Sustainability

Treatment of polluted soil

Thanks to its absorbing power, its buffer capacity, and its intense biotic activity, the soil is prone to self-treatment, or at least, is able to reduce the negative effects deriving from the presence of pollutants. Of course the soil self-treatment capacity has some limits. If pollution goes over this limit, the soil can lose its “filter” function in an irreversible way, provoking many damages. Differently from the atmosphere and water, which decontaminate quite rapidly, the soil, although it has a high self-treatment capacity thanks to chemical, physical, and biological mechanisms, keeps contaminated for a long period. It was noticed that, in order to significantly reduce the content of heavy metals in a polluted soil, the quantity of water corresponding to tens of years of rain is not sufficient. The presence of polluting compounds in the soil, especially highly toxic ones, can represent a risk for human health and for the environment, and requires reclamation activities. The reclamation of a land can be based on the inactivation or degrade of pollutants (they are transformed into less dangerous or not dangerous substances) or their removal by using chemical, physical or biological treatments. Reclamations is normally done on agricultural land and areas close to industrial zones or abandoned dumps.