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the previously provided volume calculations. Table 2.05.2-2 is provided with this submittal <br />and shows the coal and overburden volumes to be encountered. Also see response to <br />Comments 16 and 17 regarding the temporary and permanent fill volumes. <br />Rule 2.10 - Maps <br />4. Colowyo has provided a new map with the submittal of TR-81, Map 45 - South <br />Taylor Fill. This map shows the locations of the permanent East Taylor and West Taylor <br />Fills as well as the locations of the three temporary overburden stockpiles (one on the West <br />Taylor Fill, one on the East Taylor Fill and one on the backfill in the final cut of the Section <br />16 Pit). This map also shows several cross-sections through the piles. The Division does <br />not understand why Colowyo has included cross-section E-E', which runs basically north- <br />south. This cross-section parallels cross-section A-A' and is only 100 feet to the east of <br />cross-section A-A' (cross-section E-E' is also approximately 460 feet shorter than cross- <br />section E-E'). A more useful cross-section that is missing from the map would be a cross- <br />section that runs across both the Section 16 temporary overburden pile and the East Taylor <br />Fill, in a southeast to northwest direction. Another cross-section that would be useful (in <br />lieu of cross-section E-E') would be one that cut across the West Taylor Fill, the East Taylor <br />Fill and the Section 16 temporary overburden pile in a west to east direction. Please <br />explain why Colowyo has provided the two seemingly identical cross-sections A-A' <br />and E-E' on Map 45. Please provide,at least one north-south cross-section that <br />covers the three piles. Please update Map 45 as necessary based on the review of <br />the cross-section lines shown. <br />Response: Cross section A-A' was developed to show the approximate center of the East <br />Taylor Fill at its deepest section, which is slightly below the sub-crop line of coal seams E <br />and F. Adjacent cross section E-E' was developed to show the coal seams E & F that have <br />been mined out under the fill, which cross section A-A' would not show. Since cross- <br />section E-E' was not a critical section for slope stability analysis, is therefore not essential, <br />and apparently raises some confusion. It has been deleted. <br />However, a new cross section E-E' has been provided, which is runs in an east-west <br />direction covering the full extent the temporary spoil piles. We believe the intention of <br />CDRMS' Comment No. 4 regarding provision of at least one "north-south" cross-section <br />covering the three piles was really intended to suggest the need for an "east-west" cross <br />section, which is what the new cross-section E-E' on Map 45 provides. <br />5. Map 19B - Postmining Topography - South Taylor Area <br />a. Please add stationing tick-marks to the cross sections. <br />Response: Stationing tick-marks have been added to Map 198. <br />b. A portion of slope located approximately 1000' west of the "20" appears to be <br />steeper than 3H:1 V. Section 2.05.4(2)(c) Backfilling Plan for South Taylor/Lower Wilson <br />states the Colowyo will grade all final slopes so that overall grades do not exceed 33% <br />(3h:1v). Please review the proposed postmining topography to ensure that no <br />slopes will exceed 33%.