Phytoremediation, Part II: Management Considerations

Abstract

Environmental regulators and other stakeholders prefer cleanup technologies that are successful, cost effective, and not disruptive to a site. Phytoremediation offers an appealing in situ option to managers of remediation projects. Remediation project managers and teams must be experienced and work closely together. For moderately water soluble organic contaminates, it may be possible to utilize plant species that can translocate and metabolize a contaminant within their shoots. For highly lipophilic compounds, a phytoremediation strategy would best focus on stimulation of biodegradation within the root zone of plants. Metal hyperaccumulator plant species have demonstrated successful growth under high enrichments of specific metals. However, while there is promise for hyperaccumulators concentrating metals, their low biomass suggests total uptake may be low. Genetic manipulations of potential plants may possibly overcome this difficulty, but there are inherent societal concerns and risks. Matrix manipulation may enhance phytoremediation by improving the availability of metals, but care must be taken to not impair plant growth and prevent off-site migration of metals. A thorough site characterization is required to properly design a strategy. Costs associated with phytoremediation are competitive with other remediation technologies and cost recovery can be realized when metals have a high enough value to be recycled following harvesting from the plant biomass.