Oh, I thought you wanted to repair a damaged mole. ;-)

I have a friend that had moles digging up his yard and he bought a few of these electronic beeper units that apparent really annoy the moles. They make a "bee-dee-dee-deep" kind of sound to our ears. His yard is now free of moles.

We rototilled to even everything out and replanted the grass.

Ooops! ;-) Chalk one up to first time posting (grin) I REALLY want to know how to repair the lawn!! Thanks for the ideas!! The neighbors have a dog though, and I don't want to drive him batty?

My kids have never been injured running around on our moonscape. I don't think you can ever be mole free; if you get rid of one, another one moves in. When you see the mounds, you can spread out the soil so it doesn't leave a hump, but as far as the ground being lumpy from past tunneling, I think about the only thing you can do is till and rake it smooth, but you'd still get moles coming through. Maybe you could shave off the high points left by the mounds of soil they push up to smooth it out a little, but it could be a lot of work.
Some people kill off the grubs in the ground that they feed on, but they also feed on worms and I have no idea if the same product kills them also. I wouldn't want to kill off the worms.
Good luck!