2009-11-08_PERMIT FILE - C1980007

• Permit No: C1980007
• IBM Index Class Name: Permit File
• Doc Date: 11/8/2009
• Doc Name: Coal Preparation Plan and Associated Coal Handling Facilities
• Section_Exhibit Name: Exhibit 81
• Media Type: D
• Archive: No

Table 1. PR-2 Conveyor Slope Stability Analysis Results
W ithout Bench Cut With Bench Cut

Station
Stabilization Required?
(Previous Evaluation) Distance from
Conveyor
Alignment [ft]
Factor of
Safety Stabilization
Required? (Current
Evaluation)
Distance from
Bench Edge (ft]
Factor of
Safety Stabilization
Required? (Current
Evaluation)
0 NO 44.8 1.180 No cut' 1.180 NO
1 MAYBF 21.9 1.100 YES 25.0 1.295 MAYBF
2 MAYBE 19.9 YES 23.0
1,070 1.293 MAvRE
3 MAYBE 26.0 _
YES 29.0
1.130 1.299 MAYBE
4 MAYBE 35.5 _
YES 37.0
1.160 1.305 MAYBE
5 AI. P,1 29.7 _
1.150
YFS 38.0 1.305 MAYBE
6 YLS 0.0 _
0.990 YES 27.0 1.297 MAYBE
7 YES -27.2 0.990 _ YES _ 10.0 1.160
8 YES -17.0 YES 33.0
0.990 1.300 MAYBE
9 YES -18.0 _
0.990 YES 29.0 1.299 MAYBE
10 YES -21.6 YES 41.0
1.100 1.280 MAYBE
11 YC5 0.0 _
1.100 _ YES 40.0 1.280 MAYBE
12 YES
13 52.0
70.0 1.150 YES 10.0
1.220 20.0 1.124
1.195
MAYBE"
14 NO 88.5 1.360 MAYBL 10.0 1.124 MAYBE"
15 NO 112.7 1.380 MAYBE No cut` 1.380 MAYBE
16 NO N/A N/A 'liA?RE N/A N/A MAYBE
17 NO N/A N/A NO N/A N/A NO
18 NO N/A N/A NO N/A N/A NO
19 NO N/A N/A NO N/A N/A NO
20 NO N/A N/A NO N/A N/A NO
N/A: Not analyzed
"-Same factor of safety as "no bench" analysis
"-Based on engineering judgment
Criteria
FS<1.2 Requires stabilization
1.2<FS<1.3 Marginal
1.3<FS<1.5 Monitoring with provision for stabilization
FS>1.5 No stabilization required