By Rhiannon Hoyle

An independent assessment of an abandoned copper mine formerly owned by Rio Tinto on the South Pacific island of Bougainville found risks from unstable buildings, a potential for landslides, and contamination of soil and water around some areas, among other problems.

Rio Tinto, which offloaded its stake in the mine eight years ago, in 2021 agreed with residents of Bougainville to an independent assessment of the environmental, social and human-rights effects of the Panguna copper mine, which closed in 1989.

Rio Tinto said it is committed to helping address problems caused by the abandoned mine, which was at the center of a decadelong civil war, although communities have urged the company to go further and commit to funding remediation and tackling risks to public safety.

"While we continue to review the report, we recognize the gravity of the impacts identified and accept the findings," Rio Tinto's Australia Chief Executive Kellie Parker said Friday.

Rio Tinto said last month it signed a memorandum of understanding with the mine's operator, Bougainville Copper, and the government of Bougainville, an autonomous region of Papua New Guinea, to discuss next steps.

"We know this will take time, but we remain committed to working closely with stakeholders to ensure that the legacy of the Panguna mine is addressed in a fair and equitable manner for the benefit of impacted communities," said Parker.

Community leaders want Rio Tinto to commit to addressing the effects identified in the independent assessment and contribute to a substantial, independently managed fund to assist rehabilitation efforts, said the Australia-based Human Rights Law Centre, which represents residents.

"There are strong expectations in Bougainville that Rio Tinto will now take swift action to help address the impacts and dangers communities are living with," said Keren Adams, legal director at the Human Rights Law Centre.

Operations at the Panguna copper pit on Bougainville ended when militants, frustrated that the local community wasn't benefiting from revenues and angry about environmental damage, forced the mine to shut down.

A secessionist rebellion that led to thousands of deaths ended with a cease-fire in 1998 but the mine has remained closed.

In 2016, Rio Tinto transferred its almost 54% stake in Bougainville Copper to the governments of Papua New Guinea and Bougainville for free. Rio Tinto at that time said giving its shares to be split between the governments would allow them to work together on future options for the still-rich copper deposit.

A 2012 study by Bougainville Copper estimated it could cost more than US$5.2 billion to get the site back into operation, but that a mine there could run for roughly 24 years. It estimated Panguna could produce some 180,000 metric tons of copper and 580,000 troy ounces of gold annually.

Write to Rhiannon Hoyle at rhiannon.hoyle@wsj.com

(END) Dow Jones Newswires

December 05, 2024 17:52 ET (22:52 GMT)

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