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If no anomalies are found in the samples accompanying the trip blank, the trip blank shall not be analyzed. Quality control samples shall be analyzed by US EPA Method TO-15 for the same list of analytes as soil vapor samples. 3.6 SVE and Groundwater Well Installations Shallow Groundwater Monitoring Well After completing the groundwater monitoring well borehole (LNC-MW 1) at total depths between 61 feet and 65 feet bgs, approximately 10 feet into the first water bearing zone, the borehole will be converted into groundwater monitoring wells. The well will be constructed with 2-inch- diameter Schedule 40 PVC casing with 20 feet of screen at the bottom (10 feet below the water table and 10 feet above) followed by blank casing to the surface. Filter pack sand(No. 3 is anticipated)will be emplaced by gravity feed in the annular space from the bottom to a point at least two feet above the screened interval followed by three-feet of hydrated bentonite chips to seal the filter pack. Neat cement-bentonite (5 percent bentonite powder) slurry will be used to fill the annular space to the surface. The wellheads will be equipped with a locking cap and a traffic-rated steel box set in cement slightly above grade to complete the installation. Soil Vapor Extraction Wells Soil vapor extraction wells will consist of shallow wells (<25 feet bgs) and deep wells (up to 60 feet deep)within the vadose zone. Shallow Wells (<25 feet bgs) SVE well casing will consist of 2-inch diameter Schedule 40 PVC with a 0.020-inch slot size screen. The screen interval is planned to span a vertical distance of approximately 20 feet of the upper zone, immediately above the "A" Clay. A coarse-sand filter pack will be placed from the bottom of the screen up to approximately 2 feet above the top of screen interval. A bentonite seal approximately 2-feet thick will be placed on top of the sand pack,and cement-bentonite grout will seal the remaining annular space. At the surface, each well will be completed with a 12-inch diameter steel traffic-rated Environmental/LNC/Workplan/Appendix 2.wpd 6