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2004 Geologic Hazard Field Observations <br />South of Divide Mining Area <br />• Overburden depth on the slide azea to the E Seam ranges from 0 to about 425 feet. The base <br />of the slide is a few hundred below the E Seam. <br />• Aerial photo analyses of the features in stereographic projection shows that the landslide <br />consists of three major features (Figure 9): <br />1. A slumped area in the upper part located below a steep head scarp with a slight backward <br />rotation. <br />2. A lower run-out zone consisting of composite debris flows, some of which show <br />movement since 1963. <br />3. Recent (post 1963) movement in the upper, northeastern comer of the slide and also <br />approximately midway in the slide above, and along, Lion Gulch. <br />• The rockfall potential ranges from moderate to high in the cliffs, ledges, and steep slopes <br />located northwazd and southward from the landslide azea. The highest cliffs and steepest <br />• slopes, however, occur below the stratigraphic position of the E Seam. Mining, therefore, <br />would not affect the natural rockfall process. <br />• <br />831-032.621 Wright Water Engineers, Inc. Page 30 <br />November2004 <br />