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3.5 SOIL SAMPLING LDuring the drilling of UVB-MW 1, soil samples were collected at 5-foot intervals using a California modified split spoon sampler The contents of the split spoon sampler were examined for soil characteristics and screened with a photo-ionization detector (PID) to determine the relative hydrocarbon content Soil samples were not collected during the destruction of RW3 or during the drilling of UVB-MW2, due to the close proximity to UVB-MW 1 None of the soil ' samples collected from UVB-MW 1 were submitted to the laboratory for analysis, because the site has been characterized in previous investigations A soil boring log describing the soil characteristics of UVB-MW 1 and the PID readings for UVB-MW 1 are provided in Appendix A ' All soil cuttings were placed on and covered with plastic sheeting and temporarily stored on the site Four soil samples were collected from the soil stockpile and composited into one sample in ' the laboratory The samples were analyzed for TPH-g, BTEX, and halogenated VOCs to classify the soil for disposal A copy of the laboratory analytical report for the soil stockpile sample is provided in Appendix C ' 3.6 WELL INSTALLATION The borehole resulting from the removal and overdrilling of RW3 was completed as a groundwater/soil remediation well on 25 November 1996 and the boreholes for UVB-MW 1 and UVB-MW2 were completed as groundwater monitoring wells on 11 February 1997 The wells were installed in accordance with the Tri-Regional Board Staff Recommendations for Preliminary Evaluation and Investigation of Underground Tank Saes (RWQCB 1990), EA's ' protocols (Appendix B), and the well permit conditions issued by the San Joaquin County Department of Public Health Services 3.6.1 UVB Well The UVB well was constructed with 16-inch-diameter galvanized steel blank casing (0 25-inch wall thickness) placed from 2 0 feet above ground surface to 24 8 feet bgs Two separate screen intervals were placed in the well, the upper interval was constructed of 0 04-inch slot double- cased galvanized steel screen placed from 24 8 to 32 feet bgs and the lower interval was ' constructed of 0 025-inch slot Irigator° screen placed from 35 5 to 39 5 feet bgs A filter pack consisting of medium aquarium sand was placed around the upper screen from 22 5 to 32 feet bgs and around the lower screen from 34 5 to 43 feet bgs An additional half foot of#30 fine ' sand was placed from 22 to 22 5 feet bgs in the upper screen interval Both intervals were sealed with a 2-foot layer of bentonite placed above the filter pack Construction details are summarized in Table 2 and shown on the well construction diagram provided in Appendix A ' 3 6.2 UVB Monitoring Wells Wells UVB-MW 1 and UVB-MW2 were constructed with 2-inch-diameter Schedule 40 PVC well casing and screened with 0 020-inch machine-slotted Schedule 40 PVC The screen for UVB-MW 1 was placed from 35 to 40 feet bgs, and the screen for UVB-MW2 was placed from 24 to 32 feet bgs A filter pack of#3 Lonestar sand was placed from 33 to 40 feet bgs in UVB- WP61 73942 ROI397 1 8