REV04523

• Permit No: C1980007
• IBM Index Class Name: Revision
• Doc Date: 11/21/1996
• Doc Name: SYLVESTER GULCH STABILITY ANALYSIS FOR RECLAMATION
• From: GOLDER ASSOCIATES
• To: MOUNTAIN COAL CO
• Type & Sequence: PR7
• Media Type: D
• Archive: No

Factors of safety have been calculated by the
* * * * * SIMPLIFIED BISHOP METHOD * * * *
The most critical circular failure surface
is specified by 22 coordinate points
Point x-surf y-surf
No. (ft) (ft)
1 650.00 7076.00
2 629.49 7080.50
3 609.11 7085.58
4 588.89 7091.23
5 568.83 7097.45
6 548.95 7104.23
7 529.28 7111.57
S 509.81 7119.45
9 490.58 7127.89
10 471.59 7136.85
11 452.86 7146.35
12 434.41 7156.38
13 416.25 7166.92
14 398.39 7177.96
15 380.84 7189.51
16 363.63 7201.54
17 346.77 7214.05
18 330.26 7227.03
19 314.12 7240.47
20 298.37 7254.36
21 283.02 7268.69
22 279.08 7272.58
**** Simplified BISHOP FOS = 1.493 ****
r'
The following is a summary of the TEN most critical surfaces
Problem Description SYLVESTER GULCH-Water Tank Rd Sec EE
FOS Circle Center Radius Initial Terminal Resisting
(BISHOP) x-coord y-coord x-coord x-coord Moment
(ft) (ft) (f t) (ft) (ft) (ft-lb)
1. 1.493 799.70 7806.70 745.88 650.00 279.08 6.437E+OS
2. 1.504 735.67 7715.23 634.29 625.92 282.35 4.938E+08
3. 1.506 716.28 7606.70 533.11 647.44 307.23 4.438E+OB
4. 1.507 707.38 7666.84 576.78 614.10 289.10 4.037E+08
5. 1.507 769.97 7787.16 710.45 624.36 280.76 4.997E+08
6. 1.508 727.93 7716.32 633.06 624.36 275.45 5.212E+08