During the concentration of lead and zinc sulfides from Comirico’s Sullivan Mine at Kimberley, British Columbia, there is also produced an iron sulfide concentrate as a byproduct. A portion of these iron concentrates is roasted and the resulting calcine is treated in electric furnaces to produce 800 tons of pig iron per day. The sulfur dioxide produced in the roasting process is used to make sulfuric acid which is employed in the manufacture of ammonium phosphate fertilizers. Problems in the control of air pollution resulting from the iron sintering, iron smelting, and fertilizer operations at Kimberley are discussed, including those arising as a result of almost continuous expansion of these facilities since their establishment 12 years ago.