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2004 Geologic Hazard Field Observations <br />South of Divide Mining Area <br /> <br />8.0 GEOLOGIC AND TOPOGRAPHIC OBSERVATIONS IN THE SOUTH OF <br />DMDE MINING AREA <br />Only two observations were made in the field (Field Locations 1 and 2). The rem is n?ng <br />observations were made in the office using stereo pairs of aerial photographs, The USGS high- <br />altitude black and white photos (scale approximately 1 inch = 3,000 feet), taken July 28, 1963, <br />were used as a baseline to define rockfall and landslide conditions during that earlier time period <br />(forty-one years ago). The West Elk color aerial photographs dated July 2, 2004 were then used <br />to update any changes in particular landslide and rockfall areas. <br />8.1 Field Location 1 <br />Field Location 1 was positioned at the spillway on the south side of the dam impounding <br />Minnesota Reservoir and observed on July 15, 2004. The location also was used as a reference <br />point for mapping and evaluation of the major landslide located south of the point (Map 1) and <br />. also rockfall areas near the reservoir. The field observations will be discussed first, followed by <br />observations about the landslide based on stereographic analyses from the black and white and <br />color photographs. <br />8.1.1 Field Observations <br />The reservoir water level was about 3 feet below the bottom of the spillway (Figure 1). This <br />level is higher titan the author recalls in the six annual field observations (1999 to 2004 <br />inclusive). <br /> <br />831-032.621 Wright Water Engineers, Ina Page 19 <br />November 2004 <br />