THE INJURED EMPLOYEE AND CO-WORKER WEREIN THE PROCESS OR REPAIRING A D11 DOZER THAT HAD BROKEN DOWN IN #2 PIT. A FINAL DRIVE WAS BROUGHT IN BY FLATBED TRAILER. USING A BOOM TRUCK, THE FINAL DR IVE WAS REMOVED, POSITIONED AT THE END OF THE TRAILER, AND BLOCKED TO PREVENT SIDE-TO-SIDE MOTION. AS THE CO-WORKER STEPPED OFF, HE FELL TO THE GROUND, LANDING IN UNEVEN AREA.