Santiago, July 31, 2026 - With deep respect for the memory of the six workers who died in the accident at the El Teniente Division on July 31, 2025, Codelco commemorated this Friday the first anniversary of one of the most painful days in its recent history.

The various activities were aimed at remembering the deceased workers, supporting their families, and reflecting with our own employees and those of collaborating companies on the importance of continuously strengthening safety in all operations.

The ceremonies began at 8:00 AM during all shift changes inside the El Teniente mine, with reflection periods that were repeated at the start of shift changes in all divisions, also extending to staff work teams.

At 08:30 AM, the executive committee of El Teniente, led by the general manager (i) Gustavo Reyes, along with the vice president of Operations (i), Lindor Quiroga and the corporate manager of Security, Jorge Camhi, as well as divisional workers and union representatives, collaborating companies and other internal stakeholders , met in the Sub-6 Plenary in a meeting that was broadcast to the entire workplace.

At 10:00 AM, meanwhile, the Head Office held a commemoration in which the Chairman of the Board, Bernardo Fontaine, the CEO, Jorge Gómez, the Vice Presidents and the managers that make up the corporate executive committee participated, in addition to the workers of this work center and representatives of the Federation of Copper Workers (FTC), the Federation of Copper Supervisors (Fesuc), the National Association of Copper Supervisors (Ansco) and the unions of the Head Office.

During the day, a commemorative plaque with the names and photographs of the deceased workers will be installed in the Sewell locker rooms. This event will be attended by divisional and contractor employees, as well as a group of executives.

Finally, at 5:34 p.m. sharp, the time the accident occurred, the entire El Teniente Division will observe a minute of silence.

One year after the accident, the Corporation reaffirms that honoring the memory of the deceased workers requires a sustained effort to strengthen safety, learn from what happened, and continue improving risk management to protect the lives of those who work in its operations.

The work carried out this year

Regarding the work undertaken by the Corporation this year, the various investigations stand out, aimed at clarifying the facts, gathering lessons learned, and strengthening the capacity to prevent this type of accident. Among these, the Codelco Internal Investigation Commission and the International Expert Group convened by the board of directors—led by Mark Cutifani, former CEO of Anglo American—were particularly noteworthy. Their recommendations have guided new measures to deepen the geotechnical understanding of the deposit, reinforce monitoring systems, and elevate safety management to the highest levels of the organization, incorporating a comprehensive approach that combines technology, operational discipline, and on-the-ground leadership.

Among the main measures implemented are the redefinition and expansion of the preventive seismic monitoring zones; the updating of standards associated with risks of fatality from explosions and rockfalls; the strengthening of safety and evacuation areas; new training opportunities for workers and supervisors, in addition to periodic inspections that include the participation of Sernageomin along with internal teams.

The El Teniente Division also created the Studies and Methods Management, a unit dedicated to capturing and applying the lessons learned from research, while advancing in new drilling campaigns, state-of-the-art seismic instrumentation, advanced rock mass modeling and evaluation of technologies that allow for better anticipation of the risks associated with deep mining, in one of the most complex and challenging underground operations in the global mining industry.

In parallel, Codelco has maintained ongoing collaboration with the authorities throughout the investigations. For nearly eleven months, it responded to 30 requests for information from the Public Prosecutor's Office, providing more than 14,000 technical documents, in addition to facilitating on-site inspections and investigations. Sernageomin, the agency, has conducted more than 60 inspections since the accident, a process that has strengthened institutional coordination and contributed to clarifying the facts.

Codelco