Numerical modeling for mining dam cover infiltration design with geosynthetics: A trade off study

Abstract

In the mining dam closure project, depending on the classification of the tailings, cover systems are used to reduce precipitation infiltration over time, avoiding future environmental impacts associated with metal leaching. Furthermore, reduced infiltration promotes reservoir drainage and therefore improved geotechnical stability. The covering system can be built from different materials, natural or synthetic, or even using waste itself. The main objective of this study is to present the results as a trade-off study of a one-dimensional modeling performed considering 3 configurations of geosynthetic covers, using the SOFTWARE SEEP/W emphasizing the importance and impact of the presence of geosynthetics. Since numerical models constitute an essential tool in the development of engineering projects, computational numerical modeling was carried out using Brazilian climatic parameters from the National Institute of Meteorology in conventional and automatic stations, and historical geotechnical parameters for a structure located in the state of Minas Gerais. Gerais (Brazil). For the comparison of the cover configurations, the thickness and type of the geosynthetic were varied. The results emphasize the importance of studying numerical modeling in the pre-closure design phase, to define a viable, economical and sustainable coverage, and contribute to the use of geosynthetics in this type of application.