Also worth noting about this accident... the ensuing fire and colision damage caused both lanes of US36 (AKA The Boulder Turnpike, a limited access divided highway) to collapse onto the tracks. This is the main route between Boulder, Broomfield, and Denver, and is a major traffic route. Immediately after the accident, the state built a temporary detour to the side of the bridge which was guarded by crossing signals while the bridge was replaced. The gravel train was a normal daily train (M-F) that came off a branch line into Longmont, then went into Denver.