PERMFILE131380

• Permit No: C1981041A
• IBM Index Class Name: Permit File
• Doc Date: 6/16/2003
• Doc Name: TOC to Appendix 20-3
• Section_Exhibit Name: Tab 20 Subsidence Survey Monitoring & Control Plan
• Media Type: D
• Archive: Yes

-14-
•

~.:
i~
~.
r
i_
r
i
TABLE 5, Percent increase in Panel G factor of safety for various
retreat pillar sizes under Ute Water Co, surface
facilities.
3rd East Physical Properties (~ = 48.8°; 0'b = 782 psi) for Retreat
Pillars and 2nd East Physical Properties (~ = 45.5°; a-o = 785 psi)
for Panel G 16 x 100-ft Retreat Pillars.*
Depth Retreat Pillar Sizes (ft}
ft 12 x 80 14 x 80 16 x 80 18 x 80 20 x 80
200 +28.5X +50.6X +72,gX +94.9X +117.1X
250 +18.4X +39.2X +59.5X +79.7X +100.6X
300 +12.0X +31.OX +50.6X +70.3X +89.9X
ALL Coal Physical Properties (m = 47.20; d'"o 783 psi)**
r
I
f"~
L
~.
L
f"
200 +12.9X +32.4X +S1.8X +71.2X +90.6X
250 +3.5X +21.8X +39.4X +57.6X +75.9X
300 -2.45 +14.1X +31.2X +48.2X +65.3X
*Most probable values.
**Conservative values.
Underlined values are for recortmended pillar sizes at specified depths.
•