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GCC Rio Grande, Inc. — Pueblo Cement Plant and Limestone Quarry Exhibit E <br />vegetation and turf reinforcement mat for higher slopes. Specifications for the reconstructed arroyos are <br />in Appendix F "Surface Water Management Plan." This approach will provide an erosion resistant <br />channel not exceeding existing conditions and providing adequate protection until vegetation is <br />established. <br />Because the reclaimed mining surface will be lower than natural topography at the highwalls, additional <br />protection measures are required. These measures include a rock - lined, sloping drop structure, which can <br />convey the 100 -year flood down the steeper slopes (4H:1 V). The drop structure, limited to a drop height <br />of 10 feet, can be formed into exposed rock or created using mined rock. The structure is "V- shaped" to <br />concentrate flows in the center and includes a scour basin, energy dissipator, which transitions the flow to <br />the reconstructed arroyo. This approach will allow existing arroyos to be transitioned into the <br />reconstructed drainage at the upper end of the mined area. <br />When establishing the final reclamation surface, consideration was given to the existing arroyo watershed <br />boundaries. The final reclamation surface includes a small "ridge" to allow surface runoff to flow towards <br />the restored arroyos, resulting in approximately the same watershed area. This approach will provide <br />reasonable assurances that peak flows and runoff volumes will not be increase over existing conditions. In <br />addition, since the final reclamation surface is flatter than existing topography, runoff peaks and sediment <br />loads will likely be less than existing conditions. <br />Additional information is provided in Exhibit D — Mining Plan and Appendix F "Surface Water <br />Management Plan." <br />TOPSOIL & SUBSOIL RECONSTRUCTION <br />Topsoil and subsoil reconstruction activities will be scheduled to allow completion of soil amendment, <br />surface manipulation activities and revegetation activities when ground conditions are favorable to <br />minimize adverse impacts to soil resources and during the appropriate season to optimize seedling <br />establishment. Topsoil and subsoil replacement operations may be conducted with a variety of suitable <br />equipment (i.e., scraper, truck/shovel, truck/loader, backhoe, dozer, etc.). Mobile equipment will be used <br />to replace topsoil and subsoil materials that will be either direct - hauled from on -going salvage operations <br />or removed from topsoil stockpiles. Each year the mined out area will be reclaimed by placing the <br />overburden material from the adjacent panel on the floor of the pit and then reapplying the subsoil and <br />topsoil, with the exception of active roadways along which the conveyor belt will be extended. <br />Suitable topsoil and subsoil available for replacement over the leveled backfill will result in an average <br />replacement depth of six inches of topsoil and 12 inches of subsoil. Varying topsoil depth and quality in <br />association with topographic features will help minimize erosion and deposition processes, optimize soil <br />resource productivity and aid in development of vegetation communities. Topsoil and subsoil thicknesses <br />may be increased on stable land forms (i.e., flatter areas) to foster increased vegetation productivity. <br />Decreased topsoil and subsoil depths may be constructed on slopes and other land forms where sil erosion <br />potentials are higher. Preferably, soil reconstruction materials with higher rock content would be placed <br />on steeper slopes to protect them against excessive erosion and promote the growth of woody species. <br />Different topsoil/subsoil depths associated with topographic position will encourage plant species <br />diversity based upon changes in slope, aspect and available soil moisture. <br />Direct Haul Topsoil Placement. Rio Grande plans to direct -haul salvaged topsoil and subsoil materials <br />to final graded and ripped backfill whenever possible. Direct - haulage of topsoil and subsoil will optimize <br />the transfer of nutrients, organic matter, microbial populations, and residual native seed bank. When <br />direct - haulage of topsoil and subsoil is performed outside of the active growing season, increased <br />Revised June 29, 2011 <br />E -3 <br />Exhibit E — Reclamation Plan <br />