An employee and a crew were on a route servicing residential recycling operations when they came to a stop with three recycling cans. After they finished dumping the materials into the back of the truck, they walked back to the vehicle's back step. The injured employee mounted the driver's side rear step and the truck's hopper blade actuated while the injured employee's left hand was touching the slide track. The blade came down the track and severed the top portion of the injured employee's index finger, resulting in a partial amputation above the knuckle.