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W/d:(2)SS1 1080 /770 1.40 <br />1080 /1220 0.89 <br />SS2 1080 /650 1.66 <br />1080 /1260 0.86 <br />SS3 1080 /390 2.77 <br />1080 /1250 0.86 <br />SS4 1080 /350 3.09 <br />1080 /1100 0.98 <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />Max <br />Min <br />(1) <br />(2) <br />(3) <br />(4) <br />(5) <br />(6) <br />(7) <br />(8) <br />(9) <br />14°14° <br />15 <br />5°5° <br />15 <br />TABLE 4 <br />MAXIMUM SUBSIDENCE PARAMETERS FOR <br />SUNSET TRAIL MINING AREA(1) <br />-Em (in terms of Sm/d) (7) <br />(-1.2 to -1.5 Sm/d) <br />0.047 0.074Mm (2.2 to 2.3 Sm/d) (6) <br />Em (in terms of Sm/d) (7) <br />(1.2 to 1.4 Sm/d) <br />0.0150.009 <br />0.021 <br />0.80.8 <br />-0.031 <br />Max <br />Min <br />Max <br />Min <br />Maximum Crack <br />Depth (8) <br />1 <br />2 <br />Parameter Panels SS1 - SS4 (t = 9 to 14 ft) <br />Max <br />Min <br />Min <br />Max <br />Angle measured from a vertical reference. <br />0.029 0.045 <br />0.005 0.008 <br />5 5 <br />-0.005 <br />10 15 <br />Break Angle (9) <br />Angle of Draw (9)19°19° <br />0°0° <br />Subsidence (maximum vertical displacement) above longwall panel centers, based on planned coal extraction thickness listed. <br />Ratio of the range of maximum vertical displacement to overburden depth range for the longwall panels. <br />Maximum range of tilt in terms of Sm/d; values of 2.2 to 2.3 Sm/d are obtained from the graph in Figure 5. <br />Maximum range of horizontal strain in terms of Sm/d; values for tensile (positive) strain of 1.2 to 1.4 Sm/d and compressive (negative) <br />strain of -1.2 to -1.5 Sm/d are obtained from the graph in Figure 5. <br />Maximum crack depth (in feet) in bedrock predicted to locally occur on or near steep slopes and ledges in the Minnesota Creek and <br />Lick Creek drainage areas and above barrier pillars and rigid chain (gate road) pillars. The first depth range (1) is for bedrock sloping <br />less than, or equal to, 30 percent; the second depth range (2) is for slopes more than 30 percent. Add 5 to 15 feet where thick, brittle <br />sandstones occur in ridges and near cliffs. No cracks are predicted to occur in alluvium. No cracks are predicted to occur at the <br />surface of colluvium thicker than about 10 feet. <br />All panels are numbered according to planned panel identifications. Because the tables provides for the full range of values, there is <br />no need to distinguish between Layouts A and B. <br />Subsidence and subsidence factor above chain pillars. <br />t = 9 ft t = 14 ft <br />Scp = acp • t (3) <br />(acp=Scp/t) <br />0.9 <br />0.3 <br />1.4 <br />0.3 <br />7.2 11.2 <br />0.1 0.1 <br />2.7 <br />Maximum tilt and strain parameters apply only to ground surfaces with slopes less that 30 percent; values may be greater on slopes <br />steeper than 30 percent. <br />4.2 <br />Sm = a • t (4) <br />8.45.4 <br />0.032 <br />0.6 0.6(a = Sm/t) <br />Sm/d (5) <br />0.004 0.007 <br />-0.008 <br />-0.048 <br />35 35 <br />G:\WWE\831-032\921\Engr\Exhibit 60E\Tables\ <br />Table 4 Sunset Trail.xlsx <br />Wright Water Engineers, Inc. <br />December 30, 2020 <br />Calc By: MO <br />Chkd By: JMK