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21 December 2017 <br />AGE-Project No. 14-3154 <br />Page 8 of 23 <br /> <br />Soil samples were collected from the base of the excavations under the waste at <br />the two identified waste cells. Samples from trenches T40, T43, T46, T58, T59, <br />T65 and T72 were analyzed for SVOCS, PAH, PCBs, dioxin and metals. SVOCs, <br />PCBs, and dioxins were not detected in the soil samples above reporting limits, <br />and various metals were detected in the soil samples at concentrations below the <br />DTSC-SLs and RSLs or at levels consistent with background concentrations in <br />California soils (Tables 1 – 3, and 5). A grab groundwater sample was collected <br />from T64, within the North Waste Cell. Low concentrations of residual TPH were <br />detected in the water sample from T64, below the buried waste (Table 6). <br /> <br /> <br />4.3. WASTE REMOVAL AND DISPOSAL <br /> <br />Between August and December 2015, soil and minor glass waste previously excavated <br />from the waste/glass handling area (during the mentioned trenching investigations) was <br />removed from the subject property, and wastes identified in the North and South Waste <br />Cells were excavated and removed from the subject property. The following is a summary <br />of these activities. <br /> <br /> Waste removal and disposal waste/glass handling area – August 2015: At the <br />direction of the LEA, native clean soil and minor glass waste removed by <br />exploratory trenching in April 2015 (T1 to T23) in the waste/glass handling area <br />was stockpiled on site and was not allowed to be used as backfill in the trenches. <br />Consequently, these materials were transported to Forward Landfill in Manteca, <br />CA for disposal in August 2015. Approximately 297 tons of waste glass, minor <br />garbage and native cover soils from the trenches were disposed. <br /> Waste excavations/removal/disposal North and South Waste Cells - September <br />2015: In September 2015, excavations were performed at the North and South <br />Waste Cells to completely remove the identified wastes in these areas of the <br />subject property. The North Waste Cell was excavated to a maximum depth of 13 <br />feet bsg and the South Waste Cell was excavated to a maximum depth of 10 feet <br />bsg. Figure 3 depicts the excavation aerial extent (area) and former limits of buried <br />glass/material waste. The excavations removed all the waste from the waste cells <br />and adequately defined the horizontal and vertical extent of the buried waste on <br />the property to the western boundary. Cross-sections of the two waste cell areas <br />are depicted in Figure 4. Prior to waste removal and during excavation of Trench <br />T64, shallow groundwater was encountered at the base of the North Waste Cell at <br />a depth of approximately 14 to 15 feet bsg. Low concentrations of TPH were initially <br />detected in the groundwater sample collected from T64 (T64-W) in September <br />2015. Therefore, following waste removal, three grab groundwater samples (C2 <br />NE/SE/NW-H2O) were collected in October 2015 from the base of the North Waste <br />Cell excavation, by re-excavated to expose sufficient groundwater for sampling. <br />The samples were collected at the direction of the CVRWQCB to evaluate the <br />potential impact from the removed waste on the groundwater, and to document the