I have no idea if this is related or not:
Last summer they tore up and replaced a roughly 5 mile stretch of road near here. When they put the new road surface down they installed these metal
plates in the center of the road spaced about 1/8 mile apart. Each plate measures about 5" x 5" there are numbers on each one, the surface of the
plate is even with the road surface. Nothing that makes sense of why they are there though.