Vertical distribution of typical contaminants at a coking plant site, China

Abstract：Eighteen profile samples and one surface sample of the soil at a coking plant site in the southwest of China were collected. Total cyanide, heavy metals, total petroleum hydrocarbons （TPHs） and polycyclic aromatic hydrocar- bons （PAHs） were analyzed by GC-MS and other methods, and distribution of theirs in 0-1 m depth soil profile were discussed. The results show that the areas around coke oven, coke pushing line, coal tar recovery point, mechanization settler, production facility of ammonium sulfate and crude benzol and asphalt conveyor belt of this coking plant are se- verely polluted. The contents of detected total cyanide, TPHs and PAHs in top soils are higher than standard A, which indicates the top soil has been polluted. The contamination in 0.5-1.0 m soil is developed by leaked waste water, de- posited flue gas and waste solids. In bottom soil（ 1.0 m） of some sample points, the higher concentrations of total cya- nide,TPHs,PAHs and benzo[ a] pyrene are influenced by long-term pollution and construction disturbance,where can detect more contamination in deeper soil. Therefore, groundwater remediation should be considered as well as remedial depth of soil during the redevelopment and planning of this area.