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be captured by the pit and have not way to drain to the cutthroat trout habitat downstream. <br /> Please describe how stream capture is to be avoided. <br /> The mining plan has been revised to be shallower. As part of this,the north end of the main pit <br /> (Area 2)will be opened to the north, allowing flood waters to drain downstream into <br /> Hardscrabble Creek. A small berm will be maintained across this opening during mining to <br /> prevent the discharge of sediment. A small opening in the berm, either a weir or a valved pipe, <br /> will be used to allow clean water to discharge as needed. <br /> 3. Area 7:Area 7 shown on Exhibit C-1 does not appear to have any access/haul roads. <br /> Access and haul roads are considered affected area. Furthermore, it appears highly <br /> probable Area 7 access will require crossing the drainage (Mineral Creek?)for access. If <br /> the creek is to be crossed, the Division will require engineering designs based upon <br /> appropriate hydrologic and hydraulic analyses for these crossings. Please provide the <br /> following: <br /> a. Haul/access road routes on Map C-1, <br /> b. Engineering designs and analyses to support the crossing design(s). <br /> Mining in Area 7 will not be conducted until engineering designs for a crossing have been <br /> developed and approved by DRMS through the technical revision process. <br /> 6.4.4 EXHIBIT D—Mining Plan <br /> 4. Depth of mining vs. groundwater: The second paragraph indicates mining may go as deep <br /> as 35 feet below ground. The well(No. 0513192) shown on Exhibits C and F indicates <br /> groundwater is as close as 10 feet below the surface. The last paragraph on page D-2 <br /> states groundwater is 17—24 feet below the surface. Given the mine plan also states if any <br /> groundwater exposed, it will be backfilled to two feet above the elevation of the <br /> groundwater. This information suggests mining should not extend more than 15—22 feet <br /> below grade. Please provide some clarification and/or edits to the text in Exhibit D and <br /> maps in Exhibits C and F. <br /> Maximum mining depth will be roughly 20 feet, assuming no groundwater is encountered. This <br /> is based on the operator's experience within the existing pit. See the revised Exhibit D. <br /> 5. Topsoil and overburden handling: Section 4 on page D-5 provides maximum heights and <br /> side slopes (2H.-1 V)for topsoil and overburden stockpiles. However, unless these stockpiles <br /> are to be one-sided(the flat topography of the site suggests this is unlikely), these stockpiles <br /> will need to be twice as wide as stated in the text. For example, the 20 foot high topsoil <br /> stockpile will extend 40 feet in both directions from the crest, making it 80 feet wide, not 40 <br /> feet as indicated. Please revise the text for the widths of the topsoil and overburden <br /> stockpiles. <br /> See the revised Exhibit D. <br /> 6.4.5 EXHIBIT E—Reclamation Plan <br /> 6. Highwall length limit: The first paragraph states no more than 200 feet of highwall will <br /> remain unbackfilled at any given time. This approach seems highly impractical. First, <br /> Yevoli Cobblestone CN-01 2 (,«g i ra cki and \ssou.drs.PI t <br />