12 August, 2020

Exclusive: Brazil miner Vale knew deadly dam had heightened probability collapse

BELO HORIZONTE, Brazil (Reuters) – Vale SA, the world’s largest iron ore miner, knew not too long ago that the dam in Brazil that collapsed in January and killed not less than 165 people experienced a heightened likelihood of rupturing, in keeping with an internal document seen by Reuters on Monday.

The report, dated Oct. 3, 2019 , classified the dam at Brumadinho during the state of Minas Gerais being two times certainly going to fail as opposed to the maximum level of risk tolerated under internal guidelines.

The previously unreported document could be the first evidence that Vale itself was thinking about the safety of your dam. It raises questions factors an independent audit about the same time guaranteed the dam’s stability and why the miner didn’t take precautions, that include moving a small business canteen that was just downhill with the structure.

Vale announced the report, called “Geotechnical Risk Management Results,” comprised the views of specialist engineers, who’re obliged to focus within strict procedures should they identify any risks.

“There’s really no known report, audit or study with any mention of an imminent opportunity of collapse at Dam One inch the Crrego do Feij?o mine in Brumadinho,” Vale said inside an emailed statement.

“On the contrary, the dam had it’s certificates of safety and stability attested to by local and foreign specialists.”

U.S.-listed shares of Vale extended losses on Monday following your Reuters story, dropping perhaps up to 2.6 % to $11.10. This company has lost 3 months of its market capitalization – or nearly $19 billion – because the Jan. 25 dam collapse, Brazil’s most deadly mining accident.

The disaster inside mineral-rich state of Minas Gerais was the actual major collapse of an mining dam along the coast in about couple of years, following a similar disaster in 2019 from a nearby mine co-owned by Vale.


Vale’s internal October report placed the Brumadinho dam within a “attention zone,” praoclaiming that “all prevention and mitigation controls” must be applied.

A failure cost the company $1.5 billion together the potential to kill greater than a hundred people, the report said. The dam was marked for decommissioning.

Nine other dams in Brazil, outside 57 that have been studied, were also placed into the “attention zone,” based on the report.

A separate Vale report dated Nov. 15, 2019, also seen by Reuters, states that any structure with a annual prospects for failure above 1 in 10,000 should really be brought to a persons vision of the ceo and the board.

The dam’s annual possibility of collapse was registered as 1 in 5,000, or twice the tolerable “maximum level of individual risk,” based on the report.

“That’s useless in my book, set you back consider that these are generally meant to be long-term structures,” said David Chambers, a geophysicist in the center for Science in public places Participation along with a specialist in tailings dams.

The miner said in the emailed statement that “the development of an alert of the best management, suggested in November 2019, was studied damaging credit the integration of geotechnical risk and business risks for Vale.”

Asked what came of your discussion, Vale said an alert had not been implemented.


Vale said the sources of the rupture remained being investigated. It’s got repeatedly said the collapsed dam was declared sound by an impartial auditor in September.

The audit by Germany-based TV SD, that’s seen by Reuters, said the dam honored the minimum law for stability however raised various concerns, particularly in regards to the dam’s drainage and monitoring systems.

The auditor made 17 recommendations to boost the dam’s safety.

Vale said counsel were routine and this the company dealt with them all.

The October internal report identified static liquefaction and internal erosion since the most likely reasons behind a potential failure within the dam in Brumadinho.

It continues not known what was behind the collapse, but situations environmental official told Reuters this month that most of evidence pointed to liquefaction.

Liquefaction is a process whereby a thorough material for example sand loses strength and stiffness and behaves much more like a liquid. It had been the cause of the 2019 dam collapse nearby, which led to Brazil’s worst-ever environmental disaster.

“We used to say this type of mining incidents were acts of God, however right now … we consider them failures in engineering,” said Dermot Ross-Brown, a mining industry engineer who teaches around the Colorado School of Mines.

Vale says it will invest some $400 million from 2020 to relieve its attachment to tailings dams, which store muddy detritus from mining.