3.2 CO2 storage risk assessment

There are several recently published studies and recommendations concerning risk analysis of CO2 storage (e.g. OSPAR-FRAM 2007, EU CCS Directive 2009, USA Energy Department 2011, CO2Care 2011, MUSTANG 2012).

The prerequisite for establishing a CO2storage site is that no significant leakage will occur from the storage complex, and the risk assessment process is vital in order to ensure this requirement is satisfied. Therefore it is important to begin the risk assessment process early in the project, simultaneously with site characterisation of the storage complex. It must also be presented to the licensing authorities before a storage permit can be issued. A well-considered risk assessment includes all sorts of risk events that may occur at the storage site, from leakage of CO2 into the atmosphere to problems with the injection equipment and general health and safety issues. In this section the aim is to focus on risks relating to the geological issues of a storage project.

The risk assessment should include information about the CO2 injection, historical description of the oil/gas field if CO2 storage is implemented in connection with EOR, location of active and abandoned wells in relation to for instance, groundwater supplies, lakes, homes and infrastructure, the condition of existing wells, qualitative assessment of the geological modelling results from the site characterisation, etc. The risk assessment may also be used as a tool in the communication plan in order to increase public understanding and acceptance of the project.

Both OSPAR and the EU CCS Directive provide frameworks regarding the risk characterisation and risk assessment processes of a geological CO2 storage site. These are briefly described below.

 

in depth

3.2.1 Risk assessment under the OSPAR Convention

The FRAM of the OSPAR guidelines (2007) recommends that the risk assessment is undertaken during the entire life cycle o...

3.2.2 Risk assessment in the EU CCS Directive

In the EU CCS Directive, the risk assessment processes is a part of the site characterisation and assessment of the pote...