Experimental process parameterization of a 3D site-scale model on effects of a compressed air intrusion into a shallow aquifer

Gases stored in the subsurface for balancing power fluctuations potentially escape from their reservoirs and affect protected groundwater resources. Here we presented an integrated experimental and modeling approach examining the site-scale effects of a compressed air leakage into a shallow aquifer. A main consequence may be pyrite oxidation, which can be strongly inhibited by surface passivation in carbonate-buffered aquifers. Based on laboratory results, predictions for changes in groundwater composition at site-scale and suggestions for a leakage monitoring were presented. Our study found this workflow consisting of experiments and numerical simulations to be valuable for predicting geochemical consequences of gas leakages.