Brazil's Vale readies tailings dams for wet season

Brazilian mining titan Vale is reinforcing its tailings dams in preparation for the rainy season, which is expected to be intense. 

"Vale's dams have their safety and stability conditions continuously evaluated by internal and external teams and competent public bodies. The results of these studies are applied to determine the dimensioning of the water drainage systems of the dams, in addition to indicating controls that can increase the safety of structures, even during rainy periods," Vale said in a statement. 

Vale is de-commissioning its tailings dams, closing five this year and 12 in total so far. Nine were closed in Minas Gerais state and three in Pará.

Tailings dam collapses caused major disasters in 2015 in Minas Gerais’ Mariana municipality, where a structure by iron ore pellet maker Samarco, a Vale-BHP JV, collapsed, and in 2019 in Brumadinho, where also a Vale dam collapsed. The disasters caused around 300 deaths and massive environmental damage, and led the federal government to force miners to decommission such structures.

Wet season starts in mid-November and ends in March. Heavy rains have already caused landslides and damaged highways, even causing some fatalities, suggesting the season will be intense.