Constructing soils for climate-smart mining

Surface mining is inherently linked to climate change, but more precise monitoring of carbon dioxide (CO2) emissions is necessary. Here we combined the geolocation of mine sites and carbon stock datasets to show that if all legal active mining sites in Brazil are exploited over the next decades, 2.55 Gt of CO2 equivalent (CO(2)eq) will be emitted due to the loss of vegetation (0.87 Gt CO(2)eq) and soil (1.68 Gt CO(2)eq). To offset these emissions, we propose constructing soils (Technosols) from mine and other wastes for mine reclamation. We show that this strategy could potentially offset up to 60% (1.00 Gt CO(2)eq) of soil-related CO2 emissions. When constructed with suitable parent materials, Technosols can also restore important soil-related ecosystem services while improving waste management. The construction of healthy Technosols stands out as a promising nature-based solution towards carbon-neutral mining and should, therefore, be considered in future environmental policies of major mining countries. Soils constructed from mine waste can help mitigate future mining-related carbon dioxide emissions by as much as 1 Gt CO(2)eq in Brazil through supporting ecosystem carbon stock recovery, suggest estimates derived from geospatial analysis of legal mining activity and soil carbon in Brazil.