Surface Mining

There is an increasing demand for energy and raw material in today’s industrialized world. One mining method that aims to extract energy and raw material sources located naturally in the earth's crust is the “surface mining” method.

Surface mining is generally performed by excavating waste material (overburden stripping) located at the top of the ore reserve following a blasting operation if required and then producing the ore material.

An overburden stripping operation that involves waste material excavation, loading, and hauling activities must be performed to achieve access to ore reserve.



Bucket-wheel excavator systems, shovel-truck excavation systems, or combined systems are utilized in surface mines.

70% of the mining activities worldwide is performed by surface mining method.

There are various advantages and disadvantages of the surface mining method compared to underground mining. It requires a high capital investment in the initial years of operations, may lead to environmental problems, needs waste dumping areas, and is affected by climate conditions. On the other hand, it offers many advantages such as higher mining recovery, lower operating cost, safer working conditions, and recovery of orebody even with thin layer thickness without leaving any pillar.

Surface mines can make ore production at more profound elevations day by day due to developing technologies and mining machinery.

To implement the overburden stripping operations efficiently and adequately, projects should consider the safe bench angle, bench height, and bench width parameters determined according to the mining areas' geological conditions and rock mass characteristics.

Production volume calculations are carried out in surface mines by determining the volumetric difference between before and after excavation. With the developing technology, these measurements can be performed using unmanned air vehicles (drones).

Surface mines are structured with benches advancing from top to bottom, and this advance creates a production area generally shaped like a reverse cone. Bench angles should be determined in such a way that bench slopes should resist the gravitational force. A proper bench geometry and durable rock formation will help the mines to be operated in a safe working environment.

Using steeper slopes in this mining method will reduce overburden stripping amount, unit production cost, and waste dump area requirement, resulting in less deterioration in the natural topography.

The stripping ratio is the volume of waste material to be removed for one unit of ore production. It is generally valued in terms of m³/m³, m³/tonne, or ratio between waste thickness and ore thickness. Since production cost is defined in terms of tonne, the stripping ratio is commonly valued in m³/tonne.

If feasibility studies, which are completed after detailed exploration programs, point to that coal reserves in TKI’s license areas can be extracted with surface mining method, the related operations are carried out either by TKI’s own means, subcontractors or with royalty procedures, using proper surface mining machinery and equipment. These operations are performed proactively considering environmental and occupational health and safety precautions regarding the security of supply, national needs, and profit/loss balance.