It is highly unlikely that any contamination would reach that far, vinyl chloride levels measured by the EPA already show that the remaining surface water contamination near the site is limited to the immediate area near the spill and the remaining surrounding surface water contamination is minimal.

https://response.epa.gov/sites/15933/files/East%20Palestine%20Derailment_Surface%20Water%20Analytical%20Results%20Summary_rev02.pdf