2021-02-05_PERMIT FILE - C1980007A ‎(4)‎

• Permit No: C1980007A
• IBM Index Class Name: Permit File
• Doc Date: 2/5/2021
• Doc Name: STREAM CHANNEL PARAMETERS
• Section_Exhibit Name: Exhibit 55B Stream Channel Parameters and Changes Due to Mining-Induced Subsidence
• Media Type: D
• Archive: Yes

TABLE 4
EFFECTS OF SUBSIDENCE ON STREAM CHANNELS
Basin Pre-Mining Slope (%) Maximum Subsidence Change in Slope Post-Mining Slope(3)
Number Average Lower (E-seam + B-seam)(2) Maximum Maximum Minimum Maximum
Reach (') (ft) Negative Positive
3 11.1% 15.5% 8.3 -2.9% 10.6% 4.8% 18.3%
29 9.7% 4.8% 14.7 -5.1% 2.0% 2.8% 9.9%
32 8.5% 4.0% 14.3 -3.5% 2.4% 1.6% 7.5%
35 5.3% 5.6% 15.2 -2.1% 3.5% 2.1% 7.7%
36 7.1% 5.9% 6.5 -4.4% 2.3% 3.7% 10.3%
37 8.3% 5.4% 13.4 -3.0% 1.7% 3.7% 8.4%
39 15.9% 8.6% 9.2 -6.6% 1.5% 7.0% 15.2%
41 30.0% 25.3% 9.2 -3.0% 1.8% 23.5% 28.3%
This refers to the lowest reach potentially impacted by mining.
(2) Basins 3, 36, 39, and 41 are only affected by E-seam mining.
(1) Slope range given for lowest reach potentially impacted by mining.
G:\WWE\831-032\921\Engr\Exhibit 55B\ Wright Water Engineers,Inc. Prprd By:AWP
MCC_subsidence_5513_2020_Tables.xlsx\Table 4 December 23,2020 Chkd By:JMK