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Comments and Response To CDMG Letter Dated March 15, 2002 Comment: The Division recognizes the advances made from the earlier drafts of proposed postmining topoyraphy associated with Sections 4, 9, and the northwestern quarter of Section 16. However, these areas appear to retain aspects still short of compliance with the rules. Areas proposed at elevations below approximate original contour (such as the proposed West Pit Ditch and the proposed topography of the NE'/. of Section 9) preclude, by definition, permanent excess spoil fills at elevations above approximate original contour (such as the upper reaches of the West Pit Fill). Please address the followiny gems in a refined version of the proposed postmining topography in these areas. Resaonse: Discussions with Byron Walker on the above term of "approximate original contour" (AOC) revealed that he was refemng to the pre-mining slope. This is an important distinction because the AOC is what Colowyo is defining in their proposal. AOC has a broad and ambiguous definition that deliberately uses terms like "closely resembles" and -general surface configuration" in order to introduce flexibility in the design. In the rules the Backfilling and Grading Section 4.14 also infers that the surface configuration can be above or below pre- mising topography in the final design. Colowyo believes their proposal meets all the requirements for AOC and Backfilling and Grading. Colowyo has made revisions to the post-mining topography (PMT) to accommodate CDMG suggestions. Again, in this submittal Colowyo has made revisions that take into account constructive improvements from CDMG. Within the arena of -reasonable and practical " Colowyo has compiled a final topography that meets both AOC and Backfilling and Grading requirements. Colowyo has reviewed the following information for this proposal in order to ensure compliance with the AOC and Backflling and Grading requirements: Volumetric Calculations For Meeting Th1ck Overburden Requirements Pre and Post Mining Slope Aspect D1strlbution and Comparison Pre and Post Mining Slope Distribution To Include The Following Statistical Measurements: Minimum Slope Maximum Slope Average Slope Median Slope Standard Deviation Number of Datum Spacing Pre and Post Mining Average Elevations Pre and Post-Mining Angle of Confluence for Drainages Adjacent Landtorms In The Area Geo-technical Stability Other Natural Resource Perspectives for Enhancing the Overall Reclamation Plan In conclusion the present design meets all requirements for AOC and Backfilling and Grading CF4.1.2.7 TR56