In situ bioremediation of subsurface petroleum contamination in Western Canada

Bioremediation is an emerging technology that helps clean up soil and groundwater, which are contaminated with petroleum products. This study investigates the bioremediation of petroleum-contaminated subsurface in a western Canadian context. Screening and enhancement of gasoline degradable local psychrophilic microorganism strains are conducted for the soil samples acquired from petroleum-contaminated sites and yard compost. Four purified strains obtained through the process are applied in batch experiments to determine their performance under various conditions. A factorial design is then conducted with four factors (nutrient richness, inoculation amount, temperature, clay/silt content) at two levels. The results show that clay/silt has the highest negative effect on degradability of the microorganism followed by temperature with positive effect. Validation of these results is being processed in a pilot-scale physical model and on a practical site with one- and six-month experimentation periods, respectively.