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28 February 2005 AGE-NC Project No. 97-0327 Page 3 of 4 ' 3.2. ANALYTICAL RESULTS OF MONITORING WELL WATER SAMPLES A total of four ground water samples were submitted to CAL TECH Environmental Laboratory ' (CTEL),a DHS-certified laboratory,for analysis. TPH-g,TPH-d,BTEX compounds,and fuel oxys MTBE, TBA, DIPS, ETBE, TAME, and EDB were not detected in any ground water samples collected. 1,2-DCA was the only analyte encountered above laboratory detection limits;it was found in MW-4 only at a concentration of 5.4 ug/L. Analytical results of the ground water samples are summarized in Tables 3 and 4. The laboratory reports (CTEL reference No. CT214-0510147) and chain-of-custody forms are presented in ' Appendix B. -GEOTRACKER PHRASE INSERT- 3.3. ANALYTICAL RESULTS OF DOMESTIC WATER WELL SAMPLES Grab water samples were not collected from off-site domestic water wells located at 451 and 452 • North Lillian Avenue during this quarterly monitoring event. ' 4.0. SUMMARY AND CONCLUSIONS ' The implications from the October 2005 ground water monitoring event are as follows: • Ground water flow direction at the site was inferred to be toward the south at a gradient of ' 0.001 ft/ft or less;previous ground water monitoring events at the site have determined the prevalent ground water flow direction to be towards the south-southeast. • Due to the low gradient at the site, slight variations in ground water measurements or changes of recharge/discharge of the local ground water could have modified ground water flow direction. ' The ground water elevation at the site was within the screened intervals of wells MW-1, MW-2, MW-3 and MW-4, which should yield samples fully representative of shallow ground water conditions. - .—While--,1,2;.DCA----was the-only=target analyte-detected-above laboratory reporting limits (5.4 ug/L in MW-4), the annual variability of contaminant concentrations (Table 2 and 3) suggests an unstable plume. Advanced GeoEnvironmentai,Inc. 1 .