basic condition to extract coal via open pit mining in gambia

Jan 23 2017 · Ore is mineralized rock containing a valued metal such as gold or copper or other mineral substance such as coal Openpit mining involves the excavation of large quantities of waste rock material not containing the target mineral in order to extract the desired mineral ore

In openpit mining waste is transported to a disposal site and the ore is transported to a downstream processing site This method commonly involves a sequence of benches from the surface to the deposit As the open pit goes deeper into the ground all of the benches above are extended outward

Dec 22 2012 · Surface Mining If coal is less than 61 meters 200 feet underground it can be extracted through surface mining In surface mining workers simply remove any overlying sediment vegetation and rock called overburden Economically surface mining is a cheaper option for extracting coal than underground mining About two and a half times as much coal can be extracted

Although the basic concept of an open pit is quite simple The typical large open pit mining operation that has been in production for 10 years and more is Coalmine 2

54 OpenPit Mining 541 Market Estimates Forecast 20172023 542 Market Estimates Forecast by Region 20172023 6 Global Surface Mining Market By Application 61 Introduction 62 Coal Mining 621 Market Estimates Forecast 20172023 622 Market Estimates Forecast by Region 20172023 63 Coal Mining

Surface mining is a form of mining in which the soil and the rock covering the mineral deposits are removed It is the other way of underground mining in which the overlying rock is left behind and the required mineral deposits are removed through shafts or tunnels Surface mining is basically employed when deposits of commercially viable minerals or rock are found closer to the surface

Mining Mining Underground mining When any ore body lies a considerable distance below the surface the amount of waste that has to be removed in order to uncover the ore through surface mining becomes prohibitive and underground techniques must be considered Counting against underground mining are the costs which for each ton of material mined are much higher underground than on the

Dec 21 2015 · Blasting equipment is used for both underground and open pit mining operations and is known to be one of the most hazardous aspects of the job For mining operations to be successful good blast designs are absolutely vital as poor practices and excessive explosives can result in damage to rock structures causing unwanted caving

2 Open pit mining Excavating a giant hole in the landscape to remove widely spread mineral deposits 3 Placer mining Sifting through sand and silt in riverbeds for minerals using a sluice with running water 4 Subsurface mining Tunneling deep underground to extract minerals 5 Strip mining

4 Tunneling deep underground to extract minerals 5 Surface layers are removed to expose and extract horizontal mineral deposits 6 Restoration of mined areas to premining conditions 7 Dissolves and extracts resources via a narrow borehole