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Site Background Information
<br />' AGE-NC Project No 02-0950
<br /> Page 3 of 4
<br />' 23,000 µg11 (B1), 6,100 µg11 (BI), and 33,000 ggll (B1), respectively 1,2-DCA was detected in
<br /> ground water samples collected from all three borings at a maximum concentration of 54 µg11 in
<br /> sample B3 EDB was detected in ground water samples collected from all three borings at a
<br /> tmaximum concentration of 190 µg11 in sample B2 No additional target analytes were detected at
<br /> or above laboratory detection limits in the ground water samples analyzed
<br /> Four soil borings, MW_1, MW-2,MW-3, and B4 were advanced on 09, 10, and 16 October 2003
<br /> for the collection of soil samples and Installation of three ground water monitoring wells (MW-1,
<br /> MW-2, and MW-3) B4 was properly abandoned with a grout slurry to EHD specifications Pilot
<br />' borings MW-1,MW-2, and MW-3 were completed as ground water monitoring wells of the same
<br /> designations using 2-inch diameter PVC casing with 0 020-inch slotted screen installed from
<br /> approximately 14 feet to 34 feet bsg The filter pack (No 2/12 Lonestar sand) was Installed from
<br /> approximately 12 feet to 34 feet bsg, and a nominal 2-foot bentonite chip plug was installed above
<br /> the filter pack and hydrated The wells were grouted to near the surface with Portland cement, and
<br /> water-tight, traffic-rated well boxes were installed over the wells
<br /> A total of 13 soil samples were analyzed for TPH-g, TPH-d, BTEX, five fuel additives, lead
<br /> scavengers,and total lead TPH-g was detected in soil samples collected from borings B4 and MW-2
<br /> '. at concentrations of 12 milligrams per kilogram (mg/kg) (B4-25) and 1 8 mg/kg (MW2-35)
<br /> Benzene, toluene, ethylbenzene, and total xylenes were detected in soil samples collected from
<br /> borings B4 and MW-2 at maximum concentrations of 0 044 mg/kg (MW2-35), 0 27 mg/kg
<br /> ' (MW2-35), 0 15 mg/kg(134-25),and 0 35 mg/kg(MW2-35),respectively Total lead was detected
<br /> in all samples analyzed from borings MW-/through MW-3 at concentrations ranging from 6 3
<br /> mg/kg(MW2-35)to 15 mg/kg(MW 1-35),total lead was not detected above the laboratory detection
<br /> ' level or 5 0 mg/kg in the samples analyzed from B4 No additional analytes were detected at or
<br /> above laboratory reporting limits
<br /> One grab ground water sample (B4-H20) was taken from boring B4 at an approximate depth of
<br /> 53 feet bsg and was analyzed for TPH-g, TPH-d, BTEX, five fuel additives, and lead scavengers
<br /> TPH-g and TPH-d were detected at concentrations of 14,000 µg/l and 11,000 µg/l, respectively
<br /> ' Benzene, toluene, ethylbenzene, and total xylenes were detected at concentrations of 11 µg11,
<br /> 260 µg11, 430 µg/l and 2,650 µg11, respectively The lead scavenger 1,2-DCA was detected in the
<br /> ground water sample at a concentration of 2 2 µg11 No additional analytes were detected at or above
<br /> ' laboratory reporting limits
<br /> ' SENSITIVE RECEPTOR SURVEY
<br /> On 10 April 2004, an AGE representative reviewed well driller's reports from the California
<br /> ' Department of Water Resources - Central District for water wells located In the surrounding area
<br /> Driller's reports for 14 water wells located within a 2000-ft radius of the site were identified
<br /> tAdvanced GeoEnvrronmental,Inc
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