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Fourth Quarter 2005 Groundwater Monitoring Report Eckert Cold Storage,Manteca,California February 27,2006 Page 3 Table 1–Groundwater Elevation Data ( January 5,2006) Monitoring Screened Interval(bgs) TOC Elevationi Depth to Water Groundwater Well Elevation MW-1 13-28 3809 1601 2208 MW-2 15-30 3790 1568 2222 MW-3 15-30 3831 — 1621 22 10 MW-4 12-27 3784 16 11 21 73 MW-5 14-34 4122 1935 2187 MW-6 13-33 3765 1544 2221 MW-7 13-33 3822 1607 2215 MW-8 17-37 377 1559 22 17 'TOC Elevation Elevations are measured from the top of the well casing and are referenced to NGS Benchmark HS4486,elevation 35 03 feet using NAVA 88 datum All measurements are in feet Histoncally, the groundwater gradient direction at the Site has been vanable but generally to the northwest The current groundwater gradient direction (northwest at a magnitude of 0 0029 ft/ft) is therefore generally consistent with historic gradient directions LABORATORY ANALYTICAL RESULTS . The groundwater samples collected on January 5, 2006 from monitoring wells MW-4,MW-5,MW-7, and MW-8 were analyzed for benzene, toluene, ethyl benzene, and total xylenes (BTEX) by EPA Method 8260B, total petroleum hydrocarbons quantified as gasoline (TPH-G) by EPA Method 8015M, and selected gasoline oxygenates/additives including methyl tertiary butyl ether (MTBE) by EPA Method 8260B The current analytical results are shown in Table 2, on the next page Prior to the December 2004 monitoring event, historic laboratory analytical results of groundwater samples collected from MW-5 indicated generally very low contaminant concentrations Laboratory analytical results of samples collected from MW-5 in December 2004, January 2005, and March 2005 indicated higher contaminant concentrations (but with a decreasing trend in contaminant concentrations) Laboratory analytical results of groundwater samples collected from monitor well MW-5 during the July 2005 monitoring event indicated that contaminant concentrations had returned to very low levels The Previous (September 2005) and current laboratory analytical results indicate that these very low levels have continued(see historic groundwater monitoring data, Attachment C) Conversely, prior to the December 2004 monitoring event, historic laboratory analytical results of groundwater samples collected from MW-8 indicated generally elevated contaminant concentrations Laboratory analytical results of samples collected from MW-8 in December 2004, January 2005, and March 2005 indicated lower contaminant concentrations relative to the histone results Laboratory analytical results from the July 2005 monitor event indicated that contaminants in MW-8 had increased back to the relatively higher concentrations consistent with samples from the well collected prior to December 2004 Previous (September 2005) contaminant concentrations detected in MW-8 indicated that contaminant concentrations had returned to the low levels relative to historic results, and the current laboratory analytical results indicate that these very low levels have continued (see histone • groundwater monitoring data,Attachment C) } tM to CONDOR