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Page 5 <br /> Mr Michael Infurna Jr, Senior RENS <br /> January 20,2004 <br /> January 2004 Groundwater Monitoring <br /> On January 7, 2004, Kleinfelder, Inc (under PESC's direction) collected <br /> groundwater samples from the four existing monitoring wells (MW-1 through <br /> MW-4) Prior to sampling, Kleinfelder's geologist measured groundwater levels <br /> within the wells with an electronic well sounder, checked for potential free phase <br /> petroleum product, and then purged a mimmum of three well volumes from each <br /> well with clean, disposable bailers Free phase petroleum product was not <br /> observed in any of the wells Temperature, pH, and electrical conductivity <br /> parameters were also measured during the purging process to assess groundwater <br /> stability Purged groundwater was placed in one 55-gallon drum and temporarily <br /> staged on-site pending proper disposal <br /> Groundwater samples were collected from each well with its own dedicated <br /> bailer Samples were placed in clean, laboratory-provided glass containers, sealed, <br /> labeled, and stored in an insulated iced chest Samples were delivered to Severn <br /> Trent Laboratory in San Francisco, California, accompanied by chain-of-custody <br /> documentation, for chemical analysis Samples were analyzed for BTEX and <br /> TPHg compounds using EPA Method 602/8015 Samples were also analyzed for <br /> oxygenate compounds tert-butanol (TBA), methyl-tert-butyl ether (MTBE), <br /> di-isopropyl ether (DIPE), ethyl-tert-butyl ether (ETBE), and tert-amylmethyl <br /> ether (TAME) using EPA Method 8260B <br /> Groundwater Level Measurements <br /> As shown in Table 2, groundwater within the monitoring wells were measured at <br /> depths approximately 1 7 feet deeper than the previous round of monitoring <br /> performed in April 2003 Groundwater depths ranged from 28 42 feet (below the <br /> top of the well casing) to 29 35 feet Depth to groundwater in well MW-2 is not <br /> considered applicable at this time because it may have been altered due to venting <br /> operations The corresponding groundwater elevations, evaluated during this <br /> monitoring period, ranged from minus (-)18 87 feet to—19 59 feet relative to <br /> mean sea level As shown in Figure 3, groundwater flows easterly at an <br /> approximate gradient of 5 0 x 10"3 feet per linear foot, which is generally <br /> consistent with historic trends <br /> Y Groundwater Sample Analytical Results <br /> Petroleum hydrocarbon concentrations were not detected in the samples from <br /> monitoring wells MW-1, MW-3 and MW-4 Petroleum hydrocarbon <br />