Biobarrier stability lab-scale studies for treatment of hydrocarbon- contaminated groundwater

The stability of a laboratory-scale bioreactive barrier in the treatment of contaminated ground- water was evaluated over a 16 month operation. Simulated groundwater contained diesel as the source of total petroleum hydrocarbons (TPH), and selected metals, as found at a North-Quebec site. Two 5-L capacity bar- rier prototypes, packed with peat moss granules and inoculated, were operated at 10 o C. The biobarrier showed a TPH removal efficiency varying between 70 and 97%, depending on the TPH load. Sorption of TPH onto peat contributed to the TPH removal; however microbial biodegradation was the ultimate mecha- nism of TPH removal as shown by the biomineralization of chemical models: over 62% for hexadecane and 88% for naphthalene. Biomass enriched relatively rapidly in hydrocarbon-degrading microbial populations.