Open pit excavation
Introduction
It is known as open pit mining, pit mining or open pit or quarry, those mining operations or mining operations "Mine (mining)"), which are developed on the surface of the land, unlike underground or drilling mines. Open pit mining is applied when commercially useful deposits are found near the surface. Mechanical or explosive means are used to remove the soil that covers or surrounds the geological formation that forms the deposit, or material bank. These materials are generically called sterile, while the formation to be exploited is called mineral. The excavated waste must be stacked in waste dumps outside the final area that the exploitation will occupy, with a view to its use in the restoration of the mine.
Before starting any material extraction project, compliance with regulations in various matters must be reviewed and considered: fiscal, labor, health and social security, also carrying out, if required, the Environmental Impact study, and presenting it for evaluation to the state and federal authorities in matters of ecology and the environment, who will be in charge of establishing restoration, recovery, sustainment and maintenance measures to cushion the environmental impact of the extractive activity.[2].
Open pit mines are economically profitable when deposits appear on the surface, are close to the surface, with little cover, or the terrain is not structurally suitable for underground work (as is the case with sand or gravel). When the depth of the deposit increases, the economic advantage of open pit decreases in favor of exploitation through underground mining.
Types of mines
Contenido
Los principales tipos de minas a cielo abierto son:.
Quarries
Quarries are open pit mines, generally small in size, that exploit materials that do not require subsequent concentration, but, at most, crushing or classification by size. The materials obtained in quarries are aggregates "Arid (mining)"), industrial rocks and ornamental rocks.[3].