Student or Learner
"But such uprisings as the Ole Miss riots seldom come without victims. It had been a nasty night of fighting and resentment, and trails of blood and a ground layer of thick, powdery teargas residue lingered that following day. In the end, there were two people dead and 166 wounded."
'a ground layer' should mean roughly ' a layer that lies on the ground'.
Have I understood it correctly?