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'" 10;' development in areas of active mud floods, snow avalanches, or land- slide masses will be essentially the same whether the development takes place today or 50 years in the future. It is our hope that the data of this report will contribute toward feasible development and sound land use practices for the entire Marble area. Area East of Carbonate Creek on Slopes of Mt.' Daly (1) General Slope Stability The 'entire area east of Carbonate Creek and north 'of Beaver Lake consists of steep to moderately steep slopes underlain by northwest- dipping Mancos Shale. The surface is mantled by residual,and colluvial soils, landslide deposits, and glacial debris - all of highly variable thickness. Several small and medium sized active landslides are present along Carbonate Creek. These appear to have been caused by oversteepening of slopes by erosion as the channel of Carbonate Creek has rapidly en- trenched itself across the area. The active or recently active land- slides are designated la, lb, and Ie. Two other much larger slide masses, designated ld, and Ie, do not appear to be active at the present time. The larger landslides are not directly related to stream erosion as are most of the others. These active and ancient slide masses indicate the marginal sta- 'bility of, slopes on this part of Mt. Daly. Any redistribution of stresses by excavation, increased erosion, placement of fill material or struc- tures, or surface drainage changes, carries the risk of initiating new slides or reactivating old ones.' These critical geologic and soil engi- neering factors must be recognized and taken into account in any develop- ment,activity. Numerous seeps and slough areas aggravate the general "