OVERVIEW OF THE IMPACT OF MINING ON THE ... - IIED pubs

management • Reseeding/planting
disturbed areas
of
• Re-contouring
walls/waste dumps
pit
• Water quality treatment
• Fencing dangerous areas
• Monitoring of seepage
2.3.1 Exploration and surveying activities
mines
• Acid rock drainage from exposed ores
• Continuing discharge of contaminants to
ground and surface water via seepage
• Fauna and flora habitat loss and
disturbance
• Windborne dust, including radionuclides
• Dangerous areas that pose health risks
and possible loss of life (e.g. shafts, pits,
etc.)
Most of the potential environmental impacts associated with mining exploration and surveying activities occur at
a very much smaller scale than those recorded during mine operational activities, and are mainly restricted to
specific exploration areas and sites or slightly larger localities. However, the cumulative effects of exploration
activities at multiple sites within an area have the potential to drive environmental change, particularly from a
larger regional perspective (Table 2.2).
The more common and noticeable effects of these cumulative impacts include changes in aquatic and terrestrial
ecosystem health. The general environmental impacts of mining exploration include the removal of vegetation
for survey lines, vegetation damage and soil erosion from vehicle tracks, abandoned equipment and supplies,
soil, vegetation and water resource pollution and contamination.
Mining exploration impacts include local spillage and leakage of fuels, oils and drilling fluids resulting in site and
vegetation contamination. Potential surface water pollution may result from wastewater discharges, sewage
disposal and waste rock dump heavy metal and sediment drainage. Habitat disturbance and soil erosion
impacts are caused by vegetation clearing for access routes and drilling sites, and the use of bulldozers for
stripping overburden to examine the underlying bedrock.
2.3.2 Mine development and start-up
The development and start-up of a mining operation covers the period of time when considerable changes take
place as the mine infrastructure, plant and facilities are constructed, and when the ore body is first exposed (see
Table 2.2). In practical terms, the scale and sequence of events varies from mine to mine, but always entails
dramatic changes to most features of the local environment. Large areas of land are cleared of vegetation and
leveled prior to construction, whilst testing of ore processing and refining facilities is finalized. The spatial scale
of the mine site where impacts may be displayed can vary from a few tens of hectares to several square
kilometres. The most immediate impacts are seen as disruptions and disturbances to plant and animal
communities, accompanied by loss of aesthetic value and appeal.
During the development and start-up phase of mining, exposure of rocks, ores and soils to rainfall and winds
leads to relatively high levels of atmospheric contamination by dusts and water contamination by eroded and
oxidized materials, accompanied by increased erosion of the site and sedimentation of local water courses.
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