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

Figure 12. Subsidence development curves relative to a point (P) from the 5NW longwall panel
at the West Elk Mine (squares), and Somerset room-and-pillar (circles, subsidence more than 90
percent complete and triangles, subsidence only 60 percent complete) as compared to the average
National Coal Board curve (1975). This relationship is shown as the ratio of subsidence to
maximum subsidence (S/Sm) versus the ratio of face position to overburden depth (X/d).