Avaliação da Recomposição Topográfica e Revegetação de Áreas Mineradas em Candiota - RS

Abstract

Mining is an essential activity that provides raw materials for several industrial sectors, but which has direct impacts on the environment. The recovery of mined areas through topographic recomposition and revegetation is the path by which these impacts can be mitigated. Companhia Riograndense de Mineração recovers its impacted areas in parallel with mining activities, using sterile material from mining to topographically recompose previously mined areas, covering them with fertile soil and carrying out revegetation. This study estimated the time elapsed between the start of mining and the end of revegetation and evaluated the changes that occurred in the relief after mining and recovery of these areas. As characteristics, this research is classified as descriptive, applied in nature, with qualitative and quantitative approaches and uses documentary research and field research to achieve its objectives. To calculate the average time until revegetation, points were established whose coordinates served as the basis for documentary research on the dates of removal of topsoil and grasses planting. In order to assess changes in relief, field topographic surveys were conducted in two selected areas (Area-1 and Area-2) and compared with topographic surveys previously conducted in the same locations. The average time found was 6 years and 11 months between the topsoil removal and post-mining and recovery revegetation. Regarding the evaluation of relief changes, in Area-1 the topographically recomposed relief presents higher altitudes than the original relief, maintaining a similar slope and presenting terraces for the drainage of rainwater. In Area-2, the recomposed relief presents significantly lower altitudes and significant shape variation compared to the original relief.