SERDP and ESTCP have invested significant resources toward understanding and validating aerobic cometabolism for the treatment of a variety of traditional and emerging chemicals of concern in groundwater, and it has proven to be a highly effective remediation approach. However, the technology has been underutilized over the years, particularly compared to other bioremediation technologies (e.g., enhanced reductive dechlorination) because there was a lack of familiarity with the technology, leading to less utilization for full-scale remediation. The primary focus of this project was a multi-faceted technology transfer to both explain the fundamentals of cometabolism and to describe potential and current field applications of cometabolic technologies at impacted sites.

The goal of this technology transfer project was to use a number of different avenues to provide practical information and guidance concerning the application of cometabolic treatment approaches (i.e., biosparging, groundwater recirculation, bioreactors, etc.). Cometabolism is a viable, yet underutilized approach for enhancing degradation of a multitude of chemicals of concern, including many chlorinated volatile organic compounds (cVOCs), 1,4-dioxane (1,4-D), N-nitrosodimethylamine (NDMA), methyl tert-butyl ether (MTBE), ethylene dibromide (EDB), and 1,2,3-trichloropropane (TCP) among others. Moreover, unlike some growth-linked remediation approaches, cometabolic processes are applicable for dilute groundwater plumes, and can be applied to treat complex chemical mixtures (e.g., sites with 1,4-D and cVOCs). 

The goal of this project was to expand the understanding and utilization of cometabolism for remediation. The target audience was DoD Remedial Project Managers (RPMs), state and federal regulators, and environmental consultants working at DoD facilities. Rather than pursue a single avenue, the technology transfer approach included three features: (1) teaching seminars (online and onsite); (2) a video showing the design and operation of a cometabolic treatment system in the field; and (3) a comprehensive, open-access review article detailing the application of cometabolic technologies for DoD chemicals of concern.

Cometabolic treatment approaches are mature and can provide DoD RPMs with a practical solution for treating a wide range of different chemicals of concern at their groundwater sites in a cost-effective manner. This project was intended to provide DoD RPMs as well as consultants and regulators, with a practical background on the applications of cometabolism. Ideally, this knowledge assisted an increased and appropriate use of this technology at field sites for a wide variety of chemicals of concern. (Project Completion - 2024).

Hatzinger, P.B., D. Lippincott, G. Lavorgna, and M.E. Fuller. 2025. Aerobic Cometabolism Revisited for In Situ Groundwater Treatment: Organisms, Enzymes, and Remediation Design Considerations. Bioremediation Journal, 1–22. doi.org/10.1080/10889868.2025.2535596. 

Hatzinger, P.B. and J.W. Kelsey. 2023. Biodegradation of Organic Contaminants. Encyclopedia of Soils in the Environment, 1(2):547-557. doi.org/10.1016/B978-0-12-822974-3.00140-3.