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Lyons Quarry ��� <br /> 112d Reclamation Permit Operations <br /> Technical Revision <br /> Item 3.0— Erosion, Sedimentation, and Dust Control Plan <br /> This item covers the design, installation, maintenance, and removal of temporary erosion, <br /> sedimentation, and dust control features. These features will include just over two-thousand linear <br /> feet (2000 LF) of sediment control berm along the bottom perimeter of the project site and <br /> approximately three thousand five-hundred linear feet (3800 LF) of an upland diversion berm/ditch <br /> above and around the quarry disturbed areas, as shown on Section B and Section C of the Site <br /> Grading Plan, Attachment B. <br /> The contractor will be required to install these sediment control features prior to any ground <br /> disturbing activities and maintain them throughout the duration of the project. Upon completion of the <br /> project, the bottom perimeter sediment control berm will be incorporated in the Scour Berm at the <br /> base of the fill slopes. The installed temporary erosion and sediment control features assume BMP's <br /> in accordance with Boulder County Storm Drainage Criteria Manual, including but not limited to <br /> Temporary Diversion Channels, Earth Dikes and Drainage Swales, and Sediment Control Logs. <br /> The sediment control berm and upland diversion berm/ditch footprints will be cleared and grubbed. <br /> The upland diversion berm/ditch will be cut and filled using overburden soils and supplemented with <br /> materials from other excavation areas. Some drill and blast excavation may be required. The <br /> sediment control berms will incorporate geotextile installed according to the manufacturer's <br /> guidelines. <br /> Dust generated from the project area during work and off-work periods will be controlled and kept to <br /> a minimum. The contractor will be required to develop and implement a Dust Control Plan, including <br /> Wind Erosion/Dust Control BMP's and application of water to working areas during working and non- <br /> working periods, including weekends, throughout the duration of the project. <br /> Item 4.0— Debris Removal <br /> This item includes removal of debris collected from across the site following the recent flooding. The <br /> debris was gathered and stockpiled at the site out of the drainage way. It is assumed that 25 loads <br /> of debris material will be hauled from the site. <br /> Item 5.0— Earthwork Excavation, Fill, and Compaction <br /> Once the site controls are installed, the grading plan will be implemented. All areas will be cleared <br /> and grubbed prior to excavation and backfilling. As described in the Geotechnical Stability Exhibit, <br /> Attachment E, cut slopes in the overburden sedimentary rock will be excavated using drill and blast <br /> methods to achieve overall 1.5H:1 V slopes. Fill slopes in the pit highwall area will be placed and <br /> compacted to achieve 50-foot-high benches, sloped 2H:1 V, with 15 foot wide bench widths. The <br /> anticipated cut/fill quantities to establish the final grading are approximately balanced at 364,700 CY. <br /> Fill materials will consist of overburden materials that are uniformly graded continuously from <br /> boulder size to silt size, with a maximum particle size equal to one-half to two-thirds of the lift <br /> thickness and maximum 45 percent fines in the minus 3-inch fraction. Benches will be constructed <br /> 15-foot-wide at 50-foot contour intervals and will be sloped from west to east at grades not steeper <br /> than 10:1. The bench width will be adjusted to achieve an overall 150-foot-high slope with a stability <br /> factor of safety greater than 1.5. All fill will be placed as follows: <br /> • Placed in horizontal lifts not to exceed 2 to 3 feet thick, based on gradation of fill materials <br /> • Compacted to achieve greater than 90% of the maximum dry density in accordance with <br /> ASTM D698 <br /> November 2016 1 6 <br />