|how do I get rid of them
they have uprooted my lawn
|Voles are tiny creatures, and are sometimes referred to as field mice. They don't dig tunnels or make large mounds like what you describe. Moles don't always make visible, above-ground tunnels, either, but can simply make mounds of soil, with a hole in the top, along their paths. If the mounds are fan-shaped with a hole near the edge, you probably have an infestation of gophers. Woodchucks are a bit more circumspect, and prefer to hide their holes in brushy or stoney places. I hope this helps you identify your subterranean visitor.
Trapping is the only sure-fire way of getting rid of moles. If it's any consolation, moles like moist, organic soil full of grubs and other delicacies. So, their presence is a compliment to your abilities as a gardener. To trap moles (scissors-type traps are most effective), find the main run by probing the soil between mounds and placing your trap there. Moles dig seldom-used tunnels off the main run, so you may have to place the trap several times before you discover their main run. It takes time and patience, but you can trap and kill the moles that have taken up residence in your yard.