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' CL Properties, VI E37801.02B 1 December 30, 1999 Page 3 • two sampling points adjacent (across West Sonora Street) and downgradient to the current dry cleaner facility. The proposed soil sampling points were not be advanced in an easement or right-of-way controlled by a municipal government. Nor were the sampling points be advanced to less than 15 above the 1 estimated groundwater depth. Therefore, municipal permits were not be required for this assessment. An application for a soil boring permit was submitted to and approved by the SJCEHD. 1 The soil vapor assessment included the collection of five soil vapor samples from the vicinity of the former dry cleaning facility located at 513 South Center Street and two soil vapor samples adjacent (across West Sonora Street) from the active dry cleaning facility. The soil vapor sampling points were placed in the vicinity of most likely areas of contamination, including the exterior sewer and 1 subsurface utility trenches. A truck mounted Geoprobe®drilling rig was used to drive the sampling rods with a 1-inch expendable sampling tip to the desired depth (five feet BSG). The rods were partially retracted in preparation for sampling. ' The sampling points were connected to a vacuum pump with clean polyethylene tubing and an in- line regulator. A maximum gas flow rate of 200 cubic-centimeters per minute was applied to the system to purge all of the residual gas. A minimum of three tubing volumes was purged prior to sample collection to assure that samples are representative of soil vapors. Samples were then collected in Tedlaro bags and placed into ice chests containing blue ice for transport to the off-site laboratory. All reusable sampling equipment was decontaminated before,and between uses,in order 1 to reduce the possibility of cross-contamination. The vapor samples were analyzed off-site by SunStar Laboratories, Inc. of Tustin, California, a state certified and accredited laboratory. 1 Soil vapor samples were submitted for laboratory analysis. Sample handling procedures are summarized in our SOPS. One sample from each boring was submitted for analysis. The analytical results for soil vapor samples is summarized in Subsection 5.1. This data was evaluated to determine if further assessment of the extent of HVOC migration in soil and or groundwater is necessary,The results of this evaluation is presented in Subsection 6.0. After completion of the soil sampling,the sampling points was backfilled with a neat cement slurry. Backfill was placed in one continuous operation from the bottom to the top of the borehole. Due to the nature of the sampling method, no cuttings from the installation of the soil vapor sampling points were generated. 4.2 Laboratory Testing Program: Soil vapor samples collected from the area of the former dry cleaner facility and adjacent(across West Sonora Street) current dry cleaner facility were tested in the laboratory for halogenated volatile organic constituents(HVOCs)including,tetrachloroethylene (PCE), trichloroethylene (TCE), vinyl chloride, Stoddard solvent, and other HVOCs. Preparation and analytical methods for the laboratory analyses are summarized in Table 1. i 1