ABSTRACT
The in-situ bioremediation process also degraded the reinjected contaminants to nontoxic end products, which is an advantage over some forms of surface treatment. This chapter provides background information on the state of knowledge of chlorinated aliphatic hydrocarbons (CAHs) biodegradation. It discusses field as well as laboratory testing of the process. The chapter summarizes the potential application of biological destruction for various CAHs, and also discusses the effect of site conditions on the probability for success of in-situ field applications. The major chlorinated solvents used in the past are carbon tetrachloride, tetrachloroethene, trichloroethene. These compounds can be transformed by chemical and biological processes in soils to form a variety of other CAHs, including chloroform, methylene chloride. Methane and oxygen were added to the surface-treated reinjected water. For Methanotrophic treatment, methane and oxygen would be introduced directly into the recirculating ground water. This method would eliminate pumping the contaminated ground water to the surface, surface treatment, and subsequent reinjection.
