Decision makers should evaluate the selection of the remediation technologies also in relation to the effects that it may have on the soil quality. Many processes, indeed, determine significant changes in soil characteristics (e.g. pH variation, red-ox conditions, fertility, structure loosening, sterilization and decline of biological activity). Action for restoration of degraded areas, therefore, should take care of both costs for remediation and management of the site to secure, of the hazards derived from the site itself, and of the benefits derived from site restoration.
Metal contamination persistence and little knowledge of mechanisms regulating the interaction soil-metal and the sorption of contaminants by living organisms make soil remediation particularly difficult and expensive. Any of the current technologies are actually effective and applicable at wide scale. The most utilized technical solutions are clearly inadequate for cleaning large areas of moderately contaminated land, where soft and (environmental) friendly technologies are needed to restore soil fertility, in such a way that they could be utilized for agriculture or public/residential green areas. Therefore, in recent years the interest of both public Authorities and private Companies (e.g. Dupont, Monsanto) towards innovative methodologies for decontamination and restoration of contaminated sites is ever increasing.