Air Quality Management  

Mining generates particulate matter emissions that stick to airborne dust generated by natural causes. Maintaining air quality is key to protecting the health of workers and local communities.

OUR APPROACH

Antofagasta Minerals takes a preventive approach to particulate matter emissions, using weather forecasts and emissions predictions to help focus operating controls, which range from wetting roads, covering conveyor belts and stockpiles to, when necessary, rescheduling mining activities.

All of the operations monitor air quality in their camps and in nearby communities. This is a particular issue for Los Pelambres and Centinela, which are located close to populated areas, and both operations have an early warning system to prevent critical air quality events caused by adverse weather conditions.

Antofagasta Minerals is constantly seeking new solutions for maintaining emissions levels below the limits set in the standard on particulate matter.

The operations have adopted various operating measures to reduce their particulate matter emissions. Los Pelambres, for example, uses mist canons and road-wetting to reduce dust levels in the mine area and together with Centinela, it also uses moistening foam and sprinklers in the plant, on stockpiles and on conveyor belts. Both Los Pelambres and Centinela have developed predictive models to anticipate weather phenomena that, when combined with certain operating conditions, might affect air quality. Measures can then be taken to prevent higher concentrations of particulate matter in the air, for example, if strong winds are forecast, activities involving explosives at the mine can be rescheduled.

Due to distance, wind and topography, particulate matter emitted by Centinela does not significantly affect the town of Sierra Gorda. But in response to a gradual deterioration in the community’s air quality, a public-private working group was set up to address the problem. This is led by the local council and includes the Health Agency, the Ministry of the Environment and the four mining companies operating in the area.

In 2016, the Sierra Gorda Air Quality Study framework made progress in identifying emission sources, proposing additional or alternative mitigation techniques, assessing measures to be implemented by the companies to reduce emissions and informing the community of the results. Air quality is measured in terms of the concentration of particulate matter at monitoring points jointly agreed with the authority. In 2016, emissions remained below the maximum level permitted for air quality in residential areas. At Los Pelambres, the community will continue to participate in monitoring.

Average annual concentration of PM10 micrograms per m3N201420152016
Los Pelambres 46 37 35
Centinela 39 40 34
Antucoya* n/a n/a n/a
Zaldívar     97

 

* Not available, as Antucoya has no stations that are representative of the population.