Advances in deep CO2 leakage impact on shallow groundwater quality
摘要
Due to the existing faults,fractures and penetrating wells in the cap rock,the deep stored CO2 can leak into a shallow aquifer,change the acidity and the distribution of hazard components concentration in groundwater.According to the literature,the studies in this area are in their infancy,and the results from lab and field experiments,numerical simulations and natural analogues studies show that,the intrusion of CO2 into a shallow aquifer would decrease the pH and elevate the trace metal components concentrations significantly.However,the concentrations rarely exceed the drinking groundwater limits.Because of the significant differences between the mineralogy in different aquifers,detailed studies should be done on the risk assessment of carbon dioxide leakage of special aquifers,and point out that further study is needed based on the limitations of the current studies.