Radial Migration of Petroleum Hydrocarbons in Soils of Sakhalin Island by Data of Laboratory Lysimetric Experiments

The radial migration of total petroleum hydrocarbons (TPH) in soil and their inflow into lysimetric leachates have been estimated to determine the permissible residual content of TPH (PRCTPH) in the main soil types of Sakhalin Island. The maximal concentrations of TPH, of their medium- and high-boiling fractions in particular, are allocated to peat and humus horizons, as well as to soil horizons of heavy loamy granulometric composition, which represent radial geochemical barriers for migrating pollutants. Benzene and its homologues are detected in filtrates from soil lysimeters after the percolation of water in the amount of three-quarters of the annual precipitation. After the filtration of the water amount equal to the annual precipitation, these compounds are not revealed. The toxicity of leachates has been assessed by bioassay, using ceriodaphnia and ciliates. The PRCTPH in soils with respect to the water migration index may be determined by the concentration of TPH and the content of monoaromatic compounds in leachates and their toxicity for hydrobionts in lysimetric experiments.