Let's take a look at the Mining Life Cycle.

Ever wonder how mining operations work? A typical project goes through a series of different phases which we refer to as the mining life cycle, each presenting unique challenges and opportunities. Click on the categories below for a description of each phase.

life of mine timeline

mining life cycle exploration

In Michigan, all metallic mineral exploration and development activities on state and private property are regulated by the DEQ, including leasing and drilling. A metallic mineral lease within itself does not give a company permission to mine. If a deposit is found, separate applications and approvals will be required before mining activity can take place.

It can take years or even decades to discover a viable deposit. Geologists utilize aerial surveys, soil analysis, and drilling to determine if there is a sufficient mineral deposit to justify mining. Many factors control the economic viability of a deposit, but the most important are the grade, size, location, and demand. Exploration does mean a mine is going to be developed.

mining life cycle designDetailed studies (e.g., feasibility study) are conducted to determine the capital requirements, community context, permitting requirements, critical environmental challenges, and other information vital in moving the project to the next step. If the outcomes yield positive results, additional research and planning will take place at a more granular level. As more information is gathered, companies gain a far greater understanding of mine plans, facility layouts, infrastructure, and environmental and social impact assessments.

mining life cycle permittingAll nonferrous metallic mines in Michigan are required to submit the necessary permit applications with the DEQ Office of Oil, Gas, and Minerals. The permits typically include mine, water discharge, and air. Government agencies thoroughly review each permit application and gather public input before issuing a permit. Each permit comes with conditions that must be met before, during, and after mining occurs. While these permits are a requirement for all mines, the exact details and specifications are unique for each project.

mining life cycle constructionUpon receipt of permit approvals and capital investment, the project can prepare for development. Hundreds of workers will build the infrastructure required to support the operation. Examples include roads, water treatment plants, maintenance facilities, warehouses, contact water basins, and process plants. Construction of such sites is a massive undertaking and boost to the local economy. A typical project can take 15 to 20 years between discovery and construction. See what the Back Forty Mine will look post-construction here.

mining life cycle production

Mining involves extracting large amounts of rock from below the Earth’s surface. The goal is to separate the valuable minerals from the non-economical rock.

To do this, overlying rock is blasted, and the material is placed in a truck and hauled to the surface. The material that contains valuable minerals (e.g., ore) is sent to the process plant, while the non-economical material (e.g., waste rock) is taken to the temporary waste rock facility. The waste rock will be used to backfill the pit once mining ends.

In the process plant (e.g., mill) the zinc/copper/lead ore goes through a conventional process of crushing, grinding, and floatation to separate the minerals. The gold/silver ore needs a few more additional steps before the valuable minerals are captured.

mining life cycle reclamation-postclosureWhen mining ceases, the site is reclaimed, and land is returned to a state compatible with adjacent properties. Examples of reclamation activities include removal of all buildings and infrastructure, capping and vegetating the tailings facility, backfilling the mine with waste rock. Postclosure monitoring lasts for 20 years following completion and approval of reclamation. The time may be shorter if the DEQ determines monitoring and maintenance activities to preserve the integrity of the area are complete. The DEQ requires an annual mining and reclamation report filed each year with the agency. The reports are available to the public.