HE WAS PERFORMING A SECONDARY BLAST ON A ROCK (25-30 TONS). WHILE STANDING ON TOP OF THE ROCK, HE LOADED THE CHARGE AND LIT IT. WHILE STANDING UP TO EXIT THE ROCK, HE SLIPPED AND FELL OFF THE ROCK. HE LANDED ON HIS LEFT SIDE ON THE CLOSED TAILGATE OF THE PICK UP TRUCK. HE RECEIVED SEVERE CONTUSIONS AND MUSCULAR STRAIN TO HIS LEFT RIBS, SIDE AND BACK.