EMPLOYEE WAS WAITING IN HIS TRUCK AT THE PRIMARY CRUSHER. AS PART OF THEIR JOB, THEY ARE TO REMOVE ANY SMALL ROCKS FROM ROADWAY TO PREVENT TIRE DAMAGE. HE HAD A FREE MOMENT AND DECIDED TO MOVE SOME ROCKS. EMPLOYEE HAD REMOVED SEVERAL STONES WHEN THE LAST ONE CAUSED A STRAIN IN HIS RIGHT FOREARM. THERE WAS MINIMAL LIFTING BUT MOSTLY LATERAL MOVEMENT.