"Alcoa was warned for years about Perth water threats, so why is our biggest dam at risk?", 09 February 2023

"The West Australian government continued to approve Alcoa’s bauxite mining practices, which threaten Perth’s drinking water supply, despite its own departments raising grave concerns about the issue for at least two years.

This masthead can also reveal that the US aluminium giant’s latest mining plans have not met strict expectations set by State Development Minister Roger Cook.

Internal government advice obtained by this masthead exposed serious fears that Alcoa’s mining practices near the Serpentine Dam left the water vulnerable to flows of pollutants and disease-causing pathogens from mining sediment in the event of heavy rainfall.

Alcoa experienced 227 drainage failures and spilled more than 100,000 litres of diesel and hydraulic oil over the past five years including in water catchment zones throughout the Darling Scarp.

A large sediment flow into the Serpentine Dam, which provided 18 per cent of Perth’s drinking water last year, could potentially shut it down for years and result in billions of dollars of taxpayers’ money spent to fix the problem...

An Alcoa spokeswoman said the company operated according to its mining and management programs, took its responsibilities seriously and its mining operations had never impacted drinking water supply.

“We continue to work cooperatively with relevant government bodies to address evolving expectations for environmental management,” she said..."