I work in Pest Control/Wood Destroying, and am often asked about moles. Everything I have read, leads me to believe, very little other than trapping will work. Many manufacturers of mice and rat bait will tell us that they will have a mole bait coming out soon, but this never seems to happen. Remember that Pest Control works on a triangle. You have food water and habitat. Remove one of these requirements, and the problem should resolve.
I have had people tell me that killing the grubs help, that chewing gum works, gas in a tunnel, and many more. Also those wind mills are supposed to drive the mole nuts from vibration. While I'm thinking of it, gas down a fire ant mound does not work most of the time, it just stresses the colony which buds and produces more mounds in practice.
Be careful what you place in the ground, or on top for that matter when trying to remove these moles. Read all the labels to any over the counter chemicals you may use. Be careful if you use bait that you do not kill other non target animals.
Best Regards
Bryn