All three options (1, 2, and 3) can be potential sites for carbon sequestration Abandoned and uneconomic coal seams: These underground coal mines already have existing rock formations suitable for storing carbon dioxide. Since they are no longer operational, they can be repurposed for CO2 storage, potentially with the added benefit of enhancing methane capture from abandoned mines. Depleted oil and gas reservoirs: Once oil and gas reserves are depleted, they still have porous rock structures that can trap injected carbon dioxide. Repurposing these reservoirs for carbon storage leverages existing infrastructure and reduces the need for drilling new wells. Subterranean deep saline formations: Deep saline formations are layers of rock saturated with briny water, far below freshwater resources. Their geological properties allow for the storage of large volumes of carbon dioxide with minimal risk of leakage or contamination of freshwater sources.