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w , <br /> Each ground monitoring well was completed with 20 feet of well screen section. The wells were <br /> constructed using two 2-inch diameter, schedule 40 PVC casing with the following designs and <br /> material: Monitoring well MW- 1 was completed with 0.02-inch slotted screen, the screen interval <br /> was installed from depths of 15 to 35 feet bsg. A filter pack was installed using #3 Lonestar sand <br /> from 13 to 35 feet bsg. Bentonite chips were used to make a one-foot transition seal above the sand <br /> pack. Monitoring wells MW-2 through MW-4 were completed with 0.02-inch slotted screen, the <br /> screen interval was installed from depths of 10 to 30 feet bsg. A filter pack was installed using #3 <br /> Lonestar sand from 9 to 30 feet bsg. Bentonite chips were used to make a one-foot transition seal <br /> above the sand pack. The remaining annular space was backfilled to within six inches of surface <br /> grade with portland cement. A traffic-rated well box (8-inch diameter) was installed over each well, <br /> in accordance with County regulations. <br /> • TPH-g was detected in one ofthe twelve soil samples analyzed (MW 1 - 15) at a concentration <br /> of 990 milligrams per kilogram (mg/kg). BTEX compounds were also detected in the same <br /> soil sample at concentrations of 3 .9 mg/kg, 33 mg/kg, 17 mg/kg and 110 mg/kg <br /> respectively. BTEX compounds were also detected in two other soil samples collected from <br /> boring MW- 1 . Toluene, ethyl benzene and total xylene were detected in sample MW 1 -30 at <br /> concentrations of 0.012 mg/kg 0.005 mg/kg and 0.028 mg/kg respectively. BTEX <br /> compounds were detected in sample MWl -35 at concentrations of 0.008 mg/kg, 0 . 024 <br /> mg/kg, 0 .007 mg/kg and 0. 037 mg/kg, respectively. Soil samples collected from the other <br /> soil borings (MW-2 through MW4) did not contain detectable concentrations ofpctroleum <br /> hydrocarbons. The oxygenated compound MTBE was not detected in the soil samples <br /> analyzed. <br /> On 06 November 2000, two ground water wells were installed off-site. Soil boring/monitoring wells <br /> MW-5 and MW-6 were advanced at the site as part of assessment activities related to the former <br /> USTs at the site. Soil borings MW-5 and MW-6 were advanced vertically to depths of 25 bsg. Soil <br /> borings MW-5 and MW-6 were completed as ground water monitoring wells utilizing 2-inch <br /> diameter, schedule 40, blank polyvinylchloride (PVC) well casing from 10 feet to 25 feet bsg and <br /> perforated, 2-inch diameter PVC well casing (0. 020-inch slot) from 10 feet bsg to surface. A filter <br /> pack was installed using #3 Lonestar sand from 8 feet to 25 feet bsg. Bentonite chips were used to <br /> make a one-foot transition seal above the sand pack. The remaining annular space was backfilled to <br /> within six inches of surface grade with portland cement. A traffic-rated well box (8-inch diameter) <br /> was installed over each well, in accordance with County regulations. <br /> • TPH-g, BTEX compounds and MTBE were not detected in the soil samples analyzed. <br /> On 14 November 2000, three soil probe borings (P9 through P 11) were advanced at the site, under <br /> observation by the EHD . Probe borings were advanced in the area of the former USTs and in the <br /> areas north and east of the former UST dispenser. Boring P9 was advanced to a depth of 35 feet <br /> below surface grade (bsg), boring P10 was advanced to a depth of 40 feet bsg and boring Pl l was <br /> advanced for collection of a grab ground water sample to 20 feet bsg. <br /> Advanced GeoEnvironmental, Inc. <br />