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2. PR-6 application page 3-38a discusses the timing of the Kimber Pit. The text notes that the <br />truck/excavator pit will be divided into three main blocks (A, B, and C) with mining beginning <br />in Block B, Pit 1. According to the information presented on Map M10A Sheet 3 of 3, the <br />timing identifies mining beginning in what would be the A block of the Kimber Pit. <br />Please revise either the map or the text to identify the timing in which the Kimber <br />truck/excavator block will be mined in accordance with Rule 2.05.3(2)(a). <br />3. It is noted that the Air Pollution Control Division Permit I IMF253-1 was modified and issued <br />November 7, 2008. <br />Per Rule 2.03.10, please provide an update to PR-06 submittal page 1-9 to reflect the recently <br />issued permit. <br />4. Un-numbered pages discussing Horse Fill and K/G Pit Buttress Fill provided in the PR-06 <br />submittal contain information concerning a description of the proposed fills. <br />Please incorporate the un-numbered pages into the Trapper Mine Permit per Rule 2.05.3(6)(b). <br />The description should include descriptions of the geotechnical investigations, design, <br />construction, operation, maintenance and removal of the proposed fills as applicable. <br />Based on Appendix A of the Agapito Report entitled Horse Gulch Fill Stability Analysis, <br />December 2008 (The Report), the Horse Gulch Fill is a valley fill by definition. Per Rule <br />1.04(148), a valley fill "means a fill structure consisting of any material other than coal waste <br />or organic material that is placed in a valley where the side slopes of the existing valley <br />measured at the steepest point are greater than 20 degrees or the average slope of the profile <br />of the valley from the toe of the fill to the top of the fill is greater than 10 degrees." Appendix <br />A, Horse Gulch General Arrangement, shows three areas highlighted in yellow that exceed <br />35% slope (19.17 degrees). Preliminary calculations indicate an average slope for the drainage <br />profile of 8.6% (4.5 degrees). Given that some side slope areas are represented as exceeding a <br />19 degree slope, Horse Gulch Fill meets the requirements of a valley fill due to the side slopes <br />likely exceeding 20 degrees in places. Therefore, the requirements of 4.09.1 and 4.09.2 apply. <br />Please discuss whether you agree with this determination. It may be determined that the Horse <br />Gulch Fill may also meet the definition of a head-of-hollow fill [Rule 1.04(56)], in which case <br />the additional requirements of 4.09.3 may also apply. A final determination of fill category <br />will be determined by the DRMS engineer who reviews the submittal. Please discuss your <br />position as to whether or not the Horse Gulch Fill may also meet the definition of a head-of- <br />hollow fill. <br />6. Page 23 of the Horse Gulch Fill Stability Report, states that there will be no need to channel <br />storm runoff away from the fill once the fill is constructed. The Division does not agree with <br />this statement. Small areas south of the fill will flow north toward the fill and require diversion <br />into channels designed for the 100 year, 24-hour storm event. (Rule 4.09.2(7)) <br />Additionally, Rule 4.09.2(7) requires that drainage from the fill be diverted into channels <br />designed for the 100-year, 24-hour storm event. No diversion of flow from the fill is proposed