PS 83-223
Screening of horticultural plants for phytoremediation of aged motor oil in soil

Friday, August 15, 2014
Exhibit Hall, Sacramento Convention Center
Alexandria Igwe, Texas A&M
A. P. Schwab, Texas A&M
Frances Whitehead, School of the Art Institute of Chicago
Background/Question/Methods:

The purpose of this project was to utilize a whole-system approach to plant-based remediation in which a purely engineered perspective to remediation was replaced with a more sustainable and comprehensive approach. Our goal was to reach beyond hydrocarbon phytoremediation science and employ a land use typology that positively impacted human and animal communities. These goals were met by conducting a greenhouse experiment and complementary field trial of plants to test the dissipation of petroleum and assess plant vigor and adaptability in the contaminated soil. In the greenhouse, 80 plant species were grown in soils treated with motor oil representing total petroleum hydrocarbon (TPH) to a final concentration of 4000mg TPH/kg soil. After seven months, the pots were sacrificed and residual TPH was quantified. In the field, an experimental site soil preparation method was used in conjunction with a radial site design that exploited the variation in temporal bloom of the plants and separated them according to relevant biotic community divisions such as shading, perennial or fruiting. 

Results/Conclusions:

Overall, twelve species were found to enhance petroleum dissipation when compared to natural attenuation in the greenhouse experiment. In the presence of the twelve species, TPH dissipation was at least 50%, and Purple Coneflower and Blue Giant Hyssop removed 71.1% and 72.5% of TPH, respectively. Partnerships with the community were initiated and continued past project completion and one of Chicago’s abandoned service stations was transformed into a community laboratory garden that integrated aesthetics and passive economic benefit while providing greenspace to the city.