An underground mine, in its early stages, requires a carefully planned network of shafts, drifts and raises which serves the following purposes:-
1. Enables one to know the quality of mineral and extent as well as shape, thickness and dip of orebody, nature f country rock, strength or ore and wall rocks, nature and extent of overburden, etc.
2. Permits prospecting to be carried out from underground workings, etc.
3. Provides access and transport facilities for men, material and excavated mineral.
4. Permits arrangement for drainage of water and ventilation of mines.
5. Enables mine planners to decide upon method of stoping.
The formation of such network of shafts, drifts and raises mentioned above is known as development of the mine. The site of sinking the shaft are then decided by the mine owner and the work of sinking of shafts, whether inclined or vertical, is usually entrusted to an established firm of shaft sinking contractors and rarely done departmentally by the mining company. The shaft sinking is a costly process and takes 2-3 years depending on the depth, nature of strata to pass through, and the difficulties one may encounter during sinking. The period of shaft sinking normally utilized by the Mine Executive to procure equipment for underground development, other constructions on the surface and for building up the infrastructure for the mining project. Blasting by Raydet Vis-a-Vis Detonating Cord, Down the Hole Production Drilling Pattern, KHETRI AND KOLIHAN MINES, KHETRI COPPER COMPLEX, Long Hole Drilling 57 mm Diameter hole, MALANJKHAND COPPER PROJECT, Mine Planning and Equipment Selection, Open Cast and Under Ground Mine section Over Hand stoping - Room and Pillar, stope drilling and cable bolting, Sub Level Caving Method (block caving).
