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West Etk Mtrre <br />is no reason to expect groundwater quality to significantly change if groundwater drops from one <br />formation to a lower formation. The technical literature is supportive on this finding. <br />12. "Total mine water inflow in the F-Seam has not exceeded 15 acre-feet in any one yeaz. The <br />quality of mine water offers no problem for treatment and dischazge. Mine water dischazge is <br />treated in sedimentation pond MB-1." (p.38). <br />This remains true. Minor F-Seam colluvial inflows in the main entries aze collected in small, open <br />depressions in entries and/or crosscuts (i.e, operational sumps) typically containing less than 0.10 <br />acre feet and aze pumped either to Sylvester Gulch or the main mine site sedimentation ponds for <br />discharge. As very little water was encountered when the F-Seam was mined, no operational <br />Bumping was needed during mining. Also, no water (including B-Seam inflows) has ever been <br />pumped into the sealed F-Seam workings for storage. It is important to note that the majority of F- <br />Seam panels were mined in areas up-dip (i.e., uphill) of the main F-Seam entries, so that water, if <br />any, would flow out and could not be held within the ventilation seals. <br />13. "Life of Mine Operations in F, B, and E-Seams aze not expected to have an impact on streams <br />as subsidence and propagation of fractures are to be minunized under the proposed Mine Plan <br />sections contained within the pen-nit application." (p. 34). <br />This statement certainly applies to the Apache Rocks permit revision area and the associated B and <br />E-Seam mining for the many reasons listed in Section 2.05.6, Surface Water Quantity Effects, <br />• Streams. This statement also applies to B-Seam mining in the Box Canyon permit revision area. <br />In 1998, CDMG approved the Box Canyon permit revision (PR08) for West Elk Mine. Much <br />of the information contained in the Box Canyon Decision Document (CDMG 1998) regarding <br />the current permit area is directly applicable to the probable hydrologic consequences <br />anticipated as a result of mining the South of Divide permit revision area. <br />ReEional Minine Experience <br />Considerable mining of the coal-bearing units within the Mesaverde Formation has occurred, not <br />only at West Elk Mine, but along the North Fork Valley. As a result, there is substantial <br />information known about the hydrologic consequences of mining the coal-bearing units within <br />this formation. <br />The CHIA (2001} provides a valuable summary regazding the general hydrologic conditions and <br />consequences of mining in the North Fork Valley. The following statements (including page <br />references) are included in this document. Unless otherwise noted, and based upon WWE's <br />analyses, these statements apply directly to the pemut area: <br />1. "Four categories of potential aquifers occur in the Somerset coal field. These are; (a) The <br />alluvium and terrace deposits associated with the North Fork of the Gunnison River; (b) The <br />localized, shallow alluvium along creeks tributary to the North Fork; (c) The discontinuous <br />lenticulaz and laminaz sandstones of the Mesaverde Formation; and (d) The Rollins Sandstone." <br />(p. 4). <br />2.05-180 Revised June 2005 PR/0, January 2006, March 2006; Rev. May 1006 PRIG <br />