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I ti ' 26 September 2003 AGE-NC Project No 95-0128 ' Page 5 of 8 ' Water sample containers were labeledwiththe sample designation,date,time,and sampler's initials Subsequently,the samples were logged on a chain-of-custody form,placed in a chilled container and transported to MAI The samples were analysis for • TPH-g and TPH-d by EPA Method 8015 Modified, and • BTEX and MTBE by EPA Methods or 8020 or 8260 I In addition, to satisfy SPWD Industrial Wastewater Discharge Permit No 01, the pH of effluent ' ground water samples collected were analyzed in accordance with EPA Method 150 1 ' 3.0. FINDINGS Ground water elevations were determined by subtracting the measured depths-to-water from the ' surveyed casing elevations Ground water flow directions were determined by contouring the water elevations on a scaled site plan Contaminate impact to ground water samples was assessed by laboratory analysis The mass of hydrocarbons removed by ground-water extraction was calculated ' from the volume of water treated and the concentrations of contaminants from laboratory analysis Soil descriptions were incorporated into the site hydrogeologic model ' 3 1 STRATIGRAPHY AND GROUND WATER OCCURRENCE IFine grained soil,primarily silt,was encountered at from the surface to 20 feet bsg in boring MW 18 Poorly graded sand was encountered at 20 feet bsg in the same boring Silt was encountered at 30 ' feet to 40 feet bsg Clay with low percentage of silt was present in the soil sample collected from 40-foot and 60-foot samples from the boring Sandy silt was encountered at 50 and 65 feet bsg in the same boring Petroleum hydrocarbon odor was not noted in the samples collected Saturated soil was ' observed at 35 feet bsg and the ground water table was observed to occur at 30 feet bsg 3 2 GROUND WATER ELEVATION AND GRADIENT The depth to ground water on 24 February 2003 ranged from 31 64 feet (MW-15) to 34 48 feet (MW-13)below the well casings The ground water elevation calculated from the same data,ranged from 20 05 feet(MW-10) to 21 22 feet (MW-14) below mean sea level(MSL), the average ground water elevation was approximately 1 14 feet lower than the average ground water elevation during the November 2002 monitoring event The ground water table occurred within the screened interval of the shallow-screened monitoring wells(Table 1),wells MW-1 to MW-3,MW-11 B and MW-12B IAdvanced GeoEnvironmental Inc