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As-Built CQA Report for the Construction of Area 2A at the Foothill Sanitary Landfill San Joaquin County,California • 8.0 OPERATIONS SOIL LAYER 8.1 GENERAL R. J. Gordon placed a total of approximately 43,000 cubic yards of operations layer soil on the floor, the side slopes and the bench between Area 2A and Area 1. The materials used for operations layer consisted of on-site material screened through a 1-inch screen, using a Power Screen. The maximum particle size of operations layer soil was relaxed from minus 3/8-inch to 1 inch for the lower 1 foot (above geomembrane) as discussed in Section 1.5 of this report. The contractor used minus 1-inch material for the entire 2-foot thickness of operations layer. 8.2 CQA GRADATION TESTING OF OPERATIONS LAYER SOIL Gradation tests were performed in the field and in the geotechnical laboratory (AP Engineering) during stockpiling,screening and placement to verify conformance with the Project Specifications. CQA Testing During Selective Stockpiling: Relatively sandy material from excavation was placed in a separate stockpile designated for operations layer. Representative field gradations (minus #200) were performed during stockpiling, to assist the contractor in identifying suitable sandy materials. These results are included in Appendix E.6a. Material finer than No. 200 sieve ranged from 10 to 31 percent. • CQA Testing During Placement. Representative samples of placed operations layer materials were tested for gradation analysis. A total of 23 field gradations and 6 laboratory gradations were performed from screened stockpile and in-place materials. Results are included in Appendix E.6b. All material passed through the 1- inch screen and the material finer than No. 200 ranged from 3 to 20 percent. 8.3 PLACEMENT Placement of the operations layer was performed by careful use of construction equipment so as to avoid damaging the geocomposite on side slopes or geotextile on the floor. For the side slopes, the material was first stockpiled in windrows near the toe of slope and pushed up with LGP dozers to 20 linear feet measured along the slope from the toe. Operations layer soil along the upper portions of this limit were placed after the completion of sacrificial geomembrane installation. Placement was monitored to verify that a minimum 1 foot of material was always maintained under the LGP dozer tracks. A CAT 745 articulated truck hauled material from stockpile to areas of completed operations layer adjacent to the placement area. A CAT D6T LGP equipped with GPS was used to spread the material into place in a 2-foot thick lift on the floor. Similar method and equipment was used to push the material onto the side slopes in a 2-foot thick lift. The surface was later track- walked with the CAT D6T dozer.A water truck added moisture as needed. Placement of operations layer was observed full time by a CQA Monitor. No compaction test was performed as it was not • required by the Specifications. PA14 Projects114-101(SJCDPW North County and Foothillffoothill CQAIReportTinal ReportToothill CQA Rport-Final.docx 33