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i kTJ KLEINFELDER 1,2-DCA was detected in MW-DIS-11s, MW-DIS-12, MW-DIS-14s, and MW-DIS-15 at concentrations of 7 ug/l, 1.7 ug/l, 1.4 ug/1 and 1.0 ug/I, respectively. A continued decreasing trend was noted from previous results in MW-DIS-14s and MW-DIS-15; while the concentration of 1,2-DCA in MW-DIS-11s (7 ug/1) remained similar to the concentration detected last quarter (8 ug/l), and much less than the previously detected concentration of 200 ugll previously detected during the fourth quarter 2004. There were no other analytes detected in the remaining wells sampled this quarter. Oxygenates MTBE, DIPE, ETBE, and TAME (only analyzed from MW-DIS-15) showed non-detectable concentrations at or above the laboratory reporting limits. This quarter MW-DIS-9 was sampled due to a recent groundwater flow direction shift towards the east. The groundwater flow direction had previously been towards the southeast. MW-DIS-9 is located directly east of the former UST's and remediation facility. The sample collected from MW-DIS-9 showed non-detectable concentrations of TPH-g, BTEX, TBA, 1,2-DCA and EDB. The three piezometers sampled this quarter (NP1-70', NP1-80', NP1-90') showed increased or steady concentrations of TPH-g, ethyl-benzene, and xylene compared to last quarter. The 1,2 DCA concentrations increased slightly in NP1-90' and NPI-70'; and decreased in NPI-90'. The benzene concentrations in NP1-90' and NPI-80' decreased and remained the same as the last quarter in NP1-70'. The samples showed non-detectable results for the fuel oxygenate TBA. The EDB concentrations in the piezometer NP-90' decreased this quarter, and in NP-80' and NP-70' the EDB concentration increased. Due to the recent groundwater flow direction shift towards the east (recorded during the fourth quarter 2004), Kleinfelder requested from Del Monte and was granted permission to conduct a water well survey within a 2,000-foot radius of the site to evaluate whether any new wells have been installed and are pumping. The Department of Water Resources (DWR) was contacted and available records were reviewed. The results of the well survey showed no new wells drilled, nor multiple wells pumping near the site within a 2,000-foot radius. The seasonal fluctuations of groundwater elevations may be linked to naturally occurring rainfall/recharge, and/or other groundwater extraction practices near the site. In areas of such flat gradients, slight changes in groundwater elevations can affect the groundwater flow directions. The groundwater elevation range at the site typically is less than a foot. GROUNDWATER TREATMENT SYSTEM OPERATION The soil vapor extraction system installed by CH2M Hill was replaced by Kleinfelder during 2003 with an air sparging (AS)/high vacuum soil vapor extraction (SVE)/ozone injection system. The ozone injection system began consistent operation within the downgradient portion of the plume in September 2003. The system has only been inoperable during periods of system maintenance and enhancements. 12280.M0NIST05R14241CD:Iv Page 2 of 14 ©2005, Kleinfelder, Inc. November 15,2005 I