminant Spreading	Observation of groundwater flow is required due to circulation.
	Secondary By-products	Dichloroacetic acid (0.02 mg/l) was observed as a degradation product.

• 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