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1 <br /> panels in the southwestern portion of the mine, maximum subsidence values <br /> typically range fmn 1.5 to 2 feet. <br /> 4.5 Coubined Results - Multi-Seam Model <br /> A multi-seam model of the ombined subsidence from both the "B" and the "C" <br /> seam was produced by adding the respective "B" seam and "C" seam grids, point for <br /> point. This model produced a maximum subsidence of just over 5.3 feet. Once <br /> again, this maximum subsidence is likely to occur in the panels adjoining the <br /> outcrop barrier pi11dF in the northwest portion of the mine. <br /> The computer model also produced a grid consisting of the final <br /> post-subsidence surface elevations and a review of this data indicates no grade <br /> reversals or other significant disruption of drainage on the surface. In this <br /> rugged and steeply sloping terrain, even five or more feet of subsidence will be <br /> very difficult to detect visually. <br /> 4.6 Estimated Horizontal Ground Strains <br /> Using the subsidence data obtained fron the computer modeling, we estimated <br /> curvature and the associated ground strains using a proportionality constant k of <br /> 41.3 meters -1 (Hood et. al., 1982) . Based on these estimates, the horizontal <br /> ground strains in the vicinity of the naxiimun anticipated subsidence ranges from <br /> a maximum tensile strain on the order of 1.2 percent to a maximum compressive <br /> strain on the order of 1.0 percent. In areas of lesser subsidence (i.e. , further <br /> to the south) ground strains will typically range between 0.2 percent and 0.5 <br /> percent for both tensile and coupressive strains. <br /> Tensile ground strains as large as 1.2 percent are certainly large enough to <br /> E <br />