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' 21 August 2000 . AGE-NC Project No 95-0104 Page 4of6 3 1 RELATIVE GROUND WATER ELEVATION AND GRADIENT ' During the June 2000 sampling event, depths to ground water in wells MW-1, MW-5, MW-6 and ' VW-1 were measured between 57 84 and 58 35 feet below the tops of well casings, between the November 1999 and the June 2000 ground water monitoring events, ground water elevation at the site increased an average 2 94 feet The ground water elevation data for wells MW-1,MW-5,MW-6 ' and VW-I during the June 2000 ground water monitoring event is depicted in Figure 3 and shown on Table 1 ' Ground water flow direction was generally toward the southeast at a gradient of 0 07 ft/ft, or approximately 370 feet per mile (Figure 3) Ground water was approximately 5 16 feet above the screen interval at MW-5 and 8 80 feet above the screen interval at MW-6 Therefore these wells are ' "drowned", and may yield samples more representative of deeper ground water conditions rather than that of shallowest ground water,which is commonly the more intensely impacted by petroleum hydrocarbons Monitoring well MW-1 and vapor extraction well VW-1 are screened across the top ' of the saturated zone '• 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES A total of four ground water samples were submitted to a DHS-certified laboratory for analysis in ' June 2000 TPH-g was detected in a water sample collected from well MW-5 at a concentration of 88 micrograms per liter (µg/1) ' BTEX compounds were detected in the ground water sample collected from VW-1 at a maximum concentration of 0 85 µg/l (benzene) ' MTBE was detected by EPA Method 8260 in the ground water sample collected from MW-5 at a concentration of 1 2 µg/1 No other fuel oxygenated compound was detected at or above laboratory ' reporting limits in the ground water samples collected Analytical results of the ground water samples are summarized in Table 2 The laboratory reports(McCambell Analytical Inc Lab I D No 42075 through 42078) and chain-of-custody forms are presented in Appendix C 1 33 STRATIGRAPHY ' Pea gravel was encountered from surface grade to approximately 15 feet bsg Generally, orangish brown,dry,silt with fine sand was encountered at 20 feet to 35 feet bsg Brown,damp,poorly graded sand with silt was encountered at 40 feet bsg Gray to brown,dry to damp,silty clay was encountered • at 45 and 50 feet bsg A soil sample was not recovered at 55 feet bsg 1 Advanced GeoEnviron mental,Inc 1