Open-pit mining is surface mining done in the open atmosphere with the mechanical method. And thus, open-pit mining has a lot of devastating effects on the environment.
According to a study, open pit mining exposes 8 to 10 times more waste materials to the environment than underground mining. These effects substantially affect the soil, water, air, and living beings near the mining area.
Moreover, here in this article, we will share open pit mining and the environmental problems it causes. So. Let’s understand.
Table of Contents
What is Open Pit Mining?
Open-pit mining is a process of digging the earth’s surface to extract ores or minerals present in a shallow layer. In case of mineral ores present deep down, we require an underground tunnel to remove them. That’s not under an open atmosphere like open-pit mining.
The shape is already determined and optimized for maximum profit in surface mining. Non-coal materials are the target of open-pit mining almost every time. However, it also relies on the type of mineral ore deposit.
Based on the ore deposition type in a specific area, we can categorize the deposits as massive and steeply pitching.
In open-pit mining, the mining starts by examining the type of deposit, and the shape always looks like a cone. As the deeper the mining process reaches, the more costly it demands the transportation of the mineral ores from the mine site to the plants.
Here we use horizontal branches, exposing mineral ores to the concave surface. Sometimes, the toxic chemicals that usually remain in low quantity in the soil get exposed to the air, water, and earth, which is highly devastating for the atmosphere.
Dumping the Overburden (OB) and transporting the mineral ore both are done through the same equipment in open-pit mining.
6 Environmental Effects of Mining
As we understand what open pit mining is, let’s dive deeper into why it is so devastating for the environment. Here we have six problems and effects of surface mining.
Soil Erosion and Pollution
It is almost common to all types of surface mining. To access the mining area for excavating the minerals, we destroy the surface soil, rocks, and available vegetation. It eliminates the topsoil and causes soil erosion.
On the other hand, the rocks that were otherwise deeply buried get exposed to the atmosphere. After being broken and polished, these rocks eliminate harmful chemicals and radioactive substances. It highly affects the soil of that area and the nearby region, too.
Other reasons for the land damage and degradation include excavating mineral ores and damping the overburden.
Unregulated mining practices lead to a massive effect on our water bodies. Sometimes mine construction causes the water bodies to disturb. The overburden produced and damped creates tons of waste products. Some waste products are from the mineral ores during excavation, and some are intentionally mixed during extraction and processing.
These contaminants ultimately move to the water present nearby and affect the aqueous ecosystem adversely. However, the amount of toxic chemicals exposed depends on the type of ore mining happening.
Some rocks get crushed during the overburden removal process to expose toxic radioactive chemicals. If not properly maintained, these chemicals could flow and merge with the water of that region.
As per a report, while mining copper ores in Canada, each tonne produces 99 tonnes of waste materials.
After the waste disposal, the water resources present in that area are the go-to source for discarding residue water. This is another reason for water contamination due to mining activities.
Open-pit mining has become more devastating to the environment by affecting our biodiversity. Most of the mining places come under the dense biodiverse area. And that causes us to question our motto for sustainable development. While mining is vital for our economy, the effects of open-pit mining still raise questions about environmental conservation.
Most of the surface mining species go extinct due to mass land degradation. The pollutants produced during the process cause suffocation to the organisms present in that landmass.
Further research has found that open-pit mining has influenced some endangered species substantially. And this is a huge reason to consider sustainable mining practices. Habitat fragmentation is another result of such a type of surface mining.
Poor practices during open-pit mining can create sinkholes and make the environment susceptible to damage. Sinkholes are the cavities formed after the deformation and displacement of the overlying strata. The possible causes of sinkhole formation include weak overburden removal practice, shallow depth extraction, geological disturbances, earthquake, rainfall, etc.
Sinkhole subsidence is one of the leading causes of surface structure (like buildings) damage. It can immensely affect the water flow. Other cavities can affect the vegetation and nearby habitats by releasing harmful chemicals.
The Toxicity Affects the Air
As per the Department of Environment list, some minerals mining causes more damage to the environment than others. And one such devastating effect on the environment by open pit mining is air pollution.
Those minerals include coal, gold, limestone, manganese, iron ore, lead, zinc, copper, pyrite, bauxite, chromite, dolomite, apatite and rock phosphate fireclay, barytes, silica sand, kaolin.
Mineral production from the ores after mining generates an enormous amount of toxic wastes that, after mixing the atmospheric air, causes air pollution.
According to research, suspended particulate matters and respirable particulate matters are pollutant products through open-pit mining. These are more harmful than the emissions from automobiles.
Further, the large amount of fossil fuel burned during extraction causes the environment to pollute. This not only affects mine workers health but also the local atmosphere and flora and fauna of that area.
Deforestation and Vegetation Loss
Nevertheless, to say, open pit mining environmental impact causes deforestation and vegetation loss. Along with removing topsoil rocks, we remove the vegetation in the mining, causing an imbalance in the food chain and food webs.
A report shows that about 44% of mines lie in forest areas full of charming biodiversity. And our work towards enriching the economy impacts the environment directly and indirectly. This further takes us towards the leading cause of species fragmentation, threat, and habitat destruction.
So, these are the devastating impacts or problems with open-pit mining on the environment. Unmeasured mining practices provide more dangerous effects. But with control measures by the government and other authorities, we can reduce the drastic influence of surface mining on our planet. Improvement in technology is one of the leading ways to control the impact.
Also, some higher authorities from various countries are taking other measures to reduce the amount of waste produced. Also, special care is taken to refine the harmful pollutants before exposing them to the environment.
Some other research and studies are also discovering more sustainable ways of mining that have less or little environmental impact.