Bannister, S.C.; Nicol, A.; Funnell, R.H.; Etheridge, D.; Christenson, B.W.; Underschultz, J.; Caldwell, T.G.; Stagpoole, V.M.; Kepic, A.; Stalker, L. 2009 Opportunities for underground geological storage of CO2 in New Zealand : report CCS-08/11, monitoring and verification methodologies. Lower Hutt, N.Z.: GNS Science. GNS Science report 2009/64 91 p.
Abstract: Monitoring and Verification of carbon dioxide (CO2) stored in sub-surface rock formations will be an integral part of potential geological sequestration projects in New Zealand. Its primary purposes are to track the location of the injected CO2 plume in the subsurface and to detect any CO2 seepage from the primary seal through to the overlying strata and to provide assurance that none of the injected CO2 is reaching the ground surface (or sea bed). Information arising from Monitoring and Verification (M & V) offers a means of managing the injection process so that, for example, reservoir pressures and CO2 migration rates remain within predefined limits. Monitoring and Verification is important because it provides assurance to stakeholders that the storage process is safe, will not have detrimental impacts on the environment or existing resources, and confers a benefit to the Earth’s climate by reducing greenhouse gas emissions. Legislation will be used to ensure that these requirements are met and that risks are minimised. M & V programmes could span 20 years or more, commencing prior to injection in order to establish baseline conditions and finishing when the storage site is closed. In New Zealand these programmes are expected to be similar to those conducted overseas at Weyburn (Canada) or Otway (Australia), for example, but may differ in detail due to our geological and cultural settings. The M & V techniques best suited to CO2 storage sites in New Zealand will depend on a number of factors including the type of storage (e.g., deep saline reservoir or depleted oil and/or gas reservoir), the depth of the storage container, the location of the site (e.g., relative to population centres, environmentally valuable areas, the location of other subsurface resources (oil, gas, coal, water and geothermal), local active faults, culturally important sites and the coastline), legislative requirements, public attitudes to Carbon Capture and Storage (CCS), and the economics of these projects. As no potential storage sites have so far been selected in New Zealand this report focuses on identifying those M & V techniques that are likely to be of most use, comprising general descriptions of the main techniques (in Appendix 1), discussion of their application and recommendations outlining techniques suitable for use in New Zealand. (auth/DG)