John is correct when he says to call the AHJ before starting any work. It is much easier than digging twice. I have people tell me all the time, "I took pictures!" The problem with that is after awhile, all the trenches look the same! I don't even look at pictures anymore. I would rather they use the sight pipe and back fill area that are critical for moving cars and machinery around the sight. Places like parking lots and condos where the trench is in the road, it would be to dangerous to leave the road open.