Dumping Black Water On The Ground?

I know of a person who did not like the car behind him following so close. Being a plumber by trade, he had a homemade electric valve system on the control panel and had his wife push the button for a second. Did I mention he failed to see the colored light array on top of the vehicle behind him?
It cost him a whole bunch of greenbacks to rectify the situation right down to paying for a hazmat crew to clean up the road.