The mining enterprise that is engaged in open-cast mining of the discovered deposit is called a quarry. This method of extraction has several advantages in comparison with underground.
Open cast mining is used in the mining of metal ores, coal, and non-metallic minerals.
An open way to develop deposits achieves more advanced mechanization of work, increasing labor productivity and reducing production costs.
Open pit mining has undeniable hygiene benefits. It is a radical way to prevent the main, occupational diseases of miners – pneumoconiosis and vibration disease – this method of extraction also creates safer working conditions, as a result of which injuries when working in quarries are much lower than in mines.
Over 4/5 of iron ore and mining and chemical raw materials, about 2/3 of non-ferrous metal ores, almost the entire volume of non-metallic minerals and building rocks, more than 1/3 of coal are currently mined in the Russian Federation using an open-pit mining method. moreover, in the near future it is planned to increase the share of opencast mining to 56-60% due to the accelerated development of the Kuznetsk, Ekibazstuzsky, Kansk-Achinsky and other coal basins of Siberia and the Far East.
Open-cast mining in the ore industry is commonly called quarries, in the coal industry – opencasts, and in stone mining – quarries. Most often, the term quarry applies to all types of open-cast mining.
The quarry is a pit, the side surfaces of which are divided into horizontal layers-ledges. The lateral surfaces that limit the quarry are called sides. In modern quarries, the height of the ledges reaches 10 – 15 m. The equipment in the quarries is located on horizontal platforms that provide stability to the sides and serve to move vehicles.
The depth of the quarry is determined by the depth of the mineral and the thickness of the reservoir. In our country, the depth of many quarries is more than 100 m. So, in the iron ore industry, the average depth of quarries is 200 m. The depth of individual quarries reaches 320 m (Sarbaisky, Sokolovsky). The design depth of a number of quarries is 700 – 800 m.