Systematic Approach to In Situ Bioremediation in Groundwater Including Decision Trees on In Situ Bioremediation for Nitrates, Carbon Tetrachloride, and Perchlorate; Technical rept

摘要

Applications submitted to regulatory authorities containing in situ bioremediation have not been prepared nor evaluated using a consistent and accepted suite of parameters. The ITRC In Situ Bioremediation (ISB) Team prepared this document to provide guidance for the systematic characterization, evaluation, and appropriate design and testing of ISB for any biotreatable contaminant. It serves as guidance for regulators, consultants, responsible parties, and stakeholders when an ISB technology is considered. Bioremediation is the application of biological treatment to the cleanup of contaminants in groundwater. Bioremediation melds an understanding of microbiology, chemistry, hydrogeology, and engineering into a cohesive strategy for planned and controlled microbial degradation of specific classes of organic compounds and in certain instances, inorganic compounds. This assemblage of science and engineering requires a rigorous degree of data evaluation to determine the effect and efficiency of bioremediation. In situ bioremediation creates subsurface environmental conditions, typically through oxidation-reduction manipulation, which induce the degradation of chemicals (i.e., the target chemical) via microbial catalyzed biochemical reactions. In turn, the microbes produce enzymes that are utilized to derive energy and that are instrumental in the degradation of target chemicals. To accomplish this chain of events, the following aspects must be considered: type of microorganisms, type of contaminant, and geological conditions at the site. Since in situ conditions are manipulated by engineered means, the most important consideration is the ability to transmit and mix liquids in the subsurface.