The vehicle collision which closed Highway 7 Thursday turned out to be a fatal one. A 2003 Ford Taurus was travelling eastbound on Highway 7 when the vehicle struck drifting snow. The driver lost control and collided with a westbound tractor trailer unit in the westbound lane.The driver of the passenger car, 34-year-old Melanie Watson from Tay Valley Township,  died at the scene. The OPP’s Technical Traffic Collision Investigators were on scene to assist in determining the cause of the crash.  A resulting diesel spill required environmental clean-up.