Calgary narrowly escaped a similar fate, when a bridge collapsed under six oil tankers, five of which were full of combustibles. Kudos to the Calgary crew, who cautiously anchored the tanks, drained them, and moved them.
Yes, the rail people said it was safe and good to go and then the bridge buckled. Apparently "safe" means "it's too dangerous to inspect, let's try sending a train across it".
Being safe isn't how they make their money. The cleanup and disaster is handled by local / federal tax payers.
It's why you need STRONG legislation and governance of oil-companies too, something with teeth - they need to know they will lose big time if an incident happens so they do the cost-benefit analysis correctly.