Brazilian miner and iron ore producer Vale increased late this week the safety risk level of three iron ore dams to level 3, which demanded the company sound a siren as the risk of a collapse became more likely.
Earlier this week, Vale had already reported the increased risk of a collapse at its Barragem Sul Superior dam, located at its Gongo Soco mine. With the latest dam announcement, Vale increased to four the number of dams that may collapse.
Vale said the dams at risk include the B3/B4 dam at its Mar Azul mine, in the city of Nova Lima, in Minas Gerais state, as well as the Forquilha I and Forquilha III dams, both located at its Fábrica mine in the city of Ouro Preto, also in Minas Gerais state. Vale said all residents near those dams had already been evacuated as of February 16, and all three are inactive upstream dams, which are part of a decommissioning plan.
Vale said independent auditors refused to label the three dams as stable, following tougher Brazilian mining regulations after the Brumadinho disaster, which killed at least 216 people.