Vale announced this week it is carrying out three impoundment projects in Minas Gerais, Brazil, in areas downstream of the Sul Superior in Barão de Cocais, B3/B4 at Macacos in Nova Lima, and Grupo dams near the community of São Gonçalo do Bação, in Itabirito.
The construction work is expected to be complete by early 2020, and the project includes de-characterization of nine dams, amounting to R$7.1 billion ($1.78 billion), Vale said in a media release.
The impoundment structures will be able to retain tailings from dams in an extreme breach scenario. Sul Superior, B3/B4, Forquilha I and III dams are all classified at Emergency Level 3.
Forquilha II and Grupo dams are classified at Emergency Level 2 and Forquilha IV dam has the Stability Condition Statement, but its operation was shutdown to comply with a request from the Brazil’s National Mining Agency that, in February, suspended the operation of Fábrica mine, where these dams are located.
The impoundment project for the B3/B4 dams at Macacos is expected to be complete by December 2019. In Barão de Cocais, emergency work has already been completed and the constructed barriers will reduce the flooding speed in case of a breach, Vale said.
The main works will be a concrete impoundment structure located 6km downstream of the 36-meter-high and 306-meter-long dam, and will also be complete by December.
The construction projects are aimed to improve community safety, after the deadly dam burst in Brumadinho in January this year, which killed more than 300 people and caused extensive property and environmental damage in the region.