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To examine the influence of surface topography on ground movements at BRL, we <br />have superimposed subsidence contours and overburden thickness contours for three <br />monitoring time frames over the longwall block as illustrated in figures 6 through 8. In <br />addition, the location of geologic structures is shown together with horizontal <br />displacement vectors. The subsidence contours are influenced by wide, irregular <br />monument locations selected to accommodate steep topographies; nevertheless, we <br />consider the contours useful for these comparisons. Excluding multiple-seam mining <br />areas, the maximum subsidence of 7.5 ft occurred in panel D8 at monument location 22D <br />at the higher topographies (figure 6). In contrast, at lower topographies along panel D7, <br />subsidence was much reduced, to 5.5 ft at monument 14D. Assuming good surveying <br />practice, this pattern of movement is consistent with the pile-up effect observed in the <br />Raton basin. <br />Results clearly show horizontal displacements concentrating at topographic highs. <br />• Over the western panel boundaries at topographic highs, ground moved downhill to the <br />east and movement diminished at topographic lows near Hubbard Creek (figure 6). <br />Similarly, horizontal movement increases significantly toward the Freeman Gulch <br />drainage area as the monuments to the north and south of the gulch moved toward the <br />drainage at low elevations. This creates compression at the bottom of the drainage. The <br />topography is dominating patterns of horizontal movement. <br />Figure 7 presents similar results after the 2003 survey. During this period, the <br />operator extracted three longwall panels (D4, D5, and D6). The ground moved eastward <br />at the western boundary of the longwall panels and became insignificant near Hubbard <br />Creek. Maximum horizontal displacement is now toward the Sheep Corral. BRL <br />geologic staff mapped several short faults in this area, here referred to as the D6-D9 <br />faults. These faults do not extend to the surface and thus are not believed to have <br />influenced horizontal movement significantly. Figure 8 presents similar results from the <br />2004 survey after the extraction of the D9 panel. Horizontal movement was pointed <br />. downhill toward the Sheep Corral and slightly magnified during this monitoring period. <br />Maleki Technologies, Inc. Page 20 <br />