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16 August 2001 AGE-NC Project No. 01-0852 Page 4 of 7 NP 1 sampled the new pond area and OP 1 sampled an old pond area.IVP i was collected by pushing the sampling sleeve into the moist soil; OP1 was collected from the backhoe. 4.0. ANALYTICAL RESULTS MTBE and benzene were not detected in any of the samples analyzed for hydrocarbons. TPH-g was detected at a concentration of 0.12 milligrams per kilogram (mg/kg) in sample T2-5, and at a concentration of 0.59 mg/kg in sample T34.Sample T34 also contained 0.022 mg/kg toluene,0.036 mg/kg ethylbenzene, and 0.18 mg/kg total xylenes. Ethanol was detected in sample T2-5 at a concentration of 0.80 mg/kg. Hydrocarbons were not detected in any other samples analyzed,for hydrocarbons. Hexavalent chromium was initially detected in samples T4-1 and T8-2 at concentrations of 9.8 mg/kg and 2.4 mg/kg,respectively.The deeper samples in each location,T4-5 and T8-5 had less than detectable concentrations of hexavalent chromium(< 0.2 mg/kg). Soil samples from T1.6,T17,T1 8 and T19 were collected around T4-1 to attempt to define the lateral extent ofsoil impacted byhexavalent chromium;all the samples contained detectable concentrations of hexavalent chromium ranging from 1.8 mg/kg to 8.2 mg/kg,as shown on Figure 4 and in Table 1. Soil samples from T20,T21,T22 and T23 were collected around T8-2 to attempt to define the lateral extent of soil impacted by hexavalent chromium;all the samples contained detectable concentrations of hexavalent chromium ranging from 1.0 mg/kg to 4 mg/kg, as also shown_ on Figure 4 and in Table 1. No other samples were analyzed for hexavalent chromium. 5.0. DISCUSSION OF RESULTS The detected hydrocarbons and ethanol in sample T2-5 suggests a release from the large AST on the north, the smaller ASTs on the south, or a spill in the immediate area. The lack of detectable hydrocarbon or ethanol concentrations in samples T10-5 and T11-5 minimizes the possibility that the release was from the large AST. The smaller ASTs south of the sampling point were on an area currently covered by a concrete slab sloped to drain fluids to the localities of T1 and T2. If the analytes detected in T2 were the result of a release from the.southern ASTs or a spill above T2,the release appears to have been limited and the inferred volume of impacted soil appears to be minimal. The detected hydrocarbons in sample T3-4 suggests a release from in the area of the former distillation unit. Lack of detectable concentrations of hydrocarbons in samples from T13, T14 and T15 are suggestive of a limited release in the area of T3-4; the low concentrations detected in T34 are not high enough to be likely to trigger regulatory agency interest. Advanced GeoEnvironment;l,Inc.