The agency's director Eduardo Leão told Reuters it will bring on the extra staff so that its checks of the dams can be done annually. It currently has 30 inspectors and, according to the report, industry critics feel oversight is lacking.

The issue has come into focus particularly since the 2019 deadly failure of Vale's Brumadinho dam.

Leão said the hiring process has started, and the combined team of 70 inspectors can "certainly" inspect all dams every single year.

"(Currently), we are obliged to make a priority schedule, meaning there are three or four years that we do not visit some dams, while there are others that we visit every six months, because they are more complex, have more risks," he said.

Brazil has about 430 tailings dams. Of those, 220 are located in the same state as Brumadinho, Minas Gerais.