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Gealagiest reduacs Inc. Page 3 <br /> ' IRAP-Pilot Test <br /> Project No. 425.2 <br /> March 21,2005 <br /> ' GTI anticipates proceeding with the pilot testing of ozone sparging with a vapor extraction <br /> system as explained in the following sections. <br /> 2.0 IN-SITU CHEMICAL OXIDATION/OZONE SPARGING <br /> ' 2.1 Technology Review <br /> The process of in situ chemical oxidation has been used successfully in many applications. <br /> ' Advanced Oxidation Processes (AOPs) are processes that create and use a highly reactive <br /> radical that effectively oxidizes organic compounds by chemical reaction. The most <br /> prominently used radical is the hydroxyl radical, designated as OH. The OH ion will <br /> capture a hydrogen atom from a molecule of contaminant, which then causes the contaminant <br /> molecule to become unstable and breakdown. <br /> The AOPs have been very successful at treating gasoline compounds and the gasoline <br /> oxygenated fuel compounds. AOPs are promising because they quickly destroy the <br /> contaminant rather than just augmenting the relatively slow biological processes at the site. It <br /> ' is noted that a byproduct of injecting oxidizing agents is an increase in the oxygen content of <br /> the subsurface to promote biodegradation rates. <br /> ' The basic chemistry of reduction-oxidation (Redox) reactions is a combination of chemical <br /> reactions (changes in chemical bonding) and the transfer of electrons. A more detailed <br /> explanation is: specific bonds are broken while others are formed when a donor gives up an <br /> electron (e) and a receptor acquires the e-. In the case of petroleum contamination, BTEX <br /> and TPH-G are reduced (gain of electrons and a decrease in valence) and in an aerobic <br /> environment oxygen is oxidized (loss of electrons and increase in valence). In an anaerobic <br /> ' environment, oxygen has been depleted by this reaction and mineral compounds, such as <br /> MnOZ,NO3, Fe(0)3, SO4 and H+, become the a donor (listed in decreasing Eh values). <br /> tThe following Table lists the common Redox potential and relative oxidizing power of the 1 <br /> primary oxidants. According to the RWQCB, injection of ozone, peroxide and oxygen are 4 V <br /> ' acceptable agents to use without needing a waste discharge requirement permit. GTI <br /> proposes using ozone to destroy petroleum hydrocarbons. <br /> 1 <br /> 1 <br />