Emergency crews discovered that a car loaded with polyisobutylene was leaking into a section of Wolf Creek in Otoe County. Polyisobutylene is a durable, flexible synthetic rubber used in products like adhesives, inner tubes, chewing gum, and fuel additives. The leak appeared partially contained by a natural dam approximately ¼ mile downstream at the county line. Polyisobutylene is generally classified as low in toxicity to humans and the environment under normal conditions.

Murray Fire responded and deployed booms (floating barriers) to help contain the spill and facilitate cleanup. No injuries were reported. The cause of the derailment is believed to be thermal misalignment, which occurs when heat causes the rails to expand and push out of alignment, according to the Union Pacific Police's interview with the train crew. HMR Hazardous Materials Response and Union Pacific Haz-Mat crews are managing the cleanup. The cleanup efforts are ongoing and it is unclear when the tracks will reopen.