SIMULATION OF THE RUPTURE OF AN INDUSTRIAL FERTILIZER TAILINGS DAM IN ARRAIAS, TOCANTINS, BRAZIL

Abstract

Dams are versatile structures used for various purposes, including tailings containment resulting from mining activities. In recent years, the rupture of these structures has become a recurring fact in Brazil, especially the disasters that occurred in the cities of Mariana and Brumadinho, in the State of Minas Gerais, Brazil, which caused irreversible environmental impacts and loss of hundreds of human lives. This demonstrates the relevance of computer models for predicting dam failure scenarios, which can be very useful in anticipating the consequences of dam breaks and guiding emergency action plans of dams. In the study conducted for the Itafós Arraias Mineração e Fertilizantes S.A. tailings dam was used the HEC-RAS software, which incorporates non-Newtonian fluid dam break modeling, combined with ArcGIS, ALOS PALSAR digital elevation model and other biophysical data regarding the area affected by the dam were used. Simulation of the flood wave behavior was by piping-type break, with the results indicating a flood area of 484.02 ha, maximum depth of 19.78 m, maximum wave propagation velocity of 13 m/s and maximum flow of 2,619.25 m3/s (Section 1), in addition to possible interference/impacts on natural landscapes, areas of anthropic use and public works.