6. Collection and Processing of Polluted Soil for Analysis

Risk assessment of polluted land generally involves formulation of site specific remedial strategy, which further depends on history and type of polluting activities, contaminant migration pathways and their visible impact on ecosystem. Methods of soil sample collection and their processing before analysis in the laboratory become highly important for accurate interpretation of results and devising appropriate strategy for remediation of the site. Several statistical and non-statistical methods have been used for identifying sampling locations, each of which has advantages over other. Systematic and judgmental sampling methods are preferred where contaminant migration history is known and polluted area requires more intensive sampling due to high heterogeneity. On the other hand, statistical methods avoid sampling biasness and minimize uncertainty related errors in situations. Processing and storage of samples before analysis of samples depend on the type of contaminants. This chapter also discusses on selection of appropriate instruments for soil sampling, methods of processing and storage as well as precautionary measures for minimizing errors of analysis.