Replicating of Brumadinho Tailings Dam Failure: Using a Two- Phase Flow Model

ABSTRACT ONLY - Recently there have been a number of tailings dam failures worldwide, thus the importance of sharing knowledge to establish methodologies for assessing and mitigating the hazard is critical. A mining disaster occurred on the 25th of January 2019 in the Brumadinho city, Minas Gerais State, Brazil. The rupture of an iron ore mine tailings dam generated a mud wave of 10 m that spread over 10 km downslope and reached the Paraopeba River inundating the mine's offices, houses, farms, hotels, and roads. The estimated volume released was 9.7'¯million'¯m³. Victims numbered in hundreds, and the economic impact was felt throughout the entire country. Video footage of the moment of the dam collapse and several technical reports provide an opportunity to replicate the tailings dam failure. The data included the dam geometry and material and the mudflow area of inundation and timing as well as anecdotal reports. This presentation focuses on replicating the tailings dam breach failure volume and subsequent downstream two-phase flow (water and mudflow) to predict the area of inundation. FLO-2D is a fully integrated dam breach and two-phase 2-D surface flood model that combines hydrology and flood hydraulics. The model simulation results are compared with mudflow depths and arrival times at key locations while accurately predicting the area of inundation. Mine tailing storage represent one of the most significant life threatening and environmental liabilities and the use of a comprehensive modeling tool is an effective method of mitigating the mudflow hazard and improving emergency planning, and evacuation.