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Mining and the Environment Questions for Today ► What is ore and what are examples of useful ores extracted from the crust? ► What are the different ways we extract ore? ► How does mining harm the environment? ► What are some laws that regulate mining and reclamation? Nonrenewable mineral resources ► Mineral Resources: A concentration of naturally occurring material from the earth’s crust that can be extracted and processed into useful products. ►Fossil Fuels ►Metallic Minerals ►Nonmetallic Minerals Nonrenewable Mineral Resources ► Ores: A rock that contains a large enough concentration of a particular mineral to be profitable Two types: ►High-Grade ►Low-Grade Valuable Minerals and Ore ► Metallic Minerals Aluminum Steel ► An alloy of Iron with concentrations of Manganese, Cobalt, Molybdenum, and Chromium Copper Platinum Gold ► Nonmetallic Minerals Sand Limestone Phosphate salts Methods of Mineral Removal ► Two types of Methods: Surface Mining ►When gigantic mechanized equipment separate the overburden, rocks and soil covering the ore, from the ore. Subsurface Mining ►When machines and workers mine underground for seams of ore or other nonrenewable resource. Surface Mining ► Four types of Surface Mining: Open-pit mining Strip Mining Contour Mining Mountain-top removal Open Pit Mining ► In Open Pit Mining, machines dig holes and remove ores, sand, gravel, and stone. Strip Mining ► When mineral deposit lie close to earth’s surface, the most economical and useful extraction method is Strip Mining. ► Two Types: Area Strip Mining Contour Strip Mining Strip Mining ► Area Strip Mining Used when the terrain is flat Each new cut is parallel to the previous one. ► Contour Strip Mining Use on hilly or mountainous terrain. Overburden from each new terrace is dumped onto the one below. Mountaintop Removal ► The most drastic type of extraction method. ► Uses dynamite to break apart hard rock to expose the valuable ore beneath. ► Used primarily in the Appalachian Mountains. Mining environmental Hazards ► Scarring the Land Mining destroys land virtually permanently. ► Leaves ► Land topsoil degraded and the area wasted subsiding Usually found where subsurface mining takes place Wear the land literally caves in ► Cause Water and Air pollution Release acids into the water supply and groundwater Mining Impacts ► Metal ores are smelted or treated with (potentially toxic) chemicals to extract the desired metal. Figure 15-15 Natural Capital Degradation Extracting, Processing, and Using Nonrenewable Mineral and Energy Resources Steps Environmental effects Mining Disturbed land; mining accidents; health hazards, mine waste dumping, oil spills and blowouts; noise; ugliness; heat Exploration, extraction Processing Use Solid wastes; radioactive material; air, water, and soil pollution; noise; safety and health hazards; ugliness; heat Transportation or transmission to individual user, eventual use, and discarding Noise; ugliness; thermal water pollution; pollution of air, water, and soil; solid and radioactive wastes; safety and health hazards; heat Transportation, purification, manufacturing Fig. 15-10, p. 344 Mining Laws ► U.S. General Mining Law of 1872 Encourages mineral exploration and the mining of hard rock minerals on US public lands. ► Surface of 1977 Mining Control and Reclamation Act Required Mining Companies to reclaim lands destroyed by mining.