Atco Mining Inc. announced that it has completed a hydrogen storage capacity assessment for its salt structure at the Flat Bay Salt Project. The work was completed by the company's contracted consultant partner, RESPEC Consulting Inc., a global leader in geology, geophysical and engineering work and who has direct experience in underground hydrogen storage caverns. Based on the interpreted geology, operating pressure limits set by the Canadian Standards Association (CSA), and cavern dimensions, RESPEC generated preliminary cavern layouts and performed high-level thermodynamic calculations to estimate the maximum hydrogen storage capacity of the salt structure at the Flat Bay project site.

The cavern field layout depends on the areal extent and thickness of the salt structure. The cavern layouts generated for the Flat Bay project site salt structure are based on the following preliminary design considerations: (1) caverns are placed at an S/D ratio of 4 (where S is the distance between the center of one cavern to another cavern and D is the average maximum diameter of the two caverns), (2) caverns are at least a 1.5 cavern diameter length away from the salt dome boundary, (3) cavern diameter is limited to 80 m, (4) the cavern roof is located at least 200 m below the top of salt, and (5) caverns bottoms are at least 200 m away from the bottom of salt. Because the 2D seismic interpretation results decrease in accuracy with increased distance from the seismic lines, RESPEC generated conservative and optimistic cavern field layouts based on the distance from the seismic lines and distance from the core of the salt structure.

The conservative case only considers salt caverns closer to the seismic lines and within the salt structure core. Whereas the optimistic case also includes caverns away from the core of the salt structures. Based on the available geological information, the Flat Bay salt structure can potentially hold approximately: 7 caverns providing a total hydrogen storage capacity of 130,000 tonnes for the conservative case; and.

14 caverns providing a total hydrogen Storage capacity of 250,000 tonnes for the optimistic case. It is important to note that this cavern layout is preliminary and heavily based on the gravity and 2D seismic interpretation of the salt structure, which may change as additional geologic data are obtained. RESPEC anticipates that the preliminary cavern field layout and hydrogen storage capacity estimates will need to be updated as potential core wells are drilled, and more 3D seismic surveys are performed.