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Upon placement, if test results indicate a relative dry density of less than 90 percent of the maximum dry density as determined by ASTM D1557 or a moisture content outside of the specified limits (2 percent above or below optimum moisture content), then two additional field density/moisture content tests will be conducted in the immediate area. If either of these tests fail to meet the moisture content or 90 percent minimum compaction requirements, the area will be considered inadequate and will be'reworked. Any reworked areas will be retested by the CQA Monitor to assure the reworked area meets the density and moisture content requirements. For soils placed closer than one foot to waste, a relative density of slightly less than 90 percent of the ASTM D 15 57 maximum dry density may be approved if, in the opinion of the Geotechnical Consultant, the yielding nature of the underlying refuse prism, creates a situation where the minimum required density cannot readily be achieved. In no event will the minimum density requirement of the remainder of the cover system be modified. 6.3.3 GRAIN SIZE DISTRIBUTION For grain size distributions completed during during placement of the four-foot thick final cover section, no individual test resulting in a value of less than 70%passing the no. 200 sieve and no individual test resulting in a value less than 30%passing the 5-micron sieve will be acceptable. If inadequately mixed materials are placed, the Contractor shall immediately reprocess these materials or remove them from the construction site. • 6.3.4 HYDRAULIC CONDUCTIVITY If field or laboratory hydraulic conductivity tests (ASTM D5084 or modified USBR E 9600) completed in the three-foot thick final cover section result in a value exceeding 1.0x10-6 cm/sec, two (2) additional tests of the same type will be taken in the immediate vicinity of the test yielding the unacceptable hydraulic conductivity. At the discretion of the Geotechnical CQA Consultant, field permeability tests may be taken in lieu of failed laboratory tests to expedite the CQA testing procedure. If either of the additional tests fails to meet the minimum average test requirements, the area represented by the tests will be considered inadequate and will be removed or reprocessed and recompacted. 6.3.5 LIFT THICKNESS AND PROCESSING If at any time the CQA Monitor observes an uncompacted lift thickness in excess of six- to eight-inches or observes materials being placed without the required processing, the Contractor shall immediately discontinue placing additional fills in that area. For an over thick lift, the Contractor shall immediately blade the surface to reduce the lift thickness to project specifications prior to compaction. If inadequately mixed materials are placed, the Contractor shall immediately reprocess these materials or remove them from the construction site. • -14- CLA/2005-0082/FOR W ARD/CQAPLAN.d od7/15/2005 Geologic Associates