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concentrations with 0.0057 parts per million (ppm) Xylene detected. Boring B-2 showed 83 ppm TPHD with all other contaminants not detected. Only 0.4 ppm TPHD(just over the detection limit)was detected in the deeper underlying confining strata soil sample at B-1. The B-2 underlying confining strata sample (also advanced through the former tank pit) showed that no contaminants were not detected(see Figure 3). Shallow Groundwater Data-Discussion 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 TPHD laboratory reports did not match the diesel standard for soil data. 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. These data appear to indicate that previous soil excavation removed petroleum contaminants although low concentrations of highly degraded contaminants remain. Ethylbenzene and Xylene were the only volatile components detected at extremely low concentrations. Benzene, Toluene, and MTBE and oxygenates were not detected in any sample. The relatively high dissolved TPHD present at B-1 and B-2 could represent absorbed degraded fuel in the capillary fringe area which was released by the drilling or push action when sampled from the borehole. Water Well Data-Discussion TPHD was detected in the Water Well at 69 ppb,just over the detection limit. This 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 and deeper pumping aquifer tapped by the 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. 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. Conclusions and Recommendations Five borings were advanced in and around the former tank pit areas at M&M Builders. The soil and groundwater sample data show that low levels of degraded TPHD occurred in capillary fringe soil samples. Dissolved TPHG was observed at B-1, and dissolved TPHD contaminants were observed at B-1 and B-2, with lower TPHD concentrations at B-3, B-4 and B-5. Only trace levels of Ethylbenzene and Xylene were detected in B-1 and B-3. Neither MTBE nor oxygenate contaminants were observed in any groundwater sample.