Abandoned Mine Digitization

Abandoned Mine Digitization- Converting Historic Mine Drawings into GIS for Safety and Subsidence

Colorado Department of Natural Resources Colorado Geological Survey The Colorado Geological Survey (CGS) has been involved in characterizing and understanding various aspects of abandoned mine lands in Colorado.  Across the state, there are an estimated 23,000 abandoned mine sites on both public and private land.  These abandoned mines have a legacy of hazards ranging from environmental issues like water quality degradation and increased sedimentation, to physical hazards associated with the mines themselves.
Colorado State Engineers needed a method to assist in locating and mitigating areas of mine subsidence throughout Colorado.  Subsidence is the movement of the earth's surface caused by the collapse of underground mine tunnels or shafts.  The location of these mines and their related underground workings existed only in paper format, filed away in a storage room. The purpose of the project was to convert these hard-copy documents into a mapping system (GIS), so that the approximate location of the mines would be readily available and analyzed with current aerial photography, land planning, and land use maps.	The Morley Mine with Original Map in ESRI ArcMap The Morley Mine Overlaid on Aerial Photography in ESRI ArcMap
The data source provided by CGS included 930 original surveyed hard-copy maps on mylar, paper, and linen.  GPS surveyed points of the mine entrances were also supplied as additional control for the registration of these maps into their proper geospatial location.
Individual maps and plates were scanned and georeferenced using aerial photography, public land survey grid, and GPS points as control. Over 25 different mine features were digitized and attributed according to CGS specifications including adits, boreholes, cross sections, faults,  isopachs, limits of mining, mine outlines, prf stability, shafts, sinkholes, slope, subsidence inventory, subsidence profiles, surface traces, workings, and other miscellaneous features. Final deliverables were a series of shapefiles and ESRI personal geodatabases. All delivered data was provided with extensive metadata.	Analysis of Historic  Information Scanning and Georeferencing of Historic Maps GIS Conversion and Attribution
This data would be used by miners, geologists, contractors and other entities to safely plan and route around these abandoned mine shafts. The GIS data also allows for a more focused and effective response to disaster should a collapse occur.