Union rejects contract offer at Antofagasta’s Los Pelambres mine in Chile

Supervisors at Antofagasta’s Los Pelambres copper mine reject a contract proposal, with 94% voting against the offer. Mediation begins to prevent a potential strike.

The union representing supervisors at Antofagasta Minerals’ Los Pelambres copper mine in Chile has rejected the company’s latest contract proposal, setting the stage for possible strike action if mediation fails.

According to union leader Waldo Pérez, 94% of the union’s 550 members voted against the offer, citing insufficient improvements in key areas such as base salary, annual performance bonuses, remote work, and compensation for additional hours. The group also said the proposed terms were 14% lower than those agreed upon in the previous collective bargaining process in 2022.

Under Chilean labor law, negotiations now move into a mandatory government-led mediation period, designed to help the parties reach an agreement and avoid a strike that could disrupt operations at one of the country’s largest copper mines.

Antofagasta, which operates Los Pelambres through its subsidiary Minera Los Pelambres, said it remains committed to dialogue.

“There are still stages ahead in which we trust that, through dialogue and collaboration, we will be able to reach agreements,” the company said in a statement.

Los Pelambres, located in Chile’s Coquimbo region, produced 331,200 metric tons of copper in 2024, making it one of Antofagasta’s key contributors to total output.

If mediation fails, unionized supervisors could legally strike later this month, potentially adding pressure to global copper supply amid already tight market conditions.