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' Contamination was detected in the deepest recovered sample from MW-6 at a depth of 65 feet bsg aOne soil sample collected from the pilot boring for MW-8 contained 1,2-DCA at a concentration of ' 15 mglkg 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 ofthe procedures and results ofthe monitoring well ' installation were ptesented 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 hydrogeo logical 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 wei e 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(CPT 1-1-85)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 16 milligrams/kilogram, 16 micrograms/kilogram(gg/kg), 5 1 Mg/kg and 24 ug/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 gg/1 and 140,000 jig/I, 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/l ethylbenzene and 11,000 �tg/1 total xylenes(CPT-01-113-117) In addition, 1,2-DCA was detected in both samples at concentrations of 8 8 4gll and 250 dig/l,respectively and EDB was detected in sample CPT-01-113- ' 117 at a concentration of 90 gg/I 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-1 OA/B,MW-I IA/B and MW-12A/B) and one ground water monitoring/extraction well EX-1 Pilot borings MW-8B,MW-9A/B,MW-10A/B,MW-11A/B and 1\4W-12A/B 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 0 Advanced GeoEnvironmental,Inc 1