Decribe 2 ways in which deep mining is different from opencast mining
Answers
Generally, mining projects can be categorized into two different sectors: open plan and underground mining. Although the location of ore deposits ultimately determine which mining method will be most effective, mine project management also determine whether excavation costs won’t exceed profits when considering how deep the project will run.
As mining below 2km incur excavation costs that often exceed profits, open pit mining can be considerably less expensive. Mining consultants in South Africa provide mining solutions that help determine the most efficient course of action.
These two vastly different mining methods employ different machinery, processes and strategies and carry different consequences:
Open pit mining
This mining method employs bulldozers and other earthmoving machinery to strip soil covering shallow veins of ore deposits. Ore, dirt and other debris is moved out of the mining area, or pit, with large mine trucks, making room for further excavation. Once the project has run its course and profitable ore deposits have been depleted, the area is filled in with earth again. Reclamation work to restore the surface is gone about in different ways:
First, an environmental impact assessment is made.
Rehabilitation projects are then put in motion, aimed at restoring forestlands, flora and fauna.
Finally, follow-up reports are compiled, assessing whether the landscape’s ecology is returning to normal.
Underground mining
What makes underground mining so expensive is getting valuable ore back to the surface, whether through a horizontal or vertical excavation passage. Compared to open pit mining, which often mines soil, gravel, and inexpensive ores, underground mining is targeted at more valuable ore deposits. This mining method does, however, become considerably less profitable the deeper the ore deposits are located.
Another downside of underground mining is the danger labourers who work underground are exposed to. Radiation (from naturally-occurring radioactive materials) is a health risk all underground personnel face, as oxygen circulates the underground passages with difficulty.
Most radon gas atoms are directed to the surface if ventilation processes are fully functional. The intricate layout of underground passages do, however, increase the risk for pockets of gas remaining underground, endangering mine workers in the area. Mining engineering consultants can provide aid in curbing this problem and ensuring that mining will be done as safely as possible.