look for a square walled in area inside should be a lever to disable the anti-dragon shield. But once you get to the mine you need a key. Im on the same quest but i cant find the key to open the mine.
If you are referring to the mine (baal's cave) in broken valley after broken valley destruction, just fly back to the quarry building and look for guild master william in the building. He will give you a key for that. I think you guys need to be more specific in your questions.
