Background to the Study

The IEAGHG Risk Management Network meeting brings together experts in the field of CCS from across the world to address the challenges faced with underground CO2 storage, with a particular focus on active and legacy wells.

The Risk Management Network meeting was held as an in-person event with a particular focus on the risk
of wells (particularly legacy wells) in a CCS project, looking at the topic from basin scale through to detailed
characterisation of well materials and monitoring. Attended by over 75 delegates from 15 countries, the
two day meeting was held at Heriot-Watt University in Edinburgh, UK. It was kicked off by a welcome
reception in the Lyell Centre (home to both BGS and the Institute for GeoEnergy Engineering) and was
followed by a field excursion to explore the geological history of Arthur’s Seat in Edinburgh and a tour of a
very new distillery located in an old train station within stone’s throw of Holyrood Park.

The meeting was designed to cover the following themes: industrial perspectives on risk management
and legacy well containment; how to identify, evaluate and abandon well bores for the future; long term
well integrity – performance and risk assessment; well materials and testing; the challenges of monitoring,
impact assessment and quantification; emerging solutions and approaches to monitoring; and finally a
panel discussion on communicating well-related risk to regulators and other stakeholders.

As usual at IEAGHG Expert Network meetings, key conclusions and messages were drawn and
recommendations were made. The concluding high-level messages noted that prospective storage sites
with the fewest concerning legacy wells will rank among the most attractive for early deployment, but
that availability of sites with higher quantity and/or lower quality of legacy wells might be unlocked as
costs fall and technology to remediate improves – decisions that can be supported using approaches
analogous to standard oil and gas industry ‘creaming curve’ analysis, as discussed later. Cements were a
key topic with encouraging laboratory testing on legacy wells and samples showing the effectiveness of
Portland cement as a barrier over time. Monitoring and monitoring plans were discussed and can be made
streamlined with time. Insurers and financiers are starting to create products and cross-cutting meeting
would be beneficial as are finding a common lexicon for communication. Standardising and streamlining
the permitting process was a recurrent theme. The participants also recognised the challenges remaining
including quantifying leakage rates, quantifying expected containment; how currently well-behaved wells
might be impacted in practice as we start to inject; impacts of doing remediation might be higher that
impact of leak (in the case of legacy wells), data management of monitoring data – e.g. how to get realtime
data to shore from landers, or how to deal with extremely large datasets (e.g. DTS).