Example Treatability Study:

The purpose of this bioremediation Treatability Study was to verify aerobic, cometabolic mineralization of trichloroethylene (TCE) using a proprietary bacterial culture owned by a third party. With radiotracer techniques using a ¹⁴C-labeled version of the organic chemical in question (TCE), complete biological mineralization to ¹⁴C-CO₂ can be documented. The experimental system employed in this study was a radiological assay which measures the mineralization of ¹⁴C-labeled TCE to ¹⁴C-labeled CO₂. All treatments were performed in triplicate, and the experiment was replicated. Treatment groups included:

1. Bacterial culture “Treatment A”-amended site water
2. Bacterial culture “Treatment A”-amended site water- sterilized (killed control)
3. Unamended site groundwater
4. BRT positive control (phenol culture)
5. BRT positive control (phenol culture)- sterilized (killed control)

A phenol treatment was included as a positive control because phenol is a well-known cometabolite used for aerobic TCE degradation (1,2,3). Negative control treatments included corresponding autoclaved killed bacterial cultures as well as unamended site groundwater.
It is clear that our experimental system was unable to detect any aerobic, cometabolic mineralization of ¹⁴C-TCE by the proprietary bacterial culture “Treatment A” above that of the killed controls or unamended site water. The BRT positive control phenol culture exhibited 13% mineralization over the experimental time frame examined.

1. Folsom, B. R., and P. J. Chapman. 1991. Performance characterization of a model bioreactor for biodegradation of TCE by Pseudomonas cepacia G4. Appl. Environ. Microbiol. 57:1602-1608.
2. Jenal-Warner, U., and P. L. McCarty. 1997. Development and evaluation of semicontinuous slurry microcosms to simulate in situ degradation of TCE in a contaminated aquifer. Environ. Sci. Technol. 31:2915-2922.
3. Segar Jr., R. L., S. L. DeWys, and G. E. Speitel, Jr. 1995. Sustained TCE cometabolism by phenol-degrading bacteria in sequencing biofilm reactors. Water Environ. Res. 67:764-774.