Codelco's Chuquicamata Underground Copper Mine S04 Mining Area Commences Production in Chile

en.Wedoany.com Reported - On October 23, Chile's National Copper Corporation (Codelco) presented progress on operational adjustments at the Chuquicamata underground copper mine during the 2026 International Underground and Open-Pit Mining Conference (UMining 2026). The mine has commenced production at the S04 macro block and has incorporated the N41 and N42 macro blocks and the central mining face into its development schedule. Among these, S04 is the first macro block to enter production under a completely new plan following the mining design adjustment initiated in 2021, while N42 is the first macro block located entirely within porphyry.

Giuseppe Barindelli, Head of Geomechanics Research at Codelco's Chuquicamata Division, explained at the conference that the mine's original average ore production capacity target was 140,000 tonnes per day, and that development of the first mining level of the underground mine is currently underway. The N41 macro block has been incorporated into the production development system and is about to enter the cave mining initiation phase; the N42 macro block and the central mining face have also been included in the current development layout.

In response to rock mass stability and drift construction quality issues encountered during underground mining, the mine has adjusted certain production practices. Relevant measures include strengthening quality control for rock excavation, re-examining the mining layout for the remaining areas of the first mining level, and optimizing drift and stope designs. The medium-term operational plan focuses on the second and third production lines, specifically involving structural design adjustments to support walls, modifications to the production layout, and the establishment of a systematic rock excavation quality control mechanism. These adjustments have been implemented since 2021, with some results already applied to the development of new macro blocks.

The Chuquicamata underground mine employs the block caving mining method, with the first phase commissioned in August 2019. According to official Codelco data, the ongoing development works at the first mining level of the underground mine reached 92% construction progress in the first quarter of 2026 and further increased to 94% by the end of the first half of the year. The mine is also conducting engineering studies for the development of remaining reserves at the first and second mining levels.