Chile’s Labor Directorate has sanctioned the partial and gradual resumption of underground activities at the El Teniente mine, operated by state-owned Codelco, following a collapse triggered by a recent earthquake that claimed six lives.
Operations remain halted in certain sectors while others have been approved to restart under strict safety protocols.
The earthquake-induced collapse, which occurred on July 31, 2025, led to the suspension of operations in specific underground areas due to structural instability and safety concerns.
The approved sectors for resumption include Dacita, Diablo Regimiento, Esmeralda, Esmeralda Panel, Pilar Norte, Reno Panel, Reservas Norte, and Upper Pacific, while operations remain suspended in Recursos Norte, Andesita, Andes Norte, and Diamante.
Codelco has implemented a comprehensive return to work plan emphasising safety and communication.
This includes reflection sessions at the start of shifts focused on the return strategy, support measures, safety protocols, and supervisory oversight.
The plan also mandates two-way communication within the mine and enhanced presence tracking using advanced systems such as Tracking & Asset Management and Tipping Point Management.
Additional safety measures involve personal protective equipment checks, reviews of habitability conditions, ongoing updates on seismic activity, union information dissemination, and coordination with partner companies to ensure all personnel are fully informed.
The phased reactivation began with Shift C, involving 710 workers with 131 entering the mine, followed by Shift A with 1,770 workers actively engaged in reactivation duties.
Ore shipments to the processing plant during this initial phase have been approximately 50 per cent below normal levels, although processing plant and smelter operations have been fully restored.
Government oversight remains active, with two inspectors from the Chilean mining regulatory agency Sernageomin recently conducting evaluations in the Andes Norte sector.
Codelco has also been responsive to 21 inquiries from various regulatory and investigative bodies, including the Attorney General’s Office, the Chamber of Deputies, the Labor Directorate, the PDI (Investigations Police), the Regional Ministry of Health, and Sernageomin.
Meanwhile, Codelco’s Internal Investigative Commission continues to meet to determine the precise causes and circumstances of the collapse, which appears likely to be related to mining-induced seismicity rather than a purely natural earthquake.
The mine, located approximately 2,400 metres underground in the Andes mountains, is one of the largest underground copper mines globally, contributing significantly to global copper supply.
The incident has had a notable impact on production and raised serious questions about underground mining safety in seismically active regions.
