The Range of Environmental Concerns - Mining and the Environment: From Ore to Metal - page 538

land surfaces generally have greater heat conduction, and more heat storage than the nat-
ural land covers they replaced. Heat energy is also added through the operation of min-
ing equipment and power generation. Finally, evaporation and transpiration from various
natural surfaces act to cool the land surface and local atmosphere. At mine sites, drainage
systems rapidly remove surface water. Thus, little water is available for cooling.
All factors combined, mine areas tend to be warmer than the surrounding areas. As in
urban areas, there is then at least theoretically the potential for locally increased rainfall
due to the combined effect of particulate air pollution and increased convectional uplift
due to increased surface temperature. Particulate air pollution may enhance rainfall by
increasing the number of condensation nuclei. The incremental temperature increase may
add to convection currents over the mine area.

Mine areas tend to be warmer
than the surrounding areas.

Global Climate Change

Mining also contributes to greenhouse gas emissions that are believed to contribute to
global climate change. It is now widely believed that climate change has caused negative
impacts on the global environment and there are many differing predictions about future
impacts. Mining operations typically move, break, and grind large quantities of rock, all
energy-intensive activities. Energy generation at a mine site is almost always based on the
consumption of fossil fuel, releasing carbon dioxide (CO 2 ), a prominent greenhouse gas
(GHG) to the atmosphere. Subsequent mineral processing, especially in the steel industry,
adds to CO 2 emissions. Equally the use of coal as an energy source continues to be a major
contributor to global CO 2 emissions.
On the other hand, the mining industry is not always acknowledged for its con-
tribution to the reduction of vehicular emissions. Mining produces the light weight
metals (aluminium and magnesium) that have enabled manufacturers to produce vehi-
cles which are far more fuel efi cient than their predecessors. Similarly, mining pro-
duces metals such as platinum and palladium which are used in catalytic converters
that also improve combustion efi ciency as well as reducing potentially toxic emissions.
Furthermore, mining produces the materials used in the manufacture of computer chips
and electronic fuel injection systems which have also improved vehicle fuel efi ciency.
The net effect of these technical innovations, all of which depend on products obtained
from mining, is that fuel consumption in the United States has remained essentially the
same over the past decade despite the increased numbers of vehicles and a large increase
in the numbers of large SUVs. This also holds true for Europe and other parts of the
world.
Despite the best attempts of the mining industry to reduce greenhouse gas emissions
(such as minimizing waiting times of mine equipment, reducing rolling resistance, and
optimizing fuel efi ciency), the amounts of greenhouse gases produced per tonne of con-
centrate shipped usually increase over the life of the mine, due to increased haulage dis-
tance, increased vertical transportation distance as the depth of mine pit increases, and
sometimes also increasing stripping ratios as the mine approaches its economic mine life.
Numerous challenges are involved in addressing issues related to mining and climate
change. They include:
●

The amounts of greenhouse
gases produced per tonne of
concentrate shipped usually
increase over the life of the mine.

Developing a Greenhouse Gas Policy;

●

Establishing the carbon footprint;

●

Evaluating the GHG risk proi le ( Case 13.9 );

●

Reporting emissions; and

●

Implementing measures to reduce or offset GHG emissions.