2003-03-31_REVISION - M1977344 (2)

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The pre-mined land has a relatively low grazing value due to the poor soil conditions, dry climate, and the generally steep terrain. The pre-mining topography depicted in the C-2 Mining Plan Map is that of an erosional, arid landscape. As indicated by Exhibit F, Figure F-1 Reclamation Plan, post- mining regrading of the formerly rocky and inaccessible steep cliff areas will result in a final topography more suitable for grazing, In addition, the planting of native grasses should improve the available forage for grazing. Materials Handling As discussed in the Mining Plan, Exhibit D, the mining cuts will be backfilled with overburden material as shipping and mining of subsequent cuts proceeds. The overburden material will be removed from the new mining cuts using a Liebherr 994 hydraulic shovel and Caterpillar 992G (or D) front-end loaders, and loaded into Caterpillar 785D haul trucks. The haul trucks will then transport the material directly to a previously mined cut, and the overburden material will be initially dumped and left at the natural angle of respose, which is approximately 1.3:1 (H:V). As the back811ing operations continue, the backfilled zone will progress across the previously mined cut. When necessary, the backfilled material will be regraded/shaped to achieve slopes no steeper than 3:1, as indicated on Figure F-1, Reclamation Plan Map. The haul truck activity (each weighs more than 100 tons empty} will crush the shaley overburden material, creating a layer of fine-grained material on the surface. The heavy truck traffic will also help compact and expedite the settlement of the backfill material. The upper surface of the backfill area will be rough-graded using a Caterpillar 16H grader. Care will continue to be taken to continually grade the temporary haul roads to minimize the wear-and-teaz on the mining equipment and for safety reasons. As settlement of the backfill occurs, the final surface will be regraded to prevent ponding of storm water on the surface. The majority of the affected area will be graded to approximately 1-2% slopes to allow runoff while minimizing erosion (see Figure F-1, Reclamation Plan Map). Water Resources The mining of the Bear Creek watershed south of state Highway 50 will impact the current hydrologic conditions in the lower reaches of Bear Creek. Through at least 2002 and continuing to the present, regional drought conditions have eliminated the flow of surface water in the upper portion of Bear Creek down to and somewhat below the double concrete box culvert under Highway 50. in the lower section of the creek further downstream of the culvert, however, Beaz Creek becomes a gaining stream. In October 2002, a site inspection indicated no flow was observed at the culvert under Highway 50, while a flow of less than 0.5 CFS was observed at the Highway 120 crossing neaz the mouth of Bear Creek as it approaches the Arkansas River. Prior to the onset of drought conditions in 2001, Holcim had originally planned to establish wetlands along the planned realignment of Bear Creek, which was originally to be diverted to the west- southwest around the area to be mined. This was the original basis for the initia1404 Permit with the U.S. Army Corps of Engineers. With the elimination of flow in upper Bear Creek, however, it was concluded that this wetlands mitigation plan was no longer viable, and the 404 Permit with the Corps of Engineers was modified in late 2002 to rely upon the establishment of supplemental wetlands at the Transit aggregate operation located at the mouth of Hardscrabble Creek along the Arkansas River. Exhibit E - revised.doc Page 2 of 5