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Geosyntec t Mtstt11alits the center of the first 10-foot injection interval (e.g. if the target interval is 15-25 feet bgs, the rod will be advanced to 24 feet bgs). At the surface,the injection tool will consist of a pressure gauge, a pressure relief valve and provisions to connect to a high-pressure hose for injecting the oxidant. After the target injection volume has been achieved at a specific interval, or if the injection flow rates are less than 2 gallons per minute,the injection rod will be advanced to the next interval and injections will be repeated in this fashion until the target depth is reached. Based on an assumed average porosity of 30%, a volume of 5,000 gallons will need to be injected at each injection interval to achieve the target 10-foot ROL Accordingly,with three target lifts per point, a total of 15,000 gallons is anticipated to be injected per point. In total, approximately 300,000 gallons of 10 g/L KMnO4 is anticipated to be injected in the target injection area,totaling approximately 25,000 pounds (lbs)of KMnO4. To optimize the injection program, a manifold will be used to allow simultaneous injections at multiple locations. The injection manifold will be equipped with dedicated flow meters and pressure gauges to monitor injection parameters at each delivery point. To the extent possible, adjacent locations in the grid will not be injected into simultaneously,to limit interference between injection locations and potential daylighting of injection solution. Nearby monitoring wells will be sealed with rubber sleeves during injection activities to minimize the potential for injection solution to daylight through the monitoring well. During injection, amendment delivery flow rates, pressures, and total volume will be recorded continuously using the instrumentation on the injection rig.Visual observation for short-circuiting/ daylighting of injection fluids to ground surface will be noted. The data obtained will be used to support any adjustments in injection rates or pressures and to confirm that overall injection targets are met. Should the monitoring data indicate that excessive groundwater mounding, short- circuiting and/or daylighting at the ground surface is occurring, the injections will be temporarily stopped, and injection flow rates/pressures will be reduced, and/or the injection layout will be re- configured. 4.4.4 Injection Point Destruction and Site Restoration After injections have been attempted at all three lifts at an injection point, injections will cease and the manifold at the surface of the injection point will be allowed to depressurize. The injection manifold will then be disconnected,the injection rod will be retracted,and the injection rig will be mobilized to the next injection point. Subsequently, the boring will be tremie grouted in accordance with applicable regulations. All injection points are proposed within the paved asphalt parking lot(Figure 4),and concrete with black dye or hot-patch asphalt will be used for surface restoration. Former Source Area Injection Work Plan 10 August 08,2019