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Subsidence Field Observations <br />West Elk Mine <br />July 22-24, 2003 <br />5. No positively identifiable subsidence cracks were observed on the south ridge azea of <br />West Flatiron in either the sandstones of the Ohio Creek Member of the Mesaverde <br />Formation or the overlying clays and silts of the Wasatch Formation. <br />6. The debris flows (landslides) located on the southwest flank of West Flatiron above <br />mined-out longwall Panels 14 and 15 show no evidence of being affected by mining in <br />longwall Panels 14 and 15. In addition, no effect was observed on the large landslide on <br />the west side of Deep Creek from mining in the eastern part of longwall Pane] 17. <br />7. The condition of the subsidence cracks that were first observed above the west end of <br />mined-out longwall Panel 14 on August 28, 2002, is a function of the material in which <br />the crack occurs. The cracks in the durable sandstone and siltstone look much like they <br />did in 2002. However, the cracks that occurred in colluvium and soil are healing and <br />sealing significantly, and aze much less evident than they were last year. Some of these <br />cracks aze no longer visible. <br />8. The landslides on the north side of Minnesota Reservoir are similaz to their appearance in <br />August 2002. They are as stable as last year due to the dry conditions that existed both <br />yeazs. The landslides are remote from the areas of influence of any coal mining. <br />831-032.610 Wright Water Engineers, Inc. Page 2 <br />' September 2003 <br />