The microbial remediation of former gasworks sites: A review

Abstract

This review has considered the feasibility of applying current microbial treatment techniques to the remediation of former gasworks. Success would appear dependent upon the contaminants of interest being biodegradable and an effective means of implementation. Contaminants of concern at gasworks include PAH, phenols and cyanides. Laboratory and field studies suggest that these contaminants are biodegradable although little data exists with respect to mixtures in the form present at gasworks. Further research is recommended in this respect. Subsurface investigations of gasworks have revealed an extremely heterogeneous environment which suggests that current in situ remedial techniques may be unsuitable. Techniques that excavate and homogenise the contamination prior to treatment may improve the chances of successful remediation. Pilot studies appear successful but future research should emphasise a mass balance approach where the significance of non biological degradative mechanisms can be assessed. Contaminated groundwaters appear amenable to treatment in surface reactors. The success of overall remediation will however be dependent on the efficiency of the hydraulic withdrawal system used. The implementation of such a scheme should only be undertaken with a clear understanding of the limitations of this technology.

Keywords:

• Bioremediation
• manufactured gas plants
• PAH
• phenols
• cyanides