An Integrated Multi-component Phytoremediation System for Removal of Polycyclic Aromatic Hydrocarbon Contaminants from Soil

A number of techniques, both mechanical and biological, have been investigated for the remediation of persistent organic contaminants from soils. However, most of these techniques have been applied independently. As a consequence of using only one process, remediation usually is slow for persistent organic contaminants. To improve remediation, a few techniques that complement different aspects of contaminant removal have been applied to soils in combination resulting in an enhanced multi-process phytoremediation system. This multi-process system has greatly improved and accelerated the overall remediation process resulting in removal of 95% of total PAHs. The remediation system includes: physical (volatilization), photochemical (photooxidation), microbial degradation and plant growth (phytoremediation) processes. The techniques applied to realize these processes are land farming (aeration and light exposure), microbial remediation (introduction of contaminant degrading bacteria) and phytoremediation (plant growth with plant growth promoting rhizobacteria). This system was very effective at removal of persistent soil bound contaminants from soil. It appears that the combination of these components may be a viable solution for remediating persistent organic contaminants from soils.