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Pikeview Quarry Environmental Assessment Page 27 <br />boundary with National Forest System lands and resulted in very steep slopes with gradients <br />varying from 1.5:1 to 1:1. Some of these steep slopes have been reclaimed through <br />' benching and revegetation. Other parts remain too steep to be reclaimed and too unstable to <br />allow further mining in the areas below. Three representative cross-sections of the Pikeview <br />Quarry are presented in Appendix C. These cross-sections include both National Forest <br />System land and private land. The location of limestone, shale/mud, sandstone and granite <br />is indicated in each cross-section. <br /> Soils within the proposed project azea are derived from decomposed Pikes Peak <br /> Granite parent material. The parent rock is deeply weathered granite, composed of quartz <br /> and orthoclase, with biotite being an accessory mineral. The granite is composed of large <br /> crystals that are released as the biotite weathers. These large crystals then form a mass of <br /> coarse-grained material with little clay to serve as binding material and as exchange medium <br /> for soil nutrients. The complex thus formed is highly erosive under concentrated water <br /> flows and may be relatively unproductive due to a lack of soil nutrients. Soils developed <br /> from Pikes Peak Granite are pinkish in color due to the feldspars contained in the parent <br /> material (Hydrosphere, 1999). <br />' The soils in the azea of the proposed project site and surrounding areas aze described <br /> as Tecolote-Pendant (USDA, Soil Survey, 1992): deep and shallow, well drained and <br /> somewhat excessively drained soils that formed in material weathered from limestone and in <br /> cobbly or stony colluvium over weathered granite. This general soil classification is used to <br /> describe areas with similaz natural landscape. <br /> According to the detailed soil classification, which describes individual soil types, the <br /> area occupied by the proposed project on National Forest System land consists of Sphinx- <br /> Rock outcrop complex. These soils aze associated with mountainsides and upland ridges <br />' (15-80% slopes). They are somewhat excessively drained, shallow Sphinx soils formed <br /> from Pikes Peak granite, and they have rapid permeability, very low available water <br /> capacity, rapid runoff, and severe hazard of water erosion. <br /> Typically, about 40 to 65 percent of the surface of the Sphinx soil is covered with <br /> vegetation and forest litter. The surface layer is brown gravelly coazse sandy loam about 4 <br />' inches thick. The next layer is yellowish brown very gravelly loam coarse sand about 8 <br /> inches thick. Highly weathered, coazse-grained granite, or gnu, is below a depth of about <br /> 12 inches. <br /> About 5 percent of this unit is included in areas of Garber very gravelly coarse sandy <br /> loam on mountainsides, commonly adjacent to drainage ways; and 10 percent is soils that <br /> have a surface layer that is darker than that of the Sphinx soil. <br />' The soils in the area currently occupied by the Pikeview Quarry (on private property to <br />the east of the National Forest System land), consisted of Tecolote very gravelly sandy loam <br /> and very stony, and were removed during mining operations in the late SOs and early 60s. <br /> These soils aze associated with mountainsides on slopes of 15-40% slopes. They are <br /> well drained, deep soil formed in cobbly or stony colluvium over weathered granitic rock, <br />' <br /> Hydrosphcrc Rcsourcc Consullanls, 1002 Walnu[ Street Sui[e 200, Boulder, CO 80302 <br /> <br />