Exploration of contaminated soils and sediments

The scale and shape of areas and volumes of contamination at and below the Earthʹs surface are summarized. It is argued that in terms of their anomalous chemical composition, spatial distribution and relation with the host matrix, analogies can be drawn between bodies of contamination and deposits of metalliferous minerals. It is recommended that bodies of contamination are explored in much the same ways as mineral deposits. Additional attention must be given to their greater chemical complexity and degree of mobility. Characterization of clays and other sorbents is particularly important in contaminated soils and sediments. The scavenging property of clays means that they act as natural immobilizers of contaminants and can be employed as contaminant containment barriers. Clays are, however, vulnerable to alteration and degradation of their sorption capacity, which can lead to the release of absorbed contaminants.