This blog is a collaboration between LMN and cosmopolíticas in Brazil.
On 5 November 2015, the catastrophic failure of the Fundão dam operated by Samarco Mineração S.A. – a joint venture between BHP owning 50% and Vale S.A. 50% – unleashed around 45 million cubic metres of tailings into the Rio Doce basin. The disaster wiped out the village of Bento Rodrigues and nearby communities, claiming 19 lives (20 including the unborn child of a pregnant woman) and affecting over 1 million residents along the river basin. The toxic flood contaminated over 600 km of waterways, eventually reaching the Atlantic Ocean. According to the Getulio Vargas Foundation’s Rio Doce project, toxic metals such as arsenic, mercury, and manganese persist in the sediments, posing ongoing risks to aquatic life and to the human populations that depend on the river. This toxic waste impacted over 40,000 hectares of vegetation, including 1,469 hectares of native forest along 77 km of waterways and contaminated the territories of several Indigenous and traditional communities, such as the Pataxó, Guarani, Tupiniquim, Krenak and Quilombolas peoples.
Negligence in the management of mining waste
This remains the worst environmental disaster caused by mining in Brazil’s history. Nevertheless, the Fundão tailing dam failure fits into a pattern. Globally, the mining industry has far too many examples of tailings dams, waste ponds, and other toxic waste where oversight has failed. Here in the UK, what has been called the worst ever mining-related disaster took place in Wales. In 1966, a coal-waste tip owned by the National Coal Board collapsed onto the mining village of Aberfan, burying the Pantglas primary school, killing 116 children and 28 adults, and devastating life in the village forever.
In 2023, LMN and representatives of the Brazilian Movement of People Affected by Dams (MAB) visited Jeff Edwards, a survivor of the Aberfan disaster. He shared his terrifying experience of feeling the avalanche of coal waste falling on his school, while his entire class was trapped with no way out, surrounded by heavy debris that prevented them from moving. He told us about the anguish he felt when he heard his classmates screaming, but also how terrifying it was to hear the silence when there was no more air to breathe. Mr Edwards explained that the trauma is not only personal, but the pain of a community losing an entire generation of children in the blink of an eye. These memories as a 10-year-old, shared in his older age, will remain until his death, said Mr Edwards. His physical injuries may have passed, but the consequences of the catastrophe remain for his mental health and the Aberfan community.
The testimonies of people in Brazil are very similar: first, the impact of the tailings dam failure; and second, the endless consequences the disaster has brought to the livelihoods, tranquillity, and mental and physical health of those living there. You can watch some testimonies shared by the Rio Doce project here.
Jeff Edwards with Leticia Oliveira and Paula Goes from MAB and Diana Salazar from LMN. Photo credit: Rebeca Binda
In Aberfan, residents had voiced concerns about the risks posed by the coal-waste tips – a cheap method of waste disposal that required little investment and no monitoring or assessment. But only after the disaster and a public inquiry was the National Coal Board found to be culpable of negligence, showing that such ‘accidents’ are in fact preventable failures of the mining industry. It then took two years of organised struggle for the British government to act, and the waste tips from the upper part of Aberfan were finally removed 5 years after the disaster.
In the Brazilian case, the communities also raised concerns about the risks posed by the Fundão tailings dam, and there have been complaints of negligence to both the government and the company. But no one has yet been found culpable of negligence in this case. On the contrary, the Samarco mine continues to operate today, generating profit and this year exiting the state of bankruptcy it claimed after 2015.
Legal battles & the lack of justice
From the very start, affected communities and advocacy organisations in Brazil have insisted that justice in Mariana and for everyone affected involves not just compensation, but full accountability, a transparent process, and systemic change. The legal dimension is central to the narrative of a lack of justice which pervades public sentiment.
Affected people have pursued justice in both Brazilian and international courts. In Brazil, compensation agreements have been put into place; however, many affected communities argue that the agreements so far still exclude large numbers of people, that payments have been scheduled over decades and that not all loss types are covered, and that the reparations in place are inadequate to address vital needs such as clean water and restored livelihoods.
One of the most well-known legal cases has unfolded in a class-action lawsuit on behalf of 620,000 people filed in the UK High Court against BHP, as this company’s main headquarters were located in London and it was listed on the London Stock Exchange. The class action seeks £36 billion in damages, alleging that the company was complicit in the collapse of the Fundão dam by failing to ensure safety and oversight. Among the main allegations is that enough mine waste was released to fill 13,000 Olympic-size swimming pools, which underlines both the scale of the disaster and the degree of negligence.
Originally struck out by the High Court, the group action was reinstated when the Court of Appeal overturned that decision in 2022. As we shared earlier this year, BHP’s request to appeal to the Supreme Court was denied, clearing the way for the substantive case to proceed. The legal dispute focuses heavily on liability, design failures, monitoring negligence, and the engineering evolution of the dam – for example, how modifications (e.g. re-alignment) were implemented without full review or safety margins, and how warnings may have been ignored. The result of the case is still to be seen.
According to Finance Uncovered, the compensation sought in the class action is equivalent to almost a quarter of the combined share value of BHP and Vale. Finance Uncovered also highlights that bosses at Vale and BHP have been awarded $516 million in pay since the 2015 dam break.
Share values (market capitalisation) of BHP and Vale alongside the estimated value of damages sought in the UK class action by 620,000 people affected by the 2015 dam collapse. Image taken from Finance Uncovered.
Ten years on, the open scars remain. The disasters in Mariana and Aberfan are a sobering reminder of how industrial waste management failures ruin lives and harm communities without meaningful redress. The mining industry must finally be made accountable for its waste management. Stronger controls – national laws, international standards, enforceable liability for tailings failures – must become the norm. Without that, the Fundão dam will remain not only a tragic event of the past, but a warning of failures still to come.
Yet, over this decade, affected communities along the Rio Doce have shown extraordinary resilience by organising, demanding recognition, and refusing to let their story fade. As we mark the tenth anniversary of this disaster, we must urge BHP and Vale to restore the Rio Doce and to follow a process of reparation that truly reflects the demands and rights of affected people. Remembering Mariana is not only about mourning the past, but ensuring justice and accountability shape the future.