THE EE WAS PUSHING A WHEEL BARREL LOADED WITH 4 BAGS OF ROCK DUST DOWN THE BELT LINE. THE AREA WAS WET, THE EE STEPPED IN A HOLE AND THE WHEEL BARREL STARTED TO TIP OVER. THE EE TRIED TO STRAI GHTEN THE WHEEL BARREL AND AT THIS TIME HE FELT A PAIN IN THE LOWER LEFT AREA OF HIS BACK AND LEG. EX-RAY NEGATIVE, STRAIN.