The mining industry today is faced with a host of challenges. These include complexities of managing water resources and pressures to operate with increased efficiency and sustainability, all while cost-effectively meeting environmental regulations.
Water plays a critical role in mining – for minerals processing and potable water uses, and for how it affects a mine’s license to operate due to wastewater discharge conditions. Having either excessive or inadequate water can risk mining operations, at times halting operations completely.
As a result, water must be managed at every stage of the mine life cycle – from exploration, to project planning and design, mining and minerals processing, rehabilitation, and to the closure and post-closure of the mine site.
Across the globe, the use and discharge of water by mines is highly regulated. Such regulations are mine-specific and highly dependent on the local conditions of each mine site.
Authorities take into consideration the geographical location of the site, local environmental conditions, processes used, and the mine water balance when issuing and reviewing mine operating licenses.
Consequently, it is vital for mining companies to juggle the delicate water balance issue while keeping in compliance with regulations around water use within mines. Mining operations require not only the right solutions to manage water sources for the mine, but also how water is used and discharged thereafter.
For some mines, local conditions prompted the enforcement of a strict zero liquid discharge (ZLD) requirement – where no excess water from the mine may be released to the local environment – in a bid to minimise environmental impact.
In such cases, mines have turned to water management solutions to reclaim wastewater for reuse in mining processes. Such solutions enable operators to reduce wastewater volumes while curtailing the need for fresh water. For some mines with a negative water balance, this can also be an effective solution to reduce reliance on external water sources for their mining operations.
To meet ZLD requirements, mines are required to convert wastewater into a solid. Evaporation is a common method adopted by mining operators as an approach to achieve ZLD. This usually involves the construction of solar evaporation ponds or the use of mechanical and thermal evaporation technologies.
In fact, the application of evaporation methods can be more efficient and practical than trucking wastewater offsite.
Additional benefits like the minimisation of environmental impact and cost savings – from reduced expenses on transportation of waste and reuse of water – also make the evaporation approach a choice worth considering.
In some places with strict discharge regulations, leaving untreated mine water to seep into the ground or flow into nearby water streams is prohibited. To minimise the impact on the environment, mine water must be treated for turbidity, pH, TDS, and removal of heavy metals.
Mining operators have the responsibility to ensure that the stipulated water quality is achieved before the mine water is released to the local environment off the mine site.
Responsible management of water by mining companies is a key ingredient for ensuring that their contribution to sustainable development is positive over the long term.
When it comes to addressing regulations and compliance issues, it is important to work with a trusted partner with the right expertise and the capabilities to provide both the ‘hardware’ (technology) and ‘software’ (experience) required for water management success.
With a keen understanding of the unique requirements of mine operations and with strong expertise in the management of mine water issues and risks, Veolia offers mine operators specialised water treatment solutions that address compliance with process and environmental requirements – meeting the most demanding standards of reliability, safety and quality – while achieving long-term cost-effectiveness.