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3.2 Water Sample Analysis <br /> Groundwater samples were analyzed for total petroleum hydrocarbons (TPH) as gasoline _ <br /> in accordance with 8015m and volatile aromatics (BTE&X) in accordance with EPA method <br /> 602 <br /> 4.0 FINDINGS - <br /> 4.1 Groundwater Elevation <br /> The relative groundwater elevations for the monitoring wells were calculated by subtracting <br /> the water depth from the casing elevation (Table 3) Comparison of January 1994 with <br /> October 1993 indicates that water levels have risen approximately two feet in all wells, <br /> reversing the drop from June to October The rise and fall of the groundwater levels is <br /> expected due to seasonal variations in groundwater recharge <br /> 4.2 Groundwater Flow Direction and Gradient <br /> As with previous sampling events, the water level is highest in MW-3 and groundwater flow <br /> continues to be to the east The current hydraulic gradient is 0 00032 ft/ft oriented due east <br /> (Figure 5) <br /> 4.3 Groundwater Sample Analysis <br /> Benzene, toluene, and xylene were detected in MW-3 at 13 µg/L (ppb), 2 1 ppb, and 11 <br /> ppb, respectively No petroleum hydrocarbons were detected in the samples collected from <br /> MW-1 and MW-2 The analyti6al results from MW-3 were determined to be <br /> unrepresentative based on previous quarterly sampling episodes (Table 4) All previous <br /> water samples in MW-3 have been below detection levels At the request of GeoAudit, <br /> Sparger Technology, Inc reanalyzed water sample MW-3 No petroleum hydrocarbons were <br /> detected in sample MW-3 Laboratory reports (STI Lab ID #ST94-01-691A and ST94-01- <br /> 324A) and chain-of-custody are included in Appendix D <br /> 5.0 CONCLUSIONS & RECOMMENDATIONS <br /> In the March 1993 sampling event, low levels of benzene and xylene were detected in MW- <br /> 2 However, the contamination was not confirmed in the June or October 1993 sampling <br /> events, and may not be representative In the January 1994 event benzene, toluene, and <br /> xylene were initially reported in MW-3, but re-analysis of the sample did not confirm the <br /> presence of detectable hydrocarbons <br /> 0-bt-1 Aud.,S-- Inc 13 <br /> 1.614�d G1 OR <br />