A £3.8 billion group action has been filed in Britain.
The case, taken by 200,000 Brazilians is against mining giant BHP Billiton, and is believed to be the largest claim in UK legal history.
Transnational SPG Law says it is seeking compensation for victims of the Samarco dam collapse in Brazil in 2015.
The collapse killed 19 people and displaced around 700, destroying the surrounding habitats.
The claim, filed in the Business and Property Courts in Liverpool, alleges failures and errors of judgment that led to the disaster.
The firm chose to litigate in Liverpool because it wanted to show that cities other than London can be an attractive forum for international dispute resolution.