Geologic sequestration of carbon dioxide, also known as carbon capture and storage (CCS), is one strategy to reduce the emission of greenhouse gases generated through the combustion of fossil fuels. Geologic sequestration of CO2 involves the injection of supercritical CO2 into underground brine formations such as oil bearing formations, deep un-mineable coal seams, and deep saline aquifers.Sites where CO2 is stored could be closed and responsibility transferred with lower risk, higher confidence, thus greater insurability, if technologies existed that: i) would hasten the rate of CO2 trapping so long term stability could be reached in decades rather than centuries and ii) if rock formations could be sealed near wells, to prevent leakage through degraded steel and concrete in the closed injection well.Previous work by the fellow (Mitchell et al., 2008, 2009, 2010) has demonstrated such technology – via carbonate mineral forming bacteria and biofilms in the subsurface. Here, we have shown that carbonate mineral forming microorganisms and biofilms can enhance CCS via solubility-trapping, mineral-trapping, and CO2(g) leakage reduction. Such work has however, been performed under low pressure conditions for a simple brine composition.The CO2TRAP project aims to develop this green-technology further to address these knowledge gaps. We will;(i) Investigate the effectof brine composition on the biomineralization process(ii) Determine the effect of pressure on the biomineralization process(iii) Determine the stability of carbonate minerals to SC-CO2 / brine mixtures under reservoir conditionsThese data will enhance the EU’s ability to develop energy efficient, low carbon water and air treatment technologies through the 21st century for a long term environmentally sustainable future.