Simulação da propagação de onda de cheia decorrente do rompimento de uma barragem de rejeitos industriais de fertilizantes em Arraias, Tocantins

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 in Mariana (2015) and Brumadinho (2019), 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 in Tocantins, the HEC-RAS version 6.1 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-1 and maximum flow of 2,619.25 m3 s-1 (Section 1), in addition to possible interference/impacts on natural landscapes, areas of anthropic use and public works.