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16 October 2014 AGE Project No. 13-2675 Page 2 of 9 A total of four soil samples collected from borings B1 through B3 were analyzed for Total petroleum hydrocarbons as gasoline (TPH-g) and volatile organic compounds (VOCs). The following target analytes were detected: • TPH-g were detected in soil samples collected from boring B3 at 15 feet and 20 feet below surface grade (bsg) at concentrations of 31 milligrams per kilogram (mg/kg) and 33 mg/kg, respectively; • Naphthalene was detected in soil samples collected from boring B3 at 15 feet and 20 feet bsg at concentrations of 1.1 mg/kg and 0.66 mg/kg, respectively; and • Benzene, toluene, ethylbenzene, and total xylenes (BTEX) were not detected above laboratory reporting limits in the soil samples analyzed; however, six additional VOCs were detected in soil samples collected from boring B3 at 15 feet and 20 feet bsg at concentrations ranging between 0.011 mg/kg (1,2,4- trimethylbenzene) and 0.52 mg/kg (n-butylbenzene). Analytical results of the soil samples are summarized in Table 1. Grab groundwater samples were collected from borings B1 through B3 and analyzed for TPH-g and VOCs. The following target analytes were detected: • TPH-g were detected in the groundwater sample collected from boring B3 at a concentration of 35,000 micrograms per liter (pg/I); • Toluene, ethylbenzene and xylenes were detected in the groundwater sample collected from B3 at concentrations of 5.4 pg/I , 5.1 pg/I, and 9.3 pg/I, respectively; benzene was not detected above laboratory reporting limits in the groundwater samples analyzed; and • Naphthalene was detected in the groundwater sample collected from B3 at a concentration of 8.3 pg/I; six additional VOCs were detected in the groundwater sample collected from B3 at concentrations ranging between 3.7 pg/I (1,3,5- trimethylbenzene) and 84'mg/kg (1,2,4-trimethylbenzene). Analytical results of grab groundwater samples are summarized in Table 2. Based on the results of the October 2013 limited subsurface investigation, the San Joaquin County Environmental Health Department (SJCEHD) has issued a Notification of Hazardous Waste Discharge; additional sampling and evaluation will have to be completed in order to progress the site towards closure. In order to evaluate the risk associated with the petroleum hydrocarbon impact at the site and move the site towards closure, AGE performed the following scope of work. Advanced GeoGnvironmental,Inc.