Impact of a semi-industrial coke processing plant in the surrounding surface soil. Part II: PAH content

Topsoil samples taken from different areas of a disused experimental coking plant were analysed in order to determine their polycyclic aromatic hydrocarbon (PAH) concentration. The variation in concentrations as a function of distance from the coking oven battery was studied and a reduction in PAH concentration as the distance to the coking ovensʹ battery increases was observed. Two exceptions are the area in the vicinity of the tar distillation section of the plant, with a strong contribution from high temperature tar, and the area where hot coke was taken out of the ovens, with lower concentrations than expected, as a consequence of the significant presence of coke in the soil. Isomer ratios were calculated, indicating that coal is the source of the PAHs in the soil, but also suggesting an influence of transportation fuels. A comparison of the A horizon samples evidences PAH leaching.