Ex Situ Bioremediation of Polycyclic Aromatic Hydrocarbon Contaminated Soil Using a Static Aeration Biopile Process

A static aeration biopile process was used to bioremediate polycyclic aromatic hydrocarbon (PAH)-contaminated soil using four different approaches for treating about 30 m3 of soil at a former oil-producing site. The four treatments investigated were as follows: (i) fertilizer plus bulking agent (FB); (ii) fertilizer, bulking agent, plus Tween 80 (FBT); (iii) fertilizer, bulking agent, Tween 80, plus fungi agent (FBTF); and (iv) fertilizer, bulking agent, bacterial inoculum, plus fungi agent (FBBF). After bioremediation for 320 days, the total amount of 16 PAHs ranged from 4.14 to 5.31 mg/kg in the final soil, removal rates ranging from 75.5% to 81.5%. The sum concentration of seven carcinogenic PAHs decreased down to 0.15 mg/kg. The values of the total toxicity equivalence concentrations for 16 PAHs ranged from 0.014 to 0.068 mg/kg. The removal rates of the 16 PAHs in these four different treatments decreased in order FBBF > FBT > FBTF > FB.