In Situ Fenton Oxidation: A Critical Analysis

In-situ Fenton oxidation (ISFO) is a rapidly emerging technology which involves the injection of hydrogen peroxide (H2O2) and other chemical reagents into the subsurface for the purpose of oxidizing and transforming contaminants. ISFO is being applied at an increasing number of sites and may offer some advantages over other remedial technologies. Some of the potential advantages include rapid treatment, applicability to a wide range of contaminants, transformation of contaminants to harmless byproducts, and low cost. However, with any in-situ technology, site specific characteristics and technology application ultimately controls the success of the technology.

During ISFO, numerous reactions occur simultaneously that involve both manmade and naturally occurring parameters associated with the treatment system and can effect oxidation efficiency. A significant amount of heat and O2(g) gas can be released when H2O2 is injected into the subsurface and reacted. In addition to chemical oxidation, other processes occur that effect contaminant fate and transport in subsurface systems. These processes introduce complexity in treatment performance evaluation. Information is presented regarding the fundamental chemistry, bench- and pilot-scale treatability studies, and a critical analysis of the technology including significant fate and transport issues, potential limitations, and recommendations for process optimization and performance evaluation.