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REV: 10-05-2022 VR <br />A total of 278 temporary injection points shall be advanced using direct-push <br />technology to a depth of approximately 18 ft bgs; <br />Delivery point spacing shall be 12 to 14 ft on center; <br />Sequential rows of EVO delivery points shall be offset (odd vs even) to <br />produce a zig-zag pattern; <br />The emplaced thickness will be approximately 12.0 ft; injecting at 2-ft <br />intervals; and <br />The treatment surface area shall encompass approximately 11,250 ft2. <br />The orientation and placement of proposed injection point locations shall be <br />slightly adjusted by the Consultant to accommodate existing structures such <br />as monitoring wells, curb dividers, medians and landscape islands while <br />preserving the zig-zag pattern. Exact injection point locations shall be <br />reviewed and approved by the Public Works Director or designee before <br />injection. <br />Approximately 28 gallons of EVO shall be injected at each DPT push point, <br />totaling 7,784 gallons of EVO, injected through 278 injection points. <br />Consultant has selected and estimates the injection rate for each individual <br />injection point to range between 3 and 5 gpm. EVO injection shall require an <br />estimated initiation pressure between 70 and 90 psi, with a target <br />maintenance injection pressure of 65 to 75 psi. Consultant shall adjust <br />injection volumes based on actual injection rates achieved in the field. <br />1.3.3. Drilling and Delivery Specifications - The ZVI/EVO or EVO only injection points <br />shall be installed by a direct push drill rig. Consultant shall use a drill rig to <br />advance 1.5-inch direct-push rods equipped with an injection tip through the pre- <br />cleared borehole location. Injection shall commence in 2 ft vertical intervals over <br />an approximate 12-ft vertical injection span to the prescribed total depth and <br />working in a ‘top down’ sequence. <br />Consultant shall select a drill rig that will successfully inject the ZVI/EVO into the <br />subsurface. Consultant shall use flow meters and pressure gauges to control <br />injection volume and pressures, make every effort to minimize daylighting of <br />reagents, and measure groundwater from monitoring wells during injections. <br />Based on injection point feedback, targeted injection depths, reported ZVI/EVO <br />volume and pressures, the Consultant shall calculate and field verify the targeted <br />radius of influence and distribution of injectant. <br />1.4. “E” Wells Area: Enhanced Reductive Bioremediation (ERB) <br />The “E” Wells Area is indicated in Exhibit C. Temporary injection points (direct push <br />probes) shall be advanced by Consultant in rows of treatment nodes approximately <br />perpendicular to the inferred direction of contaminant transport. Technical information <br />required to execute full-scale remediation is summarized in Exhibit D (Tables 1 and 2). <br />Consultant shall injecting using Terra System’s SRS-SD® EVO. EVO shall be mixed <br />with water for fluidization. <br />1.4.1. Injection Point Design and Layout – Consultant shall inject EVO mixture into the <br />chlorinated solvent plume within the “E” Wells Area according to the following <br />specifications: <br />ATTY/AGR.2022.348/Regenesis Bioremediation Products (Page 17 of 34)