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The groundwater data showed 270,000 parts per billion (ppb) TPHD and 270 ppb TPHG { in groundwater from B-1 drilled through the former tank pit. B-2 showed 17,000 ppb TPHD, with TPHG and BTEX not detected. Boring B-3 revealed low concentrations of TPHD and TPHG, with Xylene detected at 1.9 ppb. Trace concentrations just over the detection limit of Ethylbenzene and Xylene were observed in B-1. MTBE and oxygenates were not detected in any groundwater water sample. Only TPHD was detected in downgradient boring B-4 and assumed side-gradient boring B-5. The laboratory reports that TPHD did not match the diesel standard for soil data, and both TPHD and TPHG in groundwater samples did not match the laboratory gasoline or diesel standards. In our opinion, ,these data strongly suggest a fuel in a highly degraded state. f July, 2001 Soil and Groundwater Data The soil and sediment samples collected from the push borings showed that contaminants were not detected. Th'e reconnaissance groundwater samples also showed that 11 contaminants were not det cted in boreholes except at B-6 where 120 milligrams per liter TPHD were observed. Groundwater well samples showed that only MW-3 revealed contaminants at 440 TPHD and 58 TPHG respectively) Wells MW-1 and MW-2 showed that contaminants were not detected. The water well is sealed from 0- to 50-feet and the intake screens occur below 101-feet tapping an aquifer separated from the uppermost shallow aquifer by clay beds at 29- to 35-feet and 45- to 60-feet!,(see DWR Water Well Drillers Report No. 219475). These deeper clay beds are interpreted to act as confining layers separating the uppermost aquifer (between 15-and 26-feet) and the deeper pumping aquifer tapped by the Water Well. The well seal occurs across the clay beds at 29- to 35-feet and extends five feet into the 45- to 60-foot clay bed. Logging data from Boring B-10 shows that this clay aquitard in present and di'd not yield water from depths of 26-to 46-feet. Soil sample chemical analysis from B-10 show that contaminants were not detected, therefore contaminants are not interpreted as migrating vertically through these strata toward the Well. Water Well Sample Data-Discussion of March, 2000 and July, 2001 Data Only TPHD was detected in the Water Well at 69 ppb,just over the detection limit. The detection of TPHD was the only contaminant present at a concentration just over the detection limit. The laboratory reports that this contaminant did not match their diesel standard. In our opinion;) the assessment data do not initially indicate the uppermost. shallow aquifer as a source of this contaminant. It is not known whether this well is equipped with a self-oiling)pump, which could be a possible contaminant source. Neither on-site or well owner personnel have reported any water problems to Wright. V Page 6