This highlights the importance of performing site-specific investigations through numerical models, laboratory tests and field observations to better predict post-breach behaviour (ideally within a probabilistic framework) when undertaking site assessments. Although general trends may be observed in empirical observations, such efforts are prone to substantial uncertainty due to the complexity and variability of site conditions (that are typically unaccounted for in broad statistical approaches) as well as poor data availability and/or quality for many of the selected cases. Travel path confinement and steeper bed slopes enhance flow velocities (peak of 25–30 m/s) and kinetic energy, whereas flow mobility appears to be exacerbated along major rivers. The occurrence of liquefaction and/or the incorporation of free water are sufficient conditions to trigger extremely rapid, highly mobile behaviour. Weather hazards and impoundment drainage issues are identified as major causative variables. Magnitude-frequency statistics indicate that tailings dam breaches that have produced catastrophic mass flows with total outflow volumes of ≥1 M m 3 have occurred at a mean recurrence interval of 2–3 years over the period 1965–2020. The database also sheds light on the limitations of data quality and availability in the public domain. The synthesis provides insight into the influence of impoundment conditions, preconditioning and trigger variables, failure mechanisms and the downstream environment on tailings flow behaviour. This paper presents a timely review of tailings flows with the support of a comprehensive global database of 63 cases that have been remotely analyzed through a compilation of satellite imagery, digital elevation models and literature.
Tailings dam failures have received significant attention in recent years due to the catastrophic downstream consequences, as evidenced by the 2019 Feijão disaster in Brazil and numerous precedents.
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