Extent of available data.
This data layer identifies the underground mine workings within the Mesabi Range. It was developed by the Minnesota Department of Natural Resources and is comprised of detailed information on documented underground mine workings (shafts, drifts, mined extents, more) on the Mesabi Range. This information can be used for mapping, documentation, potential energy storage exploration (pumped hydro, compressed air), monitoring, analysis, and land use planning purposes. It generates a surface reflection of the extent of underground workings, and hence, areas of potential subsidence and/or underground void space. Note that due to incomplete/non-existent/unfound maps, the mined extents may exceed what is shown.