This is a User Guide developed under ESTCP project, "Cost-Effective Management of Chlorinated Solvents, 1,4-Dioxane, and Other Recalcitrant Compounds in Deep, Large, Dilute Plumes through Enhanced In Situ Aerobic Cometabolic Biodegradation".

Implementation of an in situ aerobic cometabolic biodegradation (ACB) system requires careful design and planning. The scientific knowledge, engineering principles, and implementation considerations that contribute to a successful use of in situ ACB to mitigate contaminants of concern (COC) in impacted groundwater are available in the literature. The ACB technology has been demonstrated to treat dilute COC plumes that contains either legacy chlorinated volatile compounds or emerging contaminants, such as 1,4-dioxane, n-nitrosodimethylamine, and ethylene dibromide. One type of successful ACB technologies is the groundwater recirculation-based in situ ACB technology, which uses injection-extraction well pairs to achieve groundwater recirculation and amendment distribution in situ and promote growth of ACB bacteria for COC biodegradation. 

With a vision of more aerobic cometabolic treatment being considered to tackle environmental problems related to large, dilute plumes, this spreadsheet tool has been developed to aid planning and performance evaluation of a recirculation-based ACB field test. The design component of the spreadsheet tool allows the user to use anticipated treatment performance based on site-specific laboratory microcosm and site aquifer hydraulic properties to design an injection-extraction well pair for a field test. In addition, the performance analysis component of the spreadsheet tool helps practitioners analyze performance monitoring data to determine whether the ACB treatment observed in the field test meets or exceeds the treatment expectation. By analyzing the actual treatment performance observed in a field pilot test, practitioners can more confidently assess whether the recirculation-based ACB technology is suitable to be part of the overall site remedy and will be able to refine the design to achieve more cost saving.