South32 (ASX:S32) achieved record plant throughput after it completed its de-bottlenecking project within its 45%-owned Sierra Gorda copper mine in Chile, which is expected to drive further growth, according to a Thursday filing with the Australian bourse.

The project increased throughput by 30% to 49 million tonnes per annum following a series of improvements to the concentrator, the filing said. Its estimated capital expenditure for fiscal 2025 is $210 million, including $25 million earmarked for fourth-line study work in the first half.

South32 said there is a potential to expand capacity by 20% through a fourth grinding line.