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difference between the two (Table 2.2). There may be local visible <br />• changes to the existing topography in comparison to the approved <br />topography; however, objective measurements and geomorphic analyses <br />indicate the similarity of approved and existing topography. Minor <br />fluctuations in reclaimed topography (specifically slope) are <br />accommodated for in Colorado state regulation 4.14.2(1) as follows: <br />Postmining final graded slopes need not be uniform but <br />shall approximate the general nature of the premining <br />topography... <br />The Swale at the top of the mine is certainly a visible feature when <br />viewed from the top of areas 9/10, 7, or 31. However, it appears to <br />have no major impact on measures of drainage basin shape or form such as <br />hills lope gradient or hypsometric curves. The latter indicate that <br />material has not been significantly relocated within the mine area. A <br />• valid concern may be the stability of oversteepened (relative to <br />approved hillslopes) portions of the swale area and compatibility of the <br />surface with surrounding landforms. Comparison of upper Swale slopes <br />with natural colluvial slopes indicates that the Swale slopes do not <br />exceed the gradient of natural slopes composed of similar materials. <br />The colluvial slopes have a good vegetative cover with little or no <br />evidence of rilling at gradients often exceeding swale-area gradients. <br />In regard to landform compatibility it was shown that a swale area <br />similar to that on the mine can be found on the dip slope to the north <br />of the mine. <br />In general, stream channels of the existing topography have similar <br />erosive power as channels on the approved topography. In addition, <br /> <br />25 <br />