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' Each ground monitoring well was completed with 20 feet of well screen section The wells were constructed using two 2-inch diameter, schedule 40 PVC casing with the following designs and ' material Monitoring well MW-1 was completed with 0 02-inch slotted screen, the screen interval was installed from depths of 15 to 35 feet bsg A filter pack was installed using #3 Lonestar sand from 13 to 35 feet bsg Bentonite chips were used to make a one-foot transition seal above the sand ' pack Monitoring wells MW-2 through MW-4 were completed with 0 02-inch slotted screen, the screen interval was installed from depths of 10 to 30 feet bsg A filter pack was installed using#3 Lonestar sand from 9 to 30 feet bsg Bentonite chips were used to make a one-foot transition seal above the sand pack The remaining annular space was backfilled to within six inches of surface grade with portland cement A traffic-rated well box(8-inch diameter)was installed over each well, in accordance with County regulations • TPH-g was detected in one of the twelve soil samples analyzed(MW1-15)at a concentration of 990 milligrams per kilogram (mg/kg) BTEX compounds were also detected in the same ' soil sample at concentrations of 3 9 mg/kg, 33 mg/kg, 17 mg/kg and 110 mg/kg, respectively BTEX compounds were also detected in two other soil samples collected from boring MW-1 Toluene,ethyl benzene and total xylene were detected in sample MWI-30 at concentrations of 0 012 mg/kg, 0 005 mg/kg and 0 028 mg/kg, respectively BTEX compounds were detected in sample MWI-35 at concentrations of 0 008 mg/kg, 0 024 ' mg/kg, 0 007 mg/kg and 0 037 mg/kg, respectively Soil samples collected from the other soil borings(MW-2 through MW-4) did not contain detectable concentrations of petroleum hydrocarbons The oxygenated compound MTBE was not detected in the soil samples � . analyzed ' On 06 November 2000,two groundwater wells were installed off-site Soil boring/monitonng wells MW-5 and MW-6 were advanced at the site as part of assessment activities related to the former USTs at the site Soil borings MW-5 and MW-6 were advanced vertically to depths of 25 bsg Soil ' borings MW-5 and MW-6 were completed as ground water monitoring wells utilizing 2-inch diameter, schedule 40, blank polyvinylchlonde (PVC) well casing from 10 feet to 25 feet bsg and perforated, 2-inch diameter PVC well casing (0 020-inch slot) from 10 feet bsg to surface A filter pack was installed using#3 Lonestar sand from 8 feet to 25 feet bsg Bentonite chips were used to make a one-foot transition seal above the sand pack The remaining annular space was backfilled to within six inches of surface grade with portland cement A traffic-rated well box (8-inch diameter) ' was installed over each well, in accordance with County regulations • TPH-g, BTEX compounds and MTBE were not detected in the soil samples analyzed On 14 November 2000, three soil probe borings (P9 through P11)were advanced at the site,under ' observation by the EHD Probe borings were advanced in the area of the former USTs and in the s areas north and east of the former UST dispenser Boring P9 was advanced to a depth of 35 feet below surface grade (bsg), boring P10 was advanced to a depth of 40 feet bsg and boring P1 I was ' advanced for collection of a grab ground water sample to 20 feet bsg Advanced GeoEnvironmental,Inc 1