2021-05-27_PERMIT FILE - C1981019A ‎(7)‎

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 5/27/2021
• Doc Name: Addendum Collom and South Taylor Highwall Mining Geotechnical Design
• Section_Exhibit Name: Volume 20 Exhibit 27 Item 7
• Media Type: D
• Archive: Yes

Mr. Lee Sampson
April 23, 2021
Page 13
Design Mining Height, ft
Depth of Cover, ft 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11
130 71.6 70.5 69.0 67.4 65.8 64.5 63.1 61.7 60.3 59.1 58.1 56.9 55.8
160 68.6 67.5 66.5 65.5 64.5 63.6 62.4 61.0 59.7 58.4 57.5 56.3 55.2
190 66.1 64.8 63.8 62.6 61.7 60.8 59.7 58.9 58.1 57.4 56.6 55.7 54.5
220 63.8 62.6 61.4 60.2 59.4 58.3 57.2 56.5 55.5 54.8 53.9 53.2 52.6
250 62.4 60.71 59.4 58.21 57.2 55.91 55.0 54.2 53.41 52.5 51.6 50.81 50.2
280 60.6 59.4 58.0 56.6 55.5 54.2 53.1 52.2 51.3 50.3 49.6 48.8 48.1
310 58.9 57.6 56.3 55.1 54.0 52.8 51.8 50.7 49.7 48.7 47.9 46.9 46.2
340 56.7 55.7 54.7 53.5 52.4 51.4 50.4 49.4 48.4 47.4 46.5 45.7 44.8
370 54.9 53.9 52.7 51.6 50.8 49.8 48.8 47.7 46.8 46.0 45.2 44.4 43.6
400 53.1 52.0 50.9 49.9 48.9 48.1 47.2 46.3 45.5 44.51 43.8 43.0 42.2
430 51.7 50.41 49.21 48.21 47.1 46.3 45.4 44.6 43.91 43.21 42.4 41.6 40.9
460 50.1 48.8 47.6 46.61 45.7 44.7 43.91 43.0 42.21 41.51 40.8 40.2 39.5
490 1 48.7 47.41 46.11 45.11 44.1 43.2 42.31 41.5 40.71 40.01 39.2 38.6 38.0
Coal strength, psi 900 Mining width, ft 11.50 No. web pillars 19
75
70
Mining
Height,
ft
65
mrI 5
5.5
60 1t
- 6
�I �6.5
�7 55 �Ti 4 -7
O 7.5
?i 50 + 8
i8.5
45 +- 9
I+ -9.5
-10
40 L
10.5
11
35
30
130 160 190 220 250 280 310 340 370 400 430 460 490
DEPTH OF COVER, ft
Figure 4c. Raw RecoveryCollom C3/C5 Seam
Agapito Associates, Inc.