It turns out pipeline operators aren’t required to tell anyone:
After the dilbit gushed into the river, it began separating into its constituent parts. The heavy bitumen sank to the river bottom, leaving a mess that is still being cleaned up. Meanwhile, the chemical additives evaporated, creating a foul smell that lingered for days. People reported headaches, dizziness and nausea. No one could say with certainty what they should do. Federal officials at the scene didn’t know until weeks later that the pipeline was carrying dilbit, because federal law doesn’t require pipeline operators to reveal that information
You can’t get on an airplane with a bottle of water, but you can run pipelines all over creation without telling anyone what’s in them.
And corporations complain about over-regulation.