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I07 November 2003 • AGE-NC Project No 98-0492 ' Page 4 of 9 B 1 at a concentration of 400 gg/I Analytical results of soil and ground water samples collected from ' the March 2000 investigation are presented in Table 4 ' On 05 April 2001, four monitoring wells (MW1 through MW4) were Installed at the site Soil samples were collected and analyzed from each pilot boring Toluene was detected at very low ' concentrations in one sample collected from MW I, in two samples from MW3 and in two samples collected from MW4 at concentrations as high as 0 025 mg/kg MTBE was detected in the soil samples collected from pilot boring MW4 at concentrations as high as 12 mg/kg Concentrations ' of toluene and MTBE were detected only in the soil samples collected from the vadose and saturated zones(15-25 feet bsg) Analytical results of soil samples collected from the April 2001 investigation are presented in Table 5 ' On 08 and 09 January 2002, three cone penetrometer testing borings (CPT1 through CPT3) were advanced at the site MTBE was detected at a concentration of 0 006 mg/kg in the one soil sample ' collected from the CPT investigation(CPT 1-35) Grab groundwater samples were collected at three selected intervals in each CPT boring TPH-d was '• detected just above reporting limits at a concentration of 54 µg/1 in CPT3 at 41 to 45 feet bsg and MTBE was detected at a concentration of 1 6 �ig/1 in CPT3 at 81 to 85 feet bsg Analytical results of soil and grab ground water samples collected from the January 2002 investigation are presented ' in Table 6 On 28 January 2002, three monitoring wells (MW5, MW6 and MW7) were installed at the site ' MTBE was detected at a concentration of 0 0510 mg/kg in one of the seven soil samples collected from monitoring well pilot borings MW5, MW6 and MW7 (MW5-20) Analytical results of soil ' samples collected from the January 2002 well installations are presented in Table 5 In February 2003,three monitoring wells (MW8,MW9 and MW10) were installed at the site Two ' soil samples were collected from each pilot boring MTBE was detected at concentrations as high as 0 064 mg/kg in two of the soil samples collected(MW9-25 and MW 10-28) Analytical results of soil samples collected from the February 2003 well installations are presented in Table 7 Quarterly ground water monitoring has been ongoing at the site since April 2001 TPH-g has only been detected three times since April 2001 TPH-g was detected at a concentration of 85 µg/1 in well ' MW4 in April 2002 and at concentrations of 110 gg/I and 300 µg/1 in well MW5 in January and April 2002, respectively Their have been no other detections of TPH-g in any of the other ground water samples collected at the since sampling began Additionally, TPH-d and BTEX compounds ' have not been detected above laboratory reporting limits in any of the ground water samples . collected from the site since sampling began MTBE has been detected intermittently in samples collected from wells MW1 and MW2 at concentrations as high as 9 3 µg/1 1 Advanced GeoEnvironmental,Izac 1