How deep are my traps?

Been chasing some moles from I don't know where for a week. Today I discovered what might be my problem. Digging down to a run about 8 inches down I went too far and discovered another run crossing across about 6 inches deeper. I set 2 traps at each level. On another site in the yard I dug down to a run and then went deeper. Sure enough, there was another run that didn't seem to be connected to the run above it. I have seen runs 3 feet down when cutting through banks for roads. Both hills near where I put these traps were large mounds suggesting digging their nests. A possible problem is my arms are not long enough to place traps if these runs go much deeper. Have any of you good fellows had similar experiences and if so any tips for me. By placing my sets in the lower runs toda I have hopes for tommorow.

How deep is the frost line there?

I probably don't set 'em that deep unless there's no surface runs. I never have to dig much to get OOS traps set.

Might get as low as 30 degrees for a week once a year as it did this year in January.