A component of Agent Orange, 2,4,5-T was produced by Philips-Duphar (A chemical subsdiary of the industry giant) in the Netherlands. At the end of the Vietnam war the remaining stock was dumped in a polder just North of Amsterdam. When the scandal broke it was too late and the chemicals had reacted to form various dioxins which had leached in a gigantic plume into the ground water around the town of Broek In Waterland.
To this day the area where this all happened is off-limits, even though the soil has been excavated to many meters depth. This will likely be a permanent feature in what used to be one of the Netherlands nicest areas to recreate.
Photo of the site during the cleanup:
http://siebeswart.photoshelter.com/image/I0000jbBzIgQOwR4
This is the entrance to the site as it approximately looks today:
https://www.google.com/maps/@52.42447,4.991151,3a,75y,103.82...
It's one of the most expensive toxic waste operations ever in Europe and the most expensive one to date in NL.
People were living within 100 meters of this dump!
And that dump is a small fraction of what was dropped over Vietnam.