11 - Bioremediation of soil

Abstract

The chapter discusses up-to-date methods in the microbial decontamination of soils and deals with many aspects of bioremediation including security, microbiological and chemical analysis, in situ and ex situ techniques, as well as the reuse of soils after decontamination. Together with the level of danger present in any construction venture, working in contaminated areas involves an additional risk potential due to contaminants. The in situ remediation results in a lower number of safety measures than on-site and off-site remediation, because there is less chance of coming into contact with the contaminated materials. On-/off-site remediations are equal with regard to the amount of safety technology required. The use of the fundamental precondition for the determination of safety is the careful examination of the site and the determination of the danger level to the customer before any work is started. Appreciable accidental danger is mainly caused by the accompanying work, such as handling the contaminated material that is to be remediated or reclaimed. Besides chemical, geological, and hydrological studies of the risk potential of contaminated sites, the estimation of microbial activity and the quantification of microbial populations supports information on the physiological state of soil microflora or whether microorganisms do exist in the contaminated soil. It is necessary to carry out detailed studies on the influence of different parameters on the degradation rate of xenobiotics present in a contaminated soil matrix, prior to any large-scale bioremediation procedure. The treatment of contaminated soil can be performed routinely by applying several different technologies that are currently available.