What Does Strip Mining Mean?
Strip mining is a mineral-extraction process in which a layer or seam of undesired material (called “overburden”) is removed from the surface of an area to allow efficient access to a desired material existing underneath the layer being stripped. As the process suggests, it is a form of surface mining, and it is primarily used to extract material that lays relatively close to the surface.
There are two types of strip-mining approaches. The first and most common approach is referred to as area mining; it is used on fairly flat terrain and involves the removal of long strips (potentially hundreds of meters) at once. In this approach, the overburden removed from each new strip is deposited into the excavated area left by the previous strip. The second approach, called contour mining, is used on hilly terrain and involves stripping land in a manner that mirrors its topography.
Safeopedia Explains Strip Mining
Strip-mining processes are subject to a variety of occupational and environmental health and safety regulations in any advanced country in which the activity is practiced. Because mining is recognized as a particularly hazardous occupation with a number of practice-specific safety hazards, these regulations may be enforced by an industry-specific oversight body. For instance, in the United States, the Mine Safety and Health Administration (MSHA), not OSHA, is responsible for enforcing regulations related to mine safety.
Typical strip-mining hazards include equipment-related ergonomic hazards (e.g. hand-arm vibration hazards), exposure to harmful dusts and particulates created during the mining activity, and risks associated with the use of mining equipment. In the U.S., the fatality rate at surface mines between 2006 and 2015 ranged between seven and 16 deaths per 100,000 full-time employees. The most-common causes of death were the use of equipment, slips and falls, and being struck by falling rock or similar material. The lost-time injury rate over the same period ranged from 1.4 to 2.1 injuries per 100 full-time employees. It should be noted that not all forms of surface mining are equally hazardous. For example, stone mining carries a consistently higher rate of nonfatal injury in the U.S. than mining of other commodities does.
According to statistics presented to the MSHA, the injury and fatality rates faced by strip miners are generally lower than those faced by underground miners. However, the absolute number of injuries and fatalities across all surface-mining activities is higher than the total number across underground mining activities, as the vast majority of hours spent conducting mining activity is spent working on surface mines (86, 2008).