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Soil Boring Results and VEG/ISCO Work Plan Field Maintenance Shop #24, Stockton, California October 2016 applicable VEG and ISCO boring permits will be obtained from the San Joaquin County Environmental Health Department (SJCEHD) prior to conducting any drilling activities. In addition, applicable air quality permits or exemptions will be obtained from the San Joaquin Valley Air Pollution Control District (Valley Air District) prior to the field implementation of the work plan. 3.2. Vapor Energy Generator Technology The Vapor Energy Generator (VEG) soil remediation technology, developed and patented by Endpoint Consulting, Inc. is a closed-loop thermal treatment process that uses high temperature steam with patented emission-reducing filters to treat contaminated soils. VEG technology can be performed both ex-situ and in-situ. The ex-situ component of the VEG technology utilizes a mobile, fully enclosed soil remediation system capable of thermally treating petroleum hydrocarbons, chlorinated solvents, munitions constituents, pesticides, PCBs, PFCs, and select metals (including arsenic, mercury, zinc) in soils. The ex-situ component of the VEG technology has been used successfully to consistently treat a full range of organic compounds (including petroleum hydrocarbons present at the Site) and select metals to non-detect levels (i.e., 99.99% reduction) in soils within a few minutes of treatment time, corresponding to typical treatment rates of 300 cubic yards per day. The ex-site option requires excavation of soils for onsite treatment, followed by backfilling of the excavation with the treated soils, with no restrictions on land use. Due to the depth of soil impacts, utility conflicts and impacts to CA ARNG facility operations implementation of ex-situ VEG was not considered reasonable at the Site. The in-situ component of the VEG technology relies on the vapor generator as a highly efficient and cost-effective source of thermal energy used for heating the subsurface, and thereby changing the physical properties of the aforementioned contaminants in soils. Induced vapors from in-situ application are recovered through recycling. Recovered vapors are removed via soil vapor extraction, with the effluent routed through a series of patented filters for treatment via chemical reduction, thermal oxidation, and transformation into syngas, with acidic gases such as mono-nitrogen oxides (N0x), sulfur oxides (S0x), hydrogen chloride (NCI), and hydrofluoric acids eliminated from the vapor stream through interaction with caustic soda. Carbon dioxide (CO2) reduction also occurs through application of a patented treatment process involving the use of water and lime, with the resulting hot vapor stream routed back to the injection wells for continued in-situ treatment. The patented filters and the closed-loop nature of the treatment process ensures elimination of air emissions, thereby easing the air quality permitting process. The in-situ component of the VEG technology has been used to achieve chemical concentration reductions ranging from 85% to 99.99% (with typical reductions on the order of 90%). In-situ VEG requires heating of the subsurface for periods on the order of 2 to 3 weeks, and extraction of induced vapors for at least a one-week period. Therefore, treatment durations using the in-situ options are greater than those for ex-situ treatment, but the former eliminates the need for excavation of deep soils and has been selected by the CA ARNG for treatment of residual hydrocarbons present at depths of 15 to 35 feet bgs. The VEG treatment area is located in the vicinity of FMS-MW6 (Figure 6). 3.2.1. VEG Implementation Objectives Based on the recent and historical soil analytical data discussed in Section 2.0 above, the CA ARNG and its contractor propose to perform a small scale in-situ thermal treatment of vadose zone soils utilizing VEG technology. The treatment area is approximately 400 square feet centered around FMS-MW6 (Figure 6), with a vertical treatment interval ranging from 15 to 35 feet bgs. Page 6.