Comprehensive assessment of the effectiveness of remediation of petroleum-contaminated soils following an accidental oil spill

This paper presents the results of a comprehensive assessment of the effectiveness of remediating soils contaminated with light petroleum products following the destruction of fuel storage tanks at an oil depot in the urban-type settlement of Borodianka, Kyiv Region, Ukraine, during military operations. The study employed an integrated methodology combining field hydrogeological investigations, mathematical modeling of contaminant migration within the vadose zone, laboratory analyses, and an experimental evaluation of an integrated remediation technology consisting of free-phase petroleum product recovery, decantation, and vacuum distillation. The remediation performance was quantitatively evaluated using a set of integrated indicators, including the contamination reduction coefficient, residual contamination coefficient, environmental hazard reduction coefficient, integrated potential migration hazard index, and the mass balance of recovered petroleum products. The proposed remediation technology reduced the average concentration of petroleum hydrocarbons in soil from 43,640 mg kg−1 to 2,180 mg kg−1, corresponding to an overall remediation efficiency of 95%. The overall contamination reduction coefficient reached 20.0, whereas the decantation and vacuum distillation stage alone achieved a reduction coefficient of 8.61. The calculated environmental hazard reduction coefficient indicates a substantial decrease in the risk of secondary contamination of both soils and groundwater. These findings demonstrate the effectiveness of the integrated remediation approach for mitigating the environmental consequences of accidental petroleum spills and provide a scientific basis for the development of technological guidelines for the reclamation of petroleum-contaminated sites.