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Lyons Quarry ��� <br /> 112d Reclamation Permit Operations <br /> Technical Revision <br /> Fill materials will consist of overburden materials that are uniformly graded continuously from <br /> boulder size to silt size, with a maximum particle si a 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 1 OH:1 V. The bench width will be adjusted to achieve an overall 150-foot-high slope with a <br /> stability 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 the maximum particle size <br /> of the fill materials <br /> • Compacted to achieve greater than 90% of the maximum dry density in accordance with <br /> ASTM D698 <br /> • Placed in a manner that allows for a moisture content within 3% of optimum based on ASTM <br /> D698 <br /> Final Grading of all fill slopes, benches, crest areas, and toe areas will ensure that water is not <br /> allowed to pond on or adjacent to the fill slopes. <br /> Item 6.0—Fill Slope Scour Protection <br /> The toe areas of fill slopes that extend into the low-lying areas and the flood way of South St. Wain <br /> Creek will be protected from scour by future flood events by the construction of a riprap scour berm <br /> as shown in Section B of the Site Grading Plan, Attachment A. The scour protection is designed to <br /> withstand a minimum 100 year flood event. The riprap gradation for the scour berm has a D50 of 28 <br /> inches and a maximum stone size of 42 inches. <br /> Item 7.0—Reclamation Areas and Soil Conditioning <br /> Reclamation areas have been differentiated by a site slope analysis as shown on Exhibit F- <br /> Reclamation Plan Map, Attachment C. Areas of 1.5H:1 V slopes will be too steep to effectively apply <br /> soil amendments and produce a vegetative cover; therefore the slope will be covered with a 2-foot <br /> thick layer of talus riprap (D50 = 12 to 14 inches) and compacted using an excavator bucket. <br /> Approximately 4.8 acres will require talus riprap coverage. We anticipate that sufficient talus riprap <br /> can be generated from the massive sandstones onSite and will be selectively blasted and screened <br /> as needed to produce specified grading. <br /> Areas with slopes flatter than 1.51­1:1V will be reclaimed in a manner that allows for livestock grazing <br /> and movement along the slope face. These areas Will be backfilled as described above then covered <br /> with a layer of growth medium material (e.g. topsoil, biosolids, compost). The growth medium <br /> material will be developed from a blend of any available topsoil stockpiled on site and material <br /> available from the excavation and breakdown of the fine grained sedimentary overburden rock, <br /> supplemented as needed by imported topsoil, biosolids, or compost, then blended, scarified, seeded <br /> and mulched. This material will then be uniformly mixed, via rippers or the teeth of an excavator <br /> bucket, in to the top 6 to 12 inches of the on-site subsoil. It is anticipated that the area to receive <br /> amendments covers approximately 39 acres. <br /> Item 8.0—Sedimentation Pond Reclamation <br /> The sedimentation pond will be backfilled at the end of reclamation to blend with the surrounding <br /> topography, unless post-mining use dictates otherwise. Backfill requirements will be the same as <br /> those stated in Item 5.0. The pond will be backfilled using approximately 2,200 cubic yards of <br /> February 2017 17 <br />