Evaluation of a Sustainable and Passive Approach to Treat Large, Dilute Chlorinated VOC Groundwater Plumes

APTIM Authors/Contributors

Abstract

This project aimed to demonstrate effective in situ biological treatment of large, dilute cVOC plumes using a sustainable and cost-effective approach. The critical objectives were to determine whether an off-the-grid biosparging system could sustainably and economically deliver gaseous amendments in a biobarrier configuration across a large, dilute plume, stimulating indigenous bacteria to biodegrade target cVOCs, and whether consistent in situ treatment to target levels was feasible. During the project, an oxygen and propane with ammonia cometabolic biosparging system in a barrier configuration was successfully utilized to degrade cVOCs in the plume. This cometabolic bioremediation effort demonstrated that low, yet still above MCL cVOC concentrations in large plumes can be sustainably and cost-effectively treated for cases when attenuation processes are insufficient to protect receptors. Application of the improved methods to treat contaminants may result in significant cost savings when the reduction of cVOCs in a large, dilute groundwater plume is a significant driver of remediation costs.

• Executive Summary
• Key Findings
• Final Report