Characterization of Petroleum Fractions and Ecotoxicity as a Science-Based Framework for Bioremediation Applications

Hydrocarbon-contaminated sites are among the most common challenges for environmental professionals worldwide. Although bioremediation strategies have emerged, their efficiency in cleaning hydrocarbon-contaminated soil depends considerably on local conditions. This study presents a science-based framework to assess the potential for soil bioremediation based on site-specific conditions. At multiple depths, soil samples were collected from four locations (S1, S7, S13, and S16) within a historically contaminated heating plant site. Using a three-step framework based on the content of total petroleum hydrocarbons (TPH), hydrocarbon pollutant fractions, ecotoxicity, and microbial population density, the study quantitatively (using a scoring matrix) revealed considerable variability across locations regarding the potential for bioremediation. Thus, due to balanced parameter contributions, S16 has the most promising bioremediation potential. Location S1 may require additional effort to enhance microbial populations. Locations S7 and S13 have low scores, with S13 being the least suitable, requiring extensive efforts to improve site-specific conditions for bioremediation. By integrating chemical, biological, and ecological factors, this science-based framework emphasizes the importance of site pre-characterization, thus providing an evaluation tool for bioremediation applications at hydrocarbon-contaminated sites with similar data availability. Moreover, the pre-remediation matrix scoring evaluation results align with the in situ bioremediation efficiency observed at the site.