|Solution mining has resulted in land subsidence in and around the city of Hutchinson.|
|Relation of roof rock failure to method of salt mining (after Walters, 1978)|
|Mining Method||Portion of Salt Removed||Associated Surface Subsidence|
|Underground Mines||One bed 8' to 15' thick in lower salt;
room and pillar with 75% of salt removed.
|Predominantly the uppermost salt decreasing downward.||Known surface subsidences
in 1914, 1925, 1952, 1974
|Predominantly the lowermost salt decreasing upward.
Void space is a narrow corridor.
|Solution Mining for storage
of Liquefied Petroleum Gas
|Lower salt below "shale" marker;
100' +/- vertically, 40' +/- diameter.
|Hutchinson, Kansas: Land Subsidence Areas (after Walters, 1978)|
|1914||Morton Salt Company||Southwest of city||Rapid surface cratering|
|1925||Carey Salt Company||Downtown||Slow subsidence of only a few inches|
|1952||Barton Salt Company||Southeast of city, north of plant||Ground subsidence with water coming in the hole|
|1974||Cargill (formerly Barton)||Southeast of city, south of plant||300 ft diameter crater, volume calculated
to be 90,000 cubic yards (see photos below)
Photographs of Cargill Sinkhole-1974 (from Walters, 1978)
Cargill Sinkhole, October 21, 1974
Cargill Sinkhole Stabilized, November 12, 1974
Cargill Plant Layout, Showing North and South Sinkholes and other Features (after Walters, 1978)
Cross Section Through South Sinkhole, Cargill Site (from Walters, 1978)
Info from the U.S. Geological Survey--Land Subsidence related to Groundwater Withdrawal:
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