Mining Corporation Codelco Pursues Partial Resumption of Operations at El Teniente Mine Following Deadly Collapse Incident
The El Teniente mine, one of Chile's most significant mining operations, was halted following a deadly collapse on July 31, 2025. The incident claimed the lives of six workers and has raised questions about the structural integrity of older sections of the mine and the adequacy of current fortification systems.
The collapsed area is believed to be part of the Andesita section of the mine, a strategically important component of El Teniente's expansion, which includes the Andes Norte and Diamante projects. The Andesita development is intended to help offset declines in older zones and maintain output levels through the next decade.
Codelco, Chile's state-owned copper giant, has requested approval to restart parts of the El Teniente mine. However, mining operations were formally suspended by Chile's geology and mining agency, Sernageomin. Mining Minister Aurora Williams has ordered a temporary cessation of activities at the mine. Sernageomin has instructed Codelco to submit four comprehensive technical reports before any restart can be authorized.
The accident was triggered by a 4.2-magnitude seismic event. No formal complaints about the safety conditions of the site have been received, but a full investigation and appropriate corrective measures are underway. The cave-in occurred more than 900 meters underground and initially trapped five miners. Their bodies were recovered over several days by a rescue team, including veterans of Chile's 2010 San Jose mine rescue.
Codelco's chairman, Maximo Pacheco, has confirmed that international experts will be involved to determine the cause and assess any operational failures. Additionally, Chile's Public Prosecutor's Office has launched a criminal investigation to evaluate whether safety standards were breached during mining activities.
Regarding the planned international audit of Codelco’s safety standards, while explicit details or timelines of such an audit have not been publicly specified, the commitment to involve international experts suggests an upcoming comprehensive external review of safety practices and protocols at El Teniente.
Operationally, Codelco began a gradual restart of the mine on August 10, reopening eight underground areas considered safe by authorities, covering about 82% of production capacity. However, four sections near the collapse site remain closed as investigations continue and damage assessments proceed. The Public Prosecutor’s Office has reported extensive damage to approximately 3.7 kilometers of tunnel, far exceeding initial estimates, underscoring the severity of the incident and the importance of thorough investigation and remediation.
The El Teniente mine, located about 100 kilometers south of Santiago in the Andes mountains, is a cornerstone of Codelco's operations and Chile's mining economy. In 2024, El Teniente produced 356,000 metric tons of copper, nearly 7 percent of Chile's total output. The mine contains a labyrinth of more than 4,500 kilometers (2,800 miles) of tunnels.
The accident at El Teniente is a significant setback for Codelco as it seeks to modernize its aging infrastructure and boost production after years of underinvestment. Though Chile boasts one of the world's safest mining sectors, the string of incidents at Codelco sites has drawn concern from unions and regulators alike. The investigation into the cause of the El Teniente mine collapse is ongoing.
The incident at the El Teniente mine, a significant component of Chile's mining sector, has prompted questions about the structural integrity of older sections and the adequacy of current fortification systems in the mining industry. Given the importance of the Andesita development in maintaining output levels and offsetting declines in older zones of the mine, the investigation is also expected to delve into the safety standards and operational practices within the finance and energy sectors, which are integral to the mining operations.
