Rio Tinto has agreed to fund an investigation into the impacts of the former Panguna copper mine on Papua New Guinea's autonomous region of Bougainville following complaints about the ongoing environmental and human rights impacts of the project.
Theonila Roka Matbob, a Traditional Owner and Bougainvillean MP representing the communities involved in the complaint, called the agreement an important day in the country's history.
"Our people have been living with the disastrous impacts of Panguna for many years and the situation is getting worse. The mine continues to poison our rivers," she told SBS News.
"These problems need to be urgently investigated so solutions can be developed and clean-up can begin. Today's announcement gives us hope for a new chapter for our people."
The process began last November when a group of 156 landowners made a complaint against the mining giant, alleging pollution caused by the mine infringes on their human rights.
"The mine pollution continues to infringe nearly all the economic, social and cultural rights of these Indigenous communities, including their rights to food, water, health, housing and an adequate standard of living," the claim read.
An estimated billion tonnes of mine tailings pollution has spilled into the Jaba-Kawerong river delta, with copper pollution so severe the river bank has been coloured grey-blue in places.
In 2016, Rio Tinto divested its shareholding in the mine to the Papua New Guinea and Bougainville Governments, rejecting corporate responsibility for the environmental harm caused by the mine.
The Panguna mine was majority owned by Rio Tinto and ceased operating in 1989 when it became the centre of the Bougainville Civil War.
Anger at the environmental damage and movement of mineral profits out of the country triggered an uprising and 10-year civil war that left 10 per cent of the island's population dead.
In a joint statement on Wednesday, the Australian National Contact Point for the Organisation for Economic Cooperation and Development (OECD), Rio Tinto, and the local claimants represented by the Human Rights Law Centre announced the agreement on the impact assessment.
"The Panguna Mine Legacy Impact Assessment will identify and assess actual and potential environmental and human rights impacts and develop recommendations for what needs to be done to address them," the statement said.
According to the statement, the assessment will be carried out by an independent assessor "with strong environmental and human rights expertise".
Rio Tinto chief executive Jakob Stausholm said the mining giant takes their responsibility seriously.
"This is an important first step towards engaging with those impacted by the legacy of the Panguna mine," he said.
"Operations at Panguna ceased in 1989 and we've not had access to the mine since that time.
"Stakeholders have raised concerns about impacts to water, land and health and this process will provide all parties with a clearer understanding of these important matters, so that together we can consider the right way forward."
By Sarah Smit