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

SO4 3.5 4.2 3.8
F 0.05 0.12 0.11
Si 5.03 6.94 4.81
NH4-N 0.05 0.05 0.07
NO3-N 0.14 0.40 0.08
PO4-P 0.011 0.017 0.016
These water quality data (Table 4.26) indicate that water quality in both the Mutale and Levuvhu rivers is
relatively good, though that of the Levuvhu River can be considered to be marginally poorer. This is a reflection
of the intensive and extensive patterns of land use along the banks of the Levuvhu River.
4.22.6 Implications for water quality and quantity management
The available evidence suggests that the very limited mining activities in this sub-catchment are unlikely to have
had any significant impact on either the local water resources or on water quality in the area. Any impact would
be likely to consist of a minor increase in suspended solids concentrations during periods of high flow and,
possibly, minor acid mine drainage with lower pH values and higher dissolved salts concentrations from the
Tshikondeni Colliery.
4.23 Summary of impacts of mining operations on water resources and water quality in the
Limpopo basin
The wide variety of mining operations and mineral processing activities located within the Limpopo basin have
differing degrees of impact on both the water resources available to other users and on the water quality of
these resources. From the available data, it seems clear that those mining operations that are located within
low rainfall regions of the basin (where physical weathering processes predominate) have relatively low and/or
localized impacts on the water resources. In contrast, mining operations located in the wetter regions of the
basin where chemical weathering processes predominate tend to have far more extensive impacts. This seems
to be due to the presence of ample moisture within the soil profile that enables continual chemical changes to
take place and allows the water available to mobilize and transport the different contaminants that become
available.
A summarized overview of the actual and anticipated impacts of mining operations and mineral processing
plants in each sub-catchment of the Limpopo basin is given in Table 4.27. This information provides a useful
impression that could be used to focus water resource management plans and water quality management plans
in the different component areas of the Limpopo basin.
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