While there are many maps out there showing the flows around the Ohio River basin, the real danger from the vinyl fluoride spill is in the underground aquafers and watersheds. There are rivers of water underground that cannot be seen, that are mapped by the USGS, as shown here.
https://www.usgs.gov/mission-areas/water-resources/science/principal-aquifers-united-states
There are also watersheds and Basins that are formed by the gravitational forces on the surface of the earth, as you learned about the East West Continental divide in school. (Can't speak to those educated more recently) Also, less known in other areas of the country are the basins that comprise the Mississippi and Saint Lawrance rivers separated by the North South continental divide.
While the Ohio River contamination affects mostly the surface near the edges of the river, there is also seepage from the ground into aquifers either directly below the wreckage, or from water sources feeding into the aquafer via runoff.
The damage will take years to fully understand, but with the population of unknowing VAIDS patients, the effects of the carcinogens may be seen much sooner than expected. This is 5th gen warfare, most of our friends and neighbors have no idea what is even happening yet, or that anything IS even happening. We are part of an awakening, and unfortunately it is not the poorly defended that will be casualties of this war, it is the poorly informed.
Aquifer recharging is highly variable, depending upon sediments and bedrock. It can take weeks, or it can take years, for surface water to reach the depths of aquifers. At any rate, there is a purification benefit as the water travels through sand, limestone, etc. I think this is the least of the worries.