Environmental Assessment of Natural Coarse Aggregate Production in Gravel Pits—Assessing CO2 Offsets Through Vine Cultivation

Abstract

Featured Application: This research defines a new possibility for mitigating CO2 emissions derived from the production of natural aggregates, particularly in the Autonomous Community of La Rioja, Spain. Natural aggregates are widely used in the construction sector. Their production and generation entail environmental impacts, which must be identified and reduced as far as possible in order for the construction sector to achieve sustainability. The objective of this research is the environmental characterization, through the Life Cycle Assessment methodology, of the production of 1 ton of natural coarse aggregate produced in a common gravel pit in Spain, with a cradle-to-gate scope. The activity data are collected from inventory databases from national companies. Their results reveal emissions of 4.30 kg CO2 eq, the consumption of 106.08 MJ of fossil fuels and the use of 12.52 m3 of natural water per ton of natural coarse aggregate. Subsequently, innovative concepts are explored to mitigate the previously defined environmental impacts through the creation of vine cultivation. The most relevant results indicate that 1 hectare of vine cultivation generates a net balance of emissions of −3.785 tCO2, acting as a carbon sink, which means producing a total of 879.6 t of natural coarse aggregates produced in gravel pits free of CO2 emissions. By applying this cultivation to the construction sector, the aim is to make companies in the sector aware that by adopting this measure, at least in the global warming impact category, environmental impacts can be mitigated and thus contribute to achieving greater sustainability in the sector.