by Jennifer Jensen, Associate Editor

Engineering and Mining Journal offers its prayers and condolences to our friends and colleagues at Vale and all those who have suffered a loss during this tragedy.

On the afternoon of January 25, a tailings dam collapsed at Vale’s Feijão mine in Brumadinho, Minas Gerais, killing at least 99 people and leaving more than 250 missing when part of its contents reached the company’s administrative area and part of the Vila Ferteco community.

The dam contained 11.7 million cubic meters of tailings, but was inactive, according to Vale. Plant facilities, the loading terminal, the maintenance workshops and the administrative buildings of the Córrego de Feijão mine were damaged.

Vale is currently investigating how and why the dam failed.

The dam was most recently inspected in September and had a safety factor “in accordance with the world best practices” and was “above the Brazilian Standard,” according to Vale. The dam also went through biweekly field inspections, the company said. The last one reported to ANM (National Mining Agency) occurred on December 21.

There was fear another burst might happen on January 27, around 5:30 p.m., in the region of Córrego do Feijão mine in Brumadinho after the company detected an increase in water levels. The community in the region evacuated to safe designated places, but were able to return after Vale reduced the amount of water in the reservoir and it receded to safe levels.

Shortly after the failure, the company established two independent consulting committees. The first independent committee will be dedicated to follow up on the measures taken to support the victims and the recovery of the areas affected by the breach of the dam. The second independent committee will be dedicated to investigating the causes and responsibilities for the dam breach.

Vale now faces legal and criminal actions.

As of January 30, the Minas Gerais Court had blocked R$11.8 billion ($3.2 billion) to guarantee the recovery of damages caused by the dam breach. In addition, sanctions by IBAMA and the state of Minas Gerais amounted to approximately R$350 million ($95.8 million), according to Vale.

A preliminary injunction was granted after the Public Ministry of Labor filed a civil action, freezing R$1.6 billion ($437.5 million) to secure compensation for direct and third-party employees that worked in the Córrego de Feijão mine at the time of the dam breach; maintenance of the wage payments to the relatives of direct and third-party employees that are still missing while the status of fatality is unconfirmed; payment of funeral expenses, transfer of body, burial of all direct and third-party employees; and other administrative measures.

Also, on Janaury 28, a class action complaint was filed against Vale, its CEO Fabio Schvartsman, and CFO Luciano Siani Pires in the United States District Court for the Eastern District of New York. The complaint alleged the company made false and misleading statements, and omitted to make disclosures, concerning the risks and potential damage of a dam breach, violating the Securities Exchange Act of 1934.

“The proceeding is still in early stage, Vale intends to defend vigorously against the claims,” the company said in a statement.

Several people have also been arrested in connection with the dam failure. On Tuesday, January 29, three employees of Vale and two contractors were arrested. Two of those arrested were Vale’s senior managers at the Corrego do Feijao mine.

Vale said it is fully cooperating with the authorities.

“The company will continue to contribute to the investigations to find out the facts, along with the unconditional support to the affected families,” the company released in a statement. “Three employees of Vale were detained together with two people responsible for the audit company that testified to the stability of Dam I.”

On January 30, Vale submitted a plan to contain the tailings leaked from the dam. Dikes will be built in the Brumadinho mine area to contain sediments from the tailings. The installation of a barrier for sediment retention near the water catchment of the city of Pará de Minas and the construction of a sediment containment barrier in the Paraopeba river concluded on January 31, the company said.

Vale will also decommission all its dams built by the upstream method. In 2015, Vale had 19 upstream dams in operation, but made them inactive, initiating the decommissioning process. However, there are still 10 active upstream dams. The structures will undergo a de-characterization process and operations will be temporarily halted. It should take up to three years with an investment of R$5 billion to decommission the dams, according to Vale.
 
Schvartsman said production would be reduced by 10% to decommission the dams. Vale estimated that the reduction would amount to a loss of 5 billion reais (US$ 1.3 billion) in the next three years.

This is the second dam failure by a company owned by Vale. The first occurred in 2015 at Samarco, also in Minas Gerais, owned by Vale and BHP. That disaster killed 19 and devastated the local community.