Mining is the process employed to extract valuable resources from the Earth. It is done to obtain any resource that cannot be grown or fabricated through artificial means. Mining extracts non-renewable resources like fossil fuels, minerals, and even water
Fremont, CA: There are four main methods of mining: underground, surface, placer, and in situ. The mining method depends on the resource being focused for extraction, the deposit's location below or on the Earth's surface, and the capacity of each method to fruitfully extract the resource. Each mining procedure also has differing degrees of safety and impacts on the surrounding environment, which concerns legitimate mining operations.
Each of the four mining methods is described below.
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Underground Mining
Relatively costly and often used to get to deeper deposits, underground mining involves digging into the Earth and creating tunnels and shafts that attain the deposits of resources. Ore and other resources can be brought to the surface for processing, while waste rock can be eliminated for disposal.
Various types of underground mining are categorized based on the kind of shafts utilized, the technique of extraction, and the process utilized to get to a deposit. For instance, drift mining involves horizontal tunnels, while slope mining employs diagonal shafts to access deposits.
The underground mining technique used is generally based on the area's geology. Specifically, the amount of ground support needed to make mining safe.
Surface Mining
Surface mining involves the removal of plant life, soil, and potentially bedrock to be able to access resource deposits. It is generally used for fairly shallow, non-precious deposits. The two foremost kinds of surface mining are open-pit mining and strip mining.
Open pit mining includes digging out rocks to form an open pit or borrow pit, from which resources are extracted. An open pit mine usually has stepped sides to minimize the risks associated with collapse and a large ramp for mining equipment. In addition, a water management system is generally necessary to keep an active mine from turning into a lake. Open-pit mines are typically worked until the mineral deposit is depleted or different factors make the mine non-profitable. When this happens, the open pit is often modified to turn into a landfill for solid wastes.
Strip mining is mostly utilized to extract shallow, "bedded" deposits, where a mineral layer is screened by a layer of soft topsoil & weathered rocks. Earth's relatively soft top layer is stripped by either a dragline or industrial shovel to uncover a deposit.
Placer Mining
Placers are normally formed by weathering via water and/or wind action, Which are unconsolidated deposits of resources. Placer mining is usually done in riverbeds, sands, or other sedimentary environments and includes sifting valuable materials from sediments. Notably, "panning for gold" can be part of placer mining. The extorted sedimentary material is rinsed and sluiced in placer operations to pull out the desired minerals.
Apart from gold, gemstones, platinum, tin, and other materials can be removed via place mining. For example, at least 50 % of the world's titanium comes from this mining operation.
In-Situ Mining
Also mentioned as solution mining, in-situ mining does not involve removing intact ore beneath the Earth's surface. Rather, it involves pumping chemicals underground to dissolve resource-comprising ore and then pumping what is known as the "pregnant solution" support to the surface, where it can be processed to retrieve minerals. This technique is mostly used in uranium mining.
This technique causes little disturbance to the surface and does not produce great amounts of waste rock. However, to employ this technique, the ore body must be permeable to the extraction liquids, and it must be likely to complete the process without the significant risk of contaminating nearby groundwater.
