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West Elk Mine <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 year. The <br />quality of mine water offers no problem for treatment and discharge. Mine water discharge is <br />treated in sedimentation pond MB -1." (p.38). <br />This remains true. Minor F -Seam colluvial inflows in the main entries are 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 are 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 />sumping 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 are not expected to have an impact on streams <br />as subsidence and propagation of fractures are to be minimized under the proposed Mine Plan <br />sections contained within the permit 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 miming the South of Divide permit revision area. <br />Rezional Mining 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 regarding the general hydrologic conditions and <br />consequences of milling 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 permit area: <br />1. "Four Cc« OiicS ";�:::%„� aquifers Occur In the Somerset coal field. T1ZeS? are; (a) The <br />_ r . _...._.. <br />alluvium and terrace deposits associated with the North Fork of the Gunrlison River; (b) The <br />localized, shallow alluvium along creeks tributary to the North Fork; (c) The discontinuous <br />lenticular and laminar sandstones of the Mesaverde Formation; and (d) The Rollins Sandstone.” <br />(p. 4). <br />2.05-180 Revised June 2005 PRI0, January- 2006, Alarch 2006; Rev. Mm, 2006 PRIG, Nov. 2006 TRI07; Sep. '007 PR12;Feb -'008 PR12 <br />