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06 February 2003 AGE-NC Project No. 98-0504 Page 3 of 9 and l.0 mg/kg xylenes(north wall,east end);benzene was only detected in the sample from the west wall, north end at a concentration of 0.02 mg/kg. MTBE was detected in all but two samples from the south wall of the excavation at a maximum concentration of 1.3 mg/kg (west wall, north end). TBA was detected in all but two samples from the south wall and the eastern floor sample at a maximum concentration of 89 mg/kg (west wall, north end). DIPS, ETBE and TAME were detected in the sample from the west wall, north end at concentrations of 0.03 mg/kg, 0.18 mg/kg and 0.18 mg/kg, respectively. Analytical results of soil samples are summarized in Tables 1 and 2. 2.4. PREVIOUS SITE ASSESSMENTS It is AGE understanding that an environmental site assessment was performed on the property in the early 1996. Field observations indicated that hydrocarbons may have impacted the soil. Subsequent laboratory analysis detected BTEX compounds in one soil sample (5.3 micrograms/kilogram xylenes) collected from forty feet bsg and two grab ground water samples at maximum concentrations of 3.4 micrograms/]iter (µg/l) benzene, 1.3 µg/1 toluene, 6.8 µg/l ethylbcnzene and 11 µ;/l xylenes. In addition, one of the two ground water samples contained 'l-PH-g and MTBE at concentrations of 0.28 mg/1 and 3.7 µg11, respectively. On 31 July 2002,three soil probe boring(B3, B4 and B5)were advanced east and west of the former UST excavation, and north of the former dispenser area. Discrete soil samples were collected at 5-foot intervals, beginning at 10 feet bsg, to the total depth of the wells at between 35 and 40 feet bsg. In addition, a grab ground water sample was collected from each well at total depth. TPH-g and BTEX compounds were not detected in soil samples collected. MTBE was detected by EPA method 8260 in three soil samples at concentrations of 0.016 mg/kg (133-30), 0.008 mg/kg (134-20) and 0.006 mg/kg (134-30). Analytical results of soil samples are summarized in Table 3. TPH-g was detected in the grab ground water samples from boring B3, B4 and B5 at concentrations of 240 µg11, 300 µg11 and 180 µg/l, respectively. BTEX compounds were not detected, but MTBE and 1,2-DCA were detected by EPA method 8260 in each of the ground water samples at maximum concentrations of 200 µgll (134) and 13 µg/1 (35). The distribution of dissolved MTBE is depicted in Figure 3, and analytical results from ground water samples are summarized in Table 3. Advanced GeUEitvirOnlnental,Inc.