PERMFILE44895

• Permit No: C1980007
• IBM Index Class Name: Permit File
• Doc Date: 6/2/2006
• Doc Name: for the West Flatiron Lease Area
• Section_Exhibit Name: Exhibit 60C Subsidence Eval & 2004 Geologic Hazard Field Obsersvations
• Media Type: D
• Archive: No

•
E#ribit 80C
Subsidence Evaluation and 2004 Geologic Hazard Field Observations
West Flatiron Lease Ala
7.1.2 Maximum Tilt
Lonttwall Pane118A:
• Maximum tilt (Mm) above the longwall panel centerline is projected to range from 0.011 to
0.048 (0.1 to 4.8 percent).
Lonawall Panels 18 and 19:
• Maximum tilt (Mm) above the longwall panel centers is projected to range from 0.005 to
0.039 (0.5 to 3.9 percent).
lontzwall Panels 20 and 21:
• Maximum tilt (Mm) above the longwall panel centers is estimated to range from 0.005 to
0.027 (0.50 to 2.7 percent).
7.1.3 Maximum Horizontal Strain
The horizontal stain values, listed below for longwall panels 18A through 21, fit within the range
of horizontal tensile strains determined in four different mining areas of the Western United
States studied by the author (0.45 to 3 (Sm/d). The curves projected for tensile and compressive
strain for the West Flatiron Lease area are based on the West Elk Monitoring Network and the
National Coal Board of the United Kingdom (Figure 1).
Longwall Pane118A:
• Maximtmt tensile (positive) horiwntal strain is projected to range from 0.006 to 0.024 (0.6 to
2.4 percent).
•
• Maximum compressive (negative) horizontal strain is estimated to vary from -0.006 to -0.038
(-0.6 to -3.8 percent).
831-032.650 Wright Water Engineers, Inc Page 14
November 2004