Cost, time and environmental impact in the execution of mine closure coverage with geosynthetics

Abstract

Between 10 and 20 years have passed in which several countries of the South American region began declaration processes of mine closures to the respective countries in which mining companies operate. Several of these declared projects initiates actual closure processes, in dumps, tailings deposits, leaching pads, and pits. During the closure process with the use only of granular and cohesive materials; it has been observed that its extraction and placement have presented serious problems of excessive costs, lack of availability, long execution times and environmental problems due to the process of closing the borrow material areas used. This leads to observe if improvements can be made in this type of projects with the use of Geosynthetics. After more than 30 years of using geosynthetics in mining operation projects in South America, they have shown that they can be more efficient in cost and time, in addition to providing less impact benefits when used. In papers presented at other conferences on the design methodology of mine closure covers with geosynthetics, as well as methodologies for estimating the durability, they have left a precedent for their applicability and how to design them as a substitute for soils in this type of project. Experiences of coverages built following these methodologies available up to date have also been presented in congresses. This work focuses on making economic comparisons obtained by using geosynthetics in mine closure covers, as well as the time savings that can be obtained with the benefits of high quality installation using geosynthetics. The issue of impact generated by the lower consumption of fossil fuel and borrow material sites that will later require more closing work is also focused. Comparisons of these issues are presented, in order to share information to designers, project managers and environmental officials who have to deal with mine closure covers.