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<br />P:\Projects\0106.071 2025 Resident\J-REPORTS\VLF2 P3 Stage B.1 <br />RoC Page 11 <br />trucks to haul DCFO from the stockpile to the VLF2 Phase 3 Stage A.2 project area. The <br />DCFO was placed in a minimum 2-foot-thick layer over approved 80-mil using approved <br />Low Ground Pressure dozers. The DCFO as-built is shown on Record of Construction Drawings <br />Number 5. <br />The haul routes were initially constructed with 4-foot lifts, which were subsequently reduced to <br />2-foot lifts during final grading of the area. All DCFO was placed in an uphill direction on slopes <br />steeper than 4H:1V, and grading was verified using dozers with GPS technology. <br />A CQA Monitor was present during all DCFO placement activities to verify that the DCFO was <br />placed in accordance with the project Technical Specifications and that no damage to the <br />geomembrane occurred. If any damage to the geomembrane was noted, work activities were <br />paused, and the damage was repaired prior to resuming DCFO placement. The DCFO as-built <br />isopach is presented on Record of Construction Drawing Number 6. The DCFO isopach was <br />created by calculating the volume surface between two layers: the top of the SLF and the top of <br />the DCFO. Survey points were used to develop both the SLF and DCFO surfaces, though the points <br />for each surface were not always collected at identical locations. Depths reported as less than 2 <br />feet likely had errors resulting from triangulation between survey points. Any areas identified as <br />low spots were measured manually and confirmed in the field by NewFields to verify a minimum <br />depth of 2 feet. If a low spot was identified in the field, the contractor was informed and <br />additional material was placed to meet the 2-feet minimum requirement. <br />2.7. 80-mil Anchor Trench <br />The geomembrane was anchored at the northern and southern limits of the VLF2 Phase 3 Stage <br />B.1 area in a minimum 2-feet-wide and 3-feet-deep anchor trench or 3-feet-wide and 2-feet deep <br />anchor trench. The eastern limits of geomembrane on the 10,325-foot elevation bench of B.1 <br />was secured within a 2-feet-wide and 3-feet-deep anchor trench. The anchor trench was <br />backfilled by JHL using a mini excavator and skid steer. The backfill material, which was composed <br />of SLF and rejected material from the SLF screening plant, was placed in 8 to 12-inch loose lifts <br />and compacted with a mini excavator with vibrating plate attachment. In areas where future <br />geomembrane installation would cover the anchor trench, SLF was used to backfill the top 12 <br />inches of the anchor trench. <br />3. CONSTRUCTION QUALITY ASSURANCE/CONSTRUCTION QUALITY CONTROL <br />CQA and CQC activities were performed by NewFields CQA for all shifts during the VLF2 Phase 3 <br />Stage B.1 project. An office and field laboratory were used to organize data and perform <br />necessary laboratory testing onsite. CQA and CQC activities performed included: monitoring all <br />aspects of construction, inspection and approval of all project components, laboratory testing of <br />soils and geomembrane, field testing of soils and geomembrane, documentation of construction, <br />and CQA and CQC activities.