Mining giant Alcoa digging up its past to keep Pinjarra plant filled

Aluminium giant Alcoa will reactivate a mine site left idle since 2014 in a last-ditch bid to replace ore from a stalled transition project and keep the Pinjarra refinery filled. The US-controlled business wants backing from the Federal environmental regulator to bring the O’Neil mine region — near Jarrahdale, south of Perth — back online for the first time in a decade. The site is located in the broader Huntly mining complex. It follows severe scrutiny of the company’s environmental management at bauxite mines in the South West, sparking work to scale back the impact on local forests and the State’s water supply. Alcoa announced plans to shut its Kwinana refinery in January in response to poor economics and a falling ore grade, shifting focus to facilities at Wagerup and Pinjarra. The submission to regulators reveals Alcoa was forced to restart mining at O’Neil because other sources of ore were delayed. “Access to the remnant bauxite ore in the development envelope is the only feasible avenue Alcoa has identified to ensure continuity of ore supply before transition to the Myara North and Holyoake,” the application said. The company said it had planned to commence infrastructure work to support the move from Huntly to the other two sites in 2023, and start digging next year. But that has stalled. “Alcoa is now targeting approval in (March quarter) 2026, with mining to commence in late 2027 or early 2028,” the document said. “It has therefore been necessary to identify an area within the Huntly Mine, from which ore can be mined in 2026, to ensure continuity of supply to the Pinjarra alumina refinery.” Alcoa said mining plans had been updated to reduce clearing and remove areas that fall within drinking water reservoir protection zones. The latest proposal would reduce clearing by 800ha, the company said. “The changes we’ve made to our plans reflect our commitment to listen to our stakeholders and the community and develop a plan that delivers improved environmental and social outcomes,” an Alcoa spokesman said. In May, The West Australian revealed Alcoa had last year told Premier Roger Cook it was “not economically viable” to stop mining areas of higher-risk to drinking water. The big alumina exporter wrote to Mr Cook when a decision on a crucial mine plan for 2023-27 was hanging in the balance. The State’s key regulator refused to endorse the plan but the State Government later signed it off, with conditions.