Re-purposing of mine waste tailings for carbon dioxide removal via enhanced rock weathering

Enhanced rock weathering (ERW) is a technique for removing carbon dioxide from the atmosphere based on amending agricultural soils with finely ground calcium-and magnesium-rich silicate minerals [1]. This technique has the potential to remove up to 2 billion tonnes of CO2 from the atmosphere each year and could make a substantial contribution to meeting the Paris Agreement target to keep global temperature rise to <2 C above pre-industrial levels [2].

Each year, mining operations produce hundreds of millions of tonnes of finely ground silicate rocks as waste from the mining process, and these wastes are stored in solid residue facilities (tailings dams). The aim of this project is to determine the effectiveness of mine tailings as a feedstock for ERW through the improvement of local soils for food and other crops, in turn creating a circular economy and offsetting or even eliminating carbon emissions from mine sites.