The Schreiber Washer/Compactor washes out organics and dewaters screenings in a batch sequence. Screenings enter the top of the unit and are agitated by a rotating shaftless screw in a trough being supplied with wash-water. As the screw rotates in a forward and reverse motion providing agitation, entrained organic material is released from the screenings. The organics now in suspension are drained back to the process stream for treatment by the process equipment. The washed screenings are transferred over a barrier at one end of the wash trough into the compactor section below. The screenings are subsequently dewatered by the action of a compactor screw, gravity and conical discharge, and then conveyed through a larger diameter discharge pipe to a screenings container. The washed and compacted screenings material is significantly reduced in both volume and organics, resulting in disposal cost savings, and will pass the Paint Filter Test.