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Lyons Quarry ��� <br /> 112d Reclamation Permit Operations <br /> Technical Revision <br /> The surface elevation across the site ranges from elevation (El.) 5,508 feet near the entrance of the <br /> site to above El. 6,000 feet at the south end of the site. Existing natural slopes in sedimentary rock <br /> strata are as steep as 1.75 horizontal to 1.0 vertical (1.751-1:1.0V), where the sedimentary strata are <br /> capped by the Lyons Sandstone. Where the sedimentary rocks are not capped by the Lyons <br /> Sandstone, these slopes ranged from 2.01-1:1.OV to 4.01-1:1.OV. <br /> The flattest measured slopes were in areas mapped as landslides. Existing natural slopes in the <br /> dacite are nearly vertical where the dacite is exposed along the north side of South St. Vrain Creek. <br /> Where the dacite outcrops in the drainage along the west side of the site, the existing natural slopes <br /> range from 0.31-1:1.OV to 2.21-1:1.OV. This large range in the natural slope was measured along west <br /> facing slopes over a span of approximately 300 feet. <br /> Vegetation is generally absent in the leveled and mined areas. Vegetation over the remainder of the <br /> site is described by previous investigators as grasses, forbs, and shrubs/brush with various <br /> cottonwoods, willows, Virginia creeper and golden current found along the drainages. <br /> Surface water is present along the north edge of the site, in South St. Vrain Creek. Groundwater is <br /> present, ponded in low areas and observed as wet areas along the base of the highwall. <br /> Groundwater is also anticipated perched above siltstone and shale layers in the Fountain Formation. <br /> Exhibit E — Reclamation Plan <br /> The post mining use remains unchanged with the land being reclaimed to cattle range and pasture <br /> land in the production, stockpile, and pit floor areas. This Technical Revision shows two areas of <br /> reclamation. The first reclamation area, described in this document, addresses areas affected by <br /> the pit and highwall. The second reclamation area, to be described in a future Technical Revision <br /> developed in coordination with Boulder County, addresses areas affected by the production and <br /> stockpile areas within the meadow area that was significantly impacted by the September 2013 <br /> flooding. <br /> The following paragraphs provide a summary of the proposed reclamation for Lyons Quarry <br /> Reclamation Area 1, a total area of 40.8 acres. The Site Grading Plan, Attachment B, shows the <br /> proposed cut and fill slopes and final grading. Exhibit F — Reclamation Plan Map, Attachment C, <br /> shows the two planned reclamation areas and the types of reclamation proposed in Reclamation <br /> Area 1, based on a slope analysis of the final grading. Section 5.1 provides more detail of the <br /> proposed Reclamation Plan and Scope of Work developed for estimating the costs for Exhibit L— <br /> Reclamation Cost, Attachment D. Table 1 shows the proposed reclamation schedule with planned <br /> reclamation phases, sequence, and estimated durations for each phase. <br /> Table 1 — Reclamation Schedule <br /> Final Design and Construction Documents 6 months <br /> Procurement of Construction Contractor 2 months <br /> Procurement of Growth Medium Sources 2 months <br /> Mobilization, Site Prep. and Initial Earthwork Construction 1st season <br /> Soils Analysis and Test Plots for Revegetation Plan 1st season <br /> Mobilization and Final Earthwork Construction 2nd season <br /> Revegetation, Sediment Pond Reclamation, Demobilization 2nd season <br /> November 2016 3 <br />