ABSTRACT
Because of the many shortcomings of current remediation alternatives, there is a growing need for the development of alternative technologies that are low cost, low input, and environmentally benign, yet provide equivalent protection to human health and the environment. Many innovative remediation techniques being currently developed focus on exploiting or altering the soil chemistry to either remove contaminants from the soil or reduce their solubility and bioavailability while leaving them in the soil. Some of the more promising innovative remediation alternatives include plant-based or "phytoremediation" techniques such as phytoextraction and phytostabilization (i.e. inplace inactivation). In phytoextraction, the contaminant is gradually removed from the soil by plant uptake and harvesting (or, in the case of mercury, by volatilization). Conversely, inplace inactivation is a site-stabilization technique in which materials are applied to the soil to alter the soil contaminant chemistry, making the contaminant less water-soluble, less mobile, and less bioavailable. Inplace inactivation does not affect the total contaminant concentration, but reduces the risk of harm to a target organism (e.g. humans) making the contaminant unable to biologically interact with the organism. Inplace inactivation is based on fundamental soil chemistry, plant biology, agricultural practices, and experience with the restoration of drastically disturbed mine and roadside lands and construction sites. Inplace inactivation appears to be a relatively simple, low-cost, low-input method, and should prove adaptable to a wide range of contaminated sites.
