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1 concentrations ranging from 6 to 36 ppm were present in all of the samples tested. For specifics regarding the activities completed at the Site by ADS, see their report titled "Underground Tank Removal Area ' Evaluation, Montgomery Ward Site, Stockton, California, " dated June 20, 1988 . ' 1. 1. 2 Additional Site Assessment In March 1991, Environmental Audit, Inc. (EAI) drilled and t sampled two borings (borings B-5 and B-6) at the Site to determine whether operation of the former gasoline tank systems impacted the environment (see Figure 2) . Borings B-5 and B-6 were terminated at a depth of about 31. 5 and 51. 5 feet bgs, ' respectively. Ground water was not encountered during drilling. No TPH, benzene, xylenes or ethylbenzene were detected in any of the samples collected from boring B-5. Toluene (ranging from ' 0. 01 to 0. 14 ppm) was the only aromatic hydrocarbon encountered in the samples obtained from boring B-5. Elevated concentrations 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 . A solvent odor was noted during drilling of this boring. 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 by EAI at the Site, see EAI ' s report titled "Phase II Site Assessment Report 5400 Pacific Avenue, Stockton (Site Code 2163) , " dated May -'IV, 1991. IT 1. 1. 3 Sewer Line Investigation IWard 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 gasoline storage tanks (USTs) . According to this investigation, about one foot of the sewer line was broken. on September 12 , 1991, representatives of Stone Brothers excavated a trench around the suspected broken sewer line to an approximate depth of 2 . 5 feet bgs (see Figure 2) . Two slant borings were drilled around the sewer line using a hand auger. Commencing near the base of the clay pipe (2 . 5 feet bgs) , boring SB-1 was hand augered to a calculated vertical depth of 5. 75 feet bgs. Two soil samples (SS-1 and SS--2) were collected from Proaect No. 1232 -2- ENVIRONMENTAL AUDIT,INC®