A skid steer was being used to transport crate brackets for staging onto installed piles. An employee approached a crate to get two brackets. He picked up the brackets and turned left to walk and place the brackets on a pile. The skid steer traversed forward, making contact with the employee's right boot and causing him to fall on the ground. The skid steer continued to move forward, driving over the employee's right leg just above the knee. The employee sustained a broken leg.