SRK has had extensive experience working on mine water management projects in Middle Eastern countries, particularly in Saudi Arabia. The climate in this part of the world is mostly arid with very limited rainfall, runoff and recharge. It follows that one of the major challenges mines face is guaranteeing a sustainable long-term supply of water for the mine operation.
While there are some very extensive sandstone and limestone aquifers in the Middle East, which are particularly evident in the northern and eastern sides of Saudi Arabia, these sources have become severely depleted over recent decades as demand has vastly outstripped natural replenishment by recharge. With the exception of the phosphate and bauxite operations in the north of Saudi Arabia, most mining projects in the Kingdom are in the Arabian Shield on the western side of the country, at a considerable distance from any of the higher yielding sedimentary aquifers. For most mines located in the Shield, local wadi sediments and fractures in the crystalline bedrock provide the only sources of water; however, these scarce resources are also used by the Bedouin and local settlements and, therefore, are highly sensitive. Clearly, water for potable use by the local population invariably takes precedence over any planned industrial use.
Finding solutions to the scarcity of surface and groundwater resources and to strategic issues, such as local competition for the same resource, often requires an unconventional approach and considerable lateral thought. SRK has found that in this environment, it is especially important for the operator to tailor the mine production and processing to match the available resource and factor in any expansion programs at a very early stage to ensure that future water sources are reserved before being taken for other developments. Where the project requires more water than is available locally, then careful consideration must be given to improving management practices, to minimising wastage through paste technology, recycling water in the mine circuit, using advanced technologies like reverse osmosis, or the use of alternative supplies. For example, alternatives include piping water from more distant catchments, the sea, or by using grey water from nearby urban centres. Some of these solutions are expensive, so have to be considered within the framework of an overall cost-risk-benefit assessment. In some cases, it may be necessary to set up alliances with other mines, industries or local government to introduce economies of scale where water use would otherwise be prohibitively expensive.
SRK advises mining companies to consider assessing potential water resources at a very early stage, using all possible options to ensure that potential mine development is optimised to those available resources and not based on unrealistic expectations.
