screen 36 and fall to fine screen 38 small particles 80 pass through fine screen 38 onto collecting plate 40 and aided by gravity and the vibration of screen assembly 34 descend off lower end 46 and onto conveyor 56 small particles 80 collect on conveyor 56 and are transported over distal end 62 thereof and into trench 12 intermediate particles 78 do not pass through fine screen 38 but instead descend over incline 50 and into inlet 52 of crusher 54 where intermediate particles 78 are pulverized into pulverized material 82 pulverized material 82 collects on conveyor 58 and is transported over distal end 64 thereof and into trench 12 the specific range of particle sizes in the coarse medium and fine grades of material will depend on the particular needs of a user of padding machine 10 and the environment in which machine 10 is employed in general the fine grade of material is selected to be a material suitable as a padding material with no further processing the medium grade of material is selected to be a material with sizes of intermediate particles 78 too large for use as a padding material but small enough to be efficiently pulverized by crusher 54 into pulverized material 82 itself utilizable as a padding material the coarse grade of material is selected to be a material with sizes of particles 76 too large to be efficiently processed by crusher 54 alternatively where a large amount of fine grade material is present in spoil 74 some particles having a size that is efficiently processible by the crusher may be included in the coarse grade of material in order to reduce the workload.