Modelling the Brumadinho tailings dam failure, the subsequent loss of life and how it could have been reduced

Abstract

<jats:p>Abstract. In recent years the number of tailings dams failures has increased. On 25 January 2019, the Brumadinho tailings dam in Brazil suddenly failed releasing a mudflow over 10 m deep comprising some 10 million m3 of mining waste which killed between 270 and 320 people. This paper details the use of an agent-based model, known as the Life Safety Model (LSM), to estimate the risk to people downstream of the Brumadinho tailings dam and to assess if the number of fatalities could have been reduced if a warning had been received prior to or at time the dam failed. The LSM modelling indicates that even if a warning had been issued as the dam failed the number of fatalities could have been reduced. Agent-based modelling tools such as the LSM can help to inform and improve emergency plans for tailings dams, which will help to reduce the risk posed by them in the future. </jats:p>

DAMSAT: An Eye in the Sky for Monitoring Tailings Dams

“…The vulnerability functions for people and buildings in the LSM were originally developed based on the characteristics of floodwater, but these can be modified to consider that tailings dam failures produce a mudflow which, unlike floodwater, is non-Newtonian in nature. The LSM was used to model the Brumadinho tailings dam failure in Brazil that occurred in January 2019 (Lumbroso et al 2020). The LSM was run for a number of scenarios and estimated that between 216 and 345 died.…”

“…The LSM allows the effects of improved warnings on loss of life and evacuation times to be assessed. Research on the Brumadinho case study found that even if a warning had been provided just as the dam failed, the number of fatalities could have been significantly reduced (Lumbroso et al 2020).…”

“…The LSM uses the water or mudflow depths and flow velocities from a two dimensional mud and flow inundation model as input. To determine the mud flow being released during the failure, a dam breach model called EMBREA-MUD has been specifically developed for tailings dams (see Petkovšek et al 2020 for more details). EMBREA-MUD is based on a predictive dam breach model developed over a number of years (see Mohamed et al 2002;Morris 2011).…”

“…Tailings outflows are represented by a separate non-Newtonian viscous layer, as well as a water layer. The tailings dam model was verified using empirical data from laboratory tests, as well as data from the Mount Polley tailings dam failure in Canada in 2015 and the Merriespruit tailings dam disaster that occurred in South Africa in 1994 (Petkovšek et al 2020).…”

A Two-Fluid Simulation of Tailings Dam Breaching

“…The model outputs include time series of water and tailings outflows, which can be used to assess potential downstream impacts, thus contributing to risk management and emergency planning. The assessment of economic damages and health impacts, including loss of life downstream of the dam, requires other 1 3 models or assessments that are not discussed further in this paper, but are included in a paper by Lumbroso et al (2020).…”