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Report of Results Investigation of Agricultural Chemicals in Soil PureGro/Brea Facility 1905 North Broadway Ave.,Stockton,CA Sierra-Pacific Project No.94-055.08 In April 1991, soil samples were collected from three borings located between the drywells by Kleinfelder, Inc. The borings extended to 51 feet below ground surface (bgs). Soil cuttings contained 1,2-DCP, nitrate, nitrite, TKN, DDT, DDE, and DDD. Subsequently, two deeper borings were excavated near the original three. 1,2-DCP and nitrate were found in most of the soil samples from these borings. 1,2-DCP and nitrate were also found in the ground-water samples from these borings. Subsequent to this, approximately 15 cubic yards of soil contaminated with DDT were excavated to a depth of 12 feet from the oil-water separator area, and an additional 290 cubic yards of TPH- contaminated soil was excavated to a depth of 24 feet from the same area. In 1992, seven soil borings were drilled around the new tank farm. Samples collected were analyzed for nitrates and for halogenated volatile organic compounds. Only nitrates were detected. In 1993 four monitoring wells were installed and sampled by Condor Earth Technologies,Inc.(Condor). Soil samples were taken from the boreholes by both Condor and by E&E,Inc. under contract to EPA. Nitrates, 1,2,3- TCP and 1,2-DCP were detected in soil from the boreholes for wells MW-1 and MW-2. Only nitrates were detected in soil from the borehole for MW-3 (up-gradient). The soil from MW-4, which was located within the south pond, contained the pesticides Lindane, Heptachlor,Endosulfan,Endrin, DDT, and gamma-chlordane. The soil also had nitrates. In October 1994, Sierra-Pacific installed two offsite monitoring wells, approximately 300 feet west of the PureGro/Brea site, to determine if agricultural-chemicals have been transported down-gradient from the site by ground-water movement (Figure 3). Monitoring well MW-5 was installed five feet west of the centerline of Sutro Avenue, approximately 40 feet north of Lewis Street. MW-6 was installed five feet west of the centerline of Sutro Avenue, approximately five feet north of Charles Street. On September 18, 1995, Sierra-Pacific measured the water level and collected water samples at a solitary monitoring well located at 1705 North Broadway Avenue. The well (MW-11) is located about 200 feet south of the former PureGro/Brea site (Figure 3). MW-11 belongs to Geo F. Schuler, Inc_ and was sampled only one time due to access restrictions. Monitoring well MW-10 was installed at 1905 North i Sierra-Pacific Groundwater Consultants, Inc. o