Visible crew member, or an extra?

From the scene where the black Chrysler with the Pontiac front clip crashes into the moat outside the refinery: camera view is from behind as the car falls out of the frame, and for a few moments a person dressed in white is clearly visible, standing in the distance. I can't tell if they're inside the refinery fence - which would mean they were probably an extra - or outside it - which indicates they might have been a crew member overseeing the stunt.

What do you think?