Los Pelambres Mine! It’s one of the largest copper mines in Chile, located in the Coquimbo Region in the Andes mountains, roughly 200 km north of Santiago. It is operated by Antofagasta PLC, a major Chilean mining company, and it has been producing copper concentrate since the late 1990s.
Los Pelambres is known for its substantial copper and molybdenum reserves, as well as its commitment to sustainable practices, such as water reuse and renewable energy initiatives. The mine faces some significant challenges, including complex rock formations, high altitudes, and water scarcity in the region, which has led to innovations like a pipeline that brings seawater for processing. It’s also noted for its large-scale open-pit operations and advanced infrastructure, which includes one of the longest conveyor belts in mining and a complex system of tunnels and pipelines to transport ore and concentrate.
Los Pelambres hosts a significant porphyry copper-molybdenum deposit, with copper sulfide minerals like chalcopyrite and bornite being the primary sources of copper. It also contains molybdenum as a valuable by-product. The deposit is characterized by mineralization within quartz veins and breccia structures, formed from the intrusion of granodiorite and other igneous rocks associated with the Andean orogeny (mountain-building process).
Los Pelambres is a large-scale open-pit operation with multi-stage blasting and bench mining to extract the ore. Given its high-altitude location, careful attention is paid to slope stability and pit design. The mine processes the extracted ore via crushing, milling, and flotation to produce a high-grade copper concentrate. The molybdenum by-product is separated in a subsequent flotation process. With annual production typically around 350,000–400,000 tonnes of copper, Los Pelambres is one of the largest copper producers in Chile. The molybdenum output is also significant, adding economic value to the operation.
The mine features one of the longest overland conveyor belts in the world, stretching over 12.7 km. This system transports crushed ore from the pit to the concentrator and is a crucial part of reducing truck haulage within the mine. The copper concentrate produced is pumped through a 120-km pipeline to the port of Los Vilos for shipment. This system, which crosses mountainous terrain, minimizes environmental impacts from road transportation. Given the arid environment, water is a critical resource. The mine has implemented extensive water recycling measures, achieving a high recycling rate. Additionally, a pipeline brings seawater from the coast, which is desalinated for use in processing.
The mine’s location at 3,200 meters above sea level poses logistical challenges for transporting materials and maintaining workforce health. Water management remains an ongoing challenge, pushing innovation in desalination and recycling. Los Pelambres has invested in improving its tailings management systems, focusing on both safety and sustainability. Tailings are thickened and stored in a dam, with continuous improvements to address seismic risks in the Andes.
