I believe the case you're speaking of actually happened in Western Oklahoma -- near LaVerne. Guy was driving a tanker, transferring sludge on a hog operation from a malfunctioning lift station to the lagoon.
Apparently slid into the lagoon on his last trip of the day. Everybody else went home and nobody missed him until he and the truck didn't show up the next morning. They eventually found the tire marks at the lagoon...and knew the awful truth.
They had to pump out the lagoon in order to recover the truck and ol' Joe Bob...
Not a pleasant story...