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Wesr Elk Mine <br />• elevation of the mine opening are drained. The inflows from the faults reach equilibrium at 50 to <br />125 gpm existing as floor springs until the fault zone is breached again at a lower elevation with <br />subsequent development. Down dip inflow rates from the fault zones are dependent upon the <br />displacement and damage zone extents, the incremental head (vertical elevation change), and linear <br />distance from the last fault intercept. Each new down dip intercept dries up the previous floor <br />spring. Up dip inflows from the faults have been limited to short-lived nuisance roof water at less <br />than 10 gpm with no sustained water flows from the faults. <br />E Seam mining will encounter many of the same fault systems and possibly one inferred zone not <br />intercepted in the B Seam. Mayo (2004) projects the previously intercepted fault zones may have <br />insignificant nuisance waters associated with the fault zones but inflows from either Rollins or <br />Bowie sandstones will be small or non-existent. The exception may be where tectonic faults have <br />crossed sandstone roof channels allowing the channel and fracture damage zones to store water. <br />Inflows from the sandstone channels may reach 500 gpm in that instance. Inflows into the E Seam <br />mine workings may reach 500 gpm from un-intercepted tectonic faults. This value reflects possible <br />damage zone widths, distance to outcrop, and vertical elevation. Dr. Mayo's report, Evaluation of <br />Potential Groundwater Inflows Associated with E Seam Mining, West Elk Mine, Somerset, <br />Colorado, is available at West Ells Mine. <br />An unknown source of groundwater is the Mt. Gunnison intrusive located to the southeast of the <br />main body of the E Seam reserve. Groundwater may be stored in fractures and strata on the edge of <br />the intrusive sourced from rain and snowmelt. Drill hole and seismic data is limited to the southeast <br />due to topographic and political constraints (EO seam thickness is diminishing to 8 feet and thinner <br />to the southeast). For these reasons and others the E Seam mine plans has not been projected to <br />within 5000 feet of the intrusive body. Additional drilling in 2005 and beyond will assist in <br />determining the groundwater inflow potential. <br />Inflows to the E Seam will be similar in magnitude to those observed in the current B Seam <br />mining azea. The reasons for this finding include: <br />Similaz overburden depths. <br />Similaz lithologic units within the overburden. <br />Plans to mine the E Seam as it has mined the B Seam. <br />Inflows to the E Seam aze expected to be by the same mechanisms as those identified for the <br />B Seam. <br />Fault and non-fault related groundwater inflows into the E Seam workings may occur from <br />two potential sources (Exhibit 18B): <br />1. Overlying sandstone channels <br />2. The underlying Bowie Sandstone <br /> <br />1.05-177 RevisedJwie 1005 PR/0; Rev. March 1006: Rev. May 1006 PRI G <br />