The train was parked in Nantes, 13 km from Lac-Mégantic.

At Nantes there are two railtracks, one main and one siding.For some reasons the conductor parked the train on the main line...where there is NO derail

On the siding there IS derail. Should he have parked the train on this track, he would

have avoided all this mess.

The conductor was sleeping in hotel close to derailment site when this occurred.

This man has since disappeared...

I agree with you ebear, main cause is regulation that authorize train to be unattended.

It is inconceivable to leave 73 wagons full of crude oil to be unattended.Anybody could get close to the train and loose the wagon's brake