Abstract: AT ABOUT 1 PM ON DECEMBER 14, 1986, EMPLOYEES #1 THROUGH #3 WERE CLEANING OUT A POLLUTION CONTROL EQUIPMENT PIT AT A STEEL MILL'S ELECTRIC FURNACE. THE CLEANUP OPERATION HAD BEGUN ON DECEMBER 7TH, WHEN THE FURNACE WENT DOWN FOR MAINTENANCE, AT THE TIME THE EMPLOYEES BEGAN CLEANING THE SLUDGE FROM THE DUCTWORK AT THE SCRUBBER, SLUDGE FELL FROM THE OPPOSITE WALL, STRIKING EMPLOYEES #1 AND #3. ALL WORK IN THE DUCTS WAS THEN HALTED AND THE SLUDGE ACCUMULATION WAS WASHED OFF WITH HIGH PRESSURE WATER HOSES (8,000 PSI). ALL THE SLUDGE IN THE DUCTWORK WAS REMOVED EXCEPT FOR A PIECE APPROXIMATELY 2 FEET SQUARE, WHICH COULD NOT BE BUDGED EVEN AFTER A 2 1/2 HOUR HOSEDOWN. THE TOTAL WASHDOWN TIME WAS APPROXIMATELY 3 1/2 DAYS. THE EMPLOYEES BEGAN CLEANING THE PIT ON DECEMBER TENTH, AND BY THE DATE OF THE ACCIDENT HAD REMOVED ABOUT 18 FEET OF SLUDGE FROM THE PIT (ABOUT 12 FEET SQUARE). THE PREVIOUSLY UNMOVABLE CHUNK OF SLUDGE FELL 55 FEET FOM THE DUCTWORK INTO THE PIT AND STRUCK EMPLOYEE #1 IN THE BACK, KILLING HIM. PIECES OF SLUDGE ALSO STRUCK EMPLOYEES #2 AND #3, SLIGHTLY INJURING THEM. CITATIONS FOR CONFINED SPACE ENTRY WERE RECOMMENDED.