Chapter 2 : Suspicions to Solutions: Characterizing Contaminated Land

Abstract:

A successful approach to bioremediation involves site characterization that takes into account careful consideration of appropriate microorganisms, their survivability, and their response to various contaminants. Reliable information on the presence, type, and extent of contamination at a site is therefore vitally important. Risk assessment with respect to contaminated land serves two main purposes. First, it can be used to measure the degree of significance of contamination at a site. Second, the level of cleanup required in order to make a site suitable for its intended use may also be determined. There are four key steps in the process of assessing the risks associated with pollutant linkages: hazard (source) identification, exposure assessment, toxicity assessment, and risk characterization. The long-term leaching potential for soil contaminants and gas generation from organic materials are two common causes for remedial work in advance of development even where existing water quality and soil gas concentrations do not necessarily pose a risk until development has taken place. There are partial models to quantify the risks posed to groundwater, surface water, ecosystems, and human health. The outcome of the investigative and risk assessment processes should be a report that is readily understandable by the client, the other members of the professional team, and the appropriate regulatory authorities. A high standard of presentation is therefore important, and the report should describe the various stages of the work undertaken, together with the findings obtained and any assumptions that may have been made.