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Chlorinated VOC treatment by ozone and hydrogen peroxide is well documented and as a result, chemical oxidation is considered a technically feasible technology for mitigation of the groundwater impacts identified at the CHSL, but the chemical oxidation reactors typically used to treat VOC-impacted water are extremely expensive and more complex when compared to other equally-effective ex-situ treatment technologies. As a result, although technically feasible, this alternative is considered not viable and will not be considered for further analysis. Above-ground Metal Enhanced Reductive Dehalogenation (MERD) Reactor: Not Viable—This technology is similar to the in-situ MERD technology in that the extracted groundwater is passed through above-ground reactive vessels that contain iron shavings. Degradation of chlorinated VOCs is then accomplished in a fashion similar to the in-situ MERD technology (Section 3.5.1). Data from field tests indicate that this technology may be as effective as air stripping and GAC technologies in removing select halogenated VOCs from groundwater; however, the available data do not support the use of MERD to reduce VOC concentrations lower than those measured in groundwater samples collected at the CHSL. For this reason, MERD reactor technology is considered not viable for mitigation of the low concentrations of VOCs identified at the CHSL. • Reverse Osmosis: Not Viable — This technology is appropriate to treat groundwater contaminated by inorganic constituents such as TDS, chloride, and nitrates. Water is forced through a semi-permeable membrane, producing a clean effluent and a "reject" stream (brine) that contains high concentrations of the inorganic contaminant. The reject stream is then trucked off site or placed in an evaporator pond for disposal. While this technology is considered an effective means of treating inorganic compounds in groundwater, the technology is considered not viable for treatment of organic contaminants at the CHSL. Ion Exchange: Not Viable - This technology also addresses elevated concentrations of inorganic constituents such as TDS, chloride and nitrates. Water passes over a series of resin columns where contaminants are bound by adsorption processes. Thus, the process produces a clean effluent. As the adsorption sites on the resin media become saturated, the resin must undergo a regeneration process using a strong acid and base solution. This produces a "reject" stream that contains high concentrations of brine. The reject stream is then trucked off site or placed in an evaporator pond for disposal. • Engineering Feasibility Study Geo-Lo Page ■ 20 Corral Hollow Sanitary Landfill A S S O C I A T E Sg January 25,2013