EE WAS RIDING IN THE REAR SEAT OF MANTRIP TRAVELING TO THE MINE AT THE FIRST OF THE SHIFT. AS THE MANTRIP WENT ONTO THE CONCRETE PORTION OF THE CROSSING. THE REAR OF THE MANTRIP BOUNCED OVER T HE TRANSITION FROM GRAVEL TO CONCRETE. THIS CAUSED THE EE TO BOUNCED UP AND STRUCK HIS HEAD ON THE ROOF OF THE MANTRIP COMPARTMENT.