Tailings dams at Telfer gold mine in the Pilbara still a headache for Newcrest, environmental regulators

Newmont and environmental regulators are still working to fix two troubled tailings dams at the Telfer gold mine, months after production was switched off.

The US-owned company shut down the Pilbara processing mill twice in the past eight months because of problems at the dams — and the plant has been out of action since April.

The reservoirs were used to store waste products from mining and processing gold.

Newmont was issued a directive by the Department of Water and Environmental Regulation in late June, armed with concerns the wastewater would cause pollution.

The notice specifically gave Newmont 30 days to empty the dams but The West Australian understands the reservoirs had already been drained following an emergency order months earlier.

The order requires Newmont to keep the dams empty until leaks have stopped.

It’s not clear how much has seeped from the dams or exactly what is in the wastewater.

But documents previously lodged with the Environmental Protection Authority related to the Telfer plant suggest the tailings were expected to contain chemicals including cyanide and sulphate, common byproducts of gold processing.

A spokesman for DWER said the latest directive “facilitates the continued dewatering of (the dams) as necessary”.

He also said the notice would ensure the company “can continue to undertake required emergency engineering and maintenance works.”

A Newmont spokeswoman confirmed production had been suspended since April this year.

“All water has already been removed from both (the dams) TSF7 and TSF8 following engagement in April with DEMIRS and full remediation is underway,” she said.

“Newmont is working to bring Telfer back into production safely, responsibly and as quickly as possible.”

Worksafe said an investigation into the Telfer tailings trouble was ongoing.

“Prohibition notices for the tailings storage facilities at the mine remain in place,” a spokesman said.

Telfer had been operated by Newcrest until the business was acquired by Newmont in a whopping $26 billion deal in October last year.

Newmont swiftly moved to put the site and a series of other mines up for sale with a price tag of roughly $3b, labelling the operation a “non-core asset”.

But the tailings troubles have been a headache at the 47-year-old operation, which in the 2023 financial year produced about 350,000 ounces of gold.

The site was first shut for seven weeks in December amid what was understood to be soil erosion problems.

Premier Roger Cook weighed in at the time to say it was “a very concerning development”.

Newcrest hit major trouble in New South Wales in 2018 when the wall failed at the Cadia northern tailings dam.

That reportedly caused huge emissions of dust, potentially including silica, into nearby communities.

A 2023 statement from the NSW EPA said the company was “issued two penalty notices and two pollution reduction programs in relation to the tailings dam wall failure”.

The NSW EPA also moved to prosecute Newcrest Cadia Holdings in October 2023.