Dom Triviamaster

The Process of Open Pit Mining: Structure and Procedures

There are several forms of mining that are used to extract minerals and rocks from layers of earth and open-pit mining is one of these methods. This method uses a borrow or open pit and is most frequently used in situations where the desired rocks or minerals are located close to the earth’s surface.

There are several forms of mining that are used to extract minerals and rocks from layers of earth and open-pit mining is one of these methods. This method uses a borrow or open pit and is most frequently used in situations where the desired rocks or minerals are located close to the earth’s surface.

The Structure of the Open-Pit Mine

An open-pit mine is structured in steps, often also termed “benches,” which are the pit’s vertical levels. These steps commonly range from four to sixty meters, but the size is largely dependent upon the machinery used by the mining company. The walls of the pit are called the batter, while the flat portion is called the berm or the bench.

Open-pit walls will generally be dug in a manner that minimizes any danger of rock falls or landslides in the event of poor weather conditions such as heavy rain. However, there may also be supports such as rock bolts or shotcrete used to stabilize the area for workers. In addition, many open-pit mines require water relief measures to be put in place. In some instances, bore holes may be drilled into the wall, which can also cause wall failures.

Hauling Rocks and Minerals from an Open-Pit Mine

All mines have to have a way to haul out the ore that is mined. Most open-pit mines have a roadbuilt at the pit’s side specifically for hauling away the ore, as well as any waste rock. This roadallows trucks to move safely beside the mining area and obtain their respective loads.

The waste is also an issue that has to be dealt with accordingly in any mining situation. In mostcases, waste rock will be placed in a waste dump, often an area close to the pit’s edge that is alsostepped in structure.

What is Left Behind by Open-Pit Mines?

Tailings are a telltale sign of a former mining operation. Tailings are the leftovers of ore that was processed and, if fresh, it is often found in slurry form in a settling pond or what is called a tailings dam. The water eventually evaporates and, if left unattended, may pose a hazard to wildlife and humans alike. Tailings may have high levels of toxicity because there are often sulfide minerals present in them, along with cyanide and other chemicals used in the extraction of ores and minerals.

The Commonality of Open Pit Mines and Their Fate

Most people refer to open-pit mines as quarries, so they are a great deal more common than onemight otherwise realize. In most areas that they exist, open pit mines are often repeatedlyenlarged to the point that the resource has been exhausted or until the mining process is nolonger economically feasible.

Once an open-pit mine is closed, there are several scenarios that may occur. Reclamation andrestoration has been a more recent issue, meaning that some companies that own open-pit minesmust take measures to restore the land prior to leaving the site. Other areas convert these miningareas into landfills, lakes or other ventures.

To find out more about open pit mining and other, general mining topics, please visit PublicMining.org, a free resource directory showcasing public mining companies like Cream Minerals, Crazy Horse Resources and thousands more.

Source: Free Articles from ArticlesFactory.com

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