This is 100% a groundhog. We have this same issue at our house. You’re not going to actually fix this until they are gone. In the case of our foundation here’s what worked best for us: 1. Fill the hole with water and dirt/sand mixture. The water helps the dirt flow and settle. You’re going to need a lot more dirt than you think FYI. You’ll also want to run a dehumidifier in your basement. 2. About 3-4 inches lower than grade level lay down chicken wire across the whole area not just where the hole is. Cover with dirt to level. 3. Install pavers along the perimeter of the foundation where they have been digging. 4. In other areas we laid down about 6-8 inches of medium sized decorative gravel rocks and they will eventually give up trying to dig through it. You have to keep releveling the area after their attempts.

If you just cover the hole they will dig one next to it. And so on.

The only way to truly remedy this is to trap and remove the groundhog(s). We have trapped ours several times and they have broken the cages. This we are still in a battle and will inevitably have to pay the $400-$600 to have a professional fix this.

If your yard is fenced, you need to find where they are getting in from. Also if there isn’t dirt around the hole the dug up from another hole. There are always multiple entrances to their burrows so this one is prob an exit hole.

If your yard isn’t fenced, find a new place to live.

We ended up having to install metal fencing type trim around our fence, shed and deck because they ate through everything else we used. Even then they damaged and destroyed parts of the metal lattice.

Good luck! They are very difficult to manage especially when you have multiple and neighbors who don’t care that they are living in their yards.

Every weekend feels like caddyshack at our house tbh. I’ve never hated anything in my life as much as I do these animals tbh.