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I <br /> ISTRATIGRAPHY <br /> I Generally, gray, orange-brown to dark-brown, dry silt with sand and gravel (fill material) was <br /> encountered from surface grade to approximately 6 feet below surface grade (bsg) Light yellow- <br /> orange-brown to dark brown, damp to moist clays, clayey silts, and clayey sands were encountered <br /> from approximately 6 feet to 21 feet bsg Brown, blue-gray to dark-gray, saturated, fine to coarse <br /> sand and silty sand were encountered from approximately 21 feet to 29 feet bsg,but to almost 35 feet <br /> bsg in the area of MW-2 Gray to blue-gray, moist to saturated clay with medium to high toughness <br /> and plasticity was encountered from approximately 29 feet to 36 feet bsg Blue-gray to green-gray, <br /> saturated silt was encountered from approximately 36 feet to 49 feet bsg in soil boring B4 Green- <br /> gray, saturated fine sand was encountered from appioximately 49 feet bsg to total depth in soil <br /> boring B4 <br /> IPREVIOUS SITE ASSESSMENTS <br /> I On 15 and 16 October 2002, three soil borings (B1 though B3)were advanced to a depth of 35 feet <br /> bsg utilizing a van-mounted Geoprobe 5400 direct-push probing unit equipped with 1 25-inch <br /> probing rods, for the collection and analysis of soil and `grab' groundwater samples After probing <br /> Ito a depth of 25 feet bsg, ground water was found to be at approximately 22 feet bsg <br /> Soil boring B 1 was advanced in the northwest corner of the former UST excavation, soil boring B2 <br /> Iwas advanced approximately 5 feet east of the former UST excavation, and soil boring B3 was <br /> ie advanced approximately 10 feet southwest of the former UST excavation <br /> A total of six soil samples were analyzed for the petroleum hydrocarbon products TPH-g was <br /> detected in soil samples collected from all three borings at a maximum concentration of <br /> 22,000 milligrams per kilogram (mg/kg) in sample B2-15 TPH-d was detected in soil samples <br /> collected from borings BI and B2 at a maximum concentration of 7,500 mg/kg in sample B2-15 <br /> BTEX compounds were detected in soil samples collected from all three borings at maximum <br /> concentrations of 1 1 mg/kg, 460 mg/kg, 320 mg/kg, and 1,830 mg/kg, respectively, in sample <br /> B2-15 Lead was detected by EPA Method 6010B in one soil sample collected in boring B2 at a <br /> concentration of 59 mg/kg in sample B2-15 No additional analytes were detected at or above <br /> laboratory detection limits in the soil samples analyzed <br /> Agrab ground water sample was collected from each of the three bann s on 15 and 16 October 2002 <br /> and analyzed for the petroleum hydrocarbon products TPH-g was detected in groundwater samples <br /> collected from each boring at a maximum concentration of 170,000 micrograms per liter (gg/1) in <br /> boring B2 TPH-d was detected in ground water samples collected from borings B1 and B2 at a <br /> maximum concentration of 23,000 gg/1 in boring B2 BTEX compounds were detected in ground <br /> water samples collected from all three borings at maximum concentrations of 550 µg/1(B3), 23,000 <br /> µg/1 (Bl), 6,100 lig/1 (131), and 33,000 gg/1 (B1), respectively 1,2-DCA was detected in ground <br /> i water samples collected from all three borings at a maximum concentration of 54 4g/1 in sample B3 <br /> EDB was detected in ground water samples collected from all three bonngs at a maximum <br /> concentration of 190 lig/1 in sample B2 No additional target analytes were detected at or above <br /> iAdvanced GeoEn"ronmental,Inc <br /> i <br />