Protocol for in situ bioremediation of TCE-contaminated groundwater using green remediation
Chlorinated solvents are commonly used for degreasing of electronic parts and drying cleaning industries. When they are released into the subsurface, they tend to adsorb onto the soils and cause the appearance of DNAPL (dense-non-aqueous phase liquid) pool. Among those halogenated organic compounds, trichloroethylene (TCE), a human carcinogen, is one of the commonly observed contaminants in groundwater. TCE will become hazardous to human health through drinking water exposure routes. In this study, TCE was used as the target compound, and green remediation technology was developed to remediate DNAPL polluted groundwater. The objective of this study was to develop the emulsified hydrogen releasing substrate and apply it in the permeable reactive barrier for TCE-contaminated groundwater cleanup. Results will be used for future practical application. In this study, the developed emulsified hydrogen releasing substrate contained soy bean oil , lactate , biodegradable surfactant (Simple Green: 5 w/w% and lecithin 20 w/w%), and nutrients (amino acids, trace elements, and vitamin). The emulsified hydrogen releasing substrate is able to provide carbon and hydrogen for bacterial growth. In the injection well A, the TCE concentration dropped to below 0.01 mg/L. Degradation byproducts for cis-1,2-dichloroethene and vinyl chloride. Results reveal anaerobic dechlorination is feasible and applicable technologies to clean up TCE contaminated aquifers. Thus, the in situ bioremediation technology has the potential to be developed into an environmentally, economically and naturally acceptable remediation technology. Knowledge obtained from this study will aid in designing a hydrogen-released substrate biobarrier system for site remediation.
slow hidrogen releasing material;permeable reactive barriers;contaminated groundwater;trichloroethene