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NWW�- 3.0 Analytical Results The analytical results for the confirmation samples and the composite sample collected from the soil stockpile are summarized in Table 1. Sample locations are shown on Figure 2. The ,.., complete analytical results are provided in Appendix C. BTEX, MTBE and PCBs were not detected in any of the samples. TPHG, TPHD and oil and grease were not detected at the more northerly of the two dispensers (gasoline)but were detected beneath the southerly dispenser(diesel). At the southerly dispenser, TPHG was detected in two samples at concentrations very near the 1-milligram per kilogram (mg/kg) detection limit. TPHD concentrations beneath the southerly dispenser ranged from 2.7 mg/kg to 96 mg/kg. Oil and grease were also detected in the two samples with the highest concentrations of TPHD. Total lead concentrations ranged from 3.7 mg/kg to 11 mg/kg. Selected laboratory quality control (QC) data were evaluated to assess the acceptability of the analytical data. The QC evaluation, including the significance and implications of any noncompliant QC data, is summarized below. • All analyses were performed within USEPA-recommended holding times. V • Laboratory method blanks were analyzed at the required frequencies for all analyses. No compounds were detected in the method blanks at or above the reporting limits. V • Surrogate spike recovery results for all organic analyses were within laboratory acceptance limits, with one exception. The surrogate recovery for sample SP-5 was not reported because the sample required a dilution, which diluted out the surrogate. Because surrogate recoveries were acceptable in all other samples, including all QC samples, data usability is likely not affected. V • Matrix spike and matrix spike duplicate (MS/MSD) analyses were performed for TPHD, MTBE, and total lead. MS and MSD results, and the relative percent differences (RPDs) between the duplicate results were within acceptance limits, with one exception. The MS and MSD recoveries, and the BPDs between the duplicate results, for TPHD were outside acceptance limits due to possible matrix interference. USEPA guidelines state that no action is taken based on MS/MSD data alone. Because precision and accuracy were verified by acceptable laboratory control sample results, data usability is likely not affected. • Laboratory control sample (LCS) and laboratory control sample duplicate (LCSD) results were reported for all analyses. The LCS and LCSD recoveries, and the RPDs between the duplicate results were within the laboratory acceptance limits. SuCDP-\\SACRFPACOMMOt&.CDP12OONRMJM21924.1 m.&a 3-1 4111101 V