If the smell is from old grease & oil, and you want to get rid of it, do you have a tool-rental store nearby?
If yes, see if they have a 200+ F-degree gasoline-powered pressure washer.
If they have one, and you have a remote/safe location to do the spraying, it will remove everything down to metal/paint.
I did it on/over a stone driveway - no concern about the residue.
