| Abstract: | Global climate changes can lead to the destruction of the permafrost zoneand contribute to the active transfer of pollutants to natural waters. Thiscan be especially pronounced in the areas of oil and gas production in theArctic. This study aimed to define the landscape components (i.e., groundwater, soil water, soil, and indicator plant species) of chemical pollution with metals, oil hydrocarbons, and polycyclic aromatic hydrocarbons, from the discharge of drill cuttings. Studies at two sites in the forest-tundra zoneof Western Siberia (Russia) were carried out within two years of pollution. Pollutant migration was found in peaty-gley heavy loamy soils andiron-illuvial clayey podburs, but lateral migration of different pollutantsdid not exceed 200 m. Additionally, radial migration was practically absentowing to the high buffering capacity of the soil organic horizon and theupward flow of matter in the seasonal melt layer. The main indicators ofdrilling waste pollution were high concentrations of Sr, Ba, petroleumhydrocarbons, and Cl- ions. At the waste disposal sites, theconcentration of Ba and Sr in the soil water were 1 150 and 1 410 μgL-1, respectively; in groundwater, they reached 721 and 2 360 μgL-1, respectively. In the soil, Ba and Sr accumulated in the peatyhorizon (798 and 706 mg kg-1, respectively). The concentration ofCl- ions in the soil water at the site of waste discharge was 1 912 mgL-1, and at a distance of 200 m, it decreased to 77.4 mg L-1. TheCl- concentration in the groundwater was lower, and at a distance of200 m, it was 38.9 mg L-1. The highest concentration of petroleumhydrocarbons in the surface layer was found in the peaty-gley soils (up to 2 400 mg kg-1). In glandular-illuvial podburs, it was 420 mg kg-1. In horizons BH and BC, it was close to the background values (27 and 33 mgkg-1, respectively). Alkalinization of soils and water under theinfluence of drill cuttings led to the death of oligotrophic and acidophilicvegetation at a distance of up to 50 m, and to the restructuring of thespecies and spatial structure of plant communities up to 100 m. |
