The hole for this has different requirements than holes for water and petroleum: you'd not want to drill one of these holes into an aquifer, because then it wou

The hole for this has different requirements than holes for water and petroleum: you'd not want to drill one of these holes into an aquifer, because then it would fill up with water. Oil and gas wells have to be drilled in specific places where the oil and gas are, naturally. In this case, you'd want nothing but a dry, empty hole. A dry, empty hole would be the kind of hole least likely to interact with anything underground. I'm not sure this has much to do at all with water and energy drilling. They're talking about using abandoned mine-shafts. Those are much wider and shallower than the kind of holes used to reach petroleum.