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• Contamination was detected in the deepest recovered sample from MW-6 at a depth of 65 feet bsg One soil sample collected from the pilot boring for MW-8 contained 1,2-DCA at a concentration of 15 mg/kg Soil samples from the pilot boring for MW-7 did not contain detectable concentrations of analytes of concern TPH-g, BTEX and 1,2-DCA were detected in the initial ground water samples collected from MW-6, MW-7 and MW-8 Details of the procedures and results of the monitoring well installation were presented in Monitoring Well Installation Report-Fourth Quarter 2000, dated 16 January 2001, prepared by AGE VERTICAL SITE ASSESSMENT On 10 October 2002, a soil boring (CPT-01) was advanced vertically on-site to a total depth of approximately 147 feet below surface grade (bsg), utilizing CPT technology to characterize the geological and hydrogeological framework and to identify potential contaminant-migration pathways beneath the site Based on the CPT lithologic sounding data, depth-discrete "grab" ground water samples and a soil sample were collected in a "twin" soil boring placed immediately adjacent to CPT-01,the water samples collected were assigned the boring designation of the initial CPT boring (CPT-1) However,the twin boring could only achieve a maximum sampling depth of approximately 117 feet bsg before encountering refusal LABORATORY RESULTS OF SOIL/CPT"GRAB" GROUND WATER SAMPLES • Only one soil sample (CPT1-1-85) was collected and submitted for analysis during the Fourth Quarter 2002 TPH-g, toluene, ethylbenzene, and total xylenes were detected in the sample at concentrations of 1 6 mg/kg, 16 micrograms/kilogram(gg/kg),5 1 µg/kg and 24µg/kg,respectively, benzene was not detected in the soil sample A total of two "grab" ground water samples were collected from CPT-01,between 96 and 100 feet bsg and between 113 and 117 feet bsg TPH-g was detected in both samples at concentrations of 13,000 µg/1 and 140,000 µg/l, respectively BTEX compounds were detected in both samples at concentrations as high as 4,600 µg/1 benzene, 16,000 µg/1 toluene, 2,100 µg/1 ethylbenzene and 11,000µg/1 total xylenes(CPT-01-113-117) In addition, 1,2-DCA was detected in both samples at concentrations of 8 8 µg/1 and 250 gg/l,respectively EDB was detected in sample CPT-01-113-117 at a concentration of 90 µg/1 ADDITIONAL MONITORING WELL INSTALLATION/ABANDONMENT Between 14 October and 23 October 2002, soil borings were advanced at the site to install monitoring wells MW-8B, MW-9A/B, MW-IOA/B, MW-11A/B and MW-12A/B and one ground water monitoring/extraction well EX-1 Pilot borings MW-8B,MW-9A/B,MW-10AB,MW-IIA/B and MW-12AB were completed as ground water monitoring wells using two-inch diameter PVC casing with 0 020-inch slotted screen The screen was installed from approximately 15 to 35 feet bsg • in MW-9A through MW-12A, and from 60 to 65 feet bsg in wells MWBB through MW-1213, with Advanced GeoEnvironmental,Inc