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

2.3.6 Stockpiling and transport of final product .................................................................... 36
2.3.7 Mine closure and post-operational waste management............................................. 36
2.4 Specific impacts of mining on water resources ....................................................................... 36
2.4.1 Acid mine drainage....................................................................................................... 37
2.4.2 Release of metals ......................................................................................................... 39
2.4.3 Cyanide ......................................................................................................................... 40
2.4.4 Siltation.......................................................................................................................... 40
2.4.5 Water use...................................................................................................................... 40
2.5 Small-scale mining .................................................................................................................... 41
2.5.1 Alluvial gold mining ....................................................................................................... 41
2.5.2 Small-scale chrome mining .......................................................................................... 41
2.5.3 Gemstones and semi-precious stones ........................................................................ 41
2.5.4 Tantalum and tin ........................................................................................................... 42
2.6 Differentiating between direct, indirect and cumulative impacts............................................. 42
2.7 The role and importance of natural weathering processes..................................................... 43
2.8 Legislative requirements for the control and management of impacts attributable to mining
operations in southern Africa.................................................................................................... 44
2.9 Legal and policy frameworks that influence or control mining and
minerals processing activities in Zimbabwe ................................................................................ 48
2.9.1 Introduction.................................................................................................................... 48
2.9.2 Mines and minerals legislation and policy ................................................................... 50
2.9.3 Water and environmental legislation and policy.......................................................... 54
2.9.4 Chamber of Mines Environmental Management Guidelines...................................... 59
2.9.5 Concluding Remarks .................................................................................................... 60
2.10 Principal approaches adopted to minimize and manage environmental impacts arising from
mining operations...................................................................................................................... 61
3. THE ZAMBEZI BASIN ....................................................................................................................... 64
3.1 Introduction............................................................................................................................... 64
3.1.1 Geology, topography and soils .................................................................................... 65
3.1.2 Climatic features ........................................................................................................... 67
3.1.3 Population and land use patterns ................................................................................ 67
3.1.4 Hydrological characteristics, water availability and patterns of
water use ...................................................................................................................... 69
3.1.5 Water management systems and institutions ............................................................. 71
3.1.6 Mining and mineral processing operations within the Zambezi
basin ............................................................................................................................... 74
3.2 The Kazungula sub-catchment................................................................................................ 86
3.3 The Chobe - Linyanti sub-catchment ...................................................................................... 87
3.4 The Luiana sub-catchment ...................................................................................................... 89
3.5 The Cuando sub-catchment .................................................................................................... 91
3.6 The Luanginga sub-catchment................................................................................................ 92
3.7 The Lungue Bungo sub-catchment......................................................................................... 94
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