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�� F�rur Working To Restore Nature Nor-Cal Beverage Company Project No. 150005.01 Page 2 below grade. Analysis of a groundwater sample collected in June 1991 indicated 100 parts per billion (ppb) TPHG and 1.6 ppb benzene (Table 2). Well MW-1 was resampled in September 1991. Duplicate samples were sent to two separate laboratories. Analytical results are summarized in Table 2. In January 1992, two soil borings were drilled through the backfill of the previous excavation. Boring locations are shown on Figure 2. No analytes were detected in samples collected from boring B-1. Groundwater was also monitored and sampled in January 1992. The depth to water was approximately 69 feet below grade, which was consistent with previous monitoring events(Table 3). The groundwater sample was analyzed for BTEX and TPHG. No analytes were detected (Table 2). . In May 1993, residual petroleum hydrocarbon contaminated soil was excavated from the two remaining areas of impacted soils identified during previous excavation and drilling activities. Confirmation samples were collected from the sidewalls and floor of the excavation. The extent of the excavation and sample locations are depicted on Figure 2. Samples were analyzed for BTEX and TPHG. None of the analytes were detected in any of the samples (Table 1). On July 13, 1993, the depth to groundwater in the existing on-site well (MW-1, Figure 2) was measured to be 69.46 feet below grade. This depth is consistent with previous monitoring events (Table 3). A groundwater sample was collected and submitted for analysis of TPHG and BTEX. Analytical results are summarized in Table 2. No benzene or TPHG was detected. On July 16, 1993 a single hydropunch boring was advanced north-northwest of the former tank excavation (Figure 2) under the direction of Ms. Diane Hinson of PHS/EHD. The boring was advanced by hollow-stem auger to approximately 70 feet below grade. The hydropunch tool was then driven four feet into the saturated zone and a groundwater sample was collected. The sample was submitted for analysis of TPHG and BTEX. None of the analytes were detected. Laboratory results arep resented in Table 2. WELL LOCATION SURVEY The site is situated on level terrain underlain by flood basin deposits of Pleistocene and Holocene age. These sediments are composed of clay, silt, and some sand. In the San Joaquin Valley, . the Flood Basin Deposits (Holocene) have been estimated to be as much as 100 feet thick (USGS Prof. Paper 1401-C, 1986). Because of their fine-grained nature, the flood basin deposits 41293.FNi 2