Rio Tinto has lodged its detailed proposal to develop the Winu copper deposit in the Pilbara, discovered in 2017, with the WA Environmental Protection Authority.
The proposed copper and gold mine is a below-the-water-table open pit that will connect to the Great Northern Highway via an 183-kilometre-long access road, over which concentrate will be trucked out for export.
Almost 5000 hectares of native vegetation will be cleared, covering critical habitat for six species including the Greater Bilby.
The clearing occurs within a 24,000-hectare development envelope, downsized in 2025 from 37,000 hectares after pushback from Traditional Owners.
The Winu mine site is remote, even by Pilbara standards. Map: Rio Tinto environmental submission
Rio Tinto majority-owns and operates the project, and Japan's Sumitomo holds a 30 per cent stake.
For decades, Rio Tinto and BHP have based their business on producing iron ore in WA. However, copper is becoming more important. In recent half-year results, the metal accounted for more than half of BHP's earnings and more than a third at Rio Tinto.
Rio Tinto already mines copper at Kennecott in the USA and Oyu Tolgoi in Mongolia. As well as Winu, it is also pursuing new copper revenue from the Resolution project in the US, which it owns with BHP.
S&P Global forecasts the world will need 42 million tonnes of copper in 2040, 50 per cent more than demand in 2025.
CORRECTION
27 August 2026 - Corrected the size of the initial and final development envelopes.
I worked in oil & gas in commercial and engineering roles for 20 years. Since 2016, I have written for The West Australian, WAtoday, The Guardian and Boiling Cold, winning five WA Media Awards.
INPEX has spilled oil into Darwin Harbour, exposed offshore workers to dangerous mercury, and been prosecuted for under-reporting toxic emissions by more than 100-fold, all in the past 12 months.
Canadian firm Vermilion judged the chance of the December spill as "rare" - the same probability it claims for seven planned exploration wells that could affect anywhere along the Pilbara coast.
