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IM hydrocarbon encountered in the samples obtained from boring B-5. Elevated concen' rations of TPH, toluene, xylenes, and ethylbenzene were detected in seven of the ten samples obtained at depths from six to 50 feet bgs in boring B-6. No organic lead was detected in any of the Samples tested, and the TPH concentration in the sample collected at 50 feet bgs was 7. 3 ppm. The concentrations of total and soluble lead were well below the standards contained in Title 22. For specifics regarding the activities completed at the Site by EAI, see EA11s report titled "Phase II Site Assessment Report 5400 Pacific Avenue, Stockton (Site Code 2163) ,11 dated May 20, 1991. Ward suspected that a broken sewer line may be the source of contamination in boring B-6. On June 9, 1991, Pacific Pipeline Survey (PPS) was retained by Ward to investigate the existence of a possible break in the sanitary sewer manhole, associated piping, and a clarifier which are located in close proximity to the former location of the underground storage tanks (USTs) . According to this investigation, about one foot of the sewer line was broken. 1.2 PURPOSE OF THIS INVESTIGATION Ward requested that Stone Brothers excavate the soil cover at the location of the suspected broken sewer line identified by PFS on September 12, ,991, in order to repair the damage. EAI was retained by Ward to collect soil samples from beneath the suspected broken sewer line, and from beneath the product Lines associated with the USTs formerly located on the Site. This report presents the findings obtained from completing the above described investigations, and the additional work proposed to attempt to define the extent of contamination encountered by the sewer line and product lines associated W4.th the USTs formerly located on the Site. 2.0 FIELD INVESTIGATION 2.1 INVESTIGATION OF SEWER LINE On September 12, 1991, representatives of Stone Brothers used shovels to hand excavate around the suspected broken sewer line (see Figure 3) . A trench around the sewer line was excavated to an approximate depth of 2.5 feet bgs. This excavation exposed a red 4-inch clay sewer pipe that extended north from a manhole approximately 3 feet to where it was coupled with a 4-inch cast iron sewer pipe. The cast iron pipe extended northward under the Ward building. From the manhole -north,- the -clay pipe was- otally encased in concrete for a Project No. 1232 -2- F,,%,VIROAF1111.�'AITA L AUDIT,IA7C.,