2011-06-30_REVISION - M2002004 (82)

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GCC Rio Grande, Inc. — Pueblo Cement Plant and Limestone Quarry Exhibit E planting periods may be required to obtain desired vegetation cover results. For these reasons calendar dates for seeding and planting operations are not specified. Planting operations should be conducted during the indicated seasons based on site - specific needs, moisture regimes and vegetation purposes. Generally accepted and optional planting periods for the seed mixtures that can be used at the mine are provided in Table 7 Seed Mixture Planting Periods. Plantings undertaken outside of these generally accepted time periods may not be successfully completed, particularly in the winter when inclement weather can preclude seeding operations. Success of seeding undertaken during the summer months can be highly variable, depending upon the length of time between precipitation events, the amounts of precipitation received and plant available moisture contained in the soil. Summer hailstorms may also influence survival of seedlings. None - the -less, under certain circumstances some areas may require seeding immediately following disturbance or construction activities. In these situations exceptions may be made to the standard planting periods. Should planting efforts fail, reseeding will be performed during the next appropriate planting period. Seeding Methods Seed mixtures may be planted using either broadcast or drill seeding methods. Key to the success of planting operations is proper preparation of the seedbed. The seedbed will be evaluated for proper levels of fertility prior to commencement planting operations. Water harvesting features will be in place and adequate soil protection measures will be used to ensure stability of the seedbed during the anticipated seed mixture germination and establishment period. If soil crusting is present that has the potential to seriously impact seedling germination and establishment, it will be alleviated using appropriate methods. Sterile or benign extenders will be used when necessary to ensure even distribution of seed across the planting site. Soil fertility, water harvesting features and seedbed preparations will be sequenced and performed to optimize seedling establishment and development. Broadcast Seeding Seed will be broadcast into properly prepared seedbeds. Seed will be broadcast at the targeted pure live seed per square foot rate specified for the seed mixture being planted; broadcasting application rates will not be increased over drilling rates. Care will be taken to ensure that soil crusting will not prevent seed from lodging and to ensure soil -seed contact will be adequate. Broadcasting will be performed immediately following seedbed preparations. Broadcasting may be performed using hand held or vehicle mounted equipment. Broadcasting equipment will be calibrated to ensure that seed materials are properly distributed. Permanent rangeland seed mixtures will be preferentially broadcast seeded. The reclaimed lands on which they will be planted are topographically stable and temporary soil stabilization measures will be used to promote soil stability during the development of permanent rangeland vegetation communities. Broadcast seeding of rangeland mixtures will target an application density between 8 to 16 pure live seeds per square foot. Using a seed /seedling loss of 75 %, this density will result in an established seedling density of 2 to 4 plants per square foot. Seed application rates greater than 15 pure live seeds per square foot can be expected to adversely impact the expression of plant species diversity included in the rangeland seed mixture. Drill Seeding Seed mixtures will be drilled into properly prepared seedbeds. Soil fertility and amendments, water harvesting features and soil preparations will be sequenced and performed to optimize seedling Revised June 29, 2011 E -10 Exhibit E — Reclamation Plan