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Aggregate Industries, Morrison Quarry Amendment No. 7 to Permit M-1973-021 Morrison, CO October 2021 | 37 stressed vegetation, anomalous topography, surficial debris, suspicious pipes, and other structures will be recorded and evaluated. Debris and recyclable materials are to be disposed of in accordance with Item 7.0. The operator is to ensure that sites are leveled and backfilled to adjacent ground level and revegetated according to Items 10.0 and 11.0. Any fill required will be generated from onsite materials or furnished by an off-site source and must be clean, compactable fill. All disturbed areas must be graded and raked free of debris. Exhibit L – Reclamation Costs provides costs for dismantling and demolishing structures. Item 7.0 Debris Removal This item covers off-site disposal of debris materials that are encountered during Item 6.0. This task assumes up to 40 truckloads (10 tons/load) will be hauled from the site to a licensed disposal facility. Debris is considered to be non-contaminated and non-hazardous, consisting mostly of construction materials (concrete, rebar, lumber, drywall) and recyclable metal scrap materials. Item 8.0 Mined Areas Earthwork Once the site controls are installed, the grading plan for mined areas will be implemented. All areas will be appropriately marked to protect vegetation and structures to remain. The reclamation work areas will then be cleared and grubbed prior to excavation and backfilling. Available topsoil sources within the earthwork area will be stripped and appropriately stockpiled. Fill slopes in the upper highwall areas (southwestern corner) of the North Quarry will be placed and compacted to achieve a 2-foot cover sloped between 2H:1V and 20H:1V. Compaction will be performed with tracked equipment (D9 bulldozer) performing a minimum number of passes to achieve specified densities. The North Quarry additional fill area is estimated to require a minimum aggregate fill volume of 3,227 cubic yards if no additional byproduct material is used for fill. Fill slopes on the 60-foot-wide benches of the South and West Quarries (above El. 7,000) will be placed and compacted to achieve 2H:1V slopes, with 5- to 10-foot-wide benches and rockfall catchment berms every fourth bench. On normal benches where no catchment berm is placed, the fill will be a maximum 30 feet thick at the highwall, and roughly 10 feet of the rock face will remain exposed. Trees and woody debris structures will eventually cover many of these exposed faces. Compaction will be performed with tracked equipment (D9 bulldozer) performing a minimum number of passes to achieve specified densities. The South and West Quarries (above El. 7,000) are estimated to require aggregate fill volume of 136,380 cubic yards. Fill slopes on the lower highwall areas with 40-foot benches (below El. 7,000) will be placed and compacted to achieve an average slope of 10H:1V, but range from 2H:1V to 20H:1V. Rockfall catchment berms roughly 5- to 10-foot-wide will be placed every fourth bench above 7,000 feet. On average benches the fill will be approximately 4 feet thick at the highwall, and roughly 36 feet of the rock face will remain exposed. To provide slope variability, some benches may have fill resembling the upper 2H:1V slopes, while others may only have 2 feet of topsoil for