Environmental Engineering Reference
In-Depth Information
FIGURE 1.1
Shift in Copper/Ore Production and
Ore Grade over the Last Century
2,500
2.0
1.6
2,000
Modern technologies and equipment
permit excavation at a previously
unknown scale, exploiting mineral
deposits that would have been
uneconomical with past mining
technologies.
Source:
World Bank 2006
1,500
1.2
1,000
0.8
500
0.4
0
0
1930
1945
1960
1975
1988
1991
1994
1997
2000
Copper Production
Ore Production
Copper Ore Grade
than a century ago: mining now occurs at a much larger scale, and much further from
population centres (see Appendix 1.2 for some examples).
The purpose of mining is to excavate from the existing surface down to the mineral
deposit. Modern technologies and equipment allow excavation at a previously unknown
scale, exploiting mineral deposits that would have been uneconomical with past mining tech-
nologies ( Figure 1.1 ). Ore production rates can now reach a staggering 100,000 tons per day
or more, with total excavation (ore plus waste rock) exceeding 500,000 tons per day at the
world's largest mines. As the scale of mining increases, the need for supporting infrastructure
also increases. Today's mining operations may require whole mining towns with associated
infrastructure, including hospitals, air and seaports, power plants, landfill facilities, and roads.
Given the massive scale of today's developments, a project may become the nucleus of
region-wide or even national economic development. The consequences of mining at such
large scale in remote areas, however, are not all favourable. In fact, few industrial endeav-
ours generate more controversy. In the first instance, land clearing for mine access, excava-
tion of ore, particularly in the case of open Pit mines, and provisions for waste rock and
tailings, all change the landscape profoundly. Secondly, there may be community impacts
which are difficult to identify and plan for in advance, including social, economic, and
political changes which potentially affect the opening, operation, and closing of a mine.
It is also true that benefits generated by the mine are almost never equally distributed;
although many profit, large numbers may also lose out as mining processes alter the land-
scape, and disrupt social and economic networks.
The move to larger scale and more remote sites has been accompanied by another chal-
lenge for the mining industry, that is, to contain extraction and processing costs in the face
of declining ore grades. The resulting increase in the volume of processed ore means that
the cost and volume of waste per unit of metal extracted increase, potentially resulting in
greater costs of environmental management as well. To date, these costs have been managed
by technological advances, specifically in the development of larger, more cost-effective bulk
haulage systems.
Given the massive scale of
today's developments, a project
may become the nucleus of
region-wide or even national
economic development.
Mining Terminology
As in any specialized discipline, there are many terms and expressions unique to mining
(for a complete glossary of mining terminology see standard references such as Trush 1968;
 
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