JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B. Tech III SURFACE MINING TECHNOLOGY Previous Question Paper (February - 2023 - R16)

The stripping ratio is the primary economic indicator in surface mining, defined as the volume of overburden that must be removed to extract a unit volume or weight of ore. Its significance lies in determining the economic viability of a mining project, as it dictates the cost-to-benefit ratio; when the stripping ratio exceeds the break-even stripping ratio, the mining operation becomes unprofitable, serving as the critical threshold for deciding between open-pit and underground mining methods.

Mine life refers to the total duration of time during which a mining operation remains economically and operationally viable. It is defined as the period from the commencement of commercial production until the depletion of the extractable mineral reserves or the point at which the cost of extraction exceeds the market value of the commodity.

The life of a mine is calculated using the formula:

This duration is a critical parameter for mine planning, as it dictates the depreciation schedule of capital assets, the design of infrastructure, and the long-term feasibility of the project.