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placed immediately adjacent to the former UST pit(Figure 6). The SVE wells were completed as shallow zone (18 to 38 feet bgs) and deep zone 40 to 60 feet bgs)within each well. Soil samples were collected from the two SVE wells during installation. The soil samples were submitted to Kiff Analytical, Davis, California for analysis of petroleum hydrocarbon compounds. Analytical laboratory results are tabulated in Table 3. The 2010 soil sample analytical laboratory results indicated that elevated concentrations of TPH-g (1,000 mg/kg)were present in the soil beneath the former UST pit. The concentrations of TPH-g in soil appear to be greatest from depths of about 20 to 40 feet bgs (Figures 9, 10 and 11). A report of well installation was submitted to PHSEHD by Muir (2011 a). The SVE pilot test was conducted during a period of 20 days during June to August, 2010 (Muir, 2011 a). Four zones (two shallow and two deep)were utilized to determine the concentration of petroleum hydrocarbons in the soil column and physical properties to evaluate the SVE remediation technology. An air-sparge pilot test was also conducted during February, 2011 using PT-SVE2 deep zone as an injection well (Muir, 2011b). The results from the pilot study was used to determine if air- sparging was a viable remedial technology. A Problem Assessment Report(PAR)was submitted to PHSEHD that reported the nature, extent and estimated volume of soil and groundwater contamination at the former Parmer Texaco site. The PAR included results of a sensitive receptor survey conducted during 2003 and 2010. The PAR also updated the previous Site Conceptual Model (SCM). The PAR indicated the remaining presence of approximately 15,000 pounds of volatile organic compounds (VOC) in the soil column on the site and approximately 3 pounds of VOCs are contained in the dissolved phase of the first water bearing zone. The petroleum hydrocarbon contaminated groundwater extends off the site. The summary of the SVE pilot test was submitted to PHSEHD in 2011 (Muir, 2011b). The pilot test results indicated that both SVE and air sparging technologies could be used successfully at the site to remove volatile organic compounds from the subsurface. During the pilot test approximately 2,700 pounds of TPH-g contaminant mass was removed from the subsurface (Muir, 201 lb). Quarterly groundwater monitoring has been conducted as directed by PHSEHD during 2003 to 2016. To date, a total of twenty six (26) quarterly monitoring events have been conducted at the site. Table 7 tabulates groundwater monitoring data for the individual monitoring events. Table 8 tabulates groundwater sample analytical laboratory results. The groundwater monitoring has shown the groundwater plume extends offsite to the south and southwest(Figure 12). Parmar\Site Assessment Workplan\02152018.wpd 7