Key Highlights

  • Winu's Nyangumarta Project Agreement was signed on 8 September, and a Mining Lease was granted on 22 September.
  • The feasibility study is due around year-end for up to 10 million tonnes a year of processing capacity.
  • The Environmental Protection Authority's public review closed on 22 October.
  • Winu is a copper-gold project in Western Australia's Paterson Province.

Rio Tinto Limited (ASX:RIO) is approaching a decision point at Winu, its copper-gold project in Western Australia's Paterson Province, and the timing makes it one of the nearer-term project milestones for those watching the Rio Tinto share price. In its third-quarter operations review released on 14 October 2026, Rio Tinto said the feasibility study for processing capacity of up to 10 million tonnes a year remains on track for completion around the end of 2026. Since August, the project has also cleared several approval and community steps: a Project Agreement with the Nyangumarta Warrarn Aboriginal Corporation, the grant of a mining lease and the close of the Western Australian Environmental Protection Authority's public review period.

Where Winu Sits

Winu is located in the Great Sandy Desert, about 300 kilometres south of Broome and 320 kilometres east of Port Hedland. Planned operations sit on Nyangumarta Country, while the Karlkayn airstrip is on Martu lands. Rio Tinto is the managing partner and operator, and Sumitomo Metal Mining holds a 30% Equity interest in the project. The proponent for environmental approvals is Winu Services Pty Ltd, a Wholly Owned Subsidiary of Rio Tinto Limited.

The project would be a new copper-gold mine, and Rio Tinto has said operations are planned to run largely on renewable energy, including solar and wind supported by battery storage. Winu would be the first mining operation on Nyangumarta Country.

Recent Milestones

The Project Agreement with the Nyangumarta Warrarn Aboriginal Corporation was signed on 8 September 2026, which Rio Tinto described as a key project milestone. The company announced the agreement on 10 September. The mining lease was granted on 22 September 2026.

On the environmental front, the Environmental Protection Authority released the Environmental Review Document for public review on 27 August 2026, and submissions closed on 22 October 2026. Winu is being assessed as a Public Environmental Review, the highest level of assessment in Western Australia. Approvals are also progressing under the federal Environment Protection and Biodiversity Conservation Act, with a further public comment opportunity to follow at a time set by the federal environment department.

What Remains Unresolved

Rio Tinto said Project Agreement negotiations with the Martu Traditional Owner Group remain its priority, and that discussions continue to secure airstrip and water access. The company's project page states that mining will not proceed unless it obtains the free, prior and informed consent of Traditional Owners.

The pathway also remains subject to regulatory and other required approvals. Under the Western Australian process, the proponent responds to public submissions, after which the Environmental Protection Authority prepares an assessment report with recommendations for the state environment minister. The report is published and is open to appeal before the minister makes a final decision on whether the proposal may be implemented and on what conditions. The federal process runs separately, although the two can be coordinated. These steps mean environmental approval is unlikely to be the only Factor setting the pace, with Traditional Owner agreements and the feasibility study outcome also shaping timing. Rio Tinto has not announced a final Investment decision timetable, Capital cost or production rate for Winu, and the feasibility study is the next step before any such decision.

Exploration also continues, with Rio Tinto noting that full potential exploration drilling is underway at the project. Further drilling results could influence the scale and sequencing assumed in later studies, although Rio Tinto has not linked the current feasibility work to any change in the resource base.

Why Winu Matters for Rio Tinto's Copper Strategy

Copper is central to Rio Tinto's growth plans. The company's consolidated copper production was 646,000 tonnes in the first nine months of 2026, and full-year guidance is 800,000 to 870,000 tonnes. Third-quarter output of 205,000 tonnes was flat on a year earlier, and copper C1 net unit cost guidance of 30 to 50 US cents per pound reflects the benefit of higher gold by-product prices. That gold Credit is relevant to Winu, which as a copper-gold deposit would also generate gold alongside copper. Most of that growth has come from Oyu Tolgoi in Mongolia, which Rio Tinto expects to produce about 500,000 tonnes a year on a 100% basis between 2028 and 2036.

Winu would add an Australian source of copper and gold within a Jurisdiction where Rio Tinto already runs large-scale iron ore operations in the Pilbara. Rio Tinto's other large undeveloped copper option, Resolution Copper in Arizona, still faces the possibility of a further US Supreme Court appeal on its land exchange, so Winu offers a development pathway in a different jurisdiction with its own approval timeline.

Capital Allocation Context

Any decision on Winu would be weighed against Rio Tinto's other capital commitments. The company's share of Capital Investment was US$5,037 million in the first half of 2026, with spending on Simandou in Guinea, Oyu Tolgoi, lithium projects in Argentina and the planned Kangwinan bauxite project in Queensland. At the same time, Rio Tinto is pursuing around US$5 billion of capital release by the end of 2026 and a US$1.8 billion annualised productivity run-rate target. How Winu ranks within that pipeline will become clearer once the feasibility study is complete.

Key Takeaways

Winu has moved forward on several fronts since August, with the Nyangumarta Project Agreement signed on 8 September, a mining lease granted on 22 September and the Environmental Protection Authority's public review closing on 22 October. The feasibility study for up to 10 million tonnes a year of processing capacity is due around the end of 2026, while agreements with the Martu Traditional Owner Group on airstrip and water access, as well as state and federal environmental approvals, are still to be finalised. For those watching the Rio Tinto share price, the feasibility study outcome and any update on the Martu negotiations are the next markers for whether Winu can progress towards an investment decision.