Good grief, obviously some of you have never been on a farm...
Note that dump stations are built with a concrete square surrounding the dump pipe, which is sloped toward the pipe and surrounded by a concrete curb to prevent sewage from flowing anywhere other than the pipe. This is the "spill zone".
IF the lady described by the OP had the TT close enough to the dump station so that the proceeds from rinsing that tank were emptying in this area, which she hosed off afterwards, I see no issues. That's as clean as I expect a dump station to be. The fact that she was standing in the runoff wearing flip flops is a little gross, and not something I would do, but the fact that she was doing it doesn't affect me as the next user of the dump station.
Best was the septic company on Long Island that had this slogan on the back of their pump-out trucks: "Your #2 has made us #1!"
