Article: Union Pacific ran toxic chemical cars through Centennial Mills collapse zone despite promises, Portland says

couple of miles from here:

Citing Portland Fire & Rescue's hazmat coordinator, the letter said "residual" toxic material in a rail car can range from 1% to 8% of tank volume, and a single car at 5% residual could hold roughly 1,500 gallons of chlorine — enough, if released, to create a hazardous plume posing a severe threat to nearby residents and workers. The letter said engineers have confirmed ongoing deterioration of the structure, including widening cracks and active leaning toward the rail corridor, and that any vibration or impact near the site could trigger a collapse.