2012-08-14_REVISION - M2002020 (5)

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Mr. Peter Hays RE: City of Greeley M- 2002 -020 August 10, 2012 9. The Lafarge Parcel No. 80536100015 is associated with an expired local permit and not associated with a real property, easement, or right -of -way. 10. The list of property owners and parcel numbers on revised Exhibit C -1 attached has been updated to include Double SM Farms (Parcel No. 80536000027). The Double SM Farms property owner is the same as property owner Flatiron Companies. 6.4.4 Exhibit D — Mining Plan 11. All creeks, roads, oil and gas wells and lines, power and communication lines, and easement owners are included on the revised Exhibit C -1 and Exhibit C -5 attached. 12. A minimum width of 50 feet is needed between any constraining feature (i.e. permit boundary) and the final reservoir top of bank to allow room for installation of the slurry wall. The railroad tracks to the south of the proposed mining cell and 35 Avenue to the west create space constraints between the permit boundary and the existing lake(s) top of bank. Therefore, around the south and west sides of the proposed mining cell, crest width may need to be added for installation of the slurry wall. Crest width will be added by placing stable fill material on the existing lake(s) side slopes until the mining cell top of bank is extended far enough to provide a minimum crest width of 50 feet. The fill material will be placed from the top of bank to the existing lake(s) bottom (estimated to be approximately 20 feet), maintaining a 3H:1V slope. This will not only extend the top of bank further into the mine cell, but will also extend the toe of the slope. Based on the new crest width and associated toe of slope location, mining will proceed at 3H:1V from the new toe of slope to bedrock. This process is depicted in the cross - section on the revised Exhibit C -5 attached. 13. Typical dewatering trenches and settling basin/discharge locations have been identified on the revised Exhibit C -5 attached. Depending upon the size of the mining cell, groundwater inflow, and area of disturbance, the settling basin(s) will be sized to provide enough detention so that the discharge will not exceed Colorado Discharge Permitting System standards. 14. If topsoil or overburden stockpiles are inactive for 180 days or more, they will be seeded with a fast growing grass seed mixture. 15. The applicant has committed to mining at 3H:1V slopes and acknowledges that mining at slopes steeper than 3H:1V will be considered a serious violation of the permit. 16. If mining excavation occurs within 50 feet of the permit boundary or a man-made structure, an agreement will be obtained from the property owner or a stability analysis will be performed. The proposed offset distances are shown on the revised Exhibit C -5 attached. Page 2 of 5