Brazil’s worst environmental disaster began on November 5, 2015, when the Fundão tailings dam at the Samarco iron ore mine suddenly collapsed. What followed was one of the most destructive events in modern Brazilian history. A wall of toxic mining waste surged downriver, wiping out entire communities, killing 19 people and poisoning ecosystems across hundreds of miles. Ten years later, the fight for justice has shifted across the globe and has now produced a historic ruling in a London courtroom that places responsibility on one of the largest mining companies in the world.
This new decision against BHP Group, one of the owners of Samarco, has connected thousands of Brazilian victims with the British legal system. For many families who have waited years to be heard, the ruling represents the first time a major court has formally agreed with what they have claimed since the day the dam failed.
What Happened When the Dam Collapsed
The collapse began without warning in the mining region of Minas Gerais state. The Fundão dam was designed to hold back vast quantities of tailings, the thick and sometimes toxic waste created during iron ore processing. When the structure gave way, nearly 50 million cubic meters of sludge rushed downhill.
The force was so great that houses were crushed like paper. A car was swept onto a roof. Two dogs were left stranded on top of wreckage. The entire village of Bento Rodrigues was destroyed within minutes. Bridges, roads, farmland and churches vanished under the advancing wave of mud.
A study from the University of Ulster found that enough mine waste poured out to fill 13,000 Olympic sized swimming pools and contaminate 600 kilometers of the Doce River. Fourteen tons of freshwater fish were killed. The Krenak Indigenous people, who consider the river a deity, saw their sacred waterway permanently altered. Ten years later, heavy metals still pollute the river.
Who BHP Is and How It Was (Allegedly) Responsible?
BHP Group is an Anglo Australian mining giant and one of the largest resource companies in the world. It owns fifty percent of Samarco, the operator of the iron ore mine where the dam failed. The company did not own the dam outright, but a long trail of documents and internal communications convinced victims and their lawyers that BHP played a key role in decisions that increased risks.
According to the claimants, BHP encouraged the raising of the dam so the mine could expand production. They pointed to a risk matrix shared with BHP in 2009 that predicted up to 100 deaths if the dam failed. They also cited a BHP presentation from 2012 which warned that a collapse could reach the community of Bento Rodrigues in less than ten minutes. Lawyers said there was no credible plan in place to relocate the town even though the risks were known.
Families who lost everything never accepted the idea that the tragedy was an unavoidable accident. As Gelvana Rodrigues, who lost her seven year old son Thiago, said, “The judge’s decision shows what we have been saying for the last 10 years. It was not an accident, and BHP must take responsibility for its actions.”
A London Court Blames BHP
High Court Justice Finola O Farrell ruled that BHP was liable for the disaster under Brazilian law. Her decision was detailed and firm. She wrote that the risk of collapse was foreseeable and stated, “It is inconceivable that a decision would have been taken to continue raising the height of the dam in those circumstances and the collapse could have been averted.”
The judge concluded that BHP had been negligent and lacked the care and skill necessary to prevent the failure. Even though BHP was not the sole operator, the ruling said the company was heavily involved in the operation and had influence over decisions that contributed directly to the collapse.
Victims celebrated the ruling as a major breakthrough. “We had to cross the Atlantic Ocean and go to England to finally see a mining company held to account,” said Mônica dos Santos of the Commission for Those Affected by the Fundão Dam. She called the ruling a historic moment for people who had been ignored for years.
The case in London involves more than 600,000 Brazilians, 31 communities, thousands of businesses and dozens of municipalities. Lawyers have valued the potential compensation at up to 36 billion pounds, or about 47 billion dollars. This would make it one of the largest environmental compensation cases in history.
This ruling only addresses liability. The next phase of the trial will determine how much BHP must pay.
Brazil has already reached a separate settlement worth 132 billion reais, about 23 billion dollars, with Samarco and the Brazilian mining company Vale. These payments are meant to cover human, infrastructure and environmental damage. Even so, the London judge ruled that Brazilians who accepted money under the Brazilian agreement may still pursue claims in the United Kingdom unless their waivers specifically prevent it.
BHP argued that the UK lawsuit duplicates issues already resolved in Brazil. Brandon Craig, BHP’s President of Minerals Americas, said that “240,000 claimants in the London lawsuit have already been paid compensation in Brazil.” BHP announced plans to appeal the ruling. After the decision, its shares fell more than two percent and the company said it would adjust its financial planning accordingly.
For Brazil, the ruling arrives during COP30, when the country is trying to present itself as a global leader on environmental protection. Advocacy groups say the dam collapse remains a painful reminder of past industry friendly policies that failed to protect communities and natural resources.
For victims, the judgment is a long awaited form of recognition. As one claimant said outside the court, “In Brazil, it is hopeless.” Many believe that only by going abroad could they force a multinational corporation to face meaningful consequences.
For the global mining industry, the decision sends a warning. As one reporter in Rio de Janeiro summarized, claimants believe the ruling “sets a precedent for how multinational corporations operate from now on, that they can be held liable even if their operations are in other countries.”
A Disaster That Still Has No Ending
Ten years after the dam collapsed, many communities remain unrepaired. The river is still contaminated. Some families have never returned home. Others continue to search for justice.
The London ruling does not erase the suffering that began in 2015, but it may shape the future. It confirms, in the words of Justice O Farrell, that the collapse was preventable. It recognizes that warnings were ignored. And it gives families who have waited a decade a chance at accountability that once seemed out of reach.
The next phase will determine damages, but the larger story is already clear. Brazil’s worst environmental disaster has now become one of the most important tests of global corporate responsibility, and it is far from over.
