ARCHIVED REPORTS_2020 ADDITIONAL SITE ASSESS RPT

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21 October 2020 Project No. 14-3002 Page 11 of 15 Analytical results of samples collected between 10 and 15 feet bsg are summarized in Tables 1 and 6; PCB results and the approximate extent of PCB-impacted soil above the DTSC-SL are depicted in Figure 8. No additional PCBs were reported above laboratory detection limits in the soil and waste samples analyzed. Analytical results of PCBs in all samples is summarized in Table 1. Analytical results of PCBs at each sampling depth (surface, 3, 5, 7, and 10 feet) are summarized in Tables 2 through 6. PCB results and impacted soil above the DTSC-SL are illustrated in Figures 4 through 8. The laboratory reports (MAI Work Orders 2006B65, 2006C29, 2006D41, and 2006D64; and Caltest Lab Order: V060910), quality assurance and quality control (QA/QC) reports, and chain of custody forms are included in Appendix D. Laboratory electronic deliverable format (EDF) files were QA/QC checked and uploaded to the State Water Board GeoTracker site. 5.4. ANALYTICAL RESULTS OF SOIL AND WASTE SAMPLES - TPH A total of forty-one (41) soil samples and six (6) waste samples (waste and mixed waste/soil) collected from borings B44 through B51, B56, B58, B63 through B68, and B79 were analyzed for TPH as listed in Section 3.3. The following is a summary of laboratory results:  TPH-g were detected in a total of five (5) samples. TPH-g was detected in B46-5, B47-10, B47-15, B48-5 and B65-15 at concentrations of 1.2 mg/kg, 2.0 mg/kg, 3.2 mg/kg, 1.6 mg/kg and 33 mg/kg, respectively. TPH-g concentrations were significantly below the ESL of 2,000 mg/kg.  TPH-d were detected in a total of nineteen (19) samples at concentrations ranging from 1.3 mg/kg in B45-5 and B46-14 to 2,400 mg/kg in B47-15. Elevated concentrations of TPH-d were detected at 5 feet bsg in B46, B66, B67 and B68 (58 mg/kg to 1,000 mg/kg); at 10 and 15 feet bsg in B47 (210 and 2,400 mg/kg); and at 15 feet bsg in B65 (1,100 mg/kg). TPH-d was detected above the DTSC-SL of 500 mg/kg in five (5) samples; and above the ESL of 1,200 mg/kg in one (1) sample.  TPH-mo were detected in a total of eighteen (18) samples at concentrations ranging from 5.5 mg/kg in B79-5 to 7,500 mg/kg in B47-15. Elevated concentrations of TPH-mo were detected at 5 feet bsg in B46, B66, B67 and B68 (200 mg/kg to 2,800 mg/kg); at 10 and 15 feet bsg in B47 (800 and 7,500 mg/kg); and at 15 feet bsg in B65 (6,100 mg/kg). TPH-mo was not detected above the DTSC-SL of 18,000 mg/kg. No additional TPH were reported above laboratory detection limits in the soil and waste