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L A kT H CO N ; _A Monitoring Well Zone Hydrologic Layer Lithology Screened in Interval III Uppermost Water Bearing Unit Fine Sand to Silty MW-7 (Aquifer) Sand IV Aquitard Clay and Silt MW-2A, MW-3A, MW-9A V Lower Aquifer (Semi-Confined) Sand MW-10A, MW-1 1, MW-12, MW-13, MWRR-1, MWRR-2, & MWRR-3 MW-7 is located in Zone III completed to a total depth of approximately 40 feet. In comparison, total well depths in Zone V range from approximately 57 feet bgs to 74 feet bgs. Zone V is present on all sides, an beneath the landfill and provides the most representative and comparable, groundwater for evaluating compliance. In addition, the screen interval in MW-7 extends from approximately 29 feet to 40 feet, therefore, it is adjacent to the waste, which extends to a depth of approximately 35 feet. This configuration may allow water to migrate laterally from the screened interval into the landfill. Furthermore, the water encountered at approximately 33 feet during the installation likely represents localized perched water(Zone III)that is not in direct contact with the first continuous water bearing unit (Zone V). The groundwater at the Site historically flows in a general northeasterly direction. Therefore, monitoring well MW-11 is a representative upgradient well based on its depth and location within the lower aquifer and is an appropriate replacement for MW-7. A.4 Identification of Monitoring Well to be Abandoned As identified above, EarthCon is proposing the abandonment of monitoring well MW-7. A.5 Site Map A scaled Site map showing the existing wells, proposed well to be abandoned (MW-7), surface water bodies (Duck Creek), and direction of groundwater flow is provided in Figure 2. MW Abandonment Workplan MW-7 Stockton,Ca Cove Contractors, Inc. 3 Project No.04.20090407.00