125. 



year and 15 cubic feet of salt per ton, the space mined out would be 

 414 acre-feet. With a thickness of salt of 10 feet and 60% recovery, 

 about 68 acres would be mined out annually. The total production of 

 the mine has not been published, but, with 30 years of operation, it 

 is probably not less than 1500 acres. 



At Portland Point, on the east side of Cayuga Lake, Tompkins County, 

 a mine has been operated for about 20 years. Details of production, 

 etc. are not known. 



Several other rock-salt mines were formerly operated in New York 

 but have been closed down. The oldest mine was at Livonia, Livingston 

 County, and was operated from 1883 to 1890. It was 1430 feet in depth. 

 The mine is now filled with water and the condition of the shaft is now 

 known. About 50 acres was mined out. Another mine at Lehigh, 

 Genessee County, had a depth of 825 feet and was operated about 4 

 years. The quantity mined was about 15 acre-feet. The shaft is filled 

 with -water to the surface. 



5.3 The mine of the International Salt Company, at Detroit, is the only 

 producer of rock salt in Michigan . (1 ' ) It is operated through two shafts 

 about 1100 feet deep and the uppermost bed of the Salina formation is 

 worked. It varies in thickness throughout the mine from about 19' to 

 40'. The greatest thickness mined is about 36', 4' being left for roof. 

 About 60% of the area is mined, the remainder being left for pillars. 

 The rooms are limited to a width of 60'. About 700 acres has been 

 mined out. The mine is dry, except for an occasional seeping of a few 

 cubic feet of bittern from the formation. The mine has been in opera - 

 tion since 1910 and, during that period, only one small roof-fall has 

 occurred. The shaft is located about 11/2 miles from the Detroit 

 River and about 1/4 mile from the River Rouge. The surface above the 

 mine is chiefly property of the Pennsylvanian and Wabash railroads used 

 for yards and shops. About 20' below the bottom of the bed now mined 

 and separated from it by a bed of dolomitic limestone, is a second bed 

 of salt, much thicker than the one being worked. The top of this lower 

 bed is exposed in one of the mine workings. 



5 .4 In Kansas, three rock salt mines are now operated. ( °> The Carey 

 Salt Company operates a mine near Hutchison through a shaft 645' deep. 

 The bed mined has a thickness of 10'. The total volume mined out is 

 about 145 acre-feet, equivalent to about 14 acres. At Kanopolis, the 

 Independent Salt Company has two shafts 846' deep and is mining a bed 

 15-16' thick. The total mined-out space is about 4,000 acre-feet, 

 equivalent to about 25 acres. The American Salt Corporation has a 



