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Domestic Well Sampling Program Results Forward Landfill gradient ranging from about 0.001 to 0.003 feet per foot (ft/ft), and a groundwater flow rate of about 0.7 to 2.1 feet per day(ft/day). In 1989, when owned by the City of Stockton, groundwater downgradient of the ARU was found to be impacted by chlorinated hydrocarbons. The ARU was purchased by Forward in 2000, and as a condition of that acquisition, Forward agreed to address any existing and potential groundwater contamination caused by the City's landfill operations, which go back to 1954. To date evaluation monitoring indicates that chlorinated hydrocarbon impacts extend as much as 7,700 feet downgradient of the Austin Road unit. The zone of groundwater affected by VOCs is shown in Figure 3 (the principal VOCs of concern include tetrachloroethene [PCE] and trichloroethene [TCE]). As shown in this figure, the limits of affected groundwater appear to be well-constrained both laterally and vertically on the east by wells AMW-5R,AMW-305 and AMW-30 and partially to the west by wells AMW-28, AMW-32S, AMW-32, and AMW-2. The zero line for the vertical and lateral extent of the plume has not been fully established to the northwest, north, and north-northeast. The overall shape of the VOC-affected plume with respect to groundwater contours and the distribution of VOCs between the shallow and deeper zones indicate the lateral and vertical limits of the VOC-affected groundwater have likely been affected by regional flow conditions (agricultural/industrial pumping, recharge rates,etc.). 2.0 SAMPLING AND ANALYSIS Between June 19 and 22, 2017, representatives from Geo-Logic Associates (GIA) visited the properties within the sampling area to ask permission from each resident to participate in the domestic well sampling program. If no one was home a participation notice (in English and Spanish) was left at the address. After receiving permission, groundwater samples were collected from fifty-six (56) residences between June 19 and July 6, 2017. Table 1 presents a summary of the residences that participated in the sampling program. Table 1 also includes the sample date, name of the resident/owner, if VOCs were detected,and any pertinent notes. Groundwater samples were collected in accordance with the approved Domestic Well Sampling and Analysis Plan. Before collecting the sample, the temperature, pH, and conductivity of the groundwater were measured and recorded on the well sampling data sheet that precedes the laboratory results. After these parameters were measured, a sample was collected for analysis of VOCs by EPA Method 8260B. Select residences on Newcastle Road were also analyzed for nitrate/nitrite (as nitrogen) by EPA Method 353.2. The groundwater samples were collected in laboratory-supplied sample containers, filled completely, immediately capped, labeled, and placed in an ice-filled cooler. A completed chain-of-custody form identifying the sample identification, date and time collected, and the analyses to be performed, accompanied each sample to BC Laboratories, a state of California certified laboratory located in Bakersfield, California. Project 5017.1030 I Domestic Well Sampling Program Results.docx 2 November 2017