Phytoremediation: Plant-Based Remediation of Contaminated Soils and Sediments

The plant-based remediation methods for dredged material slurries and metal-contaminated soils have been proposed since the mid seventies. This chapter discusses plant-based remediation of contaminated soils and sediments. All in-situ site remediation programs follow either a contaminant containment or contaminant reduction strategy. Phytoremediation is an emerging technology that promises a viable remediation when pollutants are near the surface, are relatively nonleachable, and pose little imminent risk to health or the environment. It is useful to visualize and describe a plant in engineering terms in order to shift the familiar agronomic plant paradigm and to clarify the concept of phytoremediation to those professionals who are more familiar with engineering terminology. At a basic level, green plants are solar-driven pumping and filtering systems that have inherent loading, degradative, and fouling capacities. The coupling of hyperaccumulation of metals and sequestration of organics with larger biomass and potentially deeper rooting systems may result in powerful phytoremediation technology.