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19 June 2000 AGE-NC Project No 96-0232 Page 8 of 35 A six-inch diameter ground water extraction well (EW-1)was installed on-site to a depth of 33%2 feet bsg for interim remediation measures (Figure 2), a well construction diagram of EW-1 is depicted in Figure 20, a boring logof EW-1 is in Appendix B,neither soil or ground water samples were collected dunng installation of EW-1 Five soil borings (P13, P14, P15, P16 and P17) were advanced on-site utilizing cone penetrometer testing(CPT) technology to characterize the geological and hydro-geological framework and to assess preferential migration pathways CPT soil boring locations are depicted in Figure 3, CPT boring logs are in Appendix B Based on soil composition data obtained from the CPT soil borings P 13,P14, P 15,PI 6 and PI 7, cross sections C-C',D-D' and E-E'were constructed depicting the general subsurface soil composition on-site and off- site (Figures 21, 22 and 23) Ground water monitoring and sampling was performed at wells MW-1, MW-2, MW-4, MW-5, MW-6 and MW-7 Ground water depths were recorded at approximately 7 feet bsg (Table 3), general ground water flow direction was generally between north-northeast and north-northwest at a general gradient of 0 003 (Figure 24) Laboratory analysis of ground water samples collected from MW-1,MW-2,MW-4,MW-6A,MW-6B and MW-7 detected MTBE at concentrations as high as 400 gg/l, BTEX compounds were detected in samples collected MW-1,MW-2,MW-6A and MW-6B at concentrations as high as 2 3 µg/1, TAME and ETBE were detected in samples collected from MW-1 and MW-2 at concentrations as high as 1 2 µg/1 Ethanol was detected in samples collected from MW-1, MW-2, MW-6A and MW-6B at concentrations as high as 50 µg/1, methanol was detected in the sample collected from MW-6A at a concentration of 420 gg/1 Analytical results of ground water samples are summarized in Table 5 A grab ground water sample collected from RDW-1 detected MTBE at a concentration of 12 µg/1 (Table 7) A report of findings (Quarterly Report - First Quarter 2000, dated 01 May 2000) documenting investigation activities performed in March 2000 was prepared by AGE and submitted to the PHS-EHD and the RWQCB-CVR • April 2000 - Grab ground water samples were collected adjacent to CPT soil borings P13, P14, P15, P16 and P17 Dissolved MTBE was detected in the 37 to 40-foot, 53 to 56-foot, 70 to 73-foot and 87 to 90-foot samples collected from P16 at concentrations of 270 µg/1, 280 µg/1, 55 µg/1 and 6 µg/1, respectively Dissolved MTBE was detected in the 37 to 40-foot, 55 to 58-foot and 80 to 83-foot samples collected from P17 at concentrations of 110µg/1, 150 µg/1 and 4 9 µg/l, respectively Dissolved TBA was detected In the 37 to 40-foot sample collected from P16 and the 111 to 114-foot sample from P-17 at concentrations of 6 µg/1 and 7 1 µg/l, respectively Dissolved methanol was detected in the 64 to 67-foot and the 73 to 76-foot samples collected from P 13 at concentrations of 85 µg/1 Advanced GeoEmironmental,Inc