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West E[k Mine <br />Impacts to wetlands are regulated under Section 404 of the Federal Clean Water Act. Section 404, <br />and the accompanying regulations (including in particular, the 404(b)(1) Guidelines) indicate that <br />proposed activities which result in dredging and/or filling regulatory wetlands need to obtain a <br />Section 404 permit prior to commencement of the activity. To qualify as a "regulatory wetland," the <br />land in question must meet specific requirements pertaining to vegetation, soils and hydrology. As <br />of March 1995, the criteria for these three parameters were being closely reviewed by the U.S. <br />Army Corps of Engineers (LISACE), U.S. Environmental Protection Agency (EPA), and a technical <br />committee of the National Science Foundation. <br />As noted above, if a pazty intends to dredge and/orfill in a regulatory wetland, a 404 permit must be <br />acquired in advance of the activity. Note that the regulatory "trigger" is dredging and/orfilling. No <br />such activities are proposed in the Apache Rocks,Box Canyon, or South of Divide permit revision <br />azeas. <br />To ascertain whether potential wetlands impacts caused by mining-induced subsidence would be <br />regulated under Section 404, MCC representatives met with staff from the U.S. Army Corps of <br />Engineers (USAGE), Grand Junction office in September 1994. In this meeting, USAGE staff <br />indicated that, at West Ells Mine, wetlands impacts as a consequence of subsidence would not be <br />regulated. In addition, due to the many reasons presented above regarding the general lack of <br />impacts to streams, spring/seeps and groundwater, it is unlikely that the wetlands in the South of <br />Divide permit revision area will be significantly affected by the mining. The wetlands in question <br />derive their water from surface drainages and spring/seeps. WWE's calculations indicate that the <br />• maximum potential spring and streamflow loss in the current pernut and Box Canyon permit <br />revision azeas is less than 3 acre-feet per yeaz. A loss of this magnitude, especially when distributed <br />over the full permit revision azea, is of no consequence relative to the wetlands. If the total annual <br />surface water and spring "losses" of 3 acre-feet were to reemerge downgradient, slope stability is <br />not likely to change significantly. The introduction of 3 acre-feet of additional groundwater <br />dischazge is smaller than the natural, yeaz-to-yeaz fluctuations in groundwater dischazges. This <br />finding, coupled with the small wetlands acreage in the Apache Rocks and Box Canyon permit <br />azeas, leads to the conclusion that the probable hydrologic consequences from the perspective of <br />wetlands aze not significant. <br />Water Rinhts <br />Backeround <br />This section discusses the potential effects on vested water rights that may be caused by MCC's <br />longwall mining operation, and the associated subsidence in the permit area. The location of the <br />South of Divide permit revision areas aze shown on Map lA. Related impacts include inflows from <br />faults and storing water in underground sumps. All of these topics aze addressed herein. <br />The water rights analysis has been prepared by WWE with over 40 years of experience in this <br />subject. WWE recommends that readers review the next major section of this report Mine Water <br />System for background to facilitate an understanding of water management at the mine, and <br />. associated water rights implications. <br />2.05-108 Revised June 2005 PRIO; Rev. March 2006; Rev. Apri12006 PRlO; May 2006 PRI G <br />