Since underground mines cannot be seen, utilizing the existing underground maps is the only practical way of mapping them. These maps are the foundation of the Underground Mine Mapping Project.
Underground mine maps were obtained from government agencies, mining companies, and private fee representatives. Contributing entities included Minnesota Department of Natural Resources Division of Lands and Minerals (MNDNR), Iron Range Research Center (IRRC), Minnesota Department of Revenue Minerals Tax Office, the St. Louis County Inspector of Mines, Hibbing Taconite Company, U.S. Steel Keewatin Taconite, U.S. Steel Minntac, United Taconite, Cliffs Natural Resources, Arcelor Mittal, Eveleth Fee Office, Great Northern Iron Ore Properties, Meriden Engineering, RGGS, Department of Interior Office of Surface Mining, and the public.
Over 3000 mine maps were scanned using the Hewlett-Packard designjet copier cc800ps and the designjet 820mfp copier/scanner. The scanners were set with parameters that would give the best resulting scan and minimize the file size for each map. Scans were done with a minimum of 200dpi and a maximum of 600dpi. Black and white scans were done when possible. Color scans were generally converted to grayscale with Adobe Photoshop to reduce file size. Final scanned images (TIF's and JPEG's) were combined by mine and converted to Adobe PDF format with the original image name as a bookmark. The PDF files were then down sampled to as much as 50dpi for use on the internet. The higher resolution PDF files are available from the DNR Division of Lands and Minerals, 1525 3rd Ave East, Hibbing, MN 55746 218-231-8484.
The Minnesota Department of Natural Resources makes no representation or warranties, express or implied, with respect to the reuse of data provided herewith, regardless of its format or the means of its transmission. There is no guarantee or representation to the user as to the accuracy, currency, suitability, or reliability of this data for any purpose. The user accepts the data 'as is', and assumes all risks associated with its use. By accepting this data, the user agrees not to transmit this data or provide access to it or any part of it to another party unless the user shall include with the data a copy of this disclaimer. The Minnesota Department of Natural Resources assumes no responsibility for actual or consequential damage incurred as a result of any user's reliance on this data.