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 topsoil degraded and the area wasted ► Land 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

Fig , p. 344 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 Solid wastes; radioactive material; air, water, and soil pollution; noise; safety and health hazards; ugliness; heat Transportation, purification, manufacturing Use Noise; ugliness; thermal water pollution; pollution of air, water, and soil; solid and radioactive wastes; safety and health hazards; heat Transportation or transmission to individual user, eventual use, and discarding

Mining Laws ► U.S. General Mining Law of 1872  Encourages mineral exploration and the mining of hard rock minerals on US public lands. ► Surface Mining Control and Reclamation Act of 1977  Required Mining Companies to reclaim lands destroyed by mining.