This study investigated the potential for Phase 2 mushroom compost to degrade phenanthrene (a representative PAH) in both slurry and soil systems. Initially, induction of catabolic ability within the compost was assessed after increasing compost-phenanthrene contact times. This was achieved by monitoring the evolution of (CO2)-C-14 from the mineralization of freshly added C-14-9-phenanthrene to aqueous compost slurries in respirometers. A subsequent experiment to assess the potential of the compost to bioremediate aged phenanthrene (300 d) from soil was then conducted in aerated microcosms. The extent of mineralization using induced compost was compared to that where uninduced and no compost was used. The results suggested that with increasing compost-phenanthrene contact time there was an increase in catabolic capability. Initial, (0 d compost-phenanthrene contact time) mineralization was less than 2%. However after 7 weeks compost-phenanthrene contact time greater that 65% mineralization was observed. When remediation of aged phenanthrene from soil was attempted the induced compost produced the greatest extent of mineralization initially. However, after 21 d remediation time the cumulative extents of mineralization were similar in all microcosms.
5th International In Situ and On-Site Bioremediation Symposium, SAN DIEGO, CA, APR 19-22, 1999