2021-02-05_PERMIT FILE - C1980007A ‎(5)‎

• Permit No: C1980007A
• IBM Index Class Name: Permit File
• Doc Date: 2/5/2021
• 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: Yes

5
ES 4
3 ��Mm
2 //
O South of Divide
o +Em
® 0
€� o
-1 0
Em
-2 �
South of Divide
a
-4 0
-5
0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
W/d
Figure 5. Graph showing maximum tilt (Mm) and horizontal strain (Em) versus the mining panel
width to depth ratio (W/d). Tilt (circles) and horizontal strain (squares) for the West Elk Mine
subsidence monitoring network are shown with the average National Coal Board(1975) longwall
curves. New curves were developed for the South of Divide and Dry Fork mining areas.