In order to address properly the Risks related to underground storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere of CO2Carbon dioxide in the Kalundborg case study the Quintessa database (www.quintessa.org/consultancy/index.html?CO2GeoStorage.html) of features, events and processes (FEPs) was used (Chadwick et al., 2008), with the chosen FEPs being included for their relevance to the long-term safety and performance of the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere system after injectionThe process of using pressure to force fluids down wells of CO2Carbon dioxide has been completed and the injectionThe process of using pressure to force fluids down wells boreholes have been sealed. Some FEPs associated with the injectionThe process of using pressure to force fluids down wells phase are nevertheless considered where these can affect long-term performance. In the Kalundborg case study, the most important FEPs resulting from the auditing are as follows: (i) geological features, (ii) overpressuring - reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids characteristics, (iii) effects of pressurisation of reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids on caprockRock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir, (iv) undetected features, faults at top of reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids long-term fate of CO2Carbon dioxide, (v) reversibility - fingering leading to CO2Carbon dioxide escaping the trap(geology) A geological structure that physically retains fluids that are lighter than the background fluids, e.g. a convex fold, (vi) impact on society and humans, (vii) public opposition to the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere project, and (viii) impacts on humans - health effects of CO2Carbon dioxide. In addition to the riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event performed through the Quintessa database a number of other project risks has been considered. The project in Kalundborg is just a riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event identification case study.