SOIL BIOENGINEERING STRUCTURAL MODELS FOR THE REVEGETATION OF WASTE DUMPS IN OPENCAST MINING

Abstract

The technological processes associated to mineral extraction are among the main forms of environmental degradation, with an intense effect on the landscape, which may lead to several environmental damages. Among these different processes and by-products generated, the waste dump is characterized as a new environment formed by the mineral operation, with difficult vegetation recovery due to the deficiency of organic matter and nutrients, along with the granulometric heterogeneity of the material. This paper discusses the applicability of soil bioengineering techniques in recovering the slope of the waste dump from an opencast mining. Three structural models of soil bioengineering were developed, constructed and installed on the slope to recover the degraded area: guirlanda, colmeia and retentor. The indexes developed to assess the performance of the models indicate that guirlanda presented the best results, due to the low difficulty in both processes of installing the model on the waste dump and of filling the model with soil-substrate/seeds, besides the high development of green manure species in the model. The second best performance was achieved by the retentor model, and the worst one, by the colmeia model.