Remediation of inorganics and organics in industrial and urban contaminated soils

As land previously occupied by industry comes under pressure for redevelopment, it becomes evident that a large number of these sites are contaminated. Such contamination is a concern if it has the potential to become a health hazard to site occupiers or a threat to overall environmental quality. Soil remediation is a young technology whose ultimate success will be dependent upon a combination of chemical, physical and biological knowledge. This knowledge must be built on a sound understanding of the basic science behind the mobility, reactivity and toxicity of pollutants in natural ecosystems. However, the economics of remediation and the end-use of the treated land will be major factors in the widespread adoption of clean-up technologies. Possibly the greatest single stimulus for soil remediation will be legislative pressures that define the limits of various contaminants in soil, water and the atmosphere. These standards are likely to become increasingly stringent as analytical techniques improve. Whilst there may be little justification for these levels from toxicological data, the overriding consideration will be to reduce inorganic and organic contaminant levels to ‘below detectable limits’. The implementation and policing of these regulations will be a political as well as a scientific issue and special pleading, focused on using the best available technology, risk assessment and economics, will be a common feature of the debate.