Subsurface sequestration of CO2 in saline aquifers or in oil producing units (for EOR) is proposed to help mitigate climate change. The long-term fate and impacts of injected super critical CO2 are uncertain. Our research assesses the potential for leakage of CO2 and dissolved organic contaminants of concern through seal rocks intended to contain injected CO2. We also assess the impact of CO2 on subsurface microbial communities that may participate in carbonation and pore filling or dissolution. We are addressing the following scientific questions.
- How to the hydrogeochemcial properties of seal rock affect the permanence of storage of injected CO2?
- What microbial communities are present in brine and oil producing reservoirs and how does CO2 impact those communities and their ability to catalyze formation of carbonate minerals?
- What is the solubility of organic contaminants such as polyaromatic hydrocarbons in supercritical CO2 and CO2-saturated brines at reservoir pressure and temperature?
- How does brine concentration and composition affect that solubility?