Establishing a site-specific groundwater monitoring protocol sensitive to changes in the groundwater chemistry related to potential leakage and also sensitive to natural variability will be imperative for developing cost-effective and robust testing and monitoring plans.
In CCUS projects, a site-specific testing and monitoring plan is mandatory to ensure the protection of underground sources of drinking water (USDWs) from Class VI injection well practices. As these projects have long durations with multiple phases, it is imperative for the groundwater monitoring program to be cost-effective with a robust sensitivity to detect any leakage.
Previously demonstrated changes in pH, carbonate chemistry, and certain trace elements (i.e., those that form strong-complexing anions) are geochemical indicators of initial CO2 leakage in relatively dilute aquifers. In this case study, SCS Engineers examine the sensitivity of dilute aquifer chemistry (major and minor cations and anions) to the leakage of CO2 and brines from the injection formation. We use an inverse thermodynamic modeling approach to simulate the effect of the progressive intrusion of CO2 and brines from the injection zone on the geochemical composition of the overlying dilute aquifer waters. From this, we can infer which geochemical parameters are most likely to be affected by the potential intrusion of CO2 and brines.
To attend this live presentation of Geochemical Effects of CO2, register for the upcoming National Carbon Capture Conference on November 8-9 in Des Moines, Iowa. Visit SCS Engineers at booth 120. Meet Kacey Garber.