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Mr Michael J. Infurna Jr. P.G., S.R.E.H.S. August 2, 2006 Page 6 concentrations of 1,600 mg/kg (HA-5-S-1.5') and 720 mg/kg (HA-5-S-3.5'). However, the laboratory report indicated that the TPHg chromatographic pattern for these samples (HA- 5-S-1.5' and HA-5-S-3.5') did not match that of the specified TPHg standard. Ethylbenzene and total xylenes were detected in the same 2 of the 13 soil samples at concentrations of 1.4 and 5.3 mg/kg (HA-5-S-1.5') and 0.62 and 2.1 mg/kg (HA-5-S-3.5'), respectively. Benzene, toluene, and MTBE were not d:it;cted in any of the samples at concentrations equal to or greater than method reporting limits. Onsite Well Analytical Results Analytical results for the sample collected from the onsite well are included in Table 1. TPHg, TPHd, TPHmo, BTEX, and MTBE were not detected at concentrations equal to or greater than method reporting limits in the groundwater sample collected from the onsite well. The sample was also analyzed for a full scan of volatile organic compounds with EPA Method 8260B. With one exception, no VOCs were detected at concentrations equal to or greater than normal method reporting limits. The one analyte detected was 2,2- dichloropropane with a concentration of 1.3 micrograms per liter (ug/L), just greater than the reporting limit of 1.0 ug/L. DISCUSSION The soil profile encountered in the five deeper borings generally consisted of fine grained soils including silt, slit with clay, clayey silt, silt with sand, and silt with gravel and a competent, laterally-continuous hard pan approximately 3.3 feet to 3.5 feet bgs. This suggests that the soil profile naturally displays a relatively low permeability, which may impede or reduce potential leaching into the groundwater beneath the Site of petroleum hydrocarbons found in samples collected from shallow soil. TPHg, TPHmo, BTEX, and MTBE were not found at concentrations equal to or greater than method reporting limits in any of the eight soil samples from borings HA-1 through HA- 4, collected in the area immediately beneath the heavy equipment storage shed (Figure 2). TPHd was found at concentrations ranging from 6.0 to 17 mg/kg in three of the eight samples (HA-1-S-1.5', HA-1-S-3.5', and HA-1-S-3.5'). However, TPHg, TPHd, and TPHmo were reported at significant concentrations in both samples collected from boring HA-5 (HA-5-S-1.5' and HA-5-S-3.5'); HA-5 was advanced in the area southeast of the well and the storage shed (Figures 2 and 3). TPHg, BTEX, and MTBE were not detected in either sample HA-6-S-6" or HA-7-S-2' at concentrations equal to or greater than method reporting limits. Samples HA-6-S-6" and CADocuments and Settings\minfurna\Local Settings\Temporary Internet Files\0LK6F\Final PGE French Camp 2nd Phase II.doc