2011-06-30_REVISION - M2002004 (82)

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GCC Rio Grande, Inc. — Pueblo Cement Plant and Limestone Quarry Exhibit E Temporary Vegetation Cover This seed mixture will be used to establish a temporary vegetation cover on lands that have been disturbed and will be re- disturbed by ongoing mining and reclamation activities in the future. It will normally be used on lands whose interim periods between physical disturbance are projected to last more than one growing season. This seed mixture will be used to establish a quick growing, permanent vegetation cover that will serve to reduce storm water runoff, reduce water and wind erosion, and minimize habitat available for the establishment of noxious weeds. Typical uses for this seed mixture include areas around facilities, topsoil and subsoil stockpiles, and other lands requiring permanent vegetation cover. Cool - season, rhizomatous grasses will be the primary plant species in this mixture, with at least one forb species being included as a nitrifier. An example of this seed mixture is provided in Table 2 Temporary Cover Seed Mixture This seed mixture will be applied at the pure live seeds per square foot rate indicated in Table 2. The seed mixture can be planted using either drill or broadcast planting methods as described under Seeding Methods. The cool- season grasses contained in this seed mixture are adapted to growing conditions that occur during the spring and early summer, and fall. Therefore, this seed mixture will normally be planted in the late fall or early spring; summer plantings will be avoided. Cover Crop Cover cropping is one of four methods that may be used to promote soil stability during the permanent vegetation establishment process (see Mulching & Cover Crops above). Cover crops temporarily stabilize and protect the ground surface against wind and water erosion, provide organic matter and improve soil structure. A cover crop may be used while: 1) soils lie fallow and regain suitable soil moisture, or 2) permanent reclamation seed mixtures are germinating and establishing. Permanent seed mixtures may be seeded at the same time or after a cover crop. If the cover crop is allowed to grow before planting the permanent seed mixture, it may be: 1) allowed to stand, 2) plowed under, or 3) mowed to an appropriate stubble height. Triticale will be used for cover cropping at mine. Triticale is a hybrid between wheat and rye. It is ideally suited for cover cropping use because it is sterile, annual and is capable of producing significant biomass, provided adequate moisture is available during the growing season. As a cover crop Triticale will be planted at the rate of 20 pounds of pure live seed per acre. Normally, it will be planted in the late fall, although very early spring plantings may be used if warranted, and climatic and site conditions are favorable. Either broadcast or drill planting methods may be used (see Seeding Methods). Stabilization Vegetation Cover The stabilization seed mixture will be used in limited areas where the potential for water erosion is greater and ensuring soil stability is of particular concern. Special areas carrying or exposed to concentrated surface water runoff that are prone or more susceptible to erosion include, but are not limited to, diversions, ditches, drainage channels, sediment pond spillways, and culvert inlets and outlets. The stabilization seed mixture will be used to enhance soil stability in these types of features when vegetation lining is a part of water control structure design. Grass species adapted to mesic and hydric soil conditions will be included in this seed mixture. Cool- season aggressive sod forming grasses will compose the majority of species in this seed mixture. A portion of the plant species used in this mixture will be capable of withstanding short periodic inundation by surface water runoff. A typical stabilization seed mixture is provided in Table 3 Stabilization Seed Mixture Revised June 29, 2011 E -8 Exhibit E — Reclamation Plan