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r , Ms Lori Duncan Page 5 of 7 . 3.5 Domestic Well Sampling On June 7, 2001, a Ground Zero technician collected a water sample from the domestic supply well located at 8723 N Davis Road, which is immediately north of the subject property The well is located generally downgradient of the former UST at North Stockton Auto Service Water samples were collected from a port at the well after having run the pump Depth to water in the well was measured at 29 90 feet below grade Depth to bottom was not determined The water sample was immediately placed in an iced cooler and delivered under chain of custody to Argon for analysis The sample was analyzed for VOCs and oxygenated fuel additives by EPA Method 8260 Field notes are included in Attachment B 4.0 RESULTS OF INVESTIGATION 4.1 Subsurface Conditions The general stratigraphy encountered in boring MW 1 consisted of a 22 to 24 5 thick sand unit (clayey sand, well-graded sand and poor-graded sand), which overlies a fine-grained bed consisting of silt and silty clay approximately 10 feet in thickness Underlying the bed of fine grained soil another coarse grained bed consisting of silty sand and well graded sand persists to a depth of approximately 44 feet bgs where a sand/clay contact was found The clay extended to . boring termination (45 feet) Groundwater was initially encountered at a depth of approximately 33 feet and subsequently rose to approximately 29 feet bgs PID readings from samples collected in boring MW 1 ranged from zero to 4 8 parts per million (ppm) Background levels ranged from 0 7 ppm to 1 0 ppm No petroleum hydrocarbon or solvent odors, and no abnormal discolorations were noted in the soil samples collected from the boring 4.2 Soil Analytical Results No detectable concentrations of TPHg, VOCs or gasoline oxygenates were detected in the soil sample Soil analytical results are summarized in Table 2 Laboratory reports and chain of custody documentation are included in Attachment C 4.3 Groundwater Analytical Results - Monitoring Well MW 1 The only detectable concentration of any analyte in the water sample from monitoring well MW 1 was 2 2 parts per billion (ppb) of chloroform Analytical results of groundwater samples are summarized in Table 5 Laboratory reports and chain of custody documentation are included in Attachment C d-kL-t\grounzcins-iutolreporls'nvzilreport d0L