The challenges of estimating the water footprint of mined commodities
Year: 2015
Type: conference-paper
Abstract: The concept of a ‘water footprint’ has gradually developed over the past decade as an extension to the ‘virtual’ or ‘embodied water’ concept. A ‘water footprint’ estimate attempts to quantify the environmental impacts that arise from the use of water during the manufacture, use or disposal of a product or service. Methodologies for estimating water footprints have been evolving to account for factors such as changes to water quality and the relative scarcity of water in different regions. Recently an international standard for water footprinting (ISO 14046) was developed to provide an over-arching framework for how studies should be conducted and presented. Despite this progress there are still challenges to address to improve the methodology underpinning water footprinting studies, particularly when applied to mined products. As an example, mines are often transient in nature. The production only lasts a decade or few decades before the closure, rehabilitation or abandonment of the mine occurs. Following open cut mining, pit lakes sometimes form, leading to permanent drawdown of the surrounding groundwater levels. Current methodology provides little guidance on how to account for long-term hydrological and water quality impacts that occur after mine closure, when assessing the water footprint of a mined product. Addressing these types of methodological issues will enable competing mineral processing technologies, individual mines and commodities to be fairly and consistently benchmarked against each other on the basis of their impact to water resources. Key areas that need to be improved for future water footprint estimates of mined commodities include: the spatial resolution of water consumption and availability data, understanding how to model and incorporate long-term changes in hydrology and water quality, and developing consistent geographical and temporal boundaries of assessments.
Authors: Stephen Northey, Gavin M. Mudd, Nawshad Haque
Language: English
Subfield: Environmental Engineering
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2548704901