The United States Steel Corporation (USSC) Clairton Works consists of a coke plant, chemical plant and steel plant. The facility is in the city of Clairton on the Monongahela River, about 29 km (18 mi) upstream of the confluence of the Ohio, Monongahela and Allegheny Rivers. The major activity at Clairton is the coking of coal and subsequent recovery of chemicals. The steel plant incudes a blast furnace for either basic iron or ferromanganese (FeMn) production and four steel finishing mills. Wastewater is discharged daily into the Monongahela River through outfalls 001, 002, 003, 013, 014, 015, 115, 016, 017 and 018. The remaining outfalls (i.e., 004, 005, 006, 007, 008, 010, 011, 012 and 020) discharge into Peters Creek, a tributary of the Monongahela River. A dye study was conducted on outfalls 003, 004, 008 and 020 by NEIC personnel December 15-18, 1975 to determine if the USSC sampling locations are representative. In-plant monitoring was conducted during January 28-31, 1976. This report summarizes the survey results.