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® Trend analysis of VOC concentrations indicates increasing trends for Dichlorodifluoromethane, <br /> PCE and Freon 11. Trend analysis also indicated a decreasing trend in TCE is quarter. Trend <br /> analysis will continue to be used quarterly to evaluate concentrations of VOCs in MW-8. <br /> MW-9A (Newly-installed): <br /> This is the fourth quarter MW-9A was monitored. Concentrations of all parameters were within <br /> established concentration limits where the limits 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 /> This is the fourth quarter MW-10A was monitored. Concentrations of all parameters were within <br /> established concentration limits where the limits could be determined(Table 1). <br /> One VOC was reported above PQL this quarter, two at"trace" concentration (Table 1). <br /> All VOCs detected in this well are among the VOCs found in MW-5 and MW-8, at lower <br /> concentrations. It is our opinion that MW-5 is closer to the source of the VOCs and thus has more <br /> VOCs. <br /> Data is not sufficient to establish a trend in this well. <br /> -IIA (Newly-installed,Impacted): <br /> This is the fourth quarter MW-11A was monitored. Concentrations of all parameters were within <br /> established concentration limits where the limits could be determined(Table 1). <br /> One VOC was reported above the PQL,three were reported as "trace"this quarter(Table 1). <br /> All VOCs detected in this well are among the VOCs found in MW-5 and MW-8, generally at <br /> lower concentrations. The higher concentration of VOCs at MW-5 indicates that it is closer to the <br /> source of VOCs. <br /> 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 <br /> ® • The PCE concentration detected at MW-1 IA (0.26 ug/L) is slightly above the laboratory <br /> method detection limit of 0.13 ug/L <br /> Conal Hollow Sanitary Landfill 14 Department of Public Works/Solid Waste <br /> 1s`Quarter 2013 Groundwater Monitoring County of San Joaquin—April 15,2013 <br />