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1 <br />' 03 October 2001 <br /> • AGE-NC Project No. 95-0100 <br /> Page 4 of 6 <br /> 2.8. GROUND WATER SAMPLING <br /> Following well purging,ground water levels in monitoring wells MW-1,MW-2,MW-3,MW-5 and <br /> MW-6 were allowed to achieve a minimum of 80 percent recharge of the initial casing water level <br /> prior to sample collection. The water level in well MW-4 did not achieve a minimum of 80 percent <br /> recharge of the initial casing water level.Well MW-4 was sampled one-hour after the well had been <br /> purged. Ground water samples were collected from the purged wells utilizing new, disposable <br />' polyethylene bailers and three 40-m1 volatile organic analysis (VOA) vials containing 0.5 ml 18% <br /> hydrochloric acid as a sample preservative. Care was taken to ensure that visible air bubbles were <br /> not present in the vials after filling and capping.The samples collected were properly labeled,placed <br /> in a chilled container and transported under chain-of-custody to MAI a DHS-certified laboratory.The <br /> ground water samples were analyzed for: <br /> ' • TPH-g in accordance with EPA Method 8015 Modified; <br /> • BTEX with MTBE in accordance with EPA Method 60218020; and <br /> • Oxygenated compounds - di-isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), <br /> MTBE, tertiary-amyl methyl ether(TAME) and tertiary butanol (TBA) in accordance with <br /> ' • EPA Method 8260 Modified; <br /> 3.0. FINDINGS <br /> ' Ground water elevation, flow direction, and gradient were determined from field data collected on <br /> 03 July 2001, the contaminant impact to soil and ground water was assessed from the laboratory <br /> analytical data obtained from samples collected during the we(1 installation and sampling events. <br /> 3.1. STRATIGRAPHY <br /> Generally,brown,damp,poorly graded sand was encountered at 40 feet bsg and brown,moist,silty <br /> clay to silt was encountered at 45 feet bsg. Brown,saturated,silt to silty sand was encountered at 50 <br /> feet, 55 feet and 60 feet bsg in boring MW-5 and at 50 feet and 55.feet bsg in boring MW-6.Brown, <br /> saturated, silty clay to clay was encountered at 60 feet bsg in borings MW-4 and MW-6. Brown, <br /> saturated poorly graded sand to silty sand was encountered at 65 feet, 80 feet, 85 feet, 90 feet and <br /> T­--100 feet bsg.'Brown to°tan; damp to saturated silt and clay were encountered-at 70-feet;-75 feet and- <br /> 95 <br /> nd 95 feet bsg. <br /> ' Organic vapor was not detected inthe soil samples collected from borings MW-4,MW-5 andMW-6. <br /> • PID data is included on the boring logs (Appendix A). <br /> Advanced GeoEnvironmental,Inc. <br />