WET & MUDDY & RAINING AND HE WAS CLIMBING DOWN THE DOZER TRACKS AFTER SERVICING THE EQUIPMENT. HIS BOOT SLIPPED OFF THE TRACK & HE HAD TO JUMP LANDING ON THE GROUND. HIS RIGHT KNEE FOLDED UNDE R HIM. HIS KNEE STARTED TO SWELL AND HE DROVE HIMSELF TO THE A.R.H. CLINIC IN HAZARD - X-RAYS.