ENERGY STORAGE Great news with major project for storage of energy - much needed to make solar and wind truly sustainable options as sources of energy. A thought on the proposed solution of pumping water in abandoned mine(s) up to later be reintroduced to the mine(s) via underground turbines: - When you bring water to surface for use (drinking, irrigation etc), the void created underground when the water is brought to surface is replaced by water from surrounding strata. - WHY would this not happen in the proposed energy storage solution proposed, when water pumped up from abandoned mine(s) a intended to be reintroduced back to the mine(s) via turbines? Why would the void created not be automatically replaced by water from surrounding strata? Best regards Richard