BIOAUGMENTATION FOR THE IN SITU AEROBIC COMETABOLISM OF CHLORINATED SOLVENTS - Bioaugmentation for Groundwater Remediation - page 238

Figure 8.6. Results of an aquifer solids/groundwater slurry microcosm test and modeling analysis
where a butane enrichment culture (Rhodococcus sp.) was added to promote the transformation
of a mixture of 1,1-DCE, 1,1-DCA and 1,1,1-TCA (adapted from Semprini et al., 2007b ).
mixtures was observed as indicated in Figure 8.6 . Model simulations of the microcosms
indicated that the microbial populations increased from less than 1 mg/L to over 20 mg/L
over the 100 days of incubation (Semprini et al., 2007b ). The simulations of the results of the
microcosm tests (Figure 8.6 ) showed that butane inhibition of CAH transformation (especially
transformation of 1,1,1-TCA) and transformation product toxicity (especially on 1,1-DCE) were
important processes. The microcosm tests yielded trends similar to the field tests (described in
Section 8.4.3.3 ), where 1,1-DCE was observed to be rapidly transformed while 1,1,1-TCA was the
most slowly transformed and was the most inhibited by the presence of butane.
Microcosm studies of bioaugmentation with butane-utilizing bacteria for the aerobic
cometabolism of chloroform (CF) were performed by Frascari et al. ( 2007 ). Bioaugmentation