SUPERVISOR TRIED TO USE 12 GAUGE SHOTGUN TO DISLOGE A PLUG IN T AIR DUCT ON PREHEATER TOWER. HE FIRED GUN @ POINT BLANK RANGE @ THE PLUG. THE SLUG SHATTERED & SMALL PIECES OF LEAD HIT HIM ON R IGHT THUMB & FOREARM. HE WAS SENT TO ER FOR TREATMENT. THEY CLEANED & DRESSED THE WOUNDS - THERE WERE NO SUTURES.