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2.04.6 (1d) <br />Reportedly, no significant water - bearing units were encountered during the course of <br />mine development and production at the New Elk Mine. Although sandstone units are often <br />regarded as "water- bearing ", the matrix of Raton Formation sandstone often consist of clay or <br />are often cemented thereby reducing the porosity and permeability of the rock. Reportedly, <br />"drippers" did occur during mining under some sandstone units but it dissipated soon after <br />mining progressed elsewhere. Reportedly, groundwater was minimal when the fault was <br />encountered in the northwest part of the mine and when the igneous intrusion was encountered in <br />the southeastern part of the mine. <br />As discussed in 2.04.6 (la), coal seams appear to be the most significant source of <br />groundwater but mining experience has demonstrated that it is effectively handled with proper <br />water management plans. <br />Approximately 50 CBM sites occur in the proposed permit area all of which have been <br />completed in the Raton and /or the Vermejo formation coal seams. This likely contributed to a <br />significant amount of dewatering of the coal seams planned for mining in the proposed permit <br />area. <br />The Golden Eagle Mine, located down -dip of the proposed permit area has likely <br />dewatered areas above the Maxwell Seam. The Allen Mine, located in the up -dip part of the <br />permit area has likely captured significant volumes of groundwater in the Allen and Apache <br />seams. As a result of this dewatering from mining and CBM production, groundwater issues <br />should be minimal within the proposed permit area. <br />Within the proposed permit area, no significant inflows were encountered during the <br />2010 exploration program. A considerable amount of packer testing was completed in the <br />northeastern part of the permit area at holes NE -1 -10 and NE -5 -10. Three monitoring wells were <br />established during 2010 to provide additional data and future monitoring of the groundwater. <br />These include wells NE -1 -10 completed in the Allen Seam, NE -6 -10A completed in the Apache <br />Seam and NE -6 -1013 completed in the Blue Seam. In -depth discussions on probable <br />hydrological consequences and monitoring plans can be can be found in section 2.05.6(3). <br />2.04.6 (le) <br />A thorough understanding of the coal seam stratigraphy and associated overburden and <br />floor lithologies have aided New Elk Mine in preparation of the subsidence control plan. As part <br />of the 2010 exploration plan, extensive geomechanical testing has been performed to <br />characterize the behavior of the rocks that will be subjected to mining. It must be emphasized <br />that vast areas of underground mining has already occurred in the proposed permit area and <br />historical subsidence data provides support for current subsidence predictions. The geological <br />information described throughout section 2.04.6 provides the geologic basis for the subsidence <br />control plan detailed in section 2.05.6 (6) of this permit document. <br />TR56 2.04 -11b Revised 4/15/11 <br />