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SB-1 at a depth of 3 . 5 and 5 . 5 bgs, respectively. Boring SB-2 <br />' was hand augered to an estimated depth of 4 . 75 feet bgs in the <br /> sidewall of the excavation and a soil sample (SS-3) was <br /> collected at the termination depth. The boring was terminated <br /> approximately beneath a second sewer line that extends west of <br />' the manhole. <br /> No TPH were detected in any of the three soil samples <br /> associated with the sewer line. However, minor concentrations <br /> of BTXE, bromoform, carbon disulfide, chloroform, <br /> tetrachloroethene, trichloroethene, 1, 1, 2 , 2-tetrachloroethane, <br /> 1, 1, 1-trichloroethane and 1, 1, 2-trichloroethane were detected in <br /> the soil samples. For specifics regarding these activities, see <br /> EAI ' s report titled " Supplemental Subsurface Investigation, <br /> Montgomery Ward Auto Service Center, 5400 Pacific Avenue, <br /> Stockton, California, " dated October 22 , 1991. <br /> 1. 1. 4 Product Line/FuelIsland Investigation <br /> On September 12 and 13 , 1991, 12 slant borings were hand <br /> augered to depths of approximately four feet bgs. The soil <br /> samples (PL-1 to PL-12) were collected along the product lines <br /> which extend between the former fuel islands and the former UST <br /> locations (see Figure 2) . <br /> No detectable concentrations of TPH were present in any soil <br /> samples, except for soil sample PL-7 . TPH (844 ppm) , toluene <br /> (0.95 ppm) ethylbenzene (0. 55 ppm) and xylenes (9 . 55 ppm) were <br /> detected in soil sample PL-7 @ 4--4 . 51 . Benzene was not detected <br /> in soil sample PL-7 . For specifics see EAI ' s report dated <br /> October 22 , 1992 . <br /> 1. 2 PURPOSE AND SCOPE OF INVESTIGATION <br /> EAI was retained to perform a Phase IV Site Investigation to <br /> I attempt to determine the source of contamination encountered at <br /> the Site. The scope of this investigation consisted of: <br /> 1) drilling and sampling four 30 foot borings; 2) analytical <br /> I testing of soil samples; 3) data evaluation; and 4) preparation <br /> of this report. <br /> 2 . 0 FIELD INVESTIGATION <br /> 2 . 1 DRILLING AND SOIL SAMPLING <br /> On July 1, 1992 , four borings (B-7 through B-10) were <br /> drilled and sampled in the vicinity of the sewer line and <br /> product lines associated with the former USTs (see Figure 2) . <br /> The borings were drilled by West Hazmat Drilling Corporation <br /> Of Rancho Cordova, California (State License C57# 554979) , under <br /> Pro]ect No. 1232 -3- <br /> ENVIRONMENTAL AUDIT,INC® <br />