The study of the hydrogeology of the Mid-Devonian aquifer in the Milo-Clarke Lake area of northeast BC helps illustrate the regional flow pattern, the hydrostratigraphy and the storage capacity of the aquifers, properties that would affect the injection and retention of carbon dioxide and hydrogen sulphide at rates of approximately 2.2 million tonnes acid gas per year over a 30-year period. Three porous and permeable aquifers with intervening aquitards are recognized in the Milo-Clarke Lake area bank: the upper porous (Slave Point equivalent), the middle porous (Sulphur Point equivalent) and the lower porous (Keg River equivalent) units. The most permeable unit is the middle porous aquifer, which has a permeability of around 300 mD over a thickness of 60m. Stratigraphic columns, histograms, pressure vs. elevation graphs, cross-sections, scope models and structure maps are all used to illustrate study results.