How far will a chipmunk burrow underground?

I don't know but it's definitely not deep enough. They seem to love to have a runway right underneath the concrete walkway. So as

soon as you run over it with the riding mower, you've got a nice crack from one end to the other.

I had a call yesterday. The holes were 20-30 feet from the above ground pool. There's a small cave-in/depression just inside the pool. I didn't think they would burrow this far, but after sleeping on it, they may have. Any other input?

I think they burrow very far over time, when I hunt them with my pellet gun in my backyard I hear one chirping 10 yards away in thick brush it then sees me try to move to see it and the sound stops for 10 seconds or so then it starts chirping 20 yards away and it has been 30 or so before so yes they will burrow that far.

Cole--I see that you're 75/100 on these things. Are you using anything other than the pellet gun? I am doing quite well with small cages and OK with rat traps. We're loaded with them this year.

Oh this is my favorite subject lol I use a shotgun since i live on 8 acres but use pellet guns sometimes i do best with marshmallows in cages i will post a pic of how i set hem if you want and use rat traps with a ming marshmallow pushed into the trigger so when they pull it away they get caught. If you have any more questions I'm the man well actually kid to ask lol

Seriously ?! Shooting chipmunks? Not a professional approach, IMO.
Do yourself a favor. Get some one way door 4X4X15 AES traps and some of LT's Blaq Walnut bait. They don't make a chipmunk that will pass it up!