2009-12-11_REVISION - M1977036 (13)

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EXHIBIT L Reclamation Costs The attached spreadsheet represents the estimated cost for the Division to reclaim approximately 290 acres of disturbance at the Greeley 35 Avenue Mine site. The 290 acres were calculated by removing the 55.5 acre Industrial Use Area from the 345.5 acres of total disturbance. Lafarge intends to continue using their plant site improvements within the Industrial Use Area after the 35 Avenue Mine site is mined; therefore, this portion of the property would not require reclamation. During the mining of the Lafarge Brown portion of the West Pit, the West Pit will not be completely reclaimed and final reclamation will not be completed for the South Central Pit, and East Pit. In addition, it is possible that the North Central Pit, which is currently reclaimed as an open water pond, may need to have some adjustments made to the slopes that are currently underwater. A bathymetric survey will be completed to determine whether or not this is needed; however, for purposes of our estimate we have assumed that some minor earthwork will be needed to adjust the underwater slopes. Out of the 290 acres of disturbed area, for our estimate, we made the following assumptions: • approximately 7 acres of land north of the North Central and East Pits have already been reclaimed above the water surface with slopes that range between 3:1 and 5:1 (these areas have been top soiled and revegetated as well); • the 60.5 acre area shown on our reclamation plan as the area to be reclaimed as "upland or wetland" will only be raised to an elevation to reclaim the land as a wetland; • there will be 83.5 acres of land that will need to be filled and reclaimed as upland; and • there will be approximately 139 acres of open water pond. In order to calculate the amount of reclamation fill that will be required to reclaim the property, we assumed the following: • 481,000 cubic yards of fill for the West Pit and South Pit (this number was based on proposed mining and reclamation topography); • 760,000 cubic yards of fill to raise the area in the East Pit that is underwater to a wetland elevation (we estimated the pond would need about 15' of fill on average); • 25,000 cubic yards of fill to raise the area in the Northeast corner of the South Central Pit that is underwater to a wetland elevation (we estimated the area would need about 5' of fill on average); • 14,000 cubic yards of fill to adjust the submerged slopes of the North Central Pit open water pond. In order to calculate the amount of topsoil that will need to be imported, we started with the fact that 83.5 acres will require topsoil in order to reclaim the land as upland. Assuming 6" of topsoil over this acreage, 67,357 cubic yards of topsoil are needed. The site currently has 36,000 cubic yards of topsoil available (the topsoil on the Lafarge Brown property and the topsoil in the berm along North 35 Avenue north of the site entrance). Therefore there is a deficit of 31,357 cubic yards of topsoil. Greeley 35`" Avenue Mine (M -1977 -036) DRMS 112 Reclamation Permit Amendment Application Page LI ofLI