Numerical Investigation on Tailing Dams Stability: a Preliminary, Parametric Analysis of some Key Factors

Tailing wastes are by-products of mining industry and are generally mixtures of rock, sand, fine-grained solid material and in some cases relevant quantities of heavy metals and water remaining after the mineral values have been extracted from the patent ore. In recent years the amount of tailings has significantly increased to meet the growing demand for metals and minerals. Huge amounts of tailing wastes are produced and discharged inside storage facilities (TSF), also known as tailing dams. Owing to their complexity and high rate of collapses with relevant loss of human lives, economic and environmental damages, a detailed knowledge of the hydro-mechanical properties of tailings is essential to develop a reliable stability analysis both for new and existing structures. This research provides a preliminary parametric study aimed at investigating the impact of some fundamental design aspects. The influence of the adopted numerical method, raising techniques, distance of decant pond, hydraulic conditions, geometry of drainage systems and uncertainty of geotechnical properties on stability of an embankment have been evaluated for a simple case, providing some fundamental concepts to be considered when designing new tailing dams or performing stability analysis on existing ones.