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6. Dozer Blade Comments noted. Since the reclamation involves the dozing of previously moved materials and not geologically consolidated materials less effort is needed to cut into the material. if this were construction using undisturbed earth DMG's assumptions would be correct. A D9 is quite capable of making the initial cuts into a compacted road surface with a "U" blade. Subsequent pushes of this compacted surface would take much less effort when taken from the side of the cut using normal dozing practices. Due to the lack of consolidation the fill should be considered "easily dozed" materials. Furthermore, the Caterpillar Performance Handbook specifically recommends the "U" blade for land reclamation purposes. Dozing Method Comments noted. However, this must be recognized as another layer of conservatism built into the cost estimates. 8. Material Consistency DMG maintains that the material to be dozed should carry a "material consistency" of 0.9 representing the difficulty of dozing between a consolidated stockpile and hard to cut; frozen material. The Caterpillar Performance Handbook production numbers uses the following scenario as a basis for its numbers: "Machine cuts for 15 m (50 feet), then drifts blade load to dump over a high wall." It has been our observation that the scenario for the cut and drift of materials at the Deserado Mine is consistent with this description. The only exception is with the initial cut into the hazd packed surface. Once this initial crust is breached the dozing becomes much more routine and subsequent cuts easily peal this crust with the side of the blade in a manner best described as one-sided slot dozing. Our most recent and most definitive observations came from the reclamation performed at the East Portal last fall. Dozer blades were filled in less than 50', typically less than 30', and material drifted normally. Based on these observations it is our assessment that a correction factor of 1.00 is appropriate for material consistency. 9. Equipment Operator Time In the CIRCES program it is assumed that an operator is somehow `married' to a single piece of equipment and no allowance is made for the ability of that operator to operate two pieces of equipment even when the sum of two pieces of equipment utilization is only 50%. DMG uses the analogy that the water truck will be needed for other tasks such that it will be needed full time. The only other potential use that we can see that DMG is alluding to for adding moisture to fill for compaction purposes. As discussed earlier, such application is neither necessary nor required in the permit. It would only serve to lessen the water holding and infiltration capacity of the reclaimed site resulting in increased runoff and higher bulk density of the soil causing less favorable plant growth. January 15, 2003 6 Permit Revision #4 Comments Blue Mountain Energy, Inc.