Mining giant BHP liable for Brazil’s worst environmental disaster, UK court says

London's High Court ruled Friday that global mining giant BHP Group is liable over the 2015 collapse of a dam in southeastern Brazil. 

"BHP are strictly liable as 'polluters' in respect of damage caused by the collapse," of the dam, the court said in its ruling following a large-scale trial. 

Hundreds of thousands of Brazilians, dozens of local governments and around 2,000 businesses sued BHP over the collapse of the Fundao dam in Mariana, southeastern Brazil, which was owned and operated by BHP and Vale's Samarco joint venture.

Brazil's worst environmental disaster unleashed a wave of toxic sludge that killed 19 people, left thousands homeless, flooded forests and polluted the length of the Doce River. 

Judge Finola O'Farrell said in a summary of her ruling that BHP should not have continued to raise the height of the dam before its collapse, which was "a direct and immediate cause of collapse of the dam giving rise to fault-based liability on the part of BHP". 

Read moreThe Mariana mining disaster

According to the victims' lawyers, BHP was aware that toxic sludge was accumulating at rates that far exceeded the annual limit. The lawyers said the build-up contributed to the disaster at the mine, which was managed by Samarco, co-owned by BHP and Brazilian miner Vale.

BHP argued during the trial that it had prioritised safety and acted responsibly.

Acknowledging the "terrible tragedy", BHP maintained that a compensation agreement it reached last year in Brazil – worth around $31 billion – provided a resolution. However, a majority of the 620,000 claimants, including 31 municipalities, argued that they were not sufficiently covered by the deal. 

BHP said it would appeal against the ruling and continue to fight the lawsuit. 

The victims first filed the UK legal action in 2018 to demand compensation from BHP, as one of its global headquarters was in Britain at the time of the disaster. 

The trial at the High Court in London ran from October 2024 to March this year. 

Vale and BHP were acquitted in November 2024 of criminal charges by a Brazilian court, which ruled there was insufficient evidence linking them to the dam's failure. 

(FRANCE 24 with Reuters, AP and AFP)