Diane Jeantet | Associated Press | March 24, 2019
Brazilian mining giant Vale announced communities in the southeastern state of Minas Gerais have been ordered to evacuate after independent auditors found one of its dams could collapse at any moment.
On Friday, the company raised the level of risk at a mining waste dam in the city of Barao de Cocais to three, the highest grade. According to Brazil’s mining and energy secretary, level three means that “a rupture is imminent or already happening.”
Residents within a 6-mile perimeter of the dam had already been told to leave by state authorities in February after Vale raised risk levels to grade two, a company spokesperson told the Associated Press. The spokesperson, who asked not to be identified, said 442 people had been relocated to temporary housing or with family members since February.
Lt. Col. Flavio Godinho, of the state’s civil defense department, told reporters that authorities are studying the Barao de Cocais structure to review the existing contingency plan.
“Any activity at the dam could trigger a rupture,” Godinho said on Globo TV.
The news comes nearly two months after another Vale-operated dam in the nearby city of Brumadinho collapsed, unleashing a wave of toxic mud that contaminated rivers and killed about 300 people.
The contamination of rivers with mining waste, or tailings, which contain high levels of iron-ore and other metals is of great concern and can last for years or even decades, experts say.
Brazilian environmental group SOS Mata Atlantica said it had proof of water contamination in the large Sao Francisco river as a result of the Brumadinho dam collapse. Hundreds of municipalities and larger cities such as Petrolina, 870 miles from Brumadinho, get drinking water from the Sao Francisco.
Brazil’s National Water Agency, which is carrying out its own water tests, denied further contamination of the Sao Francisco river, according to Globo’s news portal G1.
The type of structure used to hold back mining waste in Brumadinho was the same as the one currently in use in Barao de Cocais, which lies about 93 miles away.