Bioremediation in urban pollution mitigation: Applications to solid media

Contaminated land remains both a barrier to the redevelopment of urban areas and a threat to the wider environment. This chapter concentrates on the applications of bioremediation to the clean-up of solid substrates, both as a means of allowing redevelopment and also to prevent ongoing groundwater pollution. It examines both oxidative and reductive mechanisms. In situ approaches tend to be undertaken when the contamination is at great depth, with little space available, and in some cases, where the site must be kept in use during the process. Enhanced bioremediation of soil typically involves the percolation or injection of water mixed with nutrients, saturated with dissolved oxygen, or provided with another electron acceptor. An in situ soil remediation technique which attempts, in a limited way, to mitigate against this heterogeneity, known as landfarming, has been used in the petroleum industry for many years.