The HP 1 works (sorta) fine with the South Dakota system. If I had to bet, you may need to explore an antenna option depending on where you actually have the receiver. Good way to find out is lock your scan on the South Dakota State Radio System and pay attention to the signal bars in the upper right hand corner of the radio. While it's scanning, you should see some activity on the signal bars. If not, probably an antenna/reception issue.
The other possibility is how you have the range set up. Crank it as high as it goes and see if anything changes. I think the highest you can go is 30 miles.
If those two don't work, trick the radio into thinking you are somewhere else. Enter a zip code closer to that Summit tower and see if anything changes.
Overall the radio is pretty foolproof from a programming perspective. You just have to find the little tricks in your area to make it happy.
Hope this helps, good luck.