Longwall mining and potash

CIM Bulletin, Vol. 79, No. 887, 1986

G. HERGET, Project Leader, Potash Mining, Rock Mechanics Laboratory, CANMET/EMR, Ottawa, Ontario

A brief visit to European longwall mining operations in potash showed that retreating longwall mining provides a very attractive alternative to room-and-pillar mining, especially in areas with bad roof, narrow seams and areas with high ground pressures. Mines de Potasse d'Alsace, France converted all potash operations to longwall mining in 1980. Recovery rates per panel vary between 75% to 85% which compares very favourably with Saskatchewan values. Ground pressure in Saskatchewan are comparable to those of some of the deposits in Europe, but the presence of water in the hanging wall of Saskatchewan orebodies has to be given serious consideration. However, given the mining experience in Saskatchewan and the improved technology for laboratory and field investigations, a review of present mining practice in Saskatchewan is desirable.

Keywords: Potash, Potash mining, Longwall mining, Rock mechanics, Spain, France, U.S.S.R