If you are a novice to mining, you would be forgiven if you thought that all mining is the same. But no, mining comes in two main forms. Surface mining and Underground mining. Surface mining is a mining process where the rocks and soil overlying the mineral deposits are removed.
It is often the preferred form of mining for most mining companies. This is because removing the terrain surface, or overburden, to access the mineral beneath is often more cost-effective than gouging tunnels and subterranean shafts to access minerals underground.
This method is often considered safer, as well, and doesn’t require extensive electricity rigging and water piping. Surface mining accounts for at least two-thirds of the world’s solid minerals and it is predominantly used to obtain;
- Gravel
- Sand
- Crushed stone
- Phosphates
- Copper
- Iron
- Coal and
- Aluminum
Different Types of Surface Mining
There are various types of surface mining and approaches for each. Learning more about the different types of mining can provide clarity on mining needs and setups. The main types of surface mining includes;
Open-Pit Mining
This is the most common and it is exactly as the name suggests – there’s usually a big hole, or a pit in the ground, which is created by drilling and blasting with explosives. This process is used to mine sand, rock, and gravel.
When open pits are used to mine rocks from the earth, they are called ‘quarries.’
High Wall Mining
This is a combination of sub-surface and surface mining techniques. The idea is that you start off with an open-pit mine and then you drill or bore through the walls in order to extract the resources.
This mining method is performed by a person remotely while in a cabin on the surface and they use a television camera in order to control and monitor the continuous miner machine.
Dredging
This is a surface mining process where the mineral materials from the bottom of the water such as rivers, oceans and lakes are retrieved.
Strip Mining
Strip mining removes a thin strip of overburden, (meaning soil or earth) from the desired deposit, then, the overburden behind the deposit is dumped and the desired deposits extracted. This creates a second and parallel strip in a similar manner and deposits the waste from the second strip onto the first strip, and so on, and so forth…
Mountaintop Removal
Mountain top is an alternative to strip mining. As per the name, this process involves removing the top of a steep mountain, which exposes the deposits desired below. The overburden excavation from the mountaintop is then deposited to the nearby low valley areas, also known as ‘valley fills.’
Surface Mining For Coal Process?
Coal miners make use of extremely large machines to help remove the coal from the earth. Most US coal deposits, known as ‘seams,’ or ‘coal beds,’ are usually near the surface of the earth, but others are found deep underground.
Most modern mining methods allow the coal miners to reach the nation’s coal reserves and produce around three times more coal within an hour.
Methods of Removing Coal
Coal is usually removed using three main methods;
Surface mining – is ideal when the coal is less than 200 feet in the ground. In this case, the large machines will help remove the layers of rock and topsoil which is known as overburden in order to expose the coal seams.
Mountaintop mining – this mining process is a great option for coal mining, and in this case, the tops of mountains are usually removed and dynamited in order to access the specific coal seams. Once the miners are able to remove the coal, they then cover the disturbed area with topsoil in order to plant trees and grass.
Underground mining – is also known as ‘deep mining.’ It is essential for coal as sometimes the mineral can be available hundreds of feet below the surface. Some specific mines are actually thousands of feet in tunnels and could extend out into vertical mine shafts that go on for miles and miles.
Most miners will ride elevators down underground into deep mine shafts and even travel with small trains on long tunnels in order to get to coal. These miners make use of very large machines in order to dig out the coal.
Equipment Used in Surface Mining
The most common equipment you will find used during surface mining includes the following;
A Hydraulic Mining Shovel
The hydraulic mining shovel is used to pick up large amounts of dirt, soil and other materials from the ground and transport them from one point to another for evaluation.
A Wheel Loader
This is a sort of hydraulic mining shovel, but it is different, in terms of size, speed and capacity.
A Mining Crusher
The mining crusher is used for crushing large rocks into smaller ones. It is effective against hard minerals and hard rocks as well.
Motor Grader
This particular equipment is not usually directly involved in the actual surface mining process, and its main function is ensuring that the trucks and excavators are moving swiftly and easily from point A to B.
A Blasthole Drill
The blast hole drill is used when making holes at a mining site where explosives would need to be placed. It is usually powered through electricity, diesel, or hydraulic functionality.
Highwall Miner
A high wall miner is used when mining in open-pit mines for extracting coal. It can be used when the other extraction methods cannot excavate more minerals.
Draglines
Draglines work the same as excavators, and the only difference is that they are used in a much larger scale of operation during mining.
How Can The American Mine Services Company Help?
At the American Mine Services company, our Industrial Generating Contracting Division – AMS Industrial, has been focussing on federal markets, specifically piping, dams and hydropower. We serve the civil and mining construction industries during the design, evaluation, and construction of mines, tunnels, and excavations.
Our AMS mining general contractor services are in high demand, and if you are thinking of starting a mining company, please contact us for the following incredible services:
- Underground Development
- Contract Operations and Training
- Equipment and Facility Installation
- Mine Rehabilitation
- Mine Sealing
- Drill and Blast
- Rock Excavation
- Ground Support
- Tunneling
- Highwall Work
For our mining services, maintenance and projects, contact American Mine Services today.
American Mine Services
130 Miners Drive
Lafayette, Colorado 80026