Computer Terrain Mapping, Inc. 2005 map The Alpine Loop Geologic Hazards data set shows the geologic hazards on lands along the Loop. This data set is one of the development constraints used to determine Development Potential. Hazard data was relatively complete for San Juan County and the portion of San Miguel County that falls in the study area. Hazard mapping from the Colorado Geological Survey covered the area around the Town of Ouray. The only hazard data uncovered for Hinsdale County was the portion of the Slumgullion Slide within the study area. The Alpine Loop Spatial Analysis and Mapping Project inventoried natural and cultural resources and identified important areas where overlapping resources occur. The results from this project will provide an opportunity for area stakeholders - landowners, outdoor enthusiasts, surrounding communities, federal government agencies and local and national preservation groups - to come together to find solutions that maintain the Alpine Loop experience for future visitors and residents, while working within the framework of landowner objectives as well as local and federal government goals. The Alpine Loop Spatial Analysis and Mapping Project analyzed the Alpine Loop landscape, considering important natural and cultural resources along with the likelihood of development based upon building constraints. The Project aims to provide a planning tool for area stakeholders as they consider the variety of land management options and the future of this magnificent region. The next logical step will be to craft solutions that work within the framework of landowner desires, local and federal government land management goals, and available financial and technical resources to manage the area in a way that preserves the Alpine Loop experience for future generations. While the Alpine Loop lies within three counties - San Juan, Hinsdale and Ouray - the analytical work extended into a portion of San Miguel County. The resulting mapping and analyses will: 1. Create a spatial foundation to aid future projects in the Alpine Loop corridor; 2. Serve as a prioritization tool for evaluating the conservation potential of individual private parcels; 3. Provide the necessary framework for pursuing future funding opportunities. 2003 2005 Data were retrieved from various sources and analyzed between 2003 and 2005. See Data Quality Information for time information for source data. Complete None Planned -107.8725478 -107.2256611 38.08819806 37.73515861 None Conservation Development Geohazard None United States North America Colorado San Juan Mountains Ouray County San Juan County Hinsdale County San Miguel County Ouray Silverton Lake City None None. Computer Terrain Mapping, Inc. Ed Russell President mailing

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Boulder CO 80306 USA 303.444.1670 303.443.4856 ctm@ctmap.com 8:00-5:00 MT This data set is the product of a collaborative process between numerous agencies, organizations and interested individuals from the beautiful Alpine Loop region. GRASS version 5 on Red-Hat Linux version 8.0 exported to an ASCII Grid Determined from a variety of data sources of unknown accuracy. Data are calculated from a variety of data sources of unknown accuracy. Only basic spot checking based on knowledge of terrain was performed. Coverage was nearly complete for San Juan County and San Miguel County. The area around Ouray had geohazard mapping. Only the Slumgullion Slide within Hinsdale County was used. San Miguel County GIS Department 2002 map Telluride, Colorado San Miguel County GIS Department San Miguel County Geohazard including rockfall, landslide, colluvial slopes, and subsidence. digital data 20021125 file date San Miguel County Geohazards Geologic hazards for San Miguel County Colorado. Candace L. Jochim, Colorado Geological Survey 1986 map Denver, Colorado Colorado Geological Survey; Department of Natural Resources; State of Colorado Special Publication 30. Map of geologic hazards near the city of Ouray Colorado. Map indicates areas of very high, high, and moderate-to-low hazard. Base from USGS 7-1/2 minute quadrangle. Paper Map and Book 1986 publication date City of Ouray Geologic Geologic hazards for City of Ouray Colorado. William A. Gallant 1976 map Golden, Colorado Charles S. Robinson and Associates, Inc. Approved by San Juan County Commissioners. Paper Maps 1975 1976 publication date San Juan County Geohazards Geologic hazards for San Juan County Philip S. Powers Marta Chiarle 1994 map Unknown USGS Used resulting digital file. digital 1994 publication date Slumgullion Slide Slumgullion Slide in Hinsdale County Classify TS: Talus Slope as 2 (moderate), CSA: Colluvial Slopes (2) Accelerated as 3 (high), RG: Rock Glacier as 3 (high), RF: Rock Fall as 3 (high), CST: Colluvial Slopes (1) Thick as 2 (moderate), SL: Landslide as 3 (high), PF: Floodplain as 2 (moderate), TSS as 3 (high), DF: Debris Fan as 2 (moderate), CSM: Colluvial Slopes (3) Moderate as 2 (moderate), ES: Expansive Soils as 2 (moderate), CSI: Colluvial Slopes (1) Inactive as 1 (low), SW: Subsidence as 3 (high), TAI: Tailings as 3 (high), and SF as 3 (high). San Miguel County Geologic 2004 San Miguel County Geologic Classified Classify Very High Hazard as 3 (high), High Hazard as 2 (moderate), Moderate to Low Hazard as 1 (low), Flood as 1 (low), High Hazard and Flood as 3 (high), Moderate to Low Hazard and Flood as 2 (moderate), Fans as 1 (low), Very High Hazard and Fans as 3 (high), High Hazard and Fans as 3 (high), Moderate to Low Hazard and Fans as 2 (moderate). City of Ouray Geologic 2004 City Ouray Geologic Classified High hazard (3) values were assigned to swamp, bogs and floodplains (mapped as geohazards), rockfall zones, talus slopes, rock glaciers and debris fans. Medium hazard (2) was applied to talus on gentle slopes and stable colluvium or bedrock on steep slopes. Low hazard (1) was assigned to stable gravel terraces and stable thin colluvium or bedrock on gentle or moderate slopes. San Juan County Geohazards 2004 San Juan County Geologic Classified Assign high hazard value to areas within the Slumgullion Slide. Hinsdale County Geohazards 2004 Hinsdale County Geologic Classified Combine sources in a raster format to create low, medium and high hazard values to be applied as a development constraint. San Miguel County Geologic Classified City of Ouray Geologic Classified San Juan County Geologic Classified Hinsdale County Geologic Classified 2004 Raster Grid Cell 1256 1863 Universal Transverse Mercator 13 .9996 -105 00 00 00 00 00 500000 0 coordinate pair 30.0 30.0 METERS North American Datum of 1983 (NAD83) GRS 1980 6378137 298.257222101 Geohazard grid cell Any of the data elements in the geohazard map author geohazard cell value Values of 3 (high hazard), 2 (medium hazard), 1 (low hazard), and 0 (no hazard) author 0 3 Computer Terrain Mapping, Inc. Ed Russell President mailing

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Boulder CO 80306 USA 303.444.1670 303.443.4856 ctm@ctmap.com Alpine Loop Spatial Analysis and Mapping Project Computer Terrain Mapping, Inc. (CTM) provides this data set as is. CTM makes no guarantee or warranty concerning the accuracy of information contained in the data. CTM further makes no warranties, either expressed or implied as to any other matter whatsoever, including, without limitation, the condition of the product, or its fitness for any particular purpose. The burden for determining fitness for use lies entirely with the user. Although this data has been processed successfully on computers at CTM, no warranty, expressed or implied, is made by the CTM regarding the use of this data on any other system, nor does the fact of distribution constitute or imply any such warranty. Contact distributor to receive additional copies. 200504 Computer Terrain Mapping, Inc. Ed Russell President mailing

PO Box 4982

Boulder CO 80306 USA 303.444.1670 303.443.4856 ctm@ctmap.com 8:00-5:00 MT FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998