The number of riskier dams in Minas Gerais state has increased from zero to 23 after the Brumadinho disaster, which killed over 250 people at a Vale site in January this year.
Media reports said local authorities have changed parameters for attesting the “health” of an iron ore dam to fit international standards, which are stricter when compared to the Brazilian regulations.
The media report said 23 dams in Minas Gerais state, including 19 from Vale, became riskier or increased their safety risk.
Four Vale dams are at risk level 3, the highest level from 1 to 3. Level 3 dams indicate a collapse may occur at any moment.