Abstract: A multiple deck trommel screen is provided having at least an inner course screen and an outer fine screen, both having a diameter greater than the rotating drum to which they are attached for separating fines from course material. A deflector plate is provided at the end of the trommel screen for impingement of air-borne particles so that they fall on the inner trommel screen. A first hopper is provided under the outer trommel screen for receiving the fines and a second hopper is provided beyond the end of both of the trommel screens for receiving the course material. The outer trommel screen is made up of generally flat screen sections which extend as chords around the periphery of a trommel screen frame.