EMPLOYEE STEPPED OFF EDGE OF 15 INCH HIGH CONCRETE APRON OF PROCESS TRUCK WEIGH SCALE. UPON STEPPING DOWN, HIS LEFT ANKLE TWISTED ON A PIECE OF LIME ROCK. EE FELL AND STRUCK HIS RIGHT SHOULDER ON THE GROUND. HE WAS TRANSPORTED TO THE LOCAL E/R AND TREATED FOR A LEFT ANKLE SPRAIN AND RIGHT SHOULDER CONTUSION.