Polycyclic Aromatic Hydrocarbons in Soils of Anthracite Deposit Dumps in Siberia

The contents of 19 priority polycyclic aromatic hydrocarbons (PAHs) have been studied in soils (Spolic Technosols) and parent rocks of dumps at the Gorlovskoe anthracite deposit (Novosibirsk region). The bulk content of polyarenes in the analyzed soils is highly variable: from 100 to 74 622 ng/g. The absence of statistically significant relationships between PAH concentrations and the contents of carbon and physical clay (<0.01 mm) in the studied soils points to the specific processes of PAH formation upon coal transformation in soil-forming dump deposits. These processes produce bitumen lakes on the surface of dumps, in which the concentration of polyarenes may reach 864.4 mg/g. Cluster analysis with the use of the Jaccard similarity index and single-linkage clustering permitted us to group the studied objects according to the organic matter characteristics; the groups with chemogenic transformation of coal particles were distinguished by the Ward’s method. The principal component analysis proved that phenanthrene and 5–6-nucleus compounds have the closest correlation with the first component, whereas the second component correlates reliably with fluoranthene, naphthalene, anthracene, and pyrene. According to our results, the Phe/(Phe + Chr) ratio appears to be the most promising index for evaluating chemical transformation of coal in soils of anthracite deposits.