2011-06-30_REVISION - M2002004 (82)

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GCC Rio Grande, Inc. — Pueblo Cement Plant and Limestone Quarry Exhibit E volunteer growth of underground plant parts capable of regeneration is supported. The following topsoil /subsoil replacement plan will be utilized when the salvaged soil is being directly hauled and placed on final graded backfill: • All suitable subsoil (AC and B- horizons) will be directly hauled and placed to an average 12 -inch depth on final graded and ripped backfill prior to the placement of the A- horizon topsoil. • All topsoil (A and E- horizons) will be directly hauled and placed to an average six -inch depth on final graded and ripped B- horizon. • Records detailing topsoil and subsoil replacement depth and volumes will be maintained at the mine and compiled in the Annual Reports. Stockpiled Soil Replacement Plan. If final graded backfill is not available for direct haul topsoil and /or subsoil placement, then Rio Grande will utilize the following replacement plan: • Subsoil (AC and B- horizons) will be hauled from designated subsoil stockpiles and placed to an average 12 -inch depth on final graded and ripped backfill prior to the placement of the A- horizon topsoil. • Topsoil (A and E- horizons) will be hauled from designated topsoil stockpiles and placed to an average six -inch depth on final graded and ripped B- horizon materials. Topsoil and subsoil materials will be removed from the stockpiles when soil moisture conditions are suitable to minimize soil compaction and pumping due to high soil moisture contents. Records detailing topsoil and subsoil replacement depths and volumes will be maintained at the mine and compiled in the Annual Reports. SOIL AMENDMENTS After final topsoil placement and grading, Rio Grande will collect and analyze topsoil samples to test for soil fertility. A 500- by 500 -foot grid will be superimposed on a map of the reclaimed area. Six soil samples will be collected within each 500 by 500 -foot grid at a density of approximately one sample per acre. The six samples will be collated, mixed and sent to the laboratory for analysis for the major nutrients of nitrogen, phosphorous and potassium. The laboratory results will determine the nutrient amendments necessary for establishment of native upland prairie. If necessary, phosphorous and potassium nutrient amendments will be applied to the topsoiled areas after final grading, but prior to ripping and surface roughening operations. One equipment pass with a ripper or a disk will incorporate these nutrients to a sufficient depth. Due to the inherent fertility of properly segregated and handled topsoil, nitrogen usually will not be required. WATER HARVESTING & EROSION CONTROL MEASURES A variety of water harvesting and conservation, and erosion control methods may be used to harvest and conserve precipitation. Primary water harvesting, water conservation and erosion control methods and practices include: contour furrowing, land imprinting, mulching (straw, native hay or hydro), cover cropping, and placement of erosion control blankets. Descriptions of these methods and practices that can be used to harvest and conserve water and control soil erosion are described below. Revised June 29, 2011 E -4 Exhibit E — Reclamation Plan