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<br /> Site Background Information
<br /> AGE-NC Project No. 02-0950
<br /> Page 3 of 4
<br /> water samples collected from all three borings at maximum concentrations of 550µg/1(B3),23,000
<br /> µg/l (131), 6,100 µg/1 (131), and 33,000 µg/l (131), respectively. 1,2-DCA was detected in ground
<br /> water samples collected from all three borings at a maximum concentration of 54µg/1 in sample B3.
<br /> EDB was detected in ground water samples collected from all three borings at a maximum
<br /> concentration of 190 pg/l in sample B2. No additional target analytes were detected at or above
<br /> 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) (134-25) 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-1 through MW-3 at concentrations ranging from 6.3 mg/kg
<br /> (MW2-35)to 15 mg/kg(MW 1-35);total lead was not detected above the laboratory detection level
<br /> or 5.0 mg/kg in the samples analyzed from B4. No additional analytes were detected at or above
<br /> laboratory reporting limits.
<br /> One grab ground water sample (134-1120) 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/1 and 11,000 µg/l, respectively.
<br /> Benzene, toluene, ethylbenzene, and total xylenes were detected at concentrations of 11 µg/1,
<br /> 260 µg/1, 430 µg/l and 2,650 µg/l, respectively. The lead scavenger 1,2-DCA was detected in the
<br /> ground water sample at a concentration of 2.2µg/l.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 /> Advanced GeoEnvironmental,Inc.
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