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<br /> <br />• 2.05.3(8) Coal Mine Waste and Non-Coal Processing Waste <br />51. Only one piezomerer was installed within the proposed location of the coal mine waste bank. A <br />water level was measured in this piezomerer in late October 1995 (driest time of the year). <br />The water level was measured in the Rollins Sandstone and is probably fairly static. However, <br />during the spring time, the overlying colluvium may become saturated at some depth above the <br />Rollins Sandstone. Does the potential exist for a perched water table above the Rollins <br />Sandstone? If a perched water table exists how will this effect the design and construction of the <br />underdrain rystem and operationally, will this have an adverse affect on the stability of the coal <br />mine waste bank. <br />Response: Water level readings from the referenced piezomerer indicate a stable water level <br />at approximately 50 feet below ground surface which does not exhibit significant seasonal <br />variation (ie: S1-feet on 12/4/95 and 48-feet on 5/28/97). Given the relatively steep <br />sideslopes of the proposed refuse pile area and the existence of relatively coarse <br />alluvial/colluvial materials in the drainage bottom, the potential for development of a <br />perched water table is considered negligible. <br />2.05.4 Reclamation Plan <br />52. The application narrative indicates the canyon walls surrounding the northernmost coal <br />stockpile will be stripped to accommodate the pile. Will there be any additional earthwork <br />cut/f:llJ at this area? <br />• Response: Given the existing valley configuration in this area, earthwork requirements will <br />be minimal. On the east side of the valley, minor sideslope cuts and grading will occur to <br />accommodate the Elk Creek culvert extension and create a relatively flat stockpile <br />foundation area to facilitate stockpiling and coal recovery operations. Similarly, minor cuts <br />and grading will occur on the west side of the valley to level the stockpile foundation. Map <br />3213 has been revised to reflect the minor grading which will occur in these areas. Please <br />see accompanying revisions. <br />53. Map E-3213 indicates a very large area will be disturbed and stripped of topsoil, which appears to <br />greatly exceed that which is necessary to construct the proposed structures. Please either reduce the <br />area to be stripped, or explain why the additional disturbance is necessary. <br />Response: The indicated topsoil stripping limits are conservative and actual stripping may <br />involve a reduced azea depending on conditions encountered during field operations. In the <br />area of the expanded coal stockpile, sideslopes will be stripped of topsoil to accommodate <br />additional stockpiling beyond the limits of the live stockpiles created by stacking cube <br />discharge as discussed in the permit revision. Stripping limits have been defined by <br />identifying the required operational disturbance azea and extending this area as necessary to <br />reflect the additional area necessary to blend reclaimed slopes with the surrounding terrain <br />during final site reclamation. While conservative, this approach assures that loss or <br />contamination of available topsoil resources will be minimized. <br />• 54. Map E-3213 shows that the conveyor between the 8 Seam Portal and the E[k Creek facilities will <br />be removed. Is this correct? <br />Response: The hatch pattern indicating facilities to be removed was erroneously applied to <br />the existing overland conveyor from the Sanborn Creek Mine portals to Conveyor Drive 2. <br />