"All planes leaving Chicago required a two-step process before takeoff: De-icing with a mixture of about 50 gallons of propylene glycol and water heated to 180 degrees to remove snow, ice and other contaminants; followed by about 25 gallons of anti-icing fluid to prevent ice build-ups while planes are on the ground, said Jack Lampe, director of ramp services for United." . . . . .