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

* * * * * SIMPLIFIED JANBU METHOD * * * * *
The 10 most critical of all the failure surfaces examined
are displayed below - the most critical first
Failure surface No. 1 specified by 5 coordinate points
Point x-surf y-surf
No. (ft) (ft)'
1 449.49 6883.68
2 403.86 6904.13 r
3 364.96 6935.54
4 334.40 6975.12
5 332.61 6980.00
** Corrected JANBU FOS = 1.000 ** (Fo factor = 1.040)
Failure surface No. 2 specified by 4 coordinate points
Point x-surf y-surf
No. (ft) (ft)
1 445.90 6886.07
2 400.75 6907.55
3 362.20 6939.40
4 334.55 6980.00
** Corrected JANBU FOS = 1.001 ** (FO factor = 1.040)
Failure surface No. 3 specified by 4 coordinate points
Point x-surf y-surf
No. (ft) (ft)
1 435.13 6893.25
2 389.83 6914.42
3 353.71 6949.00
4 330.78 6980.00
** Corrected JANBU FOS = 1.002 ** (Fo factor = 1.041)
Failure surface No. 4 specified by 4 coordinate points
Point x-surf y-surf
No. (ft) (ft)
1 431.54 6895.64
2 386.50 6917.36
3 351.21 6952.78
4 328.44 6980.69
** Corrected JANBU FOS = 1.010 ** (FO factor = 1.039)