Mine tailings are waste obtained after processing mineral ore to acquire element(s) of interest. They are a mixture of ground rocks with process effluents. The largest water sink at most mines is the tailing storage facility and inappropriate management of water content in mine tailings can become a threat to its stability, and consequently, its environmental safety. Also, for reasons pertaining to water scarcity, water reuse and recycling is a plausible option to mining companies.

Proper handling of mine tailings and water supply management can considerably improve the water-energy nexus. In this article, we evaluate the water-energy nexus in copper mining companies using a water reduction model focused on mine tailing facilities and water supply to the mine site to find the trade-offs between water and energy. To find out about the economic outcomes of the options covered by the analysis, project valuation techniques with a real options approach are used. This approach deploys Monte Carlo simulation to perform sensitivity and uncertainty analysis to evaluate every cost component of each water management strategy.

The results show that where seawater is supplied to the mine site, improving the reuse of water by using dewatering technologies will improve the water-energy nexus. Even though the costs of these technologies are elevated in comparison to traditional disposal method because they are energy-intensive, the reduction of water requirements in the mine will reduce the cost of its treatment and transport which accounts for a large proportion of the total cost.