Gunite - A cement applied by spraying to the roof and sides of a mine passage. The following are some common terms encountered: Active workings - Any place in a mine where miners are normally required to work or travel and which are ventilated and inspected regularly. The remainder may represent coal in pillars or coal which is too thin or inferior to mine or lost in mining. Several promising technologies include: Erichwtl Click to enlarge Coal is mined using giant machines to remove the coal from the ground.
The familiar curves and folds of the landscape, the mountains that have anchored communities for generations, are simply gone. For example, in Roman Britain , the Romans were exploiting most of the major coalfields by the late 2nd century AD. Coal power in China. Mountaintop removal, which is used increasingly in Appalachia, became possible only after technology evolved and the economics of mining changed to allow greater stripping ratios.
In , a subsidy was introduced Kohlepfennig. Normally, the gravel and filth from mining is permanently dumped on the land surrounding the mines. Watch the Did-You-Know slideshow. The Middle Coal Measures was the most important with its wide distribution, great number of coal beds and extensive potential reserves. The overburden is then removed, using large earth-moving equipment, such as draglines , shovel and trucks, excavator and trucks, or bucket-wheels and conveyors.
Formation — Any assemblage of rocks which have some character in common, whether of origin, age, or composition. According to a report in the journal Science , mountaintop mining has caused numerous environmental problems which mitigation practices have not successfully addressed. Glossary of Mining Terms. The University of North Carolina Press. A haul road is usually situated at the side of the pit, forming a ramp up which trucks can drive, carrying ore and waste rock. After coal is removed, it typically goes on a conveyor belt to a preparation plant that is located at the mining site. Extraction - The process of mining and removal of cal or ore from a mine.