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1 v 3 A S S O C I A T E S I N C gasoline, (TPHg) by EPA method 8015 modified, benzene, toluene, ethylbenzene, and xylenes (BTEX), and oxygenate fuel additives by EPA method 8260 1 Soil samples collected from bonngs SB2 and SB3 exhibited visual evidence of petroleum contamination and PID readings were elevated in the deepest samples Based on this information, 1 it was decided in the field not to collect grab groundwater samples from the soil borings 3.0 SUBSURFACE CONDITIONS ' The soil column in boringSB 1 consisted ea ravel from the surface to 8 feet bgs The soil from P g g depths between 8 feet bgs and 20 feet bgs in boring SB 1 consisted of silt with sand and poorly graded sand with lean clay present from 12 to 13 feet bgs The soil column from depths between 20 and 38 5 feet bgs consisted of well graded to poorly graded sand The soil consisted of lean ' clay from depths between 38 5 and 45 feet bgs The soil column in boring SB I consisted of clayey sand and silty sand from depths between 45 and 50 feet bgs, the maximum depth explored The soil in borings S132 and SB3 consisted of silt with sand from the surface to depths of approximately 16 5 feet bgs The soil consisted of poorly graded sand with varying amounts of silt from depths between approximately 16 5 and 31 5 feet bgs Soil boring logs with a detailed description of soil types are contained in Appendix A ' 4.0 ANALYTICAL RESULTS The soil sample collected from boring SB 1 at a depth of 15 feet bgs contained low concentrations of TPHg, ethyl benzene, and xylenes Concentrations of TPHg, benzene, ethylbenzene, and xylenes increased by approximately one order of magnitude in the sample collected at a depth of 30 feet bgs The soil sample collected from boring SBI at a depth of 49 5 bgs contained only 1 trace amounts of xylenes and contained no detectable concentrations of TPHg or benzene Soil samples collected from borings SB2 and SB3 at 30 5 feet bgs contained low concentrations of TPHg and BTEX None of the soil samples from borings SBI, SB2, and SB3 contained 1 detectable concentrations of oxygenate fuel additives Analytical results of soil samples are summarized in Table 1 Laboratory data sheets and chain-of-custody documentation are presented in Appendix B 5.0 CONCLUSIONS Based on the analytical results and field observations, the soil in the vicinity of the former USTs and fuel dispenser is impacted with low to moderate concentrations of TPHg and BTEX The impacted soil appears to attenuate rapidly with depth as indicated by the decreasing TPHg and BTEX concentrations in boring SBI when comparing the soil sample collected at 30 feet to the soil sample collected at 49 5 feet The lateral extent of impacted soil has not been defined to the north or northeast of the former USTs and fuel dispenser, but the low concentrations of w 162605Veportslsum doc 3