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

6.1.8 “Peripheral” or indirect impacts linked to mining
The pivotal nature of mining activities in the general development of southern Africa means that they inevitably
have had several “peripheral” or indirect impacts on the biophysical environment. A few specific examples are
highlighted here to sketch the scope of the concerns:
• The influx of miners and their families and dependents into existing and new mining areas is often
accompanied by the development of informal and unserviced settlements. In turn, these are characterized
by poor or inadequate sanitation systems with the result that nearby watercourses become contaminated
with sewage and domestic garbage. This can be clearly seen in several areas of the Zambian Copperbelt
(See Figure 3.15) in the Kafue sub-catchment of the Zambezi basin, as well as the platinum and chrome
mines of the Crocodile sub-catchment in the Limpopo basin and the Witbank and Highveld coalfields in the
Olifants basin of South Africa.
• Settlements that develop in the peripheral areas of mining operations often rely on subsistence agriculture
for their livelihoods. This results in progressive de-vegetation of the areas around such mines as trees are
cleared for fuel wood and to open up areas for cultivation. Good examples of this can be seen around many
towns on the Zambian Copperbelt (See Figure 3.15). In extreme cases, the subsistence agriculture may
extend into local wetlands or ‘dambos’, thereby reducing their ability to attenuate stream flows and prevent
flooding.
• Increased population numbers places greater pressure on every natural resource in an area. This pressure
varies from demands for fuel and water, housing and construction materials, to accelerated exposure of the
catchment surface to erosion processes. Singly, many of these effects may well be non-significant.
However, when they occur simultaneously, their significance may increase by orders of magnitude. Once
again, these “cumulative effects” are clearly visible on the Zambian Copperbelt.
• The construction of the Kariba Dam to provide an assured source of hydroelectric power (principally for the
Zambian Copperbelt, but also for cities and towns in Zimbabwe) had a number of “unanticipated” or
“peripheral” effects. Whilst the most noticeable of these was probably the dramatic rescue of thousands of
animals from newly flooded areas and the explosive spread of Kariba Weed on the newly formed lake, some
55,000 people had to be resettled from the flood basin. This had a sequence of profound social and
economic consequences that had not been anticipated and the process has helped to fuel the growing
debate on the relative costs and benefits associated with the construction of large dams.
6.2 Current management approaches to prevent, minimize and abate impacts
caused by mining operations
Over the years, increasing consciousness of the need to minimize impacts on the biophysical environment has
driven considerable international and local debate around the impacts of mining and mineral processing
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