An inventory of UK mineral resources suitable for enhanced rock weathering

Abstract

Enhanced Rock Weathering (ERW), a technology based on amending soils with crushed calcium- and magnesium-rich silicate minerals has substantial CO2 removal potential. Evaluation of the available resources of these minerals and current production capacity is crucial for early-stage deployment of this approach. A robust understanding of the potential limitations in exploiting these resources is also required to ensure the scalability of ERW. This paper provides a spatial inventory of basic silicate rock resources in the UK along with current production capacity and permitted reserves. We also integrate spatial data to assess the potential environmental and social impacts of current rock extraction. 68 active and 100 inactive quarries were identified within outcrops of basic silicate rocks which are mainly distributed in Northern Ireland and in the central belt of Scotland. 14.8 Mt yr−1 of basic silicate rock are estimated to be extracted from which up to 3.7 Mt yr−1 of basic silicate waste fines is estimated to be produced which may be available for ERW in the UK. 490 Mt of permitted reserves is associated with active and inactive queries. Spatial distribution of artificial alkaline minerals including Construction and Demolition Wastes (CDW) and legacy slags in the UK have also been included in the inventory. Transport distances are calculated between all resources and the UK's croplands where these materials may be applied for ERW. The relative appropriateness of the UK's croplands for CDR are also calculated based on their proximity to mineral resources and climate parameters controlling the rate of EW.