A number of geochemical modelling codes have been used for CCSCarbon dioxide Capture and Storage related work. TOUGHREACT is an enhancement of the multiphase fluid and heat flow code TOUGH2 to reactive transport (Xu and Pruess, 20012001 - T. Xu and K. PruessModelling multiphase non-isothermal fluid flow and reactive geochemical transport in variably saturated fractured rocks: 1see more). The version developed by Xu et al., 20062006 - T. Xu, E. Sonnenthal, N. Spycher and K. PruessTOUGHREACT -a simulation program for non-isothermal multiphase reactive geochemical transport in variably saturated geologic media: applications for geothermal injectivity and CO2 geologic sequestrationsee more allows modelling of supercritical(CO2) Conditions where carbon dioxide has some characteristics of a gas and some of a liquid CO2Carbon dioxide injectionThe process of using pressure to force fluids down wells in a reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids by considering hydraulic processes, thermal variations and chemical phenomena. Both dissolution and precipitation processes are integrated within this code, together with a feedback mechanism for porosityMeasure for the amount of pore space in a rock and permeabilityAbility to flow or transmit fluids through a porous solid such as rock changes. Other modelling codes continue to be developed; SIMUSCOPP was introduced by Le Thiez et al., 19961996 - P. A. Le Thiez, G. Pottecher and J. M. CômeValidation of a general 3-D numerical model for simulating organic pollutants migration and application to site remediationsee more, STOMP by White and Oostrom, 20062006 - M. D. White and M. OostromSTOMP Subsurface Transport Over Multiple Phase: User's Guide PNNL-15782 (UC-2010)see more, HYTEC code by Lagneau et al., 20052005 - V. Lagneau, A. Pipart and H. CataletteReactive transport modelling of CO2 sequestration in deep saline aquiferssee more. Johnson et al., 20012001 - J. W. Johnson, J. J. Nitao, C. Steefel and K. G. KnausReactive transport modelling of geological CO2 sequestration in saline aquifers; The influence of intra-aquifer shales and the relative effectiveness of structural, solubility, and mineral trapping during prograde and retrograde sequestrationsee more; Johnson et al., 2004) developed a software package based on the codes of NUFT. Audigane et al., 20062006 - P. Audigane, I. Gaus, I. Czernichowski-Lauriol, K. Pruess and T. XuA long-term 2D vertical modelling of the CO2 storage at Sleipner (North Sea) using TOUGHREACTsee more; Audigane et al., 2007 have presented a 2D axial model using TOUGHREACT and 3D model using TOUGHREACT and code TOUGH2/EOS7C (Audigane et al., 20092009 - P. Audigane, J. Lions, I. Gaus, C. Robelin, P. Durst, B. van der Meer, K. Geel, C. Oldenburg and T. XuGeochemical modelling of the CO2 injection into a methane gas reservoir at the K12-B field, North Seasee more), White et al., 2001; White et al., 20052005 - S. P. White, J. Allis, R. G. Moore, T. Chidsey, C. Morgan, W. Gwynn and M. AdamsSimulation of reactive transport of injected CO2 on the Colorado Plateau, Utah, USAsee more have developed the reactive transport code CHEMTOUGH and Nghiem et al., 20042004 - L. Nghiem, P. Sammon, J. Grabenstetter and H. OhkumaModelling CO2 storage in aquifers with a fully-coupled geochemical EOS compositional simulatorsee more have developed and used the commercial code GEM-GHGGreenhouse gases: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydroflurocarbons (HFCs), perfluorocarbons (PFCs), and sulphur hexafluoride (SF6).