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4.8 2006 Soil Gas Survey LNC retained Geomatrix to conduct a soil gas survey of the LNC site at 110 East Turner Road during 2006 as part of its effort to investigate VOCs within the soil at the LNC site. This work was conducted under the oversight of the RWQCB. Between October 16 and 20, 2006, Geomatrix advanced 14 soil borings (SV-1 through SV-3 and SV-5 through SV-15) at locations shown on Figure 8. Drilling activities were conducted by Precision Sampling, Inc., of Richmond, California,using a trailer mounted direct push rig. Soil vapor samples were collected at depth intervals of approximately 6, 10, and 15 feet bgs for shallow borings. Samples from deeper borings (SV-1, SV-6, SV-7, and SV-14)were collected at depth intervals of 6, 20, and between 26 and 29 feet. The samples collected from between 26 and 29 feet were planned to be collected from approximately a 40-foot depth. However, refusal of the direct push drive rod was encountered, so in each of the deep borings, a soil gas sample was collected at the greatest depth reached. Soil gas samples were collected using Summa canisters provided by Air Toxics, Inc., of Folsom, California. Soil vapor samples were analyzed for VOCs by U.S. Environmental Protection Agency(USEPA) Test Method TO-15 for the following list of analytes: TCA, DCA, PCE, TCE, cis-1,2-dichloroethylene (cis-1,2 DCE), trans-1,2-dichloroethyleno (trans-1,2 DCE), DCE, 1 ,2-dichloroethane (1 ,2-DCA), and 2-propanol. These VOCs (other than the 2-propanol) were selected as target analytes because these chemicals were detected at multiple locations in previous soil vapor and soil samples (WZI, 1996). At least one target analyte was detected in each of the soil vapor samples collected and analyzed(Geomatrix, 2006). The soil vapor analytical results range in analyte concentrations are summarized below. M ain\D:AEnvironmentaI\LN CV\10152007.wpd 26