ECO2 is a European project improving the knowledge on environmental aspects of CO2 storage offshore, including the development and field trials of advanced monitoring techniques for the seafloor and shallow overburden. The consortium of 27 organisations just held their 3rd annual meeting at Salina, Italy.

The original objectives of the project are to investigate the likelihood of leakage from sub-seabed storage sites, to study the potential effects of leakage on benthic organisms and ecosystems, to use cutting-edge monitoring techniques in the field and develop a monitoring strategy, to assess the risks of sub-seabed storage, and to produce a best practice guide for monitoring environmental aspects of CO2 storage sites offshore.

The project is investigating the sites of two operating storage projects and one potential storage project, and natural seepage sites such as Panarea. A large amount of field data has been collected from 24 marine expeditions to offshore storage and seepage sites with a total ship time of more than 250 days, well as extensive laboratory studies and modelling work.

The project has previously attracted media attention because of its work in detecting and investigating a seabed feature called the Hugin Fracture in the North Sea, and determining that the gases and fluids being emitted were shallow in origin and not related to the Sleipner project 25km away.

The project has assessed the shallow overburden at the sites and investigated feature of interest such as pipes and chimneys, using techniques such as P-cable hjosir-resolution seismic and synthetic-aperture sonar. The work done so far is enabling a better understanding of fluid flow mechanisms in the shallow overburden, the environmental impacts of a CO2 leak, and the limited ‘footprint’ of such a leak.

I was particularly struck by the demonstration of the remote geophysical monitoring techniques for the detection of gas leakage from the seabed, and the ability to subsequently analyse and assess the geochemistry of the leakage gases and fluids, for example at the Hugin Fracture to successfully determine their origin. These capabilities can be coupled with the latest in automated underwater vehicles (AUVs) to enable the surveying of large areas. I think this project has significantly progressed the knowledge and capabilities for monitoring and environmental assessment of offshore CO2 storage.

The project will complete in early 2015, and the last year of its work will focus on synthesising the results and producing a best practice guide for monitoring and environmental assessment.

IEAGHG presented on its London Convention-related work at the meeting, and being a member of the Stakeholder Dialogue Board of ECO2, with the other members provided feedback for the last stages of the project. For more information see the project website http://www.eco2-project.eu .