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6.4.3 EXHIBIT C -Pre-minine and Minine Plan Map(s) of Affected Lands The maps are well done and clearly illustrate the pre-mining and mining plan for this area. 6.4.4 EXHIBIT D -Mining Plan The overall mining plan appeazs to be straightforwazd with respect to extraction; however, the processing portion of the plan is unclear, particulazly with respect to the volume of waste material that will be generated. The narrative indicates that an on-site power screen will be used to process the first phase reject and then additional processing will occur at the main plant in Colorado Springs to further refine the sand and obtain the final product. The reject will then be trucked back to the pit to be used as backfill during the reclamation phase. In order to properly evaluate the reclamation liability and determine the appropriate financial warranty, a close approximation of the volumes of material involved is necessary. Please provide an estimate of the percent of reject that can be expected from this deposit. It was mentioned in the introduction that material would be imported since the plant reject will be returned to the mining site, however, since it was generated from that site "technically" it is not being imported. Since the operator has other mines from which material is processed at their main plant, how will the material processed from this site be kept sepazate from other sites? If there is not a clear procedure for this the applicant may want to consider addressing the requirements of Rule 3.1.5(9), which allows for the importation of off-site material as long as it is inert. The mining plan calls for salvaging 6 inches of topsoil, but the reclamation plan calls for replacement of 4 inches. Why is there a discrepancy? Also, although the soil survey describes the various profiles as having a surface layer of 4-6 inches, the effective rooting depth is 60 inches. Also, the immediately underlying layer of soil is usually described as being brownish sand about 6 inches in depth for two of the soils and a sandy loam 24 inches thick for the other soil. In other words, the available "topsoil" is not necessarily the single surface horizon. It appears that the top foot of this sandy soil is higher in organic matter and likely facilitates the active exchange of nutrients for this plant community as well as providing for better water holding capacity. Our experience is that more topsoil salvaged and replaced leads to more successful reclamation. It would appear that in this situation 6-12 inches of topsoil should be salvaged with a minimum replacement of 6 inches. This would allow the equipment operators to utilize color change as an indicator while stripping is occurring. In addition, replacing a thicker layer of the most suitable growth medium will provide for a better chance of successful revegetation establishment. Please clarify the stripping and replacement depths for the topsoil.