PERMFILE70463

• Permit No: C1980007
• IBM Index Class Name: Permit File
• Doc Date: 6/2/2006
• Section_Exhibit Name: Exhibit 60D 2004 Geologic Hazard Field Observ for the South of Divide Mining Area
• Media Type: D
• Archive: No

2004 Geologic Hazard Field Observations
South of Divide Mining Area

TABLE 1
Maximum Subsidence Parameters For
South Of Divide Mining Area t'I
•

Parameter Panels E7 - E4 (t = 8 to 14 ft) Panels ES - E8 (t =12 to 14 ft) Panel E9 (t =12 to 14 ft)
W/d: Max E1: 1080 / 625 = 1.73 E5: 1080 /500 = 2.16 E9: 1080 /500 = 2.16
Min 1080 / 1425 = 0.76 1080 / 1100 = 0.98 1080 /550 = 1.96
Max EZ' 1080 /400 ~ = 2T0 E6: 1080 /500 = 2.16
Min 1060 / 1100 = 0.98 1080 / 1200 = 0.90
Max E3: f 080 /500 = 216 E7: 1080 /550 = 1.96
Min 1080 / 1100 = 0.98 1080 / 1250 = 0.86
Max E4: 1060 / 40D = 270 E8: 1080 / 675 = 1.60
Min 1080 / 1025 = 1.05 1080 / 825 = 1.31
t=8ft t=14ft t=12ft t=14 t=12ft t=14
Sm=a~•t~ 0.80 to 2.4ft 1.4 to 4.2ft 1.2 to 3.6ft 1.4 to 42ft 1.2ft 1.4ft
{ay=Sm/t) (0.1 to 0.3) {0.1 to 0.3) (0.1 to 0.3) {0.1 to 0.3) (0.1) (0.1)
Sm,=a•tk~l 4.8 to6.4ft 8.4 to11.2ft 7,2 to 9.6 8.4 to112ft 8.4 to9.6ft 9.8 to11.2ft
(a = S„~t) (0.6 to 0.8) (0.6 to 0.8) (0,6 to 0.8) (0.6 to 0.8) (0.7 to 0.8) (0.7 to 0.8)
SmJd ts) 0.00377 to 0.00590 to 0.00576 to 0.00672 to 0.01527 to 0.01782 to
0.0160 0.0280 0.0192 0.0224 0.0192 0.0224
M~ (2.2 to 2.3 SaJd) k 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 (in terms of S,dd) m

(1.210 1.4 S,,,Id) 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
-E,,, (n terms of S°,/d) to
-0.004 to -0.024 -0.007 to -0.042 -0.007 to -0.029 -0.008 to -0.034 -0.016 to -0.029 -0.021 to -0.034
MaximumCradk 1 5-tOft 5-15ft 5-10ft 5-15ft 5-10ft 5-15ft
DepthjBl 2 10-ZOft 15-35ft 15-25ft 15-35ft 15-25ft 15-35ft
Break Anglet9t 0-5° 0-5° 0-5° 0-5° 0-5° 0-5°
Angle of thaw k~ 10 - ZO° 10 - 20° 10 - 20° 10 - 20° 10 - 20° 10 - 20°
k't Maximum Ott and strain parameters a on to and surfaces with sl
ppty ty gro open less that 30%; slues may be greater on
slopes steeper than 30 percent
l~ All panels are numbered acceding to planned panel identifications.
rn (Subsidence and subsidence factor above chain pillars.
H1 Subsidence (maximum vertical di~lacemem) above Iongwa0 panel centers, based on planned coal extraction thicgkess
fisted.
t~ Rafio of the range of maximum vertical displacement to overburden dep8r range for the nine planned longwall panels.
ke Maximum range of tilt in terms of Sm/d; values of 2.2 W 2.3 S„/d are obtained fran the graph in Figure 5 (Exhibit 60 B).
m Maximum range of horizontal strain in terms of Srr/d; values for tensile (positive) strain of 1.2 to 1.4 Sm/d and compressive
(negative) strain of -1.210 -1.5 S„Jd are obtained from the graph in Figure 5 (F~dribtt 606).
ka) Maximum sack depth (in feet) in bedrock predicted to locally occur on a near steep slopes and ledges in the Minnesota
Gleelk and Lick Creek drainage areas and above bonier pillars and rigid chain (gate road) pillars. The first depth range (1) is
far bedrock sloping less than, a equal to, 30 percent; the second depth range (2) is for steep tredrock sloping and difts more
than 30 percent No kxadks are predicted to ocwr in alluvium. No cracks are predicted to occur at the surface of ce0uvium
Itddcer than about 10 feet.
rn Angle measured fiorrr a vertpl reference.
831-032.621 Wright Water Fsgineers, Inc. Page 18
November 2004