Focus on the environment

We strive to produce in a sustainable way based on a long-term vision. Our priority is to prevent, minimise and mitigate adverse impact on the environment in which we operate. Through regular reports and reviews, we periodically evaluate our performance and conduct improvement action as required. Our four operations meet all the criteria of The Copper Mark and the ICMM Performance Expectations standards for responsible mining.


  • 0 operational events with significant environmental consequences
  • The Copper Mark validation seal for Antucoya and Los Pelambres
  • +US$ 2 billion Los Pelambres desalination plant enters the testing phase and a project to double its capacity is approved
  • US$ 4,400 million Investment approval of Centinela Second Concentrator project and its use of 100% seawater

Our Environmental Management Model covers leadership, operating risk management, regulatory risk management and reporting of operational events and environmental findings.

Our model is integrated across our companies, in order to identify and mitigate risks and to comply with environmental regulations across the Group, including in our current operations, in our land explorations, and in projects in development. As part of this, we identify learning opportunities and share them with all our companies.

We advise on project design and improvement from the environmental and sustainability perspective, particularly regarding early dialogue within the communities in which the project is operating. The inclusion of all these elements facilitates the processes involved in applying for environmental permits.

Our environmental performance is reported monthly to the Executive Committee and twice a year to the Board’s Sustainability and Stakeholder Management Committee. Based on an Annual Audit Plan, the Internal Audit area performed environmental audits on all our operations in 2023. These were conducted to verify the effectiveness of our internal controls and governance, compliance with environmental requirements, and the measures committed to by our operations within the framework of their environmental permits. No significant audit findings were reported.

We consistently strive to work as closely as we can with the relevant authorities to receive any feedback they may offer is the basis for our continued improvement. We are engaged in early dialogue with the surrounding communities through Early Community Participation (Participación Ciudadana Anticipada).

Antofagasta Minerals

  • 71 RCA (environmental permit), including our Transportation Division
  • 10.000+ commitments
  • 4 main areas (water use, air quality, biodiversity, and project construction, operation and closure)

In Chile, large-scale projects must be assessed by the Environmental Evaluation Service (SEA) and awarded an environmental permit called RCA. These RCA include legally binding commitments on matters relating to the prevention and mitigation of the projects and any significant impacts on the environment and communities, and if applicable any necessary compensation actions. Compliance with commitments is verified by the Superintendency for the Environment (SMA).

Operational events with environmental consequences are classified as Actual (high, medium or low) or Potential (high or low) according to the specific features of each. A dedicated internal committee investigates actual high- or medium-severity events.

According to the criteria established in the environmental assessment of each operation or project, we had zero operational events with significant environmental consequences. A total of 30 events with no severe environmental consequences were reported to the Environmental Authority in 2023.

In October 2023, Los Pelambres received approval from the Coquimbo region’s Environmental Evaluation Commission for a US$ 2.2 billion project that will double the capacity of the desalination plant to 800 litres/second, allowing production processes to start using mainly desalinated water. In addition, the project involves the construction of a new copper concentrate transportation system via routes far from populated areas, along with continuity works in the El Mauro tailing.

In November, the SEA approved the DIA (Environmental Impact Assessment) of the “Centinela District fuel storage capacity increasing” project. With an investment of US$ 25 million, the initiative seeks to increase the fuel supply for haul trucks and vehicles at the mining site. The project will allow autonomous operation for ten days.

Tailings deposits are a central issue for Antofagasta Minerals and accountability for them lies at the highest levels of the Company’s management. Our Tailings Policy is aligned with the Global Industry Standard on Tailings Management (GISTM), and we prioritise the safety and health of our personnel, neighbouring communities and the environment.

Tailings risk management involves periodic risk assessments, controls and mitigation measures to prevent and minimise any negative events.

GISTM Framework 

The GISTM provides a framework for safe management of tailings facilities. The standard is classified by topic, covering various areas that together require assignment of responsibilities and prioritisation of the safety of each tailings facility throughout all phases of the project lifecycle, including closure and post-closure.

Areas covered

  • communities
  • knowledge base
  • design
  • construction, operation, monitoring and closure
  • management and governance
  • emergency response
  • public disclosure
  • principles and criteria

In line with GISTM, we have achieved a high standard of safety, and appropriate governance is in place to ensure that our companies are working on applying the proper tailings water reduction technology – as is the case with thickened tailings at Centinela – and on ensuring that tailings deposits are safely managed to guarantee their physical and chemical stability.

As required by the GISTM, self-assessment at two of our four main tailings facilities – the El Mauro dam at Los Pelambres and the Centinela thickened tailings deposit at Centinela – was completed in August 2023, and compliance with the standard was announced. They will undergo third-party validation as soon as reasonably practicable. Los Quillayes and Zaldívar’s small thickened tailings deposit will publish compliance by August 2025.

Implementation of the standard requires collaboration between various areas of the companies, which must conduct studies and update information on each tailing’s facility, as well as stronger relationships with communities through the transparency and sharing of information.

We are safety leaders in tailings management within the global mining industry. Centinela has one of the world’s largest thickened tailings deposits in terms of size and production. At Centinela, the percentage of solids is low and the material is dense enough to walk on. In parallel, Centinela has worked on a preventive emergency plan with the community of Sierra Gorda, the first municipality in Chile to have a natural hazard emergency simulacrum.

The four main tailings deposits undergo an Independent Review annually (council of independent reviewers for Los Pelambres and Centinela; single independent reviewer in Zaldívar). In 2023, their stability was again confirmed according to international criteria. Between 2022 and 2023, a geotechnical characterisation campaign was carried out for the Quillayes tailings deposit, finding low tailings humidity, which significantly reduces the risk and impacts associated with the deposit.

Learn more:

El Mauro (Los Pelambres)

Thickened Tailings Deposit (Centinela)

On 17 February 2023, the SMA issued a fine of UTA 211.9 (US$ 196,202) having established that two of the three infractions identified during the sanction process were associated with the water leak from an emergency pool, part of the Los Pelambres tailings transportation and water recirculation system, located in the municipality of Salamanca. The fine was paid in 2023.

In 2023, we launched our Circular Economy Strategy, approved at the end of 2022. Its three pillars are linked with four priorities: regulations and trends; engaging with stakeholders; innovation; and circular economy culture.


  • Reducing resource usage
  • Expanding the lifecycle of material and equipment
  • Converting waste into new resources

In 2023, we asked our companies to share solutions and proposals, to coordinate our environmental, supply and innovation areas in an effort to increase the visibility of what we do and promote new initiatives within circular economy.

Innovation and collaboration have been essential elements in boosting our Circular Economy Strategy, supervised by our Circular Economy Committee. We began the implementation of this strategy by taking into consideration packaging material, pallets and the logistics of goods transportation, as well as the reuse of tyres, steel, lubricating oils, water and energy.

In 2023, the Group generated 556 million tons of waste, most of which corresponded to mining waste, and a smaller fraction was industrial and domestic waste.

The generation of mining waste increased by 1% compared to 2022 due to the increase in tailings and waste, the depth at which extraction has reached, and the low copper grades, which means that a more significant amount of material has been processed.

The recovery of industrial waste increased by 46% compared to 2022, as greater quantities of lubricating oils, drip lines, lead batteries, lead deposits, belts, scrap metal and out-of-use (NFU) tyres were recycled.

Each of our mines operates comprehensive programmes to control dust emissions, PM10 and PM2.5. These emissions are subjected to periodic surveillance, in some cases involving the local community. Air quality data is regularly reported to the regional authorities to ensure compliance with environmental regulations.

At Antucoya, we have implemented measures to mitigate the emission of particulate material, both at the site and across our facilities. The main course of action has been the development of a dust collection system, which is currently being installed. The system controls emissions from the secondary crushing system and transfer tower, and has received an initial investment of $50 million.

At the Quillayes TSF, Los Pelambres has planted 96,000 native trees and shrubs on the 300-hectare site, of which 120 hectares have been planted so far. The vegetation requires little irrigation, easily adapts to extreme environments, and serves to control particulate material events while blending the dam with its surroundings.

 Read more about our Environment in our Sustainability Report 2023