Laserfiche WebLink
West Elk Mine <br />I, described in Section 2.04.7, the following springs will be added to the monitoring program 10-1, <br />E14-1, and 24-3. <br />('nncv~t~inl nacrr' lion Ctihcidvnra 7nYnartc rn ,Crri-no~c _ The key to evaluating whether or not <br />any given spring will be adversely affected by the B or E-Seam mining in the permit area is to <br />define its elevation relative to both the mine seam and the ground surface. Essentially, the higher <br />the elevation of a spring (and spring source), the smaller the probability of adverse impact as a <br />consequence of fractures that extend upwazd from the mine. However, for a spring to avoid <br />impacts from subsidence, in addition to being above the mine fracture zone, the source of the spring <br />needs to be faz enough below the ground surface to avoid surface fractures that may be the result of <br />subsidence. This phenomenon is described by Liane Kadnuck (U.SI Bureau of Mines) in her paper, <br />Response of Surface Springs to Longwall Coal Mining Wasatch Plateau, Utah, where she states, <br />"The limited spring response observed at this site may be attributed to several factors; (1) the <br />thickness and composition of overburden present which contained a massive competent sandstone, <br />which causes bridging in the overburden, limiting subsidence, (2) presence of formations <br />containing swelling clays, and (3) the elevation of the spring above the elevation of estimated <br />heights of fracturing and caving in the overburden." This basic condept is elaborated as follows. <br />~. <br />(. <br />2.05-l58 November 1004 PR/! <br />