Surface mining is a method of extracting minerals and resources from the Earth’s surface. It is a highly efficient and cost-effective method of mining that has become increasingly popular in recent years. There are five main types of surface mining: strip mining, open-pit mining, mountaintop removal, dredging, and highwall mining. This article will give you a detailed explanation on each type of surface mining.
Strip mining is a method of surface mining that involves removing the surface of the terrain to access the mineral underneath. Miners use this type to extract coal and other minerals near the surface. The process involves using huge machines, such as bucket-wheel excavators, to remove the overburden of soil, rock, and vegetation. There are two types of strip mining, area stripping, and contour mining. Area stripping is used on flat terrain where the overburden is removed in long strips and deposited in the previous strip. Contour mining is used on hilly terrain where the overburden is removed along the contours of the outcrop in smaller, custom-shaped excavations.
Open-pit mining is a surface mining method involving removing ore from an open pit. Miners do not refill the pit after mining and they often convert the pit to a landfill or waste disposal site after extracting the ore. Companies typically employ this type of mining to extract materials used in buildings, such as limestone, granite, and marble. Open-pit mining is efficient and cost-effective, but it can be dangerous to work in and permanently alter the surrounding ecosystem.
Mountaintop removal is a highly controversial surface mining method involving removing the top of a mountain to access the minerals underneath. This method is mainly used for extracting coal and is only practical when the ore is 400 feet or deeper. The process involves using explosives to blast the overburden and then moving the broken mountaintop into valleys and filling below. The major concern with this mining method is permanently altering ecosystems and entire landscapes.
Dredging is a method that is used primarily to extract gold and other precious metals from rivers and other bodies of water. This method involves using floating dredges equipped with conveyor belts and scoops to move up a water table and extract minerals from the sediment.
Highwall Mining extracts coal and other minerals from surface mines. This method involves using a continuous miner to cut horizontally into a coal seam, creating a high wall later mined using various techniques, such as auger mining, that allow mining to occur at depth.