Visible crew/equipment: At Rampart, when Dixie walks over to Dr. Brackett, who stands behind the station, the tape mark is visible on the floor, just before she steps precisely on it.
Visible crew/equipment: A few shots after Johnny informs Brackett of the victim of the radiation incident, there's a shot of the ER with two orderlies pushing a gurney towards the camera, and the two actors' tape marks are visible on the floor at the bottom of the screen, just before Brackett and Dixie stop there, when Brackett tells Dix to notify the radiation security guard.
Answer: It is standard practice to wet down driveways so that they stand out in a long shot.
stiiggy