65 YEARS OF COAL MINED OUT AREAS IN ILLINOIS - EVOLUTION OF COAL MINED OUT AREA MAPS AT THE ILLINOIS STATE GEOLOGICAL SURVEY (ISGS)

There are approximately 7,400 coal mines in Illinois spread over 76 counties, totaling in areal extent and impacting close to 1,000,000 acres. Mined out areas (MOA) potentially impact industry, housing, roads, railroads, schools, infrastructure and development. The ISGS has created mined out area maps for use by the public, industry and government for 65 years. Over time both the locational accuracy and degree of recorded detail have increased and additional historical cross-checking has been incorporated. Initial MOA maps in the 1920s were not mapped areas at all, but rather mines were shown as point locations. Later incarnations in the 1950s were hand drawn, relatively incomplete and offered little in the way of documentation. It took until 1969 for a first official, but error-filled, MOA publication to be released. The first digital mapping efforts involving digitizing mine outlines occurred in 1981. Errors introduced in the 1969 maps were corrected at this time. Notably, little in the way of systematic documentation (necessary for accurate cross checking of mined extent), or the recording of coal production and geologic and stratigraphic details, had been incorporated at this point. The first documentation efforts finally occurred in 1984, but were incomplete and of limited usefulness.

Our current coal MOA mapping effort began in 1999, and represents a thorough and definitive research and discovery of all known coal mine maps and correlated historical information. Mined out area maps and histories with the greatest amount of detail are being compiled and organized onto topographic quadrangle bases (1:24,000) with an associated information directory. A more simplified version is compiled for use at county map scale (1:100,000). In an effort to reach as many people as possible and best communicate our mapping efforts to the public, industry, and government, an online interactive mapping service called ILMINES has been created on the ISGS website. ILMINES represents the next generation of coal mine information dispersal, with a familiar Google Maps-style interface for rapid searching, and links to the quadrangle and county scale maps, for more thorough inquires. In the future we plan to incorporate additional mine-specific information such as mine notes, original company mine maps, and other relevant information.