See this from the news today, Trump administration repeals train safety regulation, triggering new oil spill fears.
We have had more than one oil train derailment, not all of which has led to an actual spill, but the one mentioned in the story above that was immediately adjacent to the Columbia River got many people's attention.
I do know that a 100-car oil train packs a lot of energy as it is rolling down the tracks and stopping is no easy matter. Having a digitally controlled air brake system is the issue and that is the requirement being waived at this point.
Back in 2017, my organization, the Center for Regional Disaster Resilience (CRDR) held an Oil Train Safety Symposium that drew a crowd and had excellent participation from numerous panels. See this NBC News story on that event and the Symposium After-action Report.
At this point it will likely require another incident that causes deaths like the Lac-Mégantic rail disaster before the rules change again. As one fire marshal told me, "Every line in the fire code is written in blood."