Evaluation of environmental rehabilitation practices in bauxite mining at the plateau of poços de caldas

Abstract

Bauxite mining has been carried out around Poços de Caldas, Minas Gerais, since the 1940s. Companies operating in the region pioneered land rehabilitation in Brazil, conducted since the early 1980s. Different procedures of recontouring, runoff drainage, soil preparation and vegetation planting were employed. This research aims to evaluate current environmental rehabilitation practices employed in the region, in order to identify possible deficiencies, investigate probable causes of these deficiencies and prevent recurrence of failures, thus avoiding rework and additional costs to deliver outcomes satisfactory to land owners. Areas with different ages of rehabilitation were studied. The practices adopted in recently rehabilitated mines and in the final phase of operation were evaluated through a problem identification procedure, based on field observations, document analysis and interviews. Some unsatisfactory results were found related to ground terracing, drainage systems, block sliding, soil sampling, soil preparation, planting of vegetation and monitoring of the recovered area. Improvements are proposed, on the basis of good practices, that even if more complex and laborious, can result in future savings, as they enable, in addition to avoiding rework, the fulfillment of contractual obligations to landowners and regulatory bodies.