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08 November 2004 AGE-NC Project No. 04-1215 Page 2 of 4 In November 1990, one 12,000 gallon diesel UST was removed from the central portion of the subject property. Analytical results of soil samples collected from UST excavation were non-detect or below Maximum Contaminant Levels (MCL) for kerosene, motor oil, diesel and BTEX constituents(benzene,toluene, ethylbenzene and total xylenes).Field notes from an inspector from the San Joaquin County Environmental Health Department(EHD)did not indicate any discoloration or odor. AGE viewed a 1970/72 Sanborn Fire Insurance Map which showed two structures and a canopy, plus a"Gas and Oil'notation, on the subject property location; the structures and canopy matched features depicted on 1993 and 1970 aerial photographs. DRILLING On 12 October 2004, five soil borings(B-1 through B-5)were advanced at the site utilizing a van- mounted Geoprobe 5400 direct-push probing unit equipped with 1.25-inch probing rods. Borings B-1 through B-4 were advanced in the area of the former gasoline station: • Boring B-1 was advanced to a depth of approximately 55 feet below surface grade (bsg) within the suspected tank pit area; • Boring B-2 was advanced to a depth of approximately 25 feet bsg within the suspected piping area; • Boring B-3 and B-4 were advanced to a depth of approximately 15 feet bsg in the area of the suspected dispenser location. Boring B-5 was advanced in the former tank pit of the 12,000 gallon diesel UST removed in 1990. All sampling equipment was washed in an Alconox solution and rinsed twice with water prior to each sampling run. Soil boring locations are depicted on Figure 2. SOIL SAMPLE COLLECTION AND LOGGING Soil samples were collected from the borings at discrete five-foot intervals using a 1.5-inch Geoprobe soil sampling assembly loaded with four six-inch brass sleeves. For each soil sample collected,both ends of the second or other selected sleeve were covered with Teflon sheets,capped and sealed with tape. Each sample was properly labeled and stored on ice for transport to a State of California Department of Health Services (DHS)-certified laboratory for analysis. Advanced GeoEnvironmental,Inc.