Presentation Description
Near-surface environmental monitoring, targeting groundwater and soil gas, plays an important role in the Monitoring, Measurement and Verification (MMV) program at on-shore deep-well carbon capture and storage (CCS) sites. The purpose of environmental monitoring is not only for regulatory compliance but also to assure the public that injection activities do not impact the near-surface environment.
At the Otway International Test Centre (OITC), environmental monitoring has been conducted annually since before the first injection in 2008, establishing baseline conditions and obtaining 17-year data for soil gas and 18-year data for groundwater. Since mid-2020, the Deakin University team has collected groundwater samples from up to seven monitoring bores and eleven private bores of the local landholders.
A variety of parameters were gathered to assess groundwater quality, including major ions, trace elements, and tracers (i.e., SF6 and noble gases). Meanwhile, over 100 soil gas sampling points were installed across an area of approximately 3.8 km2, including dairy paddocks and roadsides. Samples were analysed for concentrations of CO2, N2, O2, CH4, and carbon isotopes in CO2 (δ13CCO2), along with the measurement of tracers in selected samples. Significant natural variabilities have been observed temporally and spatially within both groundwater and soil gas systems.
A multi-step verification process was employed to identify potential influence on the near-surface environment. The verification process incorporates tracer analysis, along with historical values, baseline values, and analysis methodologies established by researchers between 2008 and 2023. Research objectives were established to optimise monitoring strategies based on a substantial database, focusing on risk-based soil gas monitoring. To date, valuable insights have been gained throughout the work at OITC, providing lessons that are invaluable for developing cost-effective monitoring strategies in future largescale CCS projects.
At the Otway International Test Centre (OITC), environmental monitoring has been conducted annually since before the first injection in 2008, establishing baseline conditions and obtaining 17-year data for soil gas and 18-year data for groundwater. Since mid-2020, the Deakin University team has collected groundwater samples from up to seven monitoring bores and eleven private bores of the local landholders.
A variety of parameters were gathered to assess groundwater quality, including major ions, trace elements, and tracers (i.e., SF6 and noble gases). Meanwhile, over 100 soil gas sampling points were installed across an area of approximately 3.8 km2, including dairy paddocks and roadsides. Samples were analysed for concentrations of CO2, N2, O2, CH4, and carbon isotopes in CO2 (δ13CCO2), along with the measurement of tracers in selected samples. Significant natural variabilities have been observed temporally and spatially within both groundwater and soil gas systems.
A multi-step verification process was employed to identify potential influence on the near-surface environment. The verification process incorporates tracer analysis, along with historical values, baseline values, and analysis methodologies established by researchers between 2008 and 2023. Research objectives were established to optimise monitoring strategies based on a substantial database, focusing on risk-based soil gas monitoring. To date, valuable insights have been gained throughout the work at OITC, providing lessons that are invaluable for developing cost-effective monitoring strategies in future largescale CCS projects.