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f1 jV Mr Harlin Knoll November 14, 2000 Page 3 of 4 No discoloration or petroleum odors were noted in the cuttings or samples collected from the boring FID readings of the vapor headspace for all bagged soil samples were non-detect A soil boring log is included in Attachment A Soil samples collected at depths of 30 and 47 feet bgs, as well as the groundwater sample collected from the boring, were analyzed for TPHg using EPA method 8015 modified, BTEX using EPA method 8020, and oxygenated gasoline additives including MTBE by EPA method 8260 No TPHg, BTEX, or oxygenated gasoline additives were detected in the analyzed soil samples TPHg was detected at a concentration of 120 parts per billion (ppb) in the grab groundwater sample collected from the boring No BTEX or oxygenated gasoline additives were detected in the groundwater sample Analytical results of soil and groundwater samples are summarized in Table 1 Laboratory reports and chain of custody documentation are included in Attachment B GROUNDWATER MONITORING AND SAMPLING An experienced Ground Zero technician measured the depth to groundwater in each site well on August 10, 2000 The depth to groundwater beneath the site ranged from 33 93 feet below ground surface (bgs) in well MW3 to 35 83 feet bgs in well MW6 Groundwater elevations fell an average of 4 37 feet between May and August 2000 The water table beneath the site lies . above the screened intervals for all wells except MW1, MW2 and MW3 Monitoring well construction details are summarized in Table 2 Groundwater monitoring data are summarized in Table 3 The groundwater flow in the vrciruty of the former USTs was generally southeast at gradient of 0 006 ft/t, or approximately 32 ft/mile A potentiometric surface map for August 10, 2000 is presented on Figure 3 Monitoring wells MW1, MW2, MW3, MW4, MW5, and MW8 were sampled on August 10, 2000 A rmmmum of three well casing volumes of water were purged from each well prior to sampling The temperature, specific conductance, and pH of the water were measured and recorded while each well was purged of the required volume Purged groundwater was placed in labeled drums approved for storage of liquid waste by the Department of Transportation (DOT) pending disposal Copies of field purge logs and water level measurements are included in Attachment C Groundwater samples were submitted to Argon Laboratories (FLAP #2359) for analysis of TPHg and BTEX utilizing EPA methods 8015 modified and 8020, respectively Groundwater Analytical Results Elevated levels of dissolved gasoline constituents were detected in the groundwater sample collected from well MW5, low levels were detected in well MW1, and only very low levels of Knowles hmnhepoftV3cp QW0 doc