29 August 2022

A new independent report reviewing satellite images and other historical data on Rio Tinto's former Panguna mine has warned of serious risks to local communities posed by unstable mine infrastructure and flooding caused by the build-up of mine waste in the rivers.

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The report found that a levee at the junction of the Jaba and Kawerong rivers, constructed at the time of the mine's operation, “is almost certain to collapse at some stage in the future” and that “structures and people that live on the floodplain downstream of the Jaba River would be directly impacted by flooding or landslide effect”. The report noted that “it is not yet possible to predict when the levee at the junction of the Kawerong and Jaba rivers may fail or how severe its failure may be due to limitations of current information.”

The report also warned that “the bed of the Jaba River has raised over time due to flooding and build-up of previously deposited tailings, such as at the lower Jaba River near Bato Bridge”. This “caused the Jaba River to change course in 2017 and start to flow into the Konaviru wetland and lower Kuneka Creek, changing their flooding patterns and depositing tailings into them.” The report noted that “this change of flow into Konaviru wetland is likely to remain and become the focus of further tailings deposition in the future”, posing future flooding risks for people living in the area. However, “it is not yet possible to predict when this will happen and whether the change will be permanent".

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