Mining engineering is an engineering discipline that involves the practice, the theory, the science, the technology, and application of extracting and processing minerals from a naturally occurring environment. Mining engineering also includes processing minerals for additional value. Mining engineering includes facets of geological, civil, mechanical and materials engineering. Mining engineers conduct initial surveys of the deposits in a potential area for mining to determine the economic and environmental benefits and costs of starting an operation. They prepare operations and estimate the cost and duration of a project. They then decide how to safely and efficiently extract goods from viable mines. Mining engineers are involved in every step of development, from determining the best method of drilling and blasting to starting a mine and then creating the shafts, ventilation systems, mine services, haulage mechanisms and other supporting structures to allow miners to work safely.