ARCHIVED REPORTS XR0009171 - Laserfiche WebLink

Home Browse Search

' 02 February 2000 • AGE-NC Project No 97-0301 ' Page 5 of 7 ' was generally encountered between 10 feet bsg and 25 feet bsg A blue/green to dark gray, moist, very stiff to hard, fine sandy, clayey silt was generally encountered at depths between 25 and 40 feet bsg A dark brown, saturated, medium dense to dense, silty fine sand was generally encountered between 40 feet bsg and 45 feet bsg A dark gray,very stiff to hard, fine sandy silt was encountered between 45 feet bsg and 50 feet bsg A dark brown, saturated, dense, silty fine sand was generally encountered between 50 feet bsg and 55 feet bsg At 60 feet bsg, a saturated,dark gray silty clay was ' encountered Saturated soil was encountered at 40 feet bsg in borings MW-1, MW-2, MW-3 and MW-4, ground water levels were measured at 35 feet bsg utilizing a Solmst water level meter Boring logs are included in Appendix A General lithology beneath the site in cross-sectional view is depicted in Figures 3 and 4 3 2 FIELD EVIDENCE OF HYDROCARBON-IMPACTED SOIL AND GROUND WATER iPetroleum hydrocarbon odor or petroleum hydrocarbon vapor(using a PID)were observed in soil sample duplicates collected from soil boring MW-1 at depths between 10 feet bsg and 55 feet bsg Slight to moderate petroleum hydrocarbon odor was detected in quarterly ground water samples collected from ground water monitoring wells MW-1, MW-2 and MW-4 I 3 3 GROUND WATER ELEVATION AND GRADIENT i On 20 December 1999,the depths to first encountered ground water in wells MW-1 through MW-4 ' ranged between 29 20 and 29 76 feet below the tops of well casings Ground water elevations were calculated to he between 25 94 feet and 26 12 feet below mean sea level, ground water elevations, as measured on 20 December 1999, are depicted in Figure 9 The general ground water gradient at ' the site was calculated to be approximately 0 003 ft/ft or approximately 16 feet per mule, the general ground water flow direction was inferred to be towards the east i34 ANALYTICAL RESULTS OF SOIL SAMPLES A total of fifteen soil samples were submitted to a DHS-certified laboratory for analysis of TPH-g, TPH-d,TPH-k,BTEX,MTBE and fuel oxygenates TPH-g,TPH-d and TPH-k were detected in soil samples from MW-1 at 20 and 35 feet bsg at concentrations ranging as high as 7,000 milligrams per ' kilogram (mg/kg) BTEX compounds were detected from MW-1 at 20 and 35 feet bsg and at • concentrations ranging as high as 54 mg/kg No fuel oxygenates were detected by laboratory 1 Advanced GeoEnvironmental,Inc � i