Overturned Tractor Trailer on 95

At 02:43 Friday morning W503 was dispatched to a reported Auto Accident on I-95 Northbound at the 149 MM. While responding Prince William County EOC advised that this was a reported Overturned Tractor Trailer. W503 arrived on scene to find a piggy back tractor trailer on it's side over the embankment. The tractor trailer had rolled over once and ended up on it's side being stabilized by trees. The driver was out of the vehicle and walked away uninjured. W503 placed all units in service and remained on scene for P.D. to arrive. No hazards were found. W503 cleared at 03:05.