Creation of underground chambers by blasting in rocksalt and associated problems

Abstract

Blasting for creation of underground chambers or to extract water soluble minerals like halite, carnelite, kieserite and anhydrite, etc., generally create lot of environmental, economic and strata control problems. Therefore it requires very careful and cautious design so that technical problems could be minimised with least cost. Formation of leached zone is one of the most complex and serious problems which results in weakening of the roof posing strata control and environmental hazards. This problem is discussed in detail in this paper with particular reference to rocksalt deposits and a number of suggestions have been made. These can also be applied to blasting in other water soluble mineral deposits.