Environmental reclamation of mining areas in the portuguese sector of the Iberian Pyrite Belt: state of the art and future perspectives

Research programs on abandoned Portuguese mining sites have been developed by the INETI (ex-Instituto Geologico e Mineiro) since 1994. The analysis of the environmental impact of the Portuguese mines of the Iberian Pyrite Belt (IPB) permits their classification in a ranking. A number of criteria were followed for the assessment and hierarchization of the mine sites according to their degrees of harmfulness and hazardness. For the assessment of the parameters, emphasis was given to geological and mineralogical aspects of the ore deposits, as well as to the methodology of the ore extraction and processing, and to the dimension, composition and stability of the mining tailings. Aspects related to the land and water use and to the impacts originated in the landscape around the mining areas were also taken into account. Presently the INETI is developing detailed geological and mining mapping of the major massive sulphides mines on the Portuguese sector of the IPB. This work, also contributes to the correct understanding of the complex geochemical process developed in these areas. The mapping of the IPB mines is integrated in a mining heritage program, developed with local municipalities and environment and tourism government entities. The sustainable development of the geo-mining tourism is the main goal of these activities. Other research programs developed in the S. Domingos and Aljustrel mines, like the MINEO and e-ECORISK projects, permit a better knowledge of the impact of the old mines, based on the application of new monitoring techniques such as remote sensing and detailed multielementar analysis of soils, streams, rocks, ores and mining waters.