Project 1: Sustainable Remediation

Principal Investigators: Jodi R. Shann and Steven Rogstad (University of Cincinnati)

Collaborator: Chevron Products Company

The goal of the proposed research is to determine if natural revegetation and community succession is an effective and sustainable means of stabilizing and remediating sites contaminated with polycyclic aromatic hydrocarbons (PAHs) and metals. An extension of this objective is to measure the degree to which the community that develops through revegetation is similar (in either form or function) to those in local, uncontaminated areas. The current approach to in situ remediation using plants involves labor-intensive site preparation, planting, and maintenance of the system by replanting, watering, fertilizing, and controlling pests. Though these activities may be less expensive than many traditional cleanup strategies, they are not necessarily cheap or sustainable over the increased duration needed to achieve acceptable remediation. Many of the above costs and uncertainties could be avoided by allowing sites to naturally revegetate via plant and seed immigration from surrounding (edge) communities. Revegetation by natural processes would eliminate planting costs, and would better ensure the success of plants, as they would only persist in areas with conditions that support their growth. Subsequent succession of the plant community across the site would likely lead to a self-sustaining system of increasing compositional and, perhaps, functional biodiversity. Natural revegetation results in effective soil cleanup and leads to a community that looks and functions in a fashion similar to others in the vicinity, the outcome would be both site remediation and ecological restoration. Therefore, we propose to monitor the establishment and succession of natural plant communities on a closed field site contaminated with PAHs and metals. While following the revegetation rate and pattern, we will simultaneously determine the effectiveness of the vegetation on the remediation of the site.