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Aggregate Industries, Morrison Quarry Amendment No. 7 to Permit M-1973-021 Morrison, CO October 2021 | 39 Costs for QA/QC testing assume a daily unit rate for reclamation of mined areas of the North and South Quarries. For purposes of cost estimating it is assumed up to 120 days will be needed. Item 9.0 Un-mined Areas Earthwork Areas disturbed within the Morrison Quarry, but outside of mining boundaries, will be reclaimed to blend with surrounding topography. This earthwork includes rough grading of approximately 50.82 acres. Areas to be reclaimed include haul roads, processing areas, and structure foundations. For areas where steeper slopes will remain, up to 0.33 acre of geosynthetic slope stabilization will be installed. Item 10.0 Soil Conditioning All reclamation areas within the Morrison Quarry will be reclaimed in a manner that allows for proposed post-mining land use. Reclamation areas will be backfilled as described in Items 8.0 and 9.0, then covered with a layer of growth medium material. The growth medium material will be developed from a blend of any available topsoil stockpiled on site as well as material available from the excavation and breakdown of the fine-grained sedimentary overburden rock, supplemented as needed by imported topsoil, biosolids, or compost and then blended, scarified, seeded, and mulched. The topsoil materials will be transported using front-end wheel loaders or articulating haul trucks. This material will then be uniformly spread in 6-inch layers and mixed with conventional earthmoving equipment, such as bulldozer rippers or the teeth of an excavator bucket, into the top 12 inches of the subsoil. For reclamation of the mined and un-mined areas, it is anticipated that the soil conditioning area covers approximately 155.4 acres. For purposes of estimating costs (Exhibit L – Reclamation Costs), Aggregate Industries, Inc. estimates that up to 25% of the required topsoil sources will be collected and stockpiled on site, providing an assumed 31,339 cubic yards of topsoil. To provide 6 inches of topsoil cover for the remaining 75% of reclamation areas, Aggregate Industries, Inc. estimates importing 94,017 cubic yards of organic material to meet the requirements below. The costs of utilizing topsoil sources on site versus imported soil growth medium have been broken out as separate lines in the estimated costs table in Exhibit L – Reclamation Costs. To reduce the dependency on imported topsoil, the operator will continue to evaluate amending site soils to develop suitable organic material prior to full reclamation of the site. Imported soil amendments will be from a local source of material to be generated during reclamation. Caked or lumpy soil amendments will not be accepted. If selected as the preferred source, manure will be dry cow, horse, or sheep manure that has been stockpiled for a minimum of 1 year. Manure will not be so caked or lumpy that it cannot be spread uniformly. Compost manure will be stabilized through at least one heating cycle (120 to 140 degrees Fahrenheit), turned at least once, windrowed for at least 45 days, and stockpiled for a least 2 months. Biosolids or compost biosolids, containing municipal biosolids, will meet Colorado Department of Public Health and Environment (CDPHE) Water Quality Control Commission 5 Code of Colorado Regulations 1002-64 Biosolids Regulation No. 64, including permitting and