Try a Havahart live trap. They can be rented from many hardware stores. Once trapped, take the critter for a long ride and release. If not inclined to do this yourself, ask around, there are often people who take care of nuisance animals for a fee, and many times people who are licensed wildlife rehabilitators will do this for free. BTW, there is a good chance that you could have a porcupine instead of a woodchuck. Check for strong urine odors. Porkies really reek.