The UKSAP (UK Storage Appraisal Project) objective was to provide a fully auditable and defensible overall estimate of UK CO2 storage capacity in offshore geological formations. The large number of potential storage sites meant that storage capacity, security of containment and economics could not be investigated for each site in turn. Rather, a few simplified, representative models known as Representative Structures (RS) were constructed. Using methods derived from hydrocarbon reservoir engineering, these simplified models were then used in many flow simulations to investigate the impact of a wide range of reservoir and fluid parameters, which either have not, or can not, be measured accurately. Two detailed reservoir simulation models known as Exemplar Models were also builit. These are actual sites with data encompassing geological structure, and reservoir architecture and quality, as indicated by available 3-D seismic and borehole data. The Exemplar sites are Bunter and Forties. Each were modelled with proprietary software Eclipse and Petrel. The UKSAP results have been made available in the CO2Stored database. http://ukerc.rl.ac.uk/DC/cgi-bin/edc_search.pl?WantComp=73 UKSAP data available here (UKERC Energy Data Centre): - Exemplar model data for Bunter and Forties sites, with each site available in Eclipse and Petrel data formats. - Selected UKSAP project reports.