Application of Exogenous Bacteria

In the second procedure, organisms with an established degradation potential for TCE were injected at the site. 

In the light of possible concern over the introduction of phenol into aquifers, mutant strains of Burkholderia (Pseudomonas) cepacia strain G4 in which toluene 2-monooxygenase is constitutive have been examined in microcosm experiments. Effective removal of TCE could be demonstrated (Krumme et al. 1993 Munakata-Marr et al. 1996), although in the first experiment serious loss in the viability of the cells occurred during the 10-week incubation. This aspect therefore presents a remaining challenge. 

Experiments have been conducted in a contaminated aquifer to examine the effect of Triton X-100 on increasing the release of TCE from sediments (Sahoo et al. 1998). The increase was rather modest (ca. 30%), and is consistent with the limited effect of surfactants in increasing the availability of PAHs, which has been discussed in Part 2 of this chapter. 

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