Harj Narulla and Tim Cooke-Hurle instructed in historic Municipio de Mariana v BHP Group case establishing liability involving 620,000 Brazilian claimants seeking £36bn in damages

Harj Narulla and Tim Cooke-Hurle have acted as counsel in the landmark Municipio de Mariana v BHP Group [2025] EWHC 3001 (TCC) litigation, which is the UK’s largest ever environmental claim.

On Friday 14 November, the High Court handed down a judgment establishing BHP’s liability for the 2015 Fundão Dam collapse in Brazil which devastated over 700km of river ecosystems and impacted hundreds of thousands of victims. The collapse is regarded as Brazil’s worst ever environmental disaster, resulting in the release of 40 million cubic meters of toxic tailings.

Following the stage 1 proceedings focused on liability, the High Court upheld the claimants’ arguments establishing fault-based and strict liability on behalf of BHP, an Anglo-Australian mining company. The case applied the Brazilian Civil Code and Brazilian Environmental Law.

During 2025, Harj was instructed by Pogust Goodhead in relation to stage 2 of the proceedings, dealing with issues of causation and quantum. He focused in particular on the nearly 30,000 indigenous and afro-descendant Quilombola communities that form part of the claim.

In 2019-2020, Tim Cooke-Hurle was instructed to advise the Claimants on the strategic management of these complex, multi-claimant proceedings. His advice also addressed jurisdictional issues, the procedural challenges of international evidence, and the instruction of Brazilian legal experts. His recommendations focused on effective approaches for the English courts, the preparation of witness and expert evidence, and the management of large-scale transnational claims.