The main objective of this report
is to compile and review existing and emerging geotechnical methods
for the monitoring of CO2 geological storage. It includes
examples of general concepts and site-specific applications. This
introductory chapter provides a summary of the general context,
conditions and requirements for monitoring of CO2 storage. Monitoring purposes
include health, safety and environmental provisions (HSE),
quantification of emissions according to the Emission Trading
Scheme (ETS), operational and contingency monitoring and
information of local citizens. The legal acts and regulations for
the various subjects of protection are listed briefly.
The EU Directive on
CO2 Geological Storage requires that monitoring plans are to
be based on risk assessment. Thus, HSE monitoring must pay special
attention to protected subjects and potential pathways for leakage,
e.g. spill points, fractures and faults, weak points or
gaps in caprocks or (abandoned) wellbores. An overview of the
potential impacts of leaking CO2 are given from different
perspectives - namely the HSE, ETS and operational perspectives,
considering different compartments, e.g. the reservoir,
neighbouring aquifers, (abandoned) wellbores and near-surface
eco-compartments. In addition to potential impacts by CO2, risk
assessment and monitoring need to take into account potential
impacts related to associated incidental substances ("impurities"),
mobilised substances and displaced fluids. Potential impacts may
also include movement and deformation of rocks caused by changes of
fluid pressure in the reservoir and surrounding rocks.
A comprehensive monitoring concept considers all monitoring
purposes in all spatial compartments and all storage phases.
Site-specific monitoring plans have to enable the tracking of the
migration of fluids in the subsurface and adapt to the dynamic
evolution of a CO2 storage site. Monitoring techniques must
provide information on the storage complex performance and on
substances and processes of concern. The elements of such a
comprehensive monitoring concept are outlined and summarised in an
overview table that can be used to check site-specific monitoring
plans for completeness.
The main objective of this report is to compile and review existing and emerging geotechnical methods and concepts for an evaluation of the performance of geological CO2Carbon dioxide storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere sites. The report includes a summary of the general context, conditions and requirements for monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions, and it provides an overview of proposed general monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions concepts. General monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions concepts are useful for the development of comprehensive site-specific monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions plans and the selection and application of appropriate technical tools to consider all monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions purposes and address all identified risks. The provisions of the EU CCS DirectiveDirective 2009/31/EC of the European Parliament and of the Council of 23 April 2009 on the geological storage of carbon dioxide and the relevance of other guidelines and regulations in place for procedures to set up site-specific monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions plans are discussed.
In this report, monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions techniques are introduced and discussed in the context of specific compartments and/or monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions purposes, like e.g. monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions the CO2 plumeDispersing volume of CO2-rich phase contained in target formation migrationThe movement of fluids in reservoir rocks in the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids, monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions of faults and abandoned wells or monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions of separate freshwater aquifers above a CO2Carbon dioxide storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids. More detailed information about different monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions methods can be found in the IEA GHGInternational Energy Agency – Greenhouse Gas R&D Programme technical report 2012/2 (IEAGHG, 2012) prepared by members of CO2GeoNet.
The technical descriptions of monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions methods in this report include examples for specific applications or monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions tasks and for the evaluation of the performance of geological CO2Carbon dioxide storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere. They are supplemented with examples of site-specific monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions applications at demo or pilot CO2Carbon dioxide storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere projects and test sites.
Two examples for potential future storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere sites illustrate the procedure of setting up site-specific monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions plans, meeting multiple monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions purposes. These examples were selected to represent the two major storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere options in Europe and worldwide namely saline aquifers and depleted(hydrocarbon reservoir) one where production is significantly reduced gas fields.
The report and its conclusions and recommendations shall stimulate the ongoing dialogue between regulators, operators, researchers and developers of monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions tools for a long-term, safe CO2Carbon dioxide geological storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere.