PERMFILE52001

• Permit No: C1980007
• IBM Index Class Name: Permit File
• Doc Date: 6/2/2006
• Section_Exhibit Name: Exhibit 60B Subsidence Evaluation for the South of Divide Mining Area
• Media Type: D
• Archive: No

TABLE 2
. MAXIMUM SUBSIDENCE PARAMETERS FOR
SOUTH OF DIVIDE MIIVING AREA to

Parameter Panels E1 - E4 (t = 8 to 14 R) Panels E5 - E8 (t =12 to 14 R) Panel E9 (t =12 to 14 R)
W/d: Max
Min Et: 1080 /625 = 1.73
1080 / 1425 = 0.76 E5: 1080 /500 = 2.16
1080 / 1100 = 0.98 E9 1080 /500 = 2.16
1080 !550 = 1.96
Max
Min F2: 1080 /400 = 2.70
1080 / 1100 = 0.98 E6: 1080 /500 = 2.16
1080 / 1200 = 0.90
Max
Min E3: 1060 /500 = 2.16
1080 / 1100 = 0.98 E7: 1080 /550 = 1.96
1080 / 1250 = 0.86
Max
Min E4: 1060!400 = 2.70
1080 / 1025 = 1.05 E8: 1080 /675 = 1.60
1060 /825 = 1.31
t=8ft t=14R t=12ft t=14ft t=12R t=14ft
S~=a~•t~
(a~~~lt) 0.80 to2.4ft
(0.1 to 0.3) 1.4m42ft
(0.1 m 0.3) 1.2 to3.6ft
(0.1 To 0.3) 1.4 to4.2ft
(0.1 to 0.3) 1.2ft
(0.1) 1.4ft
(0.1)
Sm=a•tk~i
(a = S,,,It) 4.8 to6.4ft
(0.6 to 0.8) 8.4 to112ft
(0.6 to 0.8) 7.2 to 9.6
(0.6 to 0.8) 8.4 to112ft
(0.6 to 0.8) 8.4 to9.6ft
(0.7 to 0.8) 9.8fo11.2ft
(0.7 b 0.8)
~d 1st 0.00377 to
0.0160 0.00590 to
0.0280 0.00576 to
0.0192 0.00672 fD
0.0224 0.01527 to
0.0192 0.01782 m
0.0224
Mm (22 fo 2.3 S,,,Id) ~ 0.007 to 0.037 0.013 to 0.064 0.013 to 0.044 0.015 to 0.052 0.034 to 0.044 0.039 to 0.052
Em (m terms of S,,,/d) m 0.004 to 0.022 0.007 to 0.039 0.007 to 0.027 0.008 to 0.031 0.018 to 0.027 0.021 to 0.031
-Fy„ (m firms of S=/d) to -0.004 m -0.024 -0.007 to -0.042 -0.00710 -0.029 -0.008 to -0.034 -0.018 ro -0.029 -0.021 to -0.034
MaximumCradc 1 5-10ft 5-15ft 5-10ft 5-15ft 5-10ft 5-15ft
~~~ 2 10-20ft 15-35ft 15-25ft 15-35ft 15-25ft 15-35ft
BrealkAngle~ 0-5° 0-5° 0-5° 0-5° 0-5° 0-5°
Angle of Draw c4 10 - 20° 10 - 20° 10 - 20° 10 - 20° 10 - 20° 10 - 20°
rr) Maximum 611 and strain parameters apply only to ground surfaces with slopes less [fiat 3fl percent values may be greater on slopes
steeper bran 30 percent
c4 All panels are numbered according to planned panel identifications.
r'l Subsidence and subsidence fadar above chain pillars.
kq Subsidence (maximum vertical displacement) above lorrgMrati panel centers, based on planned coal extraction thikimess listed.
kA Ratio of Ere range of maximum vertical displaoemeM to overburden depth range far Ere nine planned lorgrrall panels.
~ Maximum range of trlt trr terms of Smld; values of 22 to 2.3 5,°/d are obtained Tram the graph in Figure 5.
m Maximum range of har¢ontai strain in temrs of S„pld; values for tensile (positive) strain of 12 to 1.4 Smld and compressive
(negative) strain of -1.2 to -1.5 S=/d are obtained Tram the graph in Figure 5.
m Maximum crack depth (in feet) in bedrock pnafcted to IokaOy ocaa on or near steep slopes and ledges in the Minnesota Creek and
Lidk Creek drainage areas and above barrier pillars and rigid drain (gate road) pillars, The first depth range (1) is for bedrock
sloping less than, or equal to, 30 percent ttne second depth range (2) is for skrpes more than 30 percent. Add 5 to 15 feet where
thick, brittle sandstones ocwr in ridges and near difts. No kxadks are predicted to occur in alluvium. No aadks are predicted to
ocau at the surface of a>Ilwium thikiker than about 10 feet
m Angle measured Tram a viertinl reference.
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