2022-09-29_PERMIT FILE - C1980007 ‎(5)‎

• Permit No: C1980007
• IBM Index Class Name: Permit File
• Doc Date: 9/29/2022
• Doc Name: SUBSIDENCE EVALUATION
• Section_Exhibit Name: Exhibit 60E Subsidence Evaluation for the South of Divide and Dry Fork Mining Areas
• Media Type: D
• Archive: No

TABLE 1
MAXIMUM SUBSIDENCE PARAMETERS
FROM WEST ELK MINE SUBSIDENCE MONITORING NETWORK
Parameter Longitudinal Profile
So. End 1 NW LW
Longitudinal Profile
No. End 1 NW LW
Transverse Profile
Above 2,3 NW LW W/d 750/1240=0.6 750/1350=0.56 2 NW: 750/1000=0.75
3 NW: 750/900=0.83 acp=Scp/t N/A N/A 0.20 to 0.35 a=Sm/t 6.94/12=0.58 6.06/11.5=0.53 2 NW: 0.62
3 NW: 0.58 Sm/d 0.005597 0.004489 2 NW: 0.00729
3 NW: 0.00762 Sm/d2 0.000004514 0.000003325 2 NW: 0.00000729
3 NW: 0.00000847 Mm 0.015
(2.7·Sm/d)
0.014
(3.1·Sm/d)
2 NW: 0.014
3 NW: 0.021
Cm(1)
0.000065
(14.4·Sm/d2)

-0.000111
(-24.6·Sm/d2)
0.000060
(18.0·Sm/d2)

-0.000066
(-19.9·Sm/d2)
2 NW: 0.00022
3 NW: 0.00014

2 NW: -0.00025
3 NW: -0.00012 Em

0.0070
(1.25·Sm/d)
0.0058
(1.3·Sm/d)
2 NW: 0.0102
3 NW: 0.0085
-0.0047
(-0.8·Sm/d)
-0.0009
(-0.2·Sm/d)
2 NW: -0.0236
3 NW: -0.0307 Maximum
Crack Depth(2)
80 feet 100 feet 50 feet
Break Angle(3) 32percent
Slope -
-9° Slope in same
Direction as tilt
42percent Slope -
3° Slope in opposite
Direction to tilt
—
Angle of
Draw(3)
17°(4) 15°(4) —

Notes:
(1) Numerical curvature values are in radians per foot (rad/ft).
(2) Maximum crack depth is projected for hard, brittle sandstones; depth is expected to be much less, or non-
existent, in soft, ductile shales and claystones.
(3) Measurement from vertical reference.
(4) Measurement takes into account influence of development entries, chain pillars, and prior F-seam mining.