EE WAS OPERATING A TRACKMOBILE COUPLED TO AN ENCLOSED RAILCAR. WHEN THE TRACKMOBILE WAS UNABLE TO ADEQUATELY BRAKE THE RAILCAR, IT BEGAN TO SLIDE AND COLLIDED WITH ANOTHER PARKED RAILCAR. UPON IMPACT, THE EE HIT THE LEFT SIDE OF HIS FACE AND HEAD ON THE WINDOW AND FRAME OF CAB. FIRST AID ONLY UNTIL 12/2/02.