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Cr¢ologicalTeclucicslnc. Page 7 ' Well Installation and Quarterly Groundwater Monitoring Report • Project No. 1030.2 ' .lune I8,2002 3.1 Analytical Results Soil In summary: • BTEX and TPH-G were found in the 13.5 to 14 foot sample from MW-101. 0 The 20 to 20.5 foot sample from MW-101 was non-detect for all analyzed constituents. Minor levels of xylene were detected in the 24.5 to 25 foot and 32.5 to 33 foot samples. ' • MTBE was non-detect in all samples collected from MW-101. Groundwater ' In summary: • Elevated levels of BTEX and TPH-G were detected in MW-1. • Minimal levels of BTEX constituents were detected in MW-4. MW-2, MW-3, MW-101 and the domestic well were non-detect for all analyzed constituents. These wells have been non-detect throughout the history of this project. ' • Fuel oxygenates including MTBE were non-detect in all monitoring wells. a Historically there has been no fuel oxygenates detected at this site. 3.2 Geology and Field Observations The following section discusses the subjective field observations and geology documented during this investigation based on the interpretations of the field geologist. • The geology between 0 and 14 feet bgs is characterized by clay and silt, primarily gray in color with varied degrees of plasticity. + A sand layer was between 14 and 19 feet bgs. This unit is similar to a sand unit found at approximately the same depth in other boreholes on site. ' • A clay layer was encountered between 19 and 22 feet bgs. This unit is similar in each borehole at the site. ' • From 22 to 34 feet bgs are alternating sand layers. The layers range from Clayey Sand to Gravely Sand. • Highly plastic clay was encountered at approximately 34 feet bgs. ' 3.3 Hydrology of Site On June 11, 2002, the depth to groundwater was measured in all of the wells prior to ' purging. Depths to groundwater ranged from a high of 8.78 feet below the top of casing to a low of 9.25 feet below the top of casing. Groundwater was measured in all the wells on June 11, 2002. The average groundwater elevation for the June event was 67.56 feet above ' mean sea level (MSL). This is the highest groundwater elevation recorded at this site.