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Fall 2008 Subsidence and Geologic Field Observations <br />Box Canyon, Apache Rocks, and South of Divide Mining Areas <br />No changes have been observed in this slide since 2005. except the landslide scar and associated <br />slide rocks appear more Nveathered (compare Figure 4' with Figure page 12 ofthe 2005 report <br />and Figure 30, page 38 of the 2006 report). <br />Ll <br />• <br />Figure 43. Fall 2008 southeastward view of the landslide located east of the mouth of Box <br />Canyon. The slide, which is located in the zone of construction influence of Highway 133, consists <br />of an upper headscarp, a lower slumped area, and a still lower debris flow. The lower part of the <br />slide moved the highway alignment northward (to the left) and also raised it in the left middle <br />ground. <br />5.18.2 Landslide Located West of the Mouth of Box Canyon <br />This landslide initially occurred during a period of high precipitation in the mud 1980s and not as <br />a result of alining activities. It occurred within a IcNv \cars after construction off Ii Ilxk,a\, 1-133 <br />the south side of the North Fork before mining occurred in the area (Figure 44). In contrast to the <br />landslide east of the mouth of l3ox Canyon. multiple movements have occurred oil tills landslide <br />during periods of high precipitation in the mid 1980s and nlld I990s. No movement has been <br />observed ofthis landslide area since July 2005 (compare Figure 44 with Figure 32. page 40 ofthe <br />2006 report). <br />831-032.790 Wright Water Engineers, Inc. Page 57 <br />December 2008