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i <br /> Lyons Quarry <br /> 112d Reclamation Permit Operations ��� <br /> Technical Revision <br /> capped by the Lyons Sandstone. Where the sedimentary rocks are not capped by the Lyons <br /> Sandstone, these slopes ranged from 2.OH:1.OV to 4.OH: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 feat. <br /> Vegetation is generally absent in the leveled and mined areas. Vegetation over the remainder of the <br /> site is described by previous scientists 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 /> 3 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 addresses areas <br /> affected by the pit and highwall. A second reclamation area, to be described in a future Technical <br /> Revision developed in coordination with Boulder County, will address areas affected by the <br /> production and stockpile areas within the meadow area that was significantly impacted by the <br /> September 2013 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. Ex ibit F— Reclamation Plan Map, Attachment C, <br /> shows the two planned reclamation areas and theitypes of reclamation proposed in Reclamation <br /> Area 1, based on a slope analysis of the final gracing. Section 5.1 provides more detail of the <br /> proposed Reclamation Plan and Scope of Work d veloped for estimating the costs for Exhibit L— <br /> Reclamation Cost, Attachment D. Rule 6.5-Geotecchnical Stability Exhibit, Attachment E, provides <br /> the basis for the Site Grading Plan. The GeotechOical Stability Exhibit limitations include a 3 year <br /> limit on the use of the report due to possible changes over time in land use, site conditions, <br /> regulations, or other factors. This reclamation pla is based on the premise that the conditions <br /> described in the geotechnical report for the analyses performed and the conclusions and <br /> recommendations presented still exist at the site and should remain valid for the duration of the <br /> planned reclamation. A Grading Plan Verification Letter, signed and sealed by a registered <br /> professional engineer, Attachment F, is a letter verifying that the slopes and configurations shown on <br /> the Grading Plan meet the specifications of the Geotechnical Stability Exhibit. <br /> Table 1 shows the proposed reclamation schedule with planned reclamation phases, sequence, and <br /> estimated durations for each phase. <br /> February 2017 1 3 <br />