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21 December 2017 AGE-Project No. 14-3154 Page 11 of 23 8.0. POST REMEDIATON/VERIFICATION TRENCHING Twenty-five (25) additional trenches (T111 through T136) were established on 06 and 07 November 2017. The trenches were directed by the LEA in coordination with the CVRWQCB to: verify and further confirm the lateral extents of the waste/glass handling area; to determine the soil type and depth of any additional buried waste at the site; and, to collect additional samples (soil and waste) for analyses that were not conducted on samples collected from previous trenches. A total of eight (8) trenches (T111 through T114, T116, T117, T125, and T135) were established within the former waste/glass handling area and along the outer edges of the area. Trenches T117, T125 and T135 were established within the waste handling area in locations to duplicate trenches T11, T15 and T16 (Figure 2). Samples of the glass waste and binding materials, as well as soil beneath the waste was collected for chemical analysis. Trenches T111, T112, T113, T114 and T116 were established along the outer edges of the waste handling area in each direction to precisely define the exact limits of the waste buried under native soil cover and to document the cover thickness (Figure 2). These trenches were established to approximately 11 to 12 bsg. The work further allowed the LEA and AGE to re-verify the total depth of buried waste in this location at the site and to make visual observation of the contact with native soils (Figure 2; Appendix B). The remaining trenches (T115, T118 through T124, T126 through T134, and T136) established in November 2017, were in the south, east and southeast portions of the irrigation field on the site to determine the soil type and to confirm the absence of wastes in these areas. No waste was encountered in any of these trenches. Native soil consisted of tan, brown- to dark-brown silts and sands and local hardpan soils were encountered between surface grade and approximately 12 feet bsg; no odor was observed in the soils encountered in the trenches. Soil samples were also directed to be collected by the LEA and analyzed for the chemicals of concern. Groundwater was observed at 12 feet bsg in the deeper trenches located in the eastern irrigation field (Figure 2). 8.1. ANALYTICAL RESULTS OF SOIL SAMPLES Chemicals of concern, except CAM17 Metals, were not detected above laboratory reporting limits in any of the soil samples collected beneath the waste and in the irrigation field. Various metals were detected in the soil samples at concentrations below the DTSC- SLs and RSLs or at levels consistent with background concentrations in California soils (Tables 1 and 5). Samples of the glass waste were collected and analyzed from trenches T117, 125, and 135 (within the waste/glass handling area). The following is a summary of the analytical results:  SVOCs and PCBs were not detected above reporting limits in the waste samples (Table 5).