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

INTRODUCTION
The mining of the 2nd and 3rd East Sections of the Roadside Mine of GEX
Colorado, Inc. will exirad coal from beneath and adjacent to Ute Water Co's. surface
facilities. Sufficiently large pillars must be left to assure that these facilities will
not be damaged by This mining.
~ The method of analysis involved, first, evaluating the strength of pillars in
Section "G" which were previously mined by the "Pillar Slabbing" method planned for
the 2nd and 3rd East Sections. Various potential pillar sizes were then evaluated to
estimate their safety foctors for their application to the 2nd and 3rd East Sectioru
of the Roadside Mine. Finally, the potential maximum subsidence effects resulting
from "worst case" pillar failure were predicted for failure of various pillar sizes in
the 2nd and 3rd East Sections.
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