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WELL INSTALLATION AND INTERIM REMEDIAL ACTION REPORT <br />www.arcadis.com <br />FINAL_Forward CHCF (CDCR) Well Installation Report_10182024 <br /> <br />20 <br />treated groundwater from the existing Forward Landfill point of compliance groundwater extraction treatment <br />system (GWTS). <br />6.5 System Construction <br />This section outlines pre-field and construction activities planned for GWET system implementation. <br />6.5.1 Underground Utility Locating <br />Utility locating will be performed before commencing construction activities. Arcadis personnel will mark all <br />proposed conveyance line and utility trenching and concrete pad locations in advance of utility locating. <br />Underground Service Alert of Northern California will be contacted to mark out utilities at the Site at least two <br />business days before the start of intrusive work. A geophysical survey using a combination of ground-penetrating <br />radar and electromagnetic utility locating equipment, metal detectors, utility locators, and conductivity meters will <br />be performed to screen designated areas for utilities, buried metallic objects, and anomalies. <br />6.5.2 Permits <br />Necessary permits will be obtained from state and local agencies having jurisdiction over various aspects of the <br />work. These will include, but may not be limited to, a waste discharge requirement permit from the RWQCB and <br />building and electrical permits from the City of Stockton Building Department. <br />6.5.3 Equipment and Enclosure <br />The process flow diagram and piping and instrumentation diagram for the GWET system are shown on Figures 9 <br />and 10, respectively. The expected sustained total extraction flow rate of the four extraction wells is 140 gpm. As <br />a result, the GWET system will be designed for at least that total expected flow. <br />The influent and effluent equalization tanks were sized to 5,000-gallons allow for continuous flow at 140 gpm <br />while allowing for short-term variations in the individual well flow rates. The transfer pumps will be sized to allow <br />for continuous flow with a modulation in the flow rates to maintain an optimal level of water accumulation in the <br />transfer tanks. Variable frequency drives coupled to level control will vary the operation of the pumps to m aintain <br />a relatively constant water level in the influent and effluent equalization tanks. <br />The treatment system will sit atop a concrete pad with berms for secondary containment. The volume of <br />secondary containment will contain at least 110% of largest system tank volume in addition to rain from a 24-hour, <br />25-year storm event. The concrete pad/secondary containment will be equipped with a sump and a sump pump to <br />transfer accumulated water to the influent equalization tank for treatment. <br />6.5.4 Conveyance Piping and Connections <br />Groundwater from the extraction wells to the GWET system compound will be conveyed via belowground piping. <br />The belowground groundwater extraction conveyance lines will be constructed of high-density polyethylene piping <br />and transitioned to schedule 80 PVC when it daylights at the system compound. The proposed conveyance line <br />routing is shown on Figure 8. The treated discharge line, conveying water to the existing infiltration basin, will be <br />placed above ground using high-density polyethylene piping.