2010-06-21_REVISION - C1981008 (2)

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C-1981-008 PR-06 June 21, 2010 Page 9 of 30 34. The Division's original question remains. According to the first paragraph of the new proposed Western Mining Area Backfilling section on pages 6 and 7, "The maximum slope in this area is 5H:1 V with a few exceptions, which is very good for the post mine land use of dryland pasture." This sentence does not clearly describe the topography as shown on revised Map 2.05.4-1. While 5H:1 V may be the steepest slope, it is not representative of the overall topography. WFC revised the text the May 2010 submittal, but it is not sufficient. In addition to describing the steepest slopes, please provide a description of the overall topography of the WFC parcel, including any elevation and grade changes that have been made from the pre-mining configuration; proposed gradients of irrigable lands; and any changes to surface drainage patterns. 35. The second paragraph of the Postmining Topography section on page 9 uses the term "typical" to describe the cross sections shown on Map 2.05.4-1. WFC has deleted the word "typical" as requested. Please delete the word "existing" from the fourth sentence of the same paragraph, describing the information shown on these cross sections. 36. In the Division's January 22, 2010 letter we requested WFC to submit the Post Mine Overburden and Backfill Balance Table. WFC provided a table, but many questions remain regarding the final material balance. We have the following questions regarding the material balance issues in Section 2.05.4(2)(c) - Backfill and Grading. Our evaluation included a review of- • Map 2.05.2-1 - Estimated Area for Life of Mine - Mine Plan • Map 2.05.3(3)-2 - Operations Plan - Variance to Leave Turn Slot - Life of Operation • Map 2.05.4-1 - Existing & Projected Reclamation Contours • Map 2.05.4-1-2 - Western Mining Area Post Mine Topography & Mining Sequence A. Currently Approved: The currently approved version (TR-54) of May 2.05.2-1 shows individually numbered mining cuts arrayed across the entire permit area. Moving west from 2700 Road to the far western boundary, the 43 cuts are numbered 68 through 111. In addition to the numbered cuts, the years during which mining of each series of cuts are projected to occur have been delineated (2004 - 2014). May 2.05.3(3)-2 of the permit includes the same configuration of mining cuts west of 2700 Road (68 through 111). PR-06 Application Nov-2009: A revised Map 2.05.2-1 was submitted with the original PR-06 application in Nov-2009. Without explanation, the numbered mining cuts had been removed from the new version. May 2.05.3(3)-2 was also revised (permit boundary only) with the PR-06 Nov-2009 application, but the original mining cut sequence was retained (68 through 111), as were the projected years (2004 - 2014). The PR-06 Nov-2009 application also included an entirely new map: Map 2.05.4-1-2. The Nov-2009 version showed a series of 31 cuts numbered 1 through 31, with cut 1