Environment Protection Measures which may be carried out during and
after mining.
1. Dust control measures
 Collect water which falls in rainy season in sumps
(a) prevents muddy run-off from mine
(b) provides water store which can be used to spray over haul
roads.
 Haul roads can be surfaced with laterite to stabilise them - so less
dust created by trucks travelling over them or transporting the rock.
 Re-vegetation of landscape - helps to reduce dust pollution from
workings.
 Use collection system at the crushing plant to suck in dust (with
powerful extractors) and mix it with water so that little can escape
into the air
 Site crushing plants in narrow valleys - to cut down pollution
 Use dust monitoring equipment.
2. Noise control measures
 Site crushing and processing plants in narrow valleys - to reduce
amount of noise pollution.
 Use noise monitoring equipment
 Re-vegetation of landscape - helps to reduce noise pollution (and
also screens the mine workings from nearby villages/towns).
Injection of fertilisers into soil helps to speed up growth of
vegetation.
3. Extraction control measures.
 Use most efficient extraction methods so ores can be removed from
lower grade tailings (waste material from mine)
e.g. pass tailings through activated carbon to remove tiny gold
particles
e.g. use acid mine drainage - allow it to percolate through waste
rock so it washes out traces of copper.
4. Water control measures
 Test water in tailings pits, pump back into mine and re-use in the
extraction process. (Particularly important if cyanide residues have
been left in tailings after the extraction process).
 Filter and return water into nearby streams (after it has been used
for extraction) only if it is free from solids and dissolved
contaminants.
5. Acid mine drainage control measures
Stock pile of disturbed rock
containing sulphur left after mining
S
S
S
S
S
Drainage of water from mine tips
Acid conditions develop when rock
material is exposed to the air –
because sulphur oxidises & dissolves
in water forming sulphates &
dissolved metals*
*These may be harmful to people &
the environment



Potential for pollution by acid mine drainage is greatest if tailings are
close to the river drainage system.
Following steps can be taken:
(a) leave solid rock pillars to separate the mine from the river
(b) ensure mine is lower than the river so seepage is towards the mine
(c) treat water in contact with mine material containing >1% S before it
is released (neutralise acids, remove solids)
(d) monitor water content on release.
Reduce loss of water into the aquifer by:
(a) building deep cut off walls into the bedrock (ensuring walls are
impervious)
(b) placing sumps behind cut off walls where acid water can be
pumped, treated and re-circulated into the processing plant.
6. Smelting control measures


Place smelters some distance away from the mine and/or town
Reduce SO2 and dust emissions by ensuring best technology used so
very few gases released into the atmosphere.
7. Environmental control measures

Remove soils contaminated by lead in mining waste and replace with
new top soil re-seeded with “native” grass and flowers to ensure
diversity of species after mining completed.
 Fill in pits and re-landscaped sites to recreate original features (e.g.
wet land areas) after mining completed.
 Carry out environmental impact reports* before mining starts. These
should then be carried out again at each stage of mining i.e.
1. Development stage
2. Operational stage
3. Rehabilitation stage
*Reports consider costs, laws of land, company policies and the effects on
vegetation, wildlife, climate, air quality, noise and ground water.