The Site 4 plant treats 11 to 12 MGD of wastewater from domestic (80% of influent) and industrial (20% of influent) sources. The treated primary/secondary sludge is dewatered using cloth filter presses to approximately 35 percent solids. The dried filter cakes are incinerated in a six-hearth unit and emissions are controlled with an afterburner, a precooler, a water injection venturi, and tray scrubber. Tests were conducted to determine particulate, metals, and organic emissions at the control device inlet and outlet sampling locations. Under normal operating conditions, the most prominent metal at the scrubber inlet flue gas stream was lead while zinc had the highest concentrations at the flue gas outlet. Of the target volatile organics, acrylonitrile and acetonitrile were detected in the highest concentrations. The venturi/tray scrubber showed 40 percent removal of acrylonitrile, chlorobenzene, and ethylbenzene. The following compounds appeared to be stripped from the scrubbing liquor into the flue gas: carbon tetrachloride, chloroform, methylene chloride, tetrachloroethene, toluene, 1,1,1-trichloroethane and trichloroethene. Three of the target volatile compounds (acetonitrile, acrylonitrile and benzene) were products of incomplete combustion (PICs) regardless of incinerator conditions. Semi-volatile organic compounds were tested only at the incinerator exit. Testing revealed phenol and naphthalene as the only compounds present. Dioxin/furan tests indicate average 2378-TCDD emission rates of 1.45 microgram/hr during cool furnace tests and 0.35 microgram/hr during hot furnace tests.