just because you have a drilling lease it does not mean you can drill, i have stock in a small oil company that had leases in state lands off Florida, every time they tried to drill the environuts with the help of the state would file another law suit and drag it out for another 12-18 months in the courts, this went on for more that 25 years.
Finally the state was ordered by the courts to let them drill or buy back the leases, the state used taxpayer money ( what else) to buy back the leases.