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Mining industry’s image in tatters following deadly Brazilian tailings dam collapse

TRAIL OF DESTRUCTION Wrecked mine plant and facilities at the Córrego do Feijão mine

Photo by Reuters

SWEPT AWAY The central span of the railway bridge downstream of the Córrego do Feijão mine was swept away by the force of the tailings sludge

Photo by Reuters

10th May 2019

By: Rebecca Campbell

Creamer Media Senior Deputy Editor

     

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At 13:00 local time on January 25, a deactivated tailings dam at the Córrego do Feijão (Bean Stream) iron-ore mine, owned by world-renowned Brazilian mining group Vale and located near the small town of Brumadinho, in the state of Minas Gerais, suddenly collapsed. The alarm siren did not sound. Hundreds were engulfed in the ensuing deluge. The rush of sludge – it could have travelled as fast as 120 km/h – also engulfed an unknown number of domestic and wild animals. The flood ended up covering, and destroying, the vegetation in an area of at least 269.84 ha. It also contaminated the Paraopeba river, the source of 43% of the area’s water supply.

In the immediate aftermath of the disaster, Minas Gerais state firefighters, struggling through the sludge, rescued 192 people – and 350 animals. (Animals that were still alive but trapped in the sludge and could not be rescued were shot in the head by marksmen firing from hovering helicopters.)

With rescue helicopters carrying out up to 150 flights a day in the limited airspace over the disaster area, air traffic control was provided by a rapidly deployed mobile unit of the Brazilian Air Force. As of April 20, 231 people had been confirmed dead and their bodies located, while 41 were still missing. The search for the missing then still involved 140 Minas Gerais firefighters, organised into 24 teams supported by six dogs, an unmanned aerial vehicle and 85 pieces of earthmoving equipment.

The alarm siren did not sound because it was directly below the dam and was swept away in the opening moments of the disaster. The emergency control centre personnel did not activate the emergency evacuation plan because the emergency control centre was also directly below the collapsed dam and was engulfed almost at once, claiming the lives of the people on duty there. The death toll among the mine’s employees was so high because it was lunchtime and the cafeteria was in the mine’s administrative area, which was also located below the dam. Perhaps the alarm, had it worked, would not have given the mine’s workers time to escape. But it would have given people who lived and worked downstream – beyond the mine boundaries – time to take action. With no alarm siren and no warning for them either, they too were engulfed. About half of those killed did not work on the mine.

The dam was of a type known as an upstream raised embankment dam, formed from compacted earth, and is the cheapest form of tailings dam. It was reportedly fitted with 94 pressure sensors and 41 water level sensors. Inspectors from the Brazilian operation of Germany-based global testing, inspection, certification and training company Tüv Süd had certified it as stable on September 26 last year. The report did, however, state that the base of the dam was at the limit of safety, as prescribed by Brazilian regulations. After the disaster, Tüv Süd Brasil launched its own internal inquiry to ascertain whether any of its processes and procedures were inadequate or improperly applied. Until this process had been completed, the company could not certify any tailings dams as stable. It also pledged its full support for Brazil’s “authorities and institutions”.

Meanwhile, Vale announced it was taking legal action against Tüv Süd, because it had certified the dam stable, yet it collapsed just four months later.

The disaster at Brumadinho had been preceded by another fatal tailings dam collapse at an iron-ore mine half-owned by Vale, Samarco (near the town of Mariana, also in Minas Gerais), which killed 19 people, in November 2015. (Vale’s partner in Samarco is BHP Billiton.)

Unsurprisingly, immediately after the Brumandinho collapse, urgent surveys were launched of tailings dams all over Brazil, and not only those belonging to Vale. Operations at dozens of operations were suspended by court orders or by the companies concerned (including Vale), until they could be inspected and confirmed to be safe. At the start of February, a court ordered that operations at Vale’s second-biggest iron-ore mine, Brucutu (in Minas Gerais), be halted to stop tailings from being stored at dams in the complex. The company was only able to reopen the mine in mid-April. On February 18, the Brazilian government ordered that safety and security at all tailings dams in the country be strengthened or that the tailings dams be deactivated by 2021 at the latest.

There were also international repercussions. For example, Rio Tinto launched a global review of the standards applied to its tailings dams, while Anglo American announced that it had developed a new monitoring system that would give it real-time data on strain, deformation and seepage at tailings dams. For its part, the International Council on Mining and Metals set up an independent review to establish an international standard for tailings dams.

Fallout

These disasters have effectively destroyed Vale’s reputation in Brazil, while the image of the mining industry as a whole has been severely damaged. Proposals floated by the new administration of President Jair Bolsonaro to cut regulations and speed up environmental approvals for mining were immediately scrapped. Bolsonaro overflew the disaster scene in a helicopter less than 24 hours after the disaster. He tweeted: “It is difficult to see this scene and not become emotional. We will do everything in our power to attend to the victims, minimise the damage, uncover the facts, exact justice and prevent new tragedies such as Mariana and Brumadinho for the good of Brazilians and of the environment.”

Federal Environment Minister Ricardo Salles, seen as probusiness and close to the mining industry, told Bloomberg News: “What we need at this moment is to join forces to create regulation that ensures – first of all – that best dam practices are implemented, and economic questions remain in second place.”

Multiple investigations into the disaster are now under way, including criminal investigations by the Minas Gerais State Prosecution Agency (MPMG for short, in Portuguese), the Minas Gerais State Civil Police (that is, the criminal investigation police), the Federal Prosecution Agency (whose initials in Portuguese are MPF) and the Federal Police (PF). These agencies have established a joint task force for the case. The MPF and the PF have enormous credibility, prestige and popularity in Brazil because of their role in exposing and successfully prosecuting those responsible for networks of massive high-level corruption in business and politics. As part of the criminal investigation, three Vale officials and the two Tüv Süd engineers who certified the dam as stable were placed in preventive detention. In all, 13 people under investigation were detained – twice. Other agencies are carrying out technical investigations into the dam collapse. A Parliamentary commission of inquiry has been set up by the Brazilian National Congress.

In the days that followed the disaster, investigations by the Brazilian media and officials uncovered facts that were not to Vale’s advantage. For example, it emerged that an emergency plan for the mine dated April 18, 2018, had pointed out that, if the ill-fated dam collapsed, the mine’s administrative and other areas, including the restaurant, would be destroyed.

Confronted with this information, Vale responded by saying that the plan had been based “on a study of a hypothetical rupture”. It then emerged that an unidentified Vale manager had told the MPMG, while being questioned, that the group’s executive directors had known about the decreasing level of safety at the dam. In addition, prosecutors claimed that Vale had effectively fired inspections company Tractebel (part of France’s Engie group) because, some months before the disaster, it had refused to certify the tailings dam that eventually collapsed as safe.

On February 14, the MPF submitted a formal opinion to the country’s Higher Court of Justice that Vale had prioritised profit over the safety of its workers when making decisions about the Brumadinho tailings dam. These decisions included the location of the cafeteria under the dam (or, alternatively, the failure to empty the dam). Vale contested this opinion.

At the beginning of March, the PF and the MPF advised that Vale’s then CEO, Fábio Schvartsman, and three directors – Peter Poppinga, Lucio Cavalli, and Silmar Magalhãesstep down from their positions. They did so. Ironically, when he took up the post in May 2017, Schvartsman had promised “Mariana never again”. Near the end of March, testifying before the Brazilian Senate, he claimed that he had been deceived by Vale’s own technical specialists and the external inspectors. He mentioned no names. He repeatedly stated he had never been informed that the danger at the dam had been increasing. He admitted that “something very wrong” had happened, but claimed that it was not possible to attribute the blame to Vale’s directors.

Also, by late March, Brazilian courts and government authorities had frozen Vale assets worth the equivalent of $4-billion. This was to ensure that compensation and other disaster-related costs would be paid.

In early April, the coordinator (head) of the MPF’s Brumadinho task force, José Adércio Leite Sampaio, told the Wall Street Journal that the MPF was planning to press criminal charges against Vale and a number of its officials. He stated that investigators had gathered enough evidence to show that the Córrego do Feijão management had known that the dam was ‘insecure’. What had not then been established was whether Vale’s executive management had known this. On April 16, the PF, armed with search and seizure warrants, raided Schvartsman’s home and, simultaneously, those of four other unidentified directors in four different cities in three states.

What Happened?

The most probable, but not certain, cause of the collapse of the dam was liquefaction. The whole structure of an upstream raised embankment dam, like the ill-fated dam at Córrego do Feijão, is built of mud and depends on dried mud for its stability. Liquefaction happens when solid material, under stress, acts like a liquid. With compacted earth and mud, which are under stress, the addition of even a small amount of water can cause liquefaction, resulting in the structure losing its integrity and collapsing. This can happen very rapidly. However, how the water got into the hardened mud is another question.

Edited by Martin Zhuwakinyu
Creamer Media Senior Deputy Editor

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