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be used to grade the lower areas of the quarry. The haul trucks or scrapers will transport the <br /> material to the reclamation slope and place the fill in lifts. Imported fill material will be dumped on <br /> the quarry floor by the delivering contractor, and the site crews will move the material to the <br /> reclamation slope. <br /> Upper Slope Grading <br /> Steep slopes near the top of the quarry will be graded to promote slope stability and reclamation. <br /> Non-native slopes with existing wall angles steeper than 0.5H:1 V, or overall slope angles steeper <br /> than 1 H:1 V, will be excavated into rock utilizing standard benching practices not to exceed 40 <br /> vertical feet. While minimizing loose and unconsolidated material from the face, competent rock <br /> outcrop slopes will be achieved at an overall slope of 1 H:1 V with 30' to 40' benched slopes. <br /> Interbench slopes will be constructed at a 0.5H:1V gradient. In an attempt to minimize additional <br /> disturbed lands, bulldozers will push materials down slope to create the backfill slope. Each bench <br /> will be covered with fill and topsoil and then revegetated. The remaining highwall slopes will be <br /> left as bare rock. The benched slopes are expected to be less than 200 feet tall, and the areas <br /> of benching are shown on the maps in Exhibit C. <br /> Lower Borrow Area Grading <br /> Multiple areas on the lower quarry contain stockpiles or steep slopes, and these areas will be <br /> graded for reclamation. Each will be excavated to construct the reclamation topography, and <br /> excavated material will be used to backfill the quarry and create the backfill slope. The steep <br /> slopes along the road used to access the shop will be graded to a 3H:1 V slope while leaving light <br /> vehicle access for future monitoring of slope and vegetation conditions. This grading will remove <br /> the maintenance shop and security/office buildings and their foundations along with any rock <br /> stockpiles or non-native slopes which exceed the approved slope recommendations. The <br /> foundations will be broken-up and buried in the backfill. Other areas will also be graded to 3H:1 V <br /> slopes or flatter. The lower borrow areas are shown on the maps in Exhibit C. <br /> Slope Backfill Grading <br /> The quarry slopes will be backfilled, from bottom-up, using material excavated from the lower <br /> borrow areas and material imported from offsite. Fill material will be placed at the toe to buttress <br /> and regrade the slope at a 2.25H:1 V below the 7560 elevation and 2H:1 V above 7560. Fill material <br /> from major borrow sources (greater than 100,000 cubic yards) will be sampled and analyzed by <br /> a geotechnical laboratory for important geotechnical properties including: shear strength, particle <br /> size distribution, and standard proctor density. This material will be placed in lifts and compacted. <br /> Moisture conditioning (based on standard proctor results) and truck and bulldozer traffic are <br /> expected to provide sufficient compaction of the fill material to achieve at least 90% standard <br /> Pikeview Quarry Amendment 4 <br /> 2019 <br /> D-3 <br />