Environmental impact of a rock quarry

Rock quarries occupy large areas of land and thus they affect the environment considerably and in various ways. The main inputs are different forms of energy; explosives for blasting, electricity and fuels to power heavy plant machinery, trucks, equipment and generators.1 The electricity consumed will obviously generate emissions and waste at the power stations whilst fuels used at the quarry will generate gaseous emissions on site.

The processes and extraction methods employed generate noise, mainly due to the blasting or excavation equipment, transport and crushing. This may cause a nuisance to nearby residential, commercial or industrial buildings and thus disrupts the physical environment. Mitigation measures can be adopted to minimise the noise produced. These include the installation of linings and claddings, surfacing of internal roads, use of silencers on engines and use of conveyors. Propagation of noise can be reduced by acoustic screens in the form of natural land formations or mounds. It is also important to maintain certain minimum distances from residential areas.

When blasting is used for rock extraction, besides the noise, there is also vibration in the ground and pressure waves in the air as well as the possibility of pieces of rock flying off for considerable distances. The pressure waves may be strong enough to break or damage weak structures. To minimise the effects of blasting one can keep the amount of explosive used as low as possible, detonate blast holes individually and ensure a safe distance from other personnel or property. Ground vibration is not only caused by blasting but also by other plant equipment and machinery. This may affect sensitive structures situated close to the quarry. Pieces of ro...

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...s, historic artefacts, ancient buildings and stalactite/stalagmite caves.

The disposal of quarry waste may also have an effect on the environment if it is not carried out in an organised and well planned manner. This material can be used for reclamation of other areas such as disused quarries or derelict land or within the quarry itself, subject to the necessary permits and conditions laid down by the authorities. It must be ensured that the disposal of quarry waste should not cause a negative visual impact or pose a threat to surface and groundwater and should avoid environmentally sensitive areas. Finally there must be an effective restoration strategy so that disused quarries are not left as a large gaping hole in the ground but they are rehabilitated for reuse as nature conservation, public spaces, recreation, agriculture, forestry or other developments.