Agronomic Optimization for Phytoremediation of Polycyclic Aromatic HydrocarbonsEPA Grant Number: R831072
Title: Agronomic Optimization for Phytoremediation of Polycyclic Aromatic Hydrocarbons
Investigators: Nedunuri, Krishnakumar , Lowell, Cadance , Okunade, Samuel
Institution: Central State University
EPA Project Officer: Hahn, Intaek
Project Period: October 1, 2003 through March 31, 2006 (Extended to June 30, 2006)
Project Amount: $336,649
RFA: Superfund Minority Institutions Program: Hazardous Substance Research (2002) RFA Text | Recipients Lists
Research Category: Hazardous Waste/Remediation , Land and Waste Management , Safer Chemicals
Phytoremediation is a low-cost method of using plants to degrade, volatilize or sequester organic and metal pollutants that has been used in efforts to remediate sites contaminated with polycyclic aromatic hydrocarbon (PAH) refinery wastes. Non-native plant species aggressively degrade contaminants, and support large biomass. However, these plants must be carefully managed, requiring frequent irrigation and fertilization. And, non-native plant species cannot restore the natural ecosystem. These non-native species may actually disturb natural plant succession in polluted sites. Allowing native species to naturally revegetate is an attractive proposition since it saves on the cost of restoration and management. Optimization of agronomic practices at refinery waste disposal sites undergoing such plant-based remediation methods is essential for managing site remediation efforts. This proposal is an innovative effort to optimize these practices critical to cleaning up PAHs from refinery waste disposal sites using native plant species.
The research involves three major tasks: 1) greenhouse studies to investigate agronomic practices -- composting, NPK fertilization and irrigation -- on PAH reduction in PAH contaminated soil planted with native grass species; 2) greenhouse studies that compare PAH reduction in soils from contaminated sites in managed and non-managed containers planted with heterogeneous planting of a mixture of three native grasses to mimic succession; and 3) field-scale demonstration of best agronomic practices applied on PAH contaminated soils in Ohio undergoing treatment in the presence of native species and modeling of PAH degradation and species productivity, incorporating spatial and temporal heterogeneities and integrated variance inherent at field-scale in soils.
This study will be first of its kind to arrive at the best combination of agronomic practices critical to the success of phytoremediation. These practices catalyze otherwise slow natural revegetation/managed systems, in terms of increasing biomass productivity and perhaps concomitant accelerated degradation of contamination. These studies will also evaluate the effectiveness of allowing natural succession of plant communities to establish over contaminated sites, over the introduced targeted species for phytoremediation. The research should provide important clues to achieving holistic remediation that includes both clean up of disturbed sites as well as their ecological restoration.