If they are going to exploit something like you describe, they will do it entirely using contractors.
The chances of this being accomplished in secrecy are approximately zero, at least for more than a week or two.
If they are just going to lock it up, fine. But are they going to lock everything up everywhere? Strikes me as unlikely.
They need the tax revenues too much.
It was reported or misreported that the drill site and oil find would be made part of the strategic petroleum reserve.
That could mean it will be locked up. I would speculate that the environmentalists that control Obama will want it locked up.