It is estimated that pollution caused by inorganic waste and residues (minerals, inorganic matters, including metals, salts, acids, bases) resulted from industry (including mining industry) affects about 560 ha, most of areas being located in those countries where mining activities, ferrous and non-ferrous industry are well developed.
A site contaminated with inorganic waste and residues will present a risk, only if the three following elements are present:
- Pollution source,
- ways of transfer,
- the presence of populations, resources and/or protected natural spaces, likely to be reached by pollution.
The modes of exposition can be direct (ingestion of soils and dust, water ingestion, inhalation of gas coming from the soil, from the water table, or from dust) or indirect (ingestion of products for human consumption potentially polluted, like the products from the garden).
To identify the risk caused by an industrial site, a progressive procedure must be used:
- knowledge of the state of the environment, of the populations concerned and the natural resources to be protected as well as the choice of the future land uses in the case of a rehabilitation project,
- legal constraints of any nature,
- measures of control of the sources of pollution, measures of control of the impacts,
- the management of the excavated soils,
- various measures of management: rehabilitation (excavation, treatment on site or out site);
- constructive measures active or passive, measures of containment, possibilities of regeneration or natural attenuation,
- tools for the conservation of the memory and restriction of uses
- control and follow-up of the effectiveness of the management measures.
