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Weldon Church Site Background Information Page 4 of 12 sample B16-5.5 at 0.006 mg/kg. The fuel additive MTBE was detected in the four soil samples analyzed from borings 1317 and B18, at a maximum concentration of 0.29 mg/kg (B17-5), and was detected in soil samples collected from total depth in both borings, at a concentration of 0.012 mg/kg. No other target analytes were detected in the samples analyzed. Seventeen ground water samples were analyzed; TPH-g and BTEX compounds were detected only in the grab ground water samples collected at water-table depth (approximately 10 feet bsg) and at total depth of borings B17 and B18. The highest concentrations of contaminants were detected in the water table samples at 160,000 pg/1 TPH-g in sample B17-1, and 5,600 pg/I benzene, 14,000 pg/I toluene, 3,200 pg/I ethylbenzene, and 12,000 pg/I xylenes in sample 1318-1. At total depth, maximum TPH-g concentration was 3,900 pg/I (1318-2); however, the BTEX concentrations were considerably lower; benzene was not detected, maximum toluene concentration was 3.8 pg/I (B18-2), maximum ethylbenzene concentration was 2.2 pg/1 (1317-2), and maximum xylene concentration was 16.8 pg/I (1318-2). No other target analytes were detected in the samples analyzed. On 16 and 17 August 2010, four soil borings were advanced at the site using a Marl M-2.5 DP drill rig equipped with 1.25-inch diameter probe rods. Pilot borings MW-8 and B-27 were advanced to a total depth of 25 feet below surface grade (bsg), boring ATB-1 was advanced to 12 feet bsg, and boring ATB-2 was advanced to 21 feet bsg. After reaching total depth, the pilot boring for MW-8 was advanced using 8-inch diameter hollow-stem augers for the installation of a 2-inch diameter monitoring well. Drilling services were provided by Gregg Drilling of Martinez, California. Soil samples were collected continuously from borings MW-8 and B-27 at four-foot intervals beginning at five feet bsg and extending to 25 feet bsg. Pilot soil boring MW-8 was completed as a ground water monitoring well using two-inch diameter, schedule 40 polyvinylchloride (PVC) casing with 0.020-inch slotted screen installed from approximately 5 feet to 25 feet bsg and with blank casing extended to the surface. A total of five soil samples from soil boring MW-8. TPH-g were detected in all five soil samples at concentrations ranging from 2.0 milligrams per kilogram (mg/kg) in the 16-foot soil sample to 1,600 mg/kg in the 10-foot soil sample. Three or more BTEX constituents were detected in all five soil samples at maximum concentrations of 0.36 mg/kg benzene, 15 mg/kg toluene, 13 mg/kg ethylbenzene and 55 mg/kg total xylenes(MW-8-10). Benzene was not detected above laboratory reporting limits in the 7-foot soil sample collected from MW-8. MTBE was not detected above laboratory reporting limits the soil samples analyzed. A total of 28 soil borings have been advanced on and off the site, eight of which have been completed as ground water monitoring wells, providing data concerning hydrocarbon impact on soil and ground water, soil composition, and ground water flow direction. Laboratory analysis of soil samples collected from monitoring wells and soil probe borings Advanced GeoEncironnental,hie.