The only exploit i can think of is that if you have a hit on you, you just go in there.
or that hitman can't kill people in the mines who have a hit on them
Then maybe make a rule about that but at lounge you were allowed to do that. A admin revision looking for it will be useless becouse admins want rp, sometimes like in S2 is rare see admins online. Or will be a lot of work but a new type of miners like master miner (like master thief) and you only can become it if you don't have hits. Will be the same if someone place a hit on you but I don't think is gonna be a problem becouse if someone place a hit of 5m for player X a Hitman player Y can wait at the new mines doors.
So in my opinion is not gonna be a big problem