Heard a crew some when they were paving and striping last month just a couple of miles from home. Looks like they use listed frequencies but, only simplex operation, no repeater use. I can remember hearing crew from Joppa salting roads all over North Alabama back in the 80's & 90's and knew where any road issues were. Wish they would go back to that as website(ALDOT'S) is a pain to use.
Well they probably using some other system for their daily ops. I'll leave them in my scanner for now and next time we have snow or ice event I'll monitor them if i don't hear anything then I'll remove them.
The only time I hear anything it is just the road crews talking between themselves and they are less than 8 miles away. Think only reason I pick them up that far I we use a mag mount scanner antenna that is on metal roof of house.