Impacts of Ore Extraction
- As with any resource that is extracted from the ground, careful consideration needs to be given to how it impacts the environment
- Mineral ores are often extracted using open-pit mines
- These have a large impact on habitats and groundwater
- Processes used to refine the ore can introduce toxic chemicals into the area
- Copper extraction has a large impact due to the fact that it is mostly extracted and processed in one place
CASE STUDY - Copper mining in Chile
- Chile is the top copper producer globally with 29% of market share
- Production is mainly located in the northern part of of the county
- Chile’s largest copper producing companies are the state-owned Codelco and British multinational Antofagasta
- Due to exports, Chile is now one of two high-income Latin American economies
- However, copper mining impacts the environment, through sheer size, water and air pollution
- Vast areas are deforested, with open cast mining extending to several kms in width and depths can exceed thousands of kms
- The sloping nature of the open mines, along with exposed topsoil increases mass movement
- Mining dust increases respiratory disease and high levels of arsenic have been found in the blood of workers
- Environmental regulations surrounding operations of Codelco are poor, resulting in heavily polluted mining environments
- Extraction of copper from its ore involves crushing, dissolving, filtering and smelting
- These processes produce large quantities of of contaminated waste water and frequently washes into local watercourses affecting drinking water and ecosystems
- Large amounts of energy is needed and many of the mines have their own power stations running on coal, increasing greenhouse gas emissions
- Processing requires quantities of water, but most of the mines are in high altitude deserts and water has to be pumped to the site
- Seawater is desalinated at an environmental and economical cost and then piped to the mine, increasing costs
- Acid rain is produced as a result of smelting, which releases sulphur dioxide into the atmosphere
Location of copper mines in Chile and their environmental impacts
- Over-extraction of water from underground aquifers, lowering the water table and denying local rural communities source of water from wells
- Contaminated water discharged into local drainage systems: large volumes of water, required for processing copper ore are contaminated with rock waste and toxic minerals
- Coastal pollution: pollution of coastal waters from blown dust, transfer spills and oil discharge from the ore carriers loading up for export
- Air contamination from dust: dust from waste piles lead to breathing issues in the dry air of the Andes
- Emissions from transport of ore to docks: can create significant amounts of dust, noise, congestion and vehicle emissions
- Due to the intensity of pollution around the Chuquicamata mine, the settlement housing workers and families of the mine was closed in 2003 and residents transferred to the town of Calama,16 km away