Ground Hog Deterrent

If you have any cats or know someone who does, used kitty litter put down the holes will drive them away.

It's unlikely they were dropped off. That hardly ever happens. More than likely, it had babies. We had one in our barn last year and I put mothballs down the hole repeatedly. I hear ammonia on an old rag also works.

If you are home a lot, I wonder if harassing them like crazy would work? Dropping mothballs down their hole; and dropping a (lit) firecracker down the hole every chance you get, running the hose down their hole, and so on. You might call the PA Game Commission and see if they have suggestions. Otherwise, your best bet is going to be "lethal force", or moving them yourself, which is technically illegal in PA. I don't know if harassing them would be enough.

You may have had drop-offs, but I doubt it; more likely it had babies last year, and this year the entire family has returned.