The New Era of Mining: Demise of Montante Dams

The collapses of the Mariana and Brumadinho dams in 2015 and 2019, respectively, marked a turning point for the Brazilian mining industry. Measures to mitigate risks, including the transformation of montante dams into alternative waste storage methods, have reflected a swift response to safety concerns. The National Mining Agency (ANM) reports that the number of montante dams has drastically decreased from 74 to just 42. This shift not only addresses immediate safety issues but also significantly impacts the economic and operational landscape for mining companies in Brazil. The decharacterization of these structures requires substantial investments; Vale, for instance, has completed 19 out of its 30 projects since 2019 at a cost of R$13.3 billion. This movement not only alters the geotechnical profile of operations but also spurs technological innovations such as filtration and dry stacking, which reduce dependency on new structures and conserve water resources. The transformation in waste management practices within Brazil's mining sector is a concrete example of companies' growing commitment to sustainability, despite regulatory challenges that still remain.