anyone know how to get rid of a groundhog?

a fence is the long term fix, but it has to go down as well as up - bury the bottom at least a foot and bend it outward in an L, or they dig straight under. clear brush piles and long grass near the garden so there's less cover. live traps work, but check the rules where you are, relocating wildlife isn't legal everywhere. fill the burrow only once you're sure it's empty.