Bioremediation

In December 2016, an orphan well spilled oil next to the Tionesta Creek in Warren County. There were no state resources available for the cleanup of the spill site. A PGCC member volunteered to provide the equipment, manpower, and supplies to plug the well.

For the cleanup, the PGCC member and the DEP partnered to test cleanup via bioremediation. Bioremediation is a natural attenuation mechanism. In layman’s terms, microbes found naturally in the soil use the paraffin-based oil as a food source; the digestion process breaks down the oil. Although common in other states, bioremediation is not regularly used in DEP monitored oil cleanup in Pennsylvania. However, the EPA has regularly 

Describe your image

press to zoom

Describe your image

press to zoom

Describe your image

press to zoom
1/2

employed bioremediation in the oil cleanup projects it monitors in northwestern PA. The EPA has published several papers about the success of its efforts. To learn about bioremediation, PGCC sponsored two seminars; the first by Dr. Kerry Sublette, Professor of Chemical Engineering at the University of Tulsa, OK, and the second by Vincent Zenone, OSC, U.S. Environmental Protection Agency. Both seminars were well attended by DEP staff and the seminars successfully brought about a greater understanding of the function and potential of bioremediation.

A “biopod” was constructed at the spill site, and the oil and contaminated soil were placed in the biopod. The oil, contaminated soil, and vegetative material were cultivated.

Commencing in the 2017 growing season, PGCC’s member regularly cultivated the biopod, occasionally adding lime and vegetative matter. Regular testing has been conducted with impressive results. Before biopod construction, the total petroleum hydrocarbons (TPH) found naturally in the soil were slightly less than 1000 mg/kg. After construction of the biopod, the TPH shot up to 140,000 mg/kg. Since then the TPH has steadily declined. By June 2017, it was cut in half to about 60,000 mg/kg. By August, it was cut in half again to slightly under 30,000 mg/kg. The EPA considers 10,000 mg/kg to be a satisfactory outcome. By August 2018, the TPH was reduced to 1900 (5 times lower than the EPA satisfactory level).

bio3.png