Sources of polycyclic aromatic hydrocarbons in sediments of the Kinnickinnic River, Wisconsin

A chemical mass balance (CMB) model was developed and used to apportion both point and nonpoint sources of polycyclic aromatic hydrocarbons (PAHs) in six dated sediment cores. The cores were collected in 1994 from a stretch of the Kinnickinnic River between The Becher Street Bridge and the Wisconsin Wrecking Company Wharf, Milwaukee, Wisconsin, and had PAH concentrations of 80 to 1,000 ppm. This work was done in order to identify major PAH sources to this IJC Area of Concern which is important for pollution modeling and management. The source fingerprints were taken from the literature. Coke oven emissions and coal-wood gasification or coal tar are the main local PAH sources, whereas highway dust provides an important nonpoint input since the 1920s. Coal-wood gasification ceases to be a significant source after 1950-'60. Factor analysis based on nonnegative constraint of factor scores and loadings, and oblique rotations, supports this apportionment, but points also to deficiencies in the CMB source profile for coke oven emissions. It appears that the now defunct Milwaukee Solvay Coke Co. was a major source, The influence of geophysical factors and chemical and biological fractionation of the selected PAH compounds appears to be small.