Adsorption and degradation of PAH compounds in soil. Progress report. [Acenaphthene, naphthalene]

Organic contaminant fate in soil/water systems can be affected by the biological characteristics of the soil and of the pollutant. This work investigates biodegradation of polycyclic aromatic hydrocarbons (PAH) in a soil environment under denitrification conditions. The objectives of the work over the past quarter were to compile and assess literature related to biological degradation of PAH under denitrification conditions, and to perform experiments to verify PAH degradation under denitrification conditions. Information from the literature is being utilized to develop a model to describe organic substrate usage when PAH is discharged into soil/water environments devoid of oxygen. An important concept which will be incorporated into the model is that PAH competes with other naturally occurring organic carbon sources as a substrate for biological metabolism in soil/water systems. Experiments were conducted to examine the degradation of naphthalene and acenaphthene under denitrification conditions. Several tests were also performed to examine denitrification without the presence of PAH to assess the contribution of available soil carbon as an organic carbon substrate. Results are discussed. 10 refs., 12 figs.