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0 <br />11 <br />d <br />h <br />analysis of VOC concentrations indicate increasing trends for 1 1-Dichloroethane, <br />Trend y g <br />Dichlorodifluoromethane, PCE and Freon 11. Trend analysis also indicated a decreasing trend in <br />TCE is quarter. Trend analysis will continue to be used quarterly to evaluate concentrations of <br />VOCs in MW -8. <br />AIW-9A (Newly -installed): <br />This is the sixth quarter in which MW -9A and the other off-site wells were monitored. <br />Concentrations of all parameters were within established concentration limits where the limits <br />could be determined (Table 1). <br />No VOCs were reported in MW -9A this quarter (Table 1). <br />Data is not sufficient to establish a trend in this well. <br />MW -10A (Newly -installed, Impacted): <br />. Concentrations of all parameters were within established concentration limits where the limits <br />could be determined (Table 1). <br />Three VOCs were reported this quarter, two above PQL and one below the PQLat "trace" <br />concentration (Table 1). <br />All VOCs detected in this well are among the VOCs found in MW -5 and W-8, but at lower <br />concentrations. These data support the conclusion that M-5 is closer to the source of the VOCs. <br />Data is not sufficient to establish a trend in this well. <br />-11A (Newly -installed, Impacted): <br />Concentrations of all parameters were within established concentration limits where the limits <br />could be determined (Table 1). <br />Two VOCs were reported above the PQL this quarter (Table 1). This is a significant improvement <br />from last quarter, in which five VOCs were reported; however, such a conclusion must be <br />tentative. The County will carefully review future monitoring to assess if this is the beginning of a <br />significant trend. <br />All VOCs detected in this well are among the VOCs found in MW -5 and MW -8, generally at <br />lower concentrations. These data support the conclusion that MW -5 is closer to the source of the <br />VOCs.Data is not sufficient to establish a trend in this well. <br />Extent of Groundwater Impact Delineated <br />The area of groundwater impact apparently extends northeast to a maximum distance of <br />approximately 900 feet from the landfill property (Figure 5). The extent of groundwater impact is <br />delineated based on the following evaluation of PCE concentration, as follows: <br />• No PCE detected at MW -9A and MW -11A <br />Corral Hollow Sanitary Landfill 14 Department of Public Works/Solid Waste <br />3' Quarter 2013 Groundwater Monitoring County of San Joaquin — October 15, 2013 <br />