2011-06-30_REVISION - M2002004 (82)

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GCC Rio Grande, Inc. — Pueblo Cement Plant and Limestone Quarry Exhibit E Surface Roughening Surface roughening is the most important water harvesting and retention method that can be used in reclaiming disturbed lands. Surface roughening that can be used at the mine includes contour furrowing, contour drill seeding, cleat tracking and soil gouging. Surface roughening activities will be performed on the contour whenever physically and operationally feasible. Construction along the contour is particularly critical for surface roughening with a linear configuration. Surface roughening operations will be timed appropriately during the soil reconstruction and vegetation planting process to optimize its effectiveness while supporting vegetation establishment. Contour Furrowing Contour furrowing will be established using a plow, disc or gang ripper. The furrows will be constructed approximately on the contour. Typically, furrows will be placed 2 to 4 feet apart from one another. Contour furrow length will not exceed 100 feet. Shorter lengths may be used on steeper slopes (i.e., greater than 5h:lv). A gap or earthen plug in the furrow will be created periodically by lifting the furrowing implement for a distance of several feet and then setting it in the ground again. Furrow depth will depend upon soil moisture conditions and texture; a plowing, discing or ripping depth of 6 inches will be preferred. A plow or disc will normally be used on lower slope areas; a gang ripper may be needed on steeper slopes. Contour furrowing will be constructed prior to or concurrent with seeding operations, being dependent upon equipment use and capability. Land Imprinting A land imprinter will be pulled behind a tractor or bulldozer of suitable size and configuration. Land imprinting typically creates small pyramid- shaped depressions in the soil surface. The land imprinter is omni - directional in terms of use and may be pulled over the reclamation area in any direction, but operations will be conducted along the contour when this is physically possible. Care will be taken to evaluate soil moisture, which should be adequate to hold depression shapes, but not so wet as to cause damage to soil structure. Land imprinting will normally be performed after seeding and mulching (when applied) have been completed. Cleat Tracking Cleat tracking can be used to establish surface roughness when soil moisture is adequate and heavy equipment access is limited by slope steepness to travel parallel with the slope. A bulldozer or other heavy tracked equipment is walked up and down the slope to create small soil depressions with its tracks cleats. Soil Gouging Soil gouging is accomplished by creating small depressions in the reclaimed surface. These depressions collect surface water runoff and provide soil zones with soil moisture contents that are elevated over soils in the interstitial areas between them. These depressions can provide suitable habitat for establishment of woody and other plant species that require higher . soil moistures. Soil gouging may be performed in those portions of the mine where establishment of woody plants is a permanent reclaimed vegetation community goal. Gouging may be established using a Hodder gouger, bulldozer, motorgrader or other suitable equipment. Revised June 29, 2011 E -5 Exhibit E — Reclamation Plan