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' 05 October 2007 AGE-NC ProjectNo.07-1537 tPage 5 of 8 ' brown to dark yellow-brown clay or silty clay. A dark yellow-orange brown to dark-yellow brown sandy silt was encountered in pilot borings MW4 and MW5 at approximately 24 and 50 feet bsg,and 10 and 30 feet bsg, respectively, and a dark yellow-brown sand was encountered in pilot boring ' MW6 at approximately 25 feet bsg. Boring logs are included in Appendix D. The CPT-generated soil types from near-surface to approximately 100 feet bsg at the CPT-l location ' consisted dominantly of fine-grained soil (silt, clayey silt, silty clay and clay). Sand and silty sand was identified at approximate depths from 21 to 24 feet bsg, and 99 to 105 feet bsg. In addition, significant intervals of what the CPT identified as dense fine grained soil occurred from 7 to 11 feet bsg, 14 to 17 feet bsg, 59 to 67 feet bsg, 73 to 76 feet bsg, and 95 to 98 feet bsg. CPT computer- generated boring logs are included in Appendix C. ' Based on the CPT computer-generated boring log, and boring logs from this and previous investigations, geologic cross sections A-A' through C-C' were constructed depicting the general soil profile beneath the site (Figures 3-5). ' 3.2. ANALYTICAL RESULTS OF SOIL SAMPLES A total of fifteen soil samples collected from pilot borings MW4, MW5 and MW6 and four soil ' samples collected from one boring atthe CPT-1 location(CPT1-15,CPTl-67,CPT1-80,and CPT1- 90) were analyzed for the constituents listed in Section 2.1.2: ' • TPH-g was detected in the soil sample collected from CPT1-15 at a concentration of 710 milligrams per kilogram (mg/kg); • BTEX compounds were detected in the soil samples collected from CPT 1-15,CPT 1-67,and ' CPTl-90. Toluene was detected at concentrations of 1.7 mg/kg (CPT1-15), 0.14 mg/kg (CPT 1-67), and 0.021 mg/kg (CPT 1-90). Ethylbenzene was detected at a concentration of ' 9.0 mg/kg(CPT 1-15).Xylenes were detected at concentrations of 91 mg/kg(CPT 1-15),0.016 mg/kg (CPT1-67), and 0.024 mg/kg (CPT1-90). • MTBE was detected in the soil samples collected from CPT 1-67 and CPT 1-90 at concentrations of 0.030 mg/kg, and 0.010 mg/kg, respectively. ' No constituents of concern were detected in soil sample CPT1-80 or in the soil samples collected from borings MW4, MW5 and MW6. ' Analytical results of the soil samples are summarized in Table 1. The laboratory reports (CTEL Project Nos.CT214-0705205 and CT214-0706140),quality assurance and quality control(QA/QC) reports, and chain of custody forms are included in Appendix F. Laboratory electronic deliverable ' Advanced GeoEvironmental,Inc.